Aflatoxin Levels Research Articles

An integrated model for pre- and post-harvest aflatoxin contamination in maize

Aflatoxin contamination caused by colonization of maize by Aspergillus flavus continues to pose a major human and livestock health hazard in the food chain. Increasing attention has been focused on the development of models to predict risk and to identify effective intervention strategies. Most risk prediction models have focused on elucidating weather and site variables on the pre-harvest dynamics of A. flavus growth and aflatoxin production. However fungal growth and toxin accumulation continue to occur after harvest, especially in countries where storage conditions are limited by logistical and cost constraints. In this paper, building on previous work, we introduce and test an integrated meteorology-driven epidemiological model that covers the entire supply chain from planting to delivery. We parameterise the model using approximate Bayesian computation with monthly time-series data over six years for contamination levels of aflatoxin in daily shipments received from up to three sourcing regions at a high-volume maize processing plant in South Central India. The time series for aflatoxin levels from the parameterised model successfully replicated the overall profile, scale and variance of the historical aflatoxin datasets used for fitting and validation. We use the model to illustrate the dynamics of A. flavus growth and aflatoxin production during the pre- and post-harvest phases in different sourcing regions, in short-term predictions to inform decision making about sourcing supplies and to compare intervention strategies to reduce the risks of aflatoxin contamination.

Investigation of total aflatoxin in nuts and dried fruits and consumption habits during pregnancy in Türkiye

Background: During pregnancy, adequate energy, nutrient intake, and food safety are important. Aims: This study aimed to examine the presence of aflatoxin, which has toxigenic properties, in nuts and dried fruits consumed during pregnancy. Subjects and Methods: Forty-five pregnant women living in Istanbul and Balikesir cities provinces, who were selected using the convenience sampling method, were applied face-to-face interview method on their attitudes and behaviors regarding their preferences for consuming nuts and dried fruits and storage conditions between February and April 2022. For aflatoxin analysis, the samples were taken from the nuts and dried fruits consumed by the pregnant women. The total aflatoxin content in the samples was analyzed by the ELISA method with a quantitative aflatoxin high-sensitivity test kit. Results: The most commonly consumed nuts by pregnant women during pregnancy; were walnuts and hazelnuts, respectively. It was determined that pregnant women buy nuts and dried fruits first from the nut shop and second from the market. Regarding storage preferences, it was seen that the participants mostly stored the nuts in the closed kitchen cabinet or refrigerator cabinet. For the storage material preferences, glass, porcelain, and packaging were preferred. For aflatoxin results, no detectable level of aflatoxin was found in 35 samples, and the presence of aflatoxin in 3 samples (1.43 ppb, 1.523 ppb, and 1.804 ppb, respectively) was detected. Conclusion: Nuts and dried fruit consumption preferences of pregnant women differed according to the products. No aflatoxin was found in the nuts and dried fruits at a level that could threaten the health of pregnant women. Keywords: Aflatoxin, Nuts, Dried Fruits, Pregnancy, ELISA method

Aflatoxin detoxification by biosynthesized iron oxide nanoparticles using green and black tea extracts

Researchers have recently been interested in employing nanoparticles (NPs) obtained from herbal extracts through green synthesis for various applications. This study investigated the detoxification of aflatoxins, which are toxic substances produced by molds Aspergillus flavus and Aspergillus parasiticus. The present work examined the levels of aflatoxins in hazelnut and peanut puree. Turkish black tea extract (BTE), Turkish green tea extract (GTE), green synthesized black tea-based iron oxide nanoparticles (BTFeONPs), and green tea-based iron oxide nanoparticles (GTFeONPs) were produced for aflatoxin removal. Characterizations and various antioxidant and antimicrobial activities of the tea extracts and iron oxide nanoparticles (FeONPs) were investigated. The aflatoxin levels of hazelnut puree used for this study were 6.57 ± 0.06 µg/kg for aflatoxin B1 and 13.03 ± 0.16 µg/kg for total aflatoxin, whereas the aflatoxin levels of (AFLB1) peanut puree were 7.79 ± 0.15 µg/kg for AFLB1 and 15.21 ± 0.12 µg/kg for total aflatoxin. Using soluble BTE resulted in a 40 to 50% decrease in aflatoxin levels in hazelnut and peanut purees, while soluble GTE led to a 30 to 45% decrease. Meanwhile, using BTFeONPs and GTFeONPs resulted in a 33 to 48% and 40 to 50% decrease, respectively, in aflatoxin levels in hazelnut and peanut purees.

