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Blanching of almonds was examined for reducing the aflatoxin content of contaminated nuts. Almonds with intact pellicles were spiked with aflatoxin B1 (AFB1) and blanched at 85°C. Following blanching, almond kernels and pellicles contained 20 and 19% of the spiked AFB1, respectively. The blanching water contained an additional 41% of the spiked AFB1. In a separate study, postblanching water was spiked with AFB1 and used for subsequent blanching of uncontaminated almonds. The resulting blanched kernels acquired 3.3% of the AFB1 from the spiked water, demonstrating a low level of cross-contamination from reused contaminated blanching water. The effect of the blanching temperature on partitioning of AFB1 from almonds to blanching water was significant at a 20-ppb spiking level, but not at 100 ppb. AFB1 levels that were unaccounted for in the mass balance of blanching components were presumed to be lost due to binding to water-solubilized almond components and were independent of pH and blanching time. Blanching reduced total aflatoxins in naturally contaminated almonds by 13 to 76%, depending on almond quality, as well as blanching time and temperature. These results indicate that the association between almond components and aflatoxin generated through mold contamination is more complex than in spiking experiments. HIGHLIGHTS

This study was conducted to determine the occurrence of 16 well-recognized and emerging mycotoxins in black and white sesame seed samples sold in Thailand and to evaluate possible health risks to consumers. Samples were extracted and cleaned with a modified QuEChERS procedure. Multiple mycotoxins in sesame seed samples were analyzed with a validated liquid chromatography-tandem mass spectrometry method. The risk of mycotoxin exposure via dietary intake of sesame seeds was evaluated based on the hazard quotient, margin of exposure (MOE), and quantitative liver cancer risk established by European Food Safety Authority, the Food and Agriculture Organization of the United Nations, and the World Health Organization. Of the 200 samples, 21.5% were contaminated with mycotoxins, 19.5% were contaminated with a single mycotoxin, and 2% were contaminated with multiple mycotoxins. Although 9% of total samples were contaminated with aflatoxins (AFs), only one black sesame seed sample and one white sesame seed sample were above the regulatory limits for the European Union (2 μg/kg). The MOE values derived from consumption of black and white sesame seeds were generally

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

Flax seed has become an increasingly popular food ingredient because of its nutrient richness as well as potential health benefits. Flax seeds are often ground before consumption, and flax seed cakes are used as animal feed. Aflatoxin production may occur subsequently when the ground seeds are stored in an environment that supports fungal growth. The objectives of this study were to determine the growth of two toxigenic fungi, Aspergillus flavus and A. parasiticus, and to quantify the concentrations of four major aflatoxins (AFB1, AFG1, AGB2, and AFG2) produced by the two fungi on ground flax seeds with water activities (aws) of 0.82, 0.86, 0.90, 0.94, and 0.98, incubated for 30 days at 20, 27, and 35°C. Results of the study showed that A. flavus was able to grow on ground seeds with aw from 0.86 to 0.98 at all three temperatures, and the most rapid growth occurred at aws 0.90 and 0.94 at 27°C. In comparison, A. parasiticus grew on seeds with aw from 0.86 to 0.98 at 27 and 35°C as well as on seeds with aw from 0.86 to 0.90 at 20°C, and the most favorable growth condition was aw from 0.90 to 0.94 at 35°C. A. flavus produced aflatoxins on seeds with aw from 0.90 to 0.94 at 27°C as well as on seeds with aw from 0.86 to 0.98 at 35°C, and the maximum total aflatoxin (298 μg/kg), AFB1 (247 μg/kg), and AFG1 (51 μg/kg) were found on seeds with aw 0.90 at 35°C. In comparison, A. parasiticus produced aflatoxins under a wider range of conditions, which included aw 0.86 at 27 and 35°C, aw 0.90 at 20 and 27°C, aw 0.94 at 27°C, and aw 0.98 at 35°C. The maximum total aflatoxin (364 μg/kg) and maximum AFB1 (324 μg/kg) along with 34 μg/kg AFG1 and 6 μg/kg AFB2 were produced by A. parasiticus on seeds with aw 0.98 incubated at 35°C for 30 days. Linear regression models also indicated that high incubation temperature (35°C) was optimal for overall fungal growth and for formation of high levels of aflatoxin by both fungi. Future studies should also address aflatoxin contamination in flax seed oil. HIGHLIGHTS

The antifungal and antiaflatoxigenic activity of Thymus vulgaris essential oil (EO) against Aspergillus flavus was evaluated over a range of concentrations in vapor- and liquid-phase contact tests. Total reduction in mycelial growth in the vapor- and liquid-phase tests was detected at EO concentrations of 20 and 400 μg/mL, respectively. Treatment with 10 μg/mL EO reduced aflatoxin production by 97.0 and 56.4% in the vapor- and liquid-phase tests, respectively. Greater inhibition of the expression of both fungal development-related genes (brlA, abaA, and wetA) and aflatoxin biosynthesis-related genes (aflR, aflD, and aflK) was also observed in the vapor-phase test. A substantial reduction in aflatoxin production was also observed in brown rice (72.7%) and white rice (18.0%). Our results indicate that the way this EO contacts fungal cells significantly affects its antifungal activity and that T. vulgaris EO in vapor phase might be a good strategy to control fungal contamination.

This meta-analysis was designed to review the published reports regarding the concentration and/or prevalence of aflatoxin M1 (AFM1) in human breast milk in Iran. The carcinogenic risk for Iranian infants consuming this milk was estimated with the hazard index. The PubMed and Scopus databases and the Scientific Information Database were screened for relevant studies between 1995 and 2017, and 11 of the 112 collected studies were included in the systematic review and meta-analysis. The mean (95% confidence interval) concentration of AFM1 was 5.85 ng/L (4.54 to 7.15 ng/L), which was lower than the European Union standard (25 ng/L). The mean prevalence of AFM1 in breast milk in Iran was 42% (11 to 77%). The estimated daily intakes for male and female infants were 0.02 to 5.57 ng/kg and 0.02 to 3.68 ng/kg of body weight per day, respectively. The rank order of estimated daily intake for both male and female infants according to age was 1 week > 1 month > 6 months > 12 months. The hazard index for all age groups of infants in all provinces in Iran was less than 1. Therefore, infants in Iran were not considered at carcinogenic risk from AFM1 in human breast milk.

