The Immobilization Of Lipases And Its Enzymatic Properties

Lipase (Lipase, EC3.1.1.3) is a kind of enzyme whose catalytic ability more diverse andis widely used in many fields. but it is difficult to separate from products, can not be reused.lipase is extensively concerned because of its stability and repeated use through the method ofimmobilization The most problem of immobilized enzyme is the large dosage of carrier, thelife span of the immobilized enzyme is short. Due to this, in this paper we based on themodified diatomite and self-assemble chitosan microspheres as the carrier, to immobilizelipase then find the best immobilized conditions and study enzyme properties of immobilizedlipase, and compares the ester exchange efficiency of both the immobilized enzymes in theactual applicationThe main work is as follows:1. The roasting method is adopted to modify the diatomite, first under the environment ofhigh temperature, diatomite surface has a great influence on the diatomite adsorbent throughtransformation of hydroxyl, compareing the adsorption amounts of lipase we can get the bestroasting temperature is450℃, then with the method of alkali leaching to purify thediatomite. Using scanning electron microscope (SEM) of self-assemble secondary modifieddiatomite to characterize the appearance shape, particle diameter, the experimental resultsshow that the secondary modified diatomite with fully transparent aperture and neatlyarranged, and it is a good carrier of adsorption method immobilized enzyme.Using the method of reversed-phase suspension with glutaraldehyde as crosslinkingagent to prepare self-assemble chitosan microspheres.The prepared chitosan microspheresmeets the conditions of the immobilized enzyme crosslinking method with uniform size wellballinged and good skeleton.2. Select the best condition of lipase immobilization used single factor experimentmethod with the modified diatomite and chitosan microspheres as the carrier.3. Compare the free lipase enzymology property with that of the two preparedimmobilized enzyme After immobilization heat resistance, pH stability, thermal stability lipase are highly improved, and the immobilized enzyme is of great significance in theindustrial production.4. With self-assemble immobilized enzyme catalizing catering waste oil to synthsisesters, The effect of modified diatomite immobilized lipase is better than that of chitosanmicrospheres either in life span or in efficiency...