BIOLOGICALLY ACTIVE METABOLITES OF AN ENDOPHYTIC FUNGUS ISOLATED FROM VERNONIA AMYGDALINA
Okezie UM1, Eze PM1*, Okoye FBC2*, Ikegbunam MN1, Ugwu MC1, Esimone CO1
1 Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka-Nigeria
2 Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Awka-Nigeria
Afr. J Pharm Res Dev; Volume 9(1): 24-29; June/July 2017
ABSTRACT
An endophytic fungus was isolated from the leaves of Vernonia amygdalina. The fungus was subjected to solid state fermentation on rice medium and the metabolites were extracted using ethyl acetate. The fungal extract was screened for antimicrobial activity and the bioactive compounds of the extract were detected using high-performance liquid chromatography-diode-array detection (HPLC-DAD) analysis. The antimicrobial assay was carried out using agar diffusion assay method against Staphylococcus aureus, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Entorococcus faecalis, Aspergillus niger and Candida albicans. The fungal extract, at a concentration of 1 mg/mL, inhibited all test bacteria except S. aureus. No antifungal activity was recorded against A. niger and C. albicans. The HPLC-DAD analysis of the extract revealed the presence of four bioactive compounds 4-hydroxyphenyl acetic acid, p-methoxycoumaric acid, indole-3-acetic acid, and acropyrone. 4-hydroxyphenyl acetic acid, which is a known antimicrobial agent, was the most abundant compound in the extract. Results of this study suggest that endophytic fungi associated with V. amygdalina could be a promising source of novel antimicrobial compounds.
KEYWORDS: Vernonia amygdalina, Endophytic fungi, Secondary metabolites, Antimicrobial activity, HPLC-DAD Analysis.
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