摘要
由于中药多糖结构复杂、相对分子质量大,难以表征,该研究以中药北沙参40%乙醇沉淀多糖(Glehniae Radix polysaccharides,RGP)为研究对象,应用"自下而上"法完成对RGP的结构表征。该文最初采用部分酸水解方法水解RGP,分别考察了酸浓度、水解时间和温度对其水解效率的影响。在最佳条件(1.5 mol·L^(-1)TFA,4 h,80℃)下,RGP被水解为特征性寡糖片段。之后,采用HILIC-LC-MS对RGP部分酸水解产物进行分离和结构表征。同时结合几种标准二糖的MS和MS/MS分析,建立依靠质谱分析确定多糖糖苷键类型的方法。结果确定了4种糖苷键连接类型在MS/MS中的断裂规律,并发现RGP为含有1,4-糖苷键的线性葡聚糖,水解得到聚合度4~11的葡寡糖。
Water-soluble polysaccharides from traditional Chinese medicine have properties of complex structure and high molecular, resulting in hardly complete their structural characterization.However, a ＂bottom-up＂ approach could solve this problem.Glehniae Radix extract was extracted with hot water and then precipitated by 40% ethanol to obtain Glehniae Radix polysaccharides （RGP）. Subsequently, a partial acid hydrolysis method was carried out and the effects of acid concentration, time and temperature on hydrolysis were investigated. Under the optimum hydrolysis condition （1.5 mol·L^-1 trifluoroacetic acid, 4 h, and 80℃）, RGP were hydrolyzed to characteristic oligosaccharide fragments. Futher, a hydrophilic liquid chromatography-mass spectrometry method was used for the separation and structural characterization of the polysaccharide hydrolysates. According to MS and MS/MS analysis of several standard disaccharides, a method for determining the type of polysaccharide glycosidic linkage by mass spectrometry was established. The results showed that the polysaccharide hydrolysates were linear glucan containing 1, 4-glycosidic bonds. And gluco-oligosaccharides with the degrees of polymerization （DP） of 4-11 were obtained after partial acid hydrolysis.
出处
《中国中药杂志》
CAS
CSCD
北大核心
2017年第24期4814-4818,共5页
China Journal of Chinese Materia Medica
基金
国家"重大新药创制"科技重大专项(2014ZX09509001-001)
关键词
部分酸水解
质谱
亲水作用色谱
北沙参多糖
partial acid hydrolysis
mass spectrometry
hydrophilic liquid chromatography
Glehniae Radix polysaccharides
