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INTRODUCTION: Aflatoxins, potent carcinogens produced by Aspergillus species, present significant health risks and commonly contaminate herbal products such as Chrysanthemum morifolium. Detecting these toxins in C. morifolium proves challenging due to the complex nature of the herbal matrix and the fluctuating levels of toxins found in different samples. OBJECTIVES: This study aimed to develop and optimize a novel method for the detection of aflatoxins in C. morifolium using dispersive liquid-liquid microextraction combined with high-performance liquid chromatography-fluorescence detection based on quality by design principles. METHODOLOGY: The method involved determining critical method attributes and parameters through the Plackett-Burman design, followed by optimization using the Box-Behnken design. Monte Carlo simulation was employed to establish a design space, which was experimentally verified. Method validation was performed to confirm accuracy, precision, and stability. RESULTS: The developed method exhibited excellent linearity (R2 > 0.9991) for aflatoxins B1, B2, G1, and G2 across a range of concentrations, with recovery rates between 85.52% and 102.01%. The validated method effectively quantified aflatoxins in C. morifolium under different storage conditions, highlighting the impact of temperature and storage time on aflatoxin production. CONCLUSION: This study successfully established a reliable and effective method for the detection of aflatoxins in C. morifolium, highlighting the importance of strict storage conditions to reduce aflatoxin contamination. Using a quality by design framework, the method demonstrated robustness and high analytical performance, making it suitable for routine quality control of herbal products.

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Cereals are frequently contaminated by aflatoxins (AFs). The objective of this study was to develop an efficient extraction materials for rapidly extracting and detecting AFs. A novel amino-functionalized benzodiimidazole linkage magnetic covalent organic framework (Fe3O4@BB-COF) was simply fabricated by one-step cyclization and aromatization. The Fe3O4@BB-COF, having multiple N-containing active sites, exhibited excellent extraction capability towards AFs due to synergistic interactions, including the π-π interactions, hydrogen bonding interactions, polar interactions, electrostatic interactions and Lewis acid-base interactions. The Fe3O4@BB-COF based MSPE method for detecting aflatoxins has advantages of simple operation, short extraction time (6 min), and low material consumption (2 mg). This method exhibited satisfactory linearity (0.05-20 µg/kg), and sensitivity (0.01-0.45 µg/L for the detection limits) and accuracy (76.8-97.1 % for recovery) and was successfully applied for extracting and detecting AFs in cereals.

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A functional material was developed with specific recognition properties for aflatoxins for pre-processing enrichment and separation in the detection of aflatoxins in Chinese herbal medicines. In the experiment, ethyl coumarin-3-carboxylate, which has a highly similar structure to the oxonaphthalene o-ketone of aflatoxin, was selected as a pseudo-template, zinc acrylate, neutral red derivative, and methacrylic acid, which have complementary functions, were selected as co-monomers to prepare a pseudo-template multifunctional monomer molecularly imprinted polymer (MIP). The MIP obtained under the optimal preparation conditions has a maximum adsorption capacity of 0.036 mg/mg and an imprinting factor of 3.67. The physical property evaluation of the polymers by Fourier infrared spectrometer, scanning electron microscopy, pore size analyzer, thermogravimetric analyzer, and diffuse reflectance spectroscopy showed that the MIP were successfully prepared and porous spherical-like particles were obtained. The synthesized polymer was used as a solid-phase extraction agent for the separation of aflatoxins from the extract of spina date seed. The linear range of the developed method was 10-1000 ng/mL, the limit of detection was 0.36 ng/mL, the limit of quantification was 1.19 ng/mL, and the recoveries of the extracts at the concentration level of 0.2 µg/mL were in the range 88.0-93.4%, with relative standard deviations (RSDs) of 1.97% (n). The results showed that the preparation of MIPs using ethyl coumarin-3-carboxylate as a template was simple, economical, and convenient. It is expected to become a promising functional material for the enrichment and separation aflatoxins from complex matrices.

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Aflatoxins pose a major health concern and require strict monitoring in food products. Existing methods rely on hazardous organic solvents for extraction, prompting the development of a greener alternative. This study explores deep eutectic solvents (DESs) for aflatoxin extraction from pistachios, a valuable food product prone to aflatoxin contamination. The proposed method utilizes DES extraction followed by solid-phase extraction cleanup and ultrahigh-performance liquid chromatography coupled with fluorescence detector analysis. Recovery rates ranged from 85.5 to 99.1% for pistachios spiked with 1-8 ng/g aflatoxins, in compliance with EU regulations, with coefficients of variation less than 2.94%. The method demonstrates good sensitivity with limits of detection and quantification in the range of 0.02-0.22 ng/g and 0.05-0.72 ng/g, respectively. Greenness assessment using AGREEPrep and White Analytical Chemistry metrics confirms its environmental sustainability. This approach offers a promising, safer, and more eco-friendly alternative for aflatoxin extraction from complex food matrices like pistachios.

