TITLE:
A Novel Non Radioactive PCR-DNA Probe for the Detection of Aflatoxin Producing Aspergillus Species from Major Food Crops Grown in India
AUTHORS:
S. R. Priyanka, M. Venkata Ramana, K. Balakrishna, H. S. Murali, H. V. Batra
KEYWORDS:
AFB1-Aflatoxin B1; HPLC-High Performance Liquid Chromatography; NOR-1; Norsolorinic Acid Synthase; PCR-Polymerase Chain Reaction
JOURNAL NAME:
Advances in Microbiology,
Vol.2 No.4,
December
28,
2012
ABSTRACT: In the present study, a novel non radioactive digoxigenen labelled PCR-DNA probe was developed targeting nor-1 gene to assess the contamination of aflatoxigenic Aspergillus species in food grain samples from Southern parts of India. The sensitivity of developed PCR-DNA probe was determined to be 10 pg of genomic DNA and 1 pg of purified PCR product. The specificity of the DNA probe was validated by testing against an array of Aspergillus, Fusarium and Penicillium spp. A total of 89 Aspergillus isolates were recovered from 152 grain samples of maize, paddy, and groundnut. Among them, maize had the highest (90%) incidence of toxigenic Aspergillus species. When developed PCR-DNA probe was evaluated onto pure cultures of toxigenic and nontoxigenic Aspergillus species, 60 samples were positive for the nor-1 gene probe. DNA probe results unequivocally matched with the HPLC analysis. In conclusion, the novel PCR-DNA probe developed in this study may find its application in rapid detection of aflatoxin-producing Aspergillus isolates from contaminated cereal grains.