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    Yersiniosis - a zoonotic foodborne disease of relevance to public health. Bancerz-Kisiel Agata,Szweda Wojciech Annals of agricultural and environmental medicine : AAEM INTRODUCTION:Y. enterocolitica is the causative agent of yersiniosis - a foodborne zoonosis with substantial importance to public health. Y. enterocolitica is widespread in the environment and animal populations, posing a potential source of infection to humans. OBJECTIVE:Presentation of yersiniosis as a zoonotic foodborne disease of relevance to public health. State of knowledge. Swine play an important role as a reservoir of Y. enterocolitica and insufficiently thermally processed pork is the main source of infection to humans. The correlation between strains isolated from pigs and from clinical cases of human yersiniosis has been sufficiently proven. Yersiniosis usually appears with gastrointestinal disturbances in children, whereas in adults it manifests in a pseudo-appendix form. The extra-enteric form of yersiniosis is rare. Classical bacteriological methods used for classifying Y. enterocolitica as pathogenic does not take into account the new aspects of the pathogenesis of yersiniosis. The examples are biotype 1A strains, commonly regarded as non-pathogenic, although they are increasingly often isolated from clinical cases of yersiniosis. Molecular methods seem much more effective and accurate in the diagnostic. New diagnostic tools such as real-time PCR, allows not only qualitative examination, but also quantitative evaluation of genes expression level, or single nucleotide polymorphism detection. CONCLUSIONS:Yersiniosis is an important food-borne zoonosis with wide range of clinical symptoms. Considering the fact that pork is the main source of infection for humans, public information campaigns seems to be an important element of the preventive measures against Y. enterocolitica infections. 10.5604/12321966.1167700
    A bacteriophage detection tool for viability assessment of Salmonella cells. Fernandes E,Martins V C,Nóbrega C,Carvalho C M,Cardoso F A,Cardoso S,Dias J,Deng D,Kluskens L D,Freitas P P,Azeredo J Biosensors & bioelectronics Salmonellosis, one of the most common food and water-borne diseases, has a major global health and economic impact. Salmonella cells present high infection rates, persistence over inauspicious conditions and the potential to preserve virulence in dormant states when cells are viable but non-culturable (VBNC). These facts are challenging for current detection methods. Culture methods lack the capacity to detect VBNC cells, while biomolecular methods (e.g. DNA- or protein-based) hardly distinguish between dead innocuous cells and their viable lethal counterparts. This work presents and validates a novel bacteriophage (phage)-based microbial detection tool to detect and assess Salmonella viability. Salmonella Enteritidis cells in a VBNC physiological state were evaluated by cell culture, flow-cytometry and epifluorescence microscopy, and further assayed with a biosensor platform. Free PVP-SE1 phages in solution showed the ability to recognize VBNC cells, with no lysis induction, in contrast to the minor recognition of heat-killed cells. This ability was confirmed for immobilized phages on gold surfaces, where the phage detection signal follows the same trend of the concentration of viable plus VBNC cells in the sample. The phage probe was then tested in a magnetoresistive biosensor platform allowing the quantitative detection and discrimination of viable and VBNC cells from dead cells, with high sensitivity. Signals arising from 3 to 4 cells per sensor were recorded. In comparison to a polyclonal antibody that does not distinguish viable from dead cells, the phage selectivity in cell recognition minimizes false-negative and false-positive results often associated with most detection methods. 10.1016/j.bios.2013.08.053
    Core-Shell Nanorod Columnar Array Combined with Gold Nanoplate-Nanosphere Assemblies Enable Powerful In Situ SERS Detection of Bacteria. Qiu Li,Wang WeiQiang,Zhang AiWen,Zhang NanNan,Lemma Tibebe,Ge HongHua,Toppari J Jussi,Hytönen Vesa P,Wang Jin ACS applied materials & interfaces Development of a label-free ultrasensitive nanosensor for detection of bacteria is presented. Sensitive assay for Gram-positive bacteria was achieved via electrostatic attraction-guided plasmonic bifacial superstructure/bacteria/columnar array assembled in one step. Dynamic optical hotspots were formed in the hybridized nanoassembly under wet-dry critical state amplifying efficiently the weak vibrational modes of three representative food-borne Gram-positive bacteria, that is, Staphylococcus xylosus, Listeria monocytogenes, and Enterococcus faecium. These three bacteria with highly analogous Raman spectra can be effectively differentiated through droplet wet-dry critical SERS approach combined with 3D PCA statistical analysis so that highly sensitive discrimination of bacterial species and samples containing mixtures of bacteria can be achieved. 10.1021/acsami.6b06674
    DNA-based hybridization chain reaction and biotin-streptavidin signal amplification for sensitive detection of Escherichia coli O157:H7 through ELISA. Guo Qi,Han Jiao-Jiao,Shan Shan,Liu Dao-Feng,Wu Song-Song,Xiong Yong-Hua,Lai Wei-Hua Biosensors & bioelectronics This study reported on a novel sandwich enzyme linked immunosorbent assay (ELISA) for the sensitive determination of Escherichia coli O157:H7 (E. coli O157:H7) by using DNA-based hybridization chain reaction (HCR) and biotin-streptavidin signal amplification. The anti-E. coli O157:H7 polyclonal antibody (pAb) was immobilized in the ELISA wells. The anti-E. coli O157:H7 monoclonal antibody (mAb) and initiator strand (DNA1) were labeled on gold nanoparticle (AuNP) to form a mAb-AuNP-DNA1 complex. In the presence of the target E. coli O157:H7, the sandwiched immunocomplex, which is pAb-E. coli O157:H7-mAb-AuNP-DNA1, could be formed. Two types of biotinylated hairpin were subsequently added in the ELISA well. A nicked double-stranded DNA (dsDNA) that contained abundant biotins was formed after HCR. Detection was performed after adding horseradish peroxidase-streptavidin and substrate/chromogen solution. Under optimal conditions, E. coli O157:H7 could be detected in the range of 5×10(2) CFU/mL to 1×10(7) CFU/mL; the limit of detection was 1.08×10(2) CFU/mL in pure culture. The LOD of the novel ELISA was 185 times lower than that of traditional ELISA. The proposed method is considerably specific and can be applied in the detection of whole milk samples inoculated with E. coli O157:H7. The coefficient of variation of in pure culture and in whole milk was 0.99-5.88% and 0.76-5.38%, respectively. This method offers a promising application in the detection of low concentrations of food-borne pathogens. 10.1016/j.bios.2016.07.049
    Single and multiple detections of foodborne pathogens by gold nanoparticle assays. Pissuwan Dakrong,Gazzana Camilla,Mongkolsuk Skorn,Cortie Michael B Wiley interdisciplinary reviews. Nanomedicine and nanobiotechnology A late detection of pathogenic microorganisms in food and drinking water has a high potential to cause adverse health impacts in those who have ingested the pathogens. For this reason there is intense interest in developing precise, rapid and sensitive assays that can detect multiple foodborne pathogens. Such assays would be valuable components in the campaign to minimize foodborne illness. Here, we discuss the emerging types of assays based on gold nanoparticles (GNPs) for rapidly diagnosing single or multiple foodborne pathogen infections. Colorimetric and lateral flow assays based on GNPs may be read by the human eye. Refractometric sensors based on a shift in the position of a plasmon resonance absorption peak can be read by the new generation of inexpensive optical spectrometers. Surface-enhanced Raman spectroscopy and the quartz microbalance require slightly more sophisticated equipment but can be very sensitive. A wide range of electrochemical techniques are also under development. Given the range of options provided by GNPs, we confidently expect that some, or all, of these technologies will eventually enter routine use for detecting pathogens in food. This article is categorized under: Diagnostic Tools > Biosensing. 10.1002/wnan.1584
    Electrochemical Biosensors for Detection of Foodborne Pathogens. Zhang Zhenguo,Zhou Jun,Du Xin Micromachines Foodborne safety has become a global public health problem in both developed and developing countries. The rapid and precise monitoring and detection of foodborne pathogens has generated a strong interest by researchers in order to control and prevent human foodborne infections. Traditional methods for the detection of foodborne pathogens are often time-consuming, laborious, expensive, and unable to satisfy the demands of rapid food testing. Owing to the advantages of simplicity, real-time analysis, high sensitivity, miniaturization, rapid detection time, and low cost, electrochemical biosensing technology is more and more widely used in determination of foodborne pathogens. Here, we summarize recent developments in electrochemical biosensing technologies used to detect common foodborne pathogens. Additionally, we discuss research challenges and future prospects for this field of study. 10.3390/mi10040222
    Development of an Electrochemical DNA Biosensor to Detect a Foodborne Pathogen. Nordin Noordiana,Yusof Nor Azah,Radu Son,Hushiarian Roozbeh Journal of visualized experiments : JoVE Vibrio parahaemolyticus (V. parahaemolyticus) is a common foodborne pathogen that contributes to a large proportion of public health problems globally, significantly affecting the rate of human mortality and morbidity. Conventional methods for the detection of V. parahaemolyticus such as culture-based methods, immunological assays, and molecular-based methods require complicated sample handling and are time-consuming, tedious, and costly. Recently, biosensors have proven to be a promising and comprehensive detection method with the advantages of fast detection, cost-effectiveness, and practicality. This research focuses on developing a rapid method of detecting V. parahaemolyticus with high selectivity and sensitivity using the principles of DNA hybridization. In the work, characterization of synthesized polylactic acid-stabilized gold nanoparticles (PLA-AuNPs) was achieved using X-ray Diffraction (XRD), Ultraviolet-visible Spectroscopy (UV-Vis), Transmission Electron Microscopy (TEM), Field-emission Scanning Electron Microscopy (FESEM), and Cyclic Voltammetry (CV). We also carried out further testing of stability, sensitivity, and reproducibility of the PLA-AuNPs. We found that the PLA-AuNPs formed a sound structure of stabilized nanoparticles in aqueous solution. We also observed that the sensitivity improved as a result of the smaller charge transfer resistance (Rct) value and an increase of active surface area (0.41 cm). The development of our DNA biosensor was based on modification of a screen-printed carbon electrode (SPCE) with PLA-AuNPs and using methylene blue (MB) as the redox indicator. We assessed the immobilization and hybridization events by differential pulse voltammetry (DPV). We found that complementary, non-complementary, and mismatched oligonucleotides were specifically distinguished by the fabricated biosensor. It also showed reliably sensitive detection in cross-reactivity studies against various food-borne pathogens and in the identification of V. parahaemolyticus in fresh cockles. 10.3791/56585
    A simple, portable, electrochemical biosensor to screen shellfish for Vibrio parahaemolyticus. Nordin Noordiana,Yusof Nor Azah,Abdullah Jaafar,Radu Son,Hushiarian Roozbeh AMB Express An earlier electrochemical mechanism of DNA detection was adapted and specified for the detection of Vibrio parahaemolyticus in real samples. The reader, based on a screen printed carbon electrode, was modified with polylactide-stabilized gold nanoparticles and methylene blue was employed as the redox indicator. Detection was assessed using a microprocessor to measure current response under controlled potential. The fabricated sensor was able to specifically distinguish complementary, non-complementary and mismatched oligonucleotides. DNA was measured in the range of 2.0 × 10-2.0 × 10 M with a detection limit of 2.16 pM. The relative standard deviation for 6 replications of differential pulse voltammetry (DPV) measurement of 0.2 µM complementary DNA was 4.33%. Additionally, cross-reactivity studies against various other food-borne pathogens showed a reliably sensitive detection of the target pathogen. Successful identification of Vibrio parahaemolyticus (spiked and unspiked) in fresh cockles, combined with its simplicity and portability demonstrate the potential of the device as a practical screening tool. 10.1186/s13568-017-0339-8
