Food Poisoning Research Articles

Potential risk of biofilm-forming Bacillus cereus group in fresh-cut lettuce production chain

Bacillus cereus and Bacillus thuringiensis, which belong to the B. cereus group, are widely distributed in nature and can cause food poisoning symptoms. In this study, we collected 131 isolates belonging to the B. cereus group, comprising 124B. cereus and seven B. thuringiensis isolates, from fresh-cut lettuce production chain and investigated their potential risk by analyzing genotypic (enterotoxin and emetic toxin gene profiles) and phenotypic (antibiotic susceptibility, sporulation, and biofilm formation) characteristics. Enterotoxin genes were present only in B. cereus, whereas the emetic toxin gene was not detected in any of the B. cereus isolates. All isolates were susceptible to vancomycin, which is a last resort for treating B. cereus group infection symptoms, but generally resistant to β-lactam antimicrobials, and had the ability to form spores (at an average sporulation rate of 24.6 %) and biofilms at 30 °C. Isolates that formed strong biofilms at 30 °C had a superior possibility of forming a dense biofilm by proliferating at 10 °C compared to other isolates. Additionally, confocal laser scanning microscopy (CLSM) images revealed a notable presence of spores within the submerged biofilm formed at 10 °C, and the strengthened attachment of biofilm inner cells to the substrate was further revealed through biofilm structure parameters analysis. Collectively, our study revealed the prevalence and contamination levels of B. cereus and B. thuringiensis at fresh-cut lettuce production chain and investigated their genotypic and phenotypic characteristics, aiming to provide valuable insights for the development of potential risk management strategies to ensure food safety, especially along the cold chain.

Growth and no-growth boundary of Clostridium perfringens in cooked cured meats – A logistic analysis and development of critical control surfaces using a solid growth medium

This study was conducted to evaluate the effect of sodium nitrite (NaNO2, 100–200 ppm), sodium erythorbate (SE, 0–547 ppm), sodium tripolyphosphate (STPP, 0–0.5 %), and sodium chloride (NaCl, 2–3 %) on growth of C. perfringens using a solid growth medium and to develop a growth/no-growth boundary (critical control surface, or CCS) to prevent its growth in cooked cured meat under the optimal temperature condition. Melted Shahidi Ferguson Perfringens (SFP) agar, inoculated with a 3-strain spore cocktail and mixed with NaNO2, SE, STPP, and NaCl according to a Box-Behnken response surface experimental design, was dispersed in 96-well microplates and incubated anaerobically in an incubator programmed to remain at 4 °C for 24 h, heat to 80 °C in 1.75 h, quickly (0.5 h) cool to 46 °C (optimum temperature), and then maintain at 46 °C overnight. The plates were examined optically and visually for colony formation. Any well free of growth was designated as no-growth. Logistic regression was used to analyze the growth probability (P) as affected by NaNO2, SE, STPP, and NaCl and define a CSS as meeting the criterion of P < 1/96. The results showed that STPP and the interactions of SE with NaNO2 and NaCl could reduce the growth probability of C. perfringens in SFP agar. The validation of CCS with ground beef showed an accuracy of 96.3 % for no growth of C. perfringens in the inoculated samples. The results of this study proved that cured meat can be formulated with proper combinations of NaNO2, SE, STPP, and NaCl to prevent the growth of C. perfringens even under the optimum temperature condition, thus preventing food poisoning caused by the growth of this microorganism.

