Control Of Foodborne Diseases Research Articles

Whole-genome comparative analysis of the genetic, virulence and antimicrobial resistance diversity of Campylobacter spp. from Spain

Whole-Genome Sequencing has the potential to be an effective method for surveillance and control of foodborne diseases. This study aims to determine the genetic relatedness and prevalence of virulence-associated genes and antimicrobial resistance determinants in 135 Campylobacter jejuni, seven Campylobacter coli and three Campylobacter lari isolates from the poultry supply chain and hospital in Spain. The isolates showed a wide genetic diversity between and within species with Clonal Complex 21 the most frequent lineage found. Among species, C. jejuni showed the highest prevalence of virulence genes (287/333) in which a high occurring variability was observed in the capsule biosynthesis and transport, O-linked flagellar glycosylation and lipooligosaccharide biosynthesis loci, with a great impact of phase-variation that led to 72 different virulence gene patterns among all isolates. High prevalence (> 90 %) of blaOXA-type β-lactamase genes and mutations in DNA gyrase gene associated with fluoroquinolones resistance were observed, and at a frequency similar to the tet(O) gene in C. jejuni (93 %) and C. coli (86 %), both of which also harboured resistance determinants to aminoglycosides with a higher occurrence rate in C. coli (43 %), that was the only species in which mutations in the 23S ribosomal subunit conferring resistance to erythromycin were identified (43 %). The present study constitutes the largest genomic survey of Campylobacter isolates in Spain providing insight into the prevalence and diversity of the pathogen along the poultry supply chain in the country.

Contamination Status and Serotypes Distribution of Salmonella in Food in Yantai City, China: A 14-Year Continuous Monitoring Study.

Salmonella is a foodborne zoonotic pathogen that threatens food safety and public health. However, few people have conducted long-term and systematic studies on Salmonella contamination in food in Yantai City. In order to investigate the situation of Salmonella contamination in food and improve the ability of early warning and control of foodborne diseases, a total of 3420 samples from 20 categories were collected from 13 monitoring points in Yantai City, from 2010 to 2023. The difference in detection rate and bacterial strain of different monitoring points, different types, and different sources of samples was compared. Of the 3420 samples, 80 were positive with a detection rate of 2.34%. Salmonella detection rates were significantly different for samples collected at different monitoring sites. Salmonella was detected only in meat and meat products and catering food, and none of the other types were detected. The detection rate of Salmonella was higher in raw animal meat and raw poultry. Samples collected at the market stage had the highest detection rate (5.81%), and there was a significant difference in detection rate between samples from different sources (χ2 = 36.93, p < 0.05). Eighty-one strains of Salmonella were detected out of 3420 samples (2 different strains were detected in 1 positive sample). The serological test identified 8 groups and 27 serotypes. The dominant serum groups were group B 30.86% (25/81), group E1 23.46% (19/81), and group D 16.05% (13/81). The main dominant serotypes were Salmonella give 17.28% (14/81), Salmonella enteritidis 16.05% (13/81), and Salmonella derby 13.58% (11/81). Meat and meat products and catering food were the main food products contaminated with Salmonella. The resulting secondary contamination is the hidden threat of foodborne diseases and should be given sufficient attention.

Isolation, Identification, Antimicrobial Resistance, Genotyping, and Whole-Genome Sequencing Analysis of Salmonella Enteritidis Isolated from a Food-Poisoning Incident.

Salmonella enterica is a common pathogen in humans and animals that causes food poisoning and infection, threatening public health safety. We aimed to investigate the genome structure, drug resistance, virulence characteristics, and genetic relationship of a Salmonella strain isolated from patients with food poisoning. The pathogen strain 21A was collected from the feces of patients with food poisoning, and its minimum inhibitory concentration against commonly used antibiotics was determined using the strip test and Kirby-Bauer disk methods. Subsequently, WGS analysis was used to reveal the genome structural characteristics and the carrying status of resistance genes and virulence genes of strain 21A. In addition, an MLST-based minimum spanning tree and an SNP-based systematic spanning tree were constructed to investigate its genetic evolutionary characteristics. The strain 21A was identified by mass spectrometry as S. enterica, which was found to show resistance to ampicillin, piperacillin, sulbactam, levofloxacin, and ciprofloxacin. The WGS and bioinformatics analyses revealed this strain as Salmonella Enteritidis belonging to ST11, which is common in China, containing various resistance genes and significant virulence characteristics. Strain 21A was closely related to the SJTUF strains, a series strains from animal, food and clinical sources, as well as from Shanghai, China, which were located in the same evolutionary clade. According to the genetic makeup of strain 21A, the change G > A was found to be the most common variation. We have comprehensively analyzed the genomic characteristics, drug resistance phenotype, virulence phenotype, and genetic evolution relationship of S. Enteritidis strain 21A, which will contribute towards an in-depth understanding of the pathogenic mechanism of S. Enteritidis and the effective prevention and control of foodborne diseases.

