Qian Junqing, Huang Aomei, Zhu Hanxiao, Ding Jing, Zhang Wei, Chen Yan
College of Pharmaceutical Sciences, Zhejiang University of Technology, 18, Chaowang Road, Hangzhou, 310014, People's Republic of China.
Bioprocess Biosyst Eng. 2023 Jan;46(1):25-38. doi: 10.1007/s00449-022-02810-z. Epub 2022 Nov 12.
In this study, Candida antarctica lipase B was immobilized on silica (SiO) nanoparticles by physical adsorption, and then cross-linked with glutaraldehyde (GA) to prepare cross-linked immobilized lipase (CLIL). During the condition of 1.28 mg/mL lipase concentration, 25 ℃ temperature, 2 h adsorption time, 0.01% GA (V/V) 7.5 mL and 2 h cross-linking time, the highest recovery activity of CLIL reached 87.82 ± 0.07% (22.55 ± 0.025 U/mg). Scanning electron microscope (SEM) and confocal laser scanning microscope (CLSM) confirmed that lipase was immobilized on the surface of SiO nanoparticles. The changes in secondary structures of CLIL indicated that cross-linking changed the secondary structure of lipase protein, which made the structure of CLIL more stable. Compared with the free lipase, the thermal stability and storage stability of CLIL was significantly improved, and the t at 60 °C was extended. Studies had shown that it was a feasible method to obtain CLIL by cross-linking after adsorbing lipase on SiO nanoparticles.
在本研究中，南极假丝酵母脂肪酶B通过物理吸附固定在二氧化硅（SiO）纳米颗粒上，然后与戊二醛（GA）交联以制备交联固定化脂肪酶（CLIL）。在脂肪酶浓度为1.28 mg/mL、温度为25℃、吸附时间为2 h、GA浓度为0.01%（V/V）7.5 mL且交联时间为2 h的条件下，CLIL的最高回收活性达到87.82±0.07%（22.55±0.025 U/mg）。扫描电子显微镜（SEM）和共聚焦激光扫描显微镜（CLSM）证实脂肪酶固定在SiO纳米颗粒表面。CLIL二级结构的变化表明交联改变了脂肪酶蛋白的二级结构，使CLIL的结构更稳定。与游离脂肪酶相比，CLIL的热稳定性和储存稳定性显著提高，60℃下的半衰期延长。研究表明，将脂肪酶吸附在SiO纳米颗粒上后进行交联是获得CLIL的一种可行方法。