The objective of this research was to apply near-infrared spectroscopy, with a short-wavelength range of 950 to 1,650 nm, for the rapid detection of aflatoxin B1 (AFB1) contamination in polished rice samples. Spectra were obtained by reflection mode for 105 rice samples: 90 samples naturally contaminated with AFB1 and 15 samples artificially contaminated with AFB1. Quantitative calibration models to detect AFB1 were developed using the original and pretreated absorbance spectra in conjunction with partial least squares regression with prediction testing and full cross-validation. The statistical model from the external validation process developed from the treated spectra (standard normal variate and detrending) was most accurate for prediction, with a correlation coefficient (r) of 0.952, a standard error of prediction of 3.362 μg/kg, and a bias of -0.778 μg/kg. The most predictive models according to full cross-validation were developed from the multiplicative scatter correction pretreated spectra (r = 0.967, root mean square error in cross-validation [RMSECV] = 2.689 μg/kg, bias = 0.015 μg/kg) and standard normal variate pretreated spectra (r = 0.966, RMSECV = 2.691 μg/kg, bias = 0.008 μg/kg). A classification-based partial least squares discriminant analysis model of AFB1 contamination classified the samples with 90% accuracy. The results indicate that the near-infrared spectroscopy technique is potentially useful for screening polished rice samples for AFB1 contamination.

HIGHLIGHTS The antifungal effect of the active substance in camellia seed cake is evaluated on Aspergillus flavus. The n-butanol phase exhibited an apparent antagonistic effect on A. flavus. A reference and a guide for natural antifungal agents is provided. Knowledge of the utilization of the by-products of camellia seed is broadened.

This study was carried out to evaluate the prevalence of mycobiota and aflatoxin (AF) B1 contamination in sesame seeds from rainfed and irrigated zones of the Punjab, Pakistan. For this purpose, 100 sesame seed samples were collected directly from the fields of major sesame-producing areas in rainfed and irrigated zones. The agar plate method was used for isolation of mycobiota, and thin-layer chromatography was used to determine AFB1 concentrations. Seed samples were then stored for 12 months. After 12 months, the seeds were again analyzed for mycobiota and AFB1 for comparison. All samples were positive for fungal growth under fresh and stored conditions. Twenty-one fungal species of 10 genera were isolated. Aspergillus flavus was the most prevalent contaminant found in fresh and stored sesame seeds from rainfed and irrigated zones, followed by Aspergillus niger, Alternaria alternata, and Fusarium oxysporum. The least prevalent fungi were Aspergillus ochraceus and Cladosporium oxysporum. Analysis revealed that 92% of fresh and 99% of stored seed samples were contaminated with AFB1. In the rainfed zone, 88% of fresh and 100% of stored seed samples were contaminated with AFB1, with mean concentrations of 15.74 and 33.8 ppb, respectively. In the irrigated zone, 96% of fresh and 98% of stored seed samples were contaminated with AFB1, with mean concentrations of 20.5 and 27.56 ppb, respectively. AFB1 concentrations >20 ppb were found in 20% of fresh and 100% of stored seeds samples from the rainfed zone and in 28% of fresh and 60% of stored samples from the irrigated zone and thus were not fit for human consumption as per the maximum limit (20 ppb) assigned by the U.S. Food and Drug Administration and the Food and Agriculture Organization of the United Nations. This report is the first on the mycobiota and AFB1 contamination in sesame seeds from rainfed and irrigated zones of the Punjab, Pakistan. These baseline data are an initial step in the effort to deal with this significant food safety issue. HIGHLIGHTS

Almonds rejected as inedible are often used for production of almond oil. However, low-quality almonds are frequently contaminated with aflatoxins, and little is known regarding transfer of aflatoxins to almond oil during processing. In this study, oil was produced from reject almonds by hexane extraction. Of 19 almond samples that were naturally contaminated with aflatoxins, 17 oil samples contained measurable amounts of aflatoxins, and aflatoxin content of contaminated oil was correlated with aflatoxin content of the nuts. However, oil aflatoxin levels were not correlated with the oxidation level of the oil as measured by percent free fatty acids and peroxide value. Adsorbents used in oil refining were tested for their ability to remove aflatoxins from contaminated oil. Fuller's earth and bentonite were the most effective, removing 96 and 86% of total aflatoxins from contaminated oil samples, respectively. Treatment with diatomaceous earth, in contrast, had no effect on aflatoxin levels in oil. These results show that oil refining steps using mineral clay adsorbents may also function to remove aflatoxins from contaminated oil. HIGHLIGHTS

The objective of this study was to investigate the occurrence of aflatoxin M1 (AFM1) in Chinese liquid milk products. A total of 190 liquid milk samples, including 168 ultrahigh-temperature-treated milk samples and 22 pasteurized milk (PM) samples, were collected in August 2019. A screening assay with the Charm rapid test kit and a confirmation method with high-performance liquid chromatography were used for AFM1 analysis. Nine (4.74%) samples were screened positive, of which 5 (2.11%) samples were confirmed with concentration levels of 0.022 to 0.049 μg/kg. The AFM1 levels confirmed were all below the maximum residue levels set by China, the European Union, the United States, and the Codex Alimentarius Commission. The detection rate of AFM1 in domestic milk samples was 3.39%, while no AFM1 was detected in samples of imported milk. The prevalences of AFM1 detected in three groups of brands were as follows: group I, the major brands of China, 2.70%; group II, the local city domestic brands, 4.55%; and group III, the brands imported into China, 0. The detection rate of AFM1 was significantly higher in PM samples (9.09%) than in ultrahigh-temperature-treated samples (1.19%) (P < 0.05). Although the residue level of AFM1 did not exceed the maximum residue levels in any of the samples, the higher detection rate in local Chinese brands, especially in PM samples, deserves the attention of the Chinese government and consumers. HIGHLIGHTS

