Determination of mycobiota and aflatoxin contamination in commercial bee pollen from eight provinces and one autonomous region of China.

The co-occurrence of fungi and mycotoxins in various foods has been frequently reported in many countries, posing a serious threat to the health and safety of consumers. In this study, the mycobiota in five types of commercial bee pollen samples from China were first revealed by DNA metabarcoding. Meanwhile, the content of total aflatoxins in each sample was investigated by high-performance liquid chromatography with fluorescence detection. The results demonstrated that Cladosporium (0.16 %-89.29 %) was the most prevalent genus in bee pollen, followed by Metschnikowia (0-81.12 %), unclassified genus in the phylum Ascomycota (0-81.13 %), Kodamaea (0-73.57 %), and Penicillium (0-36.13 %). Meanwhile, none of the assayed aflatoxins were determined in the 18 batches of bee pollen samples. In addition, the fungal diversity, community composition, and trophic mode varied significantly among five groups. This study provides comprehensive information for better understanding the fungal communities and aflatoxin residues in bee pollen from different floral origins in China.

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.

Optimization and synthesis of a novel sorbent composite based on magnetic chitosan-amine-functionalized bimetallic MOF for the simultaneous dispersive solid-phase microextraction of four aflatoxins in real water, herbal distillate, and food samples.

Aflatoxins (AFs), an important category of pollutants, are formed in many foods and adversely affect human health. Therefore, their determination is critical to ensuring human food health. An efficient dispersive solid-phase microextraction technique was developed as a simple and straightforward sample preparation technique for determination of four aflatoxins using a high-performance liquid chromatography (HPLC) fluorescence detector. A novel efficient, green sorbent for extracting AFs was synthesized based on hydrothermal and chemical strategies. The amounts of three sorbent components were optimized using a mixture design (simplex lattice design), including 14 experiments. The optimal amount of amino-bimetallic Fe/Ni-MIL-53 nanospheres, chitosan, and magnetic Fe3O4 nanoparticles as sorbent components was 0.87, 0.67, and 0.47 g, respectively. Also, various factors affecting the process of AF determination were studied and optimized in two successive experimental designs, including the definitive screening design and the Box-Behnken design. Under optimal conditions, the linear ranges for measuring aflatoxin B1, aflatoxin B2, aflatoxin G1, and aflatoxin G2 were 0.05-82.6, 0.07-86.4, 0.08-85.7, and 0.07-89.5 ng mL-1, respectively. The relative standard deviations under inter-day and intra-day conditions for measuring AFs at three analyte concentrations were determined in triplicate analysis and were in the ranges of 3.7-4.6% and 4.9-6.1% for water sample analysis, respectively. The qualitative detection limits for determining AFs were between 0.01 and 0.05 ng mL-1. The pre-concentration factor of the method for measuring AFs ranged from 739.7 to 802.1. The proposed method was used for determining AFs in several real samples, including herbal distillate, black tea, corn, and real water samples. The relative recovery and standard deviation were 87.8-97.8% and 4.10-6.82%, respectively.

Allium cepa tests: A plant-based tool for the early evaluation of toxicity and genotoxicity of newly synthetized antifungal molecules.

Many fungal genera such as Aspergillus, Penicillium, Fusarium and Alternaria are able to produce, among many other metabolites, the aflatoxins, a group of toxic and carcinogenic compounds. To reduce their formation, synthetic fungicides are used as an effective way of intervention. However, the extensive use of such molecules generates long-term residues into the food and the environment. The need of new antifungal molecules, with high specificity and low off-target toxicity is worth. The aim of this study was to evaluate: i) the toxicity and genotoxicity of newly synthesized molecules with a good anti-mycotoxic activity, and ii) the suitability of the Allium cepa multi-endpoint assay as an early screening method for chemicals. Eight compounds were tested for toxicity by using the A. cepa bulb root elongation test and for genotoxicity using the A. cepa bulb mitotic index, micronuclei and chromosome aberrations tests. Three molecules showed no toxicity, while two induced mild toxic effects in roots exposed to the highest dose (100 µM). A more pronounced toxic effect was caused by the other three compounds for which the EC50 was approximately 50 µM. Furthermore, all molecules showed a clear genotoxic activity, both in terms of chromosomal aberrations and micronuclei. Albeit the known good antifungal activity, the different molecules caused strong toxic and genotoxic effects. The results indicate the suitability of experiments with A. cepa as a research model for the evaluation of the toxic and genotoxic activities of new molecules in plants before they are released into the environment.