Antioxidant And Anti-Mycotoxin Activities, And Cytotoxicity Properties In Vitro Of Propolis Extracts

Abstract: The present study aims to determine the antioxidant activity and cytotoxic activity of propolis and evaluate the anti-mycotoxin activity of different propolis extracts. The three extracts of propolis (ethyl acetate, ethanol (75%), and water) were subjected to testing of the antioxidant potential, and total phenolic and flavonoid contents. determination of the cytotoxicity activity by standard cell culture method against colon and liver and the ability of propolis extracts to control aflatoxin (AF) production. The results revealed that the highest value of antioxidant activities was found for propolis ethyl acetate extract with an average % inhibition of 63.42%. the highest amount of propolis's total phenolic and flavonoid contents using ethyl acetate extract were 149.5 µg gallic acid equivalent/mg extract and 218.1 µg quercetin equivalent/mg extract, respectively. The three propolis extracts affect liver and colon human cell cancer. Ethyl acetate extract of propolis showed the lowest IC50 with the highest anti-cancer activity on the liver cancer cell line. In comparison, water extract showed the lowest IC50 with the greatest anticancer activity on the colon cancer cell line (50 and 54 µg/ml, respectively). Using different concentrations of propolis to reduce AF levels led to the complete disappearance of AF production at 100, 200, and 400 mg/ml concentrations of Ethyl acetate extract against AF production. In conclusion, these obtained findings indicated that propolis extracts exhibited substantial antioxidant and anti-cancer activities.

338 A Survey of Mycotoxin Occurrence in Us Corn and Corn By-Product Feed Ingredients from 2018 to 2022 Harvest Years

Abstract The aim of this survey was to compare the occurrence and contamination levels of six major mycotoxin categories found in corn and corn by-product feed ingredients harvested in the United States from 2018 through 2022. Mycotoxins are secondary fungal metabolites that can negatively impact animal health and performance and have been routinely found in a variety of feedstuffs including, but not limited to, cereal grains, by-products, silages, dry hays and pasture grasses. Mycotoxin categories evaluated in this survey included: aflatoxins (AFLA), type A trichothecenes (A-Trich), type B trichothecenes (B-Trich), fumonisins (FUM), zearalenone (ZEN), and ochratoxin A (OTA). This study includes data from corn samples labeled as 2022 harvest and corn b-product feed ingredients submitted from October 2022 through March 2023 and were analyzed for 17 different metabolites via the Liquid Chromatography with tandem mass spectrometry (LC-MS/MS) method. Samples that tested above the limit of detection for each mycotoxin group were analyzed using the generalized linear mixed model procedure of SAS (SAS 9.4, Cary, NC) using harvest year as a fixed effect. The effect of harvest year on average contamination level for each mycotoxin is presented in Table 1. For 2022 harvest year, 260 corn samples and 66 corn by-product samples have been evaluated to date. Mean B-Trich, ZEN, FUM and AFLA levels (parts per billion, ppb) for corn grain samples were similar in 2022 as previous years (P > 0.05). However, for corn grain samples, FUM prevalence and concentration were numerically greater in 2022 than in 2021 and 2020. In the 66 samples of corn by-products, FUM was found in all the samples (100%) and B-Trich were found in the majority of the samples (97%). Mean concentration of FUM in 2022 corn by-product samples was greater (P < 0.001) compared with 2021. Preliminary results of this survey suggest mycotoxin occurrence and contamination remains similar to previous harvest years except for greater mean FUM concentration levels in corn and corn by-products feed ingredients.

