title: [Optimization of extraction process for tannins from Geranium orientali-tibeticum by supercritical CO2 method].
abstract: In order to optimize extraction process conditions of tannins from Geranium orientali-tibeticum by supercritical CO2, the content of tannins was determined by phosphomolybdium tungsten acid-casein reaction, with extraction pressure, extraction temper- ature and extraction time as factors, the content of tannins from extract of G. orientali-tibeticum as index, technology conditions were optimized by orthogonal test. Optimum technology conditions were as follows: extraction pressure was 25 MPa, extraction temperature was 50 °C, extracted 1.5 h. The content of tannins in extract was 12.91 mg x g(-1), extract rate was 3.67%. The method established could be used for assay the contents of tannin in G. orientali-tibeticum. The circulated extraction was an effective extraction process that was stable and feasible, and that provides a way of the extraction process conditions of tannin from G. orientali-tibeticum.
authors.forename: Song
authors.initials: S
authors.lastname: Xie
authors.forename: Zhi-Ping
authors.initials: ZP
authors.lastname: Tong
authors.forename: Rui
authors.initials: R
authors.lastname: Tan
authors.forename: Xiao-Zhen
authors.initials: XZ
authors.lastname: Liu
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D005591:Chemical Fractionation / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D031315:Geranium / Q000737:chemistry*; D013634:Tannins / Q000302:isolation & purification*
chemical_list: D004365:Drugs, Chinese Herbal; D013634:Tannins; D002245:Carbon Dioxide