Enzymatic Preparation Of L-α-glycerophosphocholine In An Aqueous Phase And Its Microscopic Properties

Phosphatidylcholine(PC)and its hydrolyzate L-a-phosphatidylcholine(GPC)are widely used in the field of medicine and health care products.The enzyme-catalyzed reaction around the PC also plays an important role in medicines,foods,cosmetics and other industries.In this paper,the changes of the surface chemical properties before and after the enzymatic hydrolysis of lecithin suspension were studied,and the catalytic process for the preparation of phosphatidylcholine was studied,which provided a new catalytic system for the biotransformation of phosphatidylcholine.It was indicated that when the pH of the buffer increased,the particle size becomes larger,the conductivity of the system increased,the absolute value of Zeta potential decreased,the viscosity decreased.When phospholipase catalyzed the lecithin suspension,the zeta potential of the lecithin suspension fluctuated,after a slight decrease in pH,the equilibrium was finally maintained at 4.70,and the conductivity was slightly increased and eventually balanced at 9.50mS/cm,fluid viscosity decreased due to the decreased solid content,and eventually balanced.Based on the studieds of the surface chemical properties of lecithin suspensions,the aqueous phase reaction system that was used as enzymatic preparation of GPC was established,of which catalytic conditions were studied.The results showed that the initial substrate concentration is 20.0%,the reaction temperature was 55 ℃,the initial pH was 5.0,the enzyme dosage was 87.03U/g,when the reaction was carried out for 90 minutes,the final concentration of the reaction was reduced from 20.0%to 6.5%.At this time,the final concentration of the suspension was increased from 6.5%to 13.0%after a supplementation of additional substrate,and the reaction was continued for 6 hours,the conversion of PC would be about 90%.Feeding the substrate concentration is beneficial to the enzymatic reaction.The supplementation of additional substrate is beneficial to the enzymatic reaction.In this paper,the separation and purification of the products after the enzymatic reaction was studied.the purification process of the product firstly separated the fat-soluble impurities by extraction,when extracted,the amount of dichloromethane is 0.4 times the volume of the reaction solution and the amount of methanol is 0.5 times.The product was alkalized and then decolorized,and mobile phase was methanol and the stationary phase was neutral alumina,when decolorized.Thereafter,part of the sodium acetate was removed by solvent desalination,and the solvent used was anhydrous ethanol at a temperature of 55 ℃.Finally,the product needs to be purified by silica gel column chromatography with a mobile phase of 9:1 mixture of methanol and 30%ammonia water.In this paper,the pH,viscosity and substrate contents of the aqueous system were determined by the key characterization of the aqueous phase catalytic system.The GPC product was prepared in this system,and the results provide a theoretical reference for the green phosphatidylcholine biotransformation technology.