Safety improvement of the open sun dried Egyptian Siwi dates using closed solar dryer

Egyptian Siwi dates dried using the open sun drying is exposed to different contaminants. So, the current study aims to use the closed solar dryer to improve Siwi date safety. The impact of washing and closed solar drying on the levels of microbial load, aflatoxins and heavy metals in Egyptian Siwi dates (ESD), in comparison to traditional open sun drying methods were examined. Two different drying techniques were employed to dry 300 kg of ESD. The microbial load was assessed following the two drying procedures. The levels of aflatoxins and heavy metals were analyzed using High-performance liquid chromatography (HPLC) and Inductively Coupled Plasma (ICP) techniques, respectively, after both drying methods. Additionally, the influence of storage time on the microbial load of the ESD was also evaluated using standard methods. The findings of the current study demonstrated that the closed solar drying significantly reduced the total bacterial and fungal counts by 96 % and 93 %, respectively, when compared to open sun-drying. No aflatoxins were detected in both fresh Siwi dates and Siwi dates dried using closed solar drying. However, after open sun drying, two aflatoxins; aflatoxin B1 (AFB1) and aflatoxin G1 (AFG1), were detected in the ESD, with concentrations of 0.95 and 0.23 μg kg−1, respectively. The closed solar drying significantly decreased the levels of lead (Pb), cadmium (Cd), copper (Cu), nickel (Ni), chromium (Cr), zinc (Zn), manganese (Mn), and iron (Fe) in the dried dates by 96 %, 94 %, 48 %, 71 %, 64 %, 4 %, 26 %, and 7 %, respectively, when compared to open sun drying. The stored Siwi dates that was exposed to the open sun drying showed a higher increase in bacterial (4.86 log CFU/g) and fungal (4.46 log CFU/g) counts. However, the stored Siwi dates that was exposed to the closed solar dryer showed a lower increase in bacterial (3.21 log CFU/g) and fungal (2.51 log CFU/g) counts. So, the duration of storage significantly impacted the microbial loads of the closed solar dried dates as compared to open sun drying. Overall, closed solar drying reduced the levels of investigated contaminants and extended the shelf life of ESD, thereby enhancing their safety for human consumption.

Aflatoxin levels in poultry feed: a comparison of mash and pellet forms

The current research was conducted to determine the aflatoxigenic and non-aflatoxigenic Aspergillus flavus isolates and the frequency of aflatoxin levels (B1, B2, G1, G2), in main feed ingredients (corn and soybean meal) and poultry finished feed (in mash and pellet forms). Eighty-five samples of corn, soybean meal, and poultry finished feed was randomly collected from feed mills in Iran. Regarding macro and microscopic morphological criteria, Aspergillus isolates were identified, and aflatoxins were determined by thin layer chromatography (TLC) and high-performance liquid chromatography (HPLC). All of poultry feed samples were contaminated with different levels of aflatoxins, ranging from ND (they were not detected in those samples) to 5.58 µg/kg. At all stages of processing, the poultry feed had lower levels of aflatoxins in comparison with the accepted/residue levels of poultry feed mills. Higher amounts of aflatoxins (B1, B2, G1, G2, and total) were detected in pelleted feed, compared to other poultry samples (P < 0.05). The total toxin level in mash feed samples reached a maximum of 3.31 ppb. The results indicate that finished feed samples in pellet form may pose a greater risk than their individual ingredients in poultry feed, particularly when suboptimal conditions exist for eliminating fungal populations. So, the prevention and reduction of (Aspergillus section Flavi) are highly important in maintaining quality control of poultry feed, as the production of aflatoxins can occur during the process of converting raw ingredients into finished feed.

