High Levels Of Aflatoxin B1 Research Articles

Safe and effective degradation of aflatoxins by food-grade culture broth of Aspergillus oryzae.

Aflatoxins (AFs) are carcinogenic fungal toxins contaminating up to 25% of the global food supply. Over half of the world's population is exposed to unmonitored levels of AFs, mostly aflatoxin B1 (AFB1). Despite numerous efforts over the past 60 years, there are no solutions to remove AFs safely from food. Here, we present a safe and effective AF-degrading product called "D-Tox", a filtered culture broth of Aspergillus oryzae grown in a food-grade liquid medium. When 5 ppm of AFB1 is added to D-Tox, ∼90% is degraded at 48 and 24 hr at room temperature and 50°C, respectively. Moreover, when varying amounts (0.1 ppm ∼ 100 ppm) of AFB1 are added to D-Tox at 100°C, over 95% of AFB1 is degraded in 1 hr, suggesting a nonenzymatic process. Examining degradation of 100 ppm AFB1 reveals that aflatoxin D1 (AFD1) is the major transient degradant of AFB1, indicating that degradation occurs irreversibly by lactone ring hydrolysis followed by decarboxylation. D-Tox further degrades AFD1 to unknown fragmented products. Importantly, the practical application of D-Tox is also demonstrated, as more than 70% of AFB1 is degraded when wheat, corn, and peanuts naturally contaminated with high levels of AFB1 (0.3 ∼ 4.5 ppm) are boiled in D-Tox for 1 hr. Additionally, D-Tox can degrade other lactone-ring containing mycotoxins, including patulin and ochratoxin. D-Tox exhibits no cytotoxicity under the conditions tested in MCF-7 breast cancer cell lines. In summary, D-Tox is a safe and effective AF-detoxifying product that can enhance global food safety.

Seasonal and Geographical Impact on the Mycotoxigenicity of Aspergillus and Fusarium Species Isolated from Smallholder Dairy Cattle Feeds and Feedstuffs in Free State and Limpopo Provinces of South Africa.

This study evaluated the impact of seasonal and geographical variations on the toxigenicity of Aspergillus and Fusarium strains previously isolated from smallholder dairy cattle feeds and feedstuffs sampled during summer and winter in the Free State and Limpopo provinces of South Africa (SA). In total, 112 potential toxigenic fungal species were obtained and determined for their capability to produce mycotoxins on solid Czapek Yeast Extract Agar (CYA); followed by liquid chromatography-mass spectrometry (LC-MS/MS) analysis. Our result revealed that 41.96% of the fungal species produced their respective mycotoxins, including aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), and zearalenone (ZEN), with higher levels of AFB1 (0.22 to 1045.80 µg/kg) and AFB2 (0.11 to 3.44 µg/kg) produced by fungal species isolated from summer samples than those in winter [(0.69 to 14.44 µg/kg) and (0.21 to 2.26 µg/kg), respectively]. The same pattern was also observed for AFB1 and AFB2 in Limpopo (0.43 to 1045.80 µg/kg and 0.13 to 3.44 µg/kg) and Free State (0.22 to 576.14 µg/kg and 0.11 to 2.82 µg/kg), respectively. More so, ZEN concentrations in summer (7.75 to 97.18 µg/kg) were higher than in winter (5.20 to 15.90 µg/kg). A similar observation was also noted for ZEN in Limpopo (7.80 to 97.18 µg/kg) and Free State (5.20 to 15.90 µg/kg). These findings were confirmed via Welch and Brown-Forsythe tests with significantly (p ≤ 0.05) higher mycotoxin levels produced by fungal strains obtained in samples during summer than those in winter. In contrast, the concentrations of mycotoxins produced by the fungal species from both provinces were not significantly (p > 0.05) different.