Microfluidizing Technique Application for Algerian Cymbopogon citratus (DC.) Stapf Effects Enhanced Volatile Content, Antimicrobial, and Anti-Mycotoxigenic Properties.

Medicinal plant extracts are a promising source of bioactive minor contents. The present study aimed to evaluate the distinguished volatile content of Algerian Cymbopogon citratus (DC.) Stapf before and after the microfluidization process and their related antimicrobial and anti-mycotoxigenic impacts and changes. The GC-MS apparatus was utilized for a comparative examination of Algerian lemongrass essential oil (LGEO) with its microfluidization nanoemulsion (MF-LGEO) volatile content. The MF-LGEO was characterized using Zetasizer and an electron microscope. Cytotoxicity, antibacterial, and antifungal activities were determined for the LGEO and MF-LGEO. The result reflected changes in the content of volatiles for the MF-LGEO. The microfluidizing process enhanced the presence of compounds known for their exceptional antifungal and antibacterial properties in MF-LGEO, namely, neral, geranial, and carvacrol. However, certain terpenes, such as camphor and citronellal, were absent, while decanal, not found in the raw LGEO, was detected. The droplet diameter was 20.76 ± 0.36 nm, and the polydispersity index (PDI) was 0.179 ± 0.03. In cytotoxicity studies, LGEO showed higher activity against the HepG2 cell line than MF-LGEO. Antibacterial LGEO activity against Gram-positive bacteria recorded an inhibitory zone from 41.82 ± 2.84 mm to 58.74 ± 2.64 mm, while the zone ranged from 12.71 ± 1.38 mm to 16.54 ± 1.42 mm for Gram-negative bacteria. Antibacterial activity was enhanced to be up to 71.43 ± 2.54 nm and 31.54 ± 1.01 nm for MF-LGEO impact against Gram-positive and Gram-negative pathogens. The antifungal effect was considerable, particularly against Fusarium fungi. It reached 17.56 ± 1.01 mm and 13.04 ± 1.37 mm for LGEO and MF-LGEO application of a well-diffusion assay, respectively. The MF-LGEO was more promising in reducing mycotoxin production in simulated fungal growth media due to the changes linked to essential compounds content. The reduction ratio was 54.3% and 74.57% for total aflatoxins (AFs) and ochratoxin A (OCA) contents, respectively. These results reflect the microfluidizing improvement impact regarding the LGEO antibacterial, antifungal and anti-mycotoxigenic properties.

Comparing the effects of essential oils and methanolic extracts on the inhibition of Aspergillus flavus and Aspergillus parasiticus growth and production of aflatoxins.

The antifungal and antiaflatoxigenic effects of four distinct plant species against Aspergillus flavus and Aspergillus parasiticus were investigated. Essential oils and methanolic extracts were prepared from aerial parts of Lippia javanica, Ocimum gratissimum, Satureja punctata, and stem barks of Toddalia asiatica by hydro-distillation and maceration, respectively. The poisoned food method was used to confirm the antifungal activity of essential oils and methanolic extracts from four different plant species against Aspergillus flavus and Aspergillus parasiticus, and high-performance liquid chromatography was used to quantify the antiaflatoxigenic activity. The essential oils of Satureja punctata and Lippia javanica showed the highest antiaflatoxigenic activity against the fungi strains tested at concentrations of 1.25, 2.5, and 5 µL/mL, followed by Ocimum gratissimum essential oil while Toddalia asiatica essential oil exerted moderate antiaflatoxigenic activity. Meanwhile, the methanolic extracts showed a wide spectrum of low to high antifungal and antiaflatoxigenic activities at concentrations of 125, 250, and 500 µg/mL against A. flavus and A. parasiticus. This study has indicated that the essential oils of Satureja punctate, Lippia javanica, and Ocimum gratissimum had substantial antifungal and antiaflatoxigenic activities compared to their methanolic extracts, while Toddalia asiatica methanolic extract had a moderate antifungal activity compared to its essential oil.

