Separation And Purification Of Gypenoside From Gynostemma Pentaphyllum And Study On Enzymatic Conversion

In order to obtain gypenoside monomer from Gynostemma pentaphyllum (Thunb.) Makino, this paper mainly studied on extraction,separation, purification and bio-enzymatic conversion of gypenoside.The gypenoside was extracted by alcohol and separated by resin, purified by silica gel column chromatography.Grinded gynostemma pentaphyllum was extracted with75%alcohol repeatedly for3times. After the extracting solution was defatted by petrolero, extracted by water saturated butanol, desugared by AB-8macroporous resin, decoloured by D-296ion exchange resin, we got the gypenoside whose yield is0.1574%, the content of gypenoside was84.58%.Adopting static absorption to determine the absorption capacity of AB-8macroporous resin, the absorption capacity can achieve33.57mg/mL.To determine the loss of saponin dealed with D-296ion exchange resin, we carried out three parallel tests, the average loss was0.595mg/mL.The gypenoside was separated by silica gel column chromatography.Three kinds of gypenoside were obtained from gypenoside. Gypenoside monomer A appeared after2700mL chloroform and methanol the proportion in9.5:0.5eluted.Gypenoside monomer B appeared after1100mL chloroform and methanol the proportion in9:1eluted.Gypenoside monomer C appeared after2700mL chloroform and methanol the proportion in9:1eluted.The yield of these elements was2.6%,3.0%,5.2%. Every element was detected by HPLC. The relative peak area ratio was up to88.73%,93.11%,78.54%respectively.Based on this, selected Absidia sp. g48bacteria to produce enzyme, the enzyme reaction of gypenoside and three kinds of gypenoside monomer was studied. The enzyme reaction characteristics showed that this kind of glycosidase can act on gypenoside monomer C obviously,parts of glycosyl group was inversed by this glycosidase, gypenoside monomer A can’t be inversed by this glycosidase,gypenoside monomer B was inversed a little.