Occurrence of Aflatoxin B1 in Fresh and Boiled Liver Broiler Chickens in Zaria, Nigeria

There is an increasing concern for the contamination of poultry products with Aspergillus strains, responsible for the aflatoxin production. Therefore, the persistence of aflatoxin B1 was analyzed in 60 fresh liver divided into two-part one remains fresh and the other part boiled from live bird markets in Zaria, Nigeria, using indirect competitive enzyme link immunosorbent Assay (iELISA). A total of 66.7% of fresh liver and 16.7% of boiled liver were found to be contaminated with aflatoxin B1 above maximum detection limits. The levels of aflatoxin B1 contamination varied in decreasing order as follows: Sabon Gari, Zaria city, Dan Magaji and Tudun wada had aflatoxin level of 66.40 µg/kg, 41.45 µg/kg, 35.25 µg/kg and 29.80 µg/kg, respectively in fresh liver samples. The highest level of aflatoxin B1 in boiled liver was 29.02 µg/kg in Sabon Gari. The persistence of boiling aflatoxin B1 was significant (P < 0.05) in the liver of broilers. The occurrence of aflatoxin B1 in the liver of slaughtered broilers is dangerous and may adversely affect human health. It was concluded that the high level of AFB1 in birds sold in live-bird markets, meant for slaughter for human consumption may have adverse effects on human health. Strict measures should be adopted to monitor and regulate aflatoxin level in feeds and, subsequently, in edible tissues. Keywords: AFB1, ELISA, Chickens and Liver.

Evaluation of Aflatoxin B1 in poultry feeds marketed in Nsukka agricultural zone, Enugu State, South Eastern Nigeria

Aflatoxin contamination of poultry feeds is a major challenge to profitable poultry productivity and trade. This study was carried out to evaluate the levels of aflatoxin B1 (AFB1) contamination of poultry feeds commonly sold in Nsukka, Enugu State, Nigeria. A total of 48 representative feed samples, comprising 24 toll-milled and 24 commercial feeds, were collected. aflatoxin B1 was detected in all (100%) the samples analysed using Indirect Competitive ELISA technique at various concentrations, with AFB1 concentrations of toll-milled and commercial feeds samples ranging from 2.5 – 473.8 ppb and 1.1 – 1683.2 ppb, respectively. The mean AFB1 concentration (77.69 ± 19.36 ppb) of toll-milled feed samples was significantly less (p ≤ 0.05) than the mean AFB1 concentration of commercial feeds brands (231.10 ± 71.1 ppb). The mean AFB1 concentration of commercial brand A feeds (12. 11 ± 3.25 ppb) was significantly less (p < 0.05) than the mean concentrations of commercial brand B feeds (385.91 ± 152 ppb) and brand C feeds (425.90 ± 97.93 ppb). The toll-milled and commercial feeds samples evaluated showed that 79.17% and 70.8% of the feeds, respectively, had AFB1 concentrations above the United State Food and Drugs Administration action value, 20 ppb. The levels of AFB1 contaminations in the feed samples studied were high, and thus make the feeds unsafe for poultry consumption. Therefore, there is need for routine screening and monitoring of AFB1 in poultry feeds marketed in this area to avoid high levels of AFB1 in feeds and the subsequent accumulation in the poultry products.

Occurrence of Aflatoxins in Edible Vegetable Seeds and Oil Samples Available in Pakistani Retail Markets and Estimation of Dietary Intake in Consumers.

Aflatoxins (AFs) are secondary metabolites toxic to humans as well as animals. The environmental conditions, conventional agricultural practices, and illiteracy are the main factors which favor the production of AFs in food and feed. In the current study 744 samples of vegetable seeds and oils (soybean, sunflower, canola, olive, corn, and mustard) were collected and tested for the presence of aflatoxin B1 (AFB1) and total AFs. Liquid-liquid extraction was employed for the extraction of AFs from seeds and oil samples. Reverse phase high performance liquid chromatography equipped with fluorescence detection was used for the analysis. The results have shown that 92 (56.7%) samples of imported and 108 (57.0%) samples of local edible seeds were observed to be contaminated with AFs. All samples of edible seeds have AFB1 levels greater than the proposed limit set by the European Union (EU, 2 µg/kg) and 12 (7.40%) samples of imported seeds and 14 (7.40%) samples of local seeds were found in the range ≥ 50 µg/kg. About 78 (43.3%) samples of imported edible oil and 103 (48.3%) sample of local edible oil were observed to be positive for AFs. Furthermore, 16 (8.88%) and six (3.33%) samples of imported vegetable oil have levels of total AFs in a range (21–50 µg/kg) and greater than 50 µg/kg, respectively. The findings indicate significant differences in AFs levels between imported and local vegetable oil samples (t = 22.27 and p = 0.009) at α = 0.05 and a significant difference in AFs levels were found between vegetable seeds and oil samples (t = −17.75, p = 0.009) at α = 0.05. The highest dietary intake was found for a local sunflower oil sample (0.90 µg/kg/day) in female individuals (16–22 age group). The results have shown considerably high levels of AFB1 and total AFs in seeds and oil samples and emphasise the need to monitor carefully the levels of these toxic substances in food and feed on regular basis.

