【作者】 赵平；

【导师】 高文远；

【作者基本信息】 天津大学 ， 化学工程与技术， 2021， 博士

【摘要】 黄精属是一类重要的药用植物类群,中药黄精和玉竹都来自于黄精属植物,此外,民间也有多种黄精属植物作药用。但黄精属变异复杂,亲缘关系有不少争议,导致用药混乱。本文以药用植物亲缘学理论为指导,通过对黄精属植物小分子化学成分和多糖特征的系统比较,探讨了黄精属药用植物的亲缘关系。采用高效液相色谱-蒸发光散射检测器(HPLC-ELSD)技术对60批11种黄精属植物的小分子化学成分进行了系统分析,并用化学计量学方法分析了种之间的亲缘关系。发现玉竹中小分子成分最为丰富,热河黄精的成分接近于玉竹。黄精、多花黄精、滇黄精三种药典收载的黄精基原植物在成分上相对接近,长梗黄精、甜味的轮叶黄精等与药典三种基原的黄精成分相对接近。苦味的轮叶黄精中原薯蓣皂苷等呋甾烷型甾体皂苷类成分含量显著高于其他黄精属植物,是苦味的主要成分来源。利用LC-MS鉴定出78个共有峰和差异峰,包括40个甾体皂苷类、12个生物碱类、11个高异黄酮类、6个氨基酸类等成分,其中有4个潜在新化合物。首次明确了黄精属植物的共有成分是氨基酸类、核苷类、溶血磷脂酰胆碱类等,发现富含高异黄酮类成分是玉竹与其他黄精属植物主要区别之一,3-羟基高异黄酮和A环有甲氧基取代的二氢高异黄酮是玉竹的特有成分。从高异黄酮类成分的种类和分布上看,多花黄精和黄精的亲缘关系接近。从甾体皂苷元的氧化程度来看,黄精的进化程度最高。对多花黄精和玉竹进行了多糖的纯化、结构解析和活性筛选。首次解析出玉竹果聚糖(POP-1)的结构是以β-2,1-D-呋喃果糖糖苷键(Fruf)为主链,β-2,6-D-Fruf为支链组成,内含一分子α-D-吡喃葡萄糖基(Glcp),位于糖链的非还原端。从多花黄精中分离到一种含乙酰基的果聚糖(PCP-1),首次确定乙酰基位于α-D-Glcp的O-3位。从多花黄精中还分离到一种果胶(PCP-S3),由半乳糖醛酸、鼠李糖、阿拉伯糖、半乳糖、甘露糖、葡萄糖组成,半乳糖醛酸上有约30%的甲酯化和约10%的乙酰化。果聚糖对健康人和糖尿病患者的肠道菌群组成均有显著的调节作用,而果胶的肠道菌群调节作用不强,但果胶的免疫调节作用比果聚糖更好。采用HPGPC糖谱、单糖组成分析等方法,首次揭示了药典收载的玉竹和黄精的基原植物在多糖特征上的异同。玉竹多糖基本仅由分子量2800～5400 Da的果聚糖组成;而药典三种基原的黄精多糖除果聚糖外,还含有大量分子量约5.7×10~5～4.4×10~6Da的果胶等高分子量的多糖。此外,对非药典收载的7种黄精属药用植物的多糖特征研究结果显示,热河黄精多糖接近于玉竹多糖,可作为玉竹的潜在替代资源。长梗黄精、甜味的轮叶黄精等多糖特征与药典三种基原的黄精类似,可作为黄精的潜在替代资源。对黄精“九蒸九晒”加工过程中多糖理化特征的变化进行了研究,发现多次蒸晒能引起多糖的降解。蒸晒一次对多糖的影响较小;从第2蒸开始,多糖的含量、分子量分布等急剧变化,果聚糖降解严重;第4次蒸制以后,多糖的含量较稳定,但果胶持续降解。综合以上对黄精属植物多糖和小分子成分的研究结果,发现菊糖新生系列型果聚糖是黄精属植物的标志性成分,支持APG分类系统将黄精属划分到天门冬科。果胶等高分子量的多糖是作黄精药用的植物的特征性成分,高异黄酮类化合物是玉竹的特征性成分。本研究为黄精属植物药用资源的合理利用及活性成分的开发奠定了基础。更多还原

