Endophytes are bacterial or fungal microorganisms that colonize healthy plant tissue intercellularly and/or intracellularly without causing any apparent symptoms of disease. In this study, the ethyl acetate extract of endophytic fungi associated with some medicinal plants such as Eugenia caryophyllus and Mentha spicata L, was investigated for its antimicrobial, and antioxidant potentials. Antimicrobial potential was evaluated by disc diffusion method against 12 pathogenic bacteria and one fungal strain. The antioxidant potential was determined via 1, 1-diphenyl-2- picrylhydrazyl (DPPH) assay. The ethyl acetate extract of the isolated endophytic fungi Penicillium chrysogenum, Aspergillus flavus, and Aspergillus niger showed significant antimicrobial activity against both Gram-positive bacteria (Staphylococcus aureus, Staphylococcus epidermidis, Bacillus subtilis) and Gram-negative bacteria (Klebsiella pneumonia). However, both Penicillium chrysogenum and Aspergillus niger extracts showed equipotent or better antioxidant activity when compared to ascorbic acid with IC50 = 12.22, 13.4 vs. 13.30 mg/ml for ascorbic acid. Fractionation and phytochemistry screening for Penicillium chrysogenum extract revealed that the major active compounds reside in the organic fraction neither in aqueous nor in mycelia extract. The ethyl acetate extract was further subjected to thin layer chromatography (TLC) and gas chromatography mass spectroscopy (GC-MS) analyses which disclosed 13 different compounds with n-hexadecanol, phthalic acid-2-propylpentyl ester, and n-heptadecanol as the major components. However, full and detailed investigation to identify and characterize the major compounds is currently under progress. The obtained results showed that the endophytic fungus could be considered as a potential source of antioxidant and antimicrobial compounds.
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