| Processing drugs becomes a feature of Traditional Chinese Medicine(T.C.M). The relative contents of flavonoid glycosides in Herba Epimedii would transform under heating temperature of processing. But it is not clear that how heating temperature and heating time affect these transformation. Meanwhile, there lies a series of biotransformation with enzyme and microorganism involved in the body, which caused biotransformation of processed flavonoid glycosides. However, the rules between them were less researched. So the synergia effect of flavonoid glycosides in Herba Epimedii through ways of physico- and bio-transformationshould be studied. Experiments had been done from the following aspects:①The ethanol extraction was applied in the extraction of flavonoid glycosidesfrom herba Epimedii, and Epimedin A, B, C(purities were above 98%) were isolated and purified by macroporous resin column, normal/reversed phase silica gel column and preparative liquid chromatography, which was essential for the experiment to go on smoothly.②The effect of heating temperature and heating time, two processing key factors, on transformation of flavonoid glycosides were considered. In this study, Epimedin A, B, C and Icariin were taken as marker compound to compare the transformation of extract of Epimedium and its eluate of water, 30%, 50% ethanol through macroporous adsorptive resins and then compared to the four flavonoid glycoside monomers. All that were refluxed with boiling for 12h. These results showed that the increase of Icariin was transformed from polycose glycoside, but not from Epimedin A, B, C .The polarity of polycose glycoside was stronger than Epimedin A, B, C. Moreover, the experiments of contents variation of Epimedin A, B, C and Icariin monomer were also performed in different temperature for 2 hours. The results showed that 160°C was a transition temperature for Epimedin A, B and Icariin, and Epimedin C had lower stablility. The degeneration products of Epimedin A, B,C were not Icariin.③The biotransformation of flavonoid glycosides by intestinal bacteria was studied, and the metabolites of Epimedin A, B, C were identified for the first time by using LC-MS/MS technique. Icariin was metabolized in 12 hours quickly and completely. However, Baohuoside I , the metabolite of Icariin, had a lower transformation efficiency, which indicated that it was possible that Baohuoside I was decomposed by intestinal bacteria. When four flavonoid glycosides of the equal mass were incubated for 4 hours by intestinal bacteria, Epimedin A, B, C could not be detected except for Icariin.The results showed that metabolism of Epimedin A, B, C by intestinal bacteria was stronger than that of Icariin.④The studies on intestinal metabolism experiment of Epimedin A, B, C were performed by using in situ perfused rat intestinal model. The results showed that a glucosyl group at C-7 of Epimedin A, B, C was cleaved by intestinal enzyme to produce sagittatoside A, sagittatoside B and 2"-O-rhamnosylicariside II, respectively. The research done by other members in our team showed that epimedin flavonoids, with sugar attached to two different phenolic groups on the flavonoid ring, were poorly permeable. Removal of a glucose molecule (from 7-O position) maked the compound more permeable.In general, Epimedium flavonoid glycosides were metabolized into their secondary glycosides by intestinal enzyme and bacteria. The secondary glycosides were better permeable and easier to be absorbed.These conclusions supported previous hypothesis: to optimize heatig temperature and time would alter relative ratio of flavonoids in herba epimedii, then the flavonoid glycosides transformed into their secondary glycosides by intestinal enzyme and bacteria. The permeability coefficient of deutero-polycose glycoside was higher than that of polycose glycoside, so the absorption of polycose glycoside is much better. So we drew a conclusion that physico- and bio-transformation can elevated the absorption of flavonoids in herba epimedii in vivo.
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