title: Efficient isolation and purification of five products from microbial biotransformation of cinobufagin by high-speed counter-current chromatography.
abstract: An efficient separation method of using high-speed counter-current chromatography was successfully established to directly purify cytotoxic transformed products of cinobufagin by Cordyceps militaris. The two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (4:6:3:4, v/v) was used in high-speed counter-current chromatography. A total of 9 mg of 4beta,12alpha-dihydroxyl-cinobufagin (1), 15 mg of 12beta-hydroxyl-cinobufagin (2), 8 mg of 5beta-hydroxyl-cinobufagin (3), 12 mg of deacetylcinobufagin (4) and 6 mg of 3-keto-cinobufagin (5) were obtained in a one-step separation from 400 mg of the crude extract with purity of 98.7, 97.2, 90.6, 99.1 and 99.4%, respectively, as determined by HPLC. Their chemical structures were identified on the basis of (1)H-NMR and (13)C-NMR technology. All products (1-5) showed the potent activities against human carcinoma cervicis (Hela) and malignant melanoma (A375) cells in vitro.
authors.affiliation: School of Pharmacy, Dalian Medical University, Dalian, P. R. China.
authors.forename: Xiao-Chi
authors.initials: XC
authors.lastname: Ma
authors.forename: Xiulan
authors.initials: X
authors.lastname: Xin
authors.forename: Bao-jing
authors.initials: BJ
authors.lastname: Zhang
authors.forename: Sha
authors.initials: S
authors.lastname: Deng
authors.forename: Ji-hong
authors.initials: JH
authors.lastname: Yao
authors.forename: Chang-yuan
authors.initials: CY
authors.lastname: Wang
authors.forename: Jian
authors.initials: J
authors.lastname: Cui
authors.forename: Yan
authors.initials: Y
authors.lastname: Tian
authors.forename: Ke-xin
authors.initials: KX
authors.lastname: Liu
mesh_terms: D000970:Antineoplastic Agents / Q000302:isolation & purification* / Q000378:metabolism* / Q000494:pharmacology; D001711:Biotransformation; D002018:Bufanolides / Q000737:chemistry / Q000378:metabolism*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D032661:Cordyceps / Q000378:metabolism*; D003377:Countercurrent Distribution; D004354:Drug Screening Assays, Antitumor; D006367:HeLa Cells; D006801:Humans; D008968:Molecular Conformation; D010936:Plant Extracts / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000970:Antineoplastic Agents; D002018:Bufanolides; D010936:Plant Extracts; C002471:cinobufagin