The aim of the study was to determine the levels of aflatoxin B1 (AFB1) and ochratoxin A (OTA) in durum wheat samples collected over six periods of time from two official warehouses (A and B) in Lebanon. The concentrations of AFB1 in wheat samples taken from both warehouses ranged from 1.05 to 7.36 μg/kg. Results showed that 23.3 and 25.3% of samples taken from warehouse A and warehouse B, respectively, had AFB1 levels >2 μg/kg. For OTA, the contamination level of wheat samples taken from warehouse A and warehouse B was 52.0 and 44.6%, respectively, with concentrations ranging from 0.51 to 9.71 μg/kg. The percentage of samples with high detectable OTA levels (>3 μg/kg) was 28.6 and 25.3% for wheat samples taken from warehouse A and warehouse B, respectively. Thus, the consumption of wheat and derived products in Lebanon can be considered hazardous and may present a significant risk to the health of the Lebanese population regarding the overall daily exposure to these mycotoxins. HIGHLIGHTS

Texas A&M AgriLife Research (hereafter AgriLife) introduced a quality systems approach to accurately measure and manage aflatoxin that resulted in improved food safety for approximately 10 million Kenyans. A quality systems approach contains elements that ensure laboratory testing competence. In this study, quality system elements included analyst training and qualification, proficiency testing, use of reference material to support analytical traceability and define analytical uncertainty, development and implementation of a food safety plan by commercial maize (Zea mays) millers, and verification of testing accuracy at the AgriLife laboratory accredited by the Kenya Accreditation Service under the International Organization for Standardization/International Electrotechnical Commission 17025:2005 standard. In 2014 and 2015, five proficiency rounds were performed, ranging in aflatoxin concentrations of 5 to 40 μg/kg. Five laboratories had a z-score of >3, and all of these were for the fifth proficiency round with an aflatoxin content of 5 μg/kg. In 2015, 31 analysts qualified to participate in the program at 15 maize mills. The analysts' qualification for seven test samples, which ranged from 3.1 to 28 μg/kg total aflatoxin, resulted in an average relative standard deviation of 19.2% across all participants and test methods. Independent testing of participating mill verification results before and after analyst implementation of the quality systems approach revealed an improvement in measure accuracy.

Maize ( Zea mays) is a staple in many developing countries but is known to be prone to pest (insects, birds, and rodents) and fungal infestation. In Guatemala, mycotoxin contamination of cultivated products may occur owing to such factors as environmental conditions and the use of traditional agriculture operations. To assess the current maize conditions in Guatemala, a small-scale study was performed. Mold and insect counts and mycotoxin (aflatoxin and fumonisin) concentrations were determined on 25 farms in two townships (Chiantla and Todos Santos) of the Huehuetenango Department. Total fungal counts were 3.6 to 6.83 log CFU/g with no significant differences ( P > 0.05) across farms at different altitudes. Farms where maize was not produced but was purchased were at higher risk of fumonisin contamination, whereas local producers were mostly affected by aflatoxins. Aflatoxin was present in maize from 100% of farms at 1.0 to 85.3 ppb, and fumonisin was detected on 52% of farms at 0.4 to 31.0 ppm. Average mycotoxin consumption amounts were above the recommended maximum intake for aflatoxin in both produced and purchased maize and above the provisional maximum tolerable daily intake for fumonisin in purchased maize. Estimated daily intake was 0.01 to 0.85 μg/kg of body weight per day for aflatoxin and 2.9 to 310.0 μg/kg of body weight per day for fumonisin. An entomological analysis revealed overall 32% prevalence of Ephestia kuehniella (flour moth), 16% prevalence of Sitophilus zeamais (maize weevil), and 8% prevalence of Tribolium sp. (flour beetle) on the analyzed farms. This study highlighted poor agricultural practices used in the highlands of Guatemala. Current practices should be revised for the production of maize that is safe for consumption by the population in this region.

Herbs derived from roots, leaves, flowers, or fruits of plants are unavoidably contaminated with fungi and mycotoxins during growth, harvest, and storage, thereby posing a health threat to humans. Especially, root herbs (RHs) are more easily contaminated with fungi and mycotoxins because the roots are in direct contact with the soil. Here, we investigated the occurrence of fungi, aflatoxins (AFs), and ochratoxin A (OTA) in eight RHs that are used as medicines, beverages, dietary supplements, and functional foods in China and other countries. Morphological observation and MultiGeneBlast (β-tubulin and calmodulin) were used to identify the potentially toxigenic fungi. Of the 48 samples tested, all were contaminated by fungi, and 1,844 isolates belonging to 25 genera were detected. The genera Aspergillus and Penicillium, which contain potentially toxigenic fungal species, represented a frequency of 10 and 25%, respectively. Thirty-three isolates of Aspergillus flavus, Aspergillus parasiticus, Aspergillus niger, and Penicillium polonicum were arbitrarily selected for analysis of their toxigenic potential. Five of 13 isolates of A. flavus and 1 isolate of A. parasiticus produced AFs, whereas OTA production was not detected for any of the isolates of A. niger and P. polonicum. The occurrence of AFs and OTA in the 48 samples of eight RHs was tested by ultraperformance liquid chromatography-tandem mass spectrometry; 37.50% of samples from six RHs were contaminated with AFs and 16.67% of samples from four RHs were contaminated with OTA. Seven (14.58%) and four (8.33%) samples of ginseng, polygala, and liquorice exceeded the permissible limits of aflatoxin B1 and AFs, respectively. Because ginseng, polygala, and liquorice are widely used as herbs, dietary supplements, and functional foods, the high frequency of AF contamination of these herbs indicated by our current study warrant attention to raise public awareness.