Microbial load and aflatoxin contamination in locally formulated herbal mixtures obtained from Itoku market, Nigeria

Contamination of locally formulated herbs with aflatoxins and pathogenic organisms poses major health concerns to humans and animals, especially in recent times when herbal mixtures are on the rise. This study aimed to determine the herbs' microbial profile and aflatoxin level. Two different herbal medicines (malaria and typhoid; each prepared with water and alcohol) were obtained at Itoku market, Ogun-state, Nigeria. The samples were isolated using the serial dilution technique and isolates were identified morphologically. Aflatoxin quantification was done on the herbal samples using High-Performance Liquid Chromatography (HPLC). The viable bacteria count ranged from 1.0×105 cfu/g to 20.0×105 cfu/mL with the typhoid herbs prepared with water recording the highest count. The microorganisms obtained in the herbs were confirmed as, Escherichia coli, Staphylococcus aureus, Micrococcus luteus, Salmonella sp, Proteus sp, Aspergillus flavus, Penicillium chrysogenum, Saccharomyces cerevisae and Fusarium sp. Typhoid herbs prepared with water showed high aflatoxin detection limits of 7.60 μg/mL. The result showed that the locally formulated herbs were highly contaminated with microorganisms and that consumption of the locally formulated herbs with aflatoxin could cause aflatoxicosis.

Physiological Response and Aflatoxin Contamination in Maize (Zea Mays L.) Grown Under Varying Water-Deficit Levels in a Semi-Arid Region

The present study explored the effects of water deficit levels at different growth stages of maize (Zea mays L.) cultivated in semi-arid conditions with regard to physiological responses and aflatoxin contamination. The physiological growth changes of maize hybrids were gauged for parameters viz. relative water content (RWC, %), root-shoot ratio (R/S), and specific leaf area (SLA). At the same time, the study used HELICA total Aflatoxin Assay for estimating aflatoxin contamination in the produced maize kernel. Results revealed the third level of water-deficit, which extended to the dent stage, led to lower RWC%, and higher (R/S), alongside lower (SLA). Although the aflatoxin level was estimated to be 18.5 ppb in the maize kernels (FDA limit = 20 ppb), it was apparent that cultivation in a semi-arid condition runs the risk of aflatoxin contamination, likely due to water shortage and high growing temperatures.

Effectiveness of complementary sorting methods in reducing aflatoxin contamination in groundnuts

Abstract Aflatoxin contamination of staple foods remains a public health concern in many tropical and sub-tropical countries. In sub-Saharan Africa, groundnuts are a significant source of aflatoxin (AF) in vulnerable populations such as infants and young children. However, there are limited scalable and affordable technological interventions to reduce the risk of aflatoxin ingestion in low and middle-income contexts. This study compared the effectiveness of complementary sorting methods in reducing AF contamination, time taken, and percentage loss of groundnuts. The study also evaluated bulk density and kernel weight as proxies for AF. Groundnuts were sampled from 19 bags at a medium-scale enterprise in Tanzania (Halisi) that processes cereal-based blended flours for complementary feeding. The samples were subjected to six sorting methods: (1) size (S) sorting, which yielded large and small fractions (n = 38); (2) density (D) sorting, which yielded heavy and light fractions (n = 38), (3) visual (V) sorting, (4) the combination of size and visual (SV), (5) the combination of density and visual (DV), and (6) the combination of size, density, and visual (SDV) which yielded grades 1, 2, 3, and 4 (n = 76). Samples of unsorted groundnuts and grades from all six sorting regimes (n = 418) were analysed for total aflatoxin by enzyme-linked immunosorbent assay. Analysis of variance (ANOVA) at a 5% significance level was used to compare AF reduction efficiency. Aflatoxin levels were reduced by 99% for the highest grade (G1) by the SDV sorting method. The SDV sorting method was the most effective in reducing AF contamination by removing 14% outsort (Grade 4) from 1 kg groundnut within 22 min. Bulk density and 100 kernels weight were inversely associated with AF, indicating their value as AF proxies. Scaling up such low-cost sorting methods can significantly reduce AF along the value chain and improve food safety.

