Isolation, purification and structure characteristics of polysaccharide from Portulaca oleracea L.

Objective To study the technology of separating and purificating of polysaccharides from Portulaca oleracea L.. Method The polysaccharide was obtained from Portulaca oleracea L. by hot water extraction followed by precipitation with ethanol and purified with DEAE cellulose column chromatography. The molecular weight and the composition of the polysaccharides were determined by high-performance gel-permeation chromatography (HPGPC) and the gas chromatography, respectively. Results Five kinds of pure polysaccharides (POPS ₀ , POPS ₁ , POPS ₂ , POPS ₃ and POPS ₄ ) were obtained. The purify of POPS ₀ , POPS ₁ , POPS ₂ , POPS ₃ and POPS ₄ were 84.31%, 92.14%, 90.45%, 88.47% and 82.16%. The molecular weight of these polysaccharides was 1.801×10 ⁴ Da, 5.583×10 ⁴ Da, 2.721×10 ⁵ Da, 6.006×10 ⁵ Da and 9.443×10 ⁵ Da. POPS ₀ was composed of glucose and galactose; POPS ₁ was composed of rhamnose, glucose and galactose; POPS ₂ was composed of arabinose, xylose, mannitose, and galactose; POPS ₃ was composed of xylose, glucose and galactose; POPS ₄ was composed of arabinose, glucose and galactose. Conclusion The experiments provided basis for further research of polysaccharide from Portulaca oleracea L..