Bacterial contaminants and their antibiotic susceptibility patterns in ready-to-eat foods vended in Ogun state,Nigeria

Contamination of ready-to-eat (RTE) foods by pathogenic bacteria may predispose consumers to foodborne diseases. This study investigated the presence of bacterial contaminants and their antibiotic susceptibility patterns in three locally processed RTE foods (eko, fufu and zobo) vended in urban markets in Ogun state, Nigeria. Bacteria isolated from a total of 120 RTE food samples were identified by 16S rRNA gene phylogeny while susceptibility patterns to eight classes of antibiotics were determined by the disc diffusion method. Species belonging to the genera Acinetobacter and Enterobacter were recovered from all RTE food types investigated, Klebsiella and Staphylococcus were recovered from eko and fufu samples, while those of Shigella were recovered from eko samples. Enterobacter hormaechei was the most prevalent species in all three RTE food types. Precisely 99% of 149 isolates were multidrug-resistant, suggesting a high risk for RTE food handlers and consumers. Co-resistance to ampicillin and cephalothin was the most frequently observed resistance phenotype. Results demonstrate that improved hygiene practices by food processors and vendors are urgently required during RTE processing and retail. Also, adequate food safety guidelines, regulation and enforcement by relevant government agencies are needed to improve the safety of RTE foods and ensure the protection of consumer health.     

Microbial diversity and prevalence of foodborne pathogens in cheap and junk foods consumed by primary schoolchildren

Aerobic plate counts (APC), coliforms, Bacillus cereus, Escherichia coli and eight foodborne pathogens were tested in 1008 cheap and junk foods, including candies, dried cakes, chewing gum, chocolate, dried and seasoned seafood, ice cream, and sugary foods. APCs were positive for 342 samples (33·9%), and the majority of the counts were 2–3 log CFU g^?1 or ml^?1 (average: 1·10 log CFU g^?1 or ml^?1). Most samples (97·3%) contained no coliforms (average: 0·07 log CFU g^?1 or ml^?1). Bacillus cereus was detected in 68 samples (average: 0·14 log CFU g^?1 or ml^?1). Escherichia coli and Listeria monocytogenes were detected in 6 and 1 samples, respectively, whereas other foodborne pathogens were not isolated. The highest bacterial counts were associated with dried and seasoned seafood products and dried cakes, suggesting that appropriate regulations of these food types should be considered. Cheap and junk foods were produced mainly in developing countries, but there were no significant differences in the bacterial counts among different countries of origin. The presence of foodborne pathogens may pose a risk for children. These results suggest that there is cause for deeper concern about the safety of these foods and that effective countermeasures should be established to improve their microbiological safety.

Significance and Impact of the Study

Food safety is especially important for children, but only limited information is available about the microbiological quality of cheap and junk foods that are consumed frequently by primary schoolchildren (e.g. dried cakes, candies and chocolates). The present study investigated the microbial quality of cheap and junk foods, and our results indicate that these foods are a potential health risk for children, therefore, deeper concern about the safety of these foods and effective countermeasures should be established to improve their microbiological safety. The present study may contribute to the development of an appropriate child food safety management system.     

Removing politics from innovations that improve food security

Genetically modified (GM) organisms and crops have been a feature of food production for over 30 years. Despite extensive science-based risk assessment, the public and many politicians remain concerned with the genetic manipulation of crops, particularly food crops. Many governments have addressed public concern through biosafety legislation and regulatory frameworks that identify and regulate risks to ensure human health and environmental safety. These domestic regulatory frameworks align to international scientific risk assessment methodologies on a case-by-case basis. Regulatory agencies in 70 countries around the world have conducted in excess of 4400 risk assessments, all reaching the same conclusion: GM crops and foods that have been assessed provide no greater risk to human health or the environment than non-GM crops and foods. Yet, while the science regarding the safety of GM crops and food appears conclusive and societal benefits have been globally demonstrated, the use of innovative products have only contributed minimal improvements to global food security. Regrettably, politically-motivated regulatory barriers are currently being implemented with the next genomic innovation, genome editing, the implications of which are also discussed in this article. A decade of reduced global food insecurity was witnessed from 2005 to 2015, but regrettably, the figure has subsequently risen. Why is this the case? Reasons have been attributed to climate variability, biotic and abiotic stresses, lack of access to innovative technologies and political interference in decision making processes. This commentary highlights how political interference in the regulatory approval process of GM crops is adversely affecting the adoption of innovative, yield enhancing crop varieties, thereby limiting food security opportunities in food insecure economies.

