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In this study, melon (n = 60) and sesame (n = 60) seeds purchased from markets within Benue and Nasarawa states, respectively, in Nigeria, during two seasons (dry and wet), were analysed for fungal and mycotoxin contamination in order to determine the safety of these foods for human consumption. Molecular analysis revealed the following seven fungal taxonomic groups in the foods: Aspergillus section Candidi, Aspergillus section Flavi, Aspergillus section Nigri, Cladosporium, Fusarium fujikuroi species group, Penicillium, and Pleosporales/Didymellaceae. A total of 78 microbial metabolites, including several mycotoxins, occurred in the foods. The most frequent mycotoxins in melon and sesame were aflatoxin B1 (occurrence: 76%) and alternariol monomethyl ether (occurrence: 59%), respectively. However, higher mean total aflatoxin levels occurred in sesame (17 μg kg−1) than in melon (11 μg kg−1). About 28 and 5% of melon and sesame, respectively, exceeded the 4 μg kg−1 total aflatoxin limit for oilseeds intended for direct human consumption in the European Union. Additionally, fumonisin B1 and moniliformin occurred only in sesame, whilst ochratoxins A and B occurred only in melon; ochratoxin B being reported for the first time in this food. Our data indicated seasonal variations in the fungal and mycotoxin contamination levels in both foods.

There is scarce data on the mycotoxin profile in retailed fruit juices in Nigeria. Thirty-five industrially-processed fruit juice samples randomly purchased from retailers in Ogun state, Nigeria, were analysed for the presence of650 toxic fungal and plant metabolites using a liquid chromatography tandem mass spectrometric method. Only 18 metabolites, including 3-nitropropionic acid, alternariol methylether and emodin, but excluding citrinin, fumonisin B

The impact of fullerene C60 water soluble daughter molecules - fullerols C60(OH)24 nanoparticles (FNP) on emerging (non-aflatoxin biosynthetic pathway) toxins production in mycelia and yeast extract sucrose (YES) media of A. flavus was investigated under growth conditions of 29 °C in the dark for a 168 h period. The FNP solution (10, 100 and 1000 ng mL−1) contained predominantly nanoparticles of 8 nm diameter and with zeta potential mean value of −33 mV. Ten emerging metabolites were produced at concentrations reaching 1,745,035 ng 50 mL−1 YES medium. Seven of the metabolites were found in mycelia and media, while three were only in mycelia. Majority of the metabolites were detected in higher quantity in mycelia than in media, at a ratio of 99:1 (m/m). However, higher metabolite quantities were found in media following FNP application, while FNP caused a decrease of total metabolite quantities in mycelia. The concentrations of the metabolites in media increased in the presence of 1000 ng mL−1 FNP while mycelial quantities of the metabolites decreased with increased applied FNP dose. The impacts of global climate changes on FNP availability in the environment and on mycotoxin occurrence in crops increase the relevance of this study for risk assessment of nanoparticles. Cordycepin is reported for the first time as metabolite of A. flavus.

Exposure to food and environmental contaminants is a global environmental health issue. In this study, innovative LC-MS/MS approaches were applied to investigate mycotoxin co-exposure in mother-infant pairs (n = 23) by analyzing matched plate-ready food, breast milk and urine samples of mothers and their exclusively breastfed infants. The study revealed frequent co-occurrence of two to five mycotoxins. Regulated (e.g. aflatoxins, deoxynivalenol and ochratoxin A) and emerging mycotoxins (e.g. alternariol monomethyl ether and beauvericin) were frequently detected (3 %–89 % and 45 %–100 %), in at least one specimen. In addition, a moderate association of ochratoxin A in milk to urine of mothers (r = 0.47; p = 0.003) and infants (r = 0.52; p = 0.019) but no other significant correlations were found. Average concentration levels in food mostly did not exceed European maximum residue limits, and intake estimates demonstrated exposure below tolerable daily intake values. Infants were exposed to significantly lower toxin levels compared to their mothers, indicating the protective effect of breastfeeding. However, the transfer into milk and urine and the resulting chronic low-dose exposure warrant further monitoring. In the future, occurrence of mycotoxin-mixtures, and their combined toxicological effects need to be comprehensively considered and implemented in risk management strategies. These should aim to minimize early-life exposure in critical developmental stages.

The mycotoxicological safety of 85 mouldy dried fish (n=40) and meat (n=45) samples purchased from Ijebu-ode, Ogun State and Aleshinloye, Ibadan, Oyo State markets both in South Western part of Nigeria respectively, was assessed due to heavy consumption of these animal protein sources by many low-income families in Nigeria. The presence of aflatoxigenic moulds and levels of aflatoxins in the samples were determined by the dilution plating technique and high performance thin-layer chromatographic method. The predominant fungal species isolated from the samples was Aspergillus niger-clade (49.65%); other species isolated include Aspergillus section Flavi (36.83%) and (13.52%). All samples analysed for mycotoxin presence were contaminated with aflatoxin B1. Aflatoxin B2, G1 and G2 were below detectable limits. About 13% of the samples had aflatoxin B1 concentration higher than the maximum acceptable level (10 ng/g). Results imply that the consumption of mouldy dried meat can result in serious public health hazard and hence there is need for advocacy programs to enlighten the populace on proper processing and storage of meat products.

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 B1 was the most prevalent mycotoxin in peanut (64%) and rice (57%), while fumonisin B1 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 &lt, 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.

In this study, 81 samples of two cowpea varieties (brown: 54; white: 27) collected from various markets in southwestern Nigeria were examined for fungal and mycotoxin contamination. Moulds belonging to Aspergillus, Fusarium, and Penicillium were recovered from 99% of the samples. In both cowpea varieties, Aspergillus (52-53%) dominated Fusarium (29-30%) and Penicillium (17-20%). The interactive effect of cowpea variety and sampled location was significant (p = .013) on the occurrence of Fusarium species. Aflatoxins were detected in one brown and two white cowpea samples at concentrations reaching 209 and 84 µg/kg, respectively. Additionally, beauvericin was found in two samples of each cowpea variety, albeit at low concentrations. Cowpea presents as an alternative vegetable protein source to groundnuts in household nutrition with respect to mycotoxin contamination. Simple techniques to prevent mycotoxins in dry cowpeas are discussed.

Objective: To investigate the protective effect of aqueous leaf extract of Acalypha (A.) wilkesiana Muell. Arg (Euphorbiaceae) against cyclophosphamide-induced toxicity in albino rats. Methods: Twenty male albino rats were randomly divided into five groups of four animals each. The control group (I) was fed with pellets and distilled water, while group II was orally administered with only 20 mg/kg cyclophosphamide. Groups III, IV and V were co- administered with 20 mg/kg body weight cyclophosphamide and 110, 220 and 440 mg/kg body weight A. wilkesiana leaf extract, respectively, for 7 d. After treatment, liver and kidney function biomarkers, haematological parameters, liver antioxidants, and mitochondrial membrane permeability transition pore opening were investigated. Results: A. wilkesiana leaf extract significantly reduced (P

Ogi is a fermented cereal beverage, made primarily from maize (Zea mays) and rarely from millets. Unlike maize-based ogi, little is known about the bacterial community and mycotoxin profile during the production of millet-based ogi. Therefore, the bacterial community dynamics and mycotoxin reduction during ogi processing from three millet varieties were investigated using next-generation sequencing of the 16S rRNA gene and liquid chromatography-tandem mass spectrometry, respectively. A total of 1163 amplicon sequence variants (ASVs) were obtained, with ASV diversity across time intervals influenced by processing stage and millet variety. ASV distribution among samples suggested that the souring stage was more influenced by millet variety than the steeping stage, and that souring may be crucial for the quality attributes of the ogi. Furthermore, bacterial community structure during steeping and souring was significantly differentiated (PERMANOVA, P 0.05) between varieties, with close associations observed for closely-related millet varieties. Taxonomically, Firmicutes, followed by Actinobacteria, Bacteroidetes, Cyanobacteria and Proteobacteria phyla were relatively abundant (1%). Lactic acid bacteria, such as Burkholderia-Caballeronia-Paraburkholderia, Lactobacillus, Lactococcus and Pediococcus, dominated most fermentation stages, suggesting their roles as key fermentative and functional bacteria in relation to mycotoxin reduction. About 52-100%, 58-100% and 100% reductions in mycotoxin (aflatoxins, beauvericin, citrinin, moniliformin, sterigmatocystin and zearalenone) concentrations were recorded after processing of white fonio, brown fonio and finger millet, respectively, into ogi. This study provides new knowledge of the dominant bacterial genera vital for the improvement of millet-based ogi through starter culture development and as well, elucidates the role of processing in reducing mycotoxins in millet ogi.

