Mycotoxin Research最新文献

Mycotoxins such as aflatoxins (AFs), fumonisins (FBs), zearalenone (ZEN), and deoxynivalenol (DON) pose a risk to public health due to their carcinogenic potency (AFs and FBs) and anti-nutritional effects. The hazards associated with mycotoxins are accentuated where food management practices, control, and regulatory systems from farm to plate are sub-optimal. Information on the frequency of these mycotoxins in rice commercialized in markets in sub-Sahara Africa (SSA) is limited. The current study examined AF concentrations in 527 rice samples collected from 54 markets in five SSA countries. Grain quality characteristics, processing methods, and origin of samples were contrasted with toxin levels. In total, 72% of the samples had detectable AFs levels (range = 3.0 to 89.8 µg/kg). Forty-seven percent (47%) of the samples had AFs above 4 µg/kg, the European Union maximum level (ML), and were evaluated for cooccurrence with FBs, ZEN, and DON. Total AFs and ZEN cooccurred in 40% of the samples, and 30% of the positive ZEN samples had concentrations above the ML of 75 µg/kg. Total AFs did not co-occur with FBs and DON. Multivariate analysis revealed that length-to-width ratio (p < 0.0001), mixed variety for width (p = 0.04), and chalkiness (p = 0.009) significantly influenced aflatoxin concentrations. Slender grains had higher AFs concentrations than bold and medium grains (p < 0.0001). Possible strategies to mitigate mycotoxin contamination in rice include improving grain quality traits and practicing proper drying and hermetic storage before and after milling. These findings provide valuable insights for both domestic and international actors in establishing and strengthening regulations and management systems to mitigate rice mycotoxin contamination.

Aflatoxins are toxic secondary metabolites produced by Aspergillus species that infect staple foods like maize causing threat to public health and economic impacts. The use of atoxigenic Aspergillus species is considered one of the promising technologies to prevent aflatoxin contamination in maize. Tanzania approved the use of aflatoxin biocontrol (Aflasafe®) in 2018 and introduced it to eight districts. Adoption and effectiveness of this technology depend on many factors including application of pre- and post-harvest practices. There is scant information on awareness of biocontrol and factors which influence the adoption and effectiveness of this technology. A cross-sectional study was conducted in Tanzania to assess awareness and identify factors influencing adoption of the technology. Data was collected from 334 smallholder farmers in Kiteto and Chemba districts and analyzed using SPSS version 20; p-values < 0.05 using a two-tailed test were considered statistically significant. Results indicated 95.4% are not aware and that only 2.7% of the farmers had used biocontrol technology. The use of biocontrol was significantly associated with high income level (p = 0.001) and exposure to print media (p = 0.03) and radio (p = 0.008). The use of hybrid seed (p = 0.01), grazing (p = 0.017), and rotation of crops on yearly basis (p = 0.024) were also significantly associated with the use of biocontrol. Income limits the use of biocontrol, requiring government subsidies for Aflasafe and a premium market for aflatoxin-free maize. Aflatoxin awareness and sensitization on adherence to good pre-harvest practices should be emphasized to enhance adoption of the technology.

Molds of the genus Fusarium infect nearly all types of grain, causing significant yield and quality losses. Many species of this genus produce mycotoxins, which pose significant risks to human and animal health. In beer production, the complex interaction between primary fungal metabolites and secondarily modified mycotoxins in barley, malt, and beer complicates the situation, highlighting the need for effective analytical methods to quickly and accurately monitor these toxins. We developed and validated a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to simultaneously analyze 14 Fusarium toxins, including modified forms (deoxynivalenol (DON), DON-3-glucoside, 3-acetyl-DON, 15-acetyl-DON, nivalenol, fusarenone X, HT-2 toxin, T-2 toxin, the enniatins A, A1, B, B1, beauvericin, and zearalenone) in barley and throughout the malting process. Stable isotope dilution assays (SIDAs) and matrix-matched calibration were used for quantification. A micro-malting setup was established to produce Fusarium-contaminated barley malt under reproducible conditions using targeted inoculation with F. culmorum. Mycotoxins were quantified throughout the malting process and compared to the content of fungal DNA. Further, the impact of various malting parameters was investigated, thus revealing that different malting scenarios exhibited different toxin enrichment patterns. We demonstrated that mycotoxin concentration and the ratio of DON to DON-3-glucoside changed throughout the malting processes, depending on fungal spore concentrations, germination temperature, and malting temperature. The study highlights the complexity of mycotoxin dynamics in malt production and the importance of optimized processing conditions to minimize toxin levels in final malt products.