Microbial Composition and Diversity of High-demand Street-vended Foods in Ecuador

Developing countries such as Ecuador carry a heavy food safety burden but reports on the microbiological quality of their foods are scarce. In this investigation, the microbial diversity of 10 high-risk and mass-consumption street-vended foods including bolones, encebollado, food dressings, ceviche, chopped fruits, fruit juices, fruit salads, cheese, raw chicken, and ground beef in Quito, Guayaquil, and Cuenca, three major population centers in Ecuador, were evaluated using 16S rRNA gene High Throughput Sequencing. In total, 1,840 amplicon sequence variants (ASVs) were classified into 23 phyla, 253 families, 645 genera, and 829 species. In the tested food samples, Proteobacteria and Firmicutes were the most abundant phyla accounting for 97.41% of relative abundance (RA). At genus level, 10 dominant genera were identified: Acinetobacter (12.61% RA), Lactococcus (12.08% RA), Vibrio (8.23% RA), Weissella (7.43% RA), Aeromonas (6.18% RA), Photobacterium (6.32% RA), Pseudomonas (3.92% RA), Leuconostoc (3.51% RA), Klebsiella (3.49% RA), and Cupriavidus (2.86% RA). The highest microbial diversity indices were found in raw chicken, encebollados, fruit salads, and fruit juices from Guayaquil and Cuenca. From sampled foods, 29 species were classified as food spoilage bacteria and 24 as opportunistic pathogenic bacteria. Two groups associated with human diseases were identified, including 11 enteric species and 26 species of fecal bacteria. The occurrence of recognized and opportunistic pathogenic bacteria, as well as enteric and fecal microorganisms, in the street-vended foods indicated extensive risks for the consumers’ health. This study demonstrated the application of culture-independent amplicon sequencing in providing a more comprehensive view of microbial safety for street-vended food, which could be a useful tool to facilitate the control of foodborne diseases.

High diversity of Salmonella spp. from children with diarrhea, food, and environmental sources in Kilimanjaro - Tanzania: one health approach.

Salmonella is one of the most frequent causes of diarrhea globally. This study used a One Health approach to identify Salmonella species in children admitted with diarrhea and tested samples from the cases' household environment to investigate their genetic similarity using whole genome sequencing. Surveillance of hospitalized diarrhea cases among children under 5 years was conducted in rural and urban Moshi Districts in the Kilimanjaro Region of Tanzania from July 2020 through November 2022. Household visits were conducted for every child case whose parent/caregiver provided consent. Stool samples, water, domestic animal feces, meat, and milk were collected and tested for Salmonella. Isolates were sequenced on the Illumina NextSeq platform. Multilocus Sequence Typing and phylogenetic analyses were performed to map the genetic relatedness of the isolates. Salmonella was isolated from 72 (6.0%) of 1,191 samples. The prevalence of Salmonella in children with diarrhea, domestic animal feces, food, and water was 2.6% (n = 8/306), 4.6% (n = 8/174), 4.2% (n = 16/382), and 17.3% (n = 39/225), respectively. Four (1.3%) of the 306 enrolled children had a Salmonella positive sample taken from their household. The common sequence types (STs) were ST1208, ST309, ST166, and ST473. Salmonella Newport was shared by a case and a raw milk sample taken from the same household. The study revealed a high diversity of Salmonella spp., however, we detected a Salmonella clone of ST1208 isolated at least from all types of samples. These findings contribute to understanding the epidemiology of Salmonella in the region and provide insight into potential control of foodborne diseases through a One Health approach.

