The preparation mainly composed of extraction, pre-purification and dehydration is essential for the research and development of natural polysaccharides. The methods or conditions used in the three procedures had significant effects on the composition, structure and function of the polysaccharides obtained. Temperature, pH, enzyme, ultrasound and microwave were the important factors associated with their physicochemical changes. Molecular degradation and intermolecular interaction were two of the main mechanisms responsible for the changes. The degradations of polysaccharides responding to hyd...