BACKGROUND Infants are a vulnerable population whose nutrition changes as complementary foods are introduced; a process which may modify patterns of exposure to dietary mycotoxins. However, exposure monitoring of dietary mycotoxin mixtures in several biological samples obtained from breastfed and non-exclusively breastfed children is scarce. OBJECTIVES To examine mycotoxin co-exposure patterns in infants using a multi-specimen, multi-mycotoxin approach. METHODS Breast milk, complementary food and urine obtained from 65 infants, aged 1–18 months, in Ogun state, Nigeria, were analyzed for mycotoxins using ultra-sensitive LC-MS/MS approaches. RESULTS Complementary food was contaminated with seven distinct classes of mycotoxins including aflatoxins (9/42 samples; range: 1.0–16.2µg/kg) and fumonisins (14/42; range: 8– 167µg/kg). Aflatoxin M1 was detected in breast milk (4/22), while six other classes of mycotoxins were quantified; including dihydrocitrinone (6/22; range: 14.0–59.7ng/L) and sterigmatocystin (1/22; 1.2ng/L) detected for the first time. Mycotoxins were detected in 64/65 of the urine samples, with seven distinct classes of mycotoxins observed demonstrating ubiquitous exposure. Two aflatoxin metabolites (AFM1 and AFQ1) and FB1 were detected in 6/65, 44/65 and 17/65 samples, respectively. Mixtures of mycotoxin classes were common, including 14/42, 22/22 and 56/65 samples having 2–4, 2–6 or 2–6 mycotoxins present, for complementary food, breast milk and urine, respectively. Aflatoxin and/or fumonisin was detected in 12/14, 4/22 and 46/56 for complimentary foods, breast milk and urine, respectively. Furthermore, the detection frequency, mean concentrations and occurrence of mixtures were typically greater in urine of non-exclusively breastfed compared to breastfed children. CONCLUSIONS The study provides novel insights into mycotoxin co-exposures in children in a mycotoxin high-risk country without proper food safety measures. Albeit a small sample set, it highlights significant transition to higher levels of infant mycotoxin exposure as complementary foods are introduced, providing impetus to mitigate during this critical early-life period and encourage breastfeeding.

Background In Cameroon dietary staples are contaminated with diverse toxic fungal metabolites, known as mycotoxins. Aflatoxins and fumonisins are of particular public health concern, particularly in relation to cancer and/or early life stunting. Mixtures of these toxins are predicted from food measures, and in this work, the levels and frequencies of urinary mycotoxin biomarkers are reported in Cameroonian adults. Methods A single first void urine sample was collected from 89 adults (aged range: 28–85, male 39, female 50) from the city of Yaoundé, Centre Region, Cameroon. Urines were tested for eight distinct mycotoxins using measures of both parent compounds and/or their metabolites by Liquid Chromatography tandem mass spectrometry (LC-MS/MS). Results Altogether seven distinct mycotoxins, aflatoxin, fumonisin, deoxynivalenol, zearalenone, nivalenol, ochratoxin A and citrinin, (or their metabolites) were observed in urine samples. At least one mycotoxin was detected in all of the urine samples, 87 (97.8%) of which were above the method’s quantification limit. Aflatoxin M1 was detected in 42% (n.d. − 0.21 µg L− 1) of samples of which about a quarter additionally contained fumonisin B1. Of the remaining toxins deoxynivalenol, zearalenone, ochratoxin A, nivalenol and citrinin were present in 78%, 99% 95%, 53%, and 87% of the samples respectively. Alternariol was not detected in any sample. Mixtures of mycotoxins in the samples were frequently observed with 64 samples (72%) containing more than five mycotoxins. Estimates of intake exceeded the TDIs for fumonisin (n = 4), deoxynivalenol (n = 1) and zearalenone (n = 2), no TDI is set for aflatoxin. Conclusions This study reveals frequent co-exposure of Cameroonian individuals to a complex mixture of toxic and carcinogenic mycotoxins, with mixtures of aflatoxin and fumonisin a particular priority from a public health standpoint.

Low moisture content ready-to-eat foods vended in Nigerian markets could be pre-packaged or packaged at point of sale. These foods are widely and frequently consumed across Nigeria as quick foods. Despite their importance in the daily diets of Nigerians, a comprehensive study on the diversity of fungi, fungal metabolite production potential, and mycotoxin contamination in the foods has not yet been reported. Therefore, this study assessed the diversity of fungi in 70 samples of low moisture content ready-to-eat foods [cheese balls, garri (cassava-based), granola (a mix of cereals and nuts) and popcorn] in Nigeria by applying a polyphasic approach including morphological examination, genera/species-specific gene marker sequencing and secondary metabolite profiling of fungal cultures. Additionally, mycotoxin levels in the foods were determined by LC–MS/MS. Fungal strains (n = 148) were recovered only from garri. Molecular analysis of 107 representative isolates revealed 27 species belonging to 12 genera: Acremonium, Allophoma, Aspergillus, Cladosporium, Fusarium, Microdochium, Penicillium, Sarocladium, Talaromyces, and Tolypocladium in the Ascomycota, and Fomitopsis and Trametes in the Basidiomycota. To the best of our knowledge Allophoma, Fomitopsis, Microdochium, Tolypocladium, and Trametes are reported in African food for the first time. A total of 21 uncommon metabolites were found in cultures of the following species: andrastin A and sporogen AO1 in Aspergillus flavus; paspalin in A. brunneoviolaceus; lecanoic acid and rugulusovin in A. sydowii; sclerotin A in P. citrinum and Talaromyces siamensis; barceloneic acid, festuclavine, fumigaclavine, isochromophilons (IV, VI, and IX), ochrephilone, sclerotioramin, and sclerotiorin in P. sclerotium; epoxyagroclavine, infectopyron, methylorsellinic acid and trichodermamide C in P. steckii; moniliformin and sporogen AO1 in P. copticola; and aminodimethyloctadecanol in Tolypocladium. Twenty-four mycotoxins in addition to other 73 fungal and plant toxins were quantified in the foods. In garri, cheeseballs, popcorn and granola were 1, 6, 12, and 23 mycotoxins detected, respectively. Deoxynivalenol, fumonisins, moniliformin, aflatoxins and citrinin contaminated 37, 31, 31, 20, and 14% of all food samples, respectively. Overall, citrinin had the highest mean concentration of 1481 μg/kg in the foods, suggesting high citrinin exposures in the Nigerian populace. Fungal and mycotoxin contamination of the foods depend on pre-food and post-food processing practices.

