以Fe(III) 改性胶原纤维为载体固定过氧化氢酶

Immobilization of catalase on Fe (III) modified collagen fiber

摘要:

将胶原纤维用三价铁改性后作为载体，通过戊二醛的交联作用将过氧化氢酶固定在该载体上。制备的固定化过氧化氢酶蛋白固载量为16.7 mg/g，酶活收率为35％。研究了固定化酶与自由酶的最适pH、最适温度、热稳定性、贮存稳定性及操作稳定性。结果表明：过氧化氢酶经此法固定化后，最适pH及最适温度与自由酶相同，分别为pH 7.0和25 ℃；但固定化酶的热稳定性显著提高，在75 ℃保存5 h后，仍能保留30％的活力，而自由酶则完全失活；固定化酶在室温下保存12 d后，酶活力仍保持在88％以上，而自由酶在此条件下则完全失

Abstract:

Fe (III) modified collagen fibers were used to immobilize catalase through the cross-linking of glutaraldehyde. The loading amount of catalase on the supporting matrix was 16.7 mg/g, and 35% enzymatic activity was remained. A series of experiments were conducted on free and immobilized catalase in order to investigate their optimal pH and temperature, and the thermal, storage and operation stability. Results suggest that the free and immobilized catalase prefer similar pH and temperature condition, which were pH 7.0 and 25 °C. It should be noted that the thermal stability of catalase was considerably improved after immobilization owing to the fact that the enzyme kept 30% of relative activity after incubation at 75 °C for 5 h. On the contrary, the free catalase was completely inactive. As for the storage stability, the immobilized catalase kept 88% of relative activity after stored at room temperature for 12 days while the free one was completely inactive under the same conditions. Moreover, the immobilized catalase preserved 57% of relative activity after being reused 26 times, exhibiting excellent operation stability. Consequently, this investigation suggests that collagen fiber can be used as excellent supporting matrix for the immobilization of catalase, and it is potential to be used for the immobilization of similar enzymes.