Antifungal Effect of Autochthonous Aromatic Plant Extracts on Two Mycotoxigenic Strains of Aspergillus flavus.

This study identified the compounds obtained from four native Dehesa plants, which were holm oak, elm, blackberry and white rockrose, and evaluated their ability to inhibit the growth and production of aflatoxins B1 and B2 of two strains of mycotoxigenic Aspergillus flavus. For this purpose, phenolic compounds present in the leaves and flowers of the plants were extracted and identified, and subsequently, the effect on the growth of A. flavus, aflatoxin production and the expression of a gene related to its synthesis were studied. Cistus albidus was the plant with the highest concentration of phenolic compounds, followed by Quercus ilex. Phenolic acids and flavonoids were mainly identified, and there was great variability among plant extracts in terms of the type and quantity of compounds. Concentrated and diluted extracts were used for each individual plant. The influence on mold growth was not very significant for any of the extracts. However, those obtained from plants of the genus Quercus ilex, followed by Ulmus sp., were very useful for inhibiting the production of aflatoxin B1 and B2 produced by the two strains of A. flavus. Expression studies of the gene involved in the aflatoxin synthesis pathway did not prove to be effective. The results indicated that using these new natural antifungal compounds from the Dehesa for aflatoxin production inhibition would be desirable, promoting respect for the environment by avoiding the use of chemical fungicides. However, further studies are needed to determine whether the specific phenolic compounds responsible for the antifungal activity of Quercus ilex and Ulmus sp. produce the antifungal activity in pure form, as well as to verify the action mechanism of these compounds.

Optimization and Validation of Dispersive Liquid-Liquid Microextraction for Simultaneous Determination of Aflatoxins B1, B2, G1, and G2 in Senna Leaves and Pods Using HPLC-FLD with Pre-Column Derivatization.

Dispersive liquid-liquid microextraction (DLLME) was optimized for the simultaneous extraction of aflatoxins (AFB1, AFB2, AFG1, and AFG2) from powdered senna leaves and pods. Detection was performed using high-performance liquid chromatography with fluorescence detection (HPLC-FLD) and pre-column derivatization. The parameters affecting the DLLME extraction efficiency were evaluated. Chloroform (200 µL) was used as an extraction solvent, 500 µL of distilled water was used as a dispersive solvent, and the extraction was performed at pH 5.6 with no salt added. The optimized method was validated using leaves and pods according to the European Commission guidelines. The linear range for all aflatoxins was 2-50 µg/kg, with values for regression coefficients of determination exceeding 0.995. The recoveries of spiked senna leaves and pods were in the ranges of 91.77-108.71% and 83.50-102.73%, respectively. The RSD values for intra-day and inter-day precisions were in the ranges of 2.30-7.93% and 3.13-10.59%, respectively. The limits of detection and quantification varied in the ranges of 0.70-1.27 µg/kg and 2.13-3.84 µg/kg, respectively. The validated method was successfully applied for the quantification of aflatoxins in 60 real samples of dried senna leaves and pods.

Efficient and simultaneous removal of aflatoxin B1, B2, G1, G2, and zearalenone from vegetable oil by use of a metal-organic framework absorbent.

