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Fusarium mycotoxins contaminated in maize are of serious threat to food security and safety. The main abiotic factors of mycotoxins-producing strains and circumstantial elements are crucial for mycotoxin production in the cereal matrix. In this current research work, Fusarium verticillioides and Fusarium graminearum are selected, which enable to produce the major mycotoxins in maize as common Fusarium isolates infecting maize. We first confirmed the constitution of mycotoxin profiles in 110 maize and derived feed samples collected from various provinces of China, through large-scale screening by the established high performance liquid chromatography-mass spectrometry (LC-MS/MS) approach. As indicated, the majority of mycotoxins was fumonisin, deoxynivalenol and zearalenone, frequently co-occurred with at least two kinds of mycotoxins. Interestingly, zearalenone-14-sulfate together with other masked forms of the target Fusarium mycotoxins were as co-contaminants there. Moreover, the circumstantial effects from a set of temperature and water activity (aw) are thoroughly demonstrated for potential contamination in maize flour and kernels. As revealed, the highest group factors were 0.99 and 25 °C while the relatively lower group factors were of temperature ≤20 °C or aw ≤ 0.95. Finally, a response surface analysis was performed to display the interaction of temperature-water activity interaction, required for potential contamination of Fusarium mycotoxins in maize and derived products. The risk group factors predicted by response surface equation were similar to the experimental results. This also could be valuable clues for pre-warning of mycotoxins occurrence, thus as reference data for control of mycotoxins in foods.

In this work, based on a newly obtained monoclonal antibody (MAb) against zearalenone (ZEN) and biotin–streptavidin system (BSAS) for signal amplification, two sensitive and rapid immunoassay formats including biotin–streptavidin amplified enzyme-linked immunosorbent assay (BA-ELISA) and biotin–streptavidin amplified fluorescence-linked immunosorbent assay (BA-FLISA), were developed for family zearalenones (ZENs) determination. And the limits of detection (LODs) of ZEN were 0.02 ng mL−1 and 0.10 ng mL−1 for BA-ELISA and BA-FLISA respectively. Using the BA-ELISA platform the half maximal inhibitory concentrations (IC50) were 0.18 ng mL−1 for ZEN, 0.39 ng mL−1 for α-zearalenol (α-ZOL), 0.46 ng mL−1 for β-zearalenol (β-ZOL), 0.30 ng mL−1 for zearalanone (ZAN), 0.30 ng mL−1 for α-zearalanol (α-ZAL), and 0.73 ng mL−1 for β-zearalanol (β-ZAL). With the broad specificity, the developed immunoassays could be used as sensitive and valuable tools for detection of family ZENs. Additionally, the suitability of the proposed immunoassays for its application to corn flour and corn based baby food has also been investigated.

The primary objective of this study was to synthesize three types of cross-linked chitosan polymers and further investigate their adsorption capability for multiple mycotoxins, including aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN), fumonisin B1 (FB1), deoxynivalenol (DON) and T-2 toxin (T2). Among these synthetic adsorbents, cross-linked chitosan-glutaraldehyde complex presented the highest adsorption capability for AFB1 (73%), OTA (97%), ZEN (94%) and FB1 (99%), but no obvious adsorption for DON and T2 ( 0.98), with the predicted maximum adsorption amounts were 24.8 mg/g for OTA and 9.18 mg/g for ZEN. In addition, the adsorption capability of adsorbent for the simultaneous presence of multiple mycotoxins was also evaluated in buffer system and simulated gastrointestinal condition. The results indicated that the coexisted multiple mycotoxins didn't affected the adsorption capability of adsorbent, whereas the adsorption amounts of toxins were decreased by some gastrointestinal components. The findings of this research suggest that chitosan–glutaraldehyde complex has the potential to be applied as multitoxin adsorbent material for reducing the combined adverse effect of multiple mycotoxins on humans and animals.

The co-occurrence of food contaminants has caught the public concern worldwide owing to their extensive distribution and the potential risk on human health. In this study, a total of 6471 samples of cereals and cereal-based products was collected from Shanghai between 2008 and 2011. The food contaminants co-occurred, including mycotoxins (aflatoxin B1, deoxynivalenol and ochratoxin A), pesticides (organic phosphorus pesticides and methyl bromide), heavy metals (cadmium, lead, and inorganic arsenic), and food additives (aluminum and food pigments), were analyzed for their contents. The point evaluation and probabilistic evaluation based on the Monte Carlo model were performed to assess the risks of the contaminants. The results showed the mean levels of all the tested contaminants were lower than the maximum residue levels (MRLs) set by China, except aluminum, exceeding China MRLs of 100 mg/kg in 2010 and 2011. The point evaluation showed the mean daily exposures (40.7–63.9 ng/kg bw/day) of ochratoxin A in 2010 for different consumer groups were higher than the provisional tolerable daily intake (PTDI) of 17 ng/kg bw/day recommended by the European Food Safety Authority (EFSA). Meanwhile, the mean daily exposures of the tested contaminants in each year for 7-to-10-year old children were higher than those for adults. The probabilistic evaluation indicated that the margin of safety (MOS) values of the tested contaminants at percentile 95th (P95) were lower than 1, except aluminum, suggesting the potential health risk of aluminum intake to the consumer groups in Shanghai. Additionally, the risk ranking of these contaminants in cereals and cereal-based products was obtained as follows: aluminum > deoxynivalenol > ochratoxin A > inorganic arsenic > cadmium > lead > chlorpyrifos-methyl > malathion.

