Font Size: a A A

Studies On1,3-diacylglycerol Production By Lipase And The Immoblization Of Lipase

Posted on:2014-09-26Degree:MasterType:Thesis
Country:ChinaCandidate:P DongFull Text:PDF
GTID:2180330467485206Subject:Nutrition and Food Hygiene
Abstract/Summary:PDF Full Text Request
Diacylglycerol (is called DG for short) is a glycerol ester that have a molecule of glycerol of two molecules of free fatty acid formation, it can be divided into two isomers, because free fatty acid binds glycerol carbon skeleton at differert place,that is1,3-diacylglycerol (1,3-DG) and1,2-diacylglycerol (1,2-DG), natural plant oil contains trace amounts of diglyceride, chich also is intermediate in body fat metabolism. Diacylglycerol is not accumulate in the body, can reduce the blood lipid level effectively, thus to improve health level about lipid, such as reducing blood fat, lowering blood pressure, improve arteriosclerosis and help to control body weight.Firstly, based on the existing diacylglycerol analysis method, optimized a new method which has the advantages of simple operation, short time, low cost and results as accurate. The chromatography conditions were as follows:HYPERSIL Silica Dim.(mm)250×4.6,n-hexane:isopropanol:glacial acetic acid=96:4:0.1(V/V) mobile phase and the flow was0.75mL/min, the injection volume was3//L, the pump pressure was1.9MPa; used evaporative light scattering detector, atomized by nitrogen, temperature in drift tube was60℃, pressure was360kPa.Novozymes immobilized lipase Lipozyme TL IM as a reference, the four kinds of lipase(A, B, C, D) as a selection object, preparing enzyme activity and diglyceride productivity that catalyzed by the lipase, selected two comprehensive evaluation better lipase, using the response surface design method to optimize production condition of high purity1,3-diacylglycerol from soybean oil. The results showed that:the maximum yield prediction1,3-DG was57.27%catalyzed by Lipozyme TL IM from soybean oil,immobilized lipase Lipozyme TL IM of soybean oil catalyzed by diacylglycerol preparation; compared the four lipases, C and D was selected, and using the response surface design method to optimize production condition of1,3-diacylglycerol from soybean oil.It was showed that lipase D had a higher yield than the lipase C,maximum yield of1,3-diacylglycerol,the productivity was51.33%of D lipase, and the reaction conditions were easy to realize.Lipase D was used to be immobilized by gel, several conditions that effect on lipase entrapping were studied, such as the alginate ratio of lipase and sodium alginate, the amount of sodium alginate, immobilization time, the amount of Ca2+; the thermal stability,and the stability in solution which had metal ion of the immobilized lipase was studied,it showed that immobilized lipase were stable than befer.Oxidation stability and the effects of different antioxidants on the oxidative stability of diacylglycerol has been studied. The results showed that:the strongest antioxidant activity was TBHQ that is a synthetic antioxidant, followed by the natural antioxidant tea polyphenols and lycopene, antioxidant activity of the two were stronger than tocopherol of three kinds of natural antioxidants. And the effect had reached the ideal value when additive amount of antioxidant was300ppm.
Keywords/Search Tags:Diacylglycerol, triacylglycerol, lipase, immobilized, hydrolyze, oxidationstability
PDF Full Text Request
Related items