天花粉免疫活性多糖RTPS-Ⅰ的分离及性质结构研究

Study on Isolation and Structure Characteristics of Immunoactive Polysaccharide RTPS-Ⅰ from Trichosanthis Radix

目的:从天花粉中分离纯化免疫活性多糖RTPS-Ⅰ,并进行性质、组成和初步结构研究。方法:采用水提醇沉方法制备天花粉粗多糖,经过三氯乙酸法除蛋白,DEAE-Cellulose、DEAE-Sepharose FF和Sephadex G-200柱色谱分离纯化,得到均一的免疫活性多糖组分RTPS-Ⅰ。利用化学法、高效凝胶过滤色谱法、气相色谱法,并结合红外光谱和核磁共振,对RTPS-Ⅰ进行性质结构分析。结果:RTPS-Ⅰ为白色絮状固体,易溶于水,由碳、氢、氧3种元素组成,比旋光度[α]25_D(H_2O)为+164.44,相对分子质量为17 555,糖基组成为葡萄糖,不含糖醛酸,糖环为吡喃环,各单糖间以α-型糖苷键相连接。结论:首次从天花粉中分离得到均一的免疫活性多糖RTPS-Ⅰ。

Objective： To separate and purify the immunoactive polysaccharide RTPS- I from Trichosanthis Radix and study the physicoehemical properties and preliminary structure. Methods： The crude polysaecharides were extracted by water, and then precipita- ted by ethanol. After the deproteinization with trichloroaeetic acid, the polysaecharide RTPS- I was separated and purified by using DE- AE-Cellulose, DEAE-Sepharose FF and Sephadex G-200 column chromatography. The analysis of properties and structure was performed by using GC, HPGPC, IR and NMR. Results ： RTPS- 1 was a white floceulent solid after vacuum freeze-drying, and soluble in water. It contained three elements （carbon, hydrogen and oxygen） with the specific rotation [ a ]25（H2O） of ＋ 164.44 and the relative molecular mass of 17 555. The glycosyl in RTPS- I was composed of glucose without uronic acid. The sugar ring was pyranoid ring, and each monosaccharide was linked by a-glycosidic bond. Conclusion： A homogeneous immunoaetive polysaeeharide RTPS- I from Trichosanthis Radix is isolated for the first time.