Studies On The Chemical Constituents Of Saussurea Kansuensis Hand.-Mazz. And Chemosystematics Study On Saussurea DC.

Saussurea kansuensis Hand.-Mazz,perennial stemless herbs belongs to the genus Saussurea DC in the Compositae.It is an endemic species known only from Gannan(eastern edge of Qinhai-Tibet Plateau,Gansu province)where it distributed at the altitudes from 3600m to 3700m in Xigu and Mingshan.S.kansuensis Hand.-Mazz, has long been used for traditional Chinese medicine in China with the effects of relieving internal heat and pain,harmonizing the circulation of menstrual,curing gynecology diseases.We studied the chemical constituents of S.kansuensis Hand.-Mazz. systematically in Gansu province for the first time.Fourteen chemical compounds were isolated from Pet.Et.and EtOAc.sections separately by means of solvent partition,silica gel column chromatography(CC),preparative thin layer chromatography(TLC)and recrystallization etc.The structures of these compounds were elucidated by spectroscopic methods:IR,MS and 1D NMR(¹H NMR,¹³C NMR,DEPT).One of them was preliminary determined as new compound named 1β,3β-dihydroxyurs- 9(11),12-diene-hexadecanoate(1)and need further study. 8α-11β-dihydroxy-1(10),-guaiadiene-12,6-olide-2-one-O-β-D-glucopyranoside(2),11,12,13-trihydroxy-4,(15),8-eudesmdiene-8-one(3),3-hydroxy-1(10),3-guaiadiene - 12,6-olide-2-one(4),10β-dihydroxy-11αH-guaia-4(15)-ene-12,6α-olide (5),3-hydroxy-1(10),4-germadiene- 12,6-olide(6)urs-2α,3β,19α,30-tetrahydroxy-12-ene-23,28-dioicacid- 28-0-(6'-O-methyl-β-D-glucopyranosyl)(7),urs-2α,3β,19α,24-tetrahydroxy-12-ene- 28-oic ester(8),3β,22α-dihydroxyl-20α, 21α-epoxy-taraxasta(9),stigmast-5-ene-3β,7α-diol(10),β-daucosterol(11),ergosterol peroxide(12),luteolin(13)andβ-sitosterol(14)。The essential oils of S.kansuensis Hand.-Mazz.were obtained by hydrodistillation and subjected to detailed GC/MS analysis in order to determine possible similarities among 9 populations and also the differences in their chemical compositions from a chemotaxonomic point of view.A total of 69 compositions were identified and indicated that sesquiterpene hydrocarbons and oxygenated sesquiterpenes were the main components.Cluster analysis and principal component analysis(PCA)of identified components both grouped oils into three clusters which corresponding three transitional chemotype:carophyllene oxide/cis,cis,cis-7,10,13-hexadecatrienal,carophyllene oxide/ carophyllene/deltacyclene and carophyllene oxide/3H-3a,7-methanoazulene,2,4,5,6,7,8-hexahydro- 1,4,9,9,-tetramethyl.No significant differences in chemical constituents of essential oils were observed among populations in different habitats.The similarities and also the differences in their chemical compositions were coexisting.The antibacterial effect of essential oil was evaluated preliminary.It showed stronger antibacterial activity against Bacillus subtilis at the concentration of 10 mg/ml comparing with Penicillin.It also presented antibacterial activity against Escherichia coli at the concentration of 10 mg/ml.However,no antibacterial activity was observed against Staphylococcus aureus.The distribution of Saussurea DC.in Gansu province was studied and the summarization of the chemical and pharmacological study of this genus was investigated.This work is the first chemosystematics study based on the current results of chemical studies and the investigations of the floristic study of Saussurea DC.The results showed that the five subgenres established based on the morphological characters confirm with the division based on different chemical components and their structure.However,the main chemical components in sect. Cyathidium(Lindl.ex Royle)Ling and sect.Laguranthera(C.A.Mey.Ex Endl.) Lipsch.were guaianolide,eudesmane and pentacyclic triterpenoids while the main chemical components in sect.Saussurea were quite different in subgen.Saussurea. We needed more data about chemical components of other species in Saussurea DC. Subgen.Eriocoryne(DC.)Hook.f.and subgen.Amphilaena(Stschegl.)Lipsch.were dominated with flavonoids as their main chemical components.Especially in Subgen. Eriocoryne(DC.)Hook.f.,dominated with luteolin and apigenin(floavones)which denoted more evolutional comparing with kaempferol and quercetin(floavonols)in subgen.Amphilaena(Stschegl.)Lipsch.The centre of abundance of the two subgenres is Hengduang-Himalaya which was affected greatly by the lift of Qinghai-Tibetan Plateau in late Tertiary period and early Quaternary.Related to the results of floristic study of Saussurea DC.,we preliminarily concluded that the phylogenetic relationship in Saussurea DC.was Subgen.Eriocoryne(DC.)Hook.f.—Subgen.Amphilaena (Stschegl.)Lipsch.—Subgen.Theodorea(Cass.)Lipsch.—Subgen.Florovia(DC.) Lipsch.—Subgen Saussurea.