Research On Chemical Components And α-glucosidase Inhibiting Activity Of Huzhang

The Huzhang,a crude material of traditional Chinese medicine, is from the dried roots and rhizomes of Polygonum cuspidatum Sieb. et Zucc, which could be used for functions of dehumidification, clearing heat and relieving toxin, decreasing blood lipid, etc. Anthraquinone, styrene and flavonoids are its dominant components. The component content of anthraquinone and styrene is much more than others and they also have widely pharmaceutical activity. It can be used to treat diabetes, liver disease, especially resveratrol has multi-functions including the antioxidant activity, anticancer and antibacterial, etc. The research value thus is very high. Therefore, the Huzhang was selected as the research objective, its optimal extraction of α-glucosidase inhibitors from this plant was studied, and separating its monomer compounds companying with setting up a quantitative analysis of multi-components by single marker(QAMS) to evaluate medicinal materials quality of the crude drug produced in different origins. A method to determinate anthraquinone content was developed, and the activity of it in decreasing blood glucose was researched also. All of above will provide more experiment basis for clinical application of drug.Firstly, it is optimized that the extraction process of inhibit α-glucosidase active ingredient from Huzhang through multi-index comprehensive evaluation with orthogonal design. The ethanol concentration, extraction times and time, solvent dosages were designed as investigative factors, contents of polydatin, emodin, physcion and α-glucosidase inhibition activity as indexes were optimized by orthogonal design, ultimately determine the optimal extraction process, lay the material foundation for the study of inhibition of α-glucosidase. The optimal process is that the herbs are refluxed 2 times with total 8 times of 70% Et OH, 2h for each time. These three kinds of chemical components, polydatin, emodin and physcion have an positive effect on Huzhang inhibiting α-glucosidase.Secondly, Huzhang was extracted according to the best extraction process. It is extracted with different polarity solvent and the activities were tracked. Then, it is extracted with 70% Et OH to get the total extract of Huzhang, and next step is to extract it with cyclohexane-ethyl acetate(2:1) and ethyl acetate, there are three insoluble parts of cyclohexane-ethyl acetate(2:1), ethyl acetate and the ethyl acetate were obtained. Analysis of the 4 parts, the total extract, cyclohexane-ethyl acetate(2:1), ethyl acetate and the ethyl acetate insoluble through HPLC and α-glucosidase inhibitors, every part have inhibitive effect and the best part is the total extract.Thirdly, silica gel chromatography column and C18 packing column chromatography were used for further separation of total extract in Huzhang. Analysis of the results of C-NMR and H-NMR, compared with the literature at the same time, they were identified to be emodin, physcion, rhein, chrysophanol, emodin-8-O-β-D-glucoside, physcion-8-O-β-D-glucoside, polydatin, and resveratrol respectively.Fourthly, a quantitative method is established for simultaneously determining the six components in Huzhang, which are emodin, physcion, emodin-8-O-β-D-glucoside, physcion-8-O-β-D-glucoside, polydatin and resveratrol by using one chemical standard substance and validate its feasibilities. This has provided a simple, fast and reliable method for determinating the content of a variety of chemical components in Huzhang. With Huzhang as the research object, using emodin as internal standard, the relative correction factors(RCF) and retention time of other five components at 290 nm were established. Chromatographic peak position with relative retention time and the contents of the five other ingredients were calculated by their RCF. The contents of the six components from different producing areas calculated by RCF method were compared with the measured values of external standard method. The results show that no significant differences were observed between the quantitative results of quantitative analysis of multi-components by single marker and external standard method(ESM). It is reliable to determinate the content and evaluate the quality of Huzhang by QAMS. At the same time, TLC for qualitative identification experiment of Huzhang was used, and a more convenient and fast quality evaluation system of Huzhan was built, achieving the purpose of simple, rapid and multi-index measurement.Fifthly, UV spectrophotometric method of determining total anthraquinone content of Huzhang has been developed. The total anthraquinone content in Huzhang was determined with three-wavelength UV spectrophotometric method and the drugs from different origins were scanned. The results showed, it can’t be used to determinate all the anthraquinone content in Huzhang from different origins with a system of three-wavelength, it has limitations. Huzhang was hydrolyzed, and it was determined more accurately with pectrophotometric method combined with the method of magnesium acetate, the results show that UV and HPLC are similar, the accurate value can be get. These provide a convenient, quick and reliable method for determining total anthraquinone content of Huzhang from different origin.Finally, the rat model of resistant diabetic insulin was set up. It could provide more experimental data for the clinical application and pharmacological action researched of Huzhang through testing every indicator, developing the effect on blood sugar and blood fat from the total extract, and determining the pharmacological activities.