Immobilization of Wheat Esterase and Effect onProperties of the Enzyme

摘要

Wheat esterase has been immobilized by ion exchanging method. The effects of typeand form of ion exchanging resins, esterase activity of enzyme solution, immobilizing time,buffer concentration and pH on the immobilization have been investigated. Using theimmobilized esterase activity or the activity recovery rate of immobilization as criterion,conditions for immobilizing were selected as: D261 anion exchanging resin of form OH- ascarrier of immobilized esterase, 0.025 M sodium phosphate pH 6.8 buffer, and immobilizing timeof 1.7hr. Simultaneously, the properties of immobilized and free wheat esterase have beencompared. The results showed that the optimum pH for immobilized esterase was 0.8 unithigher than that for free esterase which was located at pH 4.8 and however, the optimumtemperature for the immobilized esterase has not shifted significantly while the peaky form oftemperature-activity curve became more precipitous than that of free esterase. In regard toinhibiting effect, immobilized esterase showed more sensitive to the inhibition oforganophosphate pesticide (dichlorvos) than free esterase.