Microbial transformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans.

Microbial biotransformation of acetyl-11-keto-boswellic acid by Cunninghamella elegans AS 3.1207 was carried out, and totally four transformed products were isolated. On the basis of the extensive spectral data, their structures were characterized as 7ß-hydroxy-11-keto-boswellic acid (1), 7ß,30-dihydroxy-11-keto-boswellic acid (2), 7ß,16α-dihydroxy-3-acetyl-11-keto-boswellic acid (3), and 7ß,15α,21ß-trihydroxy-3-acetyl-11-keto-boswellic acid (4), respectively. Among them, products 1 and 2 are the new compounds.