     

A Farm to Fork Risk Assessment for the Use of Wastewater in Agriculture in Accra,Ghana

The need to minimise consumer risk, especially for food that can be consumed uncooked, is a continuing public health concern, particularly in places where safe sanitation and hygienic practices are absent. The use of wastewater in agriculture has been associated with disease risks, though its relative significance in disease transmission remains unclear. This study aimed at identifying key risk factors for produce contamination at different entry points of the food chain. Over 500 produce and ready-to-eat salad samples were collected from fields, markets, and kitchens during the dry and wet seasons in Accra, Ghana, and over 300 soil and irrigation water samples were collected. All samples were analysed for E. coli, human adenovirus and norovirus using standard microbiological procedures, and real time RT-PCR. Finally, critical exposures associated with microbial quality of produce were assessed through observations and interviews. The study found that over 80% of produce samples were contaminated with E. coli, with median concentrations ranging from 0.64 to 3.84 Log E. coli/g produce. Prepared salad from street food vendors was found to be the most contaminated (4.23 Log E. coli/g), and that consumption of salad exceeded acceptable health limits. Key risk factors identified for produce contamination were irrigation water and soil at the farm level. Storage duration and temperature of produce had a significant influence on the quality of produce sold at markets, while observations revealed that the washed water used to rinse produce before sale was dirty. The source of produce and operating with a hygiene permit were found to influence salad microbial quality at kitchens. This study argues for a need to manage produce risk factors at all domains along the food chain, though it would be more effective to prioritise at markets and kitchens due to cost, ease of implementation and public health significance.     

Analysis of bacterial communities of three cassava-based traditionally fermented Nigerian foods (abacha,fufu and garri)

Globally, cassava is an important food crop that contributes significantly to food security. In Nigeria, cassava can be traditionally processed into abacha (fermented strips), fufu (submerged-fermented porridge) and garri (solid-state fermented farinated granules) for human consumption. Despite the widespread consumption of these foods, there is a major knowledge gap in understanding their core bacterial diversity. This study, therefore, applied next-generation sequencing of 16S rRNA gene to delineate the bacterial diversity in abacha, fufu and garri. Amplicon sequence variants belonging to nine phyla were present in the three foods. Firmicutes dominated the bacterial community of abacha and fufu, whereas, Proteobacteria was the dominant phylum in garri. At genus level taxa, Lactococcus, Lysinibacillus and Pseudomonas dominated the bacterial community in abacha, fufu and garri, respectively. Other dominant phylotypes reported in the foods belonged to Bacillus, Clostridium sensu stricto (cluster 1), Cupriavidus, Enterobacter, Sphingomonas and Staphylococcus. To the best of our knowledge, Clostridium sensu stricto cluster 1 and Lysinibacillus in fufu, and Brevundimonas, Cupriavidus, Sphingomonas and Strenotrophomomas in garri are reported for the first time. Although some potential pathogenic genera were recorded, the foods contained potentially functional species that could be explored to improve artisanal food production, food security and safeguard consumer health.     

High bioaccumulation of cadmium and other metals in Patagonian edible gastropods

High concentrations of metals are accumulated by edible marine resources, affecting human health. Marine gastropods have been commercially captured and consumed in Argentina for decades without official regulations or studies to guarantee their safety. In this study, metals (cadmium, aluminium, iron, zinc, copper and lead) were analysed for the first time in the edible marine gastropods Buccinanops globulosus, Adelomelon ancilla and Trophon geversianus and their surrounding sediments. Taking into account the maximum levels recommended by national and international regulations for food safety, we recommend consuming only the foot of these gastropod species. We recommend not consuming these gastropods from harbour areas due to concentrations of lead in sediments and tissues. Though the target hazard quotient (THQ) of cadmium was not high for the local community, it could be higher for other populations who consume molluscs more frequently, indicating a potential health risk of chronic exposure. Monitoring of these and other contaminants should be performed in order to ensure food safety of these marine resources.     