    Detection of Multiple Pathogens in Serum Using Silica-Encapsulated Nanotags in a Surface-Enhanced Raman Scattering-Based Immunoassay. Neng Jing,Li Yina,Driscoll Ashley J,Wilson William C,Johnson Patrick A Journal of agricultural and food chemistry A robust immunoassay based on surface-enhanced Raman scattering (SERS) has been developed to simultaneously detect trace quantities of multiple pathogenic antigens from West Nile virus, Rift Valley fever virus, and Yersinia pestis in fetal bovine serum. Antigens were detected by capture with silica-encapsulated nanotags and magnetic nanoparticles conjugated with polyclonal antibodies. The magnetic pull-down resulted in aggregation of the immune complexes, and the silica-encapsulated nanotags provided distinct spectra corresponding to each antigen captured. The limit of detection was ∼10 pg/mL in 20% fetal bovine serum, a significant improvement over previous studies in terms of sensitivity, level of multiplexing, and medium complexity. This highly sensitive multiplex immunoassay platform provides a promising method to detect various antigens directly in crude serum samples without the tedious process of sample preparation, which is desirable for on-site diagnostic testing and real-time disease monitoring. 10.1021/acs.jafc.8b00026
    Rapid Detection of Escherichia coli O157 and Shiga Toxins by Lateral Flow Immunoassays. Wang Jinliang,Katani Robab,Li Lingling,Hegde Narasimha,Roberts Elisabeth L,Kapur Vivek,DebRoy Chitrita Toxins Shiga toxin-producing Escherichia coli O157:H7 (STEC) cause food-borne illness that may be fatal. STEC strains enumerate two types of potent Shiga toxins (Stx1 and Stx2) that are responsible for causing diseases. It is important to detect the E. coli O157 and Shiga toxins in food to prevent outbreak of diseases. We describe the development of two multi-analyte antibody-based lateral flow immunoassays (LFIA); one for the detection of Stx1 and Stx2 and one for the detection of E. coli O157 that may be used simultaneously to detect pathogenic E. coli O157:H7. The LFIA strips were developed by conjugating nano colloidal gold particles with monoclonal antibodies against Stx1 and Stx2 and anti-lipid A antibodies to capture Shiga toxins and O157 antigen, respectively. Our results indicate that the LFIA for Stx is highly specific and detected Stx1 and Stx2 within three hours of induction of STEC with ciprofloxacin at 37 °C. The limit of detection for E. coli O157 LFIA was found to be 10⁵ CFU/mL in ground beef spiked with the pathogen. The LFIAs are rapid, accurate and easy to use and do not require sophisticated equipment or trained personnel. Following the assay, colored bands on the membrane develop for end-point detection. The LFIAs may be used for screening STEC in food and the environment. 10.3390/toxins8040092
    A novel fluorescence immunoassay for the sensitive detection of Escherichia coli O157:H7 in milk based on catalase-mediated fluorescence quenching of CdTe quantum dots. Chen Rui,Huang Xiaolin,Li Juan,Shan Shan,Lai Weihua,Xiong Yonghua Analytica chimica acta Immunoassay is a powerful tool for rapid detection of food borne pathogens in food safety monitoring. However, conventional immunoassay always suffers from low sensitivity when it employs enzyme-catalyzing chromogenic substrates to generate colored molecules as signal outputs. In the present study, we report a novel fluorescence immunoassay for the sensitive detection of E. coli O157:H7 through combination of the ultrahigh bioactivity of catalase to hydrogen peroxide (HO) and HO-sensitive mercaptopropionic acid modified CdTe QDs (MPA-QDs) as a signal transduction. Various parameters, including the concentrations of anti-E. coli O157:H7 polyclonal antibody and biotinylated monoclonal antibody, the amounts of HO and streptavidin labeled catalase (CAT), the hydrolysis temperature and time of CAT to HO, as well as the incubation time between HO and MPA-QDs, were systematically investigated and optimized. With optimal conditions, the catalase-mediated fluorescence quenching immunoassay exhibits an excellent sensitivity for E. coli O157:H7 with a detection limit of 5 × 10 CFU/mL, which was approximately 140 times lower than that of horseradish peroxidase-based colorimetric immunoassay. The reliability of the proposed method was further evaluated using E. coli O157:H7 spiked milk samples. The average recoveries of E. coli O157:H7 concentrations from 1.18 × 10 CFU/mL to 1.18 × 10 CFU/mL were in the range of 65.88%-105.6%. In brief, the proposed immunoassay offers a great potential for rapid and sensitive detection of other pathogens in food quality control. 10.1016/j.aca.2016.10.017
    A highly sensitive and flexible magnetic nanoprobe labeled immunochromatographic assay platform for pathogen Vibrio parahaemolyticus. Liu Yingying,Zhang Zhaohuan,Wang Yilong,Zhao Yong,Lu Ying,Xu Xiaowei,Yan Jun,Pan Yingjie International journal of food microbiology A magnetic nanoprobe labeled immunochromatographic test strip (MNP/ICTS) was developed to detect food-borne pathogen Vibrio parahaemolyticus. Specific antibody against V. parahaemolyticus was used as test line by coating onto the nitrocellulose membrane. Magnetic nanoprobe was prepared by immobilizing the specific antibody onto the surface of superparamagnetic nanoparticles. Specificity and sensitivity of the MNP/ICTS system were verified by artificially contaminated shrimp homogenate samples. Reliability and application feasibility of the MNP/ICTS system were demonstrated by using seafood samples (n=36). Comparing with polymerase chain reaction (PCR) and traditional culture methods, the MNP/ICTS system is found to be not only a rapid qualitative analysis (~10 min), but also an accurately quantitative detection platform. Through its rapid magnetic separation property, the MNP/ICTS system is capable to flexibly combine with a sample enrichment and pre-incubation process. This combination makes the qualitative sensitivity for the food samples surged more than 100-fold. A naked-eye observation of 1.58×10(2) CFU/g V. parahaemolyticus was realized. This sensitivity could meet the V. parahaemolyticus test threshold value in many countries. Also, the total sample pre-treatment plus MNP/ICTS assay only needs about 4.5h. Namely, we can get test results in a day. Hence, the developed MNP/ICTS assay platform is simple, rapid and highly sensitive. It is a flexible test platform for pathogen detection. The favorable comparison with PCR and culture methods further proves that the developed MNP/ICTS is applicable into food-borne pathogen or other areas where a simple, rapid, sensitive and point-of-care analysis is desirable. 10.1016/j.ijfoodmicro.2015.07.005
    Paper-Based Radial Chromatographic Immunoassay for the Detection of Pathogenic Bacteria in Milk. Luo Ke,Ryu Jian,Seol In-Hye,Jeong Ki-Baek,You Sang-Mook,Kim Young-Rok ACS applied materials & interfaces Here, a paper-based radial flow chromatographic immunoassay (RFCI) employing gold nanoparticles (AuNPs) as chromatic agents was developed for the detection of O157:H7 in whole milk. A 4-repeated gold-binding peptide-tagged (4GBP) streptococcal protein G (SPG) fusion protein was constructed as a bifunctional linker to immobilize antibodies on the surface of AuNPs with a well-oriented form based on the specific affinity of GBP and SPG to the gold and Fc portion of the antibody, respectively. 4GS@AuNPs prepared with the bifunctional linker protein exhibited excellent colloidal stability even at high salt concentrations of up to 500 mM, which is a critical requirement for its application to a broad range of biological and food samples. The enhanced colloidal stability and excellent binding capability of the immuno-4GS@AuNPs toward target bacteria lowered the detection limit of RFCI for target pathogenic bacteria in whole milk as low as 10 CFU/mL, which is by an order of magnitude lower than that of conventional immuno-AuNPs prepared with physical adsorption of antibodies. The RFCI pattern could also be converted into a grayscale value by simple image processing for quantitative determination of target pathogenic bacteria. This paper-based detection system would provide an effective means of monitoring the presence of food-borne pathogens in real food samples with naked eyes. 10.1021/acsami.9b16075
    Colorimetric Aptasensor Based on Truncated Aptamer and Trivalent DNAzyme for Vibrio parahemolyticus Determination. Sun Yuhan,Duan Nuo,Ma Pengfei,Liang Yao,Zhu Xiaoyin,Wang Zhouping Journal of agricultural and food chemistry In this work, after optimizing the original aptamer sequence by truncation and site-directed mutagenesis, a simple and sensitive colorimetric aptasensor was established for detecting the widespread food-borne pathogen Vibrio parahemolyticus ( V. parahemolyticus). The detection strategy was based on the competition for an V. parahemolyticus specific aptamer between its complementary DNA (cDNA) and V. parahemolyticus. The aptamer-conjugated magnetic nanoparticles (MNPs) were used as capture probes, and the G-quadruplex (G4) DNAzyme was employed as the signal amplifying element. Under optimal conditions, a wide linear detection range (from 10 to 10 cfu/mL) was available, and the detection limit could be as low as 10 cfu/mL. This method was also used to detect V. parahemolyticus in contaminated salmon samples, and the results showed good consistency with those obtained from standard plate counting method. Therefore, this novel aptasensor could be a good candidate for sensitive and selective detection of V. parahemolyticus without complicated operations. 10.1021/acs.jafc.8b06893
    A multicolorimetric assay for rapid detection of Listeria monocytogenes based on the etching of gold nanorods. Liu Yushen,Wang Juan,Zhao Chao,Guo Xiaoxiao,Song Xiuling,Zhao Wei,Liu Sijie,Xu Kun,Li Juan Analytica chimica acta Listeria monocytogenes (L. monocytogenes) is one of the most common food-borne pathogens. The authors describe a sensitive and reliable multicolorimetric assay for L. monocytogenes using a sensing system based on TMB etching of gold nanorods. Apt-MNP was used as the capture probe, and IgY-BSA-MnO NPs was chosen as an oxidase-like nano-artificial enzyme to oxidize TMB to generate TMB. Under the optimized conditions, the longitudinal shift of localized surface plasmon resonances had a linear correlation with the L. monocytogenes concentration in the range between 10 to 10 cfu mL. Meanwhile, the sensing system can generate vivid color responses as colorful as a rainbow, and the limit of detection is as low as 10 cfu mL at a glance. Recoveries ranging from 97.4 to 101.3% are found when analyzing spiked food samples without pre-enrichment. In our perception, it shows promise in rapid instrumental and on-site visual detection of L. monocytogenes. 10.1016/j.aca.2018.10.020
    Sensitive QD@SiO2-based immunoassay for triplex determination of cereal-borne mycotoxins. Beloglazova Natalia V,Foubert Astrid,Gordienko Anna,Tessier Mickael D,Aubert Tangi,Drijvers Emile,Goryacheva Irina,Hens Zeger,De Saeger Sarah Talanta A sensitive tool for simultaneous quantitative determination of three analytes in one single well of a microtiter plate is shown for the first time. The developed technique is based on use of colloidal quantum dot enrobed into a silica shell (QD@SiO2) derivatives as a highly responsive label. Silica-coated quantum dots were prepared and subsequently modified via the co-hydrolysis with tetraethylorthosilicate (TEOS) and various organosilane reagents. Different surface modification schemes were compared in terms of applicability of the obtained particles for the multiplex immunoassay, e.g. stability and simplicity of their conjugation with biomolecules. As model system a multiplex immunosorbent assay for screening of three mycotoxins (deoxynivalenol, zearalenone and aflatoxin B1) in cereal-based products was realized via a co-immobilization of three different specific antibodies (anti- deoxynivalenol, anti-zearalenone and anti-aflatoxin B1) in one single well of a microtiter plate. Mycotoxins were simultaneously determined by labelling their conjugates with QD@SiO2 emitting in different parts of the visible spectrum. The limits of detection for the simultaneous determination were 6.1 and 5.3, 5.4 and 4.1, and 2.6 and 1.9µgkg(-1) for deoxynivalenol, zearalenone and aflatoxin B1 in maize and wheat, respectively. As confirmatory method, liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) was used. 10.1016/j.talanta.2016.05.015
