- Microbial hydroxylation and methylation of genistein by Streptomycetes
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Streptomyces griseus (ATCC 10137) and Streptomyces catenulae (ATCC 23893) were used to convert genistein-5,7,4'- trihydroxyisoflavone (1)-a major isoflavone found in soybeans, into five metabolites, four of which were previously unknown. These were 5,7,3',4'-tetrahydroxy-8-methylisoflavone (3), 5,7,3',4'-tetrahydroxy-8-methylisoflavanone (4), 5,7,4'- trihydroxy-3'-methoxyisoflavone (5), 5,7,8,3',4'-pentahy- droxyisoflavone (7), and the known compound, 5,7-dihydroxy-3',4'- dimethoxyisoflavone (6). Identities of these metabolites were established by HRFABMS and 1D and 2D NMR correlation spectroscopy.
- Hosny, Mohammed,Rosazza, John P. N.
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Read Online
- Production and anti-melanoma activity of methoxyisoflavones from the biotransformation of genistein by two recombinant Escherichia coli strains
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Biotransformation of the soy isoflavone genistein by sequential 3′-hydroxylation using recombinant Escherichia coli expressing tyrosinase from Bacillus megaterium and then methylation using another recombinant E. coli expressing O-methyltransferase from S
- Chiang, Chien-Min,Chang, Yu-Jhe,Wu, Jiumn-Yih,Chang, Te-Sheng
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- A Versatile Microbial System for Biosynthesis of Novel Polyphenols with Altered Estrogen Receptor Binding Activity
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Isoflavonoids possess enormous potential for human health with potential impact on heart disease and cancer, and some display striking affinities for steroid receptors. Synthesized primarily by legumes, isoflavonoids are present in low and variable abundance within complex mixtures, complicating efforts to assess their clinical potential. To satisfy the need for controlled, efficient, and flexible biosynthesis of isoflavonoids, a three-enzyme system has been constructed in yeast that can convert natural and synthetic flavanones into their corresponding isoflavones in practical quantities. Based on the determination of the substrate requirements of isoflavone synthase, a series of natural and nonnatural isoflavones were prepared and their binding affinities for the human estrogen receptors (ERα and ERβ) were determined. Structure activity relationships are suggested based on changes to binding affinities related to small variations on the isoflavone structure.
- Chemler, Joseph A.,Lim, Chin Giaw,Daiss, John L.,Koffas, Mattheos A.G.
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experimental part
p. 392 - 401
(2011/06/28)
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