Public Reactions to Risk Messages Communicating Different Sources of Uncertainty: An Experimental Test

There is an abundant literature on the challenge of integrating uncertainties in experts’ risk assessments, but the evidence on the way they are understood by the public is scarce and mixed. This study aims to better understand the effect of communicating different sources of uncertainty in risk communication. A causal design was employed to test the effect of communicating risk messages varying in type of advisory warning (no risk and suggests no protective measure, or risk and recommends a protective measure) and sources of uncertainty (no uncertainty, divergence between experts, contradictory data, or lack of data) on public reactions. Participants from the general public (N = 434) were randomly assigned to read and react to variants of a fictitious government message discussing the presence of a new micro-organism found in tap water. Multiple analysis of variance showed that to report uncertainty from divergence between experts or from contradictory data reduced the adherence to the message, but not to mention the lack of data. Moreover, the communication of diverse sources of uncertainty did not affect trust in the government when the advisory warning stated there was a risk and recommended a protective measure. These findings have important implications for risk communication.     

Lycopene in Tomatoes: Chemical and Physical Properties Affected by Food Processing

ABSTRACT:?

Lycopene is the pigment principally responsible for the characteristic deep-red color of ripe tomato fruits and tomato products. It has attracted attention due to its biological and physicochemical properties, especially related to its effects as a natural antioxidant. Although it has no provitamin A activity, lycopene does exhibit a physical quenching rate constant with singlet oxygen almost twice as high as that of β-carotene. This makes its presence in the diet of considerable interest. Increasing clinical evidence supports the role of lycopene as a micronutri-ent with important health benefits, because it appears to provide protection against a broad range of epithelial cancers. Tomatoes and related tomato products are the major source of lycopene compounds, and are also considered an important source of carotenoids in the human diet. Undesirable degradation of lycopene not only affects the sensory quality of the final products, but also the health benefit of tomato-based foods for the human body. Lycopene in fresh tomato fruits occurs essentially in the all-trans configuration. The main causes of tomato lycopene degradation during processing are isomerization and oxidation. Isomerization converts all-trans isomers to cis-isomers due to additional energy input and results in an unstable, energy-rich station. Determination of the degree of lycopene isomerization during processing would provide a measure of the potential health benefits of tomato-based foods. Thermal processing (bleaching, retorting, and freezing processes) generally cause some loss of lycopene in tomato-based foods. Heat induces isomerization of the all-trans to cis forms. The cis-isomers increase with temperature and processing time. In general, dehydrated and powdered tomatoes have poor lycopene stability unless carefully processed and promptly placed in a hermetically sealed and inert atmosphere for storage. A significant increase in the cis-isomers with a simultaneous decrease in the all-trans isomers can be observed in the dehydrated tomato samples using the different dehydration methods. Frozen foods and heat-sterilized foods exhibit excellent lycopene stability throughout their normal temperature storage shelf life.

Lycopene bioavailability (absorption) can be influenced by many factors. The bioavailability of cis-isomers in food is higher than that of all-trans isomers. Lycopene bioavailability in processed tomato products is higher than in unprocessed fresh tomatoes. The composition and structure of the food also have an impact on the bioavailability of lycopene and may affect the release of lycopene from the tomato tissue matrix. Food processing may improve lycopene bioavailability by breaking down cell walls, which weakens the bonding forces between lycopene and tissue matrix, thus making lycopene more accessible and enhancing the cis-isomerization. More information on lycopene bioavailability, however, is needed. The pharmacokinetic properties of lycopene remain particularly poorly understood. Further research on the bioavalability, pharmacology, biochemistry, and physiology must be done to reveal the mechanism of lycopene in human diet, and the in vivo metabolism of lycopene.

Consumer demand for healthy food products provides an opportunity to develop lycopene-rich food as new functional foods, as well as food-grade and pharmaceutical-grade lycopene as new nutraceutical products. An industrial scale, environmentally friendly lycopene extraction and purification procedure with minimal loss of bioactivities is highly desirable for the foods, feed, cosmetic, and pharmaceutical industries. High-quality lycopene products that meet food safety regulations will offer potential benefits to the food industry.     