Fungi and mycotoxin contamination of cocoa beans during fermentation and storage may constitute a hazard in the cocoa value chain and risk to consumers of its products. In this study, fungal profile and secondary metabolite patterns in two cocoa bean hybrids, F and T series, during fermentation and storage were determined. Additionally, secondary metabolite production by the recovered fungi in the beans was examined in culture media. Fungal isolates spanned six genera and eight species: Aspergillus niger, A. tamarii, Paecilomyces variotii, Penicillium citrinum, Pseudopithomyces palmicola, Simplicillium sp., Talaromyces atroroseus and Talaromyces sp.. In both hybrids, Aspergilli (38%) dominated the other fungi while more than one half of all the fungal isolates were from the beans in storage. Among the diverse secondary metabolites produced in media by the isolates were uncommon compounds, e.g. aspulvinone E produced by A. niger, aspterric acid by P. variotii, scalusamid A and sydowinin A by P. citrinum, norlichexanthone and siccanol by Simplicillium, and fallacinol and orsellinic acid by Talaromyces. The strains of P. citrinum produced up to 372 mg/kg citrinin. Forty-four fungal metabolites were quantified in both bean hybrids across the various processing stages, with about 86% occurring in the fermented beans stored for 30 days. The nephrotoxic citrinin, which was not previously reported in cocoa beans worldwide, was the only mycotoxin found in the fermented beans at overall mean concentration of 368 μg/kg. Additionally, its metabolite, dihydrocitrinone, was detected in fermented and stored beans. Consumption of freshly fermented cocoa beans may result in citrinin exposure. Appropriate fungal and mycotoxin control measures are proposed.

Exposure to natural food contaminants during infancy may influence health consequences later in life. Hence, breast milk may serve as a vehicle to transport these contaminants, including mycotoxins, from mothers to their infants. Analytical methods mostly focused on single exposures in the past, thus neglecting co-occurrences and mixture effects. Here, we present a highly sensitive multi-biomarker approach by a sophisticated combination of steps during sample preparation including a Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction followed by a solid phase extraction (SPE) cleanup and utilizing stable isotopes for compensating challenging matrix effects. The assay was validated in-house, reaching limits of detection (LOD) for all 34 analytes in the range of 0.1 to 300 ng/L with satisfying extraction efficiencies (75–109%) and stable intermediate precisions (1–18%) for most analytes. Compared to a similar multi-mycotoxin assay for breast milk, LOD values were decreased by a factor of 2–60x enabling the assessment of chronic low-dose exposures. The new method was applied to a small set of Nigerian breast milk samples (n = 3) to compare results with already published data. Concentration levels of samples that were found to be contaminated before could be confirmed. In addition, other mycotoxins were determined in all three samples, for example the newly investigated alternariol monomethyl ether (AME) was found for the first time in this biological fluid at concentrations up to 25 ng/L. Moreover, in a pooled Austrian sample obtained from a milk bank, trace amounts of multiple mycotoxins including AME (1.9 ng/L), beauvericin (5.4 ng/L), enniatin B (4.7 ng/L), enniatin B1 (

The mycotoxin profile of 135 raw milk samples from camel (n = 25), cow (n = 23) and goat (n = 87) in Nigeria was assessed by an ultra-sensitive LC-MS/MS method. Four, seven and 17 of the tested 36 mycotoxins were detected in camel, cow and goat milk, respectively. Among these were aflatoxin P1, alternariol monomethyl ether, citrinin, dihydrocitrinone, enniatins, ochratoxin α and sterigmatocystin reported for the first time in animal milk. The regulated aflatoxin M1 contaminated all cow milk (max: 81 ng/L) and 49% of goat milk (max: 3108 ng/L) samples, with 13% and 55%, respectively, exceeding the 50 ng/L EU limit. Aflatoxin M1 was not detected in camel milk samples. Overall, at least one mycotoxin was detected in 97% of all samples; beauvericin (87%) being the most frequent. Raw animal milk presents an additional source of mycotoxin exposures in the Nigerian populace. Consequently, mycotoxin mitigation should also target the dairy food chain.

The water soluble fullerene C60 daughter product - fullerols C60(OH)24 (FNP) possesses a great potential of modifying secondary metabolites biosynthesis. In order to clarify the extent of interaction, the impact of FNP (10, 100 and 1000 ng mL−1) on aflatoxin production and the available precursors of biosynthesis pathway from Aspergillus flavus NRRL 3251 was determined, in both the mycelia and yeast extract sucrose (YES) medium, during a 168-hour growth period at 29 °C in the dark. The FNP of 8 nm in diameter, and with a zeta potential of −33 mV affected mycelial growth at 1000 ng mL−1 while conidia production was slightly affected at 10 ng mL−1. The FNP effect on aflatoxin and it biosynthetic precursors was concentration dependent and alteration of the sterigmatocystin (ST) export from the cell was observed. Most of the monitored aflatoxin precursors, except norsolorinic acid, were detected in both mycelia and YES medium. However, observed precursor concentrations were much higher in mycelia, with exception of ST. The study shows the loss of FNP antioxidative effect after 120 hours of growth, and strong concentration dependent aflatoxigenic effect after that time. Thus, this data is relevant to guide future considerations on FNP-fungal interactions in the environments and on risk assessment.

The presence and reduction of multiple mycotoxins and metabolites during the processing of white and yellow maize varieties into ogi were determined by a robust liquid chromatography tandem mass spectrometric method. The levels of 16 mycotoxins and their metabolites were significantly reduced (on the average by 90%) by steeping (fermentation), draining the steep water/fermented-grain washing, and wet-milling/sieving. Mycotoxin reduction during ogi production from both maize varieties varied insignificantly by steeping duration; however, ogi from 48 h of steeping contained the least residual level of most mycotoxins. Whilst the nutritional parameters of ogi changed insignificantly based on steeping duration, yellow maize processed after 48 h of steeping yielded a product with better organoleptic properties than other ogi samples. This research provides highly relevant insights into the processing and safety of ogi considering the high dependence on this maize product by the populations in sub-Saharan Africa, especially children during their first 1000 days of life.

African traditional beverages are widely consumed food-grade liquids processed from single or mixed grains (mostly cereals) by simple food processing techniques, of which fermentation tops the list. These beverages are very diverse in composition and nutritional value and are specific to different cultures and countries. The grains from which home-processed traditional beverages are made across Africa are often heavily contaminated with multiple mycotoxins due to poor agricultural, handling, and storage practices that characterize the region. In the literature, there are many reports on the spectrum and quantities of mycotoxins in crops utilized in traditional beverage processing, however, few studies have analyzed mycotoxins in the beverages themselves. The available reports on mycotoxins in African traditional beverages are mainly centered on the finished products with little information on the process chain (raw material to final product), fate of the different mycotoxins during processing, and exposure estimates for consumers. Regulations targeting these local beverages are not in place despite the heavy occurrence of mycotoxins in their raw materials and the high consumption levels of the products in many homes. This paper therefore comprehensively discusses for the 1st time the available data on the wide variety of African traditional beverages, the mycotoxins that contaminate the beverages and their raw materials, exposure estimates, and possible consequent effects. Mycotoxin control options and future directions for mycotoxin research in beverage production are also highlighted.

