Two new oleanane-type triterpenes isolated from Japanese post-fermented tea produced by anaerobic microbial fermentation.

Four triterpenes were isolated from a traditional Japanese tea product produced by anaerobic microbial fermentation of heated green tea leaves (Camellia sinensis). Two of the compounds were novel and characterized by spectroscopic investigation to be 13,26-epoxy-3ß,11α-dihydroxyolean-12-one and 3ß,11α,13ß-trihydroxyolean-12-one. Two known triterpenes were identified as taraxastane-3ß,20ß-diol and taraxastane-3ß,20α-diol. These triterpenes were not detected in the original green tea leaves.