Determination of Mycoflora and Mycotoxins in Raw and Roasted Peanuts in Bangladesh

Abstract

Mycoflora and mycotoxin contamination are major challenges in peanut (Arachis hypogaea L.) production, trading and health concern to humans and animals. A total of 24 peanut samples out of which 12 were raw and 12 were roasted; were collected from different places in Bangladesh. These samples were examined for detection of mycoflora and mycotoxin. The mycoflora associated with the peanuts belonged to 11 fungal genera such as Aspergillus, Alternaria, Chaetomium, Cladosporium, Curvularia, Fusarium, Mucor, Penicillium, Pestalotia, Rhizopus and Trichoderma and frequencies of occurrence ranged from 0.33% to 71.95%. Aspergillus (71.95%) was the most dominant while the least was Trichoderma (0.33%). The fungal genus Aspergillus was found to be the most occurred (5501 colonies) and Pestalotia was the least occurred (25 colonies) pathogen in all samples. The highest number of fungal colonies (393) were formed in raw peanut collected from Sadarpur, Faridpur, however, the lowest number of fungal colonies (232) were formed in raw peanut collected from Potuakhali. Aspergillus was available in all the 24 samples. Penicllium was present in 12 raw peanut samples; on the other hand, Rhizopus was present in 12 samples of roasted peanuts. Aflatoxins were detected from 5 raw samples and 3 roasted samples and detection level of total aflatoxin ranged from 1.72 to 8.52 μg kg-1. The highest level of aflatoxin (8.52 μg kg-1) was detected in raw peanuts from Sibchor, Madaripur. Maximum amount of total aflatoxin among the roasted peanut was 6.71 μg kg-1 collected from Chorvodrasan, Faridpur district of Bangladesh. Finding of this study would help us in planning strategies for awareness and management of aflatoxin.