ENZYMES AND TOXINS PRODUCED BY FUNGI ISOLATED FROM MILK AND MILK PRODUCTS IN ASSIUT, EGYPT.

doi:10.21608/aunj.2018.221294

ENZYMES AND TOXINS PRODUCED BY FUNGI ISOLATED FROM MILK AND MILK PRODUCTS IN ASSIUT, EGYPT.

Document Type : Novel Research Articles

10.21608/aunj.2018.221294

Abstract

A total of 102 fungal strains obtained from fresh cow and buffalo milk as well as from yoghurt, kareish cheese and soft cheese were screened from their abilities to produce proteolytic and lipolytic enzymes. The tested strains comprised 52 yeasts and 50 filamentous fungi. The most active producers of both lipases and proteases were Candida paragosa, C. zeylanoides, Cryptococcus curvatus, Fusarium oxysporum (from baffalo milk), Magnesiomyces capitatus, Trichosporon jirovecii (from cow milk), Candida tropicalis, Geotrichum candidum, Lecythophora sp., Pichia kudriavzevii, Aspergillus flavus (from kareish cheese), P. cactophila, T. insectorum and Yarrowia lipolytica (from soft cheese), A. niger and Fusarium verticillioides (from yoghurt). Among the 50 mold strains tested for mycotoxin production in broth cultures 30 (60%) proved to be toxinogenic. Aflatoxins B1and G1 were detected in cultures of A. flavus (17 strains) and A. parasiticus (4 strains) obtained from various samples of milk and milk products. Sterigmatocystin was produced by 5 strains of A. nidulans. Fumonisin and zearalinone were detected in cultures of F. verticilliodes and F. oxysporum, respectively.

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