The infant flours produced in Burkina Faso are essentially a mixture of cereals and legumes. These raw materials are frequently contaminated with mycotoxins which pose a huge food safety and public health threat. The objective of this study was to determine mycotoxin levels in raw materials and infant flours in Ouagadougou and to investigate the impact of decontamination on the raw materials used in infant flour production. A total of 22 cereals and 17 legumes as raw materials and 26 infant flour samples were analysed for aflatoxins, fumonisin B₁ (FB₁), and ochratoxin A (OTA) by liquid chromatography coupled to tandem mass spectrometry, while saline treatment and hand-sorting of grains in mycotoxin reduction were tested. All the samples of raw materials and infant flours were contaminated with aflatoxins, whereas 20.5% and 38.5% of raw materials and 57.7% and 61.5% of infant flours, respectively, were contaminated by FB₁ and OTA. These decontamination assays significantly reduced the levels of mycotoxins. AFB₁ was reduced by 48% after soaking of maize for 6 h in a 6% NaCl solution. Sorting resulted in a 92% reduction in AFB₁ content in peanut. However, soaking in saline solution did not reduce the FB₁ and OTA contents. Sorting did not also reduce FB₁ contents in peanut. Sorting and soaking in 6% saline solution for 6 h are production processes that lead to a reduction in the level of contamination by aflatoxins in maize and peanut used as raw materials for infant flour production.

The silymarin complex extracted from milk thistle provides significant health benefits, particularly due to its antioxidant and hepatoprotective properties. However, plant substances can be contaminated by a number of fungi types and their secondary metabolites-mycotoxins. This work deals with the determination of aflatoxins and zearalenone and its metabolites in 39 different samples grown in 2020 and 2021. Analysis of mycotoxins was performed by UHPLC-MS/MS after immunoaffinity column AFLAPREP^® and EASI-EXTRACT^® ZEARALENONE clean-up. The presence of aflatoxins was not confirmed in the monitored samples, but 1/3 of the samples were contaminated with zearalenone in the range of 2.8-378.9 µg/kg. Metabolites of zearalenone such as α-zearalenol, α-zearalanol, and β-zearalanol were not detected in any of the samples. β-Zearalenol was found in two samples (2.6 µg/kg and 29.8 µg/kg).

Exposure of school children to aflatoxin and fumonisin is mainly through diet. In Kenyan public schools, children are given porridge made from maize flour for breakfast, a mixture of maize and beans, also known as githeri for lunch and ugali for dinner. Nixtamalization has proved to reduce mycotoxins in most cereals and not a mixture of maize and beans. This study, therefore, aimed to assess the exposure of primary school children in Turkana County to aflatoxin and fumonisin through maize-based food under the school meals program and the effectiveness of nixtamalization in the reduction of these mycotoxins. Samples of githeri were randomly collected from all public primary schools (n = 128) under the homegrown school meals program in Turkana County and analyzed for aflatoxin and fumonisin. The data was analyzed using SAS software, version 9.4. The deterministic model was used to calculate the estimated daily intake (EDI) and the margin of exposure (MOE) used to characterize the exposure risk. The contaminated samples were then treated with various concentrations of Ca(OH)₂, 0.5-2.5%. The treated samples were cooked for 60 and 75 min and soaked for 6 and 8 h. Forty percent of the schools contained githeri samples with aflatoxin B1 levels above 5 µg/Kg, the maximum limit for Kenya. Exposure to aflatoxin B1 and total aflatoxin was up to 2 µg/kg/bw/day. The range for fumonisin exposure was 60-80 µg/kg/bw/day. Ca(OH)₂ concentration levels of up to 2.5% reduced aflatoxin by 75% and fumonisin by 72%. The findings indicate that githeri is contaminated with aflatoxin and fumonisin which exposes school children to these mycotoxins and nixtamalization can be used to reduce mycotoxin contamination in githeri.

To assess the efficacy of Toxfin and Novasil as aflatoxin-binding agents in broilers exposed to aflatoxin B₁ (AFB₁) from 11 to 30 days, 288 mixed-sex Ross 308 broiler chickens were randomly allocated to four dietary groups: control feed, control feed + 0.25 mg/kg AFB₁, AFB₁ feed + 0.3% Toxfin, and AFB₁ feed + 0.3% Novasil. The evaluation encompassed growth performance for the grower (11-20 days), finisher (21-30 days), and overall (11-30 days) phases, carcass characteristics, serum biochemical components, liver function enzymes, hepatic antioxidant capacity, AFB₁ residue in the liver and kidney, and ileal morphology at 30 days, and apparent nutrient digestibility during 29-30 days. Exposure to AFB₁ significantly resulted in reduced growth efficiency, lowered carcass yields, liver hypertrophy, impaired metabolic and hepatic functions, liver oxidative stress, disrupted ileum architecture, diminished nutrient digestibility, and accumulated AFB₁ in the liver and kidney. Conversely, supplementation of Toxfin or Novasil significantly augmented body weight gain (BWG) and reduced feed conversion ratio (FCR) during the finisher and overall phases, elevated BWG in the grower phase, heightened levels of glucose, hepatic protein, and glutathione peroxidase, declined malondialdehyde content, improved apparent metabolizable energy, and lowered AFB₁ residues in the liver and kidney. Furthermore, Toxfin inclusion significantly reduced FCR during the grower phase, enhanced European production efficiency factor during the grower and overall phases, augmented dressing percentage, declined proportional liver weight, elevated concentrations of total protein, albumin, and total antioxidant capacity, heightened villus surface area, and boosted crude protein digestibility. To conclude, incorporating 0.3% Toxfin into broilers' feeds confers a more effectual safeguard than Novasil against the deleterious consequences of AFB₁ exposure.