Cereals, legumes and nuts are widely produced and consumed in Nigeria. Despite the availability of these food crops, their safety is often compromised by the presence of mycotoxins. In Nigeria, mixtures of several mycotoxins, including the highly carcinogenic aflatoxins together with fumonisins, ochratoxins and the trichothecenes, commonly co-occur in cereals and nuts than in legumes, thus, posing serious health risks to consumers. Physical interventions such as hand-sorting, cleaning/washing and other simple control measures (e.g., winnowing) could be effective to reduce mycotoxin exposures especially in resource-scarce rural areas. However, food crops are frequently stored prior to or after applying these measures. Hence, if storage conditions are inappropriate, other intervention strategies may fail due to increased accumulation of mycotoxins under poor storage. Moreover, poor storage practices may encourage infestation by insects and pests that can cause grain damage leading to contamination by toxigenic fungi. In addition, the market value of such grains will be adversely affected and this can contribute to economic loss and poverty at household level. This review provides data on mycotoxin contamination of grains in Nigeria, mycotoxins in biological fluids, and showcases various poor grain storage practices. Furthermore, viable alternatives for improved grain storage, which can be applied in Nigeria, were suggested as a means to reduce mycotoxin exposure and to safeguard consumer health.

The levels of mycotoxin contamination in 78 ear rot infected maize sampled from nine states of northern Nigeria were determined by a straight-forward LC-MS/MS-based ‘dilute and shoot’ approach. Overall, 93 metabolites were identified whereof most can be assigned either to Aspergillus or Fusarium toxins with 37 and 34% occurrence respectively. Fusarium toxins typically occurred in higher concentrations above 320,000 μg/kg for fumonisin B1 (FB1) and 1,000,000 μg/kg for hydrolysed FB1. The fumonisins (FB1, FB2 and FB4) were also most widespread, occurring in all samples. Aflatoxin B1 (mean: 800 μg/kg) was found in samples from all states, but in 63% of all samples. Less frequently reported aflatoxins (AFM1 and AFP1) were identified at a comparatively low level in the samples exhibiting the highest aflatoxin levels. Citrinin, cyclopiazonic acid, deoxynivalenol, nivalenol, ochratoxin A (OTA) and zearalenone also occurred in the samples. Total fumonisins, AFB1, total aflatoxin and OTA levels exceeded the EU limits in 76, 50, 47 and 1.3% of all samples respectively. The wide array of metabolites and exceptionally high concentrations of mycotoxins pose a substantial risk to food and feed safety in the event that the grains enter the animal and human food chain which is common in rural settings.

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&rsquo, 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.

Mycotoxins are secondary metabolites produced by various molds that contaminate many staple foods and cause a broad range of detrimental health effects in animals and humans through chronic exposure or acute toxicity. As such, the worldwide contamination of food and feed with mycotoxins is a significant problem, especially in sub-Saharan Africa. In this study, mycotoxin occurrence in staple foods consumed in Somalia was determined. A total of 140 samples (42 maize, 40 sorghum, and 58 wheat) were collected from a number of markets in Mogadishu, Somalia, and analyzed by a UPLC-MS/MS multimycotoxin method that could detect 77 toxins. All of the maize samples tested contained eight or more mycotoxins, with aflatoxin B1 (AFB1) and fumonisin B1 (FB1) levels reaching up to 908 and 17 322 μg/kg, respectively, greatly exceeding the European Union limits and guidance values. The average probable daily intake of fumonisins (FB1 and FB2) was 16.70 μg per kilogram of body weight (kg bw) per day, representing 835% of t...

Aflatoxins and ochratoxins are among the most important mycotoxins of all and producers of both types of mycotoxins are present inAspergillussectionFlavi, albeit never in the same species. Some of the most efficient producers of aflatoxins and ochratoxins have not been described yet. Using a polyphasic approach combining phenotype, physiology, sequence and extrolite data, we describe here eight new species in sectionFlavi. Phylogenetically, sectionFlaviis split in eight clades and the section currently contains 33 species. Two species only produce aflatoxin B1 and B2 (A. pseudotamariiandA. togoensis), and 14 species are able to produce aflatoxin B1, B2, G1 and G2: three newly described speciesA. aflatoxiformans, A. austwickiiandA. cerealisin addition toA. arachidicola,A. minisclerotigenes,A. mottae, A. luteovirescens(formerlyA. bombycis), A. nomius, A. novoparasiticus, A. parasiticus, A. pseudocaelatus, A. pseudonomius, A. sergiiandA. transmontanensis. It is generally accepted thatA. flavusis unable to produce type G aflatoxins, but here we report on Korean strains that also produce aflatoxin G1 and G2. One strain ofA. bertholletiuscan produce the immediate aflatoxin precursor 3-O-methylsterigmatocystin, and one strain ofAspergillus sojaeand two strains ofAspergillus alliaceusproduced versicolorins. Strains of the domesticated forms ofA. flavusandA. parasiticus,A. oryzaeandA. sojae, respectively, lost their ability to produce aflatoxins, and from the remaining phylogenetically closely related species (belonging to theA. flavus-,A. tamarii-,A. bertholletius- andA. nomius-clades), onlyA. caelatus,A. subflavusandA. tamariiare unable to produce aflatoxins. With exception ofA. togoensisin theA. coremiiformis-clade, all species in the phylogenetically more distant clades (A. alliaceus-,A. coremiiformis-,A. leporis- andA. avenaceus-clade) are unable to produce aflatoxins. Three out of the four species in theA. alliaceus-clade can produce the mycotoxin ochratoxin A:A. alliaceus s.str. and two new species described here asA. neoalliaceusandA. vandermerwei. Eight species produced the mycotoxin tenuazonic acid:A. bertholletius,A. caelatus, A. luteovirescens,A. nomius, A. pseudocaelatus,A. pseudonomius, A. pseudotamariiandA. tamariiwhile the related mycotoxin cyclopiazonic acid was produced by 13 species:A. aflatoxiformans, A. austwickii, A. bertholletius, A. cerealis, A. flavus, A. minisclerotigenes, A. mottae, A. oryzae, A. pipericola, A. pseudocaelatus,A. pseudotamarii, A. sergiiandA. tamarii. Furthermore,A. hancockiiproduced speradine A, a compound related to cyclopiazonic acid. SelectedA. aflatoxiformans, A. austwickii, A. cerealis, A. flavus, A. minisclerotigenes, A. pipericolaandA. sergiistrains produced small sclerotia containing the mycotoxin aflatrem. Kojic acid has been found in all species in sectionFlavi, exceptA. avenaceusandA. coremiiformis. Only six species in the section did not produce any known mycotoxins:A. aspearensis,A. coremiiformis, A. lanosus, A. leporis, A. sojaeandA. subflavus. An overview of other small molecule extrolites produced inAspergillussectionFlaviis given.

This study compared mycotoxin levels in 53 household-formulated and 84 industrially-processed complementary foods, assessed co-exposure patterns from consumption of the contaminated foods by infants and young children (IYC) in two Nigerian states, and evaluated the influence of awareness and adopted processing practices at the household levels on toxin levels in the foods. About 42 and 93% of the industrial- and household-processed foods, respectively, were contaminated by mycotoxins. Aflatoxins, alternariol, citrinin and dihydrocitrinone levels were significantly higher in household-formulated foods while fumonisins were similarly higher in the industrially-processed foods. Of the household-formulated items, Tom bran contained higher aflatoxin levels leading to higher exposure (median: 641 ng/kg bw per day) and health risk (β-coefficient: 51.4; p = 0.01) in the IYC. Family cereal and ogi contained the highest levels of fumonisins in the industrial and household food categories, respectively, with the highest exposure estimated for IYC who consumed family cereal (median: 18 μg/kg bw per day). Aflatoxin exposures were higher in children aged 12–24 months compared to those below 12 months of age. About 69 and 75% of IYC who consumed family cereal and Tom bran, respectively, were co-exposed to mycotoxins resulting in commensurate risks of co-exposures. Overall, 47% of the IYC were co-exposed to 2–4 mycotoxins (aflatoxins, citrinin, fumonisins and ochratoxin A) with eight different co-exposure combinations. Only 33% of the respondents were aware of mycotoxins. Length of grain storage influenced food aflatoxin levels. Adequate risk management advice to concerned stakeholders for mycotoxin control in complementary foods in Nigeria is offered herein.