Assessment of Rhizopus rot control and quality attributes of manik chaman table grapes after post-harvest ozone and sodium metabisulfite treatment

An important fruit crop, grapes are vulnerable to fungal degradation, at different points, together with harvesting, post-harvest management, and storage. The effectiveness of ozone at concentrations 4416.6 L L-1, 6624.9 L L-1, &amp; 8833.2 L L-1 in combination with sodium metabisulfite (SMB), at concentrations of 50 mg, 70 mg, and 90 mg per 100 ml of potato dextrose broth (PDB) was investigated to solve this issue. Fumigation, and food poisoning techniques, were used in these treatments to stop R. stolonifer (Ehrenberg) Vuillemin’s radial growth. In a different trial, SMB in the forms of Indian, and African grape guards, as well as SMB powder packaged in pouches (at a rate of 0.5g per 500g of fruit), was examined, for its potential to combat Rhizopus rot in table grapes subjected to cold storage conditions (52 °C, RH-85-95%), over 49 days. The results showed that sodium metabisulfite at 90 mg/100 ml PDA, and ozone at 8833.2 l L-1 strongly reduced the radial growth of R. stolonifer by 94.82% and 98.14%, respectively. While the inoculation control registered 0.89 Disease Severity (DS), fruits treated with O3 and SMB showed, no symptoms of disease severity. Ozone at 7274.4 L L-1 &amp; 5455.8 L L-1 demonstrated, greater firmness retention of the berries (85.09 N; 84.82 N), as well as higher concentrations of ascorbic acid (3.90; 3.88 mg/100 g). Additionally, these treatments reduced, the levels of Total Soluble Solids (TSS) (18.68 N; 18.72 N), Percentage of Loss in Weight (PLW) (7.49; 7.55), and TSS/acid ratio (20.57 N; 21.52 N). In the sensory evaluation, these therapies received the highest overall acceptance ratings (8.04; 7.70). When combined with ozone, the application of SMB powder at a rate of 0.5g per 500g of grapes showed promising results, among the fruits that had been treated with SMB. In addition, compared to ozone, SMB treatments produced significantly higher L* and b* values. The highest L* value (40.53), highest b* value (23.77), and lowest a* value (-1.92) were all found with SMB powder at 0.5g/500g grapes. In conclusion, ozone shows promise in regulating Rhizopus rot effectively and keeping, the qualitative characteristics of table grapes, during cold storage, offering a feasible substitute, for sulfur dioxide treatments in conventional grape production.

Effectiveness of acetic and citric acid against Staphylococcus aureus contamination in parsley and dill

Staphylococcal food intoxication from Staphylococcus aureus (S. aureus) species is an important food-borne disease that threatens public health in many countries. Products prepared with fresh vegetables that have not been heat treated and/or not sufficiently disinfected are particularly risky. In this study, the effects of various organic acid (acetic and citric acid) concentrations on S. aureus previously inoculated into parsley and dill vegetables were investigated at storage time of 0, 1., 3., 5, and 7 days. For this purpose, a total of 7 groups were formed: individually with 0.5% and 1.5% acetic and citric acid, as well as their combinations and control. The number of S. aureus was adjusted to 102 and 106 (log CFU/mL) numbers that known to produce toxins by spectrophotometric method. As a result of the study, acetic and citric acid were found to be more effective when combined in S. aureus inhibition. It was observed that this effect varies depending on the microbiological load, acid concentration and storage days of the vegetables. It was also determined that the organic acids used had a better effect on the parsley than the dill vegetable.

Chemical Fungicides and Antagonists as Potential Treatments for Ganoderma lucidum-Associated Basal Stem Rot in Mandarin Trees

Ganoderma lucidum causes basal stem rot disease in mandarin trees, resulting in a variety of symptoms including dieback, foliage discoloration, an unhealthy appearance and eventual tree declines or death. Prior to field application, it is imperative to assess the efficacy of newer molecules and possible potential antagonists through In vitro testing. In this study, ten chemical fungicides and four antagonists were evaluated for their effectiveness against G. lucidum using the poison food method and dual culture technique, respectively. Among the chemical fungicides tested, Copper oxychloride 50% WP (@3g/l), Fluxapyroxad 167 G/L + Pyraclostrobin 333 G/L SC (@0.6 g/l), and Metiram 55% + Pyroclostribin 5% WG (@1g/l) demonstrated the highest effectiveness, entirely suppressing (100%) pathogen growth. In the dual culture technique, the fungal antagonists Trichoderma harzianum (79.63%) and Trichoderma asperellum (77.57%) exhibited superior effectiveness compared to Pseudomonas fluorescence and Bacillus subtilis against G. lucidum. These findings highlight the efficacy of chemical fungicides and antagonists in treating G. lucidum-induced basal stem rot in mandarin trees.

