【摘要】 首先利用聚乙二醇8000（PEG8000）将脂肪酶激活为开放构象（PEG-Lip）,再将PEG-Lip与Ca₃（PO₄）₂共结晶制得Ca₃（PO₄）₂@PEG-Lip晶体花,然后将晶体花包覆于海藻酸钙（CA）凝胶（Gel）微球中,制得一种双重包埋激活脂肪酶的内花凝胶微球CA-Gel@Ca₃（PO₄）₂@PEG-Lip.该微球呈白色椭圆状,直径约2 mm.利用扫描电子显微镜（SEM）、X射线光电子能谱（EDS）、共聚焦显微镜（CLSM）和傅里叶变换红外光谱（FTIR）表征了其微观形貌和组成,发现脂肪酶被包埋在Ca₃（PO₄）₂晶体中,形成的Ca₃（PO₄）₂@PEG-Lip晶体花被包覆于海藻酸钙凝胶微球内的网络中.CA-Gel@Ca₃（PO₄）₂@PEG-Lip的酶学性质研究表明,在Ca₃（PO₄）₂晶体和海藻酸钙凝胶的“双层铠甲”保护下,脂肪酶的热稳定性和pH稳定性均有所改善.利用孔径约0.5 mm的滤网即可实现对凝胶微球的快速回收;循环利用10次后,酶活保留率达83%,脂肪酶的操作稳定性和重复利用性明显提高.本文为脂肪酶在食品与医药工业中的开发利用提供了新的思路与方法.更多还原

【Abstract】 Lipase was first activated to an open conformation（PEG-Lip） by polyethylene glycol（PEG8000）, then cocrystallized with Ca₃（PO₄）₂ into Ca₃（PO₄）₂@PEG-Lip crystal flowers, and then coated with calcium alginate gel to form a inner flower gel microsphere double-embedded activated-lipase[CA-Gel@Ca₃（PO₄）₂@PEG-Lip]. The gel microspheres were white and oval-shaped with a diameter of about 2 mm. Characterized by scanning electron microscopy（SEM）, energy dispersive spectrometer（EDS）, confocal microscopy（CLSM） and fourier transform infrared spectrophotometer（FTIR）, the activated lipase was embedded in Ca₃（PO₄）₂ crystals, and the Ca₃（PO₄）₂@PEG-Lip crystal flowers were entrapped in mesh pores of calcium alginate gel. Enzymatic properties showed that the heat resistance and the pH stability of CA-Gel@Ca₃（PO₄）₂@PEG-Lip were enhanced under the protection of double armors compared to free lipase. In the repeated utilization experiment, the rapid recovery of CA-Gel@Ca₃（PO₄）₂@PEG-Lip could be achieved with an aperture diameter of approximately 0.5 mm filter, and after 10 cycles, the enzyme activity was retained up to 83%, showing the obvious improvement of operational stability and reusability of the lipase. This paper provides a new idea and method for the development and utilization of lipase in food industry.更多还原