    Surface-Enhanced Raman Scattering (SERS) With Silver Nano Substrates Synthesized by Microwave for Rapid Detection of Foodborne Pathogens. Wei Caijiao,Li Mei,Zhao Xihong Frontiers in microbiology Rapid and sensitive methods have been developed to detect foodborne pathogens, a development that is important for food safety. The aim of this study is to explore Surface-enhanced Raman scattering (SERS) with silver nano substrates to detect and identify the following three foodborne pathogens: O157: H7, and . All the cells were resuspended with 10 mL silver colloidal nanoparticles, making a concentration of 10 CFU/mL, and were then exposed to 785 nm laser excitation. In this study, the results showed that all the bacteria can be sensitively and reproducibly detected directly by SERS. The distinctive differences can be observed in the SERS spectral data of the three food-borne pathogens, and the silver colloidal nanoparticles can be used as highly sensitive SERS-active substrates. In addition, the assay time required only a few minutes, which indicated that SERS coupled with the silver colloidal nanoparticles is a promising method for the detection and characterization of food-borne pathogens. At the same time, principle component analysis (PCA) and hierarchical cluster analysis (HCA) made the different bacterial strains clearly differentiated based on the barcode spectral data reduction. Therefore, the SERS methods hold great promise for the detection and identification of food-borne pathogens and even for applications in food safety. 10.3389/fmicb.2018.02857
    Visual and sensitive detection of viable pathogenic bacteria by sensing of RNA markers in gold nanoparticles based paper platform. Liu Hongxing,Zhan Fangfang,Liu Fang,Zhu Minjun,Zhou Xiaoming,Xing Da Biosensors & bioelectronics Food-borne pathogens have been recognized as a major cause of human infections worldwide. Their identification needs to be simpler, cheaper and more reliable than the traditional methods. Here, we constructed a low-cost paper platform for viable pathogenic bacteria detection with the naked eye. In this study, an effective isothermal amplification method was used to amplify the hlyA mRNA gene, a specific RNA marker in Listeria monocytogenes. The amplification products were applied to the paper-based platform to perform a visual test using sandwich hybridization assays. When the RNA products migrated along the platform by capillary action, the gold nanoparticles accumulated at the designated area. Under optimized experimental conditions, as little as 0.5 pg/μL genomic RNA from L. monocytogenes could be detected. It could also be used to specifically detect 20 CFU/mL L. monocytogenes from actual samples. The whole assay process, including RNA extraction, amplification, and visualization, can be completed within several hours. This method is suitable for point-of-care applications to detect food-borne pathogens, as it can overcome the false-positive results caused by amplifying nonviable L. monocytogenes. Furthermore, the results can be imaged and transformed into a two-dimensional bar code through an Android-based smart phone for further analysis or in-field food safety tracking. 10.1016/j.bios.2014.06.020
    Multiple Cross Displacement Amplification Combined with Gold Nanoparticle-Based Lateral Flow Biosensor for Detection of . Wang Yi,Li Hui,Li Dongxun,Li Kewei,Wang Yan,Xu Jianguo,Ye Changyun Frontiers in microbiology () is a marine seafood-borne pathogen causing severe illnesses in humans and aquatic animals. In the present study, multiple cross displacement amplification was combined with a lateral flow biosensor (MCDA-LFB) to detect the gene of in DNA extracts from pure cultures and spiked oyster homogenates. Amplification was carried out at a constant temperature (62°C) for only 30 min, and amplification products were directly applied to the biosensor. The entire process, including oyster homogenate processing (30 min), isothermal amplification (30 min) and results indicating (∼2 min), could be completed within 65 min. Amplification product was detectable from as little as 10 fg of pure DNA and from approximately 4.2 × 10 CFU in 1 mL of oyster homogenate. No cross-reaction with other species and with non- species was observed. Therefore, the MCDA-LFB method established in the current report is suitable for the rapid screening of in clinical, food, and environmental samples. 10.3389/fmicb.2016.02047
    Sensitive detection of multiple pathogens using a single DNA probe. Nordin Noordiana,Yusof Nor Azah,Abdullah Jaafar,Radu Son,Hushiarian Roozbeh Biosensors & bioelectronics A simple but promising electrochemical DNA nanosensor was designed, constructed and applied to differentiate a few food-borne pathogens. The DNA probe was initially designed to have a complementary region in Vibrio parahaemolyticus (VP) genome and to make different hybridization patterns with other selected pathogens. The sensor was based on a screen printed carbon electrode (SPCE) modified with polylactide-stabilized gold nanoparticles (PLA-AuNPs) and methylene blue (MB) was employed as the redox indicator binding better to single-stranded DNA. The immobilization and hybridization events were assessed using differential pulse voltammetry (DPV). The fabricated biosensor was able to specifically distinguish complementary, non-complementary and mismatched oligonucleotides. DNA was measured in the range of 2.0×10(-9)-2.0×10(-13)M with a detection limit of 5.3×10(-12)M. The relative standard deviation for 6 replications of DPV measurement of 0.2µM complementary DNA was 4.88%. The fabricated DNA biosensor was considered stable and portable as indicated by a recovery of more than 80% after a storage period of 6 months at 4-45°C. Cross-reactivity studies against various food-borne pathogens showed a reliably sensitive detection of VP. 10.1016/j.bios.2016.06.077
    Biofunctionalized gold nanoparticles for colorimetric sensing of botulinum neurotoxin A light chain. Liu Xiaohu,Wang Yi,Chen Peng,Wang Yusong,Zhang Jinling,Aili Daniel,Liedberg Bo Analytical chemistry Botulinum neurotoxin is considered as one of the most toxic food-borne substances and is a potential bioweapon accessible to terrorists. The development of an accurate, convenient, and rapid assay for botulinum neurotoxins is therefore highly desirable for addressing biosafety concerns. Herein, novel biotinylated peptide substrates designed to mimic synaptosomal-associated protein 25 (SNAP-25) are utilized in gold nanoparticle-based assays for colorimetric detection of botulinum neurotoxin serotype A light chain (BoLcA). In these proteolytic assays, biotinylated peptides serve as triggers for the aggregation of gold nanoparticles, while the cleavage of these peptides by BoLcA prevents nanoparticle aggregation. Two different assay strategies are described, demonstrating limits of detection ranging from 5 to 0.1 nM of BoLcA with an overall assay time of 4 h. These hybrid enzyme-responsive nanomaterials provide rapid and sensitive detection for one of the most toxic substances known to man. 10.1021/ac402626g
    Bio-distribution and interaction with dopamine of fluorescent nanodots from roasted chicken. Song Xunyu,Wang Haitao,Zhang Run,Yu Chenxu,Tan Mingqian Food & function The potential health risks of food-borne nanoparticles are of great concern to public health. In this work, the formation and physicochemical properties of a class of fluorescent nanodots (FNDs) in roasted chicken were investigated. It was found that as the roasting temperature increased from 200 to 300 °C the size of the FNDs decreased significantly, from 17.1 to 2.1 nm. The FNDs, which mainly contain carbon (65%), are strongly fluorescent under ultraviolet light, exhibiting an excitation-dependent emission behavior. The fluorescence quantum yields of the FNDs were determined at 200, 250, and 300 °C, and were found to be 6.71 ± 0.21, 12.85 ± 0.34 and 17.46 ± 0.42%, respectively. These FNDs not only could be taken up by live cells and dispersed within the cytoplasm, but also could pass the blood-brain barrier (BBB) and accumulated in the brains of mice after oral feeding. The results of the fluorescence and Fourier transform infrared (FTIR) spectroscopy analysis clearly indicated that the FNDs can interact with the neurotransmitter dopamine in vitro through the formation of fluorescent conjugates. The relative cell viability decreased by 33% corresponding to FND-300 at a concentration of 4 mg mL-1. These results confirmed the presence of the FNDs in roasted chicken and revealed their potential bioeffects on human health, which calls for more research and evaluation. 10.1039/c8fo01159a
    Fabrication of an electrochemical DNA-based biosensor for Bacillus cereus detection in milk and infant formula. Izadi Zahra,Sheikh-Zeinoddin Mahmoud,Ensafi Ali A,Soleimanian-Zad Sabihe Biosensors & bioelectronics This paper describes fabrication of a DNA-based Au-nanoparticle modified pencil graphite electrode (PGE) biosensor for detection of Bacillus cereus, causative agent of two types of food-borne disease, i.e., emetic and diarrheal syndrome. The sensing element of the biosensor was comprised of gold nanoparticles (GNPs) self-assembled with single-stranded DNA (ssDNA) of nheA gene immobilized with thiol linker on the GNPs modified PGE. The size, shape and dispersion of the GNPs were characterized by field emission scanning electron microscope (FESEM). Detection of B. cereus was carried out based on an increase in the charge transfer resistance (Rct) of the biosensor due to hybridization of the ss-DNA with target DNA. An Atomic force microscope (AFM) was used to confirm the hybridization. The biosensor sensitivity in pure cultures of B. cereus was found to be 10(0) colony forming units per milliliter (CFU/mL) with a detection limit of 9.4 × 10(-12) mol L(-1). The biosensor could distinguish complementary from mismatch DNA sequence. The proposed biosensor exhibited a rapid detection, low cost, high sensitivity to bacterial contamination and could exclusively and specifically detect the target DNA sequence of B. cereus from other bacteria that can be found in dairy products. Moreover, the DNA biosensor exhibited high reproducibility and stability, thus it may be used as a suitable biosensor to detect B. cereus and to become a portable system for food quality control. 10.1016/j.bios.2016.02.032
    Surface-enhanced Raman spectroscopic single step detection of Vibrio parahaemolyticus using gold coated polydimethylsiloxane as the active substrate and aptamer modified gold nanoparticles. Wu Shijia,Duan Nuo,Shen Mofei,Wang Jing,Wang Zhouping Mikrochimica acta A method is described for single-step detection of V. parahaemolyticus in seafood via aptamer-based SERS. A gold-coated polydimethylsiloxane (PDMS) film was used for the enhancement of Raman scattering. The Raman reporter 4-mercaptobenzoic acid was linked to aptamer modified gold nanoparticles (AuNPs) served as a signalling probe. The negatively charged signalling probe was assembled onto the cysteamine-modified Au-PDMS film through electrostatic adsorption. On addition of V. parahaemolyticus, it will be bound by the aptamer as a biorecognition element, and this leads to the dissociation of the signalling probe from the Au-PDMS film. Hence, the Raman signal (at 1592 cm) decreases. The assay has a wide linear response that covers the 1.2 × 10 to 1.2 × 10 cfu·mL V. parahaemolyticus concentration range. The detection limit is 12 cfu·mL. The method was successfully applied to the determination of V. parahaemolyticus in oyster and salmon samples. Graphical abstract Schematic presentation of a surface-enhanced Raman spectroscopic method for single step detection of Vibrio parahaemolyticus using gold coated polydimethylsiloxane as the active substrate and aptamer modified gold nanoparticles. This solid substrate simplified the analysis procedures and enhanced the sensitivity. 10.1007/s00604-019-3499-1
    High-throughput detection of food-borne pathogenic bacteria using oligonucleotide microarray with quantum dots as fluorescent labels. Huang Aihua,Qiu Zhigang,Jin Min,Shen Zhiqiang,Chen Zhaoli,Wang Xinwei,Li Jun-Wen International journal of food microbiology Bacterial pathogens are mostly responsible for food-borne diseases, and there is still substantial room for improvement in the effective detection of these organisms. In the present study, we explored a new method to detect target pathogens easily and rapidly with high sensitivity and specificity. This method uses an oligonucleotide microarray combined with quantum dots as fluorescent labels. Oligonucleotide probes targeting the 16SrRNA gene were synthesized to create an oligonucleotide microarray. The PCR products labeled with biotin were subsequently hybridized using an oligonucleotide microarray. Following incubation with CdSe/ZnS quantum dots coated with streptavidin, fluorescent signals were detected with a PerkinElmer Gx Microarray Scanner. The results clearly showed specific hybridization profiles corresponding to the bacterial species assessed. Two hundred and sixteen strains of food-borne bacterial pathogens, including standard strains and isolated strains from food samples, were used to test the specificity, stability, and sensitivity of the microarray system. We found that the oligonucleotide microarray combined with quantum dots used as fluorescent labels can successfully discriminate the bacterial organisms at the genera or species level, with high specificity and stability as well as a sensitivity of 10 colony forming units (CFU)/mL of pure culture. We further tested 105 mock-contaminated food samples and achieved consistent results as those obtained from traditional biochemical methods. Together, these results indicate that the quantum dot-based oligonucleotide microarray has the potential to be a powerful tool in the detection and identification of pathogenic bacteria in foods. 10.1016/j.ijfoodmicro.2014.05.012