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Aflatoxins are frequent contaminants of maize especially in the face of climate change with deleterious health and socio-economic impacts. South Africa is ranked 9th maize exporter globally; hence, insights need to be gained in terms of the maize value chain in South Africa with respect to aflatoxin contamination to evaluate consumers' exposure. High-performance liquid chromatography (HPLC) technique was used in this study to quantify aflatoxins in South African commercial maize. One thousand and twenty-eight (1028) maize samples were collected across six distinct agro-climatic regions over five harvest seasons (2017 - 2021). A total of 205 samples (19.94 %) were found to be contaminated with aflatoxins, with mean total aflatoxin concentration of 64.17 ppb amongst the contaminated samples, which is above the SA regulatory limit of 20 ppb for animal consumption. The year 2018 recorded the highest mean total aflatoxin value while North-West agro-climatic region had the highest mean total aflatoxin value. Drastic reduction in average rainfall significantly influence aflatoxin contamination of South African maize.

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In order to understand the status of aflatoxin contamination in dried chilli products in Gansu Province and the risk of dietary exposure, a total of 106 samples of dried chilli products from farmers' markets and supermarkets in 14 prefecture-cities of Gansu Province were collected and analysed by isotope dilution liquid chromatography-tandem mass spectrometry. The results showed that the detection rate of aflatoxin in dried chilli products in Gansu Province was 30.2%, and the average level was 1.57 µg/kg. The detection rates of dried chillies, paprika, and chilli powders were 16.7%, 43.6%, and 46.2%, respectively. The detection rates of aflatoxin in dried chilli products from shops and farmers' markets were 22.5% and 40.0%, respectively. The dietary exposure of AFB1 was 0.0001 µg/kg bw/day, and the MOE calculated from its average concentration was 305.

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Because of the medical importance of cumin as well as it being one of the food additives to many Saudi dishes, there was a need to study the fungal load of this type of spice. This study aimed to determine the mycological profile of the retail black and green cumin distributed in different markets at western region, Saudi Arabia, using the dilution plat method on dichloran 18% glycerol (DG18) agar and incubation at 25°C. Using morphological criteria and molecular markers (internal transcribed spacer sequence), 39 species belonging to 18 genera were collected from different black cumin (33 species belonging to 17 genera) and green cumin (25 species belonging to 9 genera). Alternaria alternata, Aspergillus flavus, A. niger, A. ochraceus, Cladosporium cladosporioides, and Stemphylium botryosum were the most prevalent. Black cumin harbors fungal counts reaching 545 colony-forming units (CFU)/g, while green cumin included 500 CFU/g. Also, the natural occurrence of aflatoxins and ochratoxin A was also measured. Seventy-two cumin samples (90% of tested samples) showed toxin contamination. Aflatoxins and ochratoxin A ranged from 9.35 to 3.9 PPB in black cumin samples and from 4.08 to 5.75 PPB in green cumin samples.

