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The draft genome of a previously documented potential probiotic Weissella cibaria strain GM93m3 from raw goat milk in Nigeria is reported. The total genome size was 2,447,229 with 46 contigs and G+C content of 44.86%., Competing Interests: The authors declare no conflict of interest.

Mycotoxins are toxic chemicals that adversely affect human health. Here, we assessed the influence of mycotoxin exposure on the longitudinal development of early life intestinal microbiota of Nigerian neonates and infants (NIs). Human biomonitoring assays based on liquid chromatography tandem mass spectrometry were applied to quantify mycotoxins in breast milk ( n = 68) consumed by the NIs, their stool ( n = 82), and urine samples ( n = 15), which were collected longitudinally from month 1-18 postdelivery. Microbial community composition was characterized by 16S rRNA gene amplicon sequencing of stool samples and was correlated to mycotoxin exposure patterns. Fumonisin B 1 (FB 1 ), FB 2 , and alternariol monomethyl ether (AME) were frequently quantified in stool samples between months 6 and 18. Aflatoxin M 1 (AFM 1 ), AME, and citrinin were quantified in breast milk samples at low concentrations. AFM 1 , FB 1 , and ochratoxin A were quantified in urine samples at relatively high concentrations. Klebsiella and Escherichia / Shigella were dominant in very early life stool samples (month 1), whereas Bifidobacterium was dominant between months 3 and 6. The total mycotoxin levels in stool were significantly associated with NIs' gut microbiome composition (PERMANOVA, p < 0.05). However, no significant correlation was observed between specific microbiota and the detection of certain mycotoxins. Albeit a small cohort, this study demonstrates that mycotoxins may influence early life gut microbiome composition.

A comprehensive study of bacterial and biotoxin contaminants of ready-to-eat (RTE) foods in Nigeria is yet to be reported. Hence, this study applied 16S rRNA gene sequencing and a dilute-and-shoot LC-MS/MS method to profile bacteria and biotoxins, respectively, in 199 RTE food samples comprising eko (n = 30) , bread (n = 30), shawarma (n = 35), aadun (n = 35), biscuits (n = 34), and kokoro (n = 35). A total of 631 bacterial isolates, clustered into seven operational taxonomic units, namely Acinetobacter , Bacillus , Klebsiella , Proteus and Kosakonia , Kurthia , and Yokenella , that are reported for the first time were recovered from the foods. One hundred and eleven metabolites comprising mycotoxins and other fungal metabolites, phytoestrogenic phenols, phytotoxins, and bacterial metabolites were detected in the foods. Aflatoxins, fumonisins, and ochratoxins contaminated only the artisanal foods ( aadun , eko, and kokoro ), while deoxynivalenol and zearalenone were found in industrially-processed foods (biscuit, bread, and shawarma), and citrinin was present in all foods except eko . Mean aflatoxin (39.0 µg/kg) in artisanal foods exceeded the 10 µg/kg regulatory limit adopted in Nigeria by threefold. Routine surveillance, especially at the informal markets; food hygiene and safety education to food processors and handlers; and sourcing of high-quality raw materials are proposed to enhance RTE food quality and safeguard consumer health.

Draft genomes of multidrug-resistant Shiga toxin-producing Escherichia coli (STEC) strains IPK9(1) and IKS1(2), which were isolated from ready-to-eat foods (kokoro and shawarma) sold in Lagos, Nigeria, are reported. The genomes possessed genetic determinants for virulence and the antibiotic resistance gene for macrolide-associated resistance mdf(A) . Ready-to-eat foods increase public health threats in Nigeria.

This study characterized the health risks due to the consumption of mycotoxin-contaminated foods and assessed the consumer awareness level of mycotoxins in households in two north-central Nigerian states during the harvest and storage seasons of 2018. Twenty-six mycotoxins and 121 other microbial and plant metabolites were quantified by LC-MS/MS in 250 samples of cereals, nuts and legumes. Aflatoxins were detected in all food types (cowpea, maize, peanut and sorghum) except in millet. Aflatoxin B 1 was the most prevalent mycotoxin in peanut (64%) and rice (57%), while fumonisin B 1 occurred most in maize (93%) and beauvericin in sorghum (71%). The total aflatoxin concentration was highest in peanut (max: 8422 µg/kg; mean: 1281 µg/kg) and rice (max: 955 µg/kg; mean: 94 µg/kg), whereas the totals of the B-type fumonisins and citrinin were highest in maize (max: 68,204 µg/kg; mean: 2988 µg/kg) and sorghum (max: 1335 µg/kg; mean: 186 µg/kg), respectively. Citrinin levels also reached 51,195 µg/kg (mean: 2343 µg/kg) in maize. Aflatoxin and citrinin concentrations in maize were significantly ( p < 0.05) higher during storage than at harvest. The estimated chronic exposures to aflatoxins, citrinin and fumonisins were high, resulting in as much as 247 new liver cancer cases/year/100,000 population and risks of nephrotoxicity and esophageal cancer, respectively. Children who consumed the foods were the most vulnerable. Mycotoxin co-occurrence was evident, which could increase the health risk of the outcomes. Awareness of mycotoxin issues was generally low among the households.