Rapid, on-site and yes-or-no detection of Salmonella typhimurium in foods using Argonaute-enabled assay

Early detection and control of foodborne diseases are crucial for ensuring food safety and consumer health. Therefore, there is a need for faster and more sensitive detection methods. We developed a rapid, portable and visible lateral flow biosensor (LFB) for foodborne pathogenic bacteria detection powered by a Pyrococcus furiosus Argonaute nuclease (PfAgo), named as PfAgo-LFB. LAMP (Loop-mediated isothermal amplification) was used to amplify the target nucleic acid. By using PfAgo as the “lighting up” technology, we can overcome the limitations of false-positive results and lack of effective endpoint monitoring in LAMP, greatly enhancing its applicability. It turned out that PfAgo-LFB was able to provide yes-or-no (positive or negative) results with a limit of detection (LOD) as low as 1 CFU/mL for S. typhimurium and the detection range was between 100 to 108 CFU/mL. It was able to secure a sample-to-answer test for contaminated food samples in less than 45 min and demonstrated satisfactory selectivity. In summary, we designed a PfAgo-LFB that rendered a novel, rapid, accurate, easy-to-deploy, on-site and yes or no detection of S. typhimurium, which could be generalized for building a “one-for-all” biosensing platform.

Use of whole genome sequencing for surveillance and control of foodborne diseases: status quo and quo vadis.

Improvements in sequencing quality, availability, speed and costs results in an increased presence of genomics in infectious disease applications. Nevertheless, there are still hurdles in regard to the optimal use of WGS for public health purposes. Here, we discuss the current state ("status quo") and future directions ("quo vadis") based on literature regarding the use of genomics in surveillance, hazard characterization and source attribution of foodborne pathogens. The future directions include the application of new techniques, such as machine learning and network approaches that may overcome the current shortcomings. These include the use of fixed genomic distances in cluster delineation, disentangling similarity or lack thereof in source attribution, and difficulties ascertaining function in hazard characterization. Although, the aforementioned methods can relatively easily be applied technically, an overarching challenge is the inference and biological/epidemiological interpretation of these large amounts of high-resolution data. Understanding the context in terms of bacterial isolate and host diversity allows to assess the level of representativeness in regard to sources and isolates in the dataset, which in turn defines the level of certainty associated with defining clusters, sources and risks. This also marks the importance of metadata (clinical, epidemiological, and biological) when using genomics for public health purposes.

Lateral Flow Strip Biosensors for Foodborne Pathogenic Bacteria via Direct and Indirect Sensing Strategies: A Review.

Rapid and sensitive detection of foodborne pathogenic bacteria is particularly important for the prevention and control of foodborne diseases. The lateral flow strip biosensor (LFSB) is one of the most promising point-of-care detection tools and has been widely used in food safety monitoring. This review introduces recent advances in the detection of foodborne pathogenic bacteria using LFSBs. According to different bacterial biomarkers, we summarize the direct and indirect sensing strategies of bacterial LFSBs. The direct sensing strategies for whole bacterial cells are divided into antibodies, antibody alternatives, and label-free according to the recognition elements. The indirect sensing strategies refer to the detection of bacterial nucleic acids and metabolites. Next, we compare and discuss the applications of direct and indirect sensing strategies. Finally, the existing challenges, future perspectives, and development directions are discussed, which will facilitate the theoretical innovation and practical application for bacterial LFSBs.

A Review of Modern Methods for the Detection of Foodborne Pathogens.

Despite the recent advances in food preservation techniques and food safety, significant disease outbreaks linked to foodborne pathogens such as bacteria, fungi, and viruses still occur worldwide indicating that these pathogens still constitute significant risks to public health. Although extensive reviews of methods for foodborne pathogens detection exist, most are skewed towards bacteria despite the increasing relevance of other pathogens such as viruses. Therefore, this review of foodborne pathogen detection methods is holistic, focusing on pathogenic bacteria, fungi, and viruses. This review has shown that culture-based methods allied with new approaches are beneficial for the detection of foodborne pathogens. The current application of immunoassay methods, especially for bacterial and fungal toxins detection in foods, are reviewed. The use and benefits of nucleic acid-based PCR methods and next-generation sequencing-based methods for bacterial, fungal, and viral pathogens' detection and their toxins in foods are also reviewed. This review has, therefore, shown that different modern methods exist for the detection of current and emerging foodborne bacterial, fungal, and viral pathogens. It provides further evidence that the full utilization of these tools can lead to early detection and control of foodborne diseases, enhancing public health and reducing the frequency of disease outbreaks.

