Study On The Chemical Constituents And Bioactivity Of Homalomena Occulta And Taxus Chinensis

This thesis describes the phytochemical investigation of the rhizomes of Homalomena occulta grew in Guangdong province,parts of the compounds isolated from 95%ethanol extract were evaluated for their cytotoxic activity,antibacterial activities and lipid-lowering activity.Furthermore,the effect and mechanism of of the attenuated Taxus chihensis extract on chronic obstructive pulmonary(COPD)murine model were evaluated.Nineteen compounds were isolated from 95%ethanol extract of the rhizomes of Homalomena occulta by means of column chromatography(CC),preparative thin layer chromatography(PTLC),and recrystallization etc.In combination with the spectroscopic data from literature,the structure of all compounds have been identified as oplodiol(1),spathulenol(2),1β,4β,6a-trihydroxy-eudesmane(3).1β,4β,7α-trihydroxyeudesmane(4),homalomenol J(5),homalomenol M(6).4β,10β-dihydroxyaromadendrane(7),caryolane-1β,9β-diol(8),homalomenol B(9),dihydroxymaaliane(10),aromadendranediol(11),homalomenol A(12),1β,4β,7β-eudesmanetriol(13),eudesm-7-en-4-ol(14),tricyclohumuladiol(15).1β,6α-dihydroxyeudesman-4-one(16),linalool(17),sesamin(18),β-sitosterol(19).Among them,compounds dihydroxymaaliane(10),eudesm-7-en-4-ol(14),tricyclohumuladiol(15),and 1β,6α-dihydroxyeudesman-4-one(16)were obtained from the genus Homalomena for the first time.Compound sesamin(18)was obtained from the Homalomena occulta for the first time.Furthermore,fifteen compounds were evaluated for their cytotoxic activity and lipid-lowering activity,and six compounds were used for screening of antibacterial activities.Among these compounds,A mixture of 4β,10β-dihydroxyaromadendrane(7)and caryolane-1β,9β-diol(8)showed cytotoxic activity against AML-12 cell line,compound dihydroxymaaliane(10)showed significant lipid-lowering activity in AML-12 cell line,compound oplodiol(1)and compound spathulenol(2)showed antibacterial activity against Helicobacter pylori.In addition,the effect and action mechanism of attenuated Taxus chinensis extract on chronic obstructive pulmona ry(COPD)murine model were studied.By collecting the bronchoalveolar lavage fluid(BALF)and lung tissues,the total white cell count in BALF were performed.The inflammatory cells i nfiltration was observed by HE staining and AB/PAS staining for lung biopsy.The SOD,GSH activity,MDA content and the expression of cytokine(KC,MIP-2,TNF-α)in lung were tested.Myeloperoxidase(MPO)activity of lung were also be determined.As a result,the extract of attenuated Taxus chinensis can decrease the content of white cell in BALF,and showed a inhibitory effect on formation of lung bullae and inflammatory cells around the airway,perivascular and tissue space.It can increase the activity of SOD and the content of GSH,and also can decrease the content of MIP-2 and significantly inhibit the action of inflammatory factors such as TNF-α and KC.Also,the extract of attenuated Taxus showed the effect of inhibiting MPO activity at low dose.Therefore,the extract of attenuated Taxus can inhibit the pulmonary inflammation and mucus secretion in COPD murine model by decreasing the expression of cytokine(KC,MIP-2,TNF-α)and the activity of MPO and increasing the activity of SOD and the content of GSH.In summary,the extract of attenuated Taxus chinensis extract showed therapeutic effect on COPD murine model.