Real‐time subtyping via PFGE reveals potential epidemiological relatedness among human salmonellosis cases in Northern Italy

Aim: This study aimed to assess the applicability of a combined approach of traditional and molecular epidemiology in order to detect salmonellosis outbreaks in the Piedmont region (Italy), characterized by high Salmonella prevalence. Methods and Results: Pulsed field gel electrophoresis (PFGE) was used in real‐time and in combination with clinical surveillance to assess the relatedness of salmonellosis human cases; subsequently, PFGE profiles of clinical isolates were compared with those of isolates from food items collected during the same study period to identify putative food sources of Salmonella. The real‐time subtyping approach allowed the identification of an outbreak (21 isolates), which was undetected by epidemiological surveillance. Conclusions: Traditional epidemiological investigation did not allow the formulation of hypotheses on food items possibly associated with the outbreak owing mainly to patients’ difficulties in remembering foods they ate, and the tendency of health‐care professionals to direct patient’s suspicion towards specific food items. Significance and Impact of the Study: This finding highlighted the value of real‐time molecular subtyping in salmonellosis outbreak identification. In order to improve national epidemiological investigations implementing public health agency network and planning, information campaigns for health‐care professionals are required.     

Health Risk Assessment of Urban Surface Waters Based on Real-Time PCR Detection of Typical Pathogens

Typical enteric pathogens including enteroviruses, Salmonella typhi, Shigella spp., and Eschierichia coli were selected and monitored during a 1-year period in urban surface waters using the real-time polymerase chain reaction (PCR) method. By considering two routes of human exposure to urban surface waters (i.e., drinking water and involuntary intake), and supposing that the dose–response relation may follow either an exponential model or the Beta-Poisson model, health risk assessment was conducted to estimate the safety under a given acceptable risk level upon exposure to each water and to evaluate the required level of pathogen inactivation for safeguarding human health. As a result, it was found that human health risk due to enteroviruses is often greater than that due to bacterial pathogens, and greater removal of enteroviruses would be required for safeguarding at the same acceptable risk level.     

风险矩阵分级模型在哈尔滨市食品安全风险评估中的建立与应用

目的:建立哈尔滨市风险矩阵分级模型,并应用该模型探索食品污染的风险。方法:采用风险矩阵、文献综述及专家判断法对某年食品安全风险监测中位列化学污染物及微生物污染超标率首位的食品-项目组合,即动物肝脏-克伦特罗组合、水产品-副溶血性弧菌组合进行模型评估。结果:参照风险矩阵,动物肝脏-克伦特罗组合的健康风险分值为6,可以判断哈尔滨市人群由于食用动物肝脏而导致克伦特罗膳食暴露的健康风险等级为"中风险",水产品-副溶血性弧菌组合的健康风险分值为2,可以判断哈尔滨市人群每餐由于食用水产品而导致副溶血性弧菌膳食暴露的健康风险等级为"极低风险"。结论:哈尔滨市该年食品安全总体情况较好,风险等级较低,但部分监测项目存在食品安全风险隐患,应予以关注。     

Biofilms as a microbial hazard in the food industry: A scoping review

Biofilms pose a serious public health hazard with a significant economic impact on the food industry. The present scoping review is designed to analyse the literature published during 2001–2020 on biofilm formation of microbes, their detection methods, and association with antimicrobial resistance (if any). The peer-reviewed articles retrieved from 04 electronic databases were assessed using PRISMA-ScR guidelines. From the 978 preliminary search results, a total of 88 publications were included in the study. On analysis, the commonly isolated pathogens were Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., Escherichia coli, Bacillus spp., Vibrio spp., Campylobacter jejuni and Clostridium perfringens. The biofilm-forming ability of microbes was found to be influenced by various factors such as attachment surfaces, temperature, presence of other species, nutrient availability etc. A total of 18 studies characterized the biofilm-forming genes, particularly for S. aureus, Salmonella spp., and E. coli. In most studies, polystyrene plate and/or stainless-steel coupons were used for biofilm formation, and the detection was carried out by crystal violet assays and/or by plate counting method. The strain-specific significant differences in biofilm formation were observed in many studies, and few studies carried out analysis of multi-species biofilms. The association between biofilm formation and antimicrobial resistance was not clearly defined. Further, viable but non-culturable form of the foodborne pathogens is posing an unseen (by conventional cultivation techniques) but potent threat to the food safety. The present review recommends the need for carrying out systematic surveys and risk analysis of biofilms in food chain to highlight the evidence-based public health concerns, especially in regions where microbiological food hazards are quite prevalent.     

