【作者】 刘星；

【导师】 李海舟；

【作者基本信息】 昆明理工大学 ， 植物学， 2013， 硕士

【摘要】 本论文主要分为四个部分,第一部分对植物防卫素(Phytoalexins)的研究状况进行了综述；第二部分对龙血竭研究概况进行了综述,并对国产龙血竭的化学成分进行了系统研究,对从龙血竭中分离得到的不同类型酚性成分的紫外光谱特征进行了分析；第三部分对分离得到的酚性成分进行抗菌活性实验,并探讨了龙血竭酚性植物防卫素的形成机制；第四章对本论文的工作进行讨论及总结。血竭(Dragon’s Blood)为世界各地广为使用的民间药物,有悠久的应用历史,被称为“活血之圣药”。上世纪70年代著名植物学家蔡希陶教授在云南南部发现剑叶龙血树(Dracaena cochinchinensis S. C. Chen)树脂可以作为正品血竭的国产代替品,现已成为市场上的主流品种。为了进一步系统研究其化学成分,探讨其形成机理,以现代植物化学研究方法,利用各种分离纯化手段,对国产龙血竭氯仿提取物进行了系统地化学研究,共分离50个化合物,鉴定了其中的43个化合物,包括3个新化合物,23个为首次从国产龙血竭中分离得到。化合物类型涉及7个黄烷、9个二氢查耳酮(1个新化合物)、7个小分子酚性成分、6个木脂素、2个二苯乙烯、4个甾体、4个多酚二聚体成分(2个为新化合物)以及4个其它类型成分。通过对比分析不同类型酚性成分的紫外光谱图发现：龙血竭中不同类型酚性成分的紫外光谱特征有很大差异,以配有二极管阵列检测器(DAD)的高效液相色谱(HPLC),可在线定性分析预判其可能的成分类型,指导酚性成分的分离纯化和鉴别。抗菌实验表明,部分酚性成分具有抗菌活性,其中简单的小分子酚性成分的抗菌活性最强。龙血竭酚性成分是剑叶龙血树树干受到损伤后在微生物的侵染或者(／和)自然氧化作用下逐渐形成。从龙血竭成分形成的规律看：龙血树树干原化学成分以甾体皂苷为主,酚性成分含量很少；而受病原微生物侵袭形成红色树脂后,则主要成分转化为酚性成分,其中的酚性成分具有抗菌活性,很明显这些具有抗菌活性的酚性化合物就是剑叶龙血树所产生的植物防卫素。更多还原

【Abstract】 This paper comprises four chapters altogether. The first chapter of the chemical constituents of phytoalexins from the plants was reviewed. The second chapter reviewed the chemical constituents of the red resin of Dracaena cochinchinensis and discussed the studies on the chemical composition from the red resin of D. cochinchinensis, then study phenolic constituents from Chinese Dragon’s Blood and its ultraviolet spectrum characteristic.The third chapter illustrated the antibacterial activities of phenolic constituents against Staphylococcus aureus and Escherichia coli,and then study the formation mechanism of phenolic phytoalexins from the resin of D. cochinchinensis. And in the last chapter, conclusion of this dissertation is made.Dragon’s blood is a deep red resin, which has been used as a precious traditional medicine as well as a colorant in works of art by many cultures since ancient times. In the course of searching for more new natural compounds and investigated the formation mechanism of the red resin of D. cochinchinensis, we further systematically investigated the red resin of D. cochinchinensis, which led to the isolation and elucidation of fouty-three compounds.Different phenolic constituents from Chinese Dragon’s Blood have especially ultraviolet spectrum characteristic by the contrastive analysis of the Ultraviolet Spectrum. The method can be applied to extraction and isolation a type of phenolic constituents from dragon’s blood.Most of the phenolics have antimicrobial activity against S. aureus and E. coli0157:H7.Ethyl-p-hydroxy benzoate was found to be most efficacious against S. aureus and E. coli0157:H7. Phenolic compounds were almost undetectable in the fresh stem xylem of D. cochinchinensis, but were induced and accumulated dramatically in the dragon’s blood resin after wounding and microbial infection. On the basis of the results of phytochemical study and the antibacterial activities against Staphylococcus aureus and Escherichia coli, these compounds would play a vital role in the defense strategy of D. cochinchinensis by wounding. These results imply that phenolic compounds of the dragon’s blood resin are a special group of phytoalexins.更多还原