The Study Of Natural And Synthetical Phosphatidylethanolamine's Separation By The Silica Gel Column Chromatography

The high-purity phosphatidylethanolamine (PE) surpasses phosphatidylcholine (PC) regarding improving human body memory and enhancing cerebrum function. Simultaneously, the high-purity PE has the function of maintaining and improving cognition. Its application value is extremely important. The content of PE in natural phospholipids is low, so its separation and purification are difficult. In the application of lecithin, as a result of instauration of the fat chain, its chemical stability, dispersivity, emulsibility and so on are not good. But the application of synthetical lecithin having the saturated fat chain is broader and safer, particularly in medicine and food industry.At present, the most high-purity phospholipids products used in domestic mostly depends on import from overseas. The demand of high-purity lecithin reaches several tons per year. But the traditional research focuses on PC, neglecting importance of PE. Therefore, the main purpose of this experiment is to obtain the high-purity PE method, simultaneously carry on the modification to the molecular structure of PE to obtain stable structure, which can meet the needs of PE in medicine, food industries and so on.This article takes natural phospholipids PC-60 as raw material, using the silica gel column chromatography and isocratic elution, to inspect elution situation of phospholipids in the silica gel column. The best technological condition is that the eluent is chloroform/methyl alcohol (2/3, v/v), under the room temperature, loading amount is 0.025g phospholipids raw material /g silica gel, and the speed of flow is about 3ml/min. Under above conditions, the purity and recovery percent of PE can reach 96.2% and 89.6%. By enzymatic conversion method, the content of PE in natural phospholipids can be raised to 80%. In the separation process of synthesis PE obtained by enzymatic conversion method, the best technological conditions is that the eluent is chloroform/methyl alcohol (1/2, v/v), under the room temperature, loading amount is 0.03g phospholipids raw material /g silica gel, the speed of flow is about 45 drop /min. Under above conditions, the purity of PE can reach 98.3%, the recovery percent is 90.4%, which can satisfy the request of high-purity phospholipids preparation. Meanwhile other low poisonous eluents have been selected, also obtaining the good result.This experiment also carries on replacement reaction between the stearic acid and the unsaturated chain of natural phospholipids, obtaining Distearoyl-Phosphatidylethanolamine (DSPE) whose purity is higher than 95% by column separation. The infrared analysis indicated that DSPE hasn't absorption peak of unsaturated bond, which has enriched the PE research, and provided reliable data support for the industrialization of PE production in the future.