Fluorescence sensing platform for Cronobacter sakazakii based on the cationic metal-organic frameworks modified upconversion nanoparticles

Cronobacter sakazakii ( C. sakazakii ) is a serious threat to human health. Efficient detection of C. sakazakii is crucial for food safety and the control of foodborne diseases. Here, a fluorescence sensing platform for C. sakazakii was constructed with α-glucosidase and cationic metal-organic framework-functionalized upconversion nanoparticles (UCNPs@MOFs). The anionic α-glucosidase was inhibited by binding to cationic UCNPs@MOFs. The presence of C. sakazakii competitively combined with cationic UCNPs@MOFs and released α-glucosidase into the enzyme substrate solution (para-nitrophenyl-α- d -glucopyranoside) to recover activity, thus triggering fluorescence quenching of cationic UCNPs@MOFs through the product of 4-nitrophenol. In addition, α-glucosidase from C. sakazakii accelerated the formation of 4-nitrophenol, thus improving the fluorescence response of cationic UCNPs@MOFs. This strategy illustrates high sensitivity of the designed platform for C. sakazakii with a wide linear range (1.1×10 2 –1.1 × 10 8 cfu mL −1 ), a low limit of detection (3.2 × 10 1 cfu mL −1 ), and an acceptable recovery value (85.2–111.5%) in real samples (tap water, infant formula powder, and goat milk powder). These results confirm that the proposed fluorescence platform is an ideal candidate tool for the detection of C. sakazakii in microbiological diagnostics. • A highly sensitive and rapid fluorescence sensor for Cronobacter sakazakii was developed. • The advantage of sensor based on the excellent fluorescence of functionalized upconversion nanoparticles probes. • The quenching was mainly arising from the competitive combination of UCNPs probes and the anionic enzyme. • A broad linear range (1.1×10 2 -1.1 × 10 8 cfu mL −1 ) and a high sensitivity (3.2 × 10 1 cfu mL −1 ). • Cronobacter sakazakii in real samples (tap water, infant formula powder and goat milk powder) were successfully detected.

Foodborne Diseases in the Edible Insect Industry in Europe-New Challenges and Old Problems.

Insects play a key role in European agroecosystems. Insects provide important ecosystem services and make a significant contribution to the food chain, sustainable agriculture, the farm-to-fork (F2F) strategy, and the European Green Deal. Edible insects are regarded as a sustainable alternative to livestock, but their microbiological safety for consumers has not yet been fully clarified. The aim of this article is to describe the role of edible insects in the F2F approach, to discuss the latest veterinary guidelines concerning consumption of insect-based foods, and to analyze the biological, chemical, and physical hazards associated with edible insect farming and processing. Five groups of biological risk factors, ten groups of chemical risk factors, and thirteen groups of physical risks factors have been identified and divided into sub-groups. The presented risk maps can facilitate identification of potential threats, such as foodborne pathogens in various insect species and insect-based foods. Ensuring safety of insect-based foods, including effective control of foodborne diseases, will be a significant milestone on the path to maintaining a sustainable food chain in line with the F2F strategy and EU policies. Edible insects constitute a new category of farmed animals and a novel link in the food chain, but their production poses the same problems and challenges that are encountered in conventional livestock rearing and meat production.

