| Dendrobium was used as a famous traditional Chinese medicine, which possessed the functions as nourishing yin and clearing heat, clearing liver and improving eyesight, and gastrointestinal conditioning. And modern pharmacology has also approved that it posses bioactivities as antitumor, antioxidant, antimicrobial, improve immunity and neuroprotective. Phytochmical investigation on the Dendrobium has led to the isolation of a series of components including phenolic, phenanthrenes, bibenzyls, and alkaloids. Dendrobium hainanense is a plant growing in the southern region of China (Guangdong, Hainan and Hong kong), and as a member of Dendrobium family there were few previous record of chemical examinations on it. In order to search for the bioavtive components from Dendrobium, chemical components and their biological activities on the aerial part of D. hainanense has been studied.By means of various of chromatographic techniques,38compounds had been isolated. And their structures were identified by spectral analysis including NMR and MS data as2,6-dimethoxy-Ρ-benzoquinone (1),(+)-dehydrovomifoliol (2), blumenol A (3),4-hydroxy methyl-2-methoxy-phenol (4), alatusol D (5),threo-8s-7-methoxysyringylglycerol (6),(Ε)-coniferyl aldehyde (7), sinapicaldehyde (8), Ε-Ρ-hydroxy cinnamic acid (9), vanillin (10), syringaldehyde (11),Ρ-hydroxypheny lpropionic methyl ester (12),2,6-dimthoxy-4-allyphenol (13),4-allyl-2,6-dimethoxyphenyl glucoside (14),3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-1-propanone (15), methyl hydrogen succinate (16),(3S,6S)-6,7-dihydroxy-6,7-dihydrolinalool (17),(3S,6R)-6,7-dihydroxy-6,7-dihydrolinalool (18),4-acetonyl-3,5-dimeth-oxy-Ρ-quinol (19), dihydroconiferyl dihydro-Ρ-coumarate (20), hainansol (21), erianthridin (22),3-hydroxy-2,4,7-trimethoxy-9,10-dihydro-phenanthrene (23),3,7-dihydroxy-2,4-dimethoxy-9,10-dihydro-phenanthrene (24),2,7-dihydroxy-3,4-dimethoxy-phenanthrene (25),3,7-dihydroxy-2,4-dimethoxy-phenanthrene,(26),3-hydroxy-2,4,7-trimethoxy-phenanthrene (27),3,4,7-trihydroxy-2-methoxy-phenanthrene (28), hainansol B (29), hainansol C (30), denchrysan A (31), nobilone (32),(+)-syringaresinol (33), syringaresinol-4’-Ο-β-D-monoglucoside (34),(+)-lyoniresinol (35), Ε-ferulic acid hexacosyl ester (36),β-sitostero (37), and β-daucosterol (38). Compound1-21were phenolics, and compound21was a new compound, compounds22-30were belonged to phenanthrene, and compound29and30were new compounds. All of the compounds were isolated from D. hainanense for the first time.The antibacterial activites of compound1-38were measured by the method of paper disco diffusion. The result indicated that compounds1,4,6,7,10,12,16,20,22,24,25,26and27had a certain inhibitory activity against Staphylococcu. aureus. Compounds1,6,19,20,21,24,25,26and32showed inhibitory activity against Canidia Albicans. Compounds1,3,5,6,9,12,16,20,21,22,24,25and26had activities against Ralstonia. Solanaceanum. Cytotoxicity of all the compounds was assayed by MTT method, and the result showed that compounds22,26,28, and35had cytotoxicities against K562as well as compound25and28against SGC-7901. The acetylcholinesterase inhibitory activity of all the compounds was tested according the method of Ellman, and the result revealed that compounds4,22,25,26,27,28,32and35had weak activity.In this thesis, chemical constituents and their biology activities from Dendrobium hainanense were investigated. The compounds isolated from the plant enriched the structure type of the Dendrobium, and the bioassay results revealed that some of the compounds possessed anti-becteria, cytotoxic, and neuroprotective activities, which suggested that D. hainanense was a very potential medicinal resource to be exploited. |
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