Abstract:

Acetylated polysaccharides from Cyclocarya paliurus were prepared by using acetic anhydride method. An
orthogonal array design was used to investigate the effects of ratio between acetic anhydride and polysaccharids, reaction
temperature and reaction time on the efficiency of acetylated modification as evaluated by degree of substitution (DS). The
antioxidant activity of acetylated polysaccharide (DS = 0.681) was investigated by DPPH radical scavenging capacity. The
optimal conditions for acetylated modification were determined as 1:60, 2 h and 40 ℃ for ratio between acetic anhydride
and polysaccharids, reaction time and reaction temperature, respectively. The results indicated that acetylated modification
could enhance the antioxidant activity of Cyclocarya paliurus polysaccharides significantly. In conclusion, acetylation could
be considered as an efficient method for the modification of Cyclocarya paliurus polysaccharides which provides a new
direction for the development and utilization of Cyclocarya paliurus.

Key words: Cyclocarya paliurus (Batal.) Iljinskaja, polysaccharides, acetylation, antioxidation