The aim of this study was to evaluate the ability of heat-killed baker's yeast (HKBY), the cell wall of baker's yeast (CWBY), and cell wall (1→3)-β-d-glucan of baker's yeast (BGBY) to bind aflatoxin B1 (AFB1) in phosphate-buffered saline (PBS) spiked with 0.5 μg/mL AFB1. Baker's yeast ( Saccharomyces cerevisiae) was heat killed by autoclaving at 121°C for 10 min. The cell wall was physically extracted, and (1→3)-β-d-glucan was extracted by a modified method. The concentration of AFB1 was determined by high-performance liquid chromatography after exposure to binders for three contact times, 30 min, 5 h, and 24 h, at room temperature. AFB1 binding by HKBY, CWBY, and BGBY was 6.30 to 46.34%. The lowest binding capacity was found for HKBY with a contact time of 30 min, and the highest binding capacity was found for BGBY with a contact time of 24 h. Among binders, CWBY had the highest binder-AFB1 complex stability during washing with PBS, and the lowest stability was found for HKBY complexes. Results of this study indicated that BGBY was the most effective binder, and more exposure to BGBY removes more AFB1 from PBS.

Recently, cultivation of high-yielding hybrid maize varieties has revolutionized maize production in Pakistan. Analyses of nutritional traits and aflatoxin (AF) contamination in these varieties can aid in the identification of susceptible and resistant varieties, particularly for cultivation in the Pakistani agro-climatic environment. Five spring maize varieties-Pioneer, Neelam, DK-919, Desi, and Hi-maize-were selected for analyses of their nutritional, tocopherol, and AF contents. Protein, carbohydrate, oil, ash, fiber, and moisture contents ranged between 8.7 and 10.8%, 68 and 71%, 3.72 and 5.56%, 1.09 and 1.81%, 1.1 and 3.1%, and 11.7 and 14.2%, respectively. Tocopherol levels in selected varieties were in the range of 461 to 1,430 μg/g. Hi-maize exhibited significantly higher protein and tocopherol contents than the other varieties, indicating its better suitability for feed and silage applications. The highest mean level of total AFs, 14.5 ± 0.12 μg/kg, was found in Desi, and results showed that the most dominant AF found in the maize varieties was AFB1. Furthermore, the results showed that the higher the level of tocopherol, the lower the concentration of total AFs and vice versa in maize varieties. The results can be used to investigate additional susceptible maize varieties that are resistant to fungal attack.

Aflatoxin B1 (AFB1) is the most potent of the dietary aflatoxins, and its major metabolite, aflatoxin M1 (AFM1), is frequently found in the breast milk of lactating mothers. The aim of this study was to assess the occurrence and factors associated with AFM1 contamination of breast milk collected from lactating mothers in Lebanon. A total of 111 breast milk samples were collected according to the guidelines set by the World Health Organization. Samples were analyzed with a competitive enzyme-linked immunosorbent assay between December 2015 and November 2016. A survey was used to determine the demographic and anthropometric characteristics of participating lactating mothers. Dietary habits were assessed using a semiquantitative food frequency questionnaire. Mean (±standard deviation) concentration of AFM1 in the breast milk samples was 4.31 ± 1.8 ng/L, and 93.8% of samples contained AFM1 at 0.2 to 7.9 ng/L. The mean concentration of AFM1 was significantly lower (P 0.05) was observed between AFM1 concentrations in breast milk and anthropometric sociodemographic factors (age and level of education) or the governorate of residence of the nursing mothers. The mean AFM1 estimated daily intake was found to be 0.69 ng/day/kg of body weight. Although the incidence of AFM1 contamination was low, our first-of-its-kind study highlights the importance of conducting investigations on mycotoxin contamination in breast milk and of developing protection strategies to tackle the exposure of infants to this potent chemical hazard.

In this study, we aimed to establish a method for determination of multiple mycotoxins such as aflatoxins, ochratoxin A, and zearalenone in red pepper powder samples based on the quick, easy, cheap, effective, rugged, and safe (QuEChERS) approach for extraction and cleanup, with detection and quantification by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) in both positive- and negative-ion modes. The developed LC-MS/MS analytical method was compared with an enzyme-linked immunosorbent assay (ELISA) to improve the reliability of our developed method. The linearity, precision, and accuracy were validated for the LC-MS/MS methods. The results obtained with the LC-MS/MS were linear, with a correlation coefficient (R2) of >0.998. The limits of detection and quantification for mycotoxins were 0.07 to 0.71 μg/kg and 0.20 to 1.81 μg/kg, respectively. Intra- and interday precision tests (expressed as the relative standard deviation) for each analyte were 1.58 to 5.97% and 0.97 to 9.01%, respectively. Average recoveries were 85.70 to 94.99%. The validation results for the ELISA were linear (R2 > 0.995), and recoveries were 77.13 to 93.93%. Both analytical methods were applied to determine the presence of mycotoxins in commercial red pepper powder samples from South Korea. Four of the total 56 samples were contaminated with aflatoxins, and 6 samples were contaminated with ochratoxin A; these results were consistent for the two methods (P > 0.05). Therefore, our developed LC-MS/MS with QuEChERS approach for determination of multiple mycotoxins may be useful for controlling the quality and safety of red pepper powder.

