Study On Ultrasonic Assisted Preparation Of Carboxymethyl Pachyman And The Method For Determination Of Carboxymethl Pachyman

In this study,Poria cocos was taken as the subject investigated.In order to improve the solubility and degree of substitution of modified Poria powder,carboxymethyl pachyman was prepared with ultrasonic wave.The alkali soluble pachyman in Poria cocos were extracted by ultrasonic wave,and then the one with carboxymethyl modification was separated by anion exchange chromatography column.We chosen the carboxymethyl pachyman that has been purified as a control to test the accuracy on the content of polysaccharide in carboxymethyl pachyman determined by phenol-sulfuric acid method.The main results were as follows:1.The technical conditions,used for the preparation of carboxymethyl pachyman was optimized through orthogonal design,but with the consideration of cost and effect,we gained that the optimum on the ratio of solid to liquid,ultrasonic time and temperature were 1:4,30 min and 60℃ separately.In this condition,the substitution degree of carboxymethyl pachyman increased by 42%,reaching 0.78 finally.2.Alkali soluble pachyman was extracted with ultrasonic and conventional stirring separately,their yields were 83.72% and 86.01%,and the extraction time was3 min and 8 h,it showed that ultrasonic assisted extraction has higher extraction efficiency.The results of UV-Vis spectrum,FT-IR spectrum and gas chromatography indicated that ultrasonic effect had no destructive on the structure of pachyman.The analysis of antioxidant activity revealed that ultrasonic assisted extraction of pachyman(concentration was 0.2 mg/mL-1.0 mg/mL)had better antioxidant activity than the one that extracted with traditional stirring.3.Different substitution degree of carboxymethyl pachyman was prepared to study on antioxidant activity of carboxymethyl pachyman in the concentration range of 0.1mg/mL-2.5mg/mL.It showed that their biological activity has a dose-effect relationship on the concentration and was not associated with degree of substitution.4.Carboxymethyl pachyman with different substitution of reference was used as referece to establish the relation curve between the degree and the polysaccharide content,it proved that the degree of substitution has an impact on the accuracy of phenol sulfuric acid method in determining polysaccharides content of carboxymethyl pachyman...