Vegetable oils are usually cocontaminated with different mycotoxins, including aflatoxins and zearalenone, which cause significant food safety issues. Establishment of multitarget, high-efficiency, and low-cost adsorption methods are considered to be ideal solutions for mycotoxin removal in vegetable oils. In this study, we used metal-organic frameworks (MOFs) were used for the simultaneous removal of aflatoxins and zearalenone from vegetable oils. The results showed that MOF-235 simultaneously removed, within 30 min, more than 96.1% of aflatoxins and 83.3% of zearalenone from oils, and oils treated with MOF-235 exhibited di minimis cytotoxicity. Thus, synthesized MOF-235 exhibited sufficient efficacy to remove the targeted residues, as well as safety and reusability, which could be applied as a novel potential adsorbent in the removal of multiple mycotoxins from contaminated vegetable oils.

Dispersive Magnetic Solid-Phase Extraction as a Novelty Sample Treatment for the Determination of the Main Aflatoxins in Paprika.

Dispersive magnetic solid-phase extraction (DMSPE) technique is proposed as a new sensitive and effective sample treatment method for the determination of aflatoxins in paprika samples. DMSPE was followed by ultrahigh-performance liquid chromatography and high-resolution mass spectrometry detection (UHPLC-HRMS) using a non-targeted acquisition mode for the detection of main aflatoxins (aflatoxin G1, G2, B1 and B2) and derivatives. DMSPE was based on the use of magnetic nanocomposite coated with polypyrrole (PPy) polymer and the main experimental parameters influencing the extraction efficiency in adsorption and desorption steps have been studied and optimized. Analyses were performed using 250 µL magnetic PPy nanocomposite into the sample solution, adsorbing the analytes in 30 min and desorbing them with ethyl acetate (2 mL) in 15 min. The method has been validated, obtaining quantification limits between 3.5 and 4.7 µg kg-1 and recoveries between 89.5-97.7%. The high recovery rate, wide detection range and the use for the first time of the reusable Fe3O4@PPy nanomaterial in suspension for solid food matrices, guarantee the usefulness of the method developed for adequate control of aflatoxins levels in paprika. The proposed methodology was applied for the analysis of 31 samples (conventional and organic) revealing the absence of aflatoxins in the samples.

New insights into the persistent effect of transient cinnamaldehyde vapor treatment on the growth and aflatoxin synthesis of Aspergillus flavus.

The antimicrobial effects of continuous treatment with essential oils (EOs) in both liquid and gaseous phases have been intensively studied. Due to their rapid volatility, the effects of EOs on microorganisms after transient treatment are also worth exploring. In this work, the persistent effects of cinnamaldehyde (CA) vapor on Aspergillus flavus were detected by a series of biochemical analyses. Transcriptome analysis was also conducted to study the gene expression changes between recovered and normal A. flavus. When CA vapor was removed, biochemical analyses showed that the oxidative stress induced by the antimicrobial atmosphere was alleviated, and almost all the damaged functions were restored apart from mitochondrial function. Remarkably, the suppressed aflatoxin production intensified, which was confirmed by the up-regulation of most genes in the aflatoxin synthetic gene cluster, the velvet-related gene FluG and the aflatoxin precursor acetyl-CoA. Transcriptomic analysis also demonstrated significant changes in secondary metabolism, energy metabolism, oxidative stress, and amino acid metabolism in the recovery group. Taken together, these findings provide new insights into the mechanisms underlying the response of A. flavus to CA vapor treatment and will guide the rational application of EOs.

Volatiles from Pseudomonas palleroniana Strain B-BH16-1 Suppress Aflatoxin Production and Growth of Aspergillus flavus on Coix lacryma-jobi during Storage.