    Rapid Identification of Mixed Enteropathogenic Bacteria by Means of Au Nanoparticles@Bacteria Using Portable Raman Spectrometer. Zheng Da-Wei,Liu Xiao-Ying,Zhang Ping,Su Lan,Wang Li-Min,Wei Xiao-Dan,Wang Hui-Qin,Lin Tai-Feng Journal of nanoscience and nanotechnology Rapid detection of food-borne pathogens is the most critical and urgent issue among all the current food safety problems. As enhanced substrate, nanoparticles are widely used in surface enhanced Raman scattering (SERS) because of unique optical and physicochemical properties. In this study, Au nanoparticles with monodisperse and good reproducibility were synthesized by using sodium citrate reduction method. Applying Au nanoparticles sol as enhanced substrate, a portable Raman spectrometer had been applied for rapid detection of single and mixture pathogenic bacterial contamination by SERS. The results indicated that Escherichia coli, Salmonella typhimirium, Shigella flexner and Staphylococcus aureus showed specific Raman phenotypes at 600∼1700 cm-1. Generally, different bacteria could be easily and instantly recognized by its Raman phenotypes. The PC-LDA classification model was set up by combined bacterial Raman phenotypes with the multivariate statistical analysis. With the short-time inoculation, four enteropathogenic bacteria could be rapidly, precisely, sensitively and specifically identified. Furthermore, the model also had a good ability to predict the mixed contamination. This research provides the possibility of rapid detection in the food and biomedical fields. 10.1166/jnn.2018.15510
    A composite prepared from carboxymethyl chitosan and aptamer-modified gold nanoparticles for the colorimetric determination of Salmonella typhimurium. Yi Jiecan,Wu Pian,Li Guiyin,Xiao Wen,Li Lei,He Yayuan,He Yafei,Ding Ping,Chen Cuimei Mikrochimica acta An aptamer-based assay is described for the determination of Salmonella typhimurium (S. typh). Carboxymethyl chitosan was loaded with amino-modified aptamer against S. typh, and then adsorbed on gold nanoparticles by electrostatic interaction to form a composite that acts as the molecular recognition element. In the presence of S. typh, it will be bound by the aptamer, and this changes the structure of the recognition element. On addition of salt solution, the gold nanoparticles agglomerate so that the color of the solution changes from red to blue. S. typh can be detected via measurement of the absorbance at 550 nm. Absorbance increases linearly with the logarithm of the S. typh concentration in the range from 100 to 10 cfu·mL. The limit of detection is 16 cfu·mL. The specificity and practicability of the assay were evaluated. The recoveries of S. typh from spiked milk samples are between 92.4 and 97.2%. The analytical results are basically consistent with those of a plate counting method. Graphical abstract Schematic representation of the colorimetric assay for Salmonella typhimuium (S. typh) using carboxymethyl chitosan (CMCS)-aptamer (Apt)-gold nanoparticles (AuNPs) composites. 10.1007/s00604-019-3827-5
    Copolymer Brush-Based Ultralow-Fouling Biorecognition Surface Platform for Food Safety. Vaisocherová-Lísalová Hana,Surman František,Víšová Ivana,Vala Milan,Špringer Tomáš,Ermini Maria Laura,Šípová Hana,Šedivák Petr,Houska Milan,Riedel Tomáš,Pop-Georgievski Ognen,Brynda Eduard,Homola Jiří Analytical chemistry Functional polymer coatings that combine the ability to resist nonspecific fouling from complex media with high biorecognition element (BRE) immobilization capacity represent an emerging class of new functional materials for a number of bioanalytical and biosensor technologies for medical diagnostics, security, and food safety. Here, we report on a random copolymer brush surface - poly(CBMAA-ran-HPMAA) - providing high BRE immobilization capacity while simultaneously exhibiting ultralow-fouling behavior in complex food media. We demonstrate that both the functionalization and fouling resistance capabilities of such copolymer brushes can be tuned by changing the surface contents of the two monomer units: nonionic N-(2-hydroxypropyl) methacrylamide (HPMAA) and carboxy-functional zwitterionic carboxybetaine methacrylamide (CBMAA). It is demonstrated that the resistance to fouling decreases with the surface content of CBMAA; poly(CBMAA-ran-HPMAA) brushes with CBMAA molar content up to 15 mol % maintain excellent resistance to fouling from a variety of homogenized foods (hamburger, cucumber, milk, and lettuce) even after covalent attachment of BREs to carboxy groups of CBMAA. The poly(CBMAA 15 mol %-ran-HPMAA) brushes functionalized with antibodies are demonstrated to exhibit fouling resistance from food samples by up to 3 orders of magnitude better when compared with the widely used low-fouling carboxy-functional oligo(ethylene glycol) (OEG)-based alkanethiolate self-assembled monolayers (AT SAMs) and, furthermore, by up to 2 orders of magnitude better when compared with the most successful ultralow-fouling biorecognition coatings - poly(carboxybetaine acrylamide), poly(CBAA). When model SPR detections of food-borne bacterial pathogens in homogenized foods are used, it is also demonstrated that the antibody-functionalized poly(CBMAA 15 mol %-ran-HPMAA) brush exhibits superior biorecognition properties over the poly(CBAA). 10.1021/acs.analchem.6b02617
    Electrochemical Biosensors: A Solution to Pollution Detection with Reference to Environmental Contaminants. Hernandez-Vargas Gustavo,Sosa-Hernández Juan Eduardo,Saldarriaga-Hernandez Sara,Villalba-Rodríguez Angel M,Parra-Saldivar Roberto,Iqbal Hafiz M N Biosensors The increasing environmental pollution with particular reference to emerging contaminants, toxic heavy elements, and other hazardous agents is a serious concern worldwide. Considering this global issue, there is an urgent need to design and develop strategic measuring techniques with higher efficacy and precision to detect a broader spectrum of numerous contaminants. The development of precise instruments can further help in real-time and in-process monitoring of the generation and release of environmental pollutants from different industrial sectors. Moreover, real-time monitoring can also reduce the excessive consumption of several harsh chemicals and reagents with an added advantage of on-site determination of contaminant composition prior to discharge into the environment. With key scientific advances, electrochemical biosensors have gained considerable attention to solve this problem. Electrochemical biosensors can be an excellent fit as an analytical tool for monitoring programs to implement legislation. Herein, we reviewed the current trends in the use of electrochemical biosensors as novel tools to detect various contaminant types including toxic heavy elements. A particular emphasis was given to screen-printed electrodes, nanowire sensors, and paper-based biosensors and their role in the pollution detection processes. Towards the end, the work is wrapped up with concluding remarks and future perspectives. In summary, electrochemical biosensors and related areas such as bioelectronics, and (bio)-nanotechnology seem to be growing areas that will have a marked influence on the development of new bio-sensing strategies in future studies. 10.3390/bios8020029
    Yeast Biosensors for Detection of Environmental Pollutants: Current State and Limitations. Jarque Sergio,Bittner Michal,Blaha Ludek,Hilscherova Klara Trends in biotechnology Yeast biosensors have become suitable tools for the screening and detection of environmental pollutants because of their various advantages compared to other sensing technologies. On the other hand, many limitations remain with regard to their optimal performance and applicability in several contexts, such as low-concentration samples and on-site testing. This review summarizes the current state of yeast biosensors, with special focus on screening and assessment of environmental contaminants, discusses both pros and cons, and suggests steps towards their further development and effective use in the environmental assessment. 10.1016/j.tibtech.2016.01.007
    Recent biosensing developments in environmental security. Wanekaya Adam K,Chen Wilfred,Mulchandani Ashok Journal of environmental monitoring : JEM Environmental security is one of the fundamental requirements of our well being. However, it still remains a major global challenge. Therefore, in addition to reducing and/or eliminating the amounts of toxic discharges into the environment, there is need to develop techniques that can detect and monitor these environmental pollutants in a sensitive and selective manner to enable effective remediation. Because of their integrated nature, biosensors are ideal for environmental monitoring and detection as they can be portable and provide selective and sensitive rapid responses in real time. In this review we discuss the main concepts behind the development of biosensors that have most relevant applications in the field of environmental monitoring and detection. We also review and document recent trends and challenges in biosensor research and development particularly in the detection of species of environmental significance such as organophosphate nerve agents, heavy metals, organic contaminants, pathogenic microorganisms and their toxins. Special focus will be given to the trends that have the most promising applications in environmental security. We conclude by highlighting the directions towards which future biosensors research in environmental security sector might proceed. 10.1039/b806830p
    Recent trends in rapid environmental monitoring of pathogens and toxicants: potential of nanoparticle-based biosensor and applications. Koedrith Preeyaporn,Thasiphu Thalisa,Weon Jong-Il,Boonprasert Rattana,Tuitemwong Kooranee,Tuitemwong Pravate TheScientificWorldJournal Of global concern, environmental pollution adversely affects human health and socioeconomic development. The presence of environmental contaminants, especially bacterial, viral, and parasitic pathogens and their toxins as well as chemical substances, poses serious public health concerns. Nanoparticle-based biosensors are considered as potential tools for rapid, specific, and highly sensitive detection of the analyte of interest (both biotic and abiotic contaminants). In particular, there are several limitations of conventional detection methods for water-borne pathogens due to low concentrations and interference with various enzymatic inhibitors in the environmental samples. The increase of cells to detection levels requires long incubation time. This review describes current state of biosensor nanotechnology, the advantage over conventional detection methods, and the challenges due to testing of environmental samples. The major approach is to use nanoparticles as signal reporter to increase output rather than spending time to increase cell concentrations. Trends in future development of novel detection devices and their advantages over other environmental monitoring methodologies are also discussed. 10.1155/2015/510982
