柱前衍生-气相色谱法测定枸杞粗多糖中4种糖醛酸

Determination of four uronic acids in crude lycium barbarum polysaccharides by pre-column derivatization-gas chromatography

以枸杞为原料,通过水提醇沉方式得到枸杞粗多糖,建立柱前衍生-气相色谱法测定枸杞粗多糖中4种糖醛酸(D-葡萄糖醛酸、L-艾杜糖醛酸、D-甘露糖醛酸、D-半乳糖醛酸)的含量。采用三氟乙酸作为水解剂,于120℃水解90 min,采用HP-1701毛细管色谱柱分离,分流比为15∶1,氢火焰离子化检测器(FID)检测,外标法定量。结果表明,4种糖醛酸的质量浓度在0~100μg/mL范围内与色谱峰面积线性关系良好,相关系数均大于0.999。样品加标回收率为90.55%~96.40%,测定结果的相对标准偏差均小于10%(n=6)。该方法满足枸杞粗多糖中糖醛酸含量的检测。

Lycium barbarum crude polysaccharide was obtained by water extraction and alcohol precipitation with Lycium barbarum as raw material.A pre-column derivatization-gas chromatography method was established to determine the contents of four uronic acids(D-glucuronic acid,L-iduronic acid,D-mannuronic acid,D-galacturonic acid)in Lycium barbarum crude polysaccharide.The sample was hydrolyzed by trifluoroacetic acid at 120°C for 90 min,separated by HP-1701 capillary column with a split ratio of 15∶1,detected by hydrogen flame ionization detector(FID),and quantified by external standard method.The results showed that the mass concentration of the four uronic acids had a good linear relationship with the chromatographic peak area in the range of 0-100μg/mL,and the correlation coefficients were all greater than 0.999.The recoveries of spiked samples were 90.55%-96.40%,and the relative standard deviations of determination results were less than 10%(n=6).This method meets the detection of uronic acid content in lycium barbarum crude polysaccharide.