| As new generational surfactants, APG is the main kind of surfactants. For its'superior performance ,now it has been widely used in the food industry, agriculture, biological and chemical, petroleum industry, fiber and textile industry, paper industry, pharmaceutical manufacturing, the management of red tide, demulsifier agent, thickener, dispersing, dust-proof agent, materials science and other fields. However, at the present time, it is studied more deeply in the chemical method which production's purity is very poor, so it can't be used in food, medicine fields and so on.The synthesize of APG by glycosidase has many advantage, its'production's purity is very good, no by-products, in particular the reaction condition is very mildly and the energy consumption is very low, so it has been concerned more and more widely.the research onβ-glycosidase can be traced back to 1837, the years of research by scholars at home and abroad made its'purification technology quite sophisticated and the large-scale production has taken shape. Therefore, the use of enzymatic production of APG has a very good condition but it also has disadvantage. Direct contacting with enzymes and organic reagent can make the enzyme inactivate easily, and can't reused. If the reaction needs more time, there will be more enzyme needed to compensate for enzyme inactivation.So, the research on APG synthesis which is catalyzed by immobile enzyme is essential, and it has a far-reaching significance. The main aim of this paper is to research on APG synthesis catalyzed by immobile enzyme, and Focusing on the fixed enzyme selection, the optimize of the fixed enzyme and the optimize of APG's synthesis. The conclusions as following:First of all, at the part of selecting fixed method experimentation, we not only compared the glucose conversion rate of reaction system catalyzed by different microcapsules- fixed glycosidase but also compare the different microcapsules- fixed glycosidases'reusability.The conclusions we got as following: First, compared with ACA microcapsule fixed method, covalent cross-linking fixed method and embedded fixed method.The enzyme fixed by ACA microcapsul- e has higher catalytic ability and better reusability.Second, at four centigrade, ACA microcapsule fixed enzyme has a long shelf -life in the refrigerator. After sixteen days, the ability of catalyze reaction did not reduce. Third, after fixed, some physical properties of enzyme has changed.The second part, at this part, we optimize the technics of ACA microcapsule fixed method through single factor experimentation and twice orthogonal universal revolving combination design test.The conclusions we got as following:First, with the increaseing of the concentration of acetic acid, the solubility of chitosan is increasing. the viscosity of the material solution, and microcapsule particle diameter is increasing.And the glucose conversion rate of the reaction system increases first and then decreased.At 0.4%, the lucose conversion rate of the reaction system reach the maximum. Second, when the concentration of acetic acid is 0.4%, the solubility of chitosan is 0.6-1.2g/100ml. With the increaseing of chitosan dosage, glucose conversion rate of the reaction system increases first and then decreased.and reach the maximum.at 0.2g/50ml. Third, when the concentration of sodium alginate is 0.48-4.8g/100ml,the microcapsule is well. With the increaseing of Sodium alginate, glucose conversion rate of the reaction system decreased.and reach the Maximum.at 0.6g/50ml.Fourth, with the increaseing of the concentration of glutaraldehyde, glucose conversion rate of the reaction system increases first and then decreased.and reach the maximum.at 0.6g/50ml.Fifths, with the increaseing of reaction time, glucose conversion rate of the reaction system increases quickly.but after six hour, the change did not significantly. Sixth, reaction system of glucose conversion rate was less affected by the concentration of CaCl2, when at concentrations of 1.5% is the better.Seventh, with the increaseing of the time in CaCl2, glucose conversion rate of the reaction system increases first and then decreased.and reach the maximum.at 30min. Eighth, the four influential factors (the quality of chitosan(X1), the reaction time in CaCl2(X2), the concentration of Glutaraldehyde (X3), and the quality of alginate (X4)) as study object, through twice orthogonal universal revolving combination design test, get the regression equation:Ninth, through analysis of the regression equation: the interaction between the factors was not significant, so need not specific analysis.The last part, at this part, we optimize the technics of the synthesize of APG through single factor experimentation and dual quadratic rotary regression orthogonal design test.The conclusions we got as following:Frist, with the increaseing of the reaction temperature, glucose conversion rate of the reaction system increases first and then decreased.and reach the maximum at 45 centigrade.At 50 centigrade, part of fixed enzyme has been inactivation and it will be worse when the temperature higher.Second, with the increaseing of the water in the reaction system, glucose conversion rate of the reaction system gradually decreased and the time to balance point become longer. Third, the glucose conversion rate of reaction system was less affected by the pH, with the increaseing of the pH, glucose conversion rate of the reaction system gradually decreased.Forth,with the increaseing of the dodecanol in the react system, glucose conversion rate of the reaction system gradually increased, but when volume of dodecanol added bigger than 6ml, the chang of glucose conversion rate of the reaction system is little. Fifths, with the increaseing of fixed enzyme, glucose conversion rate of the reaction system gradually increased, but when fixed enzyme added more than 5g, the chang of glucose conversion rate of the reaction system is little.Sixth, with the increaseing of the quality of glucose, glucose conversion rate of the reaction system increases first and then decreased.and reach the maximum.at 0.5-1g. Seventh,with the increaseing of the melting point of alcohol, glucose conversion rate of the reaction system decreased, considerate with product and price, the best selection is dodecanol. Eighth, the four influential factors (reaction temperature(X1), the volume of alcohol added(X2), the volume of water added (X3), the reaction time(X4)) as study object, through dual quadratic rotary regression orthogonal design test, get the regression equation:Ninth, through analysis of the regression equation we know that all factors are in the interaction, and the interaction is positive. Factors temperature and the volume of alcohol, temperature and the volume of water added, temperature and reaction time, the volume of alcohol added and volume of water added interaction is bigger than the other major interaction.In this study, through a large number of experimental studies, we determine the best technics of APG's synthesis catalyzed by immobileβ-glucosidase in micro-capsule. As general economic be considerated, the ACA microcapsules fixed method is the best way to fixedβ-glucosidase. The best fixed parameter is: Chitosan 0.4g/100ml, Sodium alginate 1.2g/100ml, Acetate 0.4ml/100ml, the concentration of CaCl2 is 1.5% and the time in it is30min, the concentration of glutaraldehyde is 0.25% and the time in it is 6h. The optimum condition of synthesis is: fixed enzyme 5g, glucose 1g, dodecanol 6ml, reaction temperature 45℃, reaction time 4d.The innovation points of the thesis:First,β-glucosidase fixed by ACA microcapsule method, and goet the best process parameters by single-factor and twice orthogonal universal revolving combination design test.Second, useing of single factor experimentation and dual quadratic rotary regression orthogonal design test in immobilized enzyme-catalyzed synthesis of APG, and got the best process parameters.
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