•Current advances and perspectives of smartphone-assisted biosensors towards foodborne pathogens are proposed.•Role of nanotechnology in smartphone-assisted biosensors is elucidated.•The recognition ...modes for targeting foodborne pathogens are described.•The smartphone POC platforms in foodborne pathogens detection are discussed.
Pathogens are one of the supreme threats for the public health around the world in food supply chain. The on-site monitoring is an emerging trend for screening pathogens during the food processing and preserving. Traditional analytical tools have been unable to satisfy the current demands. Smartphones have enormous potentials for achieving on-site detection of foodborne pathogens, with intrinsic advantages such as small size, high accessibility, fast processing speed, and powerful imaging capacity. This review aims to synthesize the current advances in smartphone-assisted biosensors (SABs) for sensing foodborne pathogens, and briefly put forward the problem that consist in the research. We present the role of nanotechnology and recognition modes targeting foodborne pathogens in SABs, and discuss the signal conversion platforms coupling with smartphone. The challenges and perspectives in SABs are also proposed. The smartphone analytics area is moving forward, and it much be subject to careful quality standards and validation.
This study aimed to assess the effect of coating based on nanochitosan-whey protein isolate (NCH-WPI) containing summer savory essential oil (SEO) combined with oxygen absorber (OA) packaging on ...Pseudomonas aeruginosa, Listeria monocytogenes, and Escherichia coli O157H7, inoculated to rainbow trout fillets stored under refrigeration. Except control and OA groups, L. monocytogenes decreased (0.49–1.82 log CFU/g) in all treatment groups until the eighth day, and then increased (0.39–0.68 log CFU/g). This indicates that the treatments were ineffective to inhibit the proliferation of this bacterium. Considering the forced aerobic nature of inoculated P. aeruginosa, the counts of these bacteria become undetectable in groups packed with OA after the fourth day of storage, while the other groups showed an increase (0.99–2.23 log CFU/g) in this bacteria population during entire storage period. This growth rate was slower in the NCH-WPI + 1%SEO and NCH-WPI + 2%SEO groups. Regarding the inoculated E. coli, its count was decreased (1.48–2.41 log CFU/g) during storage, and this reduction (2.24–2.41 log CFU/g) was the highest in NCH-WPI + 1%SEO + OA and NCH-WPI + 2%SEO + OA groups. In conclusion, NCH-WPI treatments delayed the growth of all pathogenic bacteria, but the ternary treatment (NCH-WPI + SEO + OA) was the most effective treatment in this regard.
Many consumers are demanding foods without what they perceive as artificial and harmful chemicals, including many used as antimicrobials and preservatives in food. Consequently, interest in more ...natural, non-synthesized, antimicrobials as potential alternatives to conventional antimicrobials to extend shelf life and combat foodborne pathogens has heightened. Aromatic plants and their components have been examined as potential inhibitors of bacterial growth and most of their properties have been linked to essential oils and other secondary plant metabolites. Historically, essential oils from different sources have been widely promoted for their potential antimicrobial capabilities. In this review, mechanisms of antimicrobial action, and the antimicrobial properties of plant essential oils are discussed, including their mode of action, effectiveness, synergistic effects, major components and use in foods.
The viable but non-culturable (VBNC) state, a unique state in which a number of bacteria respond to adverse circumstances, was first discovered in 1982. Unfortunately, it has been reported that many ...foodborne pathogens can be induced to enter the VBNC state by the limiting environmental conditions during food processing and preservation, such as extreme temperatures, drying, irradiation, pulsed electric field, and high pressure stress, as well as the addition of preservatives and disinfectants. After entering the VBNC state, foodborne pathogens will introduce a serious crisis to food safety and public health because they cannot be detected using conventional plate counting techniques. This review provides an overview of the various features of the VBNC state, including the biological characteristics, induction and resuscitation factors, formation and resuscitation mechanisms, detection methods, and relationship to food safety.
Antimicrobial resistance (AMR) is a major public health problem that requires publicly available tools for rapid analysis. To identify AMR genes in whole-genome sequences, the National Center for ...Biotechnology Information (NCBI) has produced AMRFinder, a tool that identifies AMR genes using a high-quality curated AMR gene reference database. The Bacterial Antimicrobial Resistance Reference Gene Database consists of up-to-date gene nomenclature, a set of hidden Markov models (HMMs), and a curated protein family hierarchy. Currently, it contains 4,579 antimicrobial resistance proteins and more than 560 HMMs. Here, we describe AMRFinder and its associated database. To assess the predictive ability of AMRFinder, we measured the consistency between predicted AMR genotypes from AMRFinder and resistance phenotypes of 6,242 isolates from the National Antimicrobial Resistance Monitoring System (NARMS). This included 5,425
, 770
spp., and 47
isolates phenotypically tested against various antimicrobial agents. Of 87,679 susceptibility tests performed, 98.4% were consistent with predictions. To assess the accuracy of AMRFinder, we compared its gene symbol output with that of a 2017 version of ResFinder, another publicly available resistance gene detection system. Most gene calls were identical, but there were 1,229 gene symbol differences (8.8%) between them, with differences due to both algorithmic differences and database composition. AMRFinder missed 16 loci that ResFinder found, while ResFinder missed 216 loci that AMRFinder identified. Based on these results, AMRFinder appears to be a highly accurate AMR gene detection system.
