Study On Catalytic Characteristic And Adsorption Capacity Of Double Substrates Recorded Lipase

The article is studied in lipase and use two new technique-bioimprinting technique and molecular imprinting technique to prepare the double substrates recorded lipase. Lipase conformation can be induced by substrate to be an activated one in preparation process. Then the activated conformation was recorded using high cross linking degree polymer. And the final enzyme conformation is rigid. The double substrates recorded lipase's catalytic characteristic in water and organic solvent, and its adsorption capacity were investigated.The dissertation emphasizes on exploring the process of double substrates recorded lipase preparation. Lipase, lauric acid and n-butyl alcohol were added into a copolymer system, which contained four different kinds of function monomer and trimethylolpropane trimethacrylate. The polymerization was obtained by ultraviolet irradiation and lauric acid, n-butyl alcohol were extracted by petroleum ether. The function monomer and crosslinked agent were mixed by the scale of 2:1(mass scale) and irradiation time was 45s.The dissertation studied the catalytic characterization of double substrates recorded lipases in water and organic solvent. The four double substrates recorded lipases presents some catalytic activity and stability. The best catalytic activity was attained by double substrates recorded lipase Da in water (3.71U/g). And the results shown that the monomer containing methyl could easily increase steric hindrance of recorded lipase Da, which will increase the mass-transfer barriers lead to the decrease of the catalytic activity(Ba>Aa, Da>Ca). The four double substrates recorded lipases present their the best catalytic activity at pH=7.5 and at 50℃～60℃. Moreover, they were able to retain higher catalytic activity under the circumstance of strong acid(pH=2.40), strong alkaline(pH=12.00) and high temperature, respectively. And after immersing the double substrates recorded lipases into precipitation denaturants for 20 days, the four double substrates recorded lipases were able to retain at least 50% of their initial activities. It illuminates the four double substrates recorded lipases can be also keep higher catalytic activity in precipitation denaturants. The activity in organic solvent (heptane) was measured by esterification of lauric acid and n-butyl alcohol. When rising the temperature, the activity and yield are also rising. After catalyzing 24h, Da's best catalytic activity (20.92 U/g) was attained at 60℃ in organic solvent.The dissertation is also studied the adsorptive ability of the double substrates recorded lipase Da. It has found the Da has some adsorptive ability to lauric acid and n-butyl alcohol. The influence factors including temperature, solvent, Da's catalytic activity is studied. When rising the temperature, the adsorption is also rising. Its equilibrium adsorption amount was 37.55(mg·g^-1) at 50℃.The solvent impact Da's adsorptive ability through influence the interaction between the polymer and ligand. The non- activity Da's adsorptive ability drops significantly. Moreover, the cavities created in the double substrates recorded lipase by lauric acid and n-butyl alcohol during impringting are not unique for these ligand. A dozen of lauric acid and n-butyl alcohol analogs can bind to the double substrates recorded lipase.