Terpenoidal constituents of Eucalyptus loxophleba ssp. lissophloia

Context: Eucalyptus has been a source of a number of biologically active compounds. The anti-leishmanial activity of terpenoids from Eucalyptus loxophleba (Benth.) ssp. lissophloia (Myrtaceae) has not yet been investigated.

Objective: Isolation of the terpenoidal constituents for evaluation of in vitro anti-leishmanial activity against the Leishmania donovani (Dd8 strain) promastigotes.

Materials and methods: The chloroform–methanol (8:2) extract of dried leaves of Eucalyptus loxophleba was used to isolate terpenoidal constituents employing solvent partitioning, column chromatography and preparative high performance liquid chromatography and characterized from spectral data. The anti-leishmanial activity of the isolated compounds was tested in vitro using an Alamar blue assay against a culture of L. donovani (Dd8 strain) promastigotes.

Results: Two new naturally occurring triterpenes, named loxanic acid and 3-acetyl loxanic acid together with four known ursane triterpenoids and one bis-monoterpene glycoside, cuniloside B isolated from the leaves showed anti-leishmanial activity (IC₅₀ 133 to 235 μM) against the promastigotes of the tested strain.

Conclusion: The terpenes isolated from the leaves of E. loxophleba showed moderate anti-leishmanial activity.     

Stimulation of glucose uptake by triterpenoids from Weigela subsessilis

Four ursane‐type triterpenoids, corosolic acid (1), ilekudinol B (2), ursolic acid (3) and pomolic acid (4), were isolated from an EtOAc‐soluble extract of the leaves of Weigela subsessilis. These bioactive compounds were evaluated for their glucose uptake activity and produced moderate to strong enhancement both in basal‐ and insulin‐stimulated L6 muscle cells. In particular, corosolic acid exhibited the most potent activity, increasing uptake by basal‐ and insulin‐stimulated myotubes by 2.63‐ and 3.33‐fold, respectively; ilekudinol B produced 1.6‐ and 2.9‐fold, ursolic acid produced 1.84‐ and 2.64‐fold, and pomolic acid produced 1.6‐ and 2.8‐fold increases. No cytotoxicities were observed for corosolic acid, ursolic acid and ilekudinol B in myoblasts, while pomolic acid at doses of 25 and 50 µm reduced cell viability by 19% and 21.8% upon 24 h treatment and by 48.6% and 54.1% upon 48 h treatment, respectively. These results suggest that ursane‐type triterpenoids from W. subsessilis might enhance glucose uptake by acting as insulin mimics and as insulin sensitizers and that they could be useful as nontoxic diabetes treatment agents. Copyright © 2009 John Wiley & Sons, Ltd.     

高山地榆中3个乌苏烷型三萜成分

目的研究高山地榆中的乌苏烷型三萜。方法利用反复硅胶柱色谱分离纯化,通过理化常数和波谱分析确定结构。结果从高山地榆根茎的乙酸乙酯部分分离得到3个乌苏烷型三萜类化合物。结论经鉴定,3个化合物分别为乌苏酸甲酯(Ⅰ)、2α,3α,19-αtrihydroxyurs-12-en-28-oic acid(Ⅱ),2α,3-αdihydroxyursa-12,19(29)-dien-28-oic acid(Ⅲ),均为首次从该植物中分离得到。     

番石榴果实中三萜类成分研究

目的:研究番石榴果实的化学成分.方法:采用各种色谱技术分离,波谱法进行结构鉴定.结果:从番石榴果实中分离得到9个乌苏烷型三萜类化合物:乌苏酸(1),1β,3β-二羟基乌苏烷-12烯-28-酸(2),2α,3β-二羟基-12-烯-28-乌苏酸(3),3β,19α-二羟基-12-烯-28-乌苏酸(4),19α-羟基-12-烯-28-乌苏酸-3-O-α-L-阿拉伯吡喃糖(5),3β,23-二羟基-12-烯-28-乌苏酸(6),3β,19α,23-三羟基-12-烯-28-乌苏酸(7),2α,3β,19α,23-四羟基-12-烯-28-乌苏酸(8),3α,19α,23,24-四羟基-12-烯-28乌苏酸(9).结论:化合物2,5-9为首次在该植物中分离得到.     

