The microbial transformation of beta-amyrin acetate (compound 1) occurred in the culture of Rhodobacter sphaeroides producing three metabolites. The metabolites were purified and identified as beta-amyrin (compound 2), (3 beta)-olean-12-ene-3, 23-diol (compound 3), and erythrodiol (compound 4). Initially, it was found that beta-amyrin acetate could be deacetylated and hydroxylated by microbial methods.