Semen coicis is not only a traditional Chinese medicine (TCM), but also a typical food in China, with significant medical and healthcare value. Because semen coicis is rich in starch and oil, it can be easily contaminated with Aspergillus flavus and its aflatoxins (AFs). Preventing and controlling the contamination of semen coicis with Aspergillus flavus and its aflatoxins is vital to ensuring its safety as a drug and as a food. In this study, the endosphere bacteria Pseudomonas palleroniana strain B-BH16-1 produced volatiles that strongly inhibited the mycelial growth and spore formation activity of A. flavus. Gas chromatography-mass spectrometry profiling revealed three volatiles emitted from B-BH16-1, of which 1-undecene was the most abundant. We obtained authentic reference standards for these three volatiles; these significantly reduced mycelial growth and sporulation in Aspergillus, with dimethyl disulfide showing the most robust inhibitory activity. Strain B-BH16-1 was able to completely inhibit the biosynthesis of aflatoxins in semen coicis samples during storage by emitting volatile bioactive components. The microscope revealed severely damaged mycelia and a complete lack of sporulation. This newly identified plant endophyte bacterium was able to strongly inhibit the sporulation and growth of Aspergillus and the synthesis of associated mycotoxins, thus not only providing valuable information regarding an efficient potential strategy for the prevention of A. flavus contamination in TCM and food, but potentially also serving as a reference in the control of toxic fungi.

The influence of ultraviolet radiation on aflatoxin producing Aspergillus species' isolated from Iranian rice.

Cereal grains are a favorable habitat for aflatoxin- producing fungus to develop. the current investigation was carried out to evaluate the quantity and kind of contaminated imported grains and rice generated in the province of Shiraz, Iran. A total of 60 random rice samples were taken from paddy fields in October and November 2020. Aspergillus genera were detected using PCR. HPLC was used to determine the quantity and type of aflatoxin and mycotoxins in samples collected. Irradiation studies were carried out utilizing a collimated beam system with wavelengths ranging from 200 to 360 nm. The quality of rice was assessed using UV light therapy on some of the changed factors, such as amylose content, aroma, and brightness [P < 0.05]. Aspergillus genera were found in 33.3% [20 samples of 60] of rice samples after morphological and molecular analysis of the ITS gene. According to the sequencing experiment, 12 strains [60%] were identified as Aspergillus flavus, whereas 8 strains [40%] were identified as Aspergillus parasiticus. Ver-1 and afl-R genes were positive in 12/12 [100%] Aspergillus flavus and 87.5% in Aspergillus parasiticus. According to the HPLC findings, three Aspergillus parasiticus strains [37.5%] were able to create all four types of aflatoxins, and aflatoxins B1, B2, G1, G2 were produced by 16.6% of Aspergillus flavus strains. Aflatoxin-1 (AFG1) was lowered to 35.1, 48.2, 59.9, and 65.2%, significantly, at doses of 1.22, 2.44, 3.66, and 4.88 Jcm-2 [P < 0.01]. Furthermore, at doses of 1.22, 2.44, 3.66, and 4.88 Jcm-2, AFB2 and AFG2 was shown to be reduced by 13.1%, 11.7%, 30.3%, and 28.9%. [P < 0.05]. At a maximum dose of 4.88 Jcm-2, AFB1 was shown to be extremely susceptible to UV irradiation, with a > 70% decrease seen [P < 0.001]. Our findings imply that UV irradiation with lower energy and lower danger can help minimize aflatoxin contamination in food.

Growth performance, digestibility, and plasma metabolomic profiles of Saanen goats exposed to different doses of aflatoxin B1.

Aflatoxin contamination of feed poses a great risk to the global dairy industry. Analyzing the aflatoxin B1 (AFB1)-induced metabonomic changes in ruminants and screening potential biomarkers for early diagnosis of AFB1 exposure is urgently needed. Here, the effects of different doses (0, 50, and 500 µg/kg of the diet, dry matter basis) of AFB1 exposure on digestibility and performance of Saanen goats were studied, and a comprehensive untargeted metabolomic analysis was performed to reveal plasma metabonomic changes caused by the AFB1 exposure. In the current study, AFB1 exposure decreased total-tract nutrient digestibilities, nitrogen retention, total weight gain, and average daily gain of Saanen goats in a dose-dependent manner. Untargeted metabolomics revealed alterations in the plasma metabolome. A total of 3,310 and 1,462 ion peaks were obtained in positive and negative ion modes, respectively. Based on the screening criteria, 1,338 differential metabolites were detected between control and low-dose AFB1 (50 µg/kg) groups, 1,358 metabolites differed between control and high-dose AFB1 (500 µg/kg) groups, and 58 metabolites differed among all groups. Pathway analyses showed that choline metabolism in cancer and glycerophospholipid metabolism were significantly affected by the AFB1 treatments. Moreover, dysregulation of amino acid metabolism was also observed in AFB1 treated goats. The findings provided novel insights into the toxicity of AFB1 in ruminants. Exploring the underlying molecular causes of the changes may help the development of rapid diagnostic techniques and effective interventions for AFB1 intoxication.