Determination of Aflatoxin B1 Contamination in Wheat and Rice Flour Collected from Iranian Market Using Simple and Reliable HPLC Method

Aflatoxin B1 (AFB1), as the most toxic mycotoxin, has a large variety of toxic effects to human and animals. To evaluate incidence of AFB1 in wheat flour and rice flour sold in Iranian markets, 40 samples including 16 wheat flour samples and 24 rice flour samples were collected from commercial brands commonly marketed in Iran and analyzed for their AFB1 content using post-column photochemical derivatization and HPLC. The mobile phase consisting of water, methanol and acetonitrile mixture (53:28:19, v/v/v). The sample preparation was done with simple extraction with acetonitrile and water (80/20, v/v) accompany with immunoaffinity column cleanup. Our results indicated a good recovery (minimal 90% in wheat flour and 97 % in rice flour) in spike range 0.2-8 µg.kg-1 with RSDs lower than 5%. The results showed both high incidence and high levels of AFB1 in rice flour samples compared to wheat flour. AFB1 was detected in 18.5% with maximum level of 0.26 µg.kg-1. AFB1 was found in 100% of rice samples with a mean and maximum level of 4.09±2.565 µg.kg-1 and 10.16 µg.kg-1, respectively. The results indicate that although the level of AFB1 in wheat flour is not comparatively critical point regarding quality of wheat flour, high incidence and high contamination level of AFB1 in rice flour samples could make serious health problems for Iranian consumers.

Effect of storage temperature on fungal growth and aflatoxin formation in oils extracted from wild almond nuts

The current research was performed to assess the fungal contamination in oils extracted from wild almonds (Alok) during 60 days of storage. To assess the influence of storage temperature on fungal growth and aflatoxin production, three batches of wild almond nuts were kept at 25, 30, and 35°C for 60 days, and extracted oils from nuts were evaluated at six periods of intervals. Storage at 25°C enhanced the fungal growth more rapidly while compared with the other temperatures, mainly due to offering the optimum temperature for the fungal proliferation. The highest level of aflatoxin B1 was noted at storage at temperature 30°C despite lower fungal growth at this temperature while compared with 25°C, which can be correlated with the optimum temperature for aflatoxin B1 production by Aspergillus species. Therefore, the association between fungi and aflatoxin production was not linear, while various environmental parameters affect this correlation. Practical applications Food products contaminated by fungi may be the source of aflatoxins at various stages like harvest, storage, extraction, and process, which can cause some health issues besides enormous economic losses. In this regard, the main postharvest issue correlated with wild almond is fungal growth on the kernels of grain through storage, which can result in an additional reduction in the quality of extracted oil including nutrients and unacceptability by consumers.

Occurrence and bioacessibility of mycotoxins in fish feed

ABSTRACT In this study Aflatoxin B1 (AFB1), ochratoxin A (OTA) and zearalenone (ZEN) occurrence in fish feed, regarding its chemical composition, were investigated. Besides, AFB1 bioaccessibility to fish was evaluated by in vitro digestion. Mycotoxins were extracted by QuEChERS and quantified by HPLC-FLD. Results showed that 93.3% of the samples were contaminated at maximum levels of 16.5, 31.6, and 322 µg/kg in the cases of AFB1, OTA, and ZEN, respectively. A positive correlation between OTA, ZEN contamination, and lipid content was observed. Risk estimation of feed consumption by fish at the highest levels of AFB1, OTA, and ZEN shows that the younger the fish, the higher the risk of exposure to mycotoxins. The AFB1 bioaccessibility assay showed that 85% of this mycotoxin may be absorbed by fish. Therefore, establishing maximum levels in the fishing sector is fundamental to contribute to feed quality and nutritional safety of fish species.

Aflatoxin B1 exposure and liver cirrhosis in Guatemala: a case–control study

ObjectiveIn Guatemala, cirrhosis is among the 10 leading causes of death, and mortality rates have increased lately. The reasons for this heavy burden of disease are not clear as the...

