Control of different mycotoxins in food and feeds by Trametes versicolor and Lentinula edodes extracellular glucan oligomers

Different mycotoxins are usually biosynthesised during the morphological differentiation and the late phase of growth. Among them, ochratoxin A (OTA), patulin and aflatoxins represent a small but significant group produced for instance by Aspergillus ochraceus, Penicillium expansum and Aspergillus parasiticus as well A. flavus respectively. It was evidenced by many authors that cellular or environmental oxidative stress can represent a trigger, at least in Aspergillus flavus, A. parasiticus A. nidulans and Fusarium graminearum zearalenone and deoxynivalenol producer to induce the biosynthesis of different mycotoxins. From this scenario emerges that oxidative stress could represent a common trait in the formation of some mycotoxins. The activation of stress-related transcription factors such as yap 1 gene, perceiving oxidative stress in the fungal cell, triggers the synthesis of antioxidant-related enzymes modulating aflatoxins and OTA biosynthesis. -glucans and glycoproteins from the basidiomycetes Trametes versicolor and Lentinula edodes are able to stimulate yap 1 gene expression and to enhance the activity of the immune and antioxidant system in humans. The effect of -glucans on the inhibition of aflatoxin biosynthesis through the stimulation of antioxidant system (superoxide dismutase, catalase, glutathione peroxidase) of the fungal cells is evidenced. The results obtained are promising to control carcinogenic compounds such as mycotoxins in food and can constitute a safe tool to protect human and animal health by the use of “healing mushrooms”.