Kunu is a traditional fermented single or mixed cereals-based beverage popularly consumed in many parts of West Africa. Presently, the bacterial community and mycotoxin contamination profiles during processing of various kunu formulations have never been comprehensively studied. This study, therefore, investigated the bacterial community and multi-mycotoxin dynamics during the processing of three kunu formulations using high-throughput sequence analysis of partial 16S rRNA gene (hypervariable V3-V4 region) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. A total of 2,303 operational taxonomic units (OTUs) were obtained across six processing stages in all three kunu formulations. Principal coordinate analysis biplots of the Bray-Curtis dissimilarity between bacterial communities revealed the combined influences of formulations and processing steps. Taxonomically, OTUs spanned 13 phyla and 486 genera. Firmicutes (phylum) dominated (relative abundance) most of the processing stages, while Proteobacteria dominated the rest of the stages. Lactobacillus (genus taxa level) dominated most processing stages and the final product (kunu) of two formulations, whereas Clostridium sensu stricto (cluster 1) dominated kunu of one formulation, constituting a novel observation. We further identified Acetobacter, Propionibacterium, Gluconacetobacter, and Gluconobacter previously not associated with kunu processing. Shared phylotypes between all communities were dominated by lactic acid bacteria including species of Lactobacillus, Lactococcus, Leuconostoc, Pediococcus, and Weissella. Other shared phylotypes included notable acetic acid bacteria and potential human enteric pathogens. Ten mycotoxins [3-Nitropropionic acid, aflatoxicol, aflatoxin B 1 (AFB 1 ), AFB 2 , AFM 1 , alternariol (AOH), alternariolmethylether (AME), beauvericin (BEAU), citrinin, and moniliformin] were quantified at varying concentrations in ingredients for kunu processing. Except for AOH, AME, and BEAU that were retained at minimal levels of < 2 μg/kg in the final product, most mycotoxins in the ingredients were not detectable after processing. In particular, mycotoxin levels were substantially reduced by fermentation, although simple dilution and sieving also contributed to mycotoxin reduction. This study reinforces the perception of kunu as a rich source of bacteria with beneficial attributes to consumer health, and provides in-depth understanding of the microbiology of kunu processing, as well as information on mycotoxin contamination and reduction during this process. These findings may aid the development of starter culture technology for safe and quality kunu production.

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 &deg, 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.

An examination of the mould and fungal metabolite pattern in melon and bush mango seeds locally produced in Nigeria was undertaken in order to understand the mycotoxicological risk posed to consumers of both of these important and commonly consumed soup thickeners. The variation in mycotoxin levels in graded categories of both foodstuffs were also determined. Aspergillus, Fusarium, Penicillium, Mucorales and Trichoderma were the recovered fungi from the foodstuffs with Aspergillus species dominating (melon=97.8%; bush mango=89.9%). Among the Aspergillus species identified Aspergillus section Flavi dominated (melon: 72%; bush mango: 57%) and A. flavus, A. parasiticus, A. parvisclerotigenus and A. tamarii were the recovered species. About 56% and 73% of the A. flavus isolates from melon and bush mango seed samples, respectively were aflatoxigenic. Thirty-four and 59 metabolites including notable mycotoxins were found in the melon and bush mango seeds respectively. Mean aflatoxin levels (μg/kg) in melon (aflatoxin B1 (AFB1)=37.5 and total aflatoxins=142) and bush mango seeds (AFB1=68.1 and total aflatoxins=61.7) were higher than other mycotoxins, suggesting potential higher exposure for consumer populations. Significantly (p

Human breast milk is considered as the best and ideal form of nutrition for infants. However, food contaminants such as mycotoxins, which may be transferred from maternal blood to milk, are poorly described. Mycotoxins are a major group of natural toxins frequently detected in foods. Here, we review the current state-of-the-art in the monitoring of mycotoxins in human breast milk, i.e., knowledge on occurrence, metabolism, and analytical assays utilized for their quantification. We highlight that most of the data captured to date have not been verified with the precision now capable utilizing LC-MS/MS and LC-HRMS approaches. One concern is that some studies may overestimate individual measures, and most cannot capture the patterns and levels of mycotoxin mixtures. We propose accurate assessment as a priority, especially for aflatoxins, fumonisins, ochratoxin A, zearalenone, and deoxynivalenol as well as their major metabolites. However, also so-called emerging toxins such as citrinin, the enniatins, beauvericin, aurofusarin, or Alternaria toxins should be considered to evaluate their potential relevance. Key requirements for analytical quality assurance are identified and discussed to guide future developments in this area. Moreover, research needs including investigations of lactational transfer rates, the role of human metabolism for bioactivation or detoxification, and an evaluation of potential combinatory effects of different mycotoxins are pointed out. It is hoped that LC-MS based multianalyte methods will enable more accurate, rapid and affordable human biomonitoring approaches that support informed decisions for maternal and infant health.

In order to understand the changes in toxic metabolite profiles in uncooked and cooked foods, samples of flour/grain (n = 40) and their corresponding plate-ready food (n = 39) were collected from 40 households in two states of northern Nigeria. The food samples were analyzed for multiple fungal metabolites by LC-MS/MS and daily intakes of mycotoxins in the diets were estimated and compared to established margin of exposure (MOE) and tolerable daily intake (TDI) values. Both food groups contained 65 fungal and plant metabolites, inclusive of 23 mycotoxins. The mean concentrations of aflatoxin B1, beauvericin, fumonisin B1 (FB1), FB2, FB3, hydrolysed FB1, moniliformin and nivalenol were significantly (p < 0.05) higher in flour than in the plate-ready food samples. The levels of several mycotoxins were higher in the flour samples than in plate-ready meals by 129–383%. The dilution effect from proportionate mixing of flour samples with water led to 48–100% reduction in detectable mycotoxins in flour to plate-ready meals. Aflatoxins and fumonisins co- occurred in 36% of the plate-ready foods. Exposures of households to aflatoxins and fumonisins based on 95% CI concentration of mycotoxins in the meals were high, suggesting potential health risks based on calculated low MOE and exceedence of stipulated TDI value, respectively.

There is a critical need to better understand the patterns, levels and combinatory effects of exposures we are facing through our diet and environment. Mycotoxin mixtures are of particular concern due to chronic low dose exposures caused by naturally contaminated food. To facilitate new insights into their role in chronic disease, mycotoxins and their metabolites are quantified in bio-fluids as biomarkers of exposure. Here, we describe a highly sensitive urinary assay based on ultra-high performance liquid chromatography - tandem mass spectrometer (UHPLC-MS/MS) and 13C-labelled or deuterated internal standards covering the most relevant regulated and emerging mycotoxins. Utilizing enzymatic pre-treatment, solid phase extraction and UHPLC separation, the sensitivity of the method was significantly higher (10-160x lower LODs) than in a previously described method used for comparison purpose, and stable isotopes provided compensation for challenging matrix effects. This method was in-house validated and applied to re-assess mycotoxin exposure in urine samples obtained from Nigerian children, adolescent and adults, naturally exposed through their regular diet. Owing to the methods high sensitivity, biomarkers were detected in all samples. The mycoestrogen zearalenone was the most frequently detected contaminant (82%) but also ochratoxin A (76%), aflatoxin M1 (73%) and fumonisin B1 (71%) were quantified in a large share of urines. Overall, 57% of 120 urines were contaminated with both, aflatoxin M1 and fumonisin B1, and other co-exposures were frequent. These results clearly demonstrate the advanced performance of the method to assess lowest background exposures (pg mL−1 range) using a single, highly robust assay that will allow for the systematic investigation of low dose effects on human health.

