Study on the Analytical Method for Water-soluble Crude Polysaccharides in Culinary-Medicinal Mushrooms

Size exclusion high performance liquid chromatography (SE-HPLC) was used to analyze water extracts of edible medicinal mushrooms in this research. Fingerprint profiling of polysaccharides in edible medicinal mushrooms was utilized as the primary identification tool for qualitative analysis. Furthermore, this study successfully improves or corrects the overestimation problem in quantifying functional polysaccharide contents in phenol-sulfuric acid method. The comparison of 3 different pre-treatment methods including SE-HPLC fractionation, ultra-filtration (UF) fractionation and alcohol precipitation shows that SE-HPLC fractionation method not only can recover the loss of polysaccharides in UF or alcohol precipitation methods, but also is able to fully retain water-soluble crude polysaccharides with molecular weight > 10 kD, which are commonly regarded as functional components in medicinal mushrooms. Therefore, the combination of SE-HPLC fractionation and phenol-sulfuric acid quantification method is more accurate and suitable for determination of water-soluble crude polysaccharide in edible medicinal mushrooms.