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Propolis was responsible for in vitro growth suppression of some tested phytopathogenic fungi. Four tested species were partially inhibited by using propanolic or ethanolic extract associated with promising growth reduction of Fusarium oxysporum in a per cent of growth recorded 38.2% or 58.9% during propanolic or ethanolic application, respectively, while Helminthosporium sp. and Cladosporium sp. showed unexpected activation of growth during propanolic or ethanolic extract applications. The antimicrobial products identified during GC-MS analysis of the propolis propanolic extract were Pyrazole, Quinic acid, D-lactic acid, Pentanoic acid, Erythritol and sulfonamide derivatives. The SDS gel electrophoresis of soluble proteins of Fusarium oxysporum treated with propanolic or ethanolic propolis extracts showed a specific protein band at 26.002 kDa with the untreated pathogen, and several characterized bands at 21.160, 26.012, 28.666, 38.44, 102 kDa related to propolis propanolic extract (2) and finally a two markedly visible bands at 18.871, 33.083 kDa with propolis ethanolic extract (3). The decrease in enzyme activity of cellulase and pectinase of Fusarium oxysporum was recorded under treatment with either propanolic or ethanolic extracts. There was suppression in the degree of infectivity such as the number of rotted seeds, wilting, brown discoloration of Phaseolus seedlings presoaked in either of the two propolis extracts compared to infected plants with more reduction individually in case of propanolic extract over that of ethanolic one.

AN AGRICULTURAL soil was used to isolate Alternaria alternata. It was molecularly identified and was given an accession number MN645469 at the National Center for Biotechnology Information (NCBI) and a strain identifier to be Alternaria alternata strain NMK1. Four fractions were collected from the acetic acid extract of its filtrate. Fraction no. 2 showed highest antioxidant activity (71 and 64%, at 200 and 150μg/mL) followed by the crude extract (60 % at 200μg/mL). Safety of using the extracted fractions was tested against the normal human amnion (WISH) cell line. Lowest cytotoxicity values were recorded for fraction no. 2 (19%) followed by the crude extract (28%) at 50μg/mL. Aspergillus flavus, Aspergillus niger and Penicillium griseofulvum exhibited highest relative density percentages (28.4, 30.8 and 24.3%) on their respective isolation seeds; wheat, broad bean and kidney bean. Interestingly, fraction no. 2 caused 100% inhibition of these isolated fungal species at 100μg/mL. The minimum fungicidal concentration (MFC) was estimated to be 50μg/mL against A. flavus and 40μg/mL for A. niger and P. griseofulvum. Generally, subjecting each of the tested isolates to fraction no. 2 led to damage in their DNA as shown by the comet assay. Gas chromatography- mass spectroscopy (GC-MS) profiling of fraction no. 2 showed 12 major compounds with diverse possible biological activities being antiinflammatory, insecticide, anticancer, antineoplastic antifungal, and antimicrobial.

TWENTY FIVE Aspergillus isolates were screened from Giza Governorate and Saint Catherine Protectorate soils in Egypt. The antimicrobial activity of the crude extracts was tested against two Gram positive bacteria (Bacillus subtilis NRRL-B-4219, Staphylococcus aureus ATCC29213), four Gram negative bacteria (Alcaligenes faecalis B-170, Escherichia coli ATCC25922, Klebsiella pneumoniae ATCC10131, Pseudomonas aeruginosa ATCC27953), and one yeast (Candida albicans ATCC10231). The antioxidant activity using free radical scavenging model was assayed for the crude extracts. The antitumor activity for all of crude extracts was determined against HCT116 (Colon carcinoma cell line), HEPG2 (Liver carcinoma cell line), and MCF-7 (Breast carcinoma cell line). Aspergillus nomius was the most potent fungal species accordingly, it was chosen for bioactivity assay. Identification of this species was further confirmed at the molecular level based on nuclear ribosomal DNA 18s identities. An accession number, LC199488, was given at the DDBJ GenBank. The column chromatography of its crude extract yielded five distinguished fractions. The biological (antimicrobial, antioxidant and antitumor) activities of these fractions were assayed. Fraction B proved to be of most potential. HPLC analysis of this fraction showed that there was a sharp and clear peak at about 18.1 min. This denoted the presence of an active compound. The compound at this peak was purified and its structure was elucidated via 1HNMR and 13CNMR spectroscopy. It was concluded that it would be 1,2,3,9 tetrahydropyrrolo [2,1-b] quinazolin-3-ol.

THIS STUDY aimed at investigating the effect of gamma irradiation…… on the phenotypic characters of Aspergillus niger and its impacton the activities of some enzymes such as lipase, protease, cellulase,pectinase and amylase. Two phenotypically different mutants wereobtained after gamma irradiation at doses of 1 and 3 kGy. SEMmicroscopy showed clear morphological changes in conidiophores,conidial heads and spores among all strains. The activities of lipase,protease and cellulase in both mutants become less than that of theparent strain, while, pectinase showed no significant difference amongthe tested strains. Amylase activity was enhanced by gammairradiationin the mutants. The obtained mutants were molecularlycharacterized using RAPD-PCR. The results demonstrated theoccurrence of polymorphic pattern between parent and mutant strainsdue to change in the genetic makeup.

THE MAIN concept of this study was to assess the potentiality of hydrolytic enzymes as virulence factors for Aspergillus species during aspergillosis infection process. Forty Aspergillus species were isolated from medical (15 isolates) as well as environmental isolates (25 isolates) from soils, outdoor and indoor environments. Extracellular proteases, phospholipases and esterase activities were measured. The pathogenicity of some Aspergillus species was in vivo assessed. It was represented in mean survival times, mortality percentages, fungal counts in different organs, and histopathological examination of lung tissue. The expression levels of protease, phospholipase and esterase genes were studied by real time PCR. Four physiologically significant isolates were selected out of forty and were identified up to molecular level. Aspergillus ochraceus fm90 recorded the highest pathogenicity as represented by mortality percentages and mean survival times of mice, while A. flavus fm90 was the least pathogenic one. Expression of genes of protease, phospholipase and esterase was found to be greater in A. ochraceus fm90 than in A. flavus fm90. It can be concluded that pathogenicity is probably related to physiological (enzymatic) activities of the isolates. Also, variation in expression levels of protease and phospholipase genes in A. ochraceus fm90 and A. flavus fm90 could denote their possible involvement in the pathogenicity process.