Subsistence farming and poor storage facilities favor toxigenic fungal contamination and mycotoxin accumulation in staple foods from tropical countries such as Haiti. The present preliminary study was designed to evaluate the occurrence of toxigenic fungi in Haitian foodstuffs to define the mycotoxin risk associated with Haitian crops. The objectives of this research were to determine the distribution of toxigenic fungi in the Haitian crops maize, moringa, and peanut seeds and to screen Aspergillus section Flavi (ASF) isolates for production of aflatoxins B1 and G1 in vitro. Maize, moringa, and peanut samples were contaminated by potential toxigenic fungal taxa, mainly ASF and Fusarium spp. The isolation frequency of Aspergillus spp. and Fusarium spp. was influenced by locality and thus by farming systems, storage systems, and weather conditions. Particularly for ASF in peanut and maize samples, isolation frequencies were directly related to the growing season length. The present study represents the first report of contamination by toxigenic fungi and aflatoxin in moringa seeds, posing concerns about the safety of these seeds, which people in Haiti commonly consume. Most (80%) of the Haitian ASF strains were capable of producing aflatoxins, indicating that Haitian conditions clearly favor the colonization of toxigenic ASF strains over atoxigenic strains. ASF strains producing both aflatoxins B1 and G1 were found. Understanding the distribution of toxigenic ASF in Haitian crops and foodstuffs is important for determining accurate toxicological risks because the toxic profile of ASF is species specific. The occurrence of toxigenic fungi and the profiles of the ASF found in various crops highlight the need to prevent formation of aflatoxins in Haitian crops. This study provides relevant preliminary baseline data for guiding the development of legislation regulating the quality and safety of crops in this low-income country.

This study presents the assessment of total aflatoxins (TAFs) in basmati rice (brown, 1,081; white, 1,170) collected from different areas of Punjab, Pakistan, during 2010 to 2015. Due to the carcinogenicity of TAFs, daily dietary exposure is also evaluated based on rice consumption survey data. Methodology was standardized by matrix spike recoveries at four fortification levels (0.1, 0.5, 2.5, and 12.5 ng/g) for TAFs (aflatoxins B1 [AFB1], B2 [AFB2], G1 [AFG1], and G2 [AFG2]). The present study reveals that 1,750 samples (77.74%) were tainted with AFB1, whereas TAFs were detected in 370 samples (16.43%). Of positive samples, 854 brown rice samples (79%) were positive for AFB1, and 154 samples (14.24%) were contaminated with TAFs. For white rice, 896 samples (76.58%) were contaminated with AFB1, whereas 205 samples (18.46%) were found positive for TAFs. Study findings were used to construct a frequency distribution, and AFB1 levels were also compared against permissible levels of TAFs (10 ng/g) as...

The food additives sodium bisulfite, sodium hypochlorite, citric acid, and ammonium persulfate were evaluated for their effectiveness in degrading aflatoxin in samples of distillers wet grains (DWG) and condensed distillers solubles (CDS) obtained from an industrial ethanol plant. Aqueous food additive solutions, 0.5% by weight, were added to DWG or CDS at the level of 0.5 ml/g of sample, and the materials were heated at 90°C for 1 h. Sodium bisulfite was not effective in degrading aflatoxin in either DWG or CDS. Among the four food additives tested, sodium hypochlorite was the most effective. However, it bleached the substrate and left an off-odor. Citric acid and ammonium persulfate reduced aflatoxin levels by 31 to 51%. Citric acid is the most promising additive for degrading aflatoxin because it has been classified as generally recognized as safe by the U.S. Food and Drug Administration. Aflatoxin reduction was enhanced by increasing the citric acid addition level and prolonging the heating time. Reductions of 65 and 80% in DWG and CDS, respectively, were obtained by the addition of 2.5% (by weight) citric acid and heating at 90°C for 1 h. Aflatoxin levels in DWG and CDS were gradually reduced with prolonged heating at 90°C, even without the addition of food additives. Aflatoxin reductions of 53 and 73% were achieved in DWG and CDS as a result of heating at 90°C for 5 h.

Experiments were conducted to assess the influence of storage practices on mycotoxin incidences in stored maize and groundnuts in Kilosa District, Eastern Central Tanzania. Factorial experiments were used to test the effects of processing, storage conditions, and protectants at 3-month intervals for 12 weeks. Temperature and relative humidity data were recorded by using data loggers. The differences among the treatment means were compared using Tukey's honestly significant difference test at 5% probability level. The log-linear model was used to determine the influence of weather on mycotoxin. Dried neem (Azadirachta indica) leaves significantly reduced fumonisin B1 (FB1) in stored maize. Levels of FB1 were significantly higher in maize heaped on the floor than in the other tested storage methods (P < 0.001). Similarly, aflatoxin levels were significantly higher in groundnuts stored in nylon bags than in the other tested methods (P < 0.001). The high concentration of mycotoxins at the study villa...

We combined immunoaffinity column (IAC) and enzyme-linked immunosorbent assay (ELISA) methods to develop a rapid method to analyze total aflatoxin (AF) in foods, using a large number of samples. Using newly developed monoclonal antibodies, with high cross-reactivity and high organic solvent tolerance, we developed the IAC-ELISA method. Our IAC-ELISA method showed a good correlation with the high-performance liquid chromatography method for corn samples spiked with total AF. Certain food samples, such as chili powder, chocolate, green coffee beans, and roasted coffee beans, are difficult to measure owing to their matrices, which affect ELISA adversely. Our IAC-ELISA method clearly improved the recovery rates (79 to 109%) compared with the ELISA method (97 to 164%) for four food samples. Our method is simple and quick; thus, it may be ideal for routine inspections.