    Green synthesized nickel nanoparticles for targeted detection and killing of S. typhimurium. Jeyaraj Pandian Chitra,Palanivel Rameshthangam,Balasundaram Usha Journal of photochemistry and photobiology. B, Biology Simple and sensitive colorimetric immunosensor based on peroxidase mimetic activity and photothermal effect of nickel oxide nanoparticle (NiOGs) has been developed to detect and kill food borne pathogen Salmonella typhimurium. NiOGs showed superior peroxidase mimetic activity for oxidation of peroxidase substrate 3, 3', 5, 5'-tetramethylbenzidine (TMB). Oxidation of TMB by NiOGs followed Michaelis-Menten kinetics with K and V values of 0.25mM and 2.64×10M/s respectively. NiOGs was coated with citric acid (CA-NiOGs) followed by conjugation with antibody (anti-S. typhimurium) (Ab-CA-NiOGs) that effectively captured S. typhimurium. Colorimetric detection of S. typhimurium by Ab-CA-NiOGs showed a linear relationship between pathogen concentration (1×10 to 1×10cfu/mL) and color signal (652nm) with limit of detection (LOD) of 10cfu/mL. The proposed method showed no cross reactivity against other pathogens. Recovery of S. typhimurium in milk and juice samples was found to be 95 to 100% and 92 to 99% respectively. NiOGs exposed to laser irradiation showed dose dependent increase in temperature and singlet oxygen within 5min. Bacteria bound to Ab-CA-NiOGs after laser irradiation, induced membrane damage and reduced bacterial viability to 6%. The bifunctional peroxidase-mimetic activity and photothermal effect of NiOGs can be exploited in selective sensing and killing of target pathogens respectively in food products. 10.1016/j.jphotobiol.2017.07.014
    Biosynthesis of silver nanoparticles and polyhydroxybutyrate nanocomposites of interest in antimicrobial applications. Castro-Mayorga J L,Freitas F,Reis M A M,Prieto M A,Lagaron J M International journal of biological macromolecules This study deals with the optimization and scaling up of the production of poly(3-hydroxybutyrate), PHB, nanocomposites containing biosynthesized silver nanoparticles (AgNPs) to generate materials with antimicrobial performance. First, a comparative study of the chemical and biological synthesis of AgNPs during the fermentation process of Cupriavidus necator at shake flask-scale was carried out. These experiments demonstrated the inherent capacity of C. necator to reduce the silver salt and produce AgNPs without the need for adding a reducing agent and, that the method of synthesis (with or without reducing agent) affects the dispersion of the AgNPs and their antimicrobial performance. Finally, the process was scaled-up to a 10Liters bioreactor and the relevant physical properties of the PHB-AgNPs nanocomposites pressed into films were determined. From the characterization work, the AgNPs were found to be well dispersed and distributed into the polymer matrix, having a maximum frequency of particles with average diameter of 76-95nm. Moreover, the presence of AgNPs did not cause any effect on the thermal properties of the biopolymer, although a slight reduction in crystallinity was seen. The developed materials presented a strong antimicrobial activity against the food-borne pathogens Salmonella enterica and Listeria monocytogenes, which makes them potentially suitable for active coatings and packaging applications. Complete biodisintegration of the samples occurred during composting conditions within the first 40days. Interestingly, the presence of the AgNPs did not impair the profile of biodegradation of the microbial polymer. 10.1016/j.ijbiomac.2017.12.007
    Mechanistic Investigation of the Biological Effects of SiO₂, TiO₂, and ZnO Nanoparticles on Intestinal Cells. Setyawati Magdiel I,Tay Chor Yong,Leong David T Small (Weinheim an der Bergstrasse, Germany) Silicon dioxide (SiO2), titanium dioxide (TiO2), and zinc oxide (ZnO) are currently among the most widely used nanoparticles (NPs) in the food industry. This could potentially lead to unintended exposure of the gastrointestinal tract to these NPs. This study aims to investigate the potential side-effects of these food-borne NPs on intestinal cells and to mechanistically understand the observed biological responses. Among the panel of tested NPs, ZnO NPs are the most toxic. Consistently in all three tested intestinal cell models, ZnO NPs invoke the most inflammatory responses from the cells and induce the highest intracellular production of reactive oxygen species (ROS). The elevated ROS levels induce significant damage to the DNA of the cells, resulting in cell-cycle arrest and subsequently cell death. In contrast, both SiO2 and TiO2 NPs elicit minimum biological responses from the intestinal cells. Overall, the study showcases the varying capability of the food-borne NPs to induce a cellular response in the intestinal cells. In addition to physicochemical differences in the NPs, the genetic landscape of the intestinal cell models governs the toxicology profile of these food-borne NPs. 10.1002/smll.201403232
    Colorimetric Immunoassay for Rapid Detection of Vibrio parahemolyticus Based on Mn Mediates the Assembly of Gold Nanoparticles. Fu Kaiyue,Zheng Yan,Li Juan,Liu Yushen,Pang Bo,Song Xiuling,Xu Kun,Wang Juan,Zhao Chao Journal of agricultural and food chemistry Vibrio parahemolyticus ( V. parahemolyticus) is an important food-borne pathogen that causes food poisoning and acute gastroenteritis in humans. Herein, a novel colorimetric immunoassay was presented for rapid detection of V. parahemolyticus using gold nanoparticles (18.1 nm diameter) as chromogenic substrate, whose combination of a magnetic bead-based sandwich immunoassay and an optical sensing system via Mn ions mediated aggregation of gold nanoparticles. MnO nanoparticles coated with polyclonal IgG antibodies (7.8 nm diameter) are used to recognize the target and can be etched to generate manganese ions by ascorbic acid. A color change ranging from red to purple to blue can be easily discerned by bare eye, corresponding to V. parahemolyticus concentration in the range between 10 and 10 cfu·mL. The proposed method possesses high specificity with a limit of detection of 10 cfu·mL and was successfully applied to determination of V. parahemolyticus in oyster samples without pre-enrichment. In our perception, it shows promise in rapid instrumental and on-site visual detection of V. parahemolyticus. 10.1021/acs.jafc.8b02494
    Status of biomolecular recognition using electrochemical techniques. Sadik Omowunmi A,Aluoch Austin O,Zhou Ailing Biosensors & bioelectronics The use of nanoscale materials (e.g., nanoparticles, nanowires, and nanorods) for electrochemical biosensing has seen explosive growth in recent years following the discovery of carbon nanotubes by Sumio Ijima in 1991. Although the resulting label-free sensors could potentially simplify the molecular recognition process, there are several important hurdles to be overcome. These include issues of validating the biosensor on statistically large population of real samples rather than the commonly reported relatively short synthetic oligonucleotides, pristine laboratory standards or bioreagents; multiplexing the sensors to accommodate high-throughput, multianalyte detection as well as application in complex clinical and environmental samples. This article reviews the status of biomolecular recognition using electrochemical detection by analyzing the trends, limitations, challenges and commercial devices in the field of electrochemical biosensors. It provides a survey of recent advances in electrochemical biosensors including integrated microelectrode arrays with microfluidic technologies, commercial multiplex electrochemical biosensors, aptamer-based sensors, and metal-enhanced electrochemical detection (MED), with limits of detection in the attomole range. Novel applications are also reviewed for cancer monitoring, detection of food pathogens, as well as recent advances in electrochemical glucose biosensors. 10.1016/j.bios.2008.10.003
    Emerging Trends in Advanced Nanomaterials Based Electrochemical Genosensors. Kaushik Mahima,Khurana Sonia,Mehra Komal,Yadav Neelam,Mishra Sujeet,Kukreti Shrikant Current pharmaceutical design Advanced nanomaterials indubitably represent one of the most propitious class of new materials due to their intriguing optical, electronic and redox properties. The incredible progress achieved in this research area has been propelled by the development of novel synthetic procedures owing to the emergence of nanotechnology and by the wide range of applications. These nanostructured materials possess high surface area, biocompatibility, nontoxicity and charge-sensitive conductance which have led to the development of simple, rapid, highly sensitive, inexpensive and portable electrochemical genosensors. This review accentuates on the development and validation of various advanced nanomaterials based electrochemical genosensors that utilize unique properties of nanomaterials for signal transduction purpose or as an electroactive species for direct detection of analyte. The intent is to highlight the recent progress on highly sensitive and flexible nanostructured material based electrochemical genosensors that have the potential to be developed as the next generation field-deployable analytical tools. 10.2174/1381612824666181109154919
    Review of Electrochemical DNA Biosensors for Detecting Food Borne Pathogens. Wu Qiaoyun,Zhang Yunzhe,Yang Qian,Yuan Ning,Zhang Wei Sensors (Basel, Switzerland) The vital importance of rapid and accurate detection of food borne pathogens has driven the development of biosensor to prevent food borne illness outbreaks. Electrochemical DNA biosensors offer such merits as rapid response, high sensitivity, low cost, and ease of use. This review covers the following three aspects: food borne pathogens and conventional detection methods, the design and fabrication of electrochemical DNA biosensors and several techniques for improving sensitivity of biosensors. We highlight the main bioreceptors and immobilizing methods on sensing interface, electrochemical techniques, electrochemical indicators, nanotechnology, and nucleic acid-based amplification. Finally, in view of the existing shortcomings of electrochemical DNA biosensors in the field of food borne pathogen detection, we also predict and prospect future research focuses from the following five aspects: specific bioreceptors (improving specificity), nanomaterials (enhancing sensitivity), microfluidic chip technology (realizing automate operation), paper-based biosensors (reducing detection cost), and smartphones or other mobile devices (simplifying signal reading devices). 10.3390/s19224916
    Advances in Nanoporous Anodic Alumina-Based Biosensors to Detect Biomarkers of Clinical Significance: A Review. Rajeev Gayathri,Prieto Simon Beatriz,Marsal Lluis F,Voelcker Nicolas H Advanced healthcare materials There is a strong and growing demand for compact, portable, rapid, and low-cost devices to detect biomarkers of interest in clinical and point-of-care diagnostics. Such devices aid in early diagnosis of diseases without the need to rely on expensive and time-consuming large instruments in dedicated laboratories. Over the last decade, numerous biosensors have been developed for detection of a wide range of clinical biomarkers including proteins, nucleic acids, growth factors, and bacterial enzymes. Various transduction techniques have been reported based on biosensor technology that deliver substantial advances in analytical performance, including sensitivity, reproducibility, selectivity, and speed for monitoring a wide range of human health conditions. Nanoporous anodic alumina (NAA) has been used extensively for biosensing applications due to its inherent optical and electrochemical properties, ease of fabrication, large surface area, tunable properties, and high stability in aqueous environment. This review focuses on NAA-based biosensing systems for detection of clinically significant biomarkers using various detection techniques with the main focus being on electrochemical and optical transduction methods. The review covers an overview of the importance of biosensors for biomarkers detection, general (surface and structural) properties and fabrication of NAA, and NAA-based biomarker sensing systems. 10.1002/adhm.201700904
    Nanostructured Electrochemical Biosensors for Label-Free Detection of Water- and Food-Borne Pathogens. Reta Nekane,Saint Christopher P,Michelmore Andrew,Prieto-Simon Beatriz,Voelcker Nicolas H ACS applied materials & interfaces The emergence of nanostructured materials has opened new horizons in the development of next generation biosensors. Being able to control the design of the electrode interface at the nanoscale combined with the intrinsic characteristics of the nanomaterials engenders novel biosensing platforms with improved capabilities. The purpose of this review is to provide a comprehensive and critical overview of the latest trends in emerging nanostructured electrochemical biosensors. A detailed description and discussion of recent approaches to construct label-free electrochemical nanostructured electrodes is given with special focus on pathogen detection for environmental monitoring and food safety. This includes the use of nanoscale materials such as nanotubes, nanowires, nanoparticles, and nanosheets as well as porous nanostructured materials including nanoporous anodic alumina, mesoporous silica, porous silicon, and polystyrene nanochannels. These platforms may pave the way toward the development of point-of-care portable electronic devices for applications ranging from environmental analysis to biomedical diagnostics. 10.1021/acsami.7b13943
