Occurrence of Aflatoxins in Rice Intended for Infant Flour Production in Ouagadougou, Burkina Faso

A total of four samples of rice intended for infant flour production in Ouagadougou were received at the Physico-chemistry laboratory of Food Technology Department (DTA) for quality control. The latter were also tested for Aspergillus section Flavi presence and analyzed for aflatoxins B1, B2, G1 and G2 content using high performance liquid chromatography (HPLC). Among the twenty (20) strains of mold isolated from these samples, three Aspergillus section Flavi were obtained and cultivated in “Aspergillus flavus and parasiticus Agar (AFPA)” to ascertain if they belong to Aspergillus flavus or Aspergillus parasiticus species. The qualitative ability of aflatoxin production was also performed by fluorescence emission under ultra violet light at 365 nm after four days of incubation at 30 °C on Coconut Agar Medium (CAM). Statistical analysis results showed that 75% of samples were contaminated with total aflatoxins (AFs) with contents ranging from 0.54 ± 0.06 to 2.40 ± 0.07 µg/Kg. Aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) were detected in two contaminated samples. AFB1 had the highest concentration as compared with other aflatoxins. A significant level of contamination (p< 0.0001) was observed in sample R441 compared to other sample types.

Aflatoxins: Food Safety, Human Health Hazards and Their Prevention

Aflatoxins (AFTs) are group of secondary metabolites produced by filamentous fungi such as Aspergillus flavus, A. parasiticus, A. nomius, and Emericella nidulans. AFTs contaminate foods, feeds, other raw ingredients used to produce them and that pose a significant threat to human health. These toxins designated as aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), and aflatoxin G2 (AFG2), aflatoxin M1 (AFM1) and aflatoxin M2 (AFM2) are hydroxylated metabolites form of AFB1 and AFB2 are known as difuranocoumarin compounds. Naturally, these AFs have carcinogenic, teratogenic and mutagenic effects and caused several metabolic disorders such as aflatoxicosis in domestic animals and humans worldwide. For the increasing in cancer incidences these risk factors are liable. AFB1 is 1000 times more potent hepatocarcinogen found in food then benzo (α) pyrene carcinogen. This chapter offers contamination sources, effects and their controlling approaches to confirm the food safety.

Occurrence of mycotoxins in selected agricultural and commercial products available in eastern Poland

The objective of this study was the estimation of the content of 13 mycotoxins (diacetoxyscirpenol, T-2 toxin, HT-2 toxin, nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, fusarenone X, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, ochratoxin A, and zearalenone) in various products from the eastern part of Poland. The content of mycotoxins in the analysed samples was assayed using the extraction method combined with HPLC-MS/MS analysis. We found mycotoxins in 25 of the 92 samples tested (27%). Contamination with mycotoxins was noted most frequently in samples of cereals – 56% – and also in samples of flour and cocoa, in which a content of mycotoxins was noted in 24 and 16% of the samples, respectively. The most frequently identified were the following – deoxynivalenol detected in 18 samples (72%), zearalenone detected in eight samples (32%), toxin HT-2 detected in four samples (16%), ochratoxin A identified in three samples (12%), and toxin T-2 detected in one sample (4%). In one analysed sample of mixed flour and in one analysed sample of wheat and rye flour, the maximum allowable concentration was exceeded in the case of two identified mycotoxins – deoxynivalenol (2,250 μg/kg) and ochratoxin A (15.6 and 17.1 μg/kg).

Aflatoxins and Moisture Levels in Edible Oils Produced in Burkina Faso

Aim: The study aim was to assess aflatoxin and moisture levels in edible oils produced and consumed in Burkina Faso to know the impact on consumer health. Methodology: A total of 61 samples of refined cottonseeds oils and crude peanut oils were collected from Ouagadougou, Bobo Dioulasso and surrounding areas. Aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2) were determined by HPLC and moisture by differential weighing after oven drying. Results: The moisture content of peanut oils were ranged from 0.06 to 0.18% and cottonseeds oils from 0.02 to 0.17%. The moisture average is 0.13% for peanut oils and 0.08% for cottonseeds oils (P<0.05). The moisture of all oils is lower and conform to the Codex Alimentarius standard. AFB1, AFB2, AFG1 and AFG2 were identified in 86.89% of the oil samples analyzed. The proportion of samples contaminated with AFB1 is 57.38%, 59.02% for AFB2, 42.62% for AFG1 and 65.57% for AFG2. The AFB1 average of peanut oils is 6.21 ng/g while that of cottonseeds oils is 0.03 ng/g. The AFB2 average of peanut oils is 0.89 ng/g against 0.04 ng/g for cottonseeds oils (P<0.05). The AFG1 average of peanut oils is 0.54 ng/g and 0.08 ng/g for cottonseeds oils (P<0.05). The AFG2 average of peanut oils was 0.66 ng/g against 0.64 ng/g for cottonseeds oils. AFG2 had the highest proportion of all oils while AFB1 has the highest concentration and proportion in peanut oils. The 72.13% samples analyzed in this study comply with the European Community standard for aflatoxin B1 level maximum in oilseeds. Conclusion: Aside from the moisture content that comply with the standard, aflatoxins are present at varying levels and can negatively impact the consumer health. It is important to strengthen the monitoring and production system in order to have quality oil.

