Extraction optimized by using response surface methodology, purification and preliminary characterization of polysaccharides from Hyriopsis cumingii

Extraction, purification and preliminary characterization of polysaccharides from Hyriopsis cumingii (HCPS) were carried out. Firstly, the extracting parameters for HCPS extraction were optimized by using three-factor-three-level Box–Behnken design and response surface methodology based on the single-factor experiments. As results, the optimum conditions were extracting temperature 80 °C, extracting time 4.5 h and the ratio of extraction solvent (water) to raw material (v/w) 8. Under these conditions, the experimental yield of crude HCPS was 3.66%. Secondly, the crude HCPS was purified by DEAE-Cellulose 52 chromatography and Sephadex G-100 chromatography to afford 3 fractions, HCPS-1, HCPS-2 and HCPS-3. The recovery rates based on crude HCPS used were 26.91%, 30.18% and 3.93% for HCPS-1, HCPS-2 and HCPS-3 respectively. Based on the characterization results of HCPS by Fourier transform-infrared spectroscopy, high performance liquid chromatography and gas chromatography, we found that HCPS-3 was quite different from HCPS-1 or HCPS-2.