Polysaccharides from Rhizoma Panacis Majoris and its anti-oxidant activity

Response surface method (RSM) was employed to optimize the extraction conditions of polysaccharides from Rhizoma Panacis Majoris (the rhizomes of Panax japonicus C. A. Mey. var. major (Burk.) C. Y. Wu et K. M. Feng) (RPMP), a well-known Chinese traditional medicine. In order to obtain the optimal processing parameters, a three-variable Box-Behnken designs (BBD) were applied for experimental designs. RSM analysis indicated the good correspondence between experimental and predicted values, the optimal conditions for the yield of polysaccharides were as follows: the ultrasound time is 31.15 min, extraction temperature is 92.50 °C, and the ratio of water to raw material is 40 mL/g. The maximum value (13.87 ± 0.16%) of the yield of polysaccharides was obtained under these optimal conditions. The molecular weight (MW) was determined to be 1.48 × 105(± 0.39%) Da by HPSEC-MALLS-RID chromatography system. FT-IR spectra demonstrated obvious characteristic peaks of polysaccharides. The antioxidant activities of RPMP were investigated including scavenging activity of hydrogen radicals, ABTS radicals, and free radicals of superoxide anion in vitro, and the results exhibited that RPMP had a good potential for antioxidant.