Extraction, derivatization, and antioxidant activity of Morinda citrifolia polysaccharide

The polysaccharide from Morinda citrifolia fermentation liquor was extracted by the hot water method. The acetylated polysaccharide, phosphorylated polysaccharide, carboxymethylated polysaccharide, and sulfated polysaccharide were identified by IR and NMR spectra. The results showed that Morinda citrifolia polysaccharide and its derivatives showed the good antioxidant activity, and them up to V_c level. These results provide a good basis for studying the antioxidant activity and structural-activity relationship of Morinda citrifolia polysaccharide and its derivatives.