Pharmacognostic Studies Of Polygonum Cuspidatum Sieb. Et Zucc.(Polygonaceae)

Polygonum cuspidatum Sieb. et Zucc., distributed mainly in temperate Asia, are thickets in valleys, field margins, mountain slopes in many areas in China. P. cuspidatum has been used in many Asian countries as traditional medicinal herbs for centuries. The root and radix of P. cuspidatum is a well-known Chinese herbal medicine, and nowadays it is recorded in the Pharmacopaeia of the People’s Republic of China. It is traditionally used for dispelling wind-evil, damp elimination, eliminating stasis to active blood circulation, analgesic therapy, relieving cough and reducing sputum. P. cuspidatum leaves are traditionally used for the treatment of rheumatism, joint pain, snakebites and skin disease. It is recorded in "Chiu Huang Pen Ts’ao" as an edible wild herb and is a popular edible wild herb in many areas in China, such as Fujian, Jiangxi, Yunnan, and Henan province.In the present study, the preliminary pharmacological study of major compounds, the identification of P. cuspidatum and its adulterants, the quality control method of root and radix of P. cuspidatum were studied. Meanwhile, P. cuspidatum leaves were also studied for further development:the identification of chemical constituents, the content determination, and the antioxidant activities.In vitro activities of main components were studied. Hydroxyanthraquinones in P. cuspidatum, such as emodin, physcion, citreorosein, aloeemodin, chrysophanol, and rhein were main bioactive compounds for improving glucose uptake in HepG2cell. However, their glycosides showed no activities. Therefore, their hydroxyl groups were deduced to be essential for activities. Compounds with different structure types in P. cuspidatum showed inhibition effects against lipid accumulation. They are polydation, hyperin, emodin-8-O-glucoside, rhein, and aloeemodin.The psbA-trnH sequence was used as DNA Barcode for distinguish twenty four samples of P. cuspidatum (roots:14, leaves:10) and their adulterants. Intraspecific variation was analyzed. P. cuspidatum samples and other Polygonaceae herbs were discriminated using BLAST, nearest distance, and NJ tree methods. There were a low degree of intraspecific variation, and a relatively high degree of interspecific variation for successful species identification.A UPLC-PDA method was developed for simultaneous quantitative determination of5compounds in38root and radix samples of P. cuspidatum collected from markets or habitats. The UPLC fingerprint was also used for quality control. Common pattern of chromatograph was established, and similarity analysis, hierarchical cluster analysis and principal component analysis were applied for further evaluation. Physcion contents in22samples form Shaanxi, Hubei and Henan were relatively higher; resveratrol contents in7samples from Hunan and Guangxi were relatively higher, while polydatin contents were obviously lower; polydatin and emodin contents in9samples from Anhui and Jiangsu were relatively higher.The HPLC-DAD-MSn method was developed to study the major components from P. cuspidatum leaves. Twenty-eight compounds were separated, and15of them were tentatively characterized based on their UV and MS spectra. Eight compounds were further ascertained by comparison with the corresponding reference compounds, and quantified in9batches of leaf samples. The antioxidants were screened by DPPH-HPLC and lipid peroxidation-HPLC method. The antioxidant abilities were evaluated for the leaves and compounds as well. The possible relationships among the compound content, antioxidant abilities, collection time, and resource regions were discussed.