| Dipsaci Radix, the roots of Dipsacus asper Wall. (Dipsacaceae), have been used as a tonic and analgesic agent in traditional Chinese medicine (TCM) for the treatment of osteoporosis, low back pain, knee pain, bone fractures and abortion. The resources used to be mainly from Sichuan province. But more medicinal materials were collected from Yunnan and Guizhou nowadays, with the growth of market demand. Many regions have turned to cultivature. Furthermore, as a perennial herb, the roots of D. asper in market were much thinner than before. The quality was on the downgrade with the decreasing of natural resources. Evaluating this medical material was studied in this dissertationFirstly, chemical composition was studied. The five new compounds were named as dipsacus saponin J (4), dipsacus saponin K (8), dipsanoside J (11), dipsanoside K (12) and dipsanoside L (13). Structures of the known compounds were identified as HN saponin F (1), dipsacus asponin VI (2). macranthoidin A (3), dipsacus saponinⅫ(5), dipsacus saponin X (6),3-O-β-D-xylopyranosyl(1→4)-β-D-glucopyranosyl-(1→4)]-[α-L-rhamnopyranosyl(1→3)]-β-D-glucopyranosyl(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-hederagenin-28-O-β-D-glucopyranoside (7), sweroside (10), dipsanoside B (14), dipsanoside A (15), loganic acid (19) respectivelySecondly, in vitro activities of triterpenoid saponins(l-8) was studied. Compounds 5 and 6 could significantly stimulate UMR106 cell proliferation and all tested saponins(2, 3,5-7) could increase ALP activities in UMR106 cell at the concentration of 4μM. Compounds 1-8 had no cytotoxicity against A375, BGC823, MCF7, SW1990 and HEPG2 cells.To evaluate the quality of D.asper, a HILIC-HPLC-UV method was developed to determine the contents of dipsacus saponinⅥ,ⅩandⅫ, which were highest saponins in this plant. Furthermore, a HPLC-DAD method was established for simultaneous determination of six iridoid glycosides(loganic acid,19; loganin:sweroside.10: dipsanoside L.13. dipsanoside B,14. dipsanoside A.15.) and two phenolic acids (chlorogenic acid and an unknown compound.18) in 34 batches of samples collected in the field and 26 batches from markets. Principal component analysis (PCA) were applied to analysis the samples and chemical characteristics were proposed.Contents of dipsacus saponinⅥ,Ⅹ,Ⅻand loganic acid were the most important indicators for quality evaluation of Dipsaci Radix. Dipsanoside A and chlorogenic acid were meaningful compound as well. Samples from Yunnan contained the highest total saponins. Followed by Sichuan. The contents in Hubei and guizhou were poor. The descending order of total contents of iridoid glycosides is Guizhou, Sichuan, Hubei and Yunnan. The content of phenolic acids in samples from Guizhou is much higher than other regions.Each of the main producing areas has its own characteristics in chemical composition. Samples from Yunnan are characterized by highest level of dipsacus saponin VI. Samples from Sichuan are characterized by highest level of dipsacus saponin X. Although dipsacus saponin VI was low in Hubei and Guizhou, dipsanoside A was rich in samples from them. Guizhou's samples are characterized by the highest level of chlorogenic acid and loganin.Multiple linear regression analyses was applied to evaluation of the most important ecological climatic factors on quality of Dipsaci Radix. As a result, the most important one is altitude. The total contents of tested compounds would be higher with the increase of elevation. Secondly, annual rainfall and sunshine hours had positive impacts on contents of main constituents. The impact of genetic was important as well.Dipsacus saponins were mainly distributed in the cortex of the roots, but iridoid glycosides were mainly in the xylem. This can explain that total saponins were lower in thick roots than that of thin roots, but total iridoid glycosides had a opposite situation. Reed head and stem residues, with much lower contents of various chemical components. should be removed during the processing. Fibrous roots contain low iridoid glycosides. but rich saponins, should be used reasonablely.The changes of chemical composition in roots of D. asper were irregular by different drying methods. It was probably caused of complex affecting factors on the activity of glycosidase.Six species of Dipsacus was collected and quantified. They were D. asper, D. japonicas, D. chinensis, D. lijigensis. D. yulongensis, D. kangdingensis. All tested six species contained simple Iridoid glycosides such as loganic acid, loganin. sweroside and polymer such as dipsanoside A and B. The contents ratio of dipsacus saponinⅥ,Ⅹ,Ⅻcan be used for species classification.D. japonicas had low content of dipsacus saponinⅫ, and no dipsacus saponinⅥand X. D. chinensis had low content of total saponins, but the ratio of saponin XII was the highest. D. asper had higher content of total saponins, and the ratio of saponin XII is the lowest. D. yulongensis and D. kangdingensis were similar to D. asper, which supported the 2 species affiliated with D. asper.
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