Grains and cassava-based foods serve as major dietary sources for many households in Nigeria. However, these foods are highly prone to contamination by moulds and aflatoxins owing to poor storage and vending practices. Therefore, we studied the fungal diversity in maize, cassava-based flour (pupuru), and rice vended in markets from Ondo state, Nigeria, and assessed their aflatoxin levels using an enzyme-linked immunosorbent assay. Molecular analysis of 65 representative fungal isolates recovered from the ground grains and pupuru samples revealed 26 species belonging to five genera: Aspergillus (80.9%), Penicillium (15.4%), and Talaromyces (1.9%) in the Ascomycota ; Syncephalastrum (1.2%) and Lichtheimia (0.6%) in Mucoromycota . Aspergillus flavus was the predominant species in the ground grains and pupuru samples. Aflatoxins were found in 73.8% of the 42 representative food samples and 41.9% exceeded the 10 μg/kg threshold adopted in Nigeria for total aflatoxins.

Animal milk types in sub-Saharan Africa (SSA) are processed into varieties of products using different traditional methods and are widely consumed by households to support nutritional intake and diet. Dairy products contain several microorganisms, their metabolites, and other chemical compounds, some with health benefits and many others considered as potential health hazards. Consumption of contaminated milk products could have serious health implications for consumers. To access the safety of milk products across SSA, studies in the region investigating the occurrences of pathogens as well as chemical compounds such as heat stable toxins and veterinary drug residues in animal milk and its products were reviewed. This is done with a holistic view in light of the emerging exposome paradigm for improving food safety and consumer health in the region. Herein, we showed that several published studies in SSA applied conventional and/or less sensitive methods in detecting microbial species and chemical contaminants. This has serious implications in food safety because the correct identity of a microbial species and accurate screening for chemical contaminants is crucial for predicting the potential human health effects that undermine the benefits from consumption of these foods. Furthermore, we highlighted gaps in determining the extent of viral and parasitic contamination of milk products across SSA as well as investigating multiple classes of chemical contaminants. Consequently, robust studies should be conducted in this regard. Also, efforts such as development cooperation projects should be initiated by all stakeholders including scientists, regulatory agencies, and policy makers to improve the dairy product chain in SSA in view of safeguarding consumer health., (© 2021 Institute of Food Technologists®.)

Despite the efforts to control mycotoxin contamination worldwide, extensive contamination has been reported to occur in food and feed. The contamination is even more intense due to climate changes and different stressors. This study examined the impact of fullerol C 60 (OH) 24 nanoparticles (FNP) (at 0, 1, 10, 100, and 1000 ng mL -1 ) on the secondary metabolite profile of the most relevant foodborne mycotoxigenic fungi from genera Aspergillus , Fusarium , Alternaria and Penicillium, during growth in vitro. Fungi were grown in liquid RPMI 1640 media for 72 h at 29 °C, and metabolites were investigated by the LC-MS/MS dilute and shoot multimycotoxin method. Exposure to FNP showed great potential in decreasing the concentrations of 35 secondary metabolites; the decreases were dependent on FNP concentration and fungal genus. These results are a relevant guide for future examination of fungi-FNP interactions in environmental conditions. The aim is to establish the exact mechanism of FNP action and determine the impact such interactions have on food and feed safety.

Deoxynivalenol (DON), one of the most abundant mycotoxins in cereal products, was recently detected with other mycotoxins and the emetic bacterial toxin cereulide (CER) in maize porridge. Within a cereal-based diet, co-exposure to these toxins is likely, hence raising the question of combinatory toxicological effects. While the toxicological evaluation of DON has quite progressed, consequences of chronic, low-dose CER exposure are still insufficiently explored. Information about the combinatory toxicological effects of these toxins is lacking. In the present study, we investigated how CER (0.1-100 ng/mL) and DON (0.01-10 µg/mL) alone and in a constant ratio of 1:100 (CER:DON) affect the cytotoxicity and immune response of differentiated human intestinal Caco-2 cells. While DON alone reduced cell viability only in the highest concentration (10 µg/mL), CER caused severe cytotoxicity upon prolonged incubation (starting from 10 ng/mL after 24 h and 48 h, 2.5 ng/mL and higher after 72 h). After 72 h, synergistic effects were observed at 2.5 ng/mL CER and 0.25 µg/mL DON. Different endpoints of inflammation were investigated in interleukin-1β-stimulated Caco-2 cells. Notably, DON-induced interleukin-8 transcription and secretion were diminished by the presence of 10 and 25 ng/mL CER after short-term (5 h) incubation, indicating immunosuppressive properties. We hypothesise that habitual consumption of cereal-based foods co-contaminated with CER and DON may cause synergistic cytotoxic effects and an altered immune response in the human intestine. Therefore, further research concerning effects of co-occurring bacterial toxins and mycotoxins on the impairment of intestinal barrier integrity, intestinal inflammation and the promotion of malnutrition is needed.