Ethnic differences in lifestyle and overweight in the Netherlands

Objective: To study the effects of lifestyle variables and socioeconomic status on overweight among native Dutch and immigrants in The Netherlands. Research Methods and Procedures: Data were used from a survey sample (N = 2551) of native Dutch and immigrant respondents (Surinamese/Antilleans, Turks, and Moroccans). BMI was calculated using self‐reported weight and height. Lifestyle variables such as modern food habits (take‐out food and eating out) and participating in sports were included, as well as socioeconomic and demographic background variables. Bivariate and ordinary least squares analyses were performed to study BMI and the determinants of overweight among the different groups. Results: All immigrant groups had a higher prevalence of overweight than the Dutch, except Moroccans. Men were overweight more frequently than women. Take‐out food, eating out, and fresh vegetables were related to a decrease in BMI, whereas convenience foods were related to an increase in BMI. For ready‐to‐eat meals, the results were mixed. In all groups, age was associated with a higher BMI, and a higher level of education was associated with a lower BMI. Immigrants participated in sports less frequently than native Dutch people. Discussion: One percent to 5% of the total public health costs can be attributed to costs for overweight‐related diseases. Public health policies should aim at stimulating healthy lifestyles and discouraging bad food habits through higher taxes on high‐calorie foods. In particular, Dutch immigrants should be encouraged to lose weight, because they have a higher risk for overweight‐related diseases.     

Current Perspectives on Issues in Risk Assessment Methods

The Office of Research and Development (ORD) of the U.S. Environmental Protection Agency was reorganized in 1995 to follow the risk assessment paradigm developed by the National Research Council. With the reorganization, a number of different research strategies and plans were developed on problem-driven topics (e.g., arsenic, particulate matter, and microbial pathogens/disinfectant byproducts) as well as on core research (e.g., ecological research, human health risk assessment research, and pollution prevention research). The human health risk assessments research strategy, which is currently under development, addresses a variety of issues which affect all human health risk assessments. These include mechanism of action, variation in response, aggregate risk, and effect on public health. While all of the issues that have been identified are important, the challenge to ORD is to identify which will have the greatest impact on improving risk assessment so that resources can be most strategically applied.     

Fuzzy rule-based Fine–Kinney risk assessment approach for rail transportation systems

Rail transportation is one of the most crucial public transportation types for big and crowded cities. In rail transportation systems, stakeholders face serious issues involved in workshops, stations, lines and their environments, and general office buildings. In order to reach an increased awareness and better occupational health and safety (OHS) management, a new risk assessment approach is proposed in this study. This approach includes a combination of Fine–Kinney method and a fuzzy rule-based expert system. It captures nonlinear causal relationships between Fine–Kinney parameters. Since there is a high level of vagueness involved in the OHS risk assessment data, the rule-based expert system is developed for probability (P), exposure (E), and consequence (C) for evaluating risk score. A case study is carried out in a rail transportation system in Istanbul/Turkey, and a comparison with the classical Fine–Kinney method is discussed. Results of the case study reveal risk clusters and corresponding control measures that should be taken into consideration. The study methodologically contributes to risk assessment in the knowledge, while case study in a real rail transportation system offers an insight into public transport industry in safety improvement.     

The development and status of Bt rice in China

Multiple lines of transgenic rice expressing insecticidal genes from the bacterium Bacillus thuringiensis (Bt) have been developed in China, posing the prospect of increases in production with decreased application of pesticides. We explore the issues facing adoption of Bt rice for commercial production in China. A body of safety assessment work on Bt rice has shown that Bt rice poses a negligible risk to the environment and that Bt rice products are as safe as non‐Bt control rice products as food. China has a relatively well‐developed regulatory system for risk assessment and management of genetically modified (GM) plants; however, decision‐making regarding approval of commercial production has become politicized, and two Bt rice lines that otherwise were ready have not been allowed to enter the Chinese agricultural system. We predict that Chinese farmers would value the prospect of increased yield with decreased use of pesticide and would readily adopt production of Bt rice. That Bt rice lines may not be commercialized in the near future we attribute to social pressures, largely due to the low level of understanding and acceptance of GM crops by Chinese consumers. Hence, enhancing communication of GM crop science‐related issues to the public is an important, unmet need. While the dynamics of each issue are particular to China, they typify those in many countries where adoption of GM crops has been not been rapid; hence, the assessment of these dynamics might inform resolution of these issues in other countries.     