Levels of total aflatoxins in maize and groundnuts across food value chains, gender and Agro-ecological zones of Uganda

Maize and groundnuts are traditional nutrient-rich and high economic value foods grown in Uganda. However, these crops are susceptible to aflatoxin contamination which may result into aflatoxicosis related illnesses. Occurrence of flatoxins in the foods varies across food value chains, gender and agro-ecological zones of Uganda. Therefore, we conducted a cross-sectional study in 80 maize and groundnut foodstuff from Masindi and Soroti agro-ecological districts respectively. We determined levels of total aflatoxins in maize and groundnut samples across food value chains, gender and agro-ecological zones. This was aimed at assessing safety and quality status of the foods in Uganda. Questionnaires were administered to obtain information on food handling practices. 500g of each food sample were obtained and analyzed for total aflatoxin levels using ELISA assay. Data was analyzed using descriptive and analytical statistics. In overall, 45% of maize and 30% of groundnut foods were contaminated with aflatoxins. Mean aflatoxin levels in foods from Eastern and Western agro-ecological zones were 0.052±0.036ppb and 0.045±0.033ppb respectively (p=0.124). Mean aflatoxin levels in groundnuts from both male and female respondents were coincidentally 0.052ppb. Whereas, the mean aflatoxin levels in maize from male and female respondents were 0.056±0.037ppb and 0.039±0.029ppb respectively. Across the food value chain, wholesaler groundnut foods contained the highest mean aflatoxin levels of 0.088ppb (p= 0.27). Growing high polyamine containing crops, routine testing of aflatoxin prone foods and sensitizing food value chain players are important aflatoxin control strategies.

Aflatoksin: Aspek kesehatan, metode reduksi dan deteksinya

Food contaminant aflatoxin is a mycotoxin produced by Aspergillus flavus and A. parasiticus. This article aims to discover the pathophysiological, immunological, pharmacological, toxicity, and reduction and detection methods of aflatoxin. Kinds of literature were obtained from Research Gate, Pubmed, and Science Direct with the primary keyword “aflatoxin”. Pathophysiologically, aflatoxin-contaminated food has been proven to cause necrosis in liver cells, developing into liver cancer. Immunologically, aflatoxin decreases monocyte and dendritic cell phagocytosis, neutrophil cell ATP production, and pro-inflammatory cytokine synthesis. Aflatoxin toxicity is at the LD50 of 12-16 mg/kg b.w, causing death. Pharmacologically, 120-201 µg/kg b.w causes aflatoxicosis, in vivo studies indicated that NovaSil, Sulfarophan, and Monanthotaxis caffra leaf extract may reduce its toxicity. Aflatoxins are highly thermostable; hence, once food has been contaminated, they cannot be destroyed by normal cooking process. The control and reduction should be conducted in post-harvest handling, common physical means practiced are heating, drying, and smoking. Chemically using ozone, 0.5 sodium bisulfate, 1% sodium hydroxide, 5% acetic acid, and prochloraz. Biologically using Flavobacterium aurantiacum B-184, Bacillus velezensis DY3108, and, a consortium of Geobacillus and Tepidimicrobium bacteria. Aflatoxin can be detected using TLC, HPLC, MS, ELISA, and UHPLC-ESI MS/MS. The prevention of aflatoxin occurrence is done through good post-harvest handling, good manufacturing practices, and applying regulations accordingly to ensure food products and feed are at acceptable levels of aflatoxin.

Tahran, İran'da yüksek performanslı sıvı kromatografi ile süt ve süt ürünlerinde aflatoksin M1 içeriğinin değerlendirilmesi