Compatibility of Commercial Polymers Used by the Seed Industry for Maize Biological Seed Coating

An efficient biological seed coating begins with the choice of a suitable polymer. Experiments were conducted at the Department of Seed Science and Technology, Professor Jayashankar Telangana State Agricultural University, Hyderabad, to determine the compatibility of commercial polymers and biocontrol agents. Five polymers commercially used by the seed industry were procured from seed companies. Three bioformulations were purchased from the commercial biofertilizer units and the pure cultures of Trichoderma viride, Pseudomonas fluorescens, and Bacillus subtilis were isolated from the bioformulations through serial dilutions, culturing and subculturing on microbial media. The compatibility of commercially used polymers has been tested with biocontrol agents using poisoned food technique (for fungal bioagents) and the inhibition zone technique (for bacterial bioagents). Observations on the reduction in radial growth of the fungal bioagent and zone of inhibition of bacterial bioagents was recorded in mm. The results revealed that all the 5 polymers commercially used by the seed industry were tested to show 96–100% compatibility with Trichoderma viride, 100% compatibility with Pseudomonas fluorescens, and 95–100% compatibility with Bacillus subtilis. These findings indicate that there is a greater compatibility of all the commercial polymers used in the seed industry with the bioagents which can also be used for effective seed coating with bioagents economically without incurring any additional inventory from the part of the industry.

Selection of Candidate Monoclonal Antibodies for Therapy of Botulinum Toxin Type A Intoxications.

Botulism is one of the most serious food intoxications, manifesting as prolonged paralytic conditions. This disease is usually the result of the consumption of poor quality canned or smoked foods, so the inhabitants of many countries of the world are exposed to the risk of this kind of poisoning every year. In view of the severity of poisonings caused by botulinum neurotoxins, monoclonal antibodies (mAbs) show great promise because of their targeting action, lack of allergic reactions and serum sickness. The use of a cocktail of mAbs increases the "functional specificity" of their mixture, allowing them to bind to the active domains of different toxin chains and block their action. In this work, we obtained 14 murine mAbs to the catalytic and receptor-binding domain of botulinum toxin type A. The Sp2/0-Ag14 murine myeloma cell line and splenocytes from immunized mice of the BALB/c line were used as fusion partners. We have shown that the selected cocktail of three antibodies neutralizes native toxin more effectively than antibodies separately-complete neutralization is achieved at a toxin dose of 3LD50 and partial neutralization at 5LD50. We presume that this cocktail may be promising as a prototype for the creation of a therapeutic drug capable of neutralizing the toxin in the blood of patients.

In vitro Assessment of Botanical Compatibility with Agaricus bisporus for Sustainable Disease Management

Button mushroom (Agaricus bisporus) cultivation is a significant aspect of the global mushroom industry, the production of fruiting bodies is severely affected by fungal, bacterial and viral pathogens that can have an effect on yield and quality. Botanicals, such as plant extracts, have been reported to possess various bioactive compounds with potential benefits for mushroom growth and disease control. A lab experiment was carried out in the Department of Plant Pathology, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj, Uttar Pradesh, to evaluate the compatibility of various botanicals viz., Allium sativum (garlic), Coriandrum sativum (coriander), Cuminum cyminum (jeera), Mentha spicata (pudina) with Agaricus bisporus in a Completely Randomised Design. In vitro evaluation was carried out using poison food technique at 10, 20 and 30% concentrations and 24, 48 &amp; 72 hours of incubation. The maximum radial growth of Agaricus bisporus was observed in T0-Control (Agaricus bisporus) (17.86 mm), (16.82 mm) and (16.53 mm) and minimum in T3- Cuminum cyminum (jeera) (2.23 mm), (0.98 mm) and (0.39 mm) at 10, 20 and 30 percent concentration respectively. Maximum percentage of inhibition was observed in T3 - Cuminum cyminum (jeera) (87.51 %), (94.11 %) and (98.24 %) at 10, 20 and 30 percent concentration respectively.

