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Mulberry leaf is a traditional Chinese medicine, contains flavonoids, polysaccharides, alkaloids and other compounds. Has a variety of biological activity and clinical applications, primarily for the treatment of diabetes, hypertension and other illnesses. 1 - deoxynojirimycin (1-deoxynojirimycin, referred DNJ), represented by polyhydroxy alkaloids as mulberry leaves hypoglycemic ingredient has been highly concerned about the domestic and foreign scholars. Mulberry hypoglycemic studies, mostly concentrated in the mulberry leaf crude extract activity test research, few of the monomer components active research reports, especially DNJ analogues rare . Water extract of mulberry object of study, used mainly economical and the separation of the conventional ion exchange method to obtain 7 kinds of the monomer component, the use of hypoglycemic activity test in vitro model to its hypoglycemic activity, respectively, were studied, and the possible reduction The blood sugar mechanism of a preliminary study. 1, using hydrophilic interaction column, and the establishment of a 1 - deoxynojirimycin and its analogues HPLC-ELSD analysis method. The method than derivatization method is simple, fast, fast qualitative and quantitative analysis of the mulberry leaf samples. 2, using distilled water as a solvent, using an ultrasonic assisted extraction on mulberry samples were extracted, purified by repeated ion exchange resin separation and final Sephadex gel chromatography, to give a total of seven kinds of monomer components. Structure identification by HPLC-MS and NMR, respectively, DNJ, and three of its analogs 2-O-α-D-galactopyranosyl-1-deoxynojirimycin, fagomine, 1,4-dideoxy-1 ,4-imino-(2 - O-β-D-glucopyranosyl)-D-arabinitol, and myo-inositol and two undetermined structure of the monomer material. 3 hypoglycemic activity in vitro screening model and use the model to study the hypoglycemic activity of the separation of substances. Seven kinds of monomer substance isolated, 6 of which have significant hypoglycemic activity. Wherein minimum of DNJ in the IC50 of the α-glucosidase, respectively sucrose substrate and maltose substrate reached 0.30μg/mL and 1.68μg/mL. Myo-inositol and 2-O-alpha-D-galactopyranosyl-1-deoxynojirimycin also shows a strong hypoglycemic activity, the IC50 with positive control glucoby considerable. DNJ hypoglycemic activity suppression type inspection by the Lineweaver-Burk method, the results showed that the α-glucosidase DNJ substrate of sucrose and maltose substrates suppression type are mixed competitive inhibition. 4, the paper also studied the laws of 26 different varieties of Mulberry Leaf Extracts of hypoglycemic activity varies with the different seasons. The results show that most of mulberry leaves (Mulberry season) varieties from May to October (frost season) with seasonal month increments, lowering the hyperglycemic activity have weakened the trend, the highest month in May. 26 mulberry leaf varieties, farmers 14,306,402, Jialing No. 16, No. 20, Jialing five samples demonstrated strong hypoglycemic activity. Mulberry hypoglycemic effect of further research and utilization of Mulberry hypoglycemic composition and activity of research this subject has better theoretical guidance value.
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