Isolation and Identification of Fungal Species in Kurdish Walnut Morphologically and using some Molecular Technique.

Abstract

Walnuts are world widely consumed in many local dishes in southeast Asian countries, especially in Iraq-Kurdistan-Tawella which is one of the major walnut cultivars area in this region, particularly in Hawraman region. Three species of filamentous fungi Asperagillus were identified in this study including A. niger, A. flavus, A. parasiticus and in walnut product including (salted walnut). Therefore, Aspergillus species, which produced a significant amount of aflatoxin, ochratoxin and T2- toxin contamination in walnuts during storage are becoming major concerns due to the insufficient condition that favors the growth of aflatoxigenic and ochratoxigenic fungi. The current study thus aimed to morphologically and molecularly identify and characterize the A. niger, A. Flavi, A. parasiticus isolated from Kurdish walnuts and its product. The DNA isolation from all fungal species wee r from agar cultures after inoculating and purifying for more times by using commercial kit (Bio basic INC kit). Agarose gel electrophoresis fractionation of the fungi DNA, showed clear individual bands. A. niger distinct band is 500 bp, A. flavus and A. parasiticus distinct band is 1032 bp. ELISA technique was applied for detection quantitatively for aflatoxin, ochratoxin and T2 toxin in Kurdish walnut. As stated in table two the result of ELISA method used for quantitative detection of aflatoxin, ochratoxin and T2 toxin is 5.9, 10.4 and 129 part per billion ppb respectively, it is safety range for all toxins.