Consumption of mycotoxin contaminated foodstuffs is common in regions where foods are not adequately controlled and routinely monitored, and this could have adverse effects on the health of consumers. In this study, 100 samples of roasted nuts (50 cashew nuts and 50 peanuts) vended within two cities of Sierra Leone were analysed for mycotoxins and other microbial metabolites by a LC-MS/MS method. The peanut samples contained detectable levels of 17 microbial metabolites, including aflatoxins B

Mycotoxins are toxic secondary fungal metabolites that can negatively affect animal productivity when ingested through feed. In order to assess mycotoxin contamination of poultry feed and feed ingredients vis-a-vis source tracking of feed contamination in Nigeria, 102 samples of feed (n = 30) and feed ingredients (n = 72) were collected from in-house mills of poultry farms across 12 states of Nigeria and analyzed for multiple mycotoxins using LC/MS-MS. One hundred and forty microbial metabolites were detected in the feed and feed ingredients. The most frequent mycotoxin in the feed was fumonisin B1, occurring in 97% of the samples at mean concentration of 1014 μg kg−1. AFB1 occurred in 83% of the feed samples at mean concentration of 74 μg kg−1 and in all feed ingredients except fish meal and other cereals (millet and rice). Feed samples analyzed in this study were contaminated with at least four mycotoxins: aflatoxins and fumonisin co-occurring in 80% of the samples. Peanut cake and maize contributed the most to the levels of aflatoxin and fumonisin, respectively, in the feed. Consequently, there is a need to explore other cereal- and protein-based ingredients for compounding feeds in order to reduce the risk associated with high mycotoxin (e.g. aflatoxin) intake in poultry. Electronic supplementary material The online version of this article (10.1007/s12550-018-0337-y) contains supplementary material, which is available to authorized users.

Liquid chromatography (LC) coupled with mass spectrometry (MS) is widely used for the determination of mycotoxins in cereals and cereal-based products. In addition to the regulated mycotoxins, for which official control is required, LC–MS is often used for the screening of a large range of mycotoxins and/or for the identification and characterization of novel metabolites. This review provides insight into the LC–MS methods used for the determination of co-occurring mycotoxins with special emphasis on multiple-analyte applications. The first part of the review is focused on targeted LC–MS approaches using cleanup methods such as solid-phase extraction and immunoaffinity chromatography, as well as on methods based on minimum cleanup (quick, easy, cheap, effective, rugged, and safe; QuEChERS) and dilute and shoot. The second part of the review deals with the untargeted determination of mycotoxins by LC coupled with high-resolution MS, which includes also metabolomics techniques to study the fate of mycotoxins in plants. Electronic supplementary material The online version of this article (10.1007/s00216-017-0750-7) contains supplementary material, which is available to authorized users.

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 M1 (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.

This study assessed, for the first time, the mycotoxicological risks from consumption of complementary foods by infants and young children in Nigeria. Molds belonging to Aspergillus aculeatinus, A. flavus, A. luchuensis, A. tubingensis, A. welwitschiae and Geotrichum candidum were recovered from the complementary foods. Twenty-eight major mycotoxins and derivatives, and another 109 microbial metabolites including chloramphenicol (a bacterial metabolite), were quantified in 137 food samples by LC-MS/MS. Aflatoxins and fumonisins co-contaminated 42% of the cereal- and nut-based food samples, at mean concentrations exceeding the EU limits of 0.1 and 200 μg/kg set for processed baby foods by 300 and six times, respectively. Milk contained mainly beauvericin, chloramphenicol and zearalenone. The trichothecenes, T-2 and HT-2 toxins, were quantified only in infant formula and at levels three times above the EU indicative level of 15 μg/kg for baby food. Chronic exposure estimate to carcinogenic aflatoxin was high causing low margin of exposure (MOE). Exposures to other mycotoxins either exceeded the established reference values by several fold or revealed low MOEs, pointing to important health risks in this highly vulnerable population. The observed mycotoxin mixtures may further increase risks of adverse health outcomes of exposure; this warrants urgent advocacy and regulatory interventions.

This study reports the fungal and bacterial metabolites associated with natural contamination of 38 composite samples of locally processed rice from five Agro-ecological Zones of Nigeria (AEZs). The samples were evaluated for the presence of microbial metabolites with the Liquid Tandem Mass Spectrometry (LC-MS/MS) technique. Among the identified metabolites, 63 fungal and 5 bacterial metabolites were measured at varying concentrations and occurrence levels. Fusarium toxins had the highest incidence of 79% but occurred in low amounts with fumonisin B1 (FB1) having the highest percentage incidence of 39.5% and a mean of 18.52 µg/kg. Among the Aspergillus toxins, aflatoxins (AFs) occurred in 36.9% of the rice samples with aflatoxin B1 (AFB1) having the highest occurrence level of 18.4% and a mean value of 5 µg/kg. About 12 metabolites had incidence levels >50%, including beauvericin (BEA) and tryptophol which had occurrence levels of 100%. Among the emerging toxins under evaluation by international organizations such as the European Food Safety Authority (EFSA) and the Food and Agriculture Organization of the United Nations (FAO), citrinin, sterigmatocystin (STER) and beauvericin were detected with maximum values of 207, 125 and 131 ?g/kg respectively. This paper also reports the first documented evidence of the contamination of Nigerian rice by bacterial and Alternaria metabolites, nivalenol, kojic acid, STER, moniliformin, fusaric acid, fumonisin B3, citrinin, 3-nitropropionic acid, andrastin A, cytochalasins, emodin and physicon.

Mycotoxins frequently contaminate cereals and their fermented products, however, the carry–over profiles and concentrations of mycotoxins in the final product depend on the processing techniques employed. Therefore, the fate of mycotoxins in two popularly consumed Nigerian cereal-based beverages, kunu-zaki and pito, were studied using the raw cereals, their malted forms and the final drinks. Liquid chromatography tandem mass spectrometric analysis revealed 24 and 33 fungal metabolites in kunu-zaki and pito respectively, and their cereal inputs. Among the metabolites were 12 mycotoxins (alternariol, alternariolmethylether, beauvericin, deoxynivalenol, enniatin A and B, fumonisin B1 (FB1), FB2 and FB3, fusaproliferin, moniliformin and zearalenone). Mycotoxin levels were higher in the maize-based kunu-zaki (

Toxins of microbial origin frequently contaminate foodstuffs worldwide and pose a serious hazard to humans. This study reports on LCMS/MS quantification of multiple fungal and bacterial toxins, from household sampling of 50 traditionally prepared maize-fufu samples from Bamunka village, western highlands of Cameroon. Seventy-four metabolites including aflatoxin B1 (AFB1) (12/50: mean 0.9, range n.d-1.8 μg kg −1 ), cereulide (50/50: mean 37; range 1–236 μg kg −1 ), deoxynivalenol (DON) (50/50: mean 23, range 14–55 μg kg −1 ), fumonisin B1 (FB1) (50/50: mean: 151, range 48–709 μg kg −1 ), nivalenol (NIV) (50/50; mean 268, range 116–372 μg kg −1 ), patulin (PAT) (15/50:mean 105, range 12–890 μg kg −1 ) and zearalenone (ZEN) (50/50: mean 49, range 5–150) were detected; and of note every sample contained at least 27 toxic compounds. While individual toxin levels were mostly low there is always concern regarding mixtures, for which data are absent or limited. This study reports several novel observations of toxins not previously reported in maize, and the mixture of toxins, e.g. cereulide, PAT and ZEN derivatives (ZEN-cis and ZENsulfate-cis) are reported for the first time in Cameroonian food.

