Study On Extraction And Identification Of Active Components From Miao Medicine Polygonum Capitatum

Polygonum capitatum is a plant belonging to the genus Polygonaceae and it is a folk herb commonly used in the fields of Qingrejiedu,diuretic Tonglin,pyelonephritis,and cystitis.It is rich in flavonoids,phenolic acids,organic acids,alcohols,lipids,aldehydes and other active ingredients.The extraction process of antibacterial active ingredients of Polygonum capitatum was studied,and the main chemical constituents were analyzed.At the same time,activity of Polygonum capitatum on?-glucosidase inhibitory was also researched,which provided a theoretical reference value for the development and application of Polygonum capitatum.The conclusions of this study are as follows:1.The extraction rate and antibacterial activity as indicators,the effects of ethanol volume fraction,extraction temperature,solid-liquid ratio,and extraction time on the extraction rate and antibacterial activity were studied by single factor experiments.Using Box-Benhnken's central combinatorial experimental design principle,the response surface was used to optimize the extraction process and the best extraction conditions were determined:79%ethanol as the solvent,and the ratio of solid to liquid was 1:25 g.mL-1,reflux extraction at 80°C for 1.5 h;Extract of polygonum capitatum has good antibacterial activity against Staphylococcus aureus and E.coli.The inhibitory zone of extract against Staphylococcus aureus was 13 mm at 20mg·mL^-1,the inhibitory zone against E.coli was 11.5 mm at 50 mg·mL^-1.2.In order to track the antibacterial active parts of Polygonum capitatum,the crude extract of Polygonum capitatum were divided into petroleum ether phase,chloroform phase,and ethyl acetate phase,Butanol phase,aqueous phase five different polar extracts by using liquid-liquid extraction,Then,the contents of total flavonoids and total polyphenols in different polar solvent extracts were measured,and the different polar extracts were tested for antibacterial activity.The ethyl acetate phase with the best antibacterial activity was selected and divided into 20%,40%,60%,80%,100%by medium pressure columns and MCI columns.Then,the contents of flavonoids and phenolic acids and the antibacterial activities in different components were measured,20%,60%,80%components have better antibacterial activities.3.The main active ingrediens of 20%,60%,80%were identified respectively as gallic acid,quercitrin,and quercetin by using high-performance liquid chromatography and mass spectrometry,and their acrtibacterial activities were also measured.The results show that gallic acid,quercitrin,and quercetin are main active ingredients of 20%,60%,80%.4.To investigate inhibittory activities of different polar solvent extracts from Polygonum capitatum on the a-glucosidase,the IC50 value of inhibittory activity of the different polar solvent extracts on the a-glucosidase were measured.Sequence:n-butanol phase<ethyl acetate phase<crude extract<chlorine phase<petroleum ether phase<aqueous phase.The n-butanol phase had the best a-glucosidase inhibittory activity,followed ethyl acetate,the weakest was aqueous phase.Components of n-butanol phase were analyzed by HPLC.The results condicated:quertrin and quercetion are active ingredients in the n-butanol phase on a-glucosidase inhibitory.