title: Biotransformation of 2alpha,5alpha,10beta,14beta-tetraacetoxy-4(20),11-taxadiene by cell suspension cultures of Catharanthus roseus.
abstract: Catharanthus roseus cell suspension cultures were employed for the biotransformation of 2alpha,5alpha,10beta,14beta-tetraacetoxy-4(20),11-taxadiene ( 1), and four metabolites were obtained. Based on their physical and chemical data, the structures of the four metabolites were respectively elucidated as 10beta-hydroxy-2alpha,5alpha,14beta-triacetoxy-4(20),11-taxadiene (2), 5alpha-hydroxy-2alpha,10beta, 14beta-triacetoxy-4(20),11-taxadiene (3), 6alpha,10beta-dihydroxy-2alpha,5alpha,14beta-triacetoxy-4(20),11-taxadiene (4), and 6alpha,9alpha,10beta-trihydroxy-2alpha,5alpha,14beta-triacetoxy-4(20),11-taxadiene (5), among which 3 and 5 were characterized as new taxoids. The effects of the stages of substrate addition on the biotransformation were also investigated. The results revealed that the biotransformation rate for 1 reached 85.3 % and the yield of 2 70 % when 1 was administered during the mid-linear phase (9 - 12 th day) of the cell growth cycle. On the other hand, the yield for 4 reached the highest level of 11.8 % when 1 was added in the early linear phase (6 th day).
authors.affiliation: The State Key Laboratory of Natural and Biomimetic Drugs, School of Pharmaceutical Sciences, Peking University, Beijing 100083, P.R.China.
authors.forename: Jungui
authors.initials: J
authors.lastname: Dai
authors.forename: Yajun
authors.initials: Y
authors.lastname: Cui
authors.forename: Weihua
authors.initials: W
authors.lastname: Zhu
authors.forename: Hongzhu
authors.initials: H
authors.lastname: Guo
authors.forename: Min
authors.initials: M
authors.lastname: Ye
authors.forename: Qiu
authors.initials: Q
authors.lastname: Hu
authors.forename: Dayong
authors.initials: D
authors.lastname: Zhang
authors.forename: Junhua
authors.initials: J
authors.lastname: Zheng
authors.forename: Dean
authors.initials: D
authors.lastname: Guo
mesh_terms: D019149:Bioreactors; D001711:Biotransformation; D030008:Catharanthus; D002478:Cells, Cultured; D046508:Culture Techniques; D004224:Diterpenes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D015394:Molecular Structure; D013055:Spectrophotometry, Infrared
chemical_list: D004224:Diterpenes