The microbiological safety of spontaneously fermented foods is not always guaranteed due to the undefined fermenting microbial consortium and processing materials. In this study, two commonly consumed traditional condiments (iru and ogiri) and their respective raw seeds (locust bean and melon) purchased from markets in south-western Nigeria were assessed for bacterial diversity and mycotoxin contamination using 16S rRNA gene sequencing and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively. Two hundred isolates obtained from the raw seeds and condiments clustered into 10 operational taxonomic units (OTUs) and spanned 3 phyla, 10 genera, 14 species and 2 sub-species. Bacillus (25%) and Staphylococcus (23.5%) dominated other genera. Potentially pathogenic species such as Alcaligenes faecalis, Bacillus anthracis, Proteus mirabilis and Staphylococcus sciuri subsp. sciuri occurred in the samples, suggesting poor hygienic practice during production and/or handling of the condiments. A total of 48 microbial metabolites including 7 mycotoxins [3-nitropropionic acid, aflatoxin B1 (AFB1), AFB2, beauvericin, citrinin, ochratoxin A and sterigmatocystin] were quantified in the food samples. Melon and ogiri had detectable aflatoxin levels whereas locust bean and iru did not; the overall mycotoxin levels in the food samples were low. There is a need to educate processors/vendors of these condiments on good hygienic and processing practices.

A pilot, cross-sectional, correlational study was conducted in eight rural communities in northern Nigeria to investigate mycotoxin exposures in 120 volunteers (19 children, 20 adolescents and 81 adults) using a modern LC–MS/MS based multi-biomarker approach. First morning urine samples were analyzed and urinary biomarker levels correlated with mycotoxin levels in foods consumed the day before urine collection. A total of eight analytes were detected in 61/120 (50.8%) of studied urine samples, with ochratoxin A, aflatoxin M1 and fumonisin B1 being the most frequently occurring biomarkers of exposure. These mycotoxin biomarkers were present in samples from all age categories, suggestive of chronic (lifetime) exposures. Rough estimates of mycotoxin intake suggested some exposures were higher than the tolerable daily intake. Overall, rural consumer populations from Nasarawa were more exposed to several mixtures of mycotoxins in their diets relative to those from Kaduna as shown by food and urine biomarker data. This study has shown that mycotoxin co-exposure may be a major public health challenge in rural Nigeria; this calls for urgent intervention. Keywords: Biomarker, Exposure assessment, Food safety, Human urine, Mycotoxin biomonitoring, Nigeria

Many individuals are not only food insecure but chronically exposed to high levels of mycotoxins through their diets in many developing countries. Seventy composite samples of stored maize grains were collected from farmers’ storage structures in five agro-ecological zones (AEZs) of Nigeria where maize is predominantly produced between August 2011 and February 2012. The grains were analysed for mycotoxin contamination with the liquid chromatography tandem mass spectrometry method and mycotoxin occurrence maps constructed from the database of the distribution of the toxins. A risk assessment was also carried out in order to provide information on the extent of human exposure to the toxins. Twelve regulated mycotoxins with negative economic and public health consequences were detected in the maize grains across the AEZs at concentrations exceeding the maximum allowable limits including AFM1 that was detected for the first time in Nigerian maize. There is a high risk of contamination of the stored grains by Nigerian consumers especially in the Derived and Southern Guinea Savannas, resulting in a national burden of between 126.85 and 38,682.29 DALYs. Intervention strategies are therefore needed across the AEZs to ensure that safe and wholesome foods are made available to the populace.

Seventy composite samples of maize grains stored in five agro-ecological zones (AEZs) of Nigeria where maize is predominantly produced were evaluated for the presence of microbial metabolites with the LC-MS/MS technique. The possible relationships between the storage structures and levels of mycotoxin contamination were also evaluated. Sixty-two fungal and four bacterial metabolites were extracted from the grains, 54 of which have not been documented for maize in Nigeria. Aflatoxin B1 and fumonisin B1 were quantified in 67.1 and 92.9 % of the grains, while 64.1 and 57.1 % exceeded the European Union Commission maximum acceptable limit (MAL) for aflatoxin B1 and fumonisins, respectively. The concentration of deoxynivalenol was, however, below the MAL with occurrence levels of 100 and 10 % for its masked metabolite, deoxynivalenol glucoside. The bacterial metabolites had low concentrations and were not a source of concern. The storage structures significantly correlated positively or negatively (p

In order to facilitate easy and rapid identification of aflatoxin-producing Aspergillus species, the phenotypic traits of Aspergillus section Flavi isolates were examined on neutral red desiccated coconut agar (NRDCA). Phenotype variations in colony morphology and the relationship between colour/intensity of fluorescence and aflatoxin production were assessed. The isolates included 10 Aspergillus minisclerotigenes strains, 11 non-aflatoxigenic Aspergillus flavus L strains, 29 aflatoxigenic A. flavus L strains and 20 strains each of Aspergillus parasiticus and Aspergillus parvisclerotigenus. The NRDCA medium supported morphological differentiation of the four species based on colony features, conidia type and colour. In particular, the two very closely related minisclerotial species, A. minisclerotigenes and A. parvisclerotigenus, were clearly differentiated by their colony colour on NRDCA. All toxigenic isolates produced aflatoxins in the culture medium in varying quantities. Plates of aflatoxigenic A. flavus L strains fluoresced bluish purple/lavender around the colony on the obverse and pastel blue on the reverse side due to aflatoxin B production while those of A. minisclerotigenes, A. parasiticus and A. parvisclerotigenus fluoresced with a light blue or light turquoise ring around the colony on the obverse and light sky blue or cadet blue on the reverse side depending on the amount of aflatoxin B and G produced. The colour of fluorescence significantly correlated (r=0.95, P=0.001) with the type(s) of aflatoxins produced by the isolates. In addition, the concentration of aflatoxins significantly (r=0.92; P=0.001) influenced the intensity of fluorescence in the aflatoxin-producing species. NRDCA can therefore be used for the rapid identification of Aspergillus section Flavi species based on colonial characteristics, and grouping of species into B and B+G aflatoxin producers within 5 days thus obviating the need for chemical analysis of the culture.

A survey in African snacks was carried out in order to evaluate the intake of 23 mycotoxins. The African snack samples were purchased from street vendors within Lagos metropolis (Nigeria) and evaluated for the presence of 23 mycotoxins using a modified QuEChERS procedure coupled with liquid chromatography-triple quadrupole linear ion trap mass spectrometer. The snacks included akara, baked coconut, coconut candy, donkwa, groundnut cake (kulikuli), lafun, milk curd (wara), fresh and dried tiger-nuts, and yam flour. Only three mycotoxins were detected in 23.8% of the studied snacks, and at concentrations ranging from 6 to 54 μg kg−1. The concentrations of aflatoxin B1 (AFB1) and AFB2 reached 23 μg kg−1 and 3 μg kg−1, respectively. Moreover a sample of baked coconut contained α-zearalenol (α-ZOL), which was up to 54 μg kg−1 in coconut candy. As considers prevalence, aflatoxins and α-ZOL were not detected in lafun and groundnut-based snacks (donkwa and kulikuli), whereas each of the three mycotoxins contaminated 12.5% (1/8) of the coconut-based samples. This is the first report of α-ZOL in cassava and coconut, and their products. AFB1 and total aflatoxins (TAFs) concentrations exceeded the maximum allowable limit recommended by National Agency for Food and Drug Administration and Control Nigeria (NAFDAC) in one sample of baked coconut (AFB1 = 23 μg kg−1 and TAFs = 26 μg kg−1) and donkwa (AFB1 = 19 μg kg−1 and TAFs = 21 μg kg−1).

