ANTIOXIDANT AND ANTIMICROBIAL ACTIVITIES OF ENDOPHYTIC FUNGI FROM FENNEL (Foeniculum vulgare Mill.) LEAF AND SEED

Abstract

Antioxidant and antimicrobial properties are the biological activity of natural compoundsisolated from medicinal plants that are rich source of novel drugs. Endophytic fungi are a potential source of novel bioactive compounds. The present study investigates antimicrobial and antioxidant properties of endophytic fungi from fennel (Insilali) seeds and leaves. The antioxidant activity was conducted based on determination of phenolic content, 1, 1-diphenyl-2-picrylhydrazyl and hydrogen peroxide free radical scavenging activities. The antimicrobial experiment was designed as six endophytic fungal extracts from leaf and seed of fennel at three concentration levels; a solvent; 4 test pathogens in a completely randomized factorial design in three replications. The result of total phenolic content, and DPPHradical scavenginging activity were found to be significantly the highest for Candida sp extract with phenolic content (8.76mg/L) and DPPH (66.10%), followed by Cladosporium ep extract with phenolic content (8.50mg/L and DPPH (55.99%). The antibacterial activity of the highest concentration of the extract (200mg/L) of the crude extracts has recorded mean zone of inhibition ranging from 14.50 to 24.53mm against both gram positive and gram negative bacterial test pathogens. Cladosporium sp extract presented the strongest antibacterial activity with maximum zone of inhibition (24.53mm) with the highest concentration (200mg/ml) of the fungal extract against S. aureus indicating that S. aureus is more susceptible to the crude endophytic fungal extracts than E. coli. The antifungal activity of the highest concentration of the extract (200mg/L) has presented the mean zone of inhibition ranging from 12.50 to 21.40mm. The maximum zone of inhibition 21.40mm was recorded for Cladosporium sp extract against A. versicolor. The endophytic fungal extract presented the strongest antibacterial activity with MIC (1.56mg/ml) and corresponding MBC (1.56mg/ml) for Cladosporium sp methanolic extract against S. aureus. As the weakest antibacterial activity with MIC (75mg/ml) and corresponding MBC (150mg/mg) were recorded for Aspergillus sp and Alternaria sp extracts against against E. coli. The strongest antifungal activity with MIC (4.69mg/ml) and corresponding MFC (4.69mg/ml) was recorded for Cladosporium sp extract against A. versicolor. However, the weakest antifungal activity with the largest MIC (75mg/ml) and corresponding MFC (150mg/ml) was recorded for Candida, & Aspergillus spp extract against A. Niger, and Phoma sp extract against against A. versicolor. The present study demonstrated a sort of direct relationship between the total phenolic content and DPPH radical scavenging activity indicating that the antioxidant activity of the plant extract can be determined the presence of phenolic compounds