This study was conducted to investigate possible contamination by aflatoxins (AFs) and aflatoxigenic fungi in imported chia seeds consumed in Thailand. A survey was performed on 100 samples of imported chia seeds collected from supermarkets and health food stores in Bangkok from May 2017 to February 2018. Ten mold species belonging to Aspergillus and Penicillium were isolated, and Aspergillus flavus was the most prevalent aflatoxigenic fungi. Chia seed samples were cleaned with an immunoaffinity column and analyzed for AFs by high-performance liquid chromatography with fluorescence detection using precolumn derivatization. AFs were detected in 40% of total samples at concentrations of 0.4 to 10.99 ng/g. Among the positive samples, three were contaminated with total AFs at concentrations higher than the European Union regulatory limit (4 ng/g). The most commonly found AF found in chia seeds was AFB1. HIGHLIGHTS

An enzyme-linked immunosorbent assay (ELISA) was established for the specific detection of Aspergillus parasiticus and Aspergillus flavus. A New Zealand white rabbit was immunized intravenously with 100 μg of A. parasiticus CCRC 30117 mycelial protein extracts. The antibodies were separated and purified. The optimal concentration of the antibody and antibody-peroxidase conjugate used in the established ELISA was 10 μg/ml with a detection limit of 1 μg/ml. Among the 126 strains tested (including 21 strains of A. parasiticus, 11 strains of A. flavus, 34 isolates of A. parasiticus/A. flavus from cereals, and 60 strains of non-A. parasiticus/A. flavus fungi), the false-negative and false-positive rates were 1.5 and 3.3%, respectively. Strains of Aspergillus flavofrucatis and Aspergillus sojae produced false-positive reactions. However, their antigens had much lower cross-reactivity with the antibodies raised against A. parasiticus, as shown from I50 values. The molecular weights of the main antigens of A. par...

Molds were isolated from various foods from Burundi and identified. The ability of these molds to produce aflatoxins, cyclopiazonic acid (CPA), and fumonisins, and the presence of these toxins in the foods were determined. Fusarium moniliforme was the predominant mold isolated from corn. It was also one of the dominant molds isolated from sorghum and sorghum meal. Very few molds were isolated from polished rice, millet, and millet meal. F. semitectum and F. equiseti were the most common molds isolated from haricot and mung beans. F. semitectum was also the predominant mold in peanuts. Peas ( Pisum sativum ) were predominantly contaminated with Aspergillus ochraceus and A. wentii . The predominant molds isolated from dried nonsalted Ndagala fish ( Limnothrissa miodon and Stolothrissa tanganicae ) were A. flavus , A. niger and A. sydowi . Dried crushed cassava ( Manihot esculenta ) tubers and cassava flour were predominantly contaminated with Penicillium citrinum , P. corylophilum , and P. chrysogenum . Very few molds were isolated from the infant food Musalac™. Thirty-seven of 95 isolates of A. flavus and all 5 isolates of A. parasiticus produced aflatoxins. Sixty-seven of the 95 isolates of A. flavus produced CPA, and all aflatoxin-producing A. flavus produced CPA. Ten of 20 isolates of A. oryzae and A. tamarii produced CPA. Fifty-one of 56 isolates of F. moniliforme and all 4 isolates of F. proliferatum produced fumonisins. High levels of fumonisin B1 (12.2 to 75.2 μg/g) were detected in all 6 samples of corn and 1 sample of sorghum meal. Neither aflatoxins nor CPA were found in any of the foods.

Aspergillus flavus and the closely related subspecies parasiticus have long been recognized as major contaminants of organic and nonorganic items. A. flavus , a common soil fungus, can infest a wide range of agricultural products. Some A. flavus varieties produce aflatoxins, which are carcinogenic toxins that induce liver cancer in laboratory animals. A. flavus var. flavus , A. flavus subsp. parasiticus , and A. nomius share the ability to produce aflatoxins. Identification of the A. flavus species group is mainly based on the color and macroscopic and microscopic characteristics of the fungus. A. flavus growth and aflatoxin biosynthesis depend on substrate, moisture, temperature, pH, aeration, and competing microflora. The growth of A. flavus and aflatoxin production are sometimes unavoidable. Aflatoxins are considered natural contaminants; the ideal control approach is prevention of mold growth and aflatoxin production. The detection of members of the A. flavus species group in foods and feed is generally carried out by using plate techniques such as surface spread or direct plating. Research on alternative fungal detection methods is still in its infancy. Few immunoassay techniques have been investigated in this regard. Aflatoxins are generally analyzed by chemical methods, although immunochemical methods which use antibodies are becoming common analytical tools for aflatoxins.

Mycotoxins comprise a family of fungal toxins, many of which have been implicated as chemical progenitors of toxicity in man and animals. The most thoroughly studied are the aflatoxins. A variety of physical, chemical, and biological methods to counteract the mycotoxin problem have been reported, but large-scale, practical, and cost-effective methods for detoxifying mycotoxin-containing feedstuffs are currently not available. The most recent approach to the problem has been the addition to the animal's diet of nonnutritive sorbents that sequester mycotoxins and reduce their gastrointestinal absorption, avoiding their toxic effects on livestock and toxin carryover into animal products. This review comments on the in vitro efficacy of several of the adsorbents assayed, and their in vivo applications in a range of animals will be discussed. The sorbents reviewed are activated charcoal, bentonite, zeolite, hydrated sodium calcium aluminosilicate (HSCAS) and a wide variety of clays and synthetic ion-exchange resins.

Mold growth, sporulation, and aflatoxin B 1 and G 1 production were studied in Sabouraud dextrose agar (SDA) and frankfurters inoculated with Aspergillus flavus or Aspergillus parasiticus. Each of four phosphates, sodium polyphosphate glassy (SPG), sodium acid pyrophosphate (SAPP), tetrasodium pyrophosphate (TSPP), and Brifisol 414 (a blend of SPG, SAPP, and TSPP) were incorporated into the SDA (1 or 2%) or used as dipping solutions (5%) for the frankfurters. In SDA at 30°C, significant (P < 0.05) reductions in aflatoxin B 1 and G 1 production by A. flavus and A. parasiticus occurred when 1% SPG, 1% TSPP, 1% Brifisol 414, and 2% SAPP were present. In frankfurters, A. flavus B 1 aflatoxin production was increased with SAPP and TSPP.

