Abstract: The trypsin that the molecular weight is 23.8 kD is the hydrolytic enzyme which comes from animal. It has the extensive application in medicine, food, industry and so on. This article has studied the trypsin immobilization method as well as the use of trypsin immobilization for casein hydrolysis. Based on determination of trypsin enzyme activity, a macropore weak anion exchange resin Duolite A7 was screened for trypsin immobilization, the optimized resin addition amount is 0.5g/10mg protein, and enzyme activity still reached more than 30% after five-time recycling of the immobilized enzyme. Conditions on pH, temperature, entrapment amount on effect of trypsin activity were investigated by Ca-alginate gel beads, the sodium alginate concentration is 15 g/L, CaCl2 20 g/L, the trypsin entrapment amount is 60mg/10mL sodium alginate; the optimal temperature and pH are 60℃ and 7.4 respectively.
Keywords: Trypsin; Immobilizition; Ca-alginate; Duolite A7 resin