Microbial transformations of isosteviol.
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.
Hsu
Feng-Lin
FL
Graduate Institute of Pharmaceutical Sciences, Taipei Medical University, Taipei, Taiwan 110, Republic of China.
Hou
Chia-Chung
CC
Yang
Li-Ming
LM
Cheng
Juei-Tang
JT
Chi
Tzong-Cherng
TC
Liu
Pang-Chun
PC
Lin
Shwu-Jiuan
SJ
D000959:Antihypertensive Agents / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D001711:Biotransformation; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D045786:Diterpenes, Kaurane; D005658:Fungi / Q000378:metabolism*; D006868:Hydrolysis; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism
D000959:Antihypertensive Agents; D004224:Diterpenes; D045786:Diterpenes, Kaurane; C012042:steviol