天然五环三萜及其衍生物抗心脑血管疾病的研究进展

心脑血管疾病是我国成年人群首要致死病因,且发病率呈上升和年轻化趋势,运用中药治疗心脑血管疾病十分必要。天然产物是治疗心脑血管药物的重要来源。三萜类化合物是植物体内重要的次生代谢产物,具有广泛的生物活性,其中五环三萜类表现出明显的抗炎、抗肿瘤、抗病毒等药理作用。近年来,越来越多的研究集中在五环三萜类化合物抗心脑血管疾病领域,对其结构进行衍生化从而提升活性、改善药性的研究也越发深入。通过查阅国内外五环三萜类化合物及其衍生物近10年的文献专利报道,综述了齐墩果烷、乌苏烷、羽扇豆烷、木栓烷4种类型五环三萜类化合物及其衍生物抗心脑血管疾病的研究进展,为治疗心脑血管疾病药物的研发提供依据和参考。     

Ursane Triterpenoids Inhibit Atherosclerosis and Xanthoma in LDL Receptor Knockout Mice

Introduction In order to determine the mechanism of triterpenes, a class of secondary metabolites in plants, in modulating progression of vascular atherosclerotic lesions, we isolated three ursane triterpenoids (euscaphic acid, tormentic acid and 2α-hydroxyursolic acid) from aerial part of Salvia miltirrhiza Bge. and fed LDLr^−/− mice the isolated compounds at a dose of 10 mg/kg p.o. for 24 weeks. Materials and methods The treated mice were raised with a cholesterol-enriched (1.25%) diet. Implying serum and aorta MCP-1 analysis, we found that all mice treated with the compounds exhibited a significant reduction of whole body and vascular inflammation. Results The reduction of macrophage cells’ number in aortic atherosclerotic lesions suggests that triterpenes treatment results in the development of a more stable plaque phenotype. Analysis of the structure-activity relationships demonstrates that compounds with a β-orientated hydrogen-bond forming group at C-3 exhibit more potent anti-atherogenic effect than the α-counterpart on the development of atherosclerosis and xanthoma. However, the biological activities of the compounds are significantly reduced when they have C-19 hydrogen-bonds. Conclusion These Results suggest that down-regulation of MCP-1 is the main mechanism for antiatherogenic activity of triterpenes and MCP-1 might play important roles in the development of atherosclerosis and xanthoma.     

岗梅根的化学成分研究

目的 研究岗梅Ilex asprella根的化学成分.方法 采用硅胶柱色谱、反相硅胶柱色谱等方法进行分离和纯化,并结合其理化性质及波谱数据鉴定化合物结构.结果 确定了12个化合物的结构,分别为乌索-12-烯-3β,28-二醇,3-乙酸酯(1)、β-谷甾醇(2)、赪酮甾醇(3)、28-nor-19βH,20αH-ursa-12,17-dien-3-ol (4)、randialic acid B(5)、19-去氢乌苏酸(6)、熊果酸(7)、坡模酸(8)、3-O-β-D-木糖基-3β-O-28-缺失-12,17(18)-二烯乌苏烷(9)、β-胡萝卜苷(10)、冬青苷B(11)、赪酮甾醇-3-O-β-D-葡萄糖苷(12).结论 化合物9为新化合物,命名为岗梅苷H.化合物1、2、4、7、8、10为首次从该植物中分离得到.     