Using a DNA mini-barcode within the ITS region to identify toxic Amanita in mushroom poisoning cases

Mushroom poisoning contributes significantly to global foodborne diseases and related fatalities. Amanita mushrooms frequently cause such poisonings; however, identifying these toxic species is challenging due to the unavailability of fresh and intact samples. It is often necessary to analyze residues, vomitus, or stomach extracts to obtain DNA sequences for the identification of species responsible for causing food poisoning. This usually proves challenging to obtain usable DNA sequences that can be analyzed using conventional molecular biology techniques. Therefore, this study aimed to develop a DNA mini-barcoding method for the identification of Amanita species. Following the evaluation and optimization of universal primers for DNA mini-barcoding in Amanita mushrooms, we found that the internal transcribed spacer (ITS) gene sequence primer ITS-a was the most suitable DNA barcode primer for identifying Amanita species. Forty-three Amanita samples were subsequently amplified and sequenced. The sequences obtained were analyzed for intra- and inter-species genetic distances, and a phylogenetic tree was constructed. The findings indicated that the designed primers had strong universality among the Amanita samples and could accurately identify the target gene fragment with a length of 290 bp. Notably, the DNA mini-barcode accurately identified the 43 Amanita samples, demonstrating high consistency with the conventional DNA barcode. Furthermore, it effectively identified DNA from digested samples. In summary, this DNA mini-barcode is a promising tool for detecting accidental ingestion of toxic Amanita mushrooms. It may be used as an optimal barcode for species identification and traceability in events of Amanita-induced mushroom poisoning.Key points• Development of a DNA mini-barcoding method for Amanita species identification without fresh samples.• The ITS-a primer set was optimized for robust universality in Amanita samples.• The mini-barcode is suitable for screening toxic mushroom species in mushroom poisoning cases.Graphical

The biology and pathogenicity of Clostridium perfringens type F: a common human enteropathogen with a new(ish) name.

SUMMARYIn the 2018-revised Clostridium perfringens typing classification system, isolates carrying the enterotoxin (cpe) and alpha toxin genes but no other typing toxin genes are now designated as type F. Type F isolates cause food poisoning and nonfoodborne human gastrointestinal (GI) diseases, which most commonly involve type F isolates carrying, respectivefooly, a chromosomal or plasmid-borne cpe gene. Compared to spores of other C. perfringens isolates, spores of type F chromosomal cpe isolates often exhibit greater resistance to food environment stresses, likely facilitating their survival in improperly prepared or stored foods. Multiple factors contribute to this spore resistance phenotype, including the production of a variant small acid-soluble protein-4. The pathogenicity of type F isolates involves sporulation-dependent C. perfringens enterotoxin (CPE) production. C. perfringens sporulation is initiated by orphan histidine kinases and sporulation-associated sigma factors that drive cpe transcription. CPE-induced cytotoxicity starts when CPE binds to claudin receptors to form a small complex (which also includes nonreceptor claudins). Approximately six small complexes oligomerize on the host cell plasma membrane surface to form a prepore. CPE molecules in that prepore apparently extend β-hairpin loops to form a β-barrel pore, allowing a Ca2+ influx that activates calpain. With low-dose CPE treatment, caspase-3-dependent apoptosis develops, while high-CPE dose treatment induces necroptosis. Those effects cause histologic damage along with fluid and electrolyte losses from the colon and small intestine. Sialidases likely contribute to type F disease by enhancing CPE action and, for NanI-producing nonfoodborne human GI disease isolates, increasing intestinal growth and colonization.

