| α-Glucosidase plays an important role in carbohydrate metabolism and glycoprotein processing.It is mainly expressed on the brush edge of small intestinal mucosal cells.It can selectively hydrolyze starch or disaccharide to release a single glucose molecule.According to statistics,the prevalence of diabetes among Tibetans in China is significantly lower than that of other ethnic groups.By studying the dietary structure of Tibetans,it is found that the main daily carbon water diet is highland barley.Therefore,this paper takes highland barley as the research object to inhibit it α-The ability of glucosidase was studied in order to screen effective glucosidase α-Glucosidase inhibitor can improve diabetes.In this study,different solvents were used to extract active substances from highland barley α-The screening of glucosidase inhibition system showed that n-hexane extract had excellent activity α-After optimization of extraction process,fatty acid composition analysis,enzyme kinetics analysis,in vitro simulated digestion and establishment of Caco-2 cell model,the expression of transport genes in glucose transport related gene Na +-glucose co transport vector system(SGLTs)and glucose assisted diffusion transport vector system(GLUTs)were further studied.The results showed that:1.The fat-soluble extract has a good inhibitory effect on α-glucosidase.The fat-soluble components in highland barley bran were extracted with n-hexane,ethyl acetate and ethanol,respectively.It was found that the n-hexane extract inhibitedα-glucosidase.The ability of glucosidase is the strongest(IC50 value is 0.736 mg/m L);followed by ethyl acetate solvent extract(IC50 value is 0.953 mg/m L);while ethanol solvent extract has lower inhibitory ability(IC50 value is 1.304 mg/m L)m L).The IC50 value of acarbose is 0.867 mg/m L,and it can be seen that the inhibitory effect of n-hexane is stronger than that of acarbose,while the inhibitory effect of extracts from other solvents is obviously not as good as that of n-hexane.After optimizing the extraction process of highland barley bran oil,the maximum extraction rate can reach3.62%.The optimal extraction factor ratios were as follows: ultrasonic time,power,temperature and extraction time were 30 min,225w,30℃,and 12 h,respectively.2.Highland barley bran oil(HBBO)is mainly composed of unsaturated fatty acids.The content of unsaturated fatty acids accounted for 79.74% of the total content,and the highest content of unsaturated fatty acids was linoleic acid,which accounted for 53.05% of all fatty acids.In addition,the type of inhibition of α-glucosidase by HBBO was found to be mixed-type reversible inhibition by enzyme kinetics analysis.After oral,gastric and intestinal digestion,its glycosidase inhibitory ability showed a trend of first decreasing and then increasing..3.HBBO can significantly inhibit Caco-2 intracellular α-glucosidase.At lower concentrations,it can promote the activity of Caco-2 cells and inhibit the intracellular glucose production of Caco-2 cells.The effects of different concentrations of HBBO on Caco-2 cells were studied and found that HBBO had a significant inhibitory effect on α-glucosidase in a concentration-dependent manner,and down-regulated the expression of α-glucosidase m RNA.The gene expression of glucose transport related genes Na+-K+-ATPase,SGLT-1 pathway and GLUT-2 pathway were all down-regulated.Conclusion: Highland barley bran oil can effectively inhibit the activity ofα-glucosidase,and its main component is unsaturated fatty acid.The inhibitory effect on α-glucosidase is mixed reversible inhibition,and it can still effectively inhibitα-glucosidase after being digested by the digestive system.-Glucosidase can inhibit the production of α-glucosidase and intracellular glucose in Caco-2 cells,and down-regulate the expression of α-glucosidase,Na+-K+-ATPase,SGLT-1 and GLUT-2 genes. |
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