Ultrasonic-assisted extraction, chemical characterization of polysaccharides from Yunzhi mushroom and its effect on osteoblast cells

The objective of the current study was to determine the optimum ultrasonic-assisted extraction conditions for polysaccharides from Yunzhi mushroom. The optimum conditions were evaluated with fractional factorial design and optimized using response surface methodology. The ultrasonic power and the ratio of material to solvent were the most significant parameters on polysaccharides extraction. The extraction conditions were further investigated with Box–Behnken design. The fitted second-order model revealed that the optimal conditions consisted of ultrasonic power 30 W, 1:40 the ratio of raw material to solvent and extraction time 8 h. Under the optimized condition, the maximum productivity of Yunzhi polysaccharides predicted is 5.95%. The extraction productivity and purity of Yunzhi polysaccharides under the optimized extraction conditions were great higher than that of the non-optimized condition. In this study, Yunzhi polysaccharides could enhance alkaline phosphatase (ALP) activity in osteoblast cell. The present study still demonstrates that Yunzhi polysaccharides affects osteoblast cell growth in a dose-dependent manner by stimulating ALP activity.