Studies On The Chemical Constituents And Their Bioactivities Of Four Medicinal Plants

Chemical components and bioactivities of some compounds of four medicinal plants were researched systematically, including three Compositae species(Vernonia anthelmintica Willd, Ligularia achyrotricha (Diels) Ling, and Senecio chrysanthemoides DC.) and one southern plants belonging to the family of Elaeocarpus(Elaeocarpus sphaericus). V. anthelmintica Willd have been used for the treatment of asthma, hiccough, inflammatory swellings, sores, and itching of the eyes. The roots and leaves of Z. achyrotricha have heat-clearing and detoxic effects and have been used as an important species of traditional Tibetan medicine for a long time to treat dermatosis, diphtheria, and pestilence. S. chrysanthemoides DC. posses efficacy of invigoration the circulation of blood and soothing pain. E. sphaericus is used also as a traditional Chinese herbal medicine due to its calming effect on central nervous system and having a certain effect on the treatment of moderate chronic pain.94 compounds were isolated from these plants by means of silica gel column chromatography (CC), preparative thin layer chromatography (PTLC), high performance liquid chromatography (HPLC) and recrystallization etc. Then various spectroscopic methods including IR, UV, CD, EIMS, ESIMS, HRESIMS,1HNMR,13C NMR, DEPT, NOEd,'H-'H COSY, HSQC, HMBC, NOESY, single-crystal X-ray crystallography and CD exciton chirality method were used to elucidate the structures of 90 compounds, among which there were sixteen new compounds.40 compounds were isolated from the aerial parts of V. anthelmintica Willd, and 38 compounds (including 12 new compounds) of them were elucidated. Their structures were determined as steroids, steroidal glycosides, triterpenoids, flavonoids, sesquiterpenoids, etc.25 compounds (including 1 new compound) were isolated and 24 were elucidated from the roots of Z. achyrotricha. The structures of them included pyrrolizidine alkaloid, lignans, coniferyl and sinapyl alcohol derivatives, steroids, triterpenoids, flavonoids, etc.7 compounds were separated from S. chrysanthemoides.22 compounds (including 3 new compounds) were obtained and 21 were elucidated from the aerial parts of E. sphaericus. The structures of these compounds were confirmed as alkaloid, triterpenoids, steroids, Vitamin E, ubiquinone, etc. Moreover, the absolute configurations of compounds Va 1- Va 12 were deduced using single-crystal X-ray diffraction and the CD exciton chirality method.The bioactivities of some of these compounds were also studied. Firstly, micro-broth dilution method was used to evaluate the antimicrobial activity of steroids from the aerial parts of V. anthelmintica Willd(Va 1,Va 5,Va 7,Va 9,Va 13,Va15,Va 16,Va 19 and Va 20) against Staphylococcus aureus. Bacillus cereus. Bacillus subtilis and Escherichia coli. Compound Va 13 showed antibacterial activity against these bacteria with MICs ranging from 3.15 to 15.5μg/mL. We also examined their effects on estrogen biosynthesis in human ovarian granulosa-like KGN cells. Va 13 showed the ability to promote estrogen biosynthesis with ECso of 56.95μg/mL. Secondly, compound La 1 from the roots of L. achyrotricha exhibited moderate activity against HL-60 and SMMC-7721 cells. Lastly, the AChE inhibitory activities for three alkaloids Es 8-Es 10 from the aerial parts of E.sphaericus were tested.Finally, the chemical constituents and their activities of the species of genus Vernonia reported from 2004 were reviewed in this dissertation. We hoped this review was useful to chemotaxonomy of subtribe Vernonia.The results of this dissertation will be supplement for the research on phytochemistry, the relationship of structure and activity, biological activity, chemotaxonomy and screening new medicines. Moreover, they are meaningful in providing scientific evidence to further development and utilization of traditional natural medicine resources.