目的 基于活性导向分离蓝萼香茶菜Rabdosia japonica中具有吲哚胺2，3-双加氧酶（IDO）抑制作用的成分。方法 蓝萼香茶菜地上部分经水提醇沉后得粗多糖XPS，其经活性跟踪测定、DEAE Sepharose Fast Flow阴离子交换树脂分离和Superdex-75系列凝胶纯化后得XPS10-1，并对XPS10-1进行HPGPC法分析、单糖组成测定、氨基酸组成分析和IDO抑制活性检测。结果 从蓝萼香茶菜中得到一种具有IDO抑制作用的均一糖蛋白成分XPS10-1，相对分子质量为8 852，糖基部分主要由鼠李糖基和葡萄糖基组成，物质的量比为10.0：2.2，蛋白部分主要由谷氨酸、丝氨酸和甘氨酸组成，物质的量比为37.3：16.9：45.8，XPS10-1表现出较强的IDO抑制活性，半数抑制浓度（IC₅₀）值为（46.6±3.4）μg/mL，XPS10-1对人宫颈癌HeLa细胞中IDO酶也有抑制作用，IC₅₀值为（139.0±8.7）μg/mL。结论 从蓝萼香茶菜中成功分离到具有IDO抑制作用的糖蛋白，为蓝萼香茶菜的化学物质基础提供依据。

Objective To isolate indoleamine 2,3-dioxygenase (IDO) inhibitory constituents from Rabdosia japonica based on bioactivity tracking separation. Methods The overground part of R. japonica was extracted with boiling water and precipitated by ethanol, the precipitation was collected and lyophilized to obtain XPS, then successively separated by DEAE Sepharose Fast Flow anion-exchange and Superdex-75 gel permeation chromatographic steps to give XPS10-1. A combination of HPGPC, monosaccharide and amino acid composition analysis and IDO inhibitory studies was performed to investigate the structure and bioactivity of XPS10-1. Results A IDO inhibitory glycoprotein, XPS10-1, was obtained from R. japonica based on activity tracking, its average molecular weight was estimated to 8 852, monosaccharide composition analysis showed the glycosyl part of XPS10-1 was mainly composed of rhamnose and glucose with the ratio of 10.0:2.2, and the protein part was mainly composed of glutamic acid, serine and glycine with mass ratio of 37.3:16.9:45.8. XPS10-1 showed potent IDO inhibitory effect with IC₅₀ of (46.6±3.4) μg/mL, and IC₅₀ of IDO inhibitory effect of XPS10-1 on HeLa cells was (139.0±8.7) μg/mL. Conclusion In this study, a glycoprotein with IDO inhibitory effect was isolated from R. japonica, which could lay the foundation for the substance basis study of R. japonica.

R284.1

上海市科委科研计划项目（15DZ1900100）；上海市科委科研计划项目（15DZ1900104）；上海市自然科学基金（20ZR1458100）；上海市青年科技启明星计划资助（19QB1406500）