Chika C Abba, Ogechi O Anyanwu, Somtochukwu R Ewuzie, Chukwubuikem C Okolo, Blessing O Umeokoli, Ugochukwu M Okezie and Ike V Ezenwa

Attention is being diverted towards the bioprospecting of newer bioactive constituents from marine endophytic fungi. Marine fungi have shown a large chemo-diversity of untapped important secondary metabolites needed for drug discovery and development. In this present study, secondary metabolites were isolated from the endophytic fungi from leaves of a marine plant, Acioa barteri. The fungal isolation, taxonomic identification, fermentation, extraction and isolation of the fungal secondary metabolites were carried out using standard techniques. The crude extracts of the three asperigious species were screened for antimicrobial and antioxidant assays. Antimicrobial and antioxidant activities were assessed using agar diffusion; 1, 1 -diphenyl-2- picrylhydrazil (DPPH); Ferric reducing antioxidant power (FRAP); and nitric oxide scavenging assays. The active extracts exhibited good antimicrobial activities against P. aeruginosa, S. aureus, E. coli, B. subtilis, C. albicans and A. niger with an inhibition zone diameter (IZD) that ranged from 2mm, 2.5mm, 2mm, 2mm, 4mm, 2mm respectively for Ab1 extract. The Gram negatives; P. aeruginosa, S. aureus were the most susceptible bacteria while C. albicans was the most susceptible fungi. Moderately low antioxidant activities were recorded in the DPPH and FRAP assays of the three plant fungi isolates and also the lower the 1C_50, for DPPH and nitric oxide assay and EC₅₀ for FRAP, the more the antioxidant activity? From the study, the endophytic fungi isolated from the leaf of Acioa barteri possess moderate antimicrobial and antioxidant activities when compared to the standards. The higher the concentration, the higher the activity; hence, it was dose dependent. The outcome of the study justifies the use of this plant in ethnomedicinal therapeutics.

Pages: 405-412  |  584 Views  222 Downloads