Studies On Extraction And Purification Of Xanthohumol Of The Hops And Beer Fermentation

Xanthohumol is the one of main flavonoids in Humunus Lupulus L,and just only in hops could be found. It has been studied by many researchers for its multiple physiology activities. We found a good way to extracte Xanthohumol from the hops with methanol by supersonic and determine it by HPLC. The hops powder was extracted with Supercritical carbon dioxide,from which the cost of the purification produced xanthohumol present by kieselguhr. At the same time, many of hops from different countries and regions were extracted and determined. Finally, the xanthohumol present was standed in the course of beer brewing.The Xanthohumol was extracted with methanol by supersonic. The results indicated that the optimal conditions were as follows: supersonic power was 300W, material and solvent ratio was 1:15, extracting time was3 min, methanol concentration was 100% and extracting temperature was 20℃. The basis of this experiment, The hops powder was extracted with Supercritical carbon dioxide. And then the resultant extraction residue of hop was extracted with Methanol (ethanol) by supersonic. That organic solvent was concentrated , which was mixed homogeneously with kieselguhr.This mixture was eluted by solvent mixture. That solvent mixture was filtrated and freeze-drying , then the yellow solid of product were obtained having a xanthohumol content of 86.2%(w/w) by weight.This yellow solid was recrystallized , and the purity of xanthohumol was 97.8%(w/w). Xanthohumol of 34 samples of hops from different countries and regions were extracted with Methanol by supersonic. The Xanthohumol was determined by HPLC. The results showed that the content of Xanthohumol could be different in different hops, there is much more Xanthohumol in bitter hops than in aroma hops. As the content of alpha acids increases, the levels of Xanthohumol also increase. Storage life of hops could affect the content of Xanthohumol. It will be influence the content of Xanthohumol when the hop pellets were made. Moreover, origin and age of hops have also effect on the content of Xanthohumol.Brewing technology is changing the content of xanthohumol. The Xanthohumol content is totally different from adding it between the beginning of boiling and the end. The fermentation ability of Microzyme in additional xanthohumol present Wort is as the same as the normal Wort. It increased xanthohumol contents by addition xanthohumol present in Wort, but losing a lot.