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One of the most promising biologically based nanomanufacturing processes is the production of selenium nanoparticles (SeNPs) by fungi. The use of these biosynthesized nanoparticles in agricultural practices has emerged as a new approach for controlling pathogen growth and mycotoxin production. In the present study, different chemical and physical parameters were investigated for the growth of Fusarium oxysporum (CCASU-2023-F9) to increase selenite reduction and obtain the highest yield of selenium nanoparticles (SeNPs). Fusarium oxysporum (CCASU-2023-F9) exhibited tolerance to up to 1 mM sodium selenite (Na2SeO3), accompanied by red coloration of the medium, which suggested the reduction of selenite and the formation of selenium nanoparticles (SeNPs). Reduced selenite was quantified using inductively coupled plasma‒mass spectrometry (ICP-MS), and the results revealed that Fusarium oxysporum (CCASU-2023-F9) is able to transform 45.5% and 50.9% of selenite into elemental selenium by using fructose and urea as the best carbon and nitrogen sources, respectively. An incubation temperature of 30 °C was the best physical condition at which 67.4% of the selenite was transformed into elemental selenium. The results also indicated that pH 7 was the optimum pH, as it displayed 27.2% selenite reduction with a net dry weight of 6.8 mg/mL. Increasing the concentration of sulfate resulted in a significant increase in selenite reduction, as it reached a maximum value of 75.3% at 0.15% g/ml sulfate. The maximum reduction in sodium selenite content was 85.2% at a C/N ratio of 2:1. The biosynthesized SeNPs exhibited antifungal activity against several fungi, such as Aspergillus flavus, Aspergillus niger, and Fusarium oxysporum, that were isolated from animal and poultry feed. Elevated SeNP concentrations (10500 ppm) significantly inhibited fungal growth. SeNPs at a concentration of 5000 ppm inhibited aflatoxin production (B1, B2, G1, and G2) by A. flavus, in addition to inhibiting mycotoxin production (T2 toxin, fumonisin B1, zearaleone, fusarin C, and moniliformin) by F. oxysporum. In conclusion, the results revealed favorable nutritional conditions for the maximum production of SeNPs by Fusarium oxysporum (CCASU-2023-F9) and indicated the marked inhibitory effect of SeNPs on mycotoxins that contaminate animal feed, causing serious consequences for animal health, and that lead to improving the quality of commercially produced animal feed. The obtained results can serve as a basis for commercial applicability.

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Globally, maize (Zea mays L.) is deemed an important cereal that serves as a staple food and feed for humans and animals, respectively. Across the East African Community, maize is the staple food responsible for providing over one-third of calories in diets. Ideally, stored maize functions as man-made grain ecosystems, with nutritive quality changes influenced predominantly by chemical, biological, and physical factors. Food spoilage and fungal contamination are convergent reasons that contribute to the exacerbation of mycotoxins prevalence, particularly when storage conditions have deteriorated. In Kenya, aflatoxins are known to be endemic with the 2004 acute aflatoxicosis outbreak being described as one of the most ravaging epidemics in the history of human mycotoxin poisoning. In Tanzania, the worst aflatoxin outbreak occurred in 2016 with case fatalities reaching 50%. Similar cases of aflatoxicoses have also been reported in Uganda, scenarios that depict the severity of mycotoxin contamination across this region. Rwanda, Burundi, and South Sudan seemingly have minimal occurrences and fatalities of aflatoxicoses and aflatoxin contamination. Low diet diversity tends to aggravate human exposure to aflatoxins since maize, as a dietetic staple, is highly aflatoxin-prone. In light of this, it becomes imperative to formulate and develop workable control frameworks that can be embraced in minimizing aflatoxin contamination throughout the food chain. This review evaluates the scope and magnitude of aflatoxin contamination in post-harvest maize and climate susceptibility within an East African Community context. The paper also treats the potential green control strategies against Aspergillus spoilage including biocontrol-prophylactic handling for better and durable maize production.

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Aflatoxins are one of the most toxic mycotoxins and can cause serious harm to humans and animals. Adsorption is a practical decontamination technique favored by the industry because of its advantages of low cost, speed and simplicity, and environmental friendliness. In this work, the adsorption features of activated carbon and chitosan were fabricated in a composite through chemical co-precipitation to improve its properties for adsorption. Furthermore, the capacity of the synthesized chitosan and acid-washed activated carbon composite (CS-AAC) to attenuate the aflatoxins in contaminated peanut oil and the adsorption capacity at different initial aflatoxins content, contact duration, and temperature were evaluated. The results showed a higher adsorption capacity (removal efficiency to 93.45% of AFB1, 94.05% of AFB2, 89.16% of AFG1, 83.26% of AFG2). The Freundlich isothermal and D-R model and the pseudo-second-order rate expression both implied a good correlation with the test data and explained the adsorption mechanism well. The adsorption mechanism was found to be accomplished primarily via ion exchange and chelation. According to thermodynamic results (△G < 0, △H > 0, △S > 0), the adsorption process was endothermic and spontaneous. Compared to acid-washed activated carbon, CS-AAC enhanced the retention of VE and sterols (especially VE by 23%), and the safety of CS-AAC adsorbent was explored by cellular experiments. In conclusion, CS-AAC is a promising adsorbent material for the removal of aflatoxins from edible oils.

