Reduction of aflatoxins by Rhizopus oryzae and Trichoderma reesei.

Abstract

This study evaluated the ability of the microorganisms Rhizopus oryzae (CCT7560) and Trichoderma reesei (QM9414), producers of generally recognized as safe (GRAS) enzymes, to reduce the level of aflatoxins B1, B2, G1, G2, and M1. The variables considered to the screening were the initial number of spores in the inoculum and the culture time. The culture was conducted in contaminated 4% potato dextrose agar (PDA) medium, and the residual mycotoxins were determined every 24h by HPLC-FL. The fungus R. oryzae has reduced aflatoxins B1, B2, and G1 in the 96h and aflatoxins M1 and G2 in the range of 120h of culture by approximately 100%. The fungus T. reesei has reduced aflatoxins B1, B2, and M1 in the 96h and aflatoxin G1 in the range of 120h of culture by approximately 100%. The highest reduction occurred in the middle of R. oryzae culture.