【作者】 黄文灿； 王伟； 薛长湖； 毛相朝；

【Author】 Huang Wencan;Wang Wei;Xue Changhu;Mao Xiangzhao;College of Food Science and Engineering,Ocean University of China;

【机构】 中国海洋大学食品科学与工程学院；

【摘要】 在该研究中,开发了一种新型生物相容性磁性甲壳素纳米纤维复合物作为酶的固定化载体,并且使用胰凝乳蛋白酶作为模型酶展示了酶固定能力。通过2,2,6,6-四甲基哌啶-1-氧基介导的氧化反应制备了甲壳素纳米纤维,然后用磁性纳米颗粒进一步修饰。戊二醛用于交联胰凝乳蛋白酶分子并将它们固定到磁性甲壳素纳米纤维复合物上。通过透射电子显微镜和傅里叶变换红外光谱表征甲壳素纳米纤维。结果表明,甲壳素纳米纤维形成良好,固定在磁性甲壳素纳米纤维复合物上的胰凝乳蛋白酶分子具有优异的性能。在60℃下将复合物加热3小时后,非交联和交联的固定化胰凝乳蛋白酶分别保留了初始活性的51.6%和70.7%,而游离胰凝乳蛋白酶仅保留了初始活性的29.6%。此外,非交联和交联的固定化胰凝乳蛋白酶在20天后分别保留了初始活性的85.7%和84.9%,而游离胰凝乳蛋白酶仅保留了初始活性的18.8%。当磁性甲壳素纳米纤维复合物用于固定胰凝乳蛋白酶分子时,酶负载能力在交联时增强至6.3倍。而且,固定的胰凝乳蛋白酶可以通过磁力容易地从反应系统中分离和再循环。更多还原

【Abstract】 In this study,a novel biocompatible magnetic chitin nanofiber composite(MCNC) was developed as a support for enzyme immobilization,and the enzyme-immobilizing ability was elucidated using chymotrypsin(CT) as a model enzyme.Chitin nanofibers(CNFs) were prepared via 2,2,6,6-tetramethylpiperidine-1-oxyl(TEMPO)-mediated oxidation of chitin and then further modified with magnetic nanoparticles.Glutaraldehyde was used to crosslink the additional CT molecules and aggregate them onto the MCNCs.The CNFs were characterized by transmission electron microscopy,and Fourier transform infrared spectroscopy.The results showed that the CNFs were properly formed and that the CT molecules immobilized on the MCNCs presented excellent properties.After heating the composites at 60 ℃ for 3 h,the non-crosslinked and cross-linked immobilized CTs retained 51.6% and 70.7% of the initial activity,respectively,whereas the free CTs retained only 29.6% of the initial activity.In addition,non-cross-linked and cross-linked immobilized CTs retained 85.7% and 84.9% of the initial activity,respectively,after 20 days,whereas the free CTs retained only 18.8% of the initial activity.When the MCNCs were used to immobilize the CT molecules,the enzyme loading capacity was enhanced up to 6.3-fold upon cross-linking.Moreover,the immobilized CTs could be easily separated and recycled from the reaction system by a magnetic force.更多还原