MWCO = 3500da. . 3 analysis method

MWCO = 3500da. . 3 analysis method (1) determination of total sugar content phenol concentrated sulfuric acid method [65] was used to determine the total sugar content of Betula platyphylla. The determination principle: under the action of concentrated sulfuric acid, the dehydrated furfural or hydroxymethylfurfural can condense with phenol to produce a colored substance. After reaction, the solution becomes an orange red compound, the color depth is proportional to the sugar content, and there is a maximum absorption peak at 490nm wave length, and the absorption value has a dose effect relationship with the polysaccharide content. This method is simple, fast, sensitive and durable. Preparation of 100ug / ml glucose standard solution: accurately weigh 50mg of anhydrous glucose dried to constant weight and add water to a 500ml volumetric flask for constant volume. 60% phenol stock solution: accurately weigh 60g phenol and dissolve it in 40ml distilled water, store it in dark at 4 ℃ for standby.