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Designing and implementing processing procedures for producing safe complementary foods in dynamic and unregulated food systems where common food staples are frequently contaminated with mycotoxins is challenging. This paper presents lessons about minimizing aflatoxins (AF) in groundnut flour and AF and/or fumonisins (FUM) in maize and groundnut pre-blended flour for complementary feeding in the context of a dietary research intervention in rural Tanzania. The flours were processed in collaboration with Halisi Products Limited (Halisi), a medium scale enterprise with experience in milling cereal-based flours in Arusha, Tanzania. Using a hazard analysis critical control point (HACCP) approach for quality assurance, two critical control points (CCPs) for AF in processing the pre-blended flour were identified: 1) screening maize before procurement, and 2) blending during the processing of each constituent flour. Blending of maize flour was also identified as a CCP for FUM. Visual inspection during screening and sorting were identified as important control measures for reducing AF, but these steps did not meet the criteria for a CCP due to lack of objective measurement and verifiable standards for AF. The HACCP approach enabled the production of low AF (<5 µg/kg) and FUM (<2 µg/g) flours with low rejection rates for the final products. The paper presents practical lessons that could be of value to a range of commercial processors in similar low- and middle-income contexts who are keen on improving food quality.

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Avian coccidiosis, a common disease caused by Eimeria species, results in significant losses in global poultry production. Mycotoxins are low-molecular-weight natural products (i.e., small molecules) produced as secondary metabolites by filamentous fungi and they have the potential to economically and significantly affect global poultry production. Little is known about the relationship between mycotoxins and avian coccidiosis, although they often co-occur in the field. This comprehensive review examines the intricate relationship between mycotoxins and avian coccidiosis, in particular how mycotoxins, including aflatoxins, ochratoxins, trichothecenes as well as Fusarium mycotoxins, compromise the health of the poultry flock and open the door to Eimeria parasites in the gut. In addition, this review sheds light on the immunosuppressive effects of mycotoxins, their disruption of cellular signaling pathways, and the consequent exacerbation of coccidiosis infections. The mechanisms of mycotoxin toxicity are also reviewed, emphasizing direct damage to intestinal epithelial cells, impaired nutrient absorption, inflammation, oxidative stress, and changes in the gut microbiota. Finally, the consequences for the prevention and treatment of coccidiosis when mycotoxins are present in the feed are discussed. This review emphasizes the need for effective management strategies to mitigate the combined risks of mycotoxins and coccidiosis and highlights the complexity of diagnosing and controlling these interrelated problems in poultry. The review advocates a holistic approach that includes strict feed management, disease prevention measures and regular monitoring to maintain the health and productivity of poultry against these significant challenges.

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Cassava is the second most important staple food crop for Uganda and is prone to contamination with mycotoxins. This study aimed at understanding the current agricultural practices, their potential influence on mycotoxin occurrence, as well as assessing mycotoxin knowledge among key cassava value chain actors, including farmers, wholesalers, and processors. Data were collected through individual interviews (210), key informant interviews (34), and 4 focus group discussions. The findings revealed that 51% of farmers peeled cassava directly on bare ground, resulting in direct contact with soil that potentially harbors mycotoxin-producing fungi, such as Aspergillus section Flavi. During postharvest handling, 51.6% of farmers dried cassava chips directly on bare ground. Nearly, all (95.2%) of wholesalers packed cassava chips in local gunny bags and placed them on ground instead of pallets. In the processing of cassava chips into flour, only one of the 14 processing machines was certified by the Uganda National Bureau of Standards. Additionally, there was only one processing machine available for every 180 (1:180) consumers bringing their cassava for processing. 50.8% of cassava consumers interviewed admitted to consuming cassava flour regardless of quality, while 73% blended cassava flour with flour from mycotoxin-susceptible crops mainly maize, millet, and sorghum. Most (96.2%) of the people along the cassava value chain did not understand what the term mycotoxins meant. However, 56% of interviewed respondents were familiar with the term aflatoxins. Of the cassava value chain actors aware of mycotoxins, 82.9% knew of methods for reducing aflatoxin contamination, but only 40.9% were putting such methods into practice. More farmers (47.9%) managed aflatoxins compared to wholesalers (33.3%) and processors (21.4%). Knowledge on aflatoxins was significantly associated with value chain actor (P = 0.026), head of household (P = 0.004), region (P = 0.033), age (P = 0.001), and experience (P = 0.001). This study highlights the critical areas of mycotoxin contamination within the cassava value chain in Uganda and underscores the need to improve the knowledge among value chain actors especially farmers.

