显齿蛇葡萄中二氢杨梅素代谢积累机制研究

The content of total flavonoids and dihydromyricetin in dried leaves of Ampelopsis grossedentata is so high, accounting for 45.52% and 39.50%, respectively,which is honored as "King of Flavonoids-rich plant". Ampelopsis grossedentata synthetizing flavone aglycones as its main secondary metabolites, which differs from other flavonoids-rich plants yielding flavonoid glycosides. At present, the mechanism of synthetizing flavone aglycones of Ampelopsis grossedentata is still unclear. Therefore, it is of great theoretic and practical significance to study the accumulation of secondary metabolites of the plant. In order to illuminate the key precursors and competitive substrates involved in the biosynthetic pathway of dihydromyricetin, the content of dihydromyricetin and related compound in Ampelopsis grossedentata will be detected by analytical instruments such as high-performance liquid chromatography. With the aid of SPSS software and correlation analytic methods, the correlation between the content of compounds will be analyzed. The correlation between climatic factors and the content of compounds will be analyzed using Data Processing System (DPS) and grey correlation degree analytic method. In order to clarify the physiological and ecological mechanism of the metabolic accumulation of dihydromyricetin, the dynamic changes of dihydromyricetin and the related compounds from dihydromyricetin-rich and dihydromyricetin-poor plants cultivated in the same habitat will be studied. The results will lay a foundation for further study on the molecular mechanism of the metabolic accumulation of dihydromyricetin, and provide theoretical basis for studies on the metabolism of other flavone-rich plants.

显齿蛇葡萄干叶中黄酮的质量分数达45.52%，仅二氢杨梅素的含量就达39.50%，被誉为"植物黄酮之王"； 不同于其他富含黄酮植物倾向于合成黄酮苷，该植物以苷元为主。然而，目前显齿蛇葡萄合成黄酮苷元的机制尚不明确，因此，开展显齿蛇葡萄次生代谢积累机制研究具有重要的理论和实际意义。本研究采用HPLC等仪器分析手段测定显齿蛇葡萄中二氢杨梅素及其生源相关化合物的含量，并借助SPSS软件的相关性分析法探求化合物含量之间的相关性，明确二氢杨梅素代谢积累的关键前体及竞争性底物；研究极端二氢杨梅素含量植株在同一生境栽培后二氢杨梅素及其生源相关化合物含量的动态变化规律，并借助DPS软件的灰色关联度法分析气候因子与二氢杨梅素之间的相关性，阐明二氢杨梅素代谢积累生理生态机制。以期为进一步研究二氢杨梅素代谢积累的分子机制奠定基础，也为其他富含黄酮苷元植物的代谢研究提供理论依据。

项目以探求显齿蛇葡萄中二氢杨梅素的代谢积累生理生态机制及生物学功能为目的，开展如下研究：1）；采用 HPLC法同时测定12个不同产地同一采收期85份样品及同一产地不同采收期24份样品中二氢杨梅素、杨梅素、杨梅苷及香橙素的含量，明确了二氢杨梅素代谢积累的关联化合物；2）基于二氢杨梅素生源合成途径，研究了显齿蛇葡萄生长发育过程中苯丙氨酸解氨酶（PAL）、査尔酮合成酶（CHI）、环境温度对二氢杨梅素代谢积累的影响，证实了PAL 、CHI活性对二氢杨梅素代谢积累的延迟调控作用；3）收集全国25个产地，411株野生显齿蛇葡萄苗，建立中国最大种质资源圃；4）以极端二氢杨梅素含量（高含量及低含量）显齿蛇葡萄植株嫩叶为原料，开展无参基因转录组学研究，发现了黄酮类3'羟化酶（F3'H）、黄酮类 3',5'-羟化酶（F3',5'H）、无色花色素双加氧酶（LAD）及查尔酮合成酶（CHS）二氢杨梅素代谢积累关键合成酶；5）研究二氢杨梅素、杨梅素及杨梅苷含量不同的显齿蛇葡萄样品提取物的α-葡萄糖苷酶抑制活性，明确了杨梅素及杨梅苷为提取物的活性物质基础；6）研究了二氢杨梅素及纯化过程中主要干扰杂质杨梅素在不同溶剂中的溶解度，优化二氢杨梅素提取工艺——分段结晶法；7）开展了显齿蛇葡萄果实提取物中花色苷、多糖含量与抗氧化活性相关性研究，显齿蛇葡萄叶提取物及主要黄酮的α-葡萄糖苷酶抑制活性研究以及二氢杨梅素对高档植物油（亚麻油、山茶油及紫苏油）的抗氧化作用研究；8）基于藤茶，青钱柳在治疗高血糖、高血脂、高尿酸等慢性疾病方面功能互补，开展了青钱柳体外抗氧化、降糖活性及其物质基础研究，明确青钱柳不同部位提取物具有不同的降糖机理。研究结果为深入研究显齿蛇葡萄中二氢杨梅素代谢分子机制提供理论依据，为进一步研究该药用植物在治疗高血脂、高血压、高尿酸及高血糖的体内药理活性及药代动力学研究提供参考，还为拓宽显齿蛇葡萄资源的应用范围奠定基础。