Engineering a SERS Sensing Nanoplatform with Self-Sterilization for Undifferentiated and Rapid Detection of Bacteria

The development of a convenient, sensitive, rapid and self-sterilizing biosensor for microbial detection is important for the prevention and control of foodborne diseases. Herein, we designed a surface-enhanced Raman scattering (SERS) sensing nanoplatform based on a capture-enrichment-enhancement strategy to detect bacteria. The gold-Azo@silver-cetyltrimethylammonium bromide (Au-Azo@Ag-CTAB) SERS nanotags were obtained by optimizing the synthesis process conditions. The results showed that the modification of CTAB enabled the nanotags to bind to different bacteria electrostatically. This SERS sensing nanoplatform was demonstrated to be fast (15 min), accurate and sensitive (limit of detection (LOD): 300 and 400 CFU/mL for E. coli and S. aureus, respectively). Of note, the excellent endogenous antibacterial activity of CTAB allowed the complete inactivation of bacteria after the assay process, thus effectively avoiding secondary contamination.

Improving Foodborne Disease Surveillance and Outbreak Detection and Response Using Peer Networks-The Integrated Food Safety Centers of Excellence.

Foodborne disease surveillance and outbreak investigations are foundational to the prevention and control of foodborne disease in the United States, where contaminated foods cause an estimated 48 million illnesses, 128 000 hospitalizations, and 3000 deaths each year. Surveillance activities and rapid detection and investigation of foodborne disease outbreaks require a trained and coordinated workforce across epidemiology, environmental health, and laboratory programs. Under the 2011 Food Safety Modernization Act, the Centers for Disease Control and Prevention (CDC) was called on to establish Integrated Food Safety (IFS) Centers of Excellence (CoEs) at state health departments, which would collaborate with academic partners, to identify, implement, and evaluate model practices in foodborne disease surveillance and outbreak response and to serve as a resource for public health professionals. CDC designated 5 IFS CoEs in August 2012 in Colorado, Florida, Minnesota, Oregon, and Tennessee; a sixth IFS CoE in New York was added in August 2014. For the August 2019-July 2024 funding period, 5 IFS CoEs were designated in Colorado, Minnesota, New York, Tennessee, and Washington. Each IFS CoE is based at the state health department that partners with at least one academic institution. IFS CoEs have built capacity across public health agencies by increasing the number of workforce development opportunities (developing >70 trainings, tools, and resources), supporting outbreak response activities (responding to >50 requests for outbreak technical assistance annually), mentoring students, and responding to emerging issues, such as changing laboratory methods and the COVID-19 pandemic.

A food systems approach and qualitative system dynamics model to reveal policy issues within the commercial broiler chicken system in South Africa.

Global broiler production and consumption levels continue to rise. South Africa’s broiler system is dominated by commercial production and formal retail trade, with competition from cheap imports. Local broiler policies have narrow, production-driven, short-term aims for industry growth and national food security. However, these have unintended consequences that undermine the system’s future sustainability. Using a food systems approach, this study developed a qualitative system dynamics model of the South African commercial broiler system and used it to engage stakeholders in policy discussions within the boundaries of health, nutrition, and environmental sustainability. A problem statement and key system elements were drawn from a previously published qualitative study and were validated by 15 stakeholders via an online questionnaire. From this, a seed model was developed, expanded into a larger model, and shared in a modular format with stakeholders in virtual meetings, on an individual or institutional basis, for feedback and validation, and for discussion of areas for policy consideration. Refinements were incorporated into the modules, policy considerations were summarised, and crosscutting issues were identified. The model demonstrated the system’s complexity, interlinkages, feedbacks, reinforcing and balancing loops, and behaviour archetypes. The modular presentation format created a suitable platform for stakeholder engagement. Current policies focus on local commercial production, formal markets, and affordability without cognisance of the broader system represented by the model. Inequality pervades throughout the system. Commercial producers, linked to large supermarkets and fast-food chains, dominate the system, presenting barriers to entry. Affordability is unintentionally traded off against non-communicable disease risks through brining of most frozen products, and ultra-processing of fast-food items. Foodborne disease control is critical, given the proportion of vulnerable individuals, and greater coherence of food safety policy is urgently needed. The environmental footprint of broilers, whilst less than that of ruminants, deserves closer scrutiny based on its dependence on intensive cereal production for feed. This study’s food systems approach provides a system-wide perspective and a foundation for policymakers to develop more integrated and transformative policies.

