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Microbial transformations of isosteviol.

Feng-Lin Hsu·Chia-Chung Hou·Li-Ming Yang·Juei-Tang Cheng·Tzong-Cherng Chi·Pang-Chun Liu·Shwu-Jiuan Lin
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Abstract

Microbial transformations of the tetracyclic diterpenoid isosteviol (ent-16-ketobeyeran-19-oic acid) (2) have revealed that isosteviol is metabolized by Cunninghamella bainieri, Actinoplanes sp., Mucor recurvatus, and Cunninghamella blakesleeana to yield five new metabolites, ent-11alpha,12alpha-dihydroxy-16-ketobeyeran-19-oic acid (5), ent-11alpha,12alpha,17-trihydroxy-16-ketobeyeran-19-oic acid (6), ent-12alpha,15alpha-dihydroxy-16-ketobeyeran-19-oic acid (7), ent-7alpha,15alpha-dihydroxy-16- ketobeyeran-19-oic acid (8), and ent-9alpha-hydroxy-16-ketobeyeran-19-oic acid (9), together with three known metabolites, ent-7alpha-hydroxy-16-ketobeyeran-19-oic acid (3), ent-7beta-hydroxy-16-ketobeyeran-19-oic acid (4), and ent-12alpha-hydroxy-16-ketobeyeran-19-oic acid (10). The structures of these metabolites were established on the basis of HRFABMS and 1D and 2D NMR spectral data. In addition, metabolites 3-10 were tested for antihypertensive activity and were found to be less active than the parent compound 2.

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Antihypertensive AgentsBiotransformationDiterpenesDiterpenes, KauraneFungiHydrolysisMolecular StructureNuclear Magnetic Resonance, BiomolecularStereoisomerismComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Feng-Lin Hsu, Chia-Chung Hou, Li-Ming Yang, Juei-Tang Cheng, Tzong-Cherng Chi, Pang-Chun Liu, Shwu-Jiuan Lin. 2002. Microbial transformations of isosteviol.. https://doi.org/10.1021/np000622y

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