Forty silage samples were collected from Assiut and Sohag governorates in Egypt to measure the presence of fungal population in silage. Forty-three species and 2 species varieties belonging to 17 genera were isolated using glucose Czapek's and Sabouraud's dextrose agar media at 28 degrees C. The most prevalent genera were Aspergillus (57.5 and 100 of the samples), Penicillium (100 and 55%) on the two mentioned media, respectively. Also, Fusarium oxysporum and Gibberella fujikurori were recovered in moderate incidences. Mycotoxin profiles were also determined in these samples: Aflatoxins showed the highest incidence rates of occurrence, it occurred in 22.5% of all samples analyzed. Other mycotoxins were detected from all samples (T2 toxins and sterigmatocystin at incidence of 7.5 and 5%, respectively). The screening of the characteristics mycotoxins of different isolates of Aspergillus isolated from silage samples was tested. The results clarified that some mycotoxins (aflatoxins-aspergillic acid-beta nitro propionic acid-cyclopiazonic acid-kojic acid and sterigmatocystin) were produced by some isolates of A. flavus. Some isolates of A.fumigatus could produce gliotoxin and verrucologen. All of A. niger isolates tested were able to produce kojic acid. One isolate of A. ochraceous formed ochratoxin A and other isolate produced penicillic acid. Concerning A. terreus isolates, the results showed that 5 isolates were able to produce citrinin and 4 isolates had ability to produce patulin. A. versicolor isolates showed the ability to produce ochratoxin A.

γ-Linolenic acid (GLA) and carotenoids have attracted much interest due to their nutraceutical and pharmaceutical importance. Mucoromycota, typical oleaginous filamentous fungi, are known for their production of valuable essential fatty acids and carotenoids. In the present study, 81 fungal strains were isolated from different Egyptian localities, out of which 11 Mucoromycota were selected for further GLA and carotenoid investigation. Comparative analysis of total lipids by GC of selected isolates showed that GLA content was the highest in Rhizomucor pusillus AUMC 11616.A, Mucor circinelloides AUMC 6696.A, and M. hiemalis AUMC 6031 that represented 0.213, 0.211, and 0.20% of CDW, respectively. Carotenoid analysis of selected isolates by spectrophotometer demonstrated that the highest yield of total carotenoids (640 μg/g) was exhibited by M. hiemalis AUMC 6031 and M. hiemalis AUMC 6695, and these isolates were found to have a similar carotenoid profile with, β-carotene (65%), zeaxanthin (34%), astaxanthin, and canthaxanthin (5%) of total carotenoids. The total fatty acids of all tested isolates showed moderate antimicrobial activity against Staphylococcus aureus and Salmonella Typhi, and Penicillium chrysogenum. To the best of our knowledge, this is the first report on the highest yield of total lipid accumulation (51.74% CDW) by a new oleaginous fungal isolate R. pusillus AUMC 11616.A. A new scope for a further study on this strain will be established to optimize and improve its total lipids with high GLA production. So, R. pusillus AUMC 11616.A might be a potential candidate for industrial application.

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Increasing the pH from 5 to 9 decreased the toxicity of mercuric chloride, zinc sulfate, lead nitrate, copper sulfate and nickel chloride toward the growth of Aspergillus flavus, Penicillium chrysogenum, Cunninghamella echinulata, Myrothecium verrucaria and Phoma humicola. On the other hand, the toxicity of cadmium chloride was increased by the increasing pH. Also increasing the concentration of organic matter (peptone and yeast extract) from 0.5 to 1.5% induced a significant reduction in the toxicity of all heavy metals toward the growth of all test fungi.

Among Trichophyton spp. examined for urease production, T. rubrum was negative, whereas T. mentagrophytes appeared to be the most active species. Urease was not detected in cell-free culture fluids of the tested fungi. The endocellular urease of the test fungi was essentially constitutive. Moreover, addition of urea to the growth medium of these organisms markedly inhibited their mycelial biomass and ureolytic yield. Environmental factors showed variable effects on the test fungi and there was no correlation between mycelial growth and urease activity of these fungi.