Abstract SY27-01: The changing etiology of liver cancer

Abstract Collectively liver cancer accounts for nearly 9% of all reported cancer deaths and is one of the most common causes of cancer mortality worldwide http://gco.iarc.fr/ (1). The incidence of liver cancer varies enormously globally and unfortunately the burden of this nearly always fatal disease is much greater in the less economically developed countries of Asia and sub-Saharan Africa (2). HCC is also the most rapidly rising solid tumor in the US and Central America and is overrepresented in minority communities, including African-Americans, Hispanic/Latino-Americans and Asian-Americans (1,3,4). Overall, there are more than 850,000 new cases each year and more than 300,000 deaths annually in the People’s Republic of China (P.R.C.) alone (2). In contrast with most common cancers in the economically developed world where over 90% of cases are diagnosed after the age of 45, in high-risk regions for liver cancer onset begins to occur in both men and women by 20 years of age and peaks between 40-49 years of age in men and between 50-59 years of age in women (5-7). Gender differences in liver cancer incidence have also been well described and worldwide the number of cases among men were 554,000 and 228,000 among women in 2012 (8)(9). To date, the significant etiological factors associated with development of HCC have been defined by biomarker studies and they are infection in early life with hepatitis B virus (HBV) and lifetime exposure to high levels of aflatoxin B1 (AFB1) in the diet (10,11). Over the past 25 years, an appreciation for the role of the hepatitis C virus (HCV) has also emerged. HCV is contributing to HCC being the most rapidly rising solid tumor in the US and Japan (12). Detailed knowledge of the etiology of HCC has spurred many mechanistic studies to understand the pathogenesis of this nearly always-fatal disease (10,13,14). Fortunately, the successful development and deployment of some highly effective new drugs that cure HCV infection is a major advance and will hopefully diminish the role of this virus in liver cancer (15,16). Alcohol is a recognized human carcinogen and alcoholic cirrhosis and heavy alcohol use have been repeatedly associated with an increase in HCC risk (23). However, it is unclear if alcohol use in the absence of cirrhosis influences HCC development (24). Several studies have demonstrated an increased risk of HCC up to 5-fold with consumption of more than 80g of alcohol per day or approximately 6-7 drinks per day (23). The risk of HCC ranges from borderline significant to doubled with chronic alcohol consumption of less than 80g/day (23). A synergism between alcohol and HBV and HCV infections has also been described (23,25). In economically developed countries the dramatic rise in overweight and nonalcoholic fatty liver disease has also been related to increased HCC (26-28). Of major concern for the future are the role that obesity, diabetes and general underlying fatty liver disease will play in the development of liver cancer (29-31). Both therapeutic and pre-disease interventions will need to be deployed now to blunt the impact of these risk factors in the decades to come. Collectively, the development and validation of a new generation of biomarkers reflecting complex processes such as inflammation will need to be deployed.

Aflatoxin B1 (AFB1) production by Aspergillus flavus and Aspergillus parasiticus on ground Nyjer seeds: The effect of water activity and temperature

Nyjer oil seed cake supports high levels of aflatoxin B1 (AFB1) production. AFB1 is a secondary metabolite of Aspergillus flavus and A. parasiticus, classified as a Class 1A carcinogen. The aim of this study was to determine the effects of temperature (20, 27, and 35 °C) and water activity (0.82, 0.86, 0.90, 0.94, and 0.98 aw) on fungal growth and AFB1 production of A. flavus and A. parasiticus on ground Nyjer seeds over a 30-day incubation period.Linear regression models indicated that both fungal growth and AFB1 production were significantly influenced by water activity of Nyjer seeds and incubation temperature. The two fungi did not grow on Nyjer seeds at 0.82 aw at the three incubation temperatures. The most favorable growth conditions for both fungi were 0.90–0.98 aw at 27 °C or 0.90–0.94 aw at 35 °C. The optimum temperature for AFB1 production was 27 °C for both A. flavus and A. parasiticus (with regression coefficients of 6.01 and 9.11, respectively). Both fungi were likely to produce high levels of AFB1 at 0.90 aw (with regression coefficients of 3.56 for A. flavus and 7.17 for A. parasiticus). Aspergillus flavus only produced AFB1 on seeds with 0.90–0.98 aw at 27 °C (in the range of 203–282 μg/kg) and on seeds with 0.90 aw at 35 °C (212 μg/kg). No detectable AFB1 was produced by this fungus in any other culture conditions that were studied.Aspergillus parasiticus, in contrast, was able to produce AFB1 under all of the growth conditions. At 20 °C, this fungus produced the highest level of AFB1 (212 μg/kg) at high water activity (0.98 aw). At 27 °C, A. parasiticus produced high levels of AFB1 (in the range of 209–265 μg/kg) at a wide range of water activities (0.86–0.98 aw). In the entire study, the highest AFB1 concertation for A. parasiticus was detected on seeds incubated at high temperature (35 °C) and low water activity (0.86 aw). The findings of this study could help optimize the storage conditions of Nyjer oil seeds to reduce aflatoxin contamination.