Effects of pesticide residues on the growth and yield of vegetables at Navrongo of Ghana

BackgroundThe constant use of pesticides on farmlands is a source of food poison and potential cause of disease to humans in most parts of Africa. The lack of in-depth knowledge on the choices of use of the pesticides and their applications by most farmers in our African communities is a key to unsafe food and unhealthy living. Furthermore, the impact of some of these pesticides on the growth and yield of vegetable crops is largely unexplored. The present research was conducted in the Tono Irrigation Dam area of Navrongo, Ghana, where vegetable cultivation holds substantial economic importance making it a critical aspect of the local economy. In this study, we identified prevalent pesticides used in Navrongo’s vegetable cultivation, quantified pesticide residues present in selected vegetables grown, and assessed the impact of the pesticides on the vegetable crops’ growth and yields.MethodsThirty vegetable farmers at the Tono Irrigation Dam Area, Navrongo were randomly selected, and interviewed face to face. Questionnaires were also employed for data acquisition. Vegetables were sampled by dividing the farmland of each of the vegetable types in to three equal portions, and from each of the three portions, one sample was collected which was then put together with the other two samples as one. The samples were packed in zip-lock bags and kept at a cold temperature (− 20 ℃) before being transferred to the laboratory where they were thawed, homogenized and then subjected to extraction. The extract obtained was subjected to a clean-up process and then analyzed on a GC–MS instrument for pesticide detection and quantification.ResultsThe interview revealed number of years of farmers’ engagemrent in vegetable cultivation from one to ten, and identified four key vegetable varieties grown by the farmers: Capsicum annuum (pepper), Abelmoschus esculentus (okra), Solanum aethiopicum (garden egg) and Solanum lycopersicum (tomato). The data acquired gave identities or names of eight pesticides that are applied on the cultivated vegetables or farmlands by the farmers, and a decision on the vegetables selected for analysis in this study. Furthermore, the study revealed dichlorodiphenyltrichloroethane (DDT), k-optimal, lindane, and lambda-cyhalothrin to be among the pesticides in use, with DDT being a non-degradable, and the most widely applied pesticide. Notably, the DDT, lindane, and hexachlorocyclohexane, residues exceeded safety limits set by the European Commission in pepper, garden egg and okra. Unfortunately, banned pesticides such as heptachlor and aldrin were detected in the cultivated vegetables. More alarmingly, the commonly used DDT and lambda-cyhalothrin in the vegetable cultivation were found to hinder seed germination and seedling vigor in an investigation.ConclusionsThe DDT, lindane, and hexachlorocyclohexane, residues detected in the pepper, garden egg and okra samples that exceeded safety limits render these vegetables unsafe for human consumption. The banned heptachlor and aldrin detected in the vegetables indicate long-lasting environmental contamination. The commonly used DDT and lambda-cyhalothrin in the vegetable cultivation found to hinder seed germination and seedling vigor, indicate their non-degradability and substantial growth impediments. This present study therefore underscores the urgent need for enhanced safety measures and informs pesticide practices to safeguard both crops and public health in the district. We recommend further research be conducted to assess the potential health implications associated with the cultivation and consumption of vegetables in Navrongo, Ghana.

Salidroside Inhibits α-Amanitin-Induced AML-12 Cell Apoptosis via the Regulation of PINK1/Parkin-Mediated Mitophagy and Mitochondrial Function.