This study sought to have an insight into the mechanism of action of diseases responsible for the susceptible Codiaeum variegatum (garden croton) leaves induced by Fusarium species and the clinical importance of the d isease resistant types. The plants were obtained fro m the Babcock University Germp lasm Repository. Therefore, phytopathogenic Fusarium species were isolated fro m three diseased susceptible cult ivars of C. variegatum (ovalifolium, royal-like and punctatum). Accordingly, lect in was isolated, purified and characterized fro m the leaves of a resistant garden croton cultivar (royal), and further evaluated for antifungal act ivity using isolates of Fusarium lateritium and F. semitectum obtained fro m the three diseased cultivars . The heamagglutinating activity of the purified lect in was non selective to type of blood group (A, B, A B and O) and was inhib ited by fructose, sialic acid, and copper sulphate, but was enhanced by galactose, calciu m chloride, sodium chloride and magnesium chloride. Optimu m heamagglutinating activ ity of the lectin was achieved at 30- 40℃ and pH 5.0-6.0. The lectin exh ibited antifungal activity against the two Fusarium species in a non-concentration dependent manner. It is therefore concluded that Fusarium species are major phytopathogens of the garden croton plant and their spectrum of pathogenicity is dependent on the presence or absence of lectins. In addition, the resistant cultivar of C. variegatum (cv. royal) used in this study may be a suitable candidate for the prevention and treatment of fungal infections.

Peanut cake samples were collected from major markets in five states of Nigeria and evaluated for incidence of toxigenic Aspergillus section Flavi populations, and aflatoxin B 1 (AFB 1 ) levels by liquid chromatography tandem mass spectrometry (LC–MS/MS). The awareness of consumers to the presence of aflatoxin in the snack and potential health risks of its regular ingestion was evaluated by questionnaire analysis. Aspergillus section Flavi populations were recovered from 83% of the peanut cake samples. Aspergillus flavus L-strain was the most predominant (>56%) across the states while Aspergillus tamarii had the least mean incidence (2.7%). The incidence of atoxigenic strains was significantly ( p p 1 in concentrations exceeding the NAFDAC recommended level for AFB 1 in food and reaching up to 2824 μg/kg. There was a weak positive correlation ( r = 0.32, p = 0.03) for the relationship between the incidence of toxigenic strains in the samples and AFB 1 concentration. The consumer awareness data showed that 64% of the respondents consumed peanut cake; majority of who are youth of economic and reproductive age. Eighty-five percent of the consumers lacked awareness of aflatoxin contamination in the snack and possible health risks associated with its ingestion.

The fungal and multi-mycotoxin profiles of groundnuts sold in domestic markets in Nigeria as well as the associated risk to consumers were assessed in the present study. Four hundred fungal isolates representing mainly Aspergillus [58.6%: Aspergillus section Flavi (37.1%) and A. niger- clade (21.5%)], Penicillium (40.9%) and Fusarium (0.5%) were isolated from 82 (97.6%, n = 84) groundnut samples collected from four agro-ecological zones (AEZs) of Nigeria. The incidence of aflatoxin-producing A. flavus isolates (71%) was significantly ( p 1 , AFB 2 , AFG 1 , AFG 2 and AFM 1 ), beauvericin (BEAU), cyclopiazonic acid (CPA), moniliformin, nivalenol and ochratoxin A] and four bacterial metabolites were detected in the groundnuts by liquid chromatography tandem mass spectrometry. Aflatoxins (39%; max: 2076 μg/kg; mean: 216 μg/kg) were detected in more samples than any other mycotoxin. About 25, 23 and 14% of the samples respectively were above the 2 μg/kg AFB 1 , 4 and 20 μg/kg total aflatoxin limits of the European Union and US FDA respectively. The mean margins of exposure of AFB 1 and total aflatoxins for adult consumers were 1665 and 908, respectively, while mean estimated daily intake values for infants, children and adults were

A preliminary survey involving limited sample size was conducted to determine the spectrum of moulds and mycotoxins in wheat grains from flour mills and local markets in Nigeria. Fourteen wheat samples were analyzed for moulds using standard mycological methods and for toxic fungal metabolites using a liquid chromatography-tandem mass spectrometric method. Fusarium (range of incidence 12.5–61.7%) dominated in the wheat grains though species of Aspergillus (range of incidence 2.24–3.86%) were also recovered from the samples. The identified fungal species were Aspergillus flavus (7.7%), Aspergillus niger clade (2.6%), Fusarium avenaceum (10.9%), Fusarium culmorum (22.4%) and Fusarium graminearum (56.4%). A total of 54 microbial metabolites were detected in the samples at concentration ranging between 0.01 μg/kg for macrosporin and 2560 μg/kg for deoxynivalenol. Among the four mycotoxins addressed by regulations in the European Union (EU) found in the samples, deoxynivalenol (incidence 100%) dominated in the samples and its levels exceeded the maximum acceptable EU limit (750 μg/kg) in 36% of the samples. This report underscores the need for more robust surveys with larger sample sizes and across several agro-ecologies in the country.

The spectrum of mycotoxins and other fungal metabolites was evaluated by a liquid chromatography/electrospray ionization-tandem mass spectrometric (LC/ESI-MS/MS) technique in 29 peanut cake samples collected from markets in five states of Nigeria. A total of 20 fungal metabolites were detected at concentrations up to 7400 μg/kg in case of kojic acid. Metabolites produced by Aspergillus species were the most prevalent toxins. As considers mycotoxins addressed by regulations, aflatoxins exceeded the USDA maximum limit of 20 μg/kg in about 90% samples. Seven fungal metabolites reported in this study have to our knowledge never been found previously to occur in naturally contaminated grains, nuts and oil seeds or their products. Possible health effects of the observed concentrations of fungal metabolites were discussed based on toxicological data from literature.

We investigated 16 fonio millet and 17 sesame samples by LC/ESI–MS/MS for the spectrum of microbial metabolites contaminating these seeds. Forty-eight fungal and four bacterial metabolites were detected in fonio, while 28 fungal and two bacterial metabolites were found in sesame. Altogether, 55 metabolites were identified in both grains, 18 of which are reported for the first time to naturally occur in cereals and oil seeds. The metabolite concentrations reached 7,280 μg/kg in fonio for aurofusarin and 64,600 μg/kg in sesame for kojic acid. Aflatoxin contaminated 81 % of fonio samples at concentrations less than the 4 μg/kg maximum allowable limit (MAL) set by European Union (EU). In contrast, aflatoxin was not detected in sesame. Zearalenone levels exceeded the EU MAL (75 μg/kg) in one sample of fonio (987 μg/kg). About 62.5 % (30 out of 48) of the metabolites without regulations occurred in more than 50 % of samples of one or both seeds, while 3-nitropropionic acid, beauvericin, brevianamid F, curvularin, emodin, equisetin, macrosporin A, monocerin and tenuazonic acid were the most prevalent, occurring in all samples of either fonio, sesame or both. This is the first study reporting mycotoxin contamination in sesame in Nigeria and the broad range of microbial metabolites in millet and sesame.