Graduate Program in Chemical Engineering, Federal University of Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil; Department of Chemical Engineering, School of Engineering, Federal University of Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.
Department of Chemistry, Federal University of Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil.
Int J Biol Macromol. 2018 Dec;120(Pt B):2354-2365. doi: 10.1016/j.ijbiomac.2018.08.190. Epub 2018 Sep 1.
Ion-exchange supports have been prepared via sequential functionalization of silica-based materials with (3‑Glycidyloxypropyl)trimethoxysilane (GPTMS) (Epx-SiO) and activation with glycine (Gly-Epx-SiO) in order to immobilize lipase from Thermomyces lanuginosus (TLL) via adsorption. Rice husk silica (RHS) was selected as support with the aim of comparing its performance with commercial silica (Immobead S60S). Sequential functionalization/activation of SiO-based supports has been confirmed by AFM, SEM and N adsorption-desorption analyses. Maximum TLL adsorption capacities of 14.8 ± 0.1 mg/g and 16.1 ± 0.6 mg/g using RHS and Immobead S60S as supports, respectively, have been reached. The Sips isotherm model has been used which was well fitted to experimental data on TLL adsorption. Catalytic activities of immobilized TLL were assayed by olive oil emulsion hydrolysis and butyl stearate synthesis via an esterification reaction. Hydrolytic activity of the biocatalyst prepared with a commercial support (357.6 ± 11.2 U/g) was slightly higher than that of Gly-Epx-SiO prepared with RHS (307.4 ± 7.2 U/g). On the other hand, both biocatalysts presented similar activity (around 90% conversion within 9-10 h of reaction) and reusability after 6 consecutive cycles of butyl stearate synthesis in batch systems.
已通过硅基材料与（3-缩水甘油丙基）三甲氧基硅烷（GPTMS）（Epx-SiO）的顺序功能化以及与甘氨酸（Gly-Epx-SiO）的活化来制备离子交换载体，以通过吸附固定来自Thermomyces lanuginosus（TLL）的脂肪酶。选择稻壳硅（RHS）作为载体，目的是将其性能与商业硅（Immobead S60S）进行比较。通过 AFM、SEM 和 N 吸附-解吸分析证实了基于 SiO2 的载体的顺序功能化/活化。分别使用 RHS 和 Immobead S60S 作为载体，达到了 TLL 的最大吸附容量为 14.8±0.1mg/g 和 16.1±0.6mg/g。使用 Sips 等温线模型对 TLL 吸附的实验数据进行了很好的拟合。通过橄榄油乳液水解和通过酯化反应合成丁酸硬脂酸酯来测定固定化 TLL 的催化活性。商业载体（357.6±11.2U/g）制备的生物催化剂的水解活性略高于 RHS 制备的 Gly-Epx-SiO（307.4±7.2U/g）。另一方面，两种生物催化剂在间歇体系中进行 6 次连续丁酸硬脂酸酯合成循环后，在 9-10 小时的反应时间内转化率接近 90%，具有相似的活性和可重复使用性。