Ready-to-eat foods (RTEs) are foods consumed without any further processing. They are widely consumed as choice meals especially by school-aged children and the fast-paced working class in most low- and middle-income countries (LMICs), where they contribute substantially to the dietary intake. Depending on the type of processing and packaging material, RTEs could be industrially or traditionally processed. Typically, RTE vendors are of low literacy level, as such, they lack knowledge about good hygiene and food handling practices. In addition, RTEs are often vended in outdoor environments such that they are exposed to several contaminants of microbial origin. Depending on the quantity and type of food contaminant, consumption of contaminated RTEs may result in foodborne diseases and several other adverse health effects in humans. This could constitute major hurdles to growth and development in LMICs. Therefore, this review focuses on providing comprehensive and recent occurrence and impact data on the frequently encountered contaminants of microbial origin published in LMICs within the last decade (2009 to 2018). We have also suggested viable food safety solutions for preventing and controlling the food contamination and promoting consumer health., (© 2020 Institute of Food Technologists®.)

Across sub-Saharan Africa, chili peppers are fundamental ingredients of many traditional dishes. However, chili peppers may contain unsafe aflatoxin concentrations produced by Aspergillus section Flavi fungi. Aflatoxin levels were determined in chili peppers from three states in Nigeria. A total of 70 samples were collected from farmers' stores and local markets. Over 25% of the samples contained unsafe aflatoxin concentrations. The chili peppers were associated with both aflatoxin producers and atoxigenic Aspergillus flavus genotypes. Efficacy of an atoxigenic biocontrol product, Aflasafe, registered in Nigeria for use on maize and groundnut, was tested for chili peppers grown in three states. Chili peppers treated with Aflasafe accumulated significantly less aflatoxins than nontreated chili peppers. The results suggest that Aflasafe is a valuable tool for the production of safe chili peppers. Use of Aflasafe in chili peppers could reduce human exposure to aflatoxins and increase chances to commercialize chili peppers in premium local and international markets. This is the first report of the efficacy of any atoxigenic biocontrol product for controlling aflatoxin in a spice crop.

Infants are particularly susceptible toward the toxic effects of food contaminants, including mycotoxins. However, multimycotoxin exposure assessment in breast milk has received very limited attention so far, resulting in a poor understanding of coexposures during early life. Here, we present the development and application of a highly sensitive, specific, and quantitative assay assessing up to 28 mycotoxins, including regulated (aflatoxins, ochratoxin A, deoxynivalenol, zearalenone) and emerging mycotoxins as well as key metabolites by LC-MS/MS. After careful optimization of the sample preparation procedure, a QuEChERS protocol combined with a freeze-out step was validated in-house. The limits of quantification varied between 0.009 and 2.9 ng/mL, and for most analytes extraction recovery (74-116%) and intermediate precision (2-20%) were satisfactory. The method was applied to examine multiple breast milk samples obtained from 22 women ( n = 75 in total) from Ogun State, Nigeria. Most samples were either entirely free of mycotoxins or contaminated to a minimal extent with beauvericin (56%), enniatin B (9%), ochratoxin A (15%), and aflatoxin M 1 (1%). The most abundant mycotoxin was beauvericin, which was not reported in this biological fluid before, with concentrations up to 0.019 ng/mL. In conclusion, the method demonstrated to be fit for purpose to determine and quantify low background contaminations in human breast milk. On the basis of the high sensitivity of the novel analytical method, it was possible to deduce that tolerable daily intake values were not exceeded by breastfeeding in the examined infants.

Aspergillus flavus is the most important mycotoxin-producing fungus involved in the global episodes of aflatoxin B₁ contamination of crops at both the pre-harvest and post-harvest stages. However, in order to effectively control aflatoxin contamination in crops using antiaflatoxigenic and/or antifungal compounds, some of which are photosensitive, a proper understanding of the photo-sensitive physiology of potential experimental strains need to be documented. The purpose of the study is therefore to evaluate the effect of visible (VIS) light illumination on growth and conidiation, aflatoxin production ability and modulation of A. flavus oxidative status during in vitro experiment. Aflatoxigenic A. flavus strain was inoculated in aflatoxin-inducing YES media and incubated under three different VIS illumination regimes during a 168 h growth period at 29 °C. VIS illumination reduced A. flavus mycelia biomass yield, both during growth on plates and in liquid media, promoted conidiation and increased the aflatoxin production. Furthermore, aflatoxin production increased with increased reactive oxidative species (ROS) levels at 96 h of growth, confirming illumination-driven oxidative stress modulation activity on A. flavus cells., Competing Interests: The authors declare no financial or non-financial conflict of interest.