大狼毒三萜类化学成分的研究

自大戟科(Euphorbiaceae)植物大狼毒(Euphorbia nematocypha Hand—Mazz)根的乙醇提取物的苯溶解部分,经20%AgNO₃硅胶层析,分离得到七个三萜类成分。根据光谱(IR,EIMS,¹H—NMR和¹³C—NMR)和化学方法,确定其中一个化合物为新化合物,命名为大狼毒醇(nematocyphol,Ⅳa),其它化合物为已知物:印度荆芥醇乙酸酯(nepehinol acetate Ⅰ),日尔曼醇乙酸酯(germanicol acetate Ⅱ),大戟醇(euphol,Ⅲ),蒲公英醇(taraxasterol,Ⅴa),24-亚甲基环阿尔廷醇(24-methylenecycloartanol,Ⅴa)和印度荆芥醇(nepehinol,Ⅶa)。这些化合物均为首次从大狼毒中得到。     

Antioxidative action of methanolic extract and buthanolic fraction of Vochysia tucanorum Mart. in the gastroprotection

Aim of the study

Vochysia tucanorum is an important medicinal plant used in the Cerrado of Brazil against gastric disorders and this study reveals the pharmacological action of this traditional medicine use.

Materials and methods

The methanolic extract (E-MeOH) and buthanolic fraction (Fr-Bu) obtained from V. tucanorum were challenged by different necrotizing agents in rodents. NO-synthase inhibitor (L-NAME) and SH blocker (NEM) were used to evaluate the participation of cytoprotective factors in E-MeOH and Fr-Bu gastroprotection. Antiulcerogenic action of V. tucanorum was evaluated in rats and mice at doses 250, 500 or 1000 mg/kg (E-MeOH) and 37.5, 75 or 150 mg/kg (Fr-Bu).

Results

Both E-MeOH and Fr-Bu present elevated gastroprotective action in all in vivo experimental models, without signs of acute toxicity. The mechanisms involved in the gastroprotective action of E-MeOH and Fr-Bu are related to the antioxidant activity and protection to gastric mucosa NO levels. Phytochemical investigations of Fr-Bu identified different pentacyclic triterpenoids such as betulinic acid, erythrodiol, epi-betulinic acid and mixtures of ursolic acid and oleanolic acid derivatives as the major constituents. The presence of such triterpenoids in Fr-Bu is probably related to the potent gastroprotective action of this medicinal plant species.

Conclusion

Effectiveness in gastroprotection and the absence of acute toxicity indicate this species as a promising herbal drug that is in accordance with ethnopharmacological use against gastric disorders.     

5种中草药水提取液对灵芝三萜含量的影响

目的研究5种中草药水提取液对灵芝液体培养的菌丝体生物量和三萜含量的影响。方法在基本培养基中分别添加了终浓度为5%的中草药水提取液,液体培养4 d后,测定各灵芝菌丝的生物量和三萜含量。结果与结论中草药水提取液对菌丝体生物量均有促进作用,其中银杏促进作用最明显,增幅达27.7%,而生地最弱,增幅为4.6%;而生地水提取液对灵芝菌丝体的三萜含量有抑制作用,其余4种有促进作用,其中银杏增幅最高为17.1%。     

Triterpenoids from the stems of Myricaria paniculata

Two new pentacyclic triterpenoids myricarin A and B (1 and 2) have been isolated from the stems of Myricaria paniculata, together with seven known compounds, myriconal, 28-hydroxy-14-taraxeren-3-one, epi-friedelanol, β-sitosterol, 4-methyl stigmast-7-en-3-ol, 12-hentriacontanol and 1-triacontanol. Their structures have been established by chemical and spectroscopic methods. Cytotoxic activities of 1 and 2 have been evaluated against several different cell lines.     

Triterpenoids from<Emphasis Type="Italic">Schisandra henryi</Emphasis> with cytotoxic effect on leukemia and hela cells<Emphasis Type="Italic">in vitro</Emphasis>

Four known lanostane triterpenoids, schiprolactone A (1), schisanlactone B (2), nigranoic acid (3) and schisandronic acid (4) were isolated from the stems of Schisandra henryi for the first time. Their structures were characterized by IR, MS and NMR techniques. Compounds 1, 2 and 4 showed moderate cytotoxic activity against Leukemia cells in vitro. Cytotoxic activity of compounds 1-4 showed IC50 of 0.0097, 0.01, 0.097 and 0.0099 micromol/mL respectively toward Leukemia cells and IC50 of 0.097, 0.1, 0.097 and 0.099 micromol/mL toward Hela cells respectively. It is the first report that these compounds possess cytotoxic activity on Leukemia and Hela cells.     

