Detection of aflatoxins by HPLC and the expression of biosynthetic nor-1 gene of aflatoxin and ocrA gene of ochratoxin

Document Type : Original Article

Authors

1 Bacteriology, Mycology and Immunity Department, Faculty of Veterinary Medicine, Zagazig University, Egypt

2 Microbiology Department, Faculty of Science, Zagazig University, Egypt

Abstract

Due to the high toxicity of aflatoxins and its effects on public health and animal wealth, food and feed.
The determination of mycotoxins in commodities is the only way of control. The identification of
aflatoxigenic Aspergillus isolates through detection of nor-1 gene was tried. Ochratoxin has been widely
detected in cereal-derived products. Its production by A. ochraceous and its biosynthetic gene ocrA was
evaluated. For this purpose, 500 different cereal samples were collected from different markets in
Sharkia Province. Five strains of Aspergillus spp. have been screened for their ability to produce
aflatoxins after cultivation in Czapek,s Dox media. Aflatoxin B1was detected in average amount 4.9-
200 ng/μl through using HPLC technique. A Real time PCR (RT-PCR) technique was applied to
determine the gene expression of structural nor-1, which catalyzed the first step in aflatoxins
biosynthetic pathway

Keywords