Electrochemical detection of ursolic acid from spruce (Picea abies) essential oils using modified amperometric microsensors

Biotransformation of Oleanane and Ursane Triterpenic Acids

“…At the same time, an intermediate (6.25%) of the dihydroxylation process-15αhydroxy-3-oxo-olean-12-en-28-oic acid (52)-was also isolated from the culture medium of T. roseum (M 95.56)[114]. C. muscae AS 3.2695 simultaneously catalyzed a wide variety of hydroxylation and glycosylation reactions with the formation of 7β-hydroxy-OA (53), 7β,21β-dihydroxy-OA (54), 7α,21β-dihydroxy-OA (55), 7β,15α-dihydroxy-OA (56), 7β-hydroxy-3-oxo-olean-12-en-28-oic acid(57), 7β,15α-dihydroxy-OA 28-O-β-D-glucopyranosyl ester (58), 21β-hydroxy-OA 28-O-β-Dglucopyranosyl ester(59), and OA 28-O-β-D-glucopyranosyl ester (60) ranging from 3.1% to 5.8%[15]. C7 hydroxylation and C28 glycosylation presumably contributed to an increase in the antiinflammatory activity of derivatives, while C21 hydroxylation led to a decreased ability of compounds to inhibit the release of LPS-induced nitric oxide by RAW 264.7 cells[15].49Colletotrichum lini AS 3.4486 was shown to catalyze the C15 hydroxylation of OA to form 15α-hydroxy-OA(50)[113].…”