Antimycobacterial triterpenoids from Lantana hispida (Verbenaceae)

As the Mycobacterium tuberculosis strains resistant to multiple drugs are increasing at an alarming rate, there is an urgent need for alternative anti-tuberculosis drugs. In a bioassay-guided search for antimycobacterial compounds obtained from higher plants, the study of the hexane extract from the aerial parts of Lantana hispida was performed and the biological activity of the plant products were tested against Mycobacterium tuberculosis H37Rv strain by microdilution alamar blue assay. Activity of the primary fractions led to the isolation of three pentacyclic triterpenoids with oleanane nucleous, together with beta-sitosterol. The molecular structures of the compounds were characterized as 3-acetoxy-22-(2'-methyl-2Z-butenyloxy)-12-oleanen-28-oic acid (1), 3-hydroxy-22 beta-(2'-methyl-2Z-butenoyloxy)-12-oleanen-28-oic acid (reduced lantadene A) (2) and oleanolic acid (3). MIC values for compounds 1 and 2 were 50 microg/ml, and for compound 3 the MIC=25 microg/ml.     

头序木叶中三萜化学成分的研究

从头序木（ＡｒａｌｉａｄａｓｙｐｈｙｌａＭｉｑ）叶中分离到６个三萜化合物，用化学方法和波谱（ＵＶ，ＩＲ，ＭＳ，１ＨＮＭＲ，１３ＣＮＭＲ，１３ＣＤＥＰＴ，ＨＭＱＣ，ＨＭＢＣ）分析，确定其中４种化合物的结构，分别为齐墩果酸（Ｉ），１６β羟基１８βＨ齐墩果酸（Ｉ），齐墩果酸２８ＯβＤ吡喃葡萄糖甙（ＩＩ）和１６β羟基１８βＨ齐墩果酸２８ＯβＤ吡喃葡萄糖甙（ＩＶ）。用ＮＯＥＳＹ谱确定化合物Ｉ的立体构型。以上４个化合物均为首次从该植物中分离到，化合物ＩＶ为新化合物。     

地梢瓜化学成分的研究

从萝藦科鹅绒藤属植物地梢瓜(Cynanchum thesioides)的全草中共分离到十四个化合物,本文报道已鉴定的七个化合物。其中两个新化合物分别为1,3-二棕榈酸-2-山梨酸-甘油三酯(4)和地梢瓜甙(7)。五个已知化合物鉴定为β-香树脂醇乙酸酯(1),羽扇豆醇乙酸酯(2),α-香树脂醇正辛烷酸酯(3),柽柳素(5),柽柳素-3-O-β-D-半乳糖甙(6)。     

灵芝三萜类化合物对AD大鼠脑海马神经细胞Aβ1-40的影响

目的 研究灵芝三萜类化合物(GLT)对阿尔茨海默病(AD)大鼠脑海马神经细胞Aβ1-40表达的影响.方法 将自然衰老模型大鼠60只随机均分为六组:模型组,GLT低、中、高剂量组,溶媒对照组(食用油)及阳性对照组(健脑胶囊),5个月龄大鼠10只为正常对照组.连续灌胃给药60 d后,免疫组化法检测海马Aβ1-40表达.结果 模型组海马神经细胞Aβ1-40表达增多,GLT组Aβ1-40表达减少.结论 GLT有防治AD的作用,其作用机制可能与减轻Aβ的神经毒性以及减少脑内Aβ沉积有关.     

合蕊五味子中两个新的三萜内酯及其在生物合成途径中的意义

目的：研究合蕊五味子（Schisdndrapropinqua var.propinqua）地上部分化学成分。方法：利用正反相硅胶、高效液相色谱等现代分离技术进行分离,利用IR,UV,MS和NMR等现代波谱技术手段鉴定了它们的结构。结果：分离得到两个分别具有3,4-seco—cycloartane和3,4：9,10-seco—cycloartane型骨架的新三萜内酯：propiniclactnnesA（1）和B（2）;同时分离得到了一个典型的cycloartane骨架三萜类化合物。结论：这两个新化合物在生源合成途径上具有重要意义,它们可能是连接cycloartane骨架三萜和schisandra降三萜骨架的重要中间体。