中文摘要：

挥发性单萜（C10）与倍半萜（C15）,常具有宜人的花果香气。茶鲜叶中此类物质的种类及其糖苷化合物的含量和水解对成品茶的香气香型有重要影响。就可能影响茶树挥发性萜类物质及其糖苷化合物合成途径中的限速反应和相关的酶进行综述,认为1-脱氧-D-木酮糖-5-磷酸还原异构酶（DXR）和羟甲基戊二酰辅酶A还原酶（HMGR）是影响萜类代谢前体异戊烯基焦磷酸（IPP）及二甲烯丙基焦磷酸（DMAPP）的限速酶。单萜和倍半萜合成酶是挥发性萜类化合物生物合成途径中的关键酶。此外,糖基转移酶可能与茶鲜叶中糖苷态萜类香气化合物的合成和积累有关。糖苷水解酶则催化茶鲜叶中糖苷态香气物质的水解,导致香气物质的释放。调节相关基因的表达,将有可能控制萜类代谢流向挥发性萜类合成分支。本文还讨论了影响茶叶香气品质的其他因素,如茶树品种、栽培环境,以及加工方法等。

英文摘要：

Tea aromatic quality is largely dependent on the spectrum and abundance of volatile terpenoids and their glycosides produced and accumulated in tea leaves. Very often, the compounds of monoterpenes （C10） and sesquinterpene （C15） possess pleasant floral scent, contributing significantly to tea aromatic quality. However, studying on the biosynthesis pathway of these volatile terpenoids and their glycosides in tea plant is just at beginning. In this review, speed-limiting biosynthetic steps and related enzymes in plant volatile terpenoid biosynthesis pathways are summarized. The genes encoding 1-deoxy-D-xylulose-5-phosphate reductoisomerase （DXR） and 3-hydroxyl-3-methylglutaryl-CoA reductase （HMGR） as well as terpenoid synthases are proposed as key enzymes for volatile terpenoid biosynthesis. Uridine diphosphate-glycosyltransferase may affect biosynthesis and accumulation of glycosides of volatile terpenoids in tea plant while glycosidase play a key role in the glycoside hydrolysis and release of glycosidically bound terpenoid volatiles during tea leaf processing. Manipulation of these genes may control the flux of the terpenoid metabolism towards the volatile terpenoid biosynthesis. The ~actors influencing tea aromatic quality such as tea cultivars, growing management, processing ways are also discussed.