Poisoning caused by the mushroom Amanita phalloides, due to the toxin α-amanitin, accounts for approximately 90% of food poisoning deaths in China with no specific antidotes. To investigate the role of salidroside (Sal) in α-amanitin (α-AMA)-induced mitophagy, mouse liver cells AML-12 were exposed to α-AMA in the presence of Sal or not. Intracellular reactive oxygen species (ROS) levels were measured using a ROS detection kit, mitochondrial activity was evaluated using a mitochondrial red fluorescent probe kit or JC-1 dye, and protein expression levels of PINK1, Parkin, LC3 II, P62, Bax, Bcl-2, Caspase 3, Cleaved-Caspase 3, PARP I, and Cleaved-PARP I were detected through Western blot. Results demonstrated that α-AMA led to increased intracellular ROS levels, cell apoptosis, and decreased mitochondrial membrane potential. Notably, expression levels of mitophagy-related proteins PINK1, Parkin, and LC3 increased significantly while the P62 protein expression decreased remarkably. Furthermore, Sal reversed the α-AMA-induced decrease in cell viability and mitochondrial membrane potential and increase in intracellular ROS level. In addition, Sal promoted expression levels of PINK1, Parkin, and LC3 II while suppressing the Bax/Bcl-2 ratio, Cleaved-Caspase 3, and Cleaved-PARP I as well as P62. The results above proved that salidroside alleviates α-AMA-induced mouse liver cells damage via promoting PINK1/Parkin-mediated mitophagy and reducing cell apoptosis.

Acute gastroenteritis due to food poisoning in public spaces: A dissertation review

Acute gastroenteritis due to food poisoning in public spaces: A dissertation review

Reduction of the Cyanide from Cassava Leaves Using NaHCO3

Background: Cassava leaves are one part of the cassava plant, which can be consumed. Cassava leaves used as vegetable ingredients are weak as the presence of toxic cyanogenic glycosides. The pre-processing method of cassava leaves is performed to reduce the cyanide content. The method was modified using Sodium Bicarbonate (NaHCO3) substance, capable of binding cyanide acid, with stirring intervention from the stirrer chamber. This method is believed to contribute in lowering Hydrogen Cyanide (HCN) levels in a shorter period of time. The objective of this study was to assess the effectiveness of using NaHCO3 and a stirring chamber in decreasing the cyanide content of cassava leaves. Methods: A total of 48 samples were examined, all collected in June 2023. The assessment was based on comparing the NaHCO3 mass and the stirring time. The NaHCO3 mass was adjusted to 0, 10, 20, or 30 g with stirring times of 0, 15, 30, or 45 min. Cassava leaves are separated from the stalk and thoroughly washed then sliced 2 mm thick. Identification of cassava leaf HCN levels was measured using a spectrophotometer, wavelength 500 nm. The statistical variance analysis technique (ANOVA) was employed to detect the disparity in cyanide content among the cassava leaves of the various experimental groups. Results: The results indicated the highest cassava leaf HCN levels in the 0 g NaHCO3 group and the length of stirring time was 0 min, which was 217 ppm. The lowest cassava leaf HCN content in the group with the addition of 30 g NaHCO3 treatment with 150 rpm stirring is 56 ppm, with a percentage decrease of 32.5%. Conclusion: The finding of adding NaHCO3 and stirring cassava leaves in water is regarded as an effort to reduce HCN levels to prevent the risk of food poisoning.

Chemical Compositions, Phytochemical Screenings and Antifungal Activities of Cashew Nut Shell Liquid Extracts on Phytopathogenic Fungi of Yam (Dioscorea rotundata)

This study was carried out to evaluate the antifungal activity of Cashew (Anacardium occidentale L.) nutshell liquid on fungal pathogens of dry rot diseases of yam (Dioscorea cayennensis subsp. rotundata). The Soxhlet extraction method was used and constituents were identified and quantified using Gas chromatography. Isolation and identification of fungi complexes associated with dry rot disease of yam were made using Potato dextrose agar (PDA) as a medium. The antifungal activity of CNSL was evaluated using the food poisoning technique on PDA at 25, 50, 75 and 100% concentrations of CNSL dissolved in dimethyl sulphoxide. Azulene (57.65%) was the major chemical component of CNSL with phenolic compounds; anacardol, cresols and anacardic acid, among other compounds. CNSL phytochemical screening showed the presence of flavonoids, alkaloids, saponins, tannins, phenols, terpenoids, volatile oil and steroids. Infected yam tubers were isolated, four fungal strains (Fusarium solani, Lasiodiplodia theobromae, Aspergillus fumigatus, and A. niger) were identified, and pathogenicity test confirmed the association of the fungi species with the dry rot disease of white yam. CNSL was active against the identified fungi and could potentially compete with conventional standard as a suitable fungicide against dry rot disease of white yam.

