The effect of nano-calcium carbonate onβ-glucosidase immobilized by alginate and chitosan  

作　　者：