Influence of plant density on toxigenic fungal and mycotoxin contamination of maize grains

Field trials were set up in the Belgrade area (Serbia) in 2013 and 2014 to determine the effect of plant density on the natural incidence of potentially toxigenic fungi and the level of mycotoxins, aflatoxin B1 (AFB1), deoxynivalenol (DON) and fumonisins (FBs) in two Serbian maize hybrids of the FAO maturity group 700 (ZP 735 and NS Zenit). Three plant density treatments, namely, 55,000 plants ha−1 (PD1), 64,000 plants ha−1 (PD2) and 75,000 plants ha−1 (PD3), were evaluated.The incidence of identified potentially toxigenic fungi of the genera Aspergillus, Fusarium, and Penicillium and the FB level increased significantly (P ≤ 0.01) at PD3. The effect of year was also significant (P ≤ 0.01) on the incidence of toxigenic fungi, as all fungal species had a higher incidence in 2014 than in 2013, with the exception of Aspergillus spp. that showed a significantly higher incidence in 2013. Levels of all tested mycotoxins were higher in 2014 than in 2013. The higher incidence of Fusarium graminearum, Fusarium proliferatum, Fusarium subglutinans, Fusarium verticillioides and Penicillium spp. and higher levels of AFB1 and FBs were observed in the hybrid ZP 735, whereas the hybrid NS Zenit had a higher incidence of Aspergillus spp. The effect of hybrids was not significant on the incidence of F. subglutinans and the DON level.These results indicated that the highest investigated plant density increased the fungal incidence and the FB level, especially in 2014. Although the two hybrids originated from the same FAO group, they differed in their effects on some toxigenic fungi and mycotoxins.

Association of farmers’ sorghum grain post-harvest handling practices with aflatoxin B1 and total fumonisin contamination in east Hararghe, Ethiopia

Improper farmers’ postharvest handling practices of sorghum grain coupled with adverse climatic conditions are conducive for fungal growth and toxin production. The objective of the present study was to investigate the association of farmers' sorghum grain postharvest handling practices with aflatoxin B1 and total fumonisin contamination in three districts (Babile, Haramaya and Kersa) of East Hararghe Zone, Ethiopia. A total of 90 sorghum grain samples were collected in two phases. Half of the total samples were collected from the threshing yards at the time of threshing and the other half of samples were collected from underground storage pits 5 - 6 months after storage in the year 2013/14. Quantification of the mycotoxins was done using enzyme-linked immunosorbent assay (ELISA). Farmers threshed their sorghum grain either on bare ground, on cow dung smeared ground or on canvas while the underground storage pits were differently managed in all the three study districts. Variation in mycotoxin contamination levels were evidenced from sorghum grain threshed on different grounds. The highest mean (8.52 μg kg-1 grain) aflatoxin B1 and mean total fumonisin (1085.1 μg kg-1 grain) were detected from Babile sorghum grain samples threshed on bare ground. The highest total fumonisin (2002.8 μg kg-1grain) was detected from Haramaya sorghum grain samples threshed on bare ground close to the farmers’ sorghum fields. The variation was also observed in sorghum grain samples collected from the underground storage pits. High levels of aflatoxin B1 and total fumonisin were recorded from sorghum grain samples collected from bare underground storage pits in all the three study districts. Use of bare underground storage pits for sorghum grain storage showed a high risk of mycotoxin contamination. The findings of this study call for intervention strategies to be implemented by subsistence farmers to reduce the contamination by aflatoxin B1 and total fumonisin.