The contamination of food with Aspergillus flavus and subsequent aflatoxins is considered as one of the most severe safety problems in the world. The application of microorganisms and the produced bio-active compounds is considered as the most promising method for controlling foodborne pathogens and mycotoxins contamination both in pre- and post-harvest. Vt-7, identified as Enterobacter asburiae, was able to completely inhibit the growth of Aspergillus flavus (AF) and other seven important fungal pathogens by the production of volatiles. Additionally, it can also significantly inhibited AF infection on peanuts in storage, down-regulated the gene expression of aflatoxin biosynthesis and eventually prevented aflatoxins production. Scanning electron microscope further proved that Vt-7 volatiles prevented conidia germination of AF on peanut surface, and severely destroyed the conidia structure. Gas chromatography – tandem mass spectrometry revealed that two abundant compounds (1-Pentanol and Phenylethyl Alcohol) were involved in the volatile profiles. They showed great antagonistic activity against AF with minimal inhibitory concentration at 200 μL/L. Therefore, E. asburiae Vt-7, and volatiles 1-Pentanol and Phenylethyl Alcohol were effective agents in controlling AF and aflatoxins in peanut during storage. They will provide novel strategies for the application of microbe and bio-active compounds against fungal pathogens and mycotoxins in food and grains during storage.

Selenium nanoparticles (SNP) were generally utilized as chemotherapeutic agents and environmental ameliorants, but without simultaneous biocontrol functionalities against fungal pathogens and mycotoxins, plus unknown recognition mechanism. Selenium nanoparticles derived from Trichoderma harzianum JF309 (TSNP) were herein synthesized, contrast to traditional SNP, where diverse metabolites co-occurred in TSNP including organic acids and their derivates, such as psoromic acid, β-decyloxybenzoic acid, glucaric acid lactone, etc., revealed by Triple TOF UPLC/HRMS. As hypothesized, this interaction of diverse recognition metabolites and selenium nanoparticles in TSNP might change the arrangement and movement of original state, form random, nondirective to regulated, directional, thus contributing to better antifungal effects and dramatically increasing control functionalities against Alternaria toxins (83% of TeA and 79% of AOH reduction), fumonisin B1 (63% of FB1 reduction) and deoxynivalenol (76% of DON reduction), respectively. Meanwhile, expression of key biosynthetic genes of FUM1, PA, TRI5 and TRI6 were substantially decreased. Finally, as convinced, the obtained nanoparticles had no significant side effects to the selected three human cells. In total, the achieved data supports the biogenic nanoparticles as valuable functional materials with great potential for practical plant protection and food safety prevention.

Mycotoxin ochratoxin A (OTA) is considered to be a possible risk factor for adverse effects in humans. In the present study, quantitative assessment of risk associated with dietary intake of OTA was performed based on consumption habits of the representative adult inhabitants in Shanghai city of P. R. China. Firstly, a total of 400 food samples randomly collected from different locations of Shanghai were analyzed by the previously established isotope dilution LC–MS/MS method. Then, 265 participants of 70 males and 195 females as representative inhabitants were invited to answer the designed questionnaire about the quantity and frequency of foods including four major varieties of grapes, cereals, beans and dried fruits as well as their derived products. Finally, all data were simulated by the point evaluation and model evaluation for the risk assessment of OTA contamination. Results from the point evaluation indicated that mean value of daily intake (DI) of OTA was 1.147 ng/kg body weight/day, which was lower than all the reference standards. However, DI value (8.566 ng/kg body weight/day) in the high percentile (97.5th) was obviously higher than the PTDI (5 ng/kg body weight/day) proposed by Scientific Committee on Food. Among the different groups of foods, OTA in cereals and derived products made the largest contribution to the potential healthy risk. The mean DI value and 97.5th percentile were 1.093 and 7.962 ng/kg body weight/day, respectively, indicating that more than 90% of the risk was due to the contamination of OTA in cereals and derived products. On the other hand, similar results were obtained by the Monte Carlo assessment model. Thus, from the currently available data and analyzed results on the adult inhabitants, regarding OTA contamination issues on food safety administration of Shanghai, there was no significant attention which should be paid on food consumption in Shanghai, besides cereals and derived products with very little possibility as the risk factors.

A lateral flow immunoassay (LFA) for rapid and sensitive quantitation of zearalenone (ZEN) in food and feed stuffs was developed, based on the availability of a new highly sensitive anti-ZEN monoclonal antibody. Compared to previously reported LFA, the established method allows quantitative determination of ZEN within the desirable dynamic range of 1–50 ng mL−1, corresponding to the recorded color intensity (CI) values of 65–9, with an IC50 value of 15 ng mL−1. The developed approach was then applied to a sample collection of thirty two cereal-based baby food, maize, wheat and feed samples, revealing that seven positive samples contained ZEN at concentrations ranging from 20 to 94 μg kg−1. The accuracy of the obtained results was confirmed by in-parallel LC–MS/MS analyses. The described assay format is capable of simple, rapid, cost-effective and robust on-site screening or remote quantitative analysis for ZEN, fulfilling the currently strictest regulation requirements for ZEN monitoring worldwide.