title: Enantioselective production of 3-hydroxy metabolites of tibolone by yeast reduction.
abstract: The enantioselective reduction of tibolone into the corresponding 3alpha-hydroxy or 3beta-hydroxy metabolite can be controlled by choosing suited strains of yeasts and biotransformation conditions. A restricted screening performed among 52 yeasts showed that the 3alpha-epimer was preferentially obtained with high epimeric purity with various strains (i.e. with Kluyveromyces lactis CBS 2359), while only Saccharomyces cerevisiae CBS 3093 gave the 3beta-epimer as major product. The reduction of tibolone with K. lactis CBS 2359 and S. cerevisiae CBS 3093 was optimised. S. cerevisiae CBS 3093 furnished a 96:4 ratio of 3beta/3alpha with complete molar conversion within 72h when the initial concentration of substrate was below 2.5g/L. K. lactis CBS 2359 gave a 99:1 ratio of 3alpha/3beta with complete conversion in 64h.
authors.affiliation: Dipartimento di Scienze e Tecnologie Alimentari e Microbiologiche, Università degli Studi di Milano, via Celoria 2, 20133 Milano, Italy.
authors.forename: Diego
authors.initials: D
authors.lastname: Romano
authors.forename: Valerio
authors.initials: V
authors.lastname: Ferrario
authors.forename: Diego
authors.initials: D
authors.lastname: Mora
authors.forename: Roberto
authors.initials: R
authors.lastname: Lenna
authors.forename: Francesco
authors.initials: F
authors.lastname: Molinari
mesh_terms: D001711:Biotransformation; D007716:Kluyveromyces / Q000378:metabolism; D015394:Molecular Structure; D009652:Norpregnenes / Q000737:chemistry* / Q000378:metabolism*; D010084:Oxidation-Reduction; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D013237:Stereoisomerism; D015003:Yeasts / Q000378:metabolism*
chemical_list: D009652:Norpregnenes; C027385:tibolone