Efficient identification of pathogenic bacteria is greatly concerned with microbial food safety and foodborne diseases diagnosis. Surface-enhanced Raman scattering (SERS) tags are among the ...cutting-edge tools for bioanalysis, but facing troubles in either SERS sensitivity, durability, interfering signals, or universal recognition agents for target bacteria. This work proposed a multivariate scheme enabled by polyphenolic chemistry for the green synthesis, facile stabilization (functionalization), protective encapsulation, and bio-affinitive design of metal-phenolic networks (MPNs)-encapsulated silver SERS nanotags (AgNPs@4-mercaptobenzonitrile@MPNs). With remarkable SERS properties, shelf stability, and bacterial affinity, AgNPs@4-mercaptobenzonitrile@MPNs tags enabled rapid, reproducible, and interference-free SERS detection of two representative foodborne pathogens (i.e., E. coli O157: H7 and S. aureus) in the assistance of an aptamer-labelled magnetic probe, reaching good sensitivity and selectivity. Moreover, this SERS biosensor worked well in real food samples, manifesting the potential of polyphenolic chemistry in the customization of bio-affinitive SERS nanotags for food safety detection.
Display omitted
•Polyphenolic chemistry enabled from-synthesis-to-bioaffinity scheme of SERS tags.•Metal-phenolic networks acted as bioaffinity elements for bacterial recognition.•Polyphenolic SERS tags could be reliable detection probe for bacteria quantitation.•Polyphenolic SERS biosensor could detect foodborne bacteria down to 102 CFU/mL.•The SERS biosensor could work in milk and beef samples.
Foodborne pathogens are a grave concern for the for food, medical, environmental, and economic sectors. Their ease of transmission and resistance to treatments, such as antimicrobial agents, make ...them an important challenge. Food tainted with these pathogens is swiftly rejected, and if ingested, can result in severe illnesses and even fatalities. This review provides and overview of the current status of various pathogens and their metabolites transmitted through food. Despite a plethora of studies on treatments to eradicate and inhibit these pathogens, their indiscriminate use can compromise the sensory properties of food and lead to contamination. Therefore, the study of detection methods such as electrochemical biosensors has been proposed, which are devices with advantages such as simplicity, fast response, and sensitivity. However, these biosensors may also present some limitations. In this regard, it has been reported that nanomaterials with high conductivity, surface-to-volume ratio, and robustness have been observed to improve the detection of foodborne pathogens or their metabolites. Therefore, in this work, we analyze the detection of pathogens transmitted through food and their metabolites using electrochemical biosensors based on nanomaterials.
Display omitted
•Globalization has contributed to the ease of transmission of foodborne pathogens.•Foodborne parasites, viruses, bacteria, and fungi represent a severe problem.•Detection studies using potentiometric biosensors have not been performed recently.•Electrochemical biosensors require conductive and semiconductor nanomaterials.•The study of carbon and metal nanocomposites will contribute to biosensors.
Display omitted
•Most food-borne contaminations are ascribable to microbial pathogens, their toxins, and herbicides.•The applicability of electrochemical biosensors against food toxins has been ...assessed.•Nanomaterial derived biosensors offer rapid and sensitive detection of food toxins.•Current advances in the detection techniques for food toxins have been described.•The review will aid in the development of superior electrochemical biosensors for food toxins.
There is a growing demand to protect food products against the hazard of microbes and their toxins. To satisfy such goals, it is important to develop highly sensitive, reliable, sophisticated, rapid, and cost-effective sensing techniques such as electrochemical sensors/biosensors. Although diverse forms of nanomaterials (NMs)-based electrochemical sensing methods have been introduced in markets, the reliability of commercial products is yet insufficient to meet the practical goal. In this review, we focused on: 1) sources of pathogenic microbes and their toxins; 2) possible routes of their entrainment in food, and 3) current development of NM-based biosensors to realize real-time detection of the target analytes. At last, future prospects and challenges in this research field are discussed.
Beef tallow significantly increases the thermal resistance of E. coli O157:H7, Salmonella spp., and L. monocytogenes. None of these microorganisms could survive such a long heating process at 75 °C ...in regular meat and poultry products.
Display omitted
•Beef tallow protected E. coli O157:H7, Salmonella spp., and L. monocytogenes during heating.•Survival curves showed two linearly declined patterns.•Survival curves were fitted to the Weibull model using one-step analysis.
The objective of this study was to evaluate the effect of fat on thermal resistance of L. monocytogenes, E. coli O157:H7, and Salmonella spp. A 4-strain cocktail of each microorganism was inoculated to beef tallow and heated isothermally at temperatures between 55 and 80℃. All survival curves did not follow the 1st-order inactivation kinetics but conformed to a two-stage linear pattern. The first stage was markedly less heat-resistant than the second, as manifested by significantly lower D values. The z values of E. coli O157 H7 and Salmonella spp. were 11.8 °C and 12.3 °C in the first stage (z1) but increased to 23.7 °C and 20.8 °C in the second stage (z2), respectively. For L. monocytogenes, while the z values were similar for both stages (z1 = 19.6 °C and z2 = 18.5 °C), the second stage D values are 3.6–5.9 times of those in the first stage. One-step analysis was used to fit the nonlinear curves to the Weibull model, yielding < 1 exponents for the model (0.495, 0.362, and 0.282, respectively, for L. monocytogenes, E. coli O157:H7, and Salmonella spp.), suggesting gradually increased thermal resistance during heating. The experimental results showed that these microorganisms could resist heating for longer time and at higher temperatures in tallow than they do in regular meats containing lower levels of fat. The kinetic models can be used to develop thermal processes to properly inactivate pathogens contaminated in the fat portions of meat products or other high fat products.
PDF
