The Study Of The Water Soluble Saponins From The Dioscorea Zingiberensis C.H.Wright

Dioscorea zingiberensis C. H. Wright is one of the eight hundred fifty species of the family Dioscorea, commenly grown in the north subtropical and middle subtropical region. Many members of this family were used as folk medicines for various diseases. Dioscorea zingiberensis C. H. Wright mainly contained steroid saponins and many other bioactive natural products. The steroid saponins were mainly divided into two parts including water-soluble fraction and lipid-soluble fraction. There was little study in the water-soluble fraction at this time, and the chemical component is still unknown. The paper illuminates the study about the saponins in water fraction from Dioscorea zingiberensis C. H. Wright in three fields:1. The structures of the saponins in water fraction from Dioscorea zingiberensis C. H. Wright were isolated. Fresh roots of the Dioscorea zingiberensis C. H. Wright were cutted up and then were distilled with boiling water. The refreshants were extracted and the water fraction was kept. The water fraction were isolated by the reversed-phase ODS column and MCI column chromatographic. 5 saponins were isolated from the water fraction.2. The chemical structures were elucidated by means of 1H-NMR,13C-NMR,135DEPT,HMQC and HMBC spectroscopic analyses. One of the compounds is a novel compound named as zingiberenin H. The compounds were identified as: diosgenin- 3-O-β-D-glucopyranosyl(1→3)-β-D-glucopyranosyl(1→4)-[α-L-rhamnopyranosyl(1→2)]-β-D- glucopyranoside(Ⅰ);(25R)-26-O-β-D-glucopyranosyl-furost-5-en-3β,22ξ-diol -3-O-β-D -glucopyranosyl(1→3)-β-D-glucopyranosyl(1→4)-[α-L-rhamnopyranosyl(1→2)]-β-D-glucopyranoside (Ⅱ) and (25R)-26-O-β-D-glucopyranosyl-5-furost-en- 3β,22ξ-diol- 7- carbonyl -3-O-β-D-glucopyranosyl(1→3)-β-D-gl-ucopyranosyl (1→4)-[α-L-rhamnopyranosyl (1→2)] -β-D-glucopyranoside (Ⅲ), (25R)-26-O-β-D-glucopyranosyl-furost-5-en-3β, 22ξ, 26- triol-3-O-β-D-glucopyranosyl(1→4)-[α-L-rhamnopyranosyl(1→2)]-β-D- glucopyrano–side(Ⅳ), Sterol(Ⅴ)3. Chromatographic analysis of the isolated saponins were made. The contents of the two saponins from Dioscorea zingiberensis C. H. Wright were analyzed by reversed-phase high performance liquid chromatography using XBridgeTM C18 column(250mmx4.6mm,5μm) with Acetonitrile-water solution as mobile phase. The contents of the compounds are 7.77% and 4.61% in the water soluble part respectively, The contents of the compounds are 0.114% and 0.068% in Dioscorea zingiberensis C. H. Wright respectively...