Bioactive compounds from endophytic fungi Phomopsis sp. from Urobotrya siamensis and isolate LRUB 20 from Leea rubra

Abstract

The purpose of this research was to isolate bioactive compounds from endophytic fungi isolate LRUB 20 from Leea rubra Blume Ex Spreng. and isolate USIA 5 from Urobotrya siamensis Hiepko. Crude extract of endophytic fungus isolate LRUB 20 was purified by chromatographic techniques to afford three compounds, which were identified as asterric acid, 2-hydroxymethyl-3-methyl-cyclopent-2-enone, and 2-hydroxymethyl-3-methyl-cyclopentanone. The crude extract of endophytic fungus isolate USIA 5 provided 3-nitropropionic acid. The chemical structures of the isolated compounds were elucidated through extensive analyses of UV, IR, MS, and NMR and by comparison with literature. Asterric acid, 2-hydroxymethyl-3-methyl-cyclopent-2-enone, and 3-nitropropionic acid were found to exhibit activity against Mycobacterium tuberculosis H37Rv with the MIC values of 200, 200, and 0.39 g/ml, respectively. Based on morphology and nucleotide sequences of ITS1-5.8S-ITS2 regions of rDNA, endophytic fungus isolate USIA 5 was identified as Phomopsis sp. in the family Diaporthaceae. While based on morphology, the fungus isolate LRUB 20 limited in spore formation. Nucleotide sequences of ITS1-5.8S-ITS2 regions of rDNA were applied to classify endophytic fungus isolate LRUB 20, which was found to be in the family Magnaporthaceae