Aflatoxin B1 exposure and the risk of hepatocellular carcinoma in Iranian carriers of viral hepatitis B and C

Hepatocellular carcinoma (HCC) is known as one of the common and fatal cancers in the Asian and African countries. Two significant factors could cause this type of cancer including having diets contaminated with aflatoxin and chronic viral hepatitis infections. This study aimed to compare the level of aflatoxin B1 (AFB1) in those who had viral hepatitis B- and C-related HCC as a case group and a group of patients with chronic hepatitis B or C infections as the control group. This case-control study was conducted on 82 patients including 41 patients with viral hepatitis-related HCC and 41 patients with chronic hepatitis B or C infections. Level of AFB1 was measured using ELISA and compared between groups. Most of the patients in both groups were male and infected with HBV. The patients with HCC with mean age 57.5 years were significantly older than those in the control group with mean age 44.8 years (p < .05). Aflatoxin B1 was detected in 32 (78%) samples in HCC group and 28 (68.3%) samples in non-HCC group (p > .05). The median (IQR) for AFB1 levels in HCC group was 3.87 (3.46) pg/mL, while it was 2.63 (3.14) pg/mL in the control group (p = .018). Our results demonstrate for the first time the exposure to high levels of AFB1 in Iranian patients with HCC which indicate the possible involvement of AFB1 as a major risk factor in the etiology of HCC in patients with hepatitis B and C.

A Study of MicroRNA-24 Expression in Aflatoxin B1 Exposed Patients with Hepatocellular Carcinoma and Cirrhosis

Introduction: Over 80% of hepatocellular carcinoma (HCC) sufferers occur in developing countries as a result of exposure to hepatitis B or C viruses, through formation of cirrhosis or viral integration into host DNA on the part of HBV, or due to ingestion of aflatoxin B1 (AFB1) causing DNA damage in hepatic tissue with generation of mutations, particularly in p53 tumor suppressor gene. MicroRNAs are noncoding RNAs that have an effect on oncogene and tumor suppressor gene expression, hence partaking in carcinogenesis. A connection between HCC and dysregulated expression of microRNAs has been repeatedly demonstrated, suggesting that circulating microRNAs might potentially be used as biomarkers for pre-clinical HCC detection. We aimed in this study to assess the role of micro-ribonucleic acid-24 (microRNA-24) expression in patients with cirrhosis and HCC who have experienced high levels of AFB1 exposure.Materials and Methods: Fifty HCC and 24 hepatic cirrhosis patients, in addition to 20 healthy control subjects were included in this study. Aflatoxin B1 was measured by enzyme-linked immunosorbent assay (ELISA) and microRNA-24 was detected using real-time polymerase chain reaction (real-time PCR).Results: Both aflatoxin B1 levels and microRNA-24 expression were found to be significantly increased in all patient groups in comparison to controls, more so in the HCC than cirrhotic group (p˂0.0001). A highly significant correlation was detected between levels of AFB1 and amount of microRNA-24 expressed in both patient groups relative to their control counterparts (p˂0.0001). Receiver Operating Characteristic (ROC) curve performed to evaluate the ability of microRNA-24 to differentiate between HCC and cirrhosis showed that it had sensitivity of 80% and specificity of 63% at cutoff 1.3, which was highly significant (p˂0.0001).Conclusion: Increased aflatoxin B1 levels detected in patients with cirrhosis and HCC further support previous studies evaluating the level of exposure of the Egyptian population to this carcinogen and support the critical role of aflatoxin B1 in the appearance of HCC. In addition, microRNA-24 expression levels demonstrated in both cirrhosis and HCC might be valuable for use as a noninvasive diagnostic tool for diagnosis of HCC.

Survey of mycotoxins in retail market cereals, derived products and evaluation of their dietary intake

In current study a total 229 samples of cereal products, available in retail markets of main cities of Punjab, Pakistan were collected for the analysis of mycotoxins. The analysis was performed using reverse phase HPLC with fluorescence detector. The results have shown that 121 (53%) out of 229 samples of cereal products have found positive for aflatoxin B1 (AFB1) and total aflatoxins (AFs). Samples of 22 and 12% were found higher than the maximum level for AFB1 and total AFs. The highest level of AFB1 and total AFs was found in porridge samples i.e 3.90 ± 0.039 μg kg−1 and 5.60 ± 0.005 μg kg−1, respectively. About 115 (50%) out of 229 samples of cereal products were found positive with ochratoxin A (OTA) and 26% samples were found to be higher than the maximum level of 3 μg kg−1. About 130 (57%) samples of cereal were found contaminated with zearalenone (ZEN) and 31% of samples were found higher than the maximum level of 50 μg kg−1. The highest mean level of 21.45 ± 1.90 μg kg−1 of ZEN was found in Suji (Semolina) samples. The estimated average exposure dose of AFB1, OTA and ZEN based on our daily food consumption data were 3.50, 3.85 and 29 ng kg−1 bw day−1 found in some cereal samples, respectively. The calculated excess risk of liver cancer incidence by ingestion of cereals containing AFB1 was 1.66 per 100,000 adults per year.