Aflatoxin M1 (AFM1) is the most important aflatoxin in milk and dairy products, which is carcinogenic and hepatotoxic. This study aimed to evaluate the AFM1 content in the milk and distributed dairy products in Tehran. 75 samples, including 15 samples of raw milk, 15 samples of pasteurized milk, 15 samples of ultra-high temperature milk, 15 samples of pasteurized yogurt, and 15 samples of pasteurized cheese, were collected from October to December 2020 in Tehran by simple random sampling. The dietary exposure or estimated dietary intake (EDI) and hazard index (HI) were calculated for milk and dairy product consumers. The AFM1 content in the samples was determined by using high-performance liquid chromatography (HPLC) along with a fluorescence detector. AFM1 was observed in all samples. The values of AFM1 in all samples were higher than the acceptable range determined by the European Union. 100% of milk and yogurt samples and 82% of cheese samples exceeded the Iranian maximum limit (100 ng kg-1 in milk and yogurt, and 250 ng Kg-1 in cheese). Mean AFM1 content in raw milk samples, pasteurized milk samples, UHT milk samples, pasteurized yogurt samples, and pasteurized cheese samples were 337±17.7, 306±15.5, 305±17.4, 320±17.6, and 309±18.5 ng Kg-1, respectively. The highest value of HI was observed in children of Tehran, Iran. Based on the results, the aflatoxin content in milk and distributed dairy products in Tehran in the autumn is inconvenient. It is recommended that the aflatoxin levels should be measured at different times of the year, especially in raw milk, and feed monitoring is intensified for contamination with toxin-producing molds.

Nijerya Kwara eyaletinde seçilmiş iki soğuk oda işletmesinde Scomber scombrus ve Clupea harengus’taki aflatoksin, bakteri ve ağır metal birikimi

Impurities found in fish have been a major cause of disease and illness to consumers. This study's objective was to evaluate the total aflatoxin, heavy metal and microbial load in two frozen fish: Scomber scombrus and Clupea harengus from two (2) cold room facilities in Omu-Aran and Ilorin. Heavy metals, aflatoxin and microbial load were investigated using standard methods. Health risk was also determined using health risk index (HRI), daily intake of metals (DIM), and health quotient (HQ), and total toxicity of metals (TTM). Cd, Cu, Ni, Pb, Mn and Cr did not differ significantly (p&gt;0.05) in both species from both locations. Nickel was lower than the recommended limit by World Health Organization (WHO). Level of Mn and Cr were higher in both species. Mn load was higher in the muscles of the sampled fish than in the gills from September through to November with highest value of 1.26±0.08 and 1.30±0.12 obtained for S. scombrus and C. harengus. Highest concentrations of all metals was observed in the gills except manganese and copper [Cd = 0.03 (S. scombrus), Cr = 1.22±0.13 (S. scombrus), Ni = 0.025±0.04 (S. scombrus), Pb = 0.06±0.02 (S. scombrus)]. HRI was &gt; 1 in the different age groups for the different metals. TTM was &gt; 1 in both species. Total aflatoxin level was higher in the gills (4.25 – 5) ppb than in the muscle (1.5 - 3) ppb for both locations respectively. Vibrio spp. and non-coliform bacteria were high in both species from both locations. The study concludes that heavy metal loads (Mn, Cd, Cu, Cr, and Ni) were more than the permitted limitations imposed by FAO, WHO and EU legislation for fish and fish products placing consumers at health risk.

Incidence of Aflatoxins and Ochratoxin A in Wheat and Corn from Albania.

In this study, aflatoxins (AFs) and ochratoxin A (OTA) were analyzed in grains, specifically wheat and corn, from Albania. To summarize, 71 wheat and 45 corn samples from different growing areas were collected. The multi-toxin analytical procedure involved sample extraction and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The incidence of AF was 18% in the analyzed wheat and 71% in the corn samples. The concentration of AFs was much higher in the corn samples than in the wheat samples. The maximum permitted levels for aflatoxin B1 (AFB1) and total AFs were not exceeded in the wheat samples, while they were exceeded in 36% of the corn samples. In the wheat samples, the AFB1 concentration varied between 0.2 and 0.4 µg kg-1. However, the highest concentrations in the corn samples were 2057, 2944, and 3550 µg kg-1. OTA was present in only three corn samples and one wheat sample. However, all contaminated samples exceeded the maximum permitted levels. This report reveals the presence of AFs and OTA in grain commodities, specifically wheat and corn, grown in Albania.

