三萜皂苷是植物界中具有多种生物活性的一类重要的植物次生代谢产物，是许多药用植物或中药材的重要活性成分之一，阐明三萜皂苷的生物合成途径具有重要的理论意义与广阔的应用前景。近年来，三萜皂苷整个生物合成途径的阐明，尤其是三萜碳环骨架合成及环上复杂官能化等相关酶基因的确定与克隆，仍是众多学者关注与研究的热点。本文对三萜皂苷的生物合成途经和有关“鲨烯及三萜碳环骨架合成和碳环上的复杂官能化”的关键酶进行了综述，为深入阐明三萜皂苷生物合成途径及人工生物合成提供理论基础。

As an important kind of plant secondary metabolites and widely distributed in the plant kingdom, triterpenoid saponins have a variety of biological activities. The constitution and content of triterpenoid saponin are determined by some key enzymes and their expressing level in triterpenoid saponins biosynthesis pathway. So, it is very important to illuminate the molecular mechanism of triterpenoid saponins biosynthetic pathway. In recent years, illumination of the entire biosynthetic pathway especially the confirmation and cloning of the key enzymes, such as squalene synthase, squalene epoxidase, cytochrome P450 monooxygenase and UDP-glycosyltransferase, had become one of the hot spots by many scholars. In this paper, the entire biosynthetic pathway and some kinds of key enzymes involved in the synthesis of carbon skeleton, and its oxidation, and glycation were reviewed for further demonstrating the biosynthetic pathway of triterpenoid saponins and providing a theoretical basis for artificial biosynthesis.

国家自然科学基金委青年科学基金项目（31100244）：基于代谢组学及高通量测序技术筛选远志差异活性成分与皂苷合成关键酶基因，负责人：张福生；山西省科技厅科学技术发展计划（20140313010-1）：山西大宗道地药材优良种质筛选关键技术研究示范，负责人：张福生；科学技术部国家科技支撑计划（2011BAI07B05）：华北区沙棘、远志、葛根、板蓝根、栝楼、北柴胡等规划范化种植基地及其SOP优化升级研究，负责人：谢晓亮。