Analysis On Content And Structure Of Active Components In Seme Sojae Preparatum And Research On Hypoglycemic Activity Mechanism

This experiment comprised three parts. The objectives of this study were to determine the content of soybean isoflavone and polysaccharides (SSPP) in Seme Sojae Preparatum, analyze structural feature of SSPP initially, and explore the mechanism of hypoglycemic activity and main active components therein. In the first part, comparison was main strategy of study. Firstly, the content difference of isoflavone between Seme Sojae Preparatum and soybean was compared. Secondly, the content difference of aglycone before and afterβ-glucosidase hydrolysis was also compared. It was proved thatβ-glucosidase could effectively improve the content of aglycone, and the important role of bioconversion during the course of soybean fermentation was also elucidated. Besides, we tried to illuminate the reason that black soybean was always used as the raw material for Seme Sojae Preparatum fermentation. Ultrasonic wave was exployed to extract isoflavone and polysaccharides from Seme Sojae Preparatum, black soybean and soybean, while quantified by HPLC and UV respectively. Moreover, soybean isoflavone glucosides were transformed to aglycones byβ-glucosidase. The experiment indicated that the content of isoflavone was the most in Seme sojae preparatum, and black soybean was the least, even Seme sojae preparatum had further more content than the other two soybeans. Additionally, the content of isoflavone aglycones after hydrolysis had a great rise.In the second part of experiment, the main purpose was to analyze the mechanism of hypoglycemic activity of Seme sojae preparatum, and to determine the main active components of hypoglycemic activity in Seme sojae preparatum. PNPG was used as substrate in vitro inhibition reaction of a-glucosidase, while Seme sojae preparatum, soybean isoflavone and SSPP were recruited as inhibitors respectively. Inhibition ratios were calculated according to PNP concentrations. Two kinds of optimal reaction systems were screened out through a series of mono-factor experiments. Under respective optimal reaction condition, the inhibition ratio of aqueous extract of Seme sojae preparatum could reach 54.8%, and inhibition ratio of soybean isoflavone was approximately 30.2%. However, SSPP didn't exert any influence on a-glucosidase. Therefore, it's proved that mechanism of hypoglycemic activity of Seme sojae preparatum was associated with a-glucosidase inhibition, and soybean isoflavone played an important role in this process. Additionally, SSPP had no hypoglycemic activity or had different mechanism of hypoglycemic activity.In the third part of the experiment, the physico-chemical property and compositions of SSPP were analyzed, besides, the structural features of SSPP were also discussed initially by IR spectrumn. SSPP was extracted and purified from Seme Sojae Preparatum by the method of Sephadex G-100 column chromatography. Additionally, the weights were determined by using gel-permeation chromatograph (GPC), and the structure characterizations were analyzed by IR spectrum. It was suggested that SSPP was made up of SPSS I and SPSS II. Both of them were uniform polysaccharide, which Mw were about 9500 and 7000 respectively. IR spectrumn showed that they all had the typical structure characterizations of polysaccharide.