    Design and Elementary Evaluation of a Highly-Automated Fluorescence-Based Instrument System for On-Site Detection of Food-Borne Pathogens. Lu Zhan,Zhang Jianyi,Xu Lizhou,Li Yanbin,Chen Siyu,Ye Zunzhong,Wang Jianping Sensors (Basel, Switzerland) A simple, highly-automated instrument system used for on-site detection of foodborne pathogens based on fluorescence was designed, fabricated, and preliminarily tested in this paper. A corresponding method has been proved effective in our previous studies. This system utilizes a light-emitting diode (LED) to excite fluorescent labels and a spectrometer to record the fluorescence signal from samples. A rotation stage for positioning and switching samples was innovatively designed for high-throughput detection, ten at most in one single run. We also developed software based on LabVIEW for data receiving, processing, and the control of the whole system. In the test of using a pure quantum dot (QD) solution as a standard sample, detection results from this home-made system were highly-relevant with that from a well-commercialized product and even slightly better reproducibility was found. And in the test of three typical kinds of food-borne pathogens, fluorescence signals recorded by this system are highly proportional to the variation of the sample concentration, with a satisfied limit of detection (LOD) (nearly 10²-10³ CFU·mL in food samples). Additionally, this instrument system is low-cost and easy-to-use, showing a promising potential for on-site rapid detection of food-borne pathogens. 10.3390/s17030442
    A quantum-dot-based fluoroassay for detection of food-borne pathogens. Mohamadi Elaheh,Moghaddasi Mohammadali,Farahbakhsh Afshin,Kazemi Abbass Journal of photochemistry and photobiology. B, Biology Evaluation of the distribution capability of food-borne pathogens existing in food products by taking the advantage of quantum dots (QDs) for their photoluminescence properties was carried out. Bacteria namely Escherichia coli (E. coli) labelled with CdSe-QDs were examined both on an Agar nutrient and ground fish substrates in order to observe their growth rate in different environments in the Lab. A sample with an appropriate concentration ratio 10CFU/mL of bacteria/CdSe-QDs was empirically selected from the samples which were grown on the Agar containing plates. The selected sample was also tested on a ground fish substrate as a real food sample. The bacterial growth was observed under the irradiation of UV light and the growth patterns were investigated for 3 successive days. The growth patterns indicated that E. coli can stay alive and can be distributed on food products so that the growth can be easily monitored. This approach makes bacterial growth on food products detectable so that it can be used as a bacteria-QD assay for an easy detection of food borne pathogens grown on a food sample. 10.1016/j.jphotobiol.2017.08.005
    Evaluation of gold nanoparticle based lateral flow assays for diagnosis of enterobacteriaceae members in food and water. Singh Jyoti,Sharma Shivesh,Nara Seema Food chemistry Lateral flow immunoassays (LFIAs) are advantageous over conventional detection methods in terms of their simplicity and rapidity. These assays have been reported using various types of labels but colloidal gold nanoparticles are still the preferred choice as a label because of their easy synthesis, visual detection and stability. Bacterial contamination of food and drinking water is a major threat and hindrance towards ensuring food and water safety. Enterobacteriaceae family members are mainly transmitted by the consumption of contaminated water and food and implicated in various food or water borne infections. The LFIAs have been popularly used for detection of bacterial cells in different matrices. Therefore, this review intends to provide an analysis of the gold nanoparticle based lateral flow assays developed for detecting enterobacteriaceae family members in food and water samples. The review includes detailed data and discusses the factors that influence the performance of LFIAs and their shortcomings. 10.1016/j.foodchem.2014.08.092
    Biosynthesis of Silver Nanoparticles from and Investigation of their Potential Impacts on Food Safety and Control. Mohanta Yugal K,Panda Sujogya K,Bastia Akshaya K,Mohanta Tapan K Frontiers in microbiology Silver nanoparticles play an integral part in the evolution of new antimicrobials against the broad ranges of pathogenic microorganisms. Recently, biological synthesis of metal nanoparticles using plant extracts has been successfully consummated. In the present study, the biosynthesis of silver nanoparticles (AgNPs) was conducted using the leaf extract of plant , having novel ethnomedicinal. The synthesized AgNPs were characterized using UV-Visible spectroscopy, dynamic light scattering spectroscopy (DLS), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy. The DLS study revealed the surface charge of the resulted nanoparticles that was highly negative, i.e., -25.0 ± 7.84 mV and the size was 74.56 ± 0.46 nm. The phytochemical and FTIR analysis confirmed the role of water-soluble phyto-compounds for the reduction of silver ions to silver nanoparticles. The potential antibacterial activity of AgNPs was studied against the food borne pathogens viz. (IC = 74.26 ± 0.14 μg/ml), (IC = 84.28 ± 0.36 μg/ml), (IC = 94.43 ± 0.4236 μg/ml). The antioxidant potential of AgNPs was evaluated using 1, 1-diphenyl-2-picryl-hydrazil (IC = 6.78 ± 0.15 μg/ml) and hydroxyl radical assay (IC = 89.58 ± 1.15 μg/ml). In addition, the cytotoxicity of AgNPs was performed against fibroblast cell line L-929 to evaluate their biocompatibility. The overall results of the present investigation displayed the potential use of leaf extract as a good bio-resource for the biosynthesis of AgNPs and their implementation in diverse applications, specifically as antibacterial agent in food packaging and preservation to combat against various food borne pathogenic bacteria along with its pharmaceutical and biomedical applications. 10.3389/fmicb.2017.00626
    Novel immunochromatographic assay based on Eu (III)-doped polystyrene nanoparticle-linker-monoclonal antibody for sensitive detection of Escherichia coli O157:H7. Xing Ke-Yu,Peng Juan,Liu Dao-Feng,Hu Li-Ming,Wang Chun,Li Guo-Qiang,Zhang Gang-Gang,Huang Zhen,Cheng Song,Zhu Fang-Fei,Liu Na-Mei,Lai Wei-Hua Analytica chimica acta Colloidal gold immunochromatographic assay (ICA) has poor sensitivity when used for Escherichia coli O157:H7 (E. coli O157:H7) detection. Eu (III)-doped polystyrene nanoparticle (EuNP) has a large range of stokes shift, long decay time, and wide excitation spectrum and narrow emission spectra. EuNP has been used as novel probe in ICA to improve sensitivity. In this study, carboxyl-modified EuNPs were prepared with different linkers. ICA based on EuNP, EuNP-6 carbon chain (CC) complex, EuNP-200CC complex, EuNP-1000CC complex, and EuNP-streptavidin (EuNP-SA) complex were systematically compared for the detection of E. coli O157:H7. Under optimized working conditions, the limits of detection (LOD) of EuNP-ICA, EuNP-6CC-ICA, EuNP-200CC-ICA, EuNP-1000CC-ICA, and EuNP-SA-ICA were 9.54 × 10, 1.59 × 10, 3.18 × 10, 2.98 × 10, and 1.08 × 10 colony-forming units (CFU) mL, respectively. The linear ranges of EuNP-ICA, EuNP-6CC-ICA, EuNP-200CC-ICA, EuNP-1000CC-ICA, and EuNP-SA-ICA were 6.36 × 10-1.59 × 10, 3.18 × 10-1.59 × 10, 6.36 × 10-1.59 × 10, 6.36 × 10-1.59 × 10, and 8.0 × 10-1.59 × 10 CFU mL, respectively. EuNP-SA-ICA exhibited the highest sensitivity and the widest linear range with good specificity, accuracy, and precision. It could be a promising analytical method for detecting E. coli O157:H7 in food samples. EuNP-SA-ICA may be a good model for detecting low concentrations of other food-borne pathogens. 10.1016/j.aca.2017.10.027
    Advanced molecular diagnostic techniques for detection of food-borne pathogens: Current applications and future challenges. Umesha S,Manukumar H M Critical reviews in food science and nutrition The elimination of disease-causing microbes from the food supply is a primary goal and this review deals with the overall techniques available for detection of food-borne pathogens. Now-a-days conventional methods are replaced by advanced methods like Biosensors, Nucleic Acid-based Tests (NAT), and different PCR-based techniques used in molecular biology to identify specific pathogens. Bacillus cereus, Staphylococcus aureus, Proteus vulgaris, Escherichia coli, Campylobacter, Listeria monocytogenes, Salmonella spp., Aspergillus spp., Fusarium spp., Penicillium spp., and pathogens are detected in contaminated food items that cause always diseases in human in any one or the other way. Identification of food-borne pathogens in a short period of time is still a challenge to the scientific field in general and food technology in particular. The low level of food contamination by major pathogens requires specific sensitive detection platforms and the present area of hot research looking forward to new nanomolecular techniques for nanomaterials, make them suitable for the development of assays with high sensitivity, response time, and portability. With the sound of these, we attempt to highlight a comprehensive overview about food-borne pathogen detection by rapid, sensitive, accurate, and cost affordable in situ analytical methods from conventional methods to recent molecular approaches for advanced food and microbiology research. 10.1080/10408398.2015.1126701
    Antibacterial Activity of Fructus forsythia Essential Oil and the Application of EO-Loaded Nanoparticles to Food-Borne Pathogens. Guo Na,Gai Qing-Yan,Jiao Jiao,Wang Wei,Zu Yuan-Gang,Fu Yu-Jie Foods (Basel, Switzerland) essential oil (FEO) with excellent antibacterial activity was rarely reported. The objective of the present study was to investigate the antibacterial activity and the antibacterial mechanism of FEO against two food-borne pathogenic bacteria, () and () in vitro. When treated FEO, the zones of inhibition (ZOI) of (20.5 ± 0.25 mm) and (24.3 ± 0.21 mm) were much larger than control ( < 0.05). The minimum inhibitory concentrations (MICs) of FEO were 3.13 mg/mL and 1.56 mg/mL for and , respectively. The antibacterial mechanism of FEO against was due to the changes in permeability and integrity of cell membrane leading to the leakage of nucleic acids and proteins. With the superior antibacterial activity of FEO, the nano-encapsulation method has been applied in FEO. When compared to FEO and blank chitosan nanoparticles, FEO-loaded nanoparticles (chitosan to FEO of 1:1) can effectively inhibit the growth of above 90% at room temperature. It is necessary to consider that FEO and FEO-loaded nanoparticles will become promising antibacterial additives for food preservative, cosmetic, and pharmaceutical applications. 10.3390/foods5040073
    Paper-based magnetic nanoparticle-peptide probe for rapid and quantitative colorimetric detection of Escherichia coli O157:H7. Suaifan Ghadeer A R Y,Alhogail Sahar,Zourob Mohammed Biosensors & bioelectronics There is a critical and urgent demand for a simple, rapid and specific qualitative and quantitative colorimetric biosensor for the detection of the food contaminant Escherichia coli O157:H7 (E. coli O157:H7) in complex food products due to the recent outbreaks of food-borne diseases. Traditional detection techniques are time-consuming, require expensive instrumentation and are labour-intensive. To overcome these limitations, a novel, ultra-rapid visual biosensor was developed based on the ability of E. coli O157:H7 proteases to change the optical response of a surface-modified, magnetic nanoparticle-specific (MNP-specific) peptide probe. Upon proteolysis, a gradual increase in the golden color of the sensor surface was visually observed. The intensification of color was correlated with the E. coli O157:H7 concentration. The color change resulting from the dissociation of the self-assembled monolayer (SAM) was detected by the naked eye and analysed using an image analysis software (ImageJ) for the purpose of quantitative detection. This biosensor demonstrated high sensitivity and applicability, with lower limits of detection of 12CFUmL in broth samples and 30-300CFUmL in spiked complex food matrices. In conclusion, this approach permits the use of a disposable biosensor chip that can be mass-produced at low cost and can be used not only by food manufacturers but also by regulatory agencies for better control of potential health risks associated with the consumption of contaminated foods. 10.1016/j.bios.2016.10.023
