- 學位論文
白木香莖皮之化學成分及生物活性之研究
Studies on the Chemical Constituents and Biological Activities from the Stem Barks of Aquilaria sinensis
摘要
白木香為瑞香科之常綠喬木，為中國特有種植物。對台灣產植物及中草藥進行抗發炎活性篩選，其中白木香為活性植物之一。 由白木香莖皮之EtOAc可溶部，目前已分離出2個新的flavones : 4'-O-geranyltricin (1)和3'-O-geranylpolloin (2)及1個新的2-(2-phenyl- ethyl)-4H-chromen-4-one : 7-hydroxyl-6-methoxy-2-(2- phenylethyl)chro- mone (3)，以及21個已知化合物。已知化合物中包括6個flavones: tricin (4), 5-hydroxy-7,3′,4′-trimethoxyflavone (5), velutin (6), apigenin 7,4′- dimethyl ether (7), 3′-hydroxygenkwanin (8)及sakuranetin (9); 1個2-(2-phenylethyl)-4H-chromen-4-one: 6,7-dimethoxy-2-(2-phenylethyl)- chromone (10); 1個lignan: (-)-syringaresinol (11); 1個??-carboline生物鹼: taraxacine A (12); 4個benzenoids: methyl 3,4-dihydroxybenzoate (13), vanillic acid (14), docosyl caffeate (15)及docosyl trans-ferulate (16); 3個steroids: ??-sitosteone (17), ??-sitosterol (18)及ergosta-4,6,8(14),22- tetraen-3-one (19); 1個diterpene: trans-phytol (20); 1個 ??-tocopheroids: ??-tocopherol (21)及??-tocospiros A (22); 1個cyclohex-2-en-1-one: blumenol A (23); 1個benzoquinone: 2,6-dimethoxy-p-benzoquinone (24)。上述化合物之結構，經由各種圖譜分析及文獻數據比對予以確認。 目前分離所得到的化合物中， 4′-O-geranyltricin (1), 3′-O-geranyl- polloin (2)及3′-hydroxygenkwanin (8)在30 μM濃度下，對於lipopolysaccharide (LPS)誘導巨噬細胞(macrophages)進而活化NF-?羠，具有顯著的抑制活性，其抑制NF-?羠活化之百分比分別為61.4 ± 2.1 %, 68.3 ± 3.4 %及62.2 ± 5.9 %。另外，5-hydroxy-7,3′,4′-trimethoxyflavone (5), velutin (6), 3′-hydroxygenkwanin (8), sakuranetin (9)及vanillic acid (14)對於formyl-L-methionyl-L-leuckyl-L-phenyl-alanine/cytochalasin B (fMLP/CB)誘導人類嗜中性白血球產生超氧陰離子(O2•–)，具有良好的抑制活性，其IC50 值分別為1.54 ± 0.31, 0.56 ± 0.11, 2.39 ± 0.23, 0.50 ± 0.05及6.61 ± 1.01?n?慊/ml。此外velutin (6), 3′-hydroxygenkwanin (8), vanillic acid (14)及ergosta-4,6,8(14),22- tetraen-3-one (19) 對於fMLP/ CB誘導人類嗜中性白血球釋放彈性蛋白酶(elastase)，具有良好的抑制活性，其IC50 值分別為1.34 ± 0.04?z?n1.37 ± 0.19, 6.71 ± 0.42及5.98 ± 1.47?慊/ml。
並列摘要
Aquilaria sinensis (Lour.) Gilg. (Thymelaeaceae) is an evergreen tree and endemic to China. In our studies on the anti-inflammatory constituents of Formosan plants and Chinese herbal medicine, many species have been screened for in vitro anti-inflammatory activity, and A. sinensis has been found to be one of the active species. Investigation of EtOAc-soluble fraction of the stem bark of A. sinensis has led to the isolation of two new flavones, 4'-O-geranyltricin (1) and 3'-O-geranylpolloin (2), a new 2-(2-phenylethyl)-4H-chromen-4-one derivative, 7-hydroxyl-6-methoxy-2-(2-phenylethyl)chromone (3), and 21 known compounds, including six flavones, tricin (4), 5-hydroxy-7,3′,4′- trimethoxyflavone (5), velutin (6), apigenin 7,4′-dimethyl ether (7), 3′-hydroxygenkwanin (8), and sakuranetin (9), a 2-(2-phenylethyl)-4H- chromen-4-one, 6,7-dimethoxy-2-(2-phenylethyl)chromone (10), a lignin, (-)-syringaresinol (11), a ??-carboline alkaloid, taraxacine A (12), four be- nzenoids, methyl 3,4-dihydroxybenzoate (13), vanillic acid (14), docosyl caffeate (15), and docosyl trans-ferulate (16), three steroids, ??-sitosteone (17), ??-sitosterol (18), and ergosta-4,6,8(14),22-tetraen-3-one (19), a di- terpene, trans-phytol (20), two ??-tocopheroids, ??-tocopherol (21) and ??-tocospiros A (22), a cyclohex-2-en-1-one, blumenol A (23), and a ben- zoquinone, 2,6-dimethoxy-p-benzoquinone (24). The structures of all isolates were determined through spectral analyses and comparison of their physical and spectral data with literatures. Among the isolated compounds, 4′-O-geranyltricin (1), 3′-O- geranylpolloin (2), and 3′-hydroxygenkwanin (8) exhibited inhibition against lipopolysaccharide (LPS)-induced NF-?羠 activation by macro- phages at 30 ?嵱 with inhibition of NF-?羠 activation of 61.4 ± 2.1 %, 68.3 ± 3.4 %, and 62.2 ± 5.9 %, respectively. Furthermore, 5-hydroxy- 7,3′,4′-trimethoxyflavone (5), velutin (6), 3′-hydroxygenkwanin (8), sakuranetin (9), and vanillic acid (14) exhibited potent inhibition against fMLP/CB-induced superoxide (O2•–) production with IC50 values of 1.54 ± 0.31, 0.56 ± 0.11, 2.39 ± 0.23, 0.50 ± 0.05 and 6.61 ± 1.01 ?慊/ml, respectively. In addition, velutin (6), 3′-hydroxygenkwanin (8), vanillic acid (14), and ergosta-4,6,8(14),22-tetraen-3-one (19) exhibited potent inhibition against fMLP/CB-induced elastase release with IC50 value of 1.34 ± 0.04, 1.37 ± 0.19, 6.71 ± 0.42 and 5.98 ± 1.47 ?n?慊/ml, respectively.