Bazı gıda kaynaklı patojenler üzerinde geleneksel yoğurt üretiminde kullanılan ticari starter kültürlerin ve probiyotiklerin antimikrobiyal etkisi

Objective: Although many techniques have been developed for food preservation, foodborne diseases are still an important problem. The studies aimed at solving this problem have increased in recent years using lactic acid bacteria with antimicrobial activities in foods. Materials and Methods: In this study, the antimicrobial effects of various lactic acid bacteria species, commercial yoghurt and probiotic yoghurt cultures and their supernatants on pathogen bacteria including Salmonella typmimurium NRLL E4463, Listeria monocytogenes Scott-A, Escherichia coli O157:H7, Staphylococcus aureus 6538P were examined by well diffusion and disc diffusion methods Results: It was determined that there were no statistical differences between the well diffusion and disc diffusion methods in terms of antimicrobial effects. It was also found that all of the lactic acid bacteria in MRS broth had substantial antimicrobial activities against the pathogens in both diffusion methods; however the antimicrobial effects of the supernatants obtained from cultures developed in media prepared from 10% skim milk powder showed diversity in terms of antimicrobial activity. Conclusion: These commercial cultures are thought to make a positive contribution with to help in the control of foodborne diseases.

Foodborne Disease Risk Prediction Using Multigraph Structural Long Short-term Memory Networks: Algorithm Design and Validation Study.

BackgroundFoodborne disease is a common threat to human health worldwide, leading to millions of deaths every year. Thus, the accurate prediction foodborne disease risk is very urgent and of great importance for public health management.ObjectiveWe aimed to design a spatial–temporal risk prediction model suitable for predicting foodborne disease risks in various regions, to provide guidance for the prevention and control of foodborne diseases.MethodsWe designed a novel end-to-end framework to predict foodborne disease risk by using a multigraph structural long short-term memory neural network, which can utilize an encoder–decoder to achieve multistep prediction. In particular, to capture multiple spatial correlations, we divided regions by administrative area and constructed adjacent graphs with metrics that included region proximity, historical data similarity, regional function similarity, and exposure food similarity. We also integrated an attention mechanism in both spatial and temporal dimensions, as well as external factors, to refine prediction accuracy. We validated our model with a long-term real-world foodborne disease data set, comprising data from 2015 to 2019 from multiple provinces in China.ResultsOur model can achieve F1 scores of 0.822, 0.679, 0.709, and 0.720 for single-month forecasts for the provinces of Beijing, Zhejiang, Shanxi and Hebei, respectively, and the highest F1 score was 20% higher than the best results of the other models. The experimental results clearly demonstrated that our approach can outperform other state-of-the-art models, with a margin.ConclusionsThe spatial–temporal risk prediction model can take into account the spatial–temporal characteristics of foodborne disease data and accurately determine future disease spatial–temporal risks, thereby providing support for the prevention and risk assessment of foodborne disease.

Microbial quality, physicochemical characteristics, proximate analysis, and antimicrobial activities of honey from Anfilo district

The physicochemical properties of honey depend on the type of plants used by honeybees during its preparation. The objectives of this study were to assess microbiological quality, physicochemical properties, proximate composition, and antimicrobial activities of honey. A total of twelve honey samples (three each from Koli, Shebel, Yali, and Yati sites) were collected from Anfilo district, Southwest Ethiopia. The mean microbial counts of all honey samples were below 4 Log CFU/g. Honey from the Yali site has recorded the lowest pH value (3.73 ± 0.04), the highest mean electric conductivities (0.89 ± 0.02 mS/cm), and ash content (0.64 ± 0.02 g/100 g). There were perfect positive correlation (r = 1.000, P < 0.01) between total solid content and water-soluble solid. Moreover, ash content showed a highly significant positive correlation with electric conductivity (r = 0.992, P < 0.01). Potassium contents of samples (mg/kg) ranged from 1121.67 ± 12.53 - 1259.33 ± 22.30 followed by calcium (93.33 ± 7.51 - 156.33 ± 9.45). Even though the concentration varies, honey from all sites inhibited the growth of all reference pathogens. Hence, honey is a good source of nutrients and has antimicrobial activities against foodborne pathogens. Further evaluation of honey as a nutritious therapeutic substance for the control of foodborne diseases is recommendable.