Aflatoxin B1 (AFB1) is a fungal toxin consistently found as a contaminant in food products such as cereals, nuts, spices, and oilseeds. AFB1 exposure can lead to hepatotoxicity, cancer, immune suppression, reproductive deficiency, nutritional dysfunction, and growth impairment. AFB1 has also been listed as one of the most potent human carcinogens by the International Agency for Research on Cancer. Although the correlation between AFB1 exposure and cancer initiation and progression is already reported in the literature, very little information is available about what molecular pathways are affected during cancer development. Considering this, we first selected AFB1-responsive genes involved in five deadliest cancer types including lung, colorectal, liver, stomach, and breast cancers from the Comparative Toxicogenomics Database (CTD). Then, using the PANTHER database, a statistical overrepresentation test was performed to identify the significantly affected pathways in each cancer type. The gonadotropin-releasing hormone receptor (GnRHR) pathway, the CCKR signaling pathway, and angiogenesis were found to be the most affected pathways in lung, breast, liver, and stomach cancers. In addition, AFB1 toxicity majorly impacted apoptosis and Wnt signaling pathways in liver and stomach cancers, respectively. Moreover, the most affected pathways in colorectal cancer were the Wnt, CCKR, and GnRHR pathways. Furthermore, gene analysis was also performed for the most affected pathways associated with each cancer and identified thirteen key genes (e.g., FOS, AKT1) that may serve as biological markers for a particular type of AFB1-induced cancer as well as for in vitro AFB1 toxicological studies using specific cancer cell lines.

The debranning process, at an industrial scale, was applied to grains of two wheat cultivars to determine its effect on Fusarium mycotoxin content and antioxidant activity. Grain samples from the BRS Marcante and BRS Reponte wheat cultivars, naturally contaminated by Fusarium, were used in the study. The dry wheat samples were processed on the polisher once or twice and evaluated by hardness index, chemical composition (moisture, protein, and ash), deoxynivalenol (DON) and zearalenone (ZON) levels, phenolic content, and antioxidant activity. In the BRS Marcante cultivar, the debranning process only slightly reduced the DON and ZON contents in whole-wheat flours compared with the previous cleaning treatment (no-debranned). In the BRS Reponte cultivar, the DON concentration decreased by 36% at a debranning ratio of 5%, obtained by polishing, compared with prior cleaning treatment (no-debranned). In addition, the polishing reduced the ZON level by 56% compared with the cleaned wheat. The debranning process did not reduce the antioxidant capacity. Therefore, debranning is a suitable technology to obtain safer and healthier food by minimizing the mycotoxin content and retaining antioxidant capacity.

Mycotoxins, such as aflatoxin B₁ (AFB₁), deoxynivalenol (DON), fumonisins (FBs), ochratoxin A (OTA), T-2 toxin (T-2), and zearalenone (ZEN), can contaminate animal feeds and pose risks to animal health and production performance. These mycotoxins are commonly found in cereals and grains, with the increased use of cereals in pet food, there is a rising concern about mycotoxin contamination among pet owners. To address this, we analyzed imported brands of feline and canine food from the Chinese market produced in 2021-2022. Ninety-three samples were analyzed, comprising 45 feline food and 48 canine food samples. Among them, 14 were canned food and 79 were dry food. The results indicate that AFB₁, DON, FBs, OTA, T-2, and ZEN occurred in 32.26%, 98.92%, 22.58%, 73.12%, 55.91%, and 7.53% of the samples, respectively. The most prevalent mycotoxin was DON, followed by OTA, T-2, AFB_1, and FBs, whereas ZEN was less frequently detected. The mean concentrations of the six mycotoxins in pet feed samples were 3.17 μg/kg for AFB₁, 0.65 mg/kg for DON, 2.15 mg/kg for FBs, 6.27 μg/kg for OTA, 20.00 μg/kg for T-2, and 30.00 μg/kg for ZEN. The levels of mycotoxins were generally below the limits of the Pet Feed Hygiene Regulations of China and the EU. Notably, a substantial majority of the pet food samples (88 out of 93) were contaminated by two or more mycotoxins. AFB₁, FBs, OTA, and ZEN occurred slightly more often in feline food than in canine food. Except for OTA, the contamination rates for the other five mycotoxins in canned food were lower than those in dry food. Moreover, except for AFB₁, the levels of the other five mycotoxins in canned foods were lower than those in dry foods. This study highlights the widespread contamination of pet foods with mycotoxins, which poses a significant risk to pets from continuous exposure to multiple mycotoxins.