The Efficacy of Additives for the Mitigation of Aflatoxins in Animal Feed: A Systematic Review and Network Meta-Analysis.

The contamination of animal feed with aflatoxins is an ongoing and growing serious issue, particularly for livestock farmers in tropical and subtropical regions. Exposure of animals to an aflatoxin-contaminated diet impairs feed efficiency and increases susceptibility to diseases, resulting in mortality, feed waste, and increased production costs. They can also be excreted in milk and thus pose a significant human health risk. This systematic review and network meta-analysis aim to compare and identify the most effective intervention to alleviate the negative impact of aflatoxins on the important livestock sector, poultry production. Eligible studies on the efficacy of feed additives to mitigate the toxic effect of aflatoxins in poultry were retrieved from different databases. Additives were classified into three categories based on their mode of action and composition: organic binder, inorganic binder, and antioxidant. Moreover, alanine transaminase (ALT), a liver enzyme, was the primary indicator. Supplementing aflatoxin-contaminated feeds with different categories of additives significantly reduces serum ALT levels (p < 0.001) compared with birds fed only a contaminated diet. Inorganic binder (P-score 0.8615) was ranked to be the most efficient in terms of counteracting the toxic effect of aflatoxins, followed by antioxidant (P-score 0.6159) and organic binder (P-score 0.5018). These findings will have significant importance for farmers, veterinarians, and animal nutrition companies when deciding which type of additives to use for mitigating exposure to aflatoxins, thus improving food security and the livelihoods of smallholder farmers in developing countries.

Surfactant-Enhanced and Automated Pretreatment Based on Immunoaffinity Magnetic Beads Coupled with Ultra-Performance Liquid Chromatography with Fluorescence Detection for the Determination of Aflatoxins in Peanut Oils.

Sample pretreatment is an important step in the detection and analysis of mycotoxins. However, conventional pretreatment methods are complex, time-consuming, and labor-intensive; moreover, they generate a large amount of organic waste that pollutes the environment. An environmentally friendly and automated pretreatment method is proposed. Without extraction using organic solvents in advance, aflatoxins in peanut oil are directly cleaned and concentrated by immunomagnetic beads with the aid of a reaction solution containing surfactant Tween-20. Under optimal conditions, the proposed pretreatment method requires 40 min to simultaneously pretreat 10-24 samples without any centrifugation or filtering steps, and virtually no organic waste was produced. This pretreatment step was coupled with ultra-performance liquid chromatography-fluorescence detection to develop an effective detection method. The recovery of spiked aflatoxins in peanut oils at different concentrations ranged from 91.6 to 100.8%, and the relative standard deviation was below 5.3%. This reliable method overcomes the drawbacks of conventional methods and offers great application prospects.

Effect of Biodegradable Coatings on the Growth of Aspergillus flavus In Vitro, on Maize Grains, and on the Quality of Tortillas during Storage.