A novel photoelectrochemical aptamer sensor based on rare-earth doped Bi2WO6 and Ag2S for the rapid detection of Vibrio parahaemolyticus

In this work, layer-by-layer self-assembly method was used to construct the working electrode of the photoelectrochemical (PEC) aptamer sensor. Rare-earth doped Bi2WO6 (BWO-1) and Ag2S are combined as highly efficient photoactive material to reduce the recombination rate of electron-hole pairs and enhance the photocurrent responsiveness under visible light. The PEC aptamer sensor, with BWO-1 concentration of 12 mg/mL, AgNO3 concentration of 0.14 mol/L, ascorbicacid (AA) concentration of 0.13 mol/L, pH value of 7.4, aptamer concentration of 2 μmol/L, and incubation time of 50 min, had an optimal photocurrent responsiveness. The developed method showed a wide linear range from 3.2 × 102 CFU/mL to 3.2 × 108 CFU/mL. The detection limit was 40 CFU/mL. The constructed PEC aptamer sensor exhibited good detection specificity, stability and reproducibility for Vibrio parahaemolyticus and provided a simple, low-cost and rapid detection strategy for prevention and control of foodborne diseases. This method could be promising for the rapid detection of other food-bornepathogenicbacteria in the food.

Design and Development of an Instrument on Knowledge of Food Safety, Practices, and Risk Perception Addressed to Children and Adolescents from Low-Income Families

In the fight against foodborne diseases, expanding access to information for different groups is needed. In this aspect, it is crucial to evaluate the target audience’s particularities. This study constructed and validated an instrument containing three questionnaires to identify the level of knowledge, practices, and risk perception of food safety by low-income students between 11 and 14 years old. The following steps were used: systematic search of the databases; conducting and analyzing focus groups; questionnaires development; and questionnaires analysis. After two judges’ rounds, the final version was reached with 11 knowledge items, 11 practice items, and five risk perception items. The content validation index values were higher than 0.80. The adopted methodology considered the students’ understanding and perceptions, as well the appropriate language to be used. Besides, it allowed the development of questionnaires that directly and straightforwardly covers the rules set by the World Health Organization for foodborne disease control called Five Keys to Safer Food (keep clean; separate raw and cooked; cook thoroughly; keep food at safe temperatures; and use safe water and raw materials). Its use can result in a diagnosis for elaborating educational proposals and other actions against foodborne illness in the most vulnerable population.

Hemijski sastav etarskog ulja miloduha kultivara "Domaći ljubičasti" i ocena antimikrobne aktivnosti

Hyssop (Hyssopus officinalis L., Lamiaceae) is a perennial shrub or subshrub violet-blue flowers in verticillasters and spicy taste with a pungent flavour. Besides being used as a culinary herb for flavouring and food preservation, this plant is also an ornamental, bee attracting plant and a traditional remedy for respiratory diseases and digestive disturbances. Hyssop is an essential oil-bearing plant, and its essential oil (Hyssopi aetheroleum) is used in the pharmaceutical, perfume and cosmetics industries as well as in aromatherapy. The objective of this study was to determine the chemical composition of essential oil of hyssop CV. "Domaći ljubičasti", grown in Serbia, and investigate its antimicrobial activity against 16 bacteria, mainly pathogens in the food industry. A total of 61 compounds were detected in the hyssop essential oil. The bicyclic monoterpene ketones CIS-pinocamphone (43.8%) and trans-pinocamphone (18.3%) were the most abundant, comprising 62.1%, followed by b-pinene (6.3%) and pinocarvone (6.1%). Hyssop essential oil expressed antibacterial activity against: Staphylococcus aureus, Escherichia coli, Bacillus cereus, Proteus hauseri, Listeria monocytogenes, Rhodococcus equi, Listeria ivanovii, Salmonella Enteritidis, Enterococcus faecalis, Listeria innocua and Bacillus spizizenii. Hyssop essential oil did not express antibacterial activity against Pseudomonas aeruginosa, Salmonella Typhimurium, Klebsiella aerogenes and Staphylococcus epidermidis. Results of this study show that hyssop essential oil has potential for using as natural supplement for control of foodborne diseases of microbiological origin, as well as flavor compositions (herbaceous, camphor-like odour with warm and spicy undernotes), especially for meat products, sauces, soups and seasonings.