Food byproduct-derived zinc-binding peptides: Dual suppression of planktonic and biofilm Staphylococcus aureus

With the increasing globalization of the food supply, foodborne infection and food poisoning brought by Staphylococcus aureus (S. aureus) have progressively become intractable issues. This work aimed to research the dual inhibitory effects of zinc-binding peptides (termed CSSP-Zn) on both planktonic and biofilm of S. aureus 6538, with respect to its utilization on pork models. Further research showed CSSP-Zn could disrupt the cytomembrane of permeability and integrity, triggering cytoplasm overflow, thereby causing proton motive force (PMF) collapse and metabolic disorder in planktonic strain 6538. The antibiofilm mechanism of CSSP-Zn primarily involved disrupting the expression of polysaccharide intercellular adhesion (PIA) biosynthesis-related genes (e.g. icaA, icaB, icaC and icaD), causing an enervated intercellular adhesion and lessened biofilm viability. When employed to a pork model, CSSP-Zn could obviously attenuate strain 6538 colonization and enterotoxin secretion. These results not only demonstrated the practical antibacterial efficacy of CSSP-Zn but also offered a novel strategy for mitigating the risk of S. aureus contamination in pork.

Rapid and accurate detection of foodborne pathogens: impedimetric immunosensor at the forefront

Microorganisms can be categorized into five categories: bacteria, algae, fungi, viruses, and protozoa which can cause microbiological hazards, contaminating food during production, manufacture, transportation, and storage. Biosensor technology is one of the most reliable and effective analytical technique for determining a biological system's sensitivity and specificity at a very low scale. So many techniques exist for identifying and detecting food-borne illness causing bacteria. But biosensor technology is used to detect and monitor with accuracy, thus increasing its interest globally with time. Biosensors have been used for a long time to illustrate the process of regulating data in the pharmaceutical, food manufacturing, and processing industries. An immunosensor is a type of biosensor that uses the molecular recognition specificity of antigens to form a stable complex of an antibody. It is divided into two subcategories- labeled and label-free. A labeled immunosensor is primarily used to sense the immune reaction and generate signals that allow versatile detection of complex, and detect the microorganisms like Listeria monocytogenes, Salmonella spp., and Escherichia coli. Label-free immunosensors detect physical changes during the immune complex formation and have been explored because of their potential as a specific detection technique which can reduce the time and cost of analysis. It has been developed using several detection methods like optical changes for Salmonella sp., electrochemical changes for Listeria monocytogenes and Escherichia coli, and Hepatitis B. An impedimetric immunosensor for pathogens has been created utilizing a biosensor, electrochemical impedance spectroscopy, antibodies, affinity proteins, affimers, and other binding proteins like bio-receptors, which exhibit good selectivity. This review discusses the techniques used by immunosensors to recognize microorganisms that might cause food poisoning. These techniques consider the electrodes and base-layer components, the makeup and characteristics of distinct bacterial species, as well as the interactions between antigens and antibodies that are utilized to detect bacteria.

Tetrodotoxin Derivatization with a Newly Designed Boron Reagent Leads to Conventional Reversed-Phase Liquid Chromatography.

