VOLUME 11 (Supplement)

by Llewelyn S. Moron^1,2, Young-Woon Lim³, and Thomas Edison E. dela Cruz^1,2*

¹The Graduate School, and ²Fungal Biodiversity, Ecogenomics and Systematics Group,
     Research Center for the Natural and Applied Sciences, University of Santo Tomas,
     España, Manila 1008 Philippines
³School of Biological Sciences, Seoul National University,
     Gwanak-Gu Seoul 08826, South Korea

Mangrove fungal endophytes (MFE) are potential sources of bioactive metabolites that can be tapped by local pharmaceutical companies in the development of new drugs. In this study, 40 selected MFE, previously isolated from healthy stems and roots of 12 host mangrove species, were identified based on morphology and/or ITS sequence analysis and cultured for the production of bioactive secondary metabolites. The common MFE identified were Arthrinium phaeospermum, Colletotrichum siamense, C. tropicale, Fusarium oxysporum, F. chlamydosporum, F. proliferatum, F. solani, Lasiodiplodia theobromae, Nodulisporium sp., Paecilomyces formosus, Penicillium citrinum, and Pestalotiopsis microspora. The secondary metabolites were extracted from mycelial mass of MFE grown in vitro using liquid cultures and screened for antimicrobial activities against eight bacterial and two yeast species using the paper disk diffusion and microdilution assays. Twenty-two MFE exhibited inhibitory activities against at least one of these test microorganisms. Results also showed that Pestalotiopsis microspora (MFE 24) showed strong antimicrobial activities against gram-positive bacteria while species of Lasiodiplodia were very active against Saccharomyces cerevisiae with minimum fungicidal concentration of <7.8 μg/mL, indicating their potential as sources of bactericidal and/or fungicidal compounds.