Occurrence of aflatoxins and its management in diverse cropping systems of central Tanzania

The staple crops, maize, sorghum, bambara nut, groundnut, and sunflower common in semi-arid agro-pastoral farming systems of central Tanzania are prone to aflatoxin contamination. Consumption of such crop produce, contaminated with high levels of aflatoxin B1 (AFB1), affects growth and health. In this paper, aflatoxin contamination in freshly harvested and stored crop produce from central Tanzania was examined, including the efficacy of aflatoxin mitigation technologies on grain/kernal quality. A total of 312 farmers were recruited, trained on aflatoxin mitigation technologies, and allowed to deploy the technologies for 2 years. After 2 years, 188 of the 312 farmers were tracked to determine whether they had adopted and complied with the mitigation practices. Aflatoxigenic Aspergillus flavus and aflatoxin B1 contamination in freshly harvested and stored grains/kernels were assessed. A. flavus frequency and aflatoxin production by fungi were assayed by examining culture characteristics and thin-layer chromatography respectively. AFB1 was assayed by enzyme-linked immunosorbent assay. The average aflatoxin contamination in freshly harvested samples was 18.8 μg/kg, which is above the acceptable standard of 10 μg/kg. Contamination increased during storage to an average of 57.2 μg/kg, indicating a high exposure risk. Grains and oilseeds from maize, sorghum, and sunflower produced in aboveground reproductive structures had relatively low aflatoxin contamination compared to those produced in geocarpic structures of groundnut and bambara nut. Farmers who adopted recommended post-harvest management practices had considerably lower aflatoxin contamination in their stored kernels/grains. Furthermore, the effects of these factors were quantified by multivariate statistical analyses. Training and behavioral changes by farmers in their post-harvest practice minimize aflatoxin contamination and improve food safety. Moreover, if non-trained farmers receive mitigation training, aflatoxin concentration is predicted to decrease by 28.9 μg/kg on average.

Occurrence of aflatoxin B1 in baby foods marketed in Iran.

Aflatoxin B1 (AFB1 ), a toxic fungal metabolite that is found in baby foods, can lead to serious complications for children's health. In the present study, 48 commercial baby foods available in the Iranian market were investigated for the presence of AFB1 using a high performance liquid chromatography system that was equipped with post-column photochemical derivatization and a fluorescence detector. Thirty-three out of 48 samples (68.7%) were contaminated with AFB1 at median, maximum and mean concentration levels of 0.11, 15.15 and 2.602 ± 4.065 µg kg-1 , respectively. The AFB1 concentration in 39.6% of the samples was higher than the maximum level established in Iran for AFB1 within baby foods containing milk (0.5 µg kg-1 ). The incidence of AFB1 in rice, wheat and multigrain infant cereal samples was 90%, 25% and 100%, respectively, whereas rice-based baby foods contained the highest levels of AFB1 . In the present study, the finding of both high rates and high levels of AFB1 in cereal baby foods indicates the need to reduce AFB1 contamination in these products. Therefore, further monitoring and control of pre- and post-harvest, storage, and manufacturing processes is required. © 2016 Society of Chemical Industry.

