Study On The Preparing Technique Of Phosphatides Which Abundantly Contain N-3 Polyunsaturated Fattyacids

Phospholipids (PL) are major constituents of cell membranes and play crucial roles in the biochemistry and phsiology of the cell. They have been widely used in food, pharmaceutical, and cosmetic products as highly proficient emulsifiers. Soy phopholipids are receiving renewed interest for modifications by chemical and biochemical reactions. Modified phospholipids could have better surface-active properties and nutritional quality than the original compounds. Enzymatic catalysis offers the potential of a nondestuctive, reaction-mild route for PL modification. At present, phospholipase A2 is used industrially to produce lysophospholipids, which are more hydrophlic and have better emulsfying properties at low pH and at high salt concentrations than the original material. However the enzyme are not readly or economical available in the amounts requied for the condut of large-scale reactions. Modified PL fatty acid composition and distribution may improve the immune function. Structured Phospholipids containing ARA,EPA or DHA have beneficial effects on immune function, nitrogen balance, and improved lipid clearance from bloodstream.Lecitase Utra-catalyzed hydrolysis in a solvent-hexane system was optimized. using response surface methodology (RSM), a three-level four-factor fractional factorial design with star points was adopted. The four major factors chosen were lipase dosage (Ld, wt.% based on PL), PL/solution( wt/vol), reaction time (Ti, h), water content (W, wt.% based on PL). Based on the fitted model, the optimal reaction conditions for the hydrolysis of phospholipids by Lecitase Utra-catalyzed were found to be Ti, 17h; Ld, 5%; Te, 50℃; PL/solution,18%, and W, 105%. At these experimental conditions, the acid value of PL was 78.8 mg /g. KOH and then Novozyme 435-catalyzed esterification in a solvent-hexane system was optimized. using response surface methodology (RSM), a three-level four-factor fractional factorial design with star points was adopted. Based on the fitted model, the optimal reaction conditions for the production of structured phospholipids by Lecitase Novozyme 435-catalyzed acidolysis between soybean deoiled lysophospholipids and fish FA were found to be Ti, 70h; Ld,14%,( wt.%, based on substrates); Te, 50℃; M,3/1 (mol/mol, acid/phospholipids); PL/solution, 11%, and W, 2%( wt.% ,based on lip-ase). At these experimental conditions, 14.41% incorporation of AA,EPA and DHA can be obtained.Novozyme 435-catalyzed acidolysis in a solvent-hexane system was optimized. using response surface methodology (RSM), a three-level four-factor fractional factorial design with star points was adopted. Based on the fitted model, the optimal reaction conditions for the production of structured phospholipids by Novozyme 435-catalyzed acidolysis between soybean deoiled phospholipids and fish FA were found to be Ti, 69h; Ld,14%,( wt.%, based on substrates); Te, 50℃; M,6/1 (mol/mol, acid/phospholipids); PL/solution, 20%, and W, 2%( wt.% ,based on lipase). At these experimental conditions, 9.87% incorporation of AA,EPA and DHA can be obtained.