The Study Of Synthesizing Structure Lipid Catalyzed By Immobilized Lipase

The structure lipid is a new kind lipid that MCT and LCT created by transesterification. The object of synthesis structure lipid optimized fatty substrate mixture, using the function and speciality of each fatty acid, and making the synthetical structure lipid have better excellence. The experiment first filtered all kinds of carriers, selected alkalescence anion exchange resin D301-G as the carrier immobilizing lipase, and optimized the immobilizing condition of D301-G: absorption 8h in 13 ℃ shake bed. the absorption time is 8h, enzyme activity is 127IU/g, the concentration of Glutaraldehyde solution is 1%, the time of crosslinking is 10min. The enzyme activity of immobilized lipase is 28.0 IU/g(average).Transesterification of lecithin with olive oil was catalyzed by lipolase ( NOVO company ), and the temperature , time, enzyme activity, ratio of the substrate concentration , water content was studied, the optimized conditions that transesterification of lecithin with oil catalyzed by lipolase was obtained: in 100mL flask, 20mL hexane, 45℃, 12h, 3.0mg lipolase(4.1IU/mL), ratio of lecithin and olive oil =1:4 (m/v), 20 μ L water. The content of C_18:1 and C_18:2 of the structure lecithin was 59.92% by GC analysis.The transesterification of lecithin with olive oil catalyzed by the immobilized lipase D301-G was studied. The optimized conditions of transesterification of D301-G was as follows: in 100mL flask, 20mL hexane, 45℃, 24h, 7 5g immobilized lipase D301-G(10.5IU/mL), ratio of lecithin and olive oil =1:3 (m/v), 20 μ L water. The content of C_18:1 and C_18:2 of structure lecithin is 79.87% by GC analysis.Then transesterification of lecithin with fish oil catalyzed by lipolase was studied. The optimize conditions: in 100mL flask. 20mL hexane, 45 ℃, 12h, 5.0mg lipolase(6.9IU/niL), ratio of lecithin and fish oil =1:4 (m/v), 20 μ L water. The content of EPA/DHA of structure lecithin was 6.83%, the content of EPA and DHA was respectively 1.40% and 5.43%. The immobilized lipase D301-G is of no effect to the transesterification of lecithin with fish oil.The enzymatic synthesis of lecithin containing EPA and DHA can improve its oxidation stability. The structure lecithin can be incepted by cell completely, and is decomposed into DHA, EPA, phosphatidylaholine in cell showing enhance effect. It can be used in food , cosmetic, medicine.