Presence, Co-Occurrence, and Daily Intake Estimates of Aflatoxins and Fumonisins in Maize Consumed in Food-Insecure Regions of Western Honduras.

Foodborne mycotoxins are a significant food safety risk in developing countries. Our objective was to determine the occurrence of and exposure levels to aflatoxins (AFs) and fumonisins (FBs) in maize intended for human and animal consumption in food-insecure regions of western Honduras. Total AFs and FBs were quantified with a monoclonal antibody-based affinity spectrofluorimetric method. FBs were detected in 614/631 samples of maize destined for human consumption at 0.3 to 41 mg/kg (mean, 2.7 mg/kg). Of the 614 positive samples, 147 had FB levels exceeding the U.S. Food and Drug Administration (FDA) advisory threshold of 4.0 mg/kg. AFs were detected in 109/631 samples of maize for human consumption with concentrations between 1.0 and 490 µg/kg (mean, 10 µg/kg). AF levels in 34 samples exceeded the FDA regulatory limit (i.e., 20 µg/kg). The average probable daily intake of AFs in western Honduras ranged from 0 to 260 ng/kg body weight/day, and for FBs, the average probable daily intake ranged from 17 to 53 μg/kg body weight/day. AFs and FBs co-occurred in 106/631 samples with 60 samples containing both toxins at levels greater than the FDA regulatory levels. Samples of maize intended for animal feed had significantly higher AF (mean, 22 µg/kg) and FB (mean, 7.6 mg/kg) contamination levels than those observed in samples destined for human consumption. Thus, the maize supply chain in western Honduras is contaminated with mycotoxins at levels that pose health risks to both humans and livestock. More effective mycotoxin surveillance and implementation of effective mitigation strategies are needed to reduce mycotoxin contamination and exposure.

Effects of Harvest Time on Quality of Stored Maize (Zea mays L.) in the Southern Part of Ghana

In Ghana, most smallholder maize farmers delay harvesting of their crops in an attempt to achieve optimum moisture content levels necessary for safe storage. Late harvesting may cause a hike in insect attacks and fungal contaminations, leading to alterations in nutrient composition of grains. This study examined the effects of harvest time and storage form on quality of maize. Maize was grown and harvested from 36 plots, with each plot measuring 3m x 3m. Planting of maize was done during the major and minor seasons (April – August, 2020 and September – December, 2020) respectively. Moisture content of maize before storage was determined as 12.50 % to 12.85 % (major season) and 11.90 % to 12.48% (minor season). Harvesting was done at three stages (E = Early harvest, M = Mid harvest and L = Late harvest) and maize was stored for 90 days in three different ways (D = Dehusked, H = Husked and S = Shelled). Data was subjected to Analysis of variance (ANOVA) using Sisvar version 5.6. Mid harvest dehusked maize had the highest final starch content (69.28 %) while Early harvest husked maize had the highest protein content (7.22 %). Ash content of maize from the various treatments ranged from 3.50% to 5.39 % (initial) and 3.03 % to 4.13 % (final), the difference was significant (p&lt;0.05). Late harvest husked maize (LHH) recorded 35 % more initial ash as compared to EHS. Aflatoxin level was highest on Late harvest dehusked maize (60.70 ppb). Nutrient and aflatoxin levels of maize were significantly affected by harvest time. Encouraging farmers to adopt a better approach to harvesting, drying and storage of maize can reduce crop losses and ensure food security.

Individual and combined decontamination effect of fermentation and ultrasound on aflatoxin B1 in wheat-based doughs: a preliminary study

In this work, a preliminary investigation was conducted to examine the effect of ultrasound (US), alone or in combination with fermentation, on the reduction of aflatoxin B1 (AFB1) at 50 ng/g in wheat flour-based doughs. The US treatment was performed by soaking flasks containing triplicate samples of non-fermented and fermented (18 h at 28°C; 85% relative humidity) doughs in US bath (40 kHz; 100 W/cm2) at 35°C for 10, 30 and 60 min. Percentage reduction of AFB1 levels as determined by high-performance liquid chromatography varied between 3.6% and 46.0% in non-fermented doughs, and from 6.7% to 61.7% in fermented doughs. The US treatments used in the experiment did not interfere with the titratable acidity of fermented doughs, hence confirming US as a promising technique to reduce aflatoxin levels in fermented wheat-based products. The future studies are required to determine other parameters, such as temperature and pH of the product, to optimize the decontamination process of AFB1 as well as to evaluate possible effects of US on the sensory attributes of wheat-based products.

