Bacteriological Quality and Biotoxin Profile of Ready-to-Eat Foods Vended in Lagos, Nigeria.

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 Genome Sequences of Multidrug-Resistant Shiga Toxin-Producing Escherichia coli O116:H25 Strains from Ready-to-Eat Foods Sold in Lagos, Nigeria.

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.

Microbiological safety of ready-to-eat foods in low- and middle-income countries: A comprehensive 10-year (2009 to 2018) review.

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.

Diversity and toxigenicity of fungi and description of Fusarium madaense sp. nov. from cereals, legumes and soils in north-central Nigeria.

Mycological investigation of various foods (mainly cowpea, groundnut, maize, rice, sorghum) and agricultural soils from two states in north-central Nigeria (Nasarawa and Niger), was conducted in order to understand the role of filamentous fungi in food contamination and public health. A total of 839 fungal isolates were recovered from 84% of the 250 food and all 30 soil samples. Preliminary identifications were made, based on macro- and micromorphological characters. Representative strains (n = 121) were studied in detail using morphology and DNA sequencing, involving genera/species-specific markers, while extrolite profiles using LC-MS/MS were obtained for a selection of strains. The representative strains grouped in seven genera (Aspergillus, Fusarium, Macrophomina, Meyerozyma, Neocosmospora, Neotestudina and Phoma). Amongst the 21 species that were isolated during this study was one novel species belonging to the Fusarium fujikuroi species complex, F. madaense sp. nov., obtained from groundnut and sorghum in Nasarawa state. The examined strains produced diverse extrolites, including several uncommon compounds: averantinmethylether in A. aflatoxiformans; aspergillimide in A. flavus; heptelidic acid in A. austwickii; desoxypaxillin, kotanin A and paspalitrems (A and B) in A. aflatoxiformans, A. austwickii and A. cerealis; aurasperon C, dimethylsulochrin, fellutanine A, methylorsellinic acid, nigragillin and pyrophen in A. brunneoviolaceus; cyclosporins (A, B, C and H) in A. niger; methylorsellinic acid, pyrophen and secalonic acid in A. piperis; aspulvinone E, fonsecin, kojic acid, kotanin A, malformin C, pyranonigrin and pyrophen in A. vadensis; and all compounds in F. madaense sp. nov., Meyerozyma, Neocosmospora and Neotestudina. This study provides snapshot data for prediction of food contamination and fungal biodiversity exploitation.