Validation of PCR based detection system for aflatoxin producing molds

Abstract

Aflatoxins are polyketide secondary metabolites that are produced by certain fungal species in the Aspergillus section Flavi, particularly Aspergillus flavus and Aspergillus parasiticus which contaminate human food as well as animal feed. These are among the most carcinogenic substances known. Due to the toxic and carcinogenic properties of aflatoxins, there is a need to develop reliable methods to detect the presence of aflatoxigenic Aspergilli in contaminated food and feed. Not all Aspergillus strains are able to produce aflatoxins. It requires a detection methodology which can specifically distinguish between the aflatoxin producing and non-producing strains of Aspergillus. Present communication reports validation of a PCR based detection system based on three genes viz., nor-1, apa-2 and omt-1 involved in aflatoxin biosynthesis, that can specifically distinguish the two aflatoxin producing species viz. Aspergillus flavus and Aspergillus parasiticus from non-producers i.e., A. niger, A. fumigates and A. oryzae.