Production of aflatoxins, sterigmatocystin, citrinin, and ochratoxin A by Aspergillus and Penicillium species on agar in 50-ml flasks after 21 days was detected and confirmed by thin-layer chromatography. Toxins were extracted with 2.5 ml of acidified methylene chloride for 20 to 60 min. Mycotoxin concentrations were estimated by liquid chromatography. Addition of formic acid to the methylene chloride extraction solvent effected an increase in recovery of ochratoxin A from Czapek-yeast (CY) agar from 20% to 91%. Recoveries of added mycotoxins were generally higher from CY agar than from yeast extract-sucrose (YES) agar and ranged from 11% (citrinin from YES agar) to 91% (ochratoxin A from CY agar). The method described is convenient, rapid, and reproducible, since it samples the entire culture surface. Human exposure to volatile solvents is also minimized.

Lactic acid bacteria are extensively used in the fermentation of a wide variety of food products and are known for their preservative and therapeutic effects. Many lactic acid bacteria species have been reported to inactivate bacterial pathogens, and numerous antibacterial substances have been isolated. However, the antimycotic and antimycotoxigenic potential of lactic acid bacteria has still not been fully investigated. Fermented foods such as cheese can be contaminated by molds and mycotoxins. Mold causes spoilage and renders the product unusable for consumption, and the presence of mycotoxins presents a potential health hazard. A limited number of reports have shown that lactic acid bacteria affect mold growth and aflatoxin production. Although numerous lactic acid bacteria such as Lactobacillus spp. were found to inhibit aflatoxin biosynthesis, other lactic bacteria such as Lactococcus lactis were found to stimulate aflatoxin production. The morphology of lactic acid bacteria cells has also been found to be affected by the presence of fungal mycelia and aflatoxin. Lactococcus lactis cells became larger and formed long chains in the presence of Aspergillus flavus and aflatoxins. Numerous investigations reported that low pH, depletion of nutrients, and microbial competition do not explain the reason for aflatoxin inhibition. Some investigators suggested that the inhibition of aflatoxin is due to lactic acid and/or lactic acid bacteria metabolites. These metabolites have been reported to be heat-stable low-molecular-weight compounds.

A mixture of Lactobacillus species from a commercial silage inoculum reduced mold growth and inhibited aflatoxin production by Aspergillus flavus subsp. parasiticus . Actively growing Lactobacillus spp. cells totally inhibited germination of mold spores. Culture supernatant broth from the mixture of strains inhibited mold growth but did not destroy mold spore viability. Some mold spores were observed microscopically to have germinated and produced short nonbranching germ tubes; then growth ceased. While the pH of the culture broth and supernatant were about 4.0, acidification of nonfermented broth to pH 4.0 with HCl and lactic acid did not cause a similar inhibition of spore germination. The mixture of Lactobacillus species growing in a dialysis sack inhibited aflatoxin production by the A. flavus culture growing outside of the sack in broth, whereas mold growth was not affected. The pH values outside of the dialysis sack in the control and the treatments were similar (6 to 7) throughout the incubation period. When a dialysis sack with a molecular weight cutoff (MWCO) of 1,000 was used, there was little inhibition of aflatoxin B1 production, but with MWCOs of 6,000 to 8,000 and 12,000 to 14,000 aflatoxin production was greatly inhibited. In mixed culture experiments, levels of aflatoxin B1 and G1 were depressed compared to the control (monoculture). Mold growth in this case was also reduced compared to the monoculture system. Purified isolates of Lactobacillus from the commercial mixture had a slight effect on mold growth and aflatoxin production, but supernatant liquid of one isolate was quite inhibitory to production of aflatoxins B1 and G1, without affecting mold growth.

Mycelial growth of Aspergillus parasiticus NRRL 2667 and aflatoxin production on Florunner peanuts grown under different calcium supplementation levels (CSL) (550, 1,100, 2,200 and 4,400 kg gypsum/ha) with initial spore loads of 102, 104 and 106 spores/g were investigated. Growth at 25°C for 0, 4, 7 and 14 days was determined by viable plate counts on Aspergillus flavus/parasiticus agar (AFPA) medium. Irrespective of the initial spore load, maximum growth of 108 to 109 CFU/g was attained after 14 days except for the 4,400 kg/ha Ca-supplemented nuts on which the maximum populations were one log less. Aflatoxins B1 and G1 concentrations measured by thin layer chromatography (TLC) ranged from 0-3460 (μg/g and 0-3740 (μg/g, respectively. Toxin production was highest in single peanuts with CSL of 2,200 kg/ha. A reduction of 50% or higher was observed as CSL was increased to 4,400 kg/ha.

An improved disc diffusion type bioassay was developed for T-2 toxin (T-2), HT-2 toxin (HT-2), diacetoxyscirpenol (DAS), deoxynivalenol (DON), nivalenol (NIV), neosolaniol (NSL), fusarenon-X (FUS-X), trichothecin (TIN), roridin A (RDA) and verrucarin A (VCA) using the yeast, Kluyveromyces marxianus . Factors such as type of medium, agar volume per plate, preincubation time and temperature, incubation temperature, inoculum size and pH had variable, and in some cases a dramatic effect on the sensitivity of the assay. The effect of pH of the assay medium was particularly pronounced. The highest sensitivity was obtained when 6 ml per plate of a tryptic-soy-agar (TSA) medium (pH 7.5) containing 105 CFU inoculum per ml was incubated at 38°C for 18 h. All of the trichothecenes (TNN) were able to inhibit the growth of the yeast with the detection limit being 0.005, 0.01, 0.02, 0.02, 0.1, 0.5, 10, 10, 10 and 50 μg/disc for VCA, RDA, T-2, TTN, DAS, HT-2, DON, NSL, FUS-X and NIV, respectively. The detection limits for corn and wheat spiked with T-2 were 0.1 and 0.2 μg/g, respectively. Non-TNN mycotoxins that did not inhibit yeast at a concentration of 200 μg/disc were aflatoxin B1 (AFB1), ochratoxin A (OA), citrinin (CT), penicillic acid (PA), cyclopiazonic acid (CPA), penitrem-A (PTA) and zearalenone (ZEE). These results indicate that disc diffusion assay using K. marxianus under optimized conditions provides a sensitive method for the detection of low concentrations of several TNN.

