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Non-ionic surfactant, a sucrose fatty acid ester is an important physiological function has been widely used in food, cosmetics and pharmaceutical fields. Susceptible to microbial degradation of sugar esters, and harmless to the environment, in recent years, the production of sugar esters increasing its broad prospects for development indicates that the huge commercial value. Currently, most of the commercially available fatty acid sugar esters are obtained by reaction of saturated fatty acids with sugar, studies and reports of the unsaturated fatty acid sugar esters are relatively small, however, in view of the unsaturated fatty acid has numerous biological and physiological characteristics. In recent years, the research center of gravity of the glycolipid surfactant has gradually turned to sugar esters of unsaturated fatty acids. In this paper, unsaturated fatty acids and trehalose as raw material, the use of lipase-catalyzed synthesis of trehalose esters of unsaturated fatty acids in the organic phase, and study its properties. The first step, the in ScS five lipase-catalyzed indicators based on filter out suitable unsaturated fatty acids trehalose preferred lipase for ester synthesis. Used by lipase-catalyzed performance in several organic solvents comparison, the Novozyme435 catalytic efficiency is much higher than Lipozyme RM IM, Lipozyme TL IM, Porcine pancreatic, these four Carcia papaya lipase, therefore, Novozyme435 is locked for the experimental enzymes. In the study on the basis of the performance of lipase-catalyzed surement solvent for an effective synthesis of trehalose is an unsaturated fatty acid ester, The effects of n-hexane, tert-amyl alcohol, acetone, t-butanol and DMSO five organic solvent selective synthesis esterification rate, identified by t-butoxide for the synthesis of trehalose preferred reaction medium of the unsaturated fatty acid monoester, acetone preferred reaction system for the synthesis of unsaturated fatty acid diester of trehalose and optimized in an acetone solvent the process conditions of erucic acid diester of trehalose. The best conditions: molecular sieve concentration of 60 g / L, lipase concentration of 20 g / L, acid and alcohol than 4:1 (mol / mol), trehalose concentration of 25 mmol / L, under the 55 ° C water bath oscillating reaction 42 h, and in This optimum conditions derived trehalose erucic acid diester in a yield of 51%. In addition, the course of the experiment were used the IR, HPLC, MS, and NMR characterization and identification of the structure of the synthesized product. The unsaturated acid carbon chain length of the esterification reaction. Trehalose as a substrate, through its oleic acid, linoleic acid, conjugated linoleic acid, peanut oil, acid and erucic acid synthesis reaction study, indicating the greater, the greater the steric hindrance of the substrate molecules, the synthesis of the more difficulty large. Trehalose, the surface properties of an unsaturated fatty acid sugar esters, and the melting point, water-soluble, HLB value, foaming properties and emulsifying properties. Found that trehalose is an unsaturated fatty acid diester are poor foamability, after adding a small amount of monoester compound remains unchanged, but the diester emulsion is very good, especially linoleic acid diester, showing strong emulsification stability.
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