A previous study on the leaves of Tabernaemontana pandacaqui Poir showed that a bioactive constituent against the bacteria Bacillus subtilis was detected in the butanol extract using a modified bioautographic method. This study deals with the isolation and structure elucidation of the major compound from the bioactive fraction of the leaf extract.
The crude alcoholic extract from the dried leaves was subjected to a series of solvent extraction. The butanol extract was found to be active against B. subtilis. Through a series of fractionation by column chromatogrpahy, a major compound was isolated from the hexane: chloroform (8:2) ratio. This was identified as a-amyrin acetate using the combined spectral techniques of IR, MS, 1H-NMR, J mode 13C-NMR, COSY, H-C COBIDEC, HMBC and NOESY.