The antimutagenic effects of various tea extracts prepared from nonfermented tea (green tea), semifermented tea (oolong tea and pouchong tea), and fermented tea (black tea) were investigated by Salmonella/microsome assay. No mutagenicity or toxicity in Salmonella typhimurium TA98 and TA100 was observed with any tea extract. The tea extracts markedly inhibited the mutagenicity of 2-amino-3-methylimidazo(4,5-f)quinoline, 3-amino-1,4-dimethyl-5H-pyridol(4,3-b)indole,2-amino-6-methyldipyrido(l,2-a:3',2'-d)imidazole, benzo[a]pyrene, and aflatoxin B1 toward S. typhimurium TA98 and TA100 in the presence of S9 mixture, especially those of oolong and pouchong teas inhibited over 90% mutagenicity of these five mutagens at the dosage of 1 mg per plate. Among four tea extracts, black tea exhibited the weakest inhibitory effect on mutagenicity of these five mutagens. The mutagenicity of 4-nitroquinoline-N-oxide, a direct mutagen, was not inhibited by black and oolong tea extracts to S. typhimurium TA98 in the absence of S9 mixture but was increased by the tea extracts at the dose of 1 mg per plate to S. typhimurium TA100. As the antimutagenic effect of semifermented tea was stronger than nonfermented and fermented teas, some antimutagenic substances might be formed during manufacturing processes of tea.

Lactic acid bacteria from "Idly", a traditional cereal pulse product of southern India, were evaluated for antimutagenic properties. Effect of their presence in Salmonella mutagenicity assay with foodborne mutagens like spice extracts, amino acid pyrolysates, and aflatoxins was examined. Variation of antimutagenic potential at different growth stages of these lactic acid bacteria was examined in time-course studies. The enzyme profile was examined to determine any possible relationship between antimutagenicity and enzymes in these lactic acid bacteria. Most of the lactic acid bacteria tested were found to decrease mutagenicities exerted by these mutagens significantly. Time-course studies showed that antimutagenic ability decreased in stationary phase of growth of lactic acid bacteria. There was no correlation between antimutagenicity and enzyme profile quantifying proteolytic, lipolytic, and other enzymes of carbohydrate metabolism. Lactic acid bacteria from "Idly" were found to be effective in suppressing the mutagenicities of the kinds encountered in foods.

The mycoflora of 69 samples of animal mixed feeds were studied. Fungal counts ranged from 102 to 108 CFU/g, the lowest counts corresponding to the samples of rabbit feeds. Seventy-one fungal species belonging to 26 genera were identified. The pre- dominant species were Aspergillus flavus , Fusarium moniliforme , and Penicillium chrysogenum . Thirty-six strains of A. flavus and one strain of A. parasiticus were screened for aflatoxin production in yeast extract-sucrose medium. The final pH, weight of mycelium, and production of aflatoxins were determined after 14 days of incubation. Five strains (13.5%) were aflatoxigenic. No statistical differences were observed in mycelial dry weights and final pH between aflatoxin-producing strains and nonaflatoxigenic strains.

Blends (0:1, 1:3, 1:1, and 3:1, wt/wt) of aflatoxin-contaminated and sound peanut kernels were submerged for 1, 2, and 3 min in various concentrations of hydrogen peroxide solution. The effectiveness of these treatments in separating aflatoxin-contaminated kernels from sound kernels was determined. Peanuts that floated (floaters) and those that did not (sinkers) were subjected to aflatoxin analysis. Second order polynomial equations were satisfactorily fitted to the experimental data. Hydrogen peroxide concentrations of 0.075, 0.150, and 0.25% resulted in a reduction in aflatoxin content in the kernels in the sinker fraction by 90% within 1 min, regardless of the initial aflatoxin content. The total aflatoxin content in sinker and floater fractions was approximately the same as that in unfractionated samples, indicating that the low concentrations of hydrogen peroxide in treatment solutions did not degrade aflatoxin. Response surface methodology was used to generate contour plots which revealed optimum treatment conditions for giving a maximum yield of the sinker fraction with low aflatoxin content. For peanuts containing 50 ppb aflatoxin, optimum conditions consist of a 0.08% hydrogen peroxide treatment for 0.7 min. This procedure results in a maximum sinker fraction yield of 85.5% of the original lot with a residual aflatoxin content of ≤5 ppb.

A model is presented which integrates literature data on the effects of temperature, water activity, pH, and colony size on mold growth and aflatoxin formation. Mathematical forms for the rates of growth and toxin formation are based on assumptions about the biology of toxigenesis. The rate of toxin formation is assumed to be proportional to the rate of production of new cell mass, and the rate of toxin degradation is assumed to be proportional to the product of the concentrations of dead cell mass and aflatoxin; the latter assumption is an attempt to be consistent with the notion that toxin degradation is effected by enzymes released during mycelial lysis. Growth rate and toxin yield are represented by a maximum or reference value times a series of factors dependent on environmental conditions. Temperature and water activity have an interactive effect on growth and toxigenesis in the model. An Arrhenius-like function is postulated for the effects of temperature; shape parameters in the function are selected assuming that optimum temperature bears a fixed relationship to temperature limits for growth and toxigenesis, which vary with water activity. A linear function is postulated for the effect of water activity, with the lower limit dependent on temperature. Parabolic and Monod models are used to describe the effects of pH and colony size, respectively. Toxigenic parameters are estimated by comparing model simulations to the results of two published studies, with fair consistency in the two sets of parameters. In comparisons with other studies, the model did not correctly project the effects of spore load, but did correctly predict toxigenic behaviors relating to the effects of temperature and temperature cycling. The model provides a theoretical explanation for observed temporal shifts in the optimum temperature for toxigenesis, and for a hyperbolic relationship between heat units and time to toxigenesis with and without temperature cycling.