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Microbial transformations of hypolipemic E-guggulsterone.

Atta-ur-Rahman·M I Choudhary·F Shaheen·M Ashraf·S Jahan
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Abstract

Biotransformation of E-guggulsterone (pregna-4,17(20)-cis-diene-3,16-dione) (1) by Aspergillus niger resulted in the formation of four new hydroxyl derivatives identified as 7 beta-hydroxypregna- 4,17(20)-trans-diene-3,16-dione (2), 7 beta-hydroxypregna-4,17(20)-cis-diene-3,16-dione (3), 7 beta- hydroxypregn-4-ene-3,16-dione (4), and 7 beta,15 beta-dihydroxypregn-4-ene-3,16-dione (5). The biotransformation of 1 with Cephalosporium aphidicola also resulted in the formation of four new steroidal derivatives as 11 alpha-hydroxypregna-4,17(20)-trans-diene-3,16-dione (6), 11 alpha- -hydroxypregna-4,17(20)-cis-diene-3,16-dione (7), 11 alpha,15 beta-dihydroxypregna-4,17(20)-trans-diene- 3,16-dione (8), and 11 alpha,15 beta-dihydroxypregna-4,17(20)-cis-diene-3,16-dione (9). The structures of these compounds were elucidated on the basis of 1D and 2D NMR spectroscopic techniques.

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Anti-Bacterial AgentsAnti-Infective AgentsBacteriaBiotransformationFermentationFungiHypolipidemic AgentsMagnetic Resonance SpectroscopyMass SpectrometryMicrobial Sensitivity TestsPregnenedionesSpectrophotometry, InfraredSpectrophotometry, UltravioletJournal ArticleResearch Support, Non-U.S. Gov't

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Atta-ur-Rahman, M I Choudhary, F Shaheen, M Ashraf, S Jahan. 1998. Microbial transformations of hypolipemic E-guggulsterone.. https://doi.org/10.1021/np970473s

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