Analysis of polysaccharides characteristic, monosaccharide composition and xylitol content of Lycium barbarum

Abstract

ObjectiveTo establish a method to jointly analyze the polysaccharides characteristics， monosaccharide composition and xylitol content of Lycium barbarum.MethodsLycium barbarum polysaccharides were extracted from dried Lycium barbarum fruits by water extraction and alcohol precipitation， and then the extraction rate was calculated. The gel perme-ation chromatography-refractive index-multi-angle laser light scattering method was developed to determine the molecular weight and molecular weight distribution of Lycium barbarum polysaccharides. The extracted Lycium barbarum polysaccharide was hydrolyzed into monosaccharide by trifluoroacetic acid， and a high-performance anion-exchange chromatography-integrating pulse amperometric detection was used to survey and evaluate nine kind of monosaccharides such as arabinose， rhamnose， galactose， glucose， mannose， fructose， xylose， fucose， ribose and one type of xylitol.ResultsThis method was used to detect 10 batches of Lycium barbarum from Ningxia region. It was found that the yield of Lycium barbarum polysaccharide was between 1.86% and 3.21%. The average molecular weight of 10 batches of Lycium barbarum polysaccharides was between 9.12×105～3.65×106 Da. It was found that the order of monosaccharide and xylitol content from high to low was arabinose， glucose， rhamnose， galactose， mannose， fructose， xylitol and fucose in 10 batches of Lycium barbarum detected by ion chromatography.ConclusionThis method to determine average molecular weight， monosaccharide composition and content is more comprehensive， objective and accurate than the detection method in the current quality standard. This study may provide technical reference for establishing the quality control method of Lycium barbarum polysaccharide.

Keywords

• lycium barbarum polysaccharides
• monosaccharides
• molecular
• ion chromatography