Conjugation of Candida rugosa lipase with hydrophobic polymer improves esterification activity of vitamin E in nonaqueous solvent  

作　　者：Xiaoyun Hou Qinghong Shi 

机构地区：[1]Department of Biochemical Engineering,School of Chemical Engineering and Technology,Tianjin University,Tianjin 300350,China [2]Key Laboratory of Systems Bioengineering and Frontiers Science Center for Synthetic Biology(Ministry of Education),Tianjin University,Tianjin 300350,China [3]Haihe Laboratory of Sustainable Chemical Transformations,Tianjin 300192,China

出　　处：《Chinese Journal of Chemical Engineering》2023年第10期182-191,共10页中国化学工程学报（英文版）

基　　金：financially supported by the National Key Research and Development Program of China (2021YFC2102801);National Natural Science Foundation of China (21878221);the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (21621004);the Haihe Laboratory of Sustainable Chemical Transformations for financial support.

摘　　要：We described a novel polymer-lipase conjugate for high-efficient esterification of vitamin E using vitamin E and succinic anhydride as the substrates in nonaqueous media.In this work,the monomer,N-isopropylacrylamide(NIPAM),was grafted onto Candida rugosa lipase(CRL)to synthesize poly(NIPAM)(pNIPAM)-CRL conjugate by atom transfer radical polymerization via the initiator coupled on the surface of CRL.The result showed that the catalytic efficiencies of pNIPAM-CRL conjugates(19.5-30.3 L·s^(-1)·mmol^(-1))were at least 7 times higher than that of free CRL(2.36 L·s^(-1)·mmol^(-1))in DMSO.It was attributed to a significant increase in Kcat of the conjugates in nonaqueous media.The synthesis catalyzed by pNIPAM-CRL co njugates was influenced by the length and density of the grafted polymer,water content,solvent polarity and molar ratio of the substrates.In the optimal synthesis,the reaction time was shortened at least 7 times,and yields of vitamin E succinate by pNIPAM-g-CRL and free CRL were obtained to be 75.4%and 6.6%at 55℃after the reaction for 1.5 h.The result argued that conjugation with pNIPAM induced conformational change of the lid on CRL based on hydrophobic interaction,thus providing a higher possibility of catalysis-favorable conformation on CRL in nonaqueous media.Moreover,pNIPAM conjugation improved the thermal stability of CRL greatly,and the stability improved further with an increase of chain length of pNIPAM.At the optimal reaction conditions(55℃and 1.5 h),pNIPAM-g-CRL also exhibited good reusability in the enzymatic synthesis of vitamin E succinate and kept~70%of its catalytic activity after ten consecutive cycles.The research demonstrated that pNIPAM-g-CRL was a more competitive biocatalyst in the enzymatic synthesis of vitamin E succinate and exhibited good application potential under harsh industrial conditions.

关 键 词：Candida rugosa lipase POLYMERS BIOCATALYSIS ESTERIFICATION Vitamin E succi 

分 类 号：TQ426.97[化学工程]