Isolation, identification of some fugal isolates and testing their ability for lipoxygenase production

Eighty three local isolates of fungi were isolated from different resources (Peanuts , maize, rice, wheat, bread, domestic cheese of sheep, Milk local Cream, Iranian cream, Roquefort cheese and soil). These isolates were purified and identified, it include 14 isolates of Aspergillus flavus, 13 Aspergillus niger,8 Aspergillus terreus,3Aspergillus parasaticus,3Alternaria spp.,15Penicilliumspp.,7Fusarium spp.,5 Trichoderma spp., 11 Rhizopus spp. and 7Mucor spp. The ability of isolates for producing aflatoxin were tested, the toxic isolates(Aspergillus flavus,Aspergillus terreus ,and Aspergillus parasaticus) were removed.Aspergillus niger which was isolated from maize was choosing as the best lipoxygenase producer after Primary and secondary screening. The growth of the selected isolate colonies had the largest proportion than the Colonies of Penicillium sp. and Trichoderma sp..all so the same isolate had high enzymatic activity 801.4units/ml, while Penicillium sp. and Trichoderma sp. had (559.2 and 120) units/ml respectively.