Occurrence of Aspergillus spp. and aflatoxin B1 in Malaysian foods used for human consumption.

Malaysian population widely consumes the cereal-based foods, oilseeds, nuts, and spices in their daily diet. Mycotoxigenic fungi are well known to invade food products under storage conditions and produce mycotoxins that have threat to human and animal health. Therefore, determining toxigenic fungi and aflatoxin B(1) (AFB1) in foods used for human consumption is of prime importance to develop suitable management strategies and to minimize risk. Ninety-five food products marketed in Penang, Malaysia were randomly collected from different supermarkets and were analyzed for presence of Aspergillus spp. by agar plate assay and AFB1 by enzyme-linked immunosorbent assay (ELISA). A. flavus was the dominant fungi in all foods followed by A. niger. Fifty-five A. flavus strains were tested for their ability to produce aflatoxins on rice grain substrate. Thirty-six (65.4%) strains out of 55 produced AFB1 ranging from 1700 to 4400 µg/kg and 17 strains (31%) produced AFB2 ranging from 620 to 1670 µg/kg. Natural occurrence of AFB1 could be detected in 72.6% food products ranging from 0.54 to 15.33 µg/kg with a mean of 1.95 µg/kg. Maximum AFB1 levels were detected in peanut products ranging from 1.47 to 15.33 µg/kg. AFB1 levels detected in all food products were below the Malaysian permissible limits (<35 µg/kg). Aspergillus spp. and AFB1 was not detected in any cookies tested. Although this survey was not comprehensive, it provides valuable information on aflatoxin levels in foods marketed in Malaysia.

Occurrence of Fusarium spp. and fumonisins in stored wheat grains marketed in Iran.

Wheat grains are well known to be invaded by Fusarium spp. under field and storage conditions and contaminated with fumonisins. Therefore, determining Fusarium spp. and fumonisins in wheat grains is of prime importance to develop suitable management strategies and to minimize risk. Eighty-two stored wheat samples produced in Iran were collected from various supermarkets and tested for the presence of Fusarium spp. by agar plate assay and fumonisins by HPLC. A total of 386 Fusarium strains were isolated and identified through morphological characteristics. All these strains belonged to F. culmorum, F. graminearum, F. proliferatum and F.verticillioides. Of the Fusarium species, F. graminearum was the most prevalent species, followed by F. verticillioides, F. proliferatum and then F. culmorum. Natural occurrence of fumonisin B1 (FB1) could be detected in 56 (68.2%) samples ranging from 15-155 µg/kg, fumonisin B2 (FB2) in 35 (42.6%) samples ranging from 12-86 µg/kg and fumonisin B3 (FB3) in 26 (31.7%) samples ranging from 13-64 µg/kg. The highest FB1 levels were detected in samples from Eilam (up to 155 µg/kg) and FB2 and FB3 in samples from Gilan Gharb (up to 86 µg/kg and 64 µg/kg).