莲子心多糖的提取、分离和抗氧化活性研究

Extraction,isolation and antioxidant activity of the polysaccharides from embryo of the seeds of Nelumbo nucifera Gaertn.

干燥的莲子心经机械粉碎、乙醇脱脂、沸水提取、乙醇沉淀及中性酶和Sevag法除蛋白得其粗多糖,经DE-AE-Cellulose-32阴离子交换和SephacrylTMS-200凝胶过滤层析得组份ELPS-Ⅰ和混合物Ⅱ,Ⅱ再经过DEAE-Cel-lulose-32柱层析得组份ELPS-Ⅱ.GC-MS法测定粗多糖、ELPS-Ⅰ和ELPS-Ⅱ的中性糖组成.凝胶过滤色谱(GPC)法测得ELPS-Ⅰ和ELPS-Ⅱ的重均分子量分别为4.97×104Da和2.96×106Da.β-胡萝卜素漂白实验结果显示:莲子心粗多糖具有显著的抗氧化活性(维生素C作为阳性对照).

After grinding and removing lipids from the embryo of the seeds of Nelurnbo nucifera GAERTN. , the polysaccharides were extracted with boiling water and precipitated by 95% ethanol. The precipitates were deproteined by neutroenzyme and Sevag method to afford crude polysaccharides, which were purified by ion-exchange and gel-filtration chromatography on DEAE-Cellulose-32 and SephacrylTM S-200 columns to afford fraction ELPS-Ⅰ and complex Ⅱ. Ⅱ was further subjected to DEAE-Cellulose-32 to afford ELPS- Ⅱ. The neutral sugar compositions of crude polysaccharides, ELPS-I and ELPS-Ⅱwere detected by GC-MS. The weight-average molecular weights of ELPS- Ⅰ and ELPS-Ⅱwere estimated to be 4.97 × 10^4 Da and 2.96 × 10^6 Da by the GPC technique, respectirely. The antioxidant activity of crude polysaccharides was also studied by β-carotene bleaching assay, which showed that crude polysaccharides have distinct antioxidant capacity compared with vitamine C as the positive control.