An endophytic fungus was isolated from surface sterilized leaf segments of an orchid endemic to Sri Lanka, and was identified as sp. by morphological characters and DNA sequencing. Bioassay-guided chromatographic fractionation of the organic extract of a laboratory culture of this fungus led to the isolation of the known antibacterial helvolic acid. Helvolic acid was active against the Gram-positive bacteria, [minimal inhibitory concentrations (MIC), 2 μg mL] and methicillin-resistant (MIC, 4 μg mL).
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| http://dx.doi.org/10.1080/21501203.2014.892905 | DOI Listing |
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