Correlation between Aspergillus flavus fungal biomass and aflatoxin contamination in harvested maize: insights from Kenya and Tanzania

Controlling the occurrence of aflatoxins in foods must be accompanied by managing the fungi responsible for their production. The abundance and diversity of aflatoxin-producing Aspergillus flavus are responsible for the accumulation of these toxins in crops, posing a persistent threat to public health and the economy in tropical developing countries. A study was conducted to investigate the occurrence and level of A. flavus and relate them to aflatoxin levels in maize in Kenya and Tanzania. A total of 786 maize samples were collected during harvesting in selected areas of the two countries for analysis. The fungal abundance in the samples was measured as the amount of fungal DNA relative to maize DNA. This was accomplished by quantifying the fungal DNA using qPCR, targeting the internal transcribed spacer (ITS) gene, while the maize DNA was quantified through the alpha-tubulin gene, the two genes known to be conserved. Aflatoxins were quantified using ultra-high performance liquid chromatography, coupled with ultra-high sensitivity, ultra-fast triple quadrupole tandem-mass spectrophotometer. A. flavus was detected in 88.5% of the 786 tested samples, and the average fungal load for these samples (expressed as the log host/pathogen ratio) was 5.53. Aflatoxin occurrence was positive in 31.9% of the samples, with an average level of 2.3 ± 0.643 ppb. The study established a positive relationship between the occurrence and level of aflatoxin B1 and the presence and biomass of A. flavus, which was statistically proven. These findings emphasize the need to place substantial attention on preharvest control of A. flavus in cereal fields as an effort to control the accumulation of aflatoxin B1 in foods.

Aflatoxins and Ochratoxin A in Tea Sold in Lebanon: Effects of Type, Packaging, and Origin.

Tea is among the oldest and most-known beverages around the world, and it has many flavors and types. Tea can be easily contaminated in any of its production steps, especially with mycotoxins that are produced particularly in humid and warm environments. This study aims to examine the level of ochratoxin A (OTA) and total aflatoxin (AF) contamination in black and green tea sold in Lebanon, evaluate its safety compared to international standards, and assess the effect of different variables on the levels of OTA and AFs. For this, the Lebanese market was screened and all tea brands (n = 37; 24 black and 13 green) were collected twice. The Enzyme-Linked Immunoassay (ELISA) method was used to determine OTA and AFs in the samples. AFs and OTA were detected in 28 (75.7%) and 31 (88.6%) samples, respectively. The average of AFs in the positive (above detection limit: 1.75 μg/kg) samples was 2.66 ± 0.15 μg/kg, while the average of OTA in the positive (above detection limit: 1.6 μg/kg) samples was 3.74 ± 0.72 μg/kg. The mean AFs in black and green tea were 2.65 ± 0.55 and 2.54 ± 0.40 μg/kg, respectively, while for OTA, the mean levels were 3.67 ± 0.96 and 3.46 ± 1.09 μg/kg in black and green tea samples, respectively. Four brands (10.8%) contained total aflatoxin levels above the EU limit (4 μg/kg). As for OTA, all samples had OTA levels below the Chinese limit (5 μg/kg). No significant association (p > 0.05) was found between OTA and tea type, level of packaging, country of origin, country of packing, and country of distribution. However, AF contamination was significantly (p < 0.05) higher in unpacked tea, and in brands where the country of origin, packing, and distributor was in Asia. The results showed that the tea brands in Lebanon are relatively safe in terms of AFs and OTA.