Microbial hydroxylation and glycosidation of oleanolic acid by and their anti-inflammatory activities.

Biotransformation of oleanolic acid (OA) by AS 3.2695 was investigated. Nine hydroxylated and glycosylated metabolites () were obtained. Their structures were elucidated as 3β,7β-dihydroxyolean-12-en-28-oic acid (), 3β,7β,21β-trihydroxyolean-12-en-28-oic acid (), 3β,7α,21β-trihydroxyolean-12-en- 28-oic acid (), 3β,7β,15α-trihydroxyolean-12-en-28-oic acid (), 7β,15α-dihydroxy- 3-oxo-olean-12-en-28-oic acid (), 7β-hydroxy-3-oxo-olean-12-en-28-oic acid (), oleanolic acid-28-O-β-D-glucopyranosyl ester (), 3β,21β-dihydroxyolean-12-en-28- oic acid-28-O-β-D-glucopyranosyl ester (), and 3β,7β,15α-trihydroxyolean-12-en- 28-oic acid-28-O-β-D-glucopyranosyl ester () by spectroscopic analysis. Among them, compounds and were new compounds. In addition, anti-inflammatory activities were assayed and evaluated for the isolated metabolites. Most of the metabolites exhibited significant inhibitory activities on lipopolysaccharides-induced NO production in RAW 264.7 cells.