    Zero valent silver nanoparticles capped with capsaicinoids containing Capsicum annuum extract, exert potent anti-biofilm effect on food borne pathogen Staphylococcus aureus and curtail planktonic growth on a zebrafish infection model. Lotha Robert,Shamprasad Bhanuvalli R,Sundaramoorthy Niranjana Sri,Ganapathy Ragavi,Nagarajan Saisubramanian,Sivasubramanian Aravind Microbial pathogenesis Food plants Hungarian wax pepper (HWP) and Green Bell pepper (GBP), belonging to Capsicum annuum were utilized for biogenic fabrication of zero valent, nano-silver (AgNPs) through a photo-mediation procedure. In the bacterial strains evaluated, HWP/GBP AgNPs demonstrated effective bacteriostatic and bactericidal effect against Staphylococcus aureus. Time kill results portrayed that HWP/GBP nano-silver exhibited comparable bactericidal potency on S. aureus. Anti-biofilm potential of HWP/GBP AgNPs displayed significant effects at sub MIC levels, by triggering 50% biofilm reduction of the food spoilage microbe S. aureus, inferring that the anti-biofilm outcome is not dependent on antibacterial result, and this was confirmed by SEM and fluorescence studies. Histopathological analyses of S. aureus infected zebrafish liver did not display any abnormality changes such as extensive cell death and degeneration, upon treatment with HWP/GBP AgNPs and the zero-valent silver nanoparticles were comparatively less toxic and more operative in restraining the bioburden in S. aureus infected zebrafish model by a >1.7 log fold. Ability of light reduced HWP/GBP AgNPs to alleviate the in vitro and in vivo planktonic mode of growth and curb the biofilm formation of S. aureus is also demonstrated. 10.1016/j.micpath.2018.08.053
    Mechanistic aspects of biologically synthesized silver nanoparticles against food- and water-borne microbes. Krishnaraj Chandran,Harper Stacey L,Choe Ho Sung,Kim Kwang-Pyo,Yun Soon-Il Bioprocess and biosystems engineering In the present study, silver nanoparticles (AgNPs) synthesized from aqueous leaves extract of Malva crispa and their mode of interaction with food- and water-borne microbes were investigated. Formation of AgNPs was conformed through UV-Vis, FE-SEM, EDS, AFM, and HR-TEM analyses. Further the concentration of silver (Ag) in the reaction mixture was conformed through ICP-MS analysis. Different concentration of nanoparticles (1-3 mM) tested to know the inhibitory effect of bacterial pathogens such as Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, Salmonella typhi, Salmonella enterica and the fungal pathogens of Penicillium expansum, Penicillium citrinum, Aspergillus oryzae, Aspergillus sojae and Aspergillus niger. Interestingly, nanoparticles synthesized from 2 to 3 mM concentration of AgNO3 showed excellent inhibitory activities against both bacterial and fungal pathogens which are well demonstrated through well diffusion, poison food technique, minimum inhibitory concentration (MIC), and minimum fungicidal concentration (MFC). In addition, mode of interaction of nanoparticles into both bacterial and fungal pathogens was documented through Bio-TEM analysis. Further the genomic DNA isolated from test bacterial strains and their interaction with nanoparticles was carried out to elucidate the possible mode of action of nanoparticles against bacteria. Interestingly, AgNPs did not show any genotoxic effect against all the tested bacterial strains which are pronounced well in agarose gel electrophoresis and for supporting this study, UV-Vis and Bio-TEM analyses were carried out in which no significant changes observed compared with control. Hence, the overall results concluded that the antimicrobial activity of biogenic AgNPs occurred without any DNA damage. 10.1007/s00449-015-1436-1
    Plant extract-mediated biogenic synthesis of silver, manganese dioxide, silver-doped manganese dioxide nanoparticles and their antibacterial activity against food- and water-borne pathogens. Krishnaraj Chandran,Ji Byoung-Jun,Harper Stacey L,Yun Soon-Il Bioprocess and biosystems engineering Silver nanoparticles (AgNPs), manganese dioxide nanoparticles (MnO₂NPs) and silver-doped manganese dioxide nanoparticles (Ag-doped MnO₂NPs) were synthesized by simultaneous green chemistry reduction approach. Aqueous extract from the leaves of medicinally important plant Cucurbita pepo was used as reducing and capping agents. Various characterization techniques were carried out to affirm the formation of nanoparticles. HR-TEM analysis confirmed the size of nanoparticles in the range of 15-70 nm and also metal doping was confirmed through XRD and EDS analyses. FT-IR analysis confirmed that the presence of biomolecules in the aqueous leaves extract was responsible for nanoparticles synthesis. Further, the concentration of metals and their doping in the reaction mixture was achieved by ICP-MS. The growth curve and well diffusion study of synthesized nanoparticles were performed against food- and water-borne Gram-positive and Gram-negative bacterial pathogens. The mode of interaction of nanoparticles on bacterial cells was demonstrated through Bio-TEM analysis. Interestingly, AgNPs and Ag-doped MnO₂NPs showed better antibacterial activity against all the tested bacterial pathogens; however, MnO₂NPs alone did not show any antibacterial properties. Hence, AgNPs and Ag-doped MnO₂NPs synthesized from aqueous plant leaves extract may have important role in controlling various food spoilage caused by bacteria. 10.1007/s00449-016-1556-2
    Plant nutraceuticals (Quercetrin and Afzelin) capped silver nanoparticles exert potent antibiofilm effect against food borne pathogen Salmonella enterica serovar Typhi and curtail planktonic growth in zebrafish infection model. Lotha Robert,Sundaramoorthy Niranjana Sri,Shamprasad Bhanuvalli R,Nagarajan Saisubramanian,Sivasubramanian Aravind Microbial pathogenesis Purified plant nutraceuticals afzelin and quercetrin from an edible plant- Crotolaria tetragona was employed for the fabrication of silver nanoparticles (AgNPs) by a sunlight mediated process. From among a panel of strains tested, AgNPs displayed potent bacteriostatic and bactericidal effect against P. aeruginosa and S. Typhi. Time kill studies revealed green synthesized AgNPs displayed comparable bactericidal effect with chemically synthesized AgNPs against S. Typhi. Antibiofilm potential of AgNPs showed that they were highly effective at sub MIC concentrations in causing 50% biofilm inhibition against food borne pathogen S. Typhi implying that antibiofilm effect is independent of antibacterial effect, which was evidenced by fluorescent imaging and SEM imaging. Mechanistic studies revealed that reduced cell surface hydrophobicity, decreased surface adherence, loss of membrane potential contributed to antibiofilm potential of afzelin/quercetrin AgNPs. Green synthesized afzelin/quercetrin AgNPs were also relatively less toxic and more effective in curtailing bioburden of S. Typhi in infected zebrafish by > 3 log fold. Ability of sunlight reduced afzelin/quercetrin NPs to mitigate planktonic mode of growth in vitro and in vivo and curtail biofilm formation of S. Typhi in vitro demonstrates its potential to curtail food borne pathogen in planktonic and biofilm mode of growth. 10.1016/j.micpath.2018.04.044
    Effects of food-borne ZnO nanoparticles on intestinal microbiota of common carp (Cyprinus carpio L.). Chupani Latifeh,Barta Jiri,Zuskova Eliska Environmental science and pollution research international Ingestion of nanoparticles (NPs) with antimicrobial properties may disrupt the balance of intestinal microbiota. To investigate the effects of zinc oxide (ZnO) NPs on intestinal flora, common carp Cyprinus carpio were fed a commercial feed containing 500 mg kg ZnO NPs for 6 weeks and compared to a control group receiving a similar feed-only regime. Sequencing data were analyzed both in individual fish and in pooled samples. Sequencing of 16S rRNA encoding gene of individual specimens revealed high variation in intestinal microbial composition. Assessment of pooled results can obscure high individual variation in data. ZnO NPs consumption was not associated with a significant difference in the intestinal microbial community compared to untreated controls. Our results indicated a high individual variation in the intestinal microbiome, which may further point out the importance of functional study over microbial composition to address nanomaterials-microbiome relationship. 10.1007/s11356-019-05616-x
    Antibacterial activity of a novel Forsythia suspensa fruit mediated green silver nanoparticles against food-borne pathogens and mechanisms investigation. Du Juan,Hu Zheyuan,Yu Ziyue,Li Hailong,Pan Jie,Zhao Dianbo,Bai Yanhong Materials science & engineering. C, Materials for biological applications In the present study, novel silver nanoparticles (AgNPs) were synthesized via a green method by using Forsythia suspensa fruit water extract. The synthesized AgNPs showed antibacterial activities against all the tested food-borne pathogens, including Listeria monocytogenes, Vibrio parahaemolyticus, Escherichia coli O157:H7, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhimurium. Furthermore, the S. aureus and V. parahaemolyticus were introduced as Gram-positive and Gram-negative model strains to explore the antibacterial mechanism of AgNPs. Minimal inhibitory concentrations (MICs) of V. parahaemolyticus and S. aureus were 6.25 μg/mL and 50 μg/mL, respectively, and the minimum bactericidal concentrations (MBCs) of V. parahaemolyticus and S. aureus were 12.5 μg/mL and 100 μg/mL, respectively. Results indicated that the AgNPs caused morphological alterations and damaged the membrane integrity of strains S. aureus and V. parahaemolyticus. In addition, the AgNPs induced the release of nucleic acids of V. parahaemolyticus cells, resulting in disrupting of cells reproduction. 10.1016/j.msec.2019.04.031
    Effects of food-borne nanomaterials on gastrointestinal tissues and microbiota. Bouwmeester Hans,van der Zande Meike,Jepson Mark A Wiley interdisciplinary reviews. Nanomedicine and nanobiotechnology Ingestion of engineered nanomaterials is inevitable due to their addition to food and prevalence in food packaging and domestic products such as toothpaste and sun cream. In the absence of robust dosimetry and particokinetic data, it is currently challenging to accurately assess the potential toxicity of food-borne nanomaterials. Herein, we review current understanding of gastrointestinal uptake mechanisms, consider some data on the potential for toxicity of the most commonly encountered classes of food-borne nanomaterials (including TiO , SiO ZnO, and Ag nanoparticles), and discuss the potential impact of the luminal environment on nanoparticle properties and toxicity. Much of our current understanding of gastrointestinal nanotoxicology is derived from increasingly sophisticated epithelial models that augment in vivo studies. In addition to considering the direct effects of food-borne nanomaterials on gastrointestinal tissues, including the potential role of chronic nanoparticle exposure in development of inflammatory diseases, we also discuss the potential for food-borne nanomaterials to disturb the normal balance of microbiota within the gastrointestinal tract. The latter possibility warrants close attention given the increasing awareness of the critical role of microbiota in human health and the known impact of some food-borne nanomaterials on bacterial viability. WIREs Nanomed Nanobiotechnol 2018, 10:e1481. doi: 10.1002/wnan.1481 This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials. 10.1002/wnan.1481
    Silver Nanoparticles Synthesized Using Wild Mushroom Show Potential Antimicrobial Activities against Food Borne Pathogens. Mohanta Yugal Kishore,Nayak Debasis,Biswas Kunal,Singdevsachan Sameer Kumar,Abd Allah Elsayed Fathi,Hashem Abeer,Alqarawi Abdulaziz A,Yadav Dhananjay,Mohanta Tapan Kumar Molecules (Basel, Switzerland) The present study demonstrates an economical and eco-friendly method for the synthesis of silver nanoparticles (AgNPs) using the wild mushroom . The synthesis of AgNPs was confirmed and the products characterized by UV-visible spectroscopy, dynamic light scattering spectroscopy and X-ray diffraction analysis. Furthermore, Fourier transform infrared spectroscopy (ATR-FTIR) analysis was performed to identify the viable biomolecules involved in the capping and active stabilization of AgNPs. Moreover, the average sizes and morphologies of AgNPs were analyzed by field emission scanning electron microscopy (FE-SEM). The potential impacts of AgNPs on food safety and control were evaluated by the antimicrobial activity of the synthesized AgNPs against common food-borne bacteria, namely, , , , and . The results of this study revealed that the synthesized AgNPs can be used to control the growth of food-borne pathogens and have potential application in the food packaging industry. Moreover, the AgNPs were evaluated for antioxidant activity (aDPPH), for biocompatibility (L-929, normal fibroblast cells), and for cytotoxic effects on human breast adenosarcoma cells (MCF-7 & MDA-MB231) to highlight their potential for use in a variety of bio-applications. 10.3390/molecules23030655