Response Toward Novel Foods and Novel Objects in Wild Cebus apella

Animals respond to novel stimuli via explorative or neophobic behavior or both. The coexistence of these responses toward novel foods may be a successful adaptive strategy for a generalist species such as Cebus apella, because it allows the gradual introduction of new foods into the diet and reduces the risk of poisoning by ingestion of large amounts of toxic compounds (Glander, 1982; Milton, 1993; Visalberghi, 1994). Neophobia has been studied mostly in captivity. We investigated responsiveness to novelty in a group of 25–30 wild tufted capuchins (Cebus apella) in Iguazü National Park (Argentina). They had been habituated to visiting sites where bananas were provided on three elevated platforms. We presented novel stimuli on an adjacent platform. There were 4 experimental conditions with 10 sessions each: the Novel Food condition, the Novel Object condition, the Control condition, in which the platform was empty, and the Banana condition. In the Novel Food and Novel Object conditions, a new stimulus—food or object—was on the platform during each session. The Banana condition provided information on capuchin response to a familiar preferred food. Overall, capuchins were less responsive toward novel objects than toward novel foods; however, although cautious, they ate small amounts of the novel foods. Age affected individual responsiveness toward novel foods, whereas sex affected responsiveness toward novel objects. Capuchins ignored the empty platform. Our findings are in agreement with the idea that tufted capuchins can adapt to new habitats by gradually exploiting new food sources.     

Identification of Household Bacterial Community and Analysis of Species Shared with Human Microbiome

Microbial populations in indoor environments, where we live and eat, are important for public health. Various bacterial species reside in the kitchen, and refrigerators, the major means of food storage within kitchens, can be a direct source of food borne illness. Therefore, the monitoring of microbiota in the refrigerator is important for food safety. We investigated and compared bacterial communities that reside in the vegetable compartment of the refrigerator and on the seat of the toilet, which is recognized as highly colonized by microorganisms, in ten houses using high-throughput sequencing. Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes were predominant in refrigerator and toilet samples. However, Proteobacteria was more abundant in the refrigerator, and Firmicutes was more abundant in the toilet. These household bacterial communities were compared with those of human skin and gut to identify potential sources of household bacteria. Bacterial communities from refrigerators and toilets shared more species in common with human skin than gut. Opportunistic pathogens, including Propionibacterium acnes, Bacteroides vulgatus, and Staphylococcus epidermidis, were identified as species shared with human skin and gut microbiota. This approach can provide a general background of the household microbiota and a potential method of source-tracking for public health purposes.     

Virulence genes,antibiotic resistance and plasmid profiles of Enterococcus faecalis and Enterococcus faecium from naturally fermented Turkish foods

Aim: To determine the virulence genes, antibiotic resistance and plasmid profiles of 16 Enterococcus faecium and 68 Enterococcus faecalis strains isolated from various naturally fermented foods. Methods and Results: The presence of virulence genes (agg₂, gelE, cylM, cylB, cylA, espfs, espfm, efaAfs, efaAfm, cpd, cop, ccf, cad) and also the genes vanA and vanB were investigated by polymerase chain reaction (PCR). Antibiotic resistance of the isolates was determined by disc diffusion method. Most of the tested isolates were positive for virulence genes and resistant to some antibiotics. One of the Ent. faecalis strains isolated from a cheese sample carried the vanA gene and was intermediately resistant to vancomycin. The strains usually contained large plasmids, which might harbour acquired antibiotic resistance. Conclusion: The study showed that Ent. faecium and Ent. faecalis strains isolated from naturally fermented Turkish foods may be potential risk factors for consumer health in terms of virulence genes and acquired antibiotic resistance. Significance and Impact of the Study: The results indicate the importance of enterococcal contamination in terms of the safety of some fermented Turkish foods.