Isolation of endophytics fungi from Cola acuminata Schott & Endl, and antifungal activity against Candida Sp

The discovery of novel antifungal agents with low toxicity and high therapeutic efficacy is needed to overcome the limitation of the actually existing antifungal therapies. Endophytic fungi acknowledge for their outstanding ability to produce bioactive metabolites can be exploited for this purpose. Therefore, this study was designed to investigate the antifungal potential of endophytic fungi leaving in tissues of Cola acuminata. Endophytic fungi associated with Cola acuminata were isolated from healthy and matured plant tissues and characterized based on their morphological and microscopic characters. Each isolated fungus was cultured on potato dextrose broth for ten days and crude extract prepared from the resulting medium after filtration. The resulting extracts were tested for their antifungal potential using broth microdilution method. One hundred and six fungal isolates were obtained from leaves, fruit, stem, stem bark, root, and root bark of C. acuminate. They belong to six genera including Aspergillus, Alternaria, Curvularia, Cunnighamella, Fusarium, Trichoderma. Non-sporulating isolates were designated as Mycelia. Out of the 106 extracts screened for their antifungal activities, 21, 13 and 43 showed antifungal activities against C.albicans NR-29450, C.parapsilosis ATCC 22019 and C.krusei ATCC 6258 respectively. Five of these isolates including Cal14, Casb122, Cab259, Cab31 and Cab244 were the most potent, inhibiting the growth of the three tested Candida species more than 85% against. Isolate Casb122 appears to be one of the most potent antifungal against Candida species (MIC 500-1000µg/mL). The results suggest that endophytic fungi from C. acuminata can produce metabolites with antifungal activity