Effect of Drying Temperatures and Exposure Times on Aspergillus flavus Growth and Aflatoxin Production on Artificially Inoculated Hazelnuts

ABSTRACT Aspergillus flavus may colonize hazelnuts and produce aflatoxins in the field and during storage. The main purpose of this study was to investigate the influence of drying temperature and exposure times on the viability of A. flavus and its ability to produce aflatoxins during the drying process and storage. Hazelnuts were inoculated with A. flavus and dried at different temperatures to reach 6% moisture content and a water activity (aw) of 0.71, a commercial requirement to avoid fungal development and aflatoxin contamination. Hazelnuts were dried at 30, 35, 40, 45, and 50°C and subsequently stored at 25°C for 14 days. After drying at 30, 35, and 40°C, increased amounts of A. flavus were evident, with the highest concentration occurring after drying at 35°C ([6.1 ± 2.4] × 106A. flavus CFU/g). At these temperatures, aflatoxins were detected only at 30 and 35°C. Aflatoxins, however, were present at higher levels after drying at 30°C, with concentrations of 1.93 ± 0.77 μg/g for aflatoxin B1 (AFB1) and 0.11 ± 0.04 μg/g for aflatoxin B2 (AFB2). After 14 days of storage, the highest A. flavus concentration and the highest levels of mycotoxins were detected in samples treated at 35°C ([8.2 ± 2.1] × 107A. flavus CFU/g and 9.30 ± 1.58 μg/g and 0.89 ± 0.08 μg/g for AFB1 and AFB2, respectively). In hazelnuts dried at 45 or 50°C, no aflatoxins were found either after drying or storage, and a reduction of A. flavus viable conidia was observed, suggesting that a shorter and warmer drying is essential to guarantee nut safety. The lowest temperature that guarantees the lack of aflatoxins should be selected to maintain the organoleptic quality of hazelnuts. Therefore, 45°C should be the recommended drying temperature to limit A. flavus growth and aflatoxin contamination on hazelnuts. HIGHLIGHTS

Identification of Two Novel Peanut Genotypes Resistant to Aflatoxin Production and Their SNP Markers Associated with Resistance

Aflatoxin B1 (AFB1) and aflatoxin B2 (AFB2) are the most common aflatoxins produced by Aspergillus flavus in peanuts, with high carcinogenicity and teratogenicity. Identification of DNA markers associated with resistance to aflatoxin production is likely to offer breeders efficient tools to develop resistant cultivars through molecular breeding. In this study, seeds of 99 accessions of a Chinese peanut mini-mini core collection were investigated for their reaction to aflatoxin production by a laboratory kernel inoculation assay. Two resistant accessions (Zh.h0551 and Zh.h2150) were identified, with their aflatoxin content being 8.11%–18.90% of the susceptible control. The 99 peanut accessions were also genotyped by restriction site-associated DNA sequencing (RAD-Seq) for a genome-wide association study (GWAS). A total of 60 SNP (single nucleotide polymorphism) markers associated with aflatoxin production were detected, and they explained 16.87%–31.70% of phenotypic variation (PVE), with SNP02686 and SNP19994 possessing 31.70% and 28.91% PVE, respectively. Aflatoxin contents of accessions with “AG” (existed in Zh.h0551 and Zh.h2150) and “GG” genotypes of either SNP19994 or SNP02686 were significantly lower than that of “AA” genotypes in the mean value of a three-year assay. The resistant accessions and molecular markers identified in this study are likely to be helpful for deployment in aflatoxin resistance breeding in peanuts.