铁氨基黏土纳米结构脂肪酶的构筑 及催化特性

以铁氨基黏土(Fe-aminoclay)为载体, 1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐(EDC)为共价交联剂, 构筑了铁氨基黏土纳米结构脂肪酶催化剂(Feclay-lipase). 利用X射线衍射(XRD)、 透射电子显微镜(TEM)和傅里叶变换红外光谱(FTIR)等技术对Feclay-lipase进行了表征, 并通过酶动力学对比研究了游离脂肪酶和Feclay-lipase的酶学特性. 结果表明, Fe-aminoclay的载酶量为414.4 mg/g, 固定化效率可达82.88%, Feclay-lipase的酶活较游离酶提高了3倍, 最适反应温度提高了10 ℃, 最适反应 pH向碱性偏移, 储存稳定性更好, 在4 ℃下贮存30 d后其酶活无明显减弱.

Construction and Catalytic Performances of Fe-aminoclay Nanostructured Lipase ?

Lipase from Aspergillus oryzae was immobilized on Fe-aminoclay support via 1-(3-dimethylami-nopropyl)-3-ethylcarbodiimide hydrochloride(EDC) as covalent crosslinking agent. The nanocomposite structure of immobilized lipase(Feclay-lipase) was characterized by means of X-ray diffraction(XRD), transmission electron microscope(TEM) and Fourier transform infrared spectroscopy(FTIR). The enzymatic properties of free lipase and Feclay-lipase were studied by enzymatic kinetics. The results showed that the optimal immobilization efficiency of Feclay-lipase was 82.88%, immobilization capacity was 414.4 mg/g support, and the enzyme activity was 28.24 U/mg, which was three times higher than that of free lipase(8.21 U/mg). The optimum reaction temperature of Feclay-lipase increased from 45 ℃ to 55 ℃, the optimum pH shifted to alkalinity, and the catalytic activity of Feclay-lipase did not decrease significantly after storage at 4 ℃ for one month.