山绿茶中Ilexgenin A对HepG2肿瘤细胞抑制作用的研究

目的:探讨3β,19α-二羟基乌苏-12-烯-24,28-二羧酸(IA)对肝癌细胞株HepG2细胞周期、凋亡的影响及其作用机制。方法:人肝癌细胞株HepG2以IA 20,40,60,80 g·L-1作用不同的时间后,分别使用四甲基偶氮唑蓝比色法(MTT),吖啶橙(AO)荧光染色法,免疫细胞化学SP法,流式细胞术检测HepG2细胞的增殖抑制情况,细胞周期和凋亡的形态学变化,以及细胞内凋亡相关蛋白Bcl-2,Bax表达的变化。结果:IA对HepG2细胞增殖有抑制作用,其作用随着药物浓度和作用时间的增加而增强。IA作用24 h后HepG2细胞周期的主要特点是大量细胞累积于G1期,进入S期的细胞减少,IA能够诱导HepG2细胞凋亡,IA(40,60,80 g·L-1)经过24 h作用后,细胞凋亡率分别为7.89%,8.37%,9.93%,AO染色观察到大量凋亡细胞,凋亡细胞染色减弱、荧光较暗、呈均匀一致的圆状或固缩状,细胞内Bcl-2的表达随着药物浓度增加逐渐减少;Bax蛋白的表达随着药物浓度增加逐渐增加。结论:IA能够抑制HepG2细胞的增殖,并使细胞大量累积于G1期,进入S期的细胞减少,通过影响凋亡蛋白表达诱导细胞凋亡。     

猕猴桃藤山柳茎叶中的三萜化合物

目的:进一步阐明我国特有属药用植物猕猴桃藤山柳的化学成分.方法:采用硅胶和MCI柱色谱及制备液相色谱等分离方法对该植物茎叶的化学成分进行分离纯化,经质谱和核磁共振波谱技术进行结构鉴定.结果:从猕猴桃藤山柳茎叶的甲醇提取物中分离纯化出16个化合物,其结构分别鉴定为桦木酸(1)、乌苏酸(2)、齐墩果酸(3)、科罗索酸(4)、3β-反式对香豆酰氧基-2α,23-二羟基-12-烯-28-乌苏酸(5)、3β-反式对香豆酰氧基-2α,23-二羟基-12,20(30)-二烯-28-乌苏酸(6)、2α,3α,23-三羟基乌苏-12,20(30)-二烯-28-酸(7)、2α,3α,23-三羟基乌苏-12-烯-28-酸(8)、积雪草酸(9)、2α,3α,24-三羟基乌苏-12-烯-28-酸(10)、2α,3β,23-三羟基乌苏-12,20(30)-二烯-28-酸(11)、2α,3β,19α,23-四羟基乌苏-12-烯-28-酸(12)、2α,3α,19α,24-四羟基乌苏-12-烯-28-酸(13)、2α,3β,23,24-四羟基乌苏-12-烯-28-酸(14)、2α,3α,19α,23,24-五羟基乌苏-12-烯-28-酸(15)和胡萝卜苷(16).结论:这些化合物主要为乌苏烷型三萜成分,其中化合物3～6,11,12,14和15为首次从该单种属植物中分离得到.     

云南鼠尾草茎叶中化学成分及其抗血管生成活性研究

目的:研究云南鼠尾草茎叶的化学成分,寻找抗血管生成活性成分,综合开发药用植物资源.方法:利用溶剂超声提取,硅胶柱色谱、凝胶柱色谱、MCI柱色谱等分离手段进行分离纯化,根据化合物理化性质和波谱数据对其进行结构鉴定,通过鸡胚尿囊膜模型(CAM)进行活性筛选.结果:从提取物中共分离得到7个化合物,分别被鉴定为(+)桉油烯醇(1)、5,7,4'-三羟基二氢黄酮(2)、β-香树素(3)、3β-羟-12-乌苏烯(4)、马斯里酸(5)、熊果酸(6)、3-氧-12-烯-28-乌苏酸(7).抗血管生成实验表明化合物5,6在鸡胚尿囊膜模型中表现出较好抗血管生成作用.结论:化合物1,2,5,6首次从该植物中分离得到,并首次发现化合物5(齐墩果烷型),6(乌苏烷型)在0.8 nmoL/egg的剂量下就具有抑制血管生成的活性,且呈剂量依赖性.