Acute Aflatoxicosis in Swines in Northeastern Brazil

Background: Aflatoxins are hepatotoxic mycotoxins derived from the secondary metabolism of toxigenic fungi belonging to the genus Aspergillus, especially A. flavus and A. parasiticus. Aflatoxin B1 is the most important metabolite, because of its deleterious effect mainly to the liver, especially for its carcinogenic, mutagenic and haemorrhagic properties, and usually is detected in higher concentrations in contaminated substrates. This paper reports the epidemiological, clinical, pathological and toxicological aspects of an outbreak of acute aflatoxicosis in pigs raised in Northeastern Brazil.Case: The cases occurred in a complete cycle farm, in the city of Mossoró, Rio Grande do Norte, Northeastern Brazil, in pigs ingesting low quality (moldy) corn being produced and processed on the farm. Sixty (73.1%) out of 82 two to five-months old pigs were clinicaly affected and 54 (65.8%) died. All animals showed fever, weight loss, tachycardia, tachypnea, lethargy, muscle tremors, muscle weakness and diarrhea. The clinical course ranged from five to 48 hours. Adult pigs were not affected. At necropsies, generalized jaundice, ascites, hydropericardium, petechial hemorrhages in the mesentery, subcutaneous edema and mesocolon were observed. The liver was yellow-orange with reddish diffuse multifocal areas, enlarged and extremely friable. Histologically there was swelling of hepatocytes with severe diffuse hepatocellular fatty degeneration, centrilobular hepatocellular necrosis, proliferation of bile ducts and cholestasis. High concentrations of aflatoxin B1 were determined in the corn (3400 μg/kg) and ration (1460 μg/kg).Discussion: The diagnosis of aflatoxicosis was based on epidemiological investigation associated with clinical and pathological findings and confirmed by high levels of aflatoxin B1 found in samples of corn and feed. Of the numerous types of aflatoxin reported, the most common is the B1, which is typically produced by Aspergillus fungi. In intensive pig farms, management conditions increase the chances of occurrence of intoxications caused by the poor quality of the grain (especially maize) by the poor quality of the grain (especially maize) used in the diet formulation. In the present report the corn was severely degraded and kept in physical conditions that favor the proliferation of aflatoxins. In addition, young animals, which are more suseptible, were the only ones affected with 73% morbidity and 65.8% mortality. In cases of spontaneous aflatoxicosis morbidity in pigs can vary from 10 to 100% and mortality is high when the diet has a high concentration of aflatoxins as observed in this outbreak (3400 and 1460 μg/kg of B1 in corn and food, respectively) . Increases in sérum ALT levels indicate hyperacute, acute or chronic active hepatocellular damage; a toxic hepatitis in this case. Furthermore, the increased serum AST suggest the existence of extensive and progressive hepatocellular damage, because this enzyme is synthesized mitochondrial level. Legislation in Brazil, determines that the maximum tolerated aflatoxin concentrations are 50 parts per million (ppm) or 50 μg/kg in food included in the diet formulation for animal consumption and 20 ppb in corn grain for human consumption. Differential diagnosis of aflatoxicosis include leptospirosis and intoxication by Crotalaria retusa or other pyrrolizidine alkaloids-containing plants.Keywords: aflatoxicosis, mycotoxins, toxic hepatitis, swine.

Multiple mycotoxin co-occurrence in maize grown in three agro-ecological zones of Tanzania

In this study, the co-occurrence of multiple mycotoxins in maize kernels collected from 300 households' stores in three agro-ecological zones in Tanzania was evaluated by using ultra high performance liquid chromatography/time-of-flight mass spectrometry (TOFMS) with a QuEChERS-based procedure as sample treatment. This method was validated for the analysis of the main eleven mycotoxins of health concern that can occur in maize: aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), ochratoxin A (OTA), deoxynivalenol (DON), fumonisin B1 (FB1), fumonisin B2 (FB2), HT-2 toxin, T-2 toxin and zearalenone (ZEN). From each zone one major maize producing district for home consumption was chosen and 20 villages for each district were randomly selected for sampling. All mycotoxins of health concern, except for T-2 toxin, were detected in the maize samples. Particularly high levels of AFB1 (50%; 3–1,081 μg kg−1), FB1 (73%; 16–18,184 μg kg−1), FB2 (48%; 178–38,217 μg kg−1) and DON (63%; 68–2,196 μg kg−1) were observed. Some samples exceeded the maximum limits set in Tanzania for aflatoxins or in European regulations for other mycotoxins in unprocessed maize. Eighty seven percent of samples were contaminated with more than one mycotoxin, with 45% of samples co-contaminated by carcinogenic mycotoxins, aflatoxins and fumonisins. Significant differences in contamination pattern were observed among the three agro-ecological zones. The high incidence and at high levels (for some) of these mycotoxins in maize may have serious implications on the health of the consumers since maize constitute the staple food of most Tanzanian population. Effective strategies targeting more than one mycotoxin are encouraged to reduce contamination of maize with mycotoxins.