Botrallin from the endophytic fungus Hyalodendriella sp. Ponipodef12 and its antimicrobial activity

Abstract

Bioassay-guided fractionation of the crude methanol extract of the mycelia from the endophytic fungus Hyalodendriella sp. Ponipodef12, associated with the hybrid 'Neva' of Populus deltoides Marsh × P. nigra L., led to the isolation of one compound coded as P12-1 which was identified as botrallin (1,7- dihydroxy-3,9- dimethoxy-4a-methyl-6H- dibenzo [b,d] pyran-2,6 (4aH) -dione) by spectroscopic and physicochemical means. The median inhibitory concentration (IC₅₀) and minimum inhibitory concentration (MIC) of botrallin against Bacillus subtilis were 98.47 μg/ml and 200 μg/ml, respectively. The IC₅₀ values of botrallin against spore germination of Magnaporthe oryzae and Botryosphaeria dothidea were 81.62 μg/ml and 110.02 μg/m, respectively. This is the first report about botrallin and its antimicrobial activity from the endophytic fungus Hyalodendriella sp. Ponipodef12 derived from Populus species.

Key words: Poplar hybrid 'Neva', endophytic fungus, Hyalodendriella sp., botrallin, antimicrobial activity.