| Chirality is the essential attribute of nature, no matter the biological macromolecules such as protein, DNA and RNA or the spin of the planet in the universe all have the chiral characteristic. Chiral drug plays significant roles in medical and agricultural field. The difference of enantiomers shows not only in physical and chemical and pharmacological properties, more importantly, in biological activity. Chiral alcohols compounds in the synthesis of chiral drugs, chiral pesticides and high-performance liquid crystal materials and so on have important application value, Therefore, the synthesis of single chiral alcohol has important theoretical and practical meaning.Lipase enzyme has served as biological catalyst for a long time based on its stereoselectivity of chiral alcohol compound. Furthermore, the advantages of mild catalytic conditions and environment friendly has drove lipase enzyme used in various fields. However, the drawbacks of lipase enzyme hugely limit its industrial application, for example, bad stability and difficulty of recycling and so on. Immobilized enzymes technology can solve these issues to some extent, therefore the study of immobilized enzymes technology has dominated enzyme engineering technologies for ages.Sol-gel approach of immobilized enzymes is the progress of physical encapsulated progress essentially. Organic precursor composed of organic silane compound(TMOS or TEOS) is mixed with biological macromolecule uniformly in liquid phase. The mixed solution will form stable sol system through hydrolysis and condensation. Sol system gradually solidified to three-dimension network structure. Sol-gel approach follows several steps below in common ways:hydrolysis, condensation, gelation, aging and drying. Sol-gel approach of immobilized biological macromolecules have characteristics of efficiency, good repeatability and carrier can decorate.This paper firstly obtained abundance LipA raw proteins followed by ultrasonic treatment, ammonium sulfate precipitation and Hitrap Sepharose. Purified LipA was used into immobilized study. We study found propyltrimethoxysilane and tetraethoxysilane employed as precursor shows the most powerful specific activity. Of these, molar ratio between substrates, enzyme amount, amount of crosslinking agent are the most important parameters in our experiment. Through separate study on each factors, we found when the molar ratio is 4/1, enzyme amount is 300ul, crosslinking agent is 200ul, hydrolysis time is 30mins, the specific activity of LipA immobilized is 1.5 times more than free LipA.Secondly, we resolve three representative chiral alcohol compounds using immobilized protein LipA. Proper substrates of resolution have been found through the analysis of relationship between structures of substrate and catalytic activity of immobilized protein. The experiment founded this immobilized enzyme to 2-methyl-l-butanol has the better catalytic activity,and stereoselectivity of immobilized enzyme has improved than free enzyme.At the meantime, various length of acyl donor,temperature, PH, water activity all can impact esterification. Through continuous conditional optimization,We found when the donor is vinyl butyrate, temperature is 50 degree, PH is 9.5, water activity is 0.54, we can get the highest stereo selective E value of LipA enzyme is 13.05, furthermore, when reaction transformation ration is 64.13%, the optical purity is up to 97%.Thirdly, we also study the repeating utility of LipA and the final result shows LipA keeps high activity through eight times repeating routes, its relatively activity is the original activity 70%. The great recycling capability laid the foundationfor future industrial application.
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