The fungus Aspergillus flavus causes serious damage to maize grains and its by-products, such as tortilla. Currently, animal and plant derivatives, such as chitosan and propolis, and plant extract residues, respectively, are employed as alternatives of synthetic fungicides. The objective of this research was to evaluate the efficacy of several formulations based on propolis-chitosan-pine resin extract on the in vitro growth of A. flavus, the growth of maize grain plantlets and the quality of stored tortillas at 4 and 28 °C. The most outstanding formulation was that based on 59.7% chitosan + 20% propolis nanoparticles + 20% pine resin extract nanoparticles; since the in vitro conidia germination of A. flavus did not occur, disease incidence on grains was 25-30% and in tortillas, 0% infection was recorded, along with low aflatoxin production (1.0 ppb). The grain germination and seedling growth were markedly reduced by the nanocoating application. The percentage weight loss and color of tortillas were more affected by this coating compared to the control, and the rollability fell within the scale of non-ruptured at 4 °C and partially ruptured at 28 °C. The next step is to evaluate the toxicity of this formulation.

Co-occurrence of aflatoxins in plant oil products from China.

Aflatoxins have been detected as contaminants of oil crops before harvesting and drying, during storage and manufacturing and could be transferable to plant oils. There are more than 20 different types of aflatoxins, among which the most commonly occurring are the B1, B2, G1 and G2. Concentrations of these four aflatoxins were determined in plant oils from retail shops in China and in crude peanut oil extracted from culled mouldy peanuts by HPLC with fluorescence detection. Overall, aflatoxins were present in 25 of the 63 samples. The four aflatoxins co-existed in vegetable oil, but the content of AFB1 was usually higher than the other aflatoxins. Particularly in the case of highly contaminated oil samples, AFB1 accounted for 68% of the total aflatoxins. According to the health risk assessment, the low margin of exposure values from AFB1 in oils suggests a high level of concern for children.

The presence and transfer characteristics of aflatoxins in medicinal herbs: From raw materials to edible dispensing granules.

In this study, a sensitive and accurate immunoaffinity columns coupled with high-performance liquid chromatography method was established to monitor the presence of aflatoxins-aflatoxin B1 , aflatoxin B2 , aflatoxin G1 , and aflatoxin G2 -in different medicinal herbs. The proposed method was found to be suitable for the detection of aflatoxins in eight kinds of herbs and their corresponding granules. Two batches of Arecae semen were positive for aflatoxins, with high residue levels of different aflatoxins. To better understand the presence and transfer of aflatoxins during the formulation of dispensing granules from the herbs, the aflatoxins-free herbs were artificially inoculated with Aspergillus flavus to explore aflatoxins production. Both aflatoxin B1 and aflatoxin B2 were detected in all inoculated samples, while aflatoxin G2 was only detected in Astragali radix samples. Additionally, the presence of aflatoxin B1 was extremely high compared to other aflatoxins. More specifically, the transfer rate of the aflatoxin B1 and the total aflatoxins from original herbs to granules were both approximately 40%. These findings indicated that the preparation of herbs into dispensing granules reduced the content of aflatoxins. The high-level presence of aflatoxins in inoculated herbs indicated that attention is needed to the safety of A. flavus-contaminated herbs.

Simultaneous Determination of Aflatoxins and Benzo(a)pyrene in Vegetable Oils Using Humic Acid-Bonded Silica SPE HPLC-PHRED-FLD.

In the present work, a rapid, accurate, and cost-effective method was developed for the simultaneous quantification of aflatoxins and benzo(a)pyrene in lipid matrices, using solid-phase extraction (SPE) via humic acid-bonded silica (HAS) sorbents, followed by high-performance liquid chromatography coupled with photochemical post-column reactor fluorescence spectroscopy (HPLC-PHRED-FLD) analysis. The major parameters of extraction efficiency and HPLC-PHRED-FLD analysis were investigated and this method was fully validated. The limits of quantification and the limits of detection were 0.05-0.30 and 0.01-0.09 µg kg-1, respectively. The recoveries were 66.9%-118.4% with intra-day and inter-day precision less than 7.2%. The results of 80 oil samples from supermarkets indicated a high occurrence of BaP, and most of concentrations were within the requirements of EU and China food safety regulations. This is the first utilization of HAS-SPE HPLC-PHRED-FLD to simultaneously analyze the occurrence of aflatoxins and benzo(a)pyrene in vegetable oils.