Optimization of polysaccharide extraction process from grifola frondosa and its antioxidant and anti-tumor research

In order to get high yield polysaccharide from grifola frondosa, single factor experiment and an orthogonal experiment were applied to optimize the best extraction conditions. Extraction time, extraction temperature, ratio of raw material to water and auxiliary factors (microwave assisted, ultrasound assisted) were the main factors to influence the yield and purity of the extracted crude polysaccharide. The optimum conditions were as follows: extraction time 3.5h, extraction temperature 75 degrees C, ratio of raw material to water 1:15 and ultrasound assisted. Under the optimal conditions, the experimental extraction yield of polysaccharides from grifola frondosa was 7.36%+/- 0.21% (n=3). In this experiment, a novel comparison was made to explore the effect of microwave assisted extraction and ultrasonic assisted extraction of polysaccharide from hot water. Furthermore, the antioxidant activity of polysaccharides from grifola frondosa suggested that the polysaccharide had great antioxidant effect, especially scavenging activity for reducing power and DPPH radical. And polysaccharide from grifola frondosa has anti-tumor activity, which can inhibit the proliferation of HepG2 cells. This study has shown that the polysaccharides from grifola frondosa can be explored as a novel natural antioxidant and anti-tumor drug.