    Hydrophilic Food-Borne Nanoparticles from Beef Broth as Novel Nanocarriers for Zinc. Geng Jiaxin,Song Xunyu,Zhang Xuedi,Tie Shanshan,Cao Lin,Tan Mingqian Journal of agricultural and food chemistry Food-borne nanoparticles (FNs) may be used as nanocarriers for metal ion chelation in micronutrient supplements. In this paper, the preparation and characterization of hydrophilic FNs were reported from beef broth cooked with a pressure cooker at 117 °C for different periods (30, 50, and 70 min) and their potential application as nanocarriers for zinc was investigated. The broth FNs are quasi-spherical with good water solubility and ultrasmall size, which can emit a strong sapphire color under 365 nm ultraviolet irradiation. X-ray photoelectron spectroscopy (XPS) analysis showed that there are carboxyl, amino, and hydroxyl groups on the FNs, which are useful for Zn(II) chelation. The vibration band of C═O at 1688 cm in the infrared spectrum of FNs shifted to 1718 cm after binding with Zn(II) ions, suggesting the participation of the carbonyl group in Zn(II) ion chelation. The appearance of Zn XPS peaks, at 1021.6 and 1045 eV for Zn(II)-FNs, clearly demonstrated the formation of Zn-O between the FNs and zinc ions. Biodistribution of FNs and the Zn(II)-FN complex in normal rat kidney cells demonstrated that they could easily enter normal rat kidney cells. A downfield was found for the signals of Zn(II)-FNs in H nuclear magnetic resonance spectroscopy and strongly suggested the binding of Zn(II) ions to FNs through carboxylic acid, hydroxyl, and amine groups. In addition, no obvious cytotoxicity was found for Zn(II)-FNs compared to zinc (ZnSO) and commercial zinc gluconate. The results revealed that the FNs from beef broth may have a potential as nanocarriers for zinc chelation. 10.1021/acs.jafc.9b01372
    Graphene-interfaced electrical biosensor for label-free and sensitive detection of foodborne pathogenic E. coli O157:H7. Pandey Ashish,Gurbuz Yasar,Ozguz Volkan,Niazi Javed H,Qureshi Anjum Biosensors & bioelectronics E. coli O157:H7 is an enterohemorrhagic bacteria responsible for serious foodborne outbreaks that causes diarrhoea, fever and vomiting in humans. Recent foodborne E. coli outbreaks has left a serious concern to public health. Therefore, there is an increasing demand for a simple, rapid and sensitive method for pathogen detection in contaminated foods. In this study, we developed a label-free electrical biosensor interfaced with graphene for sensitive detection of pathogenic bacteria. This biosensor was fabricated by interfacing graphene with interdigitated microelectrodes of capacitors that were biofunctionalized with E. coli O157:H7 specific antibodies for sensitive pathogenic bacteria detection. Here, graphene nanostructures on the sensor surface provided superior chemical properties such as high carrier mobility and biocompatibility with antibodies and bacteria. The sensors transduced the signal based on changes in dielectric properties (capacitance) through (i) polarization of captured cell-surface charges, (ii) cells' internal bioactivity, (iii) cell-wall's electronegativity or dipole moment and their relaxation and (iv) charge carrier mobility of graphene that modulated the electrical properties once the pathogenic E. coli O157:H7 captured on the sensor surface. Sensitive capacitance changes thus observed with graphene based capacitors were specific to E. coli O157:H7 strain with a sensitivity as low as 10-100 cells/ml. The proposed graphene based electrical biosensor provided advantages of speed, sensitivity, specificity and in-situ bacterial detection with no chemical mediators, represents a versatile approach for detection of a wide variety of other pathogens. 10.1016/j.bios.2016.12.041
    Centrifugal loop-mediated isothermal amplification microdevice for rapid, multiplex and colorimetric foodborne pathogen detection. Oh Seung Jun,Park Byung Hyun,Jung Jae Hwan,Choi Goro,Lee Doh C,Kim Do Hyun,Seo Tae Seok Biosensors & bioelectronics We present a centrifugal microfluidic device which enables multiplex foodborne pathogen identification by loop-mediated isothermal amplification (LAMP) and colorimetric detection using Eriochrome Black T (EBT). Five identical structures were designed in the centrifugal microfluidic system to perform the genetic analysis of 25 pathogen samples in a high-throughput manner. The sequential loading and aliquoting of the LAMP cocktail, the primer mixtures, and the DNA sample solutions were accomplished by the optimized zigzag-shaped microchannels and RPM control. We targeted three kinds of pathogenic bacteria (Escherichia coli O157:H7, Salmonella typhimurium and Vibrio parahaemolyticus) and detected the amplicons of the LAMP reaction by the EBT-mediated colorimetric method. For the limit-of-detection (LOD) test, we carried out the LAMP reaction on a chip with serially diluted DNA templates of E. coli O157:H7, and could observe the color change with 380 copies. The used primer sets in the LAMP reaction were specific only to the genomic DNA of E. coli O157:H7, enabling the on-chip selective, sensitive, and high-throughput pathogen identification with the naked eyes. The entire process was completed in 60min. Since the proposed microsystem does not require any bulky and expensive instrumentation for end-point detection, our microdevice would be adequate for point-of-care (POC) testing with high simplicity and high speed, providing an advanced genetic analysis microsystem for foodborne pathogen detection. 10.1016/j.bios.2015.08.052
    Microfluidic devices for sample preparation and rapid detection of foodborne pathogens. Kant Krishna,Shahbazi Mohammad-Ali,Dave Vivek Priy,Ngo Tien Anh,Chidambara Vinayaka Aaydha,Than Linh Quyen,Bang Dang Duong,Wolff Anders Biotechnology advances Rapid detection of foodborne pathogens at an early stage is imperative for preventing the outbreak of foodborne diseases, known as serious threats to human health. Conventional bacterial culturing methods for foodborne pathogen detection are time consuming, laborious, and with poor pathogen diagnosis competences. This has prompted researchers to call the current status of detection approaches into question and leverage new technologies for superior pathogen sensing outcomes. Novel strategies mainly rely on incorporating all the steps from sample preparation to detection in miniaturized devices for online monitoring of pathogens with high accuracy and sensitivity in a time-saving and cost effective manner. Lab on chip is a blooming area in diagnosis, which exploits different mechanical and biological techniques to detect very low concentrations of pathogens in food samples. This is achieved through streamlining the sample handling and concentrating procedures, which will subsequently reduce human errors and enhance the accuracy of the sensing methods. Integration of sample preparation techniques into these devices can effectively minimize the impact of complex food matrix on pathogen diagnosis and improve the limit of detections. Integration of pathogen capturing bio-receptors on microfluidic devices is a crucial step, which can facilitate recognition abilities in harsh chemical and physical conditions, offering a great commercial benefit to the food-manufacturing sector. This article reviews recent advances in current state-of-the-art of sample preparation and concentration from food matrices with focus on bacterial capturing methods and sensing technologies, along with their advantages and limitations when integrated into microfluidic devices for online rapid detection of pathogens in foods and food production line. 10.1016/j.biotechadv.2018.03.002
    Application of Hyperspectral Imaging as a Nondestructive Technique for Foodborne Pathogen Detection and Characterization. Bonah Ernest,Huang Xingyi,Aheto Joshua Harrington,Osae Richard Foodborne pathogens and disease Microbial food safety is a persistent and exacting global issue due to the multiplicity and complexity of foods and food production systems. Foodborne illnesses caused by foodborne bacterial pathogens frequently occur, thus endangering the safety and health of human beings. Factors such as pretreatments, that is, culturing, enrichment, amplification make the traditional routine identification and enumeration of large numbers of bacteria in a complex microbial consortium complex, expensive, and time-consuming. Therefore, the need for rapid point-of-use detection systems for foodborne bacterial pathogens with high sensitivity and specificity is crucial in food safety control. Hyperspectral imaging (HSI) as a powerful testing technology provides a rapid, nondestructive approach for pathogen detection. This article reviews some fundamental information about HSI, including instrumentation, data acquisition, image processing, and data analysis-the current application of HSI for the detection, classification, and discrimination of various foodborne pathogens. The merits and demerits of HSI for pathogen detection as well as current and future trends are discussed. Therefore, the purpose of this review is to provide a brief overview of HSI, and further lay emphasis on the emerging trend and importance of this technique for foodborne pathogen detection. 10.1089/fpd.2018.2617
    Developments in Micro- and Nanotechnology for Foodborne Pathogen Detection. Carlson Krista,Misra Manoranjan,Mohanty Swomitra Foodborne pathogens and disease In response to the potential hazards associated with the globalization of the food industry, research has been focused on the development of new sensing techniques to provide the means of contamination detection at any stage in the food supply chain. The demand for on-site detection is growing as pre-emptive sensing of pathogens could eliminate foodborne-related outbreaks and associated healthcare costs. Reduction in food waste is also a driver for point-of-use (POU) sensing, from both an economic and environmental standpoint. The following review discusses the latest advancements in platforms that have the greatest potential for inexpensive, real-time detection, and identification of foodborne pathogens. Specific focus has been placed on the development techniques, which utilize micro- and nanoscale technology. Sample preparation-free techniques are also discussed, as the growing demand to enable POU sensing at any stage in the food supply chain will be a major driver toward the advancements of these nondestructive methods. 10.1089/fpd.2017.2309
    Emerging needs and opportunities in foodborne disease detection and prevention: From tools to people. Hoelzer Karin,Moreno Switt Andrea I,Wiedmann Martin,Boor Kathryn J Food microbiology A variety of technological advances have tremendously improved the ability of surveillance systems to detect and prevent foodborne disease cases and outbreaks. Molecular subtyping methods and surveillance systems, including PFGE and, more recently, whole genome sequencing (WGS) have been particularly important advances, but the responsible food vehicle and causative agent are still only conclusively determined in a small fraction of outbreaks. Microbial foodborne disease cases continue to take a considerable public health toll, primarily in developing countries. According to recent WHO estimates, at least 600 million cases of foodborne illness and 420,000 associated deaths occur each year; the true numbers are likely significantly higher. This review summarizes the current and anticipated global impact of improved technologies for foodborne disease surveillance and proposes key areas that will require particular attention, including the need for training activities, public-private partnerships supporting food safety, and appropriate food safety policy frameworks. The manuscript places particular focus on the development of WGS tools for surveillance of Listeria monocytogenes because this technology represents one of the most disruptive food safety technologies introduced over the last 10 years, which has revolutionized routine surveillance of L. monocytogenes in several countries. As such, it provides valuable insights into how technological advances can improve foodborne illness surveillance and illustrates the training, policy and infrastructure needs created by introduction of disruptive novel technologies. Moreover, WGS can help identify new sources of foodborne outbreaks and inform risk assessments, thereby providing valuable insights for risk-based policies aimed at preventing future foodborne illness. 10.1016/j.fm.2017.07.006