Tetrodotoxin (TTX) is a representative natural toxin causing pufferfish food poisoning, which is especially prominent in East and Southeast Asia, including Japan. TTX has been analyzed through post-column derivatization high-performance liquid chromatography (HPLC), ion-pair LC-MS(/MS), and hydrophilic interaction liquid chromatography (HILIC)-MS(/MS) as alternatives to the mouse bioassay method. However, post-column derivatization requires a system for online derivatization reactions, and with the ion-pair LC-MS approach, it is difficult to remove residual ion-pair reagents remaining in the equipment. Moreover, HILIC-MS provides poor separation compared to reversed-phase (RP) HPLC and requires a long time to reach equilibration. Therefore, we decided to develop a TTX analytical method using pre-column derivatization and RP HPLC for the rapid assessment of outbreak samples, including food remnants. In this study, we focused on the vic-diol moiety of TTX and designed a new derivatization reagent coded as NBD-H-DAB. This NBD-H-DAB was synthesized from 4-hydrazino-7-nitro-2,1,3-benzoxadiazole (NBD-H) and 3-fluoro-2-formylphenylboronic acid (FFPBA) with a simple reaction system and rapidly converted to its boronate form, coded NBD-H-PBA, in an aqueous reaction solution. The NBD-H-PBA demonstrated appropriate hydrophobicity to be retained on the RP analytical column and successfully detected with a UV spectrometer. It was easily reacted with the vic-diol moiety of TTX (C6 and C11) to synthesized a boronic ester. The derivatized TTX could be detected using the RP HPLC-UV, and the limit of detection in the fish flesh samples was 0.06 mg/kg. This novel pre-column derivatization of TTX with NBD-H-PBA proves capable for the analysis of TTX.

Histamine-Responsive Hydrogel Biosensors Based on Aptamer Recognition and DNA-Driven Swelling Hydrogels.

Detection of chemical substances is essential for living a healthy and cultural life in the modern world. One type of chemical sensing technology, biosensing, uses biological components with molecular recognition abilities, enabling a broad spectrum of sensing targets. Short single-stranded nucleic acids called aptamers are one of the biological molecules used in biosensing, and sensing methods combining aptamers and hydrogels have been researched for simple sensing applications. In this research, we propose a hydrogel-based biosensor that uses aptamer recognition and DNA-driven swelling hydrogels for the rapid detection of histamine. Aptamer recognition and DNA-driven swelling hydrogels are directly linked via DNA molecular reactions, enabling rapid sensing. We selected histamine, a major food poisoning toxin, as our sensing target and detected the existence of histamine within 10 min with significance. Because this sensing foundation uses aptamers, which have a vast library of targets, we believe this system can be expanded to various targets, broadening the application of hydrogel-based biosensors.

Quality Control of Tap Water and Factors Determining Bacterial Contamination of Households’ Stored Drinking Water in the Town of Aboisso (Côte d’Ivoire)

Piped water must inspire consumer confidence in health and organoleptic terms. In the event of a food poisoning, consumers who have a poor perception of its quality may incriminate it, without taking into consideration that the fact of passing it through a drinking water storage container before consuming it can also cause contamination. The present study carried out in the town of Aboisso aimed to assess the role of water storage in the deterioration of microbiological quality of drinking water, and to identify the predictive factors of the presence of bacteria in stored water. To do this, physicochemical parameters (temperature, pH, conductivity, turbidity and free chlorine) and microbiological parameters (total coliforms, thermotolerant coliforms and &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt;) were measured on water samples taken from taps and storage containers in 94 households. The storage conditions of drinking water were also the subject of a brief household survey. The identification of predictive factors for the presence of total coliforms and &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt; in stored water was done using bivariate analysis and multivariate analysis by binary logistic regression through two models. The first model included the use of a transport container and the storage conditions as independent variables. The second included besides that the values of turbidity and free chlorine. As results, the waters were weakly mineralized and acidic. Free chlorine levels, temperature values, and bacterial loads in tap water were significantly (p &amp;lt; 0.05) higher than those in stored water. While 13.83% of samples taken at the taps were contaminated with total coliforms and 1.06% with &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt;, 50% and 18.09% of those taken in containers were contaminated with total coliforms and &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt;, respectively. In the first model, only the storage duration and the method used to draw water from storage container were statistically associated with the presence of total coliforms while no variable was statistically associated with the presence of &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt;. In the second model, the drawing method and the free chlorine level were significantly associated with the presence of total coliforms while only the free chlorine level was associated with &amp;lt;i&amp;gt;E. coli&amp;lt;/i&amp;gt;. These results motivate the need to raise awareness and train populations in drinking water hygiene.