【Abstract】 The genus Polygonatum is an important group of medicinal plants.In traditional Chinese medicine,“Huangjing”and“Yuzhu”are derived from the rhizomes of Polygonatum plants.In addition,there are many Polygonatum plants used for medicine in the folk.However,Polygonatum plants has complex variation and and controversial genetic relationship,which leads to the confusion in the use of medicinal plant resources.Based on the theory of pharmacophylogenetic relationships,this study systematically compared the small molecular chemical components and the characteristics of polysaccharides,then discussed the pharmacophylogenetic relationships of Polygonatum plants.High performance liquid chromatography combined with evaporative light scattering detector(HPLC-ELSD)was used to systematically analyze the small molecule chemical constituents of 60 batches and 11 species of Polygonatum,and the method of chemometrics were used to analyzed the pharmacophylogenetic relationships between the species.It was found that P.odoratum had the most abundant small molecular components,the components of P.macropodium was close to P.odoratum.The components of P.sibiricum,P.cyrtonema and P.kingianum recorded in Pharmacopoeia are relatively close,and the components of P.filipes and sweet P.verticillatum relatively close to those three species.The content of furostane steroidal saponins such as protodioscin in bitter P.verticillatum was significantly higher than that in other Polygonatum plants,which might be the main source of bitter taste.78 common and differential peaks were identified by LC-MS,including 40steroidal saponins,12 alkaloids,11 isoflavones and 6 amino acids,among which 4were potential new compounds.The amino acids,nucleosides,lysophosphatidylcholines were firstly defined as the common components of Polygonatum.P.odoratum was rich in homoisoflavonoids,which was one of the main differences between P.odoratum and other Polygonatum plants.3-hydroxyhomoisoflavonoids and dihydrohomoisoflavones with methoxy substitution in A ring were the characteristic components of P.odoratum.According to the types and distribution of homoisoflavonoids,P.cyrtonema and P.sibiricum were closely related.In terms of the oxidation degree of steroidal saponins,P.sibiricum had the highest evolutionary degree.Purification,structure analysis and activity screening of polysaccharides from P.cyrtonema and P.odoratum were performed.The structure of polysaccharides from P.odoratum(POP-1)was firstly comfirmed and it was contained aβ-2,1-D-fructofuranose(Fruf)backbone andβ-2,6-D-Fruf side chains with an internalα-D-glucopyranose(Glcp)at the non reducing end of the chain.A fructan(PCP-1)containing acetyl group was isolated from P.cyrtonema,and the location of acetyl group were firstly determined to be attached at O-3 ofα-D-Glcp.A pectin(PCP-S3)was also isolated from P.cyrtonema,which was composed of galacturonic acid,rhamnose,arabinose,galactose,mannose and glucose with about 30%methylation and 10%acetylation on galacturonic acid.The fructan had a significant regulatory effect on the composition of intestinal flora in both healthy people and diabetic patients.The intestinal flora regulation effect of pectin was not strong,but the immune regulation effect of pectin is better than that of fructan.By HPGPC saccharide mapping,monosaccharide composition analysis and other analytical method,the characteristics of polysaccharides from“Yuzhu”and“Huangjing”were firstly compared.The polysaccharides from P.odoratum were mainly composed of fructans with molecular weight of 2800-5400 Da;while besides fructans,the polysaccharides from P.sibiricum,P.cyrtonema and P.kingianum contained lots of high molecular weight polysaccharides such as pectin with molecular weight of 5.7×10~5～4.4×10~6Da.In addition,the characteristics of polysaccharides from 7 unofficial species of Polygonatum were studied.The results showed that the characteristics of polysaccharides from P.macropodium were similar to that from P.odoratum,indicating P.macropodium could be used as a potential alternative resource of“Yuzhu”.The characteristics of polysaccharides from P.filipes and sweet taste P.verticillatum were similar to those from the P.sibiricum,P.cyrtonema and P.kingianum,suggesting they could be used as potential alternative resources of“Huangjing”.The changes of physicochemical characteristics of polysaccharides from P.cyrtonema during“Nine steaming and Nine drying”processing were studied.The results showed that the first cylcle of steaming had little influence on polysaccharides;from the second cycles of processing,the content and molecular weight distribution of polysaccharides changed dramatically,and fructan degraded seriously;after the fourth cycles of processing,the contents of polysaccharide were stable,but the pectin continued to degrade.Based on the above results on polysaccharides and small molecular components of Polygonatum,it was found that the inulin neoserie type of fructans were suggested to be the landmark components of Polygonatum,which supports APG classification system to classify Polygonatum into Asparagaceae.High molecular weight polysaccharides such as pectin were the characteristic components of“Huangjing”,and homoisoflavonoids were the characteristic components of“Yuzhu”.This study laid a foundation for rational utilization of medicinal resources and the development of active components of the genus Polygonatum.更多还原