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Foodborne hazardous factors pose a significant risk to public health, emphasizing the need for the development of sensitive and user-friendly detection strategies to effectively manage and control these risks in the food supply chain. Pyrococcus furiosus argonaute (PfAgo)-based biosensing approaches have been extensively explored due to its built-in signal amplification. However, the property that PfAgo is a DNA-guided DNA endonuclease has enabled almost all the existing PfAgo-based reports to be used for the detection of nucleic acids. To lend PfAgo toolbox to extended non-nucleic acid detection, we systematically investigated the mechanism characteristic of PfAgo' preference for guide DNA (gDNA) and proposed a gDNA dephosphorylation-modulated PfAgo sensor for the detection of non-nucleic acid targets. Our results indicated that PfAgo exhibits preference for 5'-phosphorylated gDNA at a specific ratio of PfAgo to gDNA concentration. Leveraging this PfAgo' preference and the dephosphorylation activity of alkaline phosphatase (ALP), ALP could be detected as low as 2.7 U/L. Furthermore, the PfAgo was coupled with immunolabelled ALP to develop a PfAgo-based fluorescence immunosensor, which achieves aflatoxins B1 detection with a detection limit of 29.89 pg/mL and exhibits satisfactory recoveries in wheat and maize samples. The developed method broadens the application scope of PfAgo toolbox, and provides a simple, sensitive, and universal detection platform for a variety targets.

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Breast milk is one of the many distinct forms of food that can be contaminated with aflatoxin M1 (AFM1). They may be consumed by eating contaminated foods, such as contaminated meat and crops, which would then be present in breast milk and cause health problems, including nervous system disorders and cancers of the lungs, liver, kidneys, and urinary tract. However, the prevalently inconsistent explanation of prevalence and concentration remains a big challenge. Thus, this meta-analysis was conducted to determine the prevalence and concentration of harmful chemicals in breast milk in an African context. The databases MEDLINE, PubMed, Embase, SCOPUS, Web of Science, and Google Scholar were searched for both published and unpublished research. To conduct the analysis, the collected data were exported to Stata version 18. The results were shown using a forest plot and a prevalence with a 95% confidence interval (CI) using the random-effects model. The Cochrane chi-square (I2) statistics were used to measure the studies' heterogeneity, and Egger's intercept was used to measure publication bias. This review included twenty-eight studies with 4016 breast milk samples and newborns. The analysis showed the overall prevalence and concentration of aflatoxin M1 in breast milk were 53% (95% CI 40, 65; i2 = 98.26%; P = 0.001). The pooled mean aflatoxin M1 concentration in breast milk was 93.02 ng/l. According to this study, the eastern region of Africa was 62% (95% CI 39-82) profoundly affected as compared to other regions of the continent. In subgroup analysis by publication year, the highest level of exposure to aflatoxins (68%; 95% CI 47-85) was observed among studies published from 2010 to 2019. This finding confirmed that more than half of lactating women's breast milk was contaminated with aflatoxin M1 in Africa. The pooled mean aflatoxin M1 concentration in breast milk was 93.02 ng/l. According to this study, the eastern region of Africa was profoundly affected compared with other regions. Thus, the government and all stakeholders must instigate policies that mitigate the toxicity of aflatoxins in lactating women, fetuses, and newborns.

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Aflatoxins are mycotoxins that contaminate staple foods globally and pose a significant health risk. To the best of our knowledge, information on the occurrence of aflatoxins in Bhutanese diets is scarce. This study aimed to estimate the aflatoxin levels in selected foodstuffs in Bhutan and determine the health risk associated with aflatoxin exposure. Ten different types of food commodities were randomly collected from farmers' markets, shelves of supermarkets, and wholesale and retail shops from 20 districts of the country. The samples were subjected to analysis by an enzyme-linked immunosorbent assay for both total aflatoxins (B1, B2, G1 and G2) and aflatoxin B1. Among the 315 samples included, 48.81% and 79.35% were positive for total aflatoxins and aflatoxin B1, respectively. The overall mean total aflatoxin concentration was 11.49 ± 12.83 µg/kg, and that for B1 was 17.62 ± 23.99 µg/kg. The most prevalent food commodity with the highest aflatoxin contamination was chili products. In addition, the estimated daily intake and margin of exposure to aflatoxin B1 via the consumption of chili products ranged from 0.98 to 5.34 ng kg-1 bw day-1 and from 74.90 to 408.10, indicating a risk for public health. The liver cancer risk was estimated to be 0.01 and 0.007 cancers per year per 100,000 population resulting from the consumption of chili products. The present findings revealed the presence of total aflatoxins and aflatoxin B1 in the selected samples. The margin of exposure values was exorbitant, demanding a stringent public health measure. Notably, these results suggest the need for routine monitoring of aflatoxin contamination in the region and stress rigorous safety management strategies to reduce exposure.

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UPLC-MS/MS analytical conditions for the analysis of aflatoxins in spices were optimized and validated in this study. Liquid-liquid partition-based protocols for the cleaning up of extracts using common organic solvents such as acetonitrile, hexane, and ethyl acetate were developed and validated. The developed liquid-liquid partition methods were compared with immuno-affinity column and QuEChERS clean-up methods for the UPLC-MS/MS analysis of aflatoxins in 8 spices. The reduction of lipophilic components using the partition with hexane is particularly useful in spices like red pepper that have higher levels of fatty acids, carotenoids, sterols, triterpenoids, etc. The subsequent partitioning with ethyl acetate considerably reduced the matrix interference from the polar components and increased the sensitivity. The cleaning up of spice extracts using liquid-liquid partition techniques resulted in limits of quantification (LOQ) of 2-5 µgL-1 in UPLC-MS/MS analysis. Trueness, repeatability, and reproducibility of the methods were in acceptable ranges. The accuracy of the developed methods was further verified by analyzing aflatoxins in naturally incurred samples of spices and comparing the results with those obtained from the immuno-affinity column cleanup-HPLC-FD method.

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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.

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Sugarcane is one of the most important crops in the world. It is also considered the most popular fresh juice in Egypt. The sugar content of the sugarcane stem represents the main source of fungal growth. This study aimed to investigate the natural co-occurrence of fungi in sugarcane plants and juice, test of aflatoxins production by aflatoxigenic fungi, and improve the quality of sugarcane juice. The obtained results indicated a notable decrease in all physical parameters of the naturally infected sugarcane plants. Isolation of fungi from sugarcane plant and juice from three localities revealed that the highest mean fungal count was recorded in sugarcane rootlets (173.55 cfu/cm), followed by sugarcane stem (94.88 cfu/cm), while sugarcane juice had the least mean fungal count (24.33 cfu/mL). The frequency of the isolated fungi associated with sugarcane plant yielded 781 fungal isolates for rootlets, 427 fungal isolates for stems, and 219 fungal isolates for juice. Four isolates of Aspergillus parasiticus were aflatoxins producers. Higher aflatoxin quantity (1434.92 ng/mL) was produced by A. parasiticus (isolate No. 21) from sugarcane stem, while A. parasiticus (isolate No. 5) from sugarcane juice was less aflatoxins producer (276.95 ng/mL). On the other hand, lemon juice showed a significant reduction effect on the fungal count of peeled and non-peeled sugarcane juice. In which the highest reduction percent of the fungal count was recorded with 20% conc. of lemon on peeled sugarcane juice (36.04%).The obtained results concluded that lemon juice was found to decrease the fungal contaminants and improve the quality of sugarcane juice.

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Aflatoxins (AFs) are highly carcinogenic metabolites produced by Aspergillus species that can contaminate critical food staples, leading to significant health and economic risks. The cytochrome P450 monooxygenase AflG catalyzes an early step in AF biosynthesis, resulting in the conversion of averantin (AVN) to 5'-hydroxy-averantin. However, the molecular mechanism underlying the AflG-AVN interaction remains unclear. Here, we sought to understand the structural features of AflG in complex with AVN to enable the identification of inhibitors targeting the AflG binding pocket. To achieve this goal, we employed a comprehensive approach combining computational and experimental methods. Structural modeling and microsecond-scale molecular dynamics (MD) simulations yielded new insights into AflG architecture and unveiled unique ligand binding conformations of the AflG-AVN complex. High-throughput virtual screening of more than 1.3 million compounds pinpointed specific subsets with favorable predicted docking scores. The resulting compounds were ranked based on binding free energy calculations and evaluated with MD simulations and in vitro experiments with Aspergillus flavus. Our results revealed two compounds significantly inhibited AF biosynthesis. Comprehensive structural analysis elucidated the binding sites of competitive inhibitors and demonstrated their regulation of AflG dynamics. This structure-guided pipeline successfully enabled the identification of novel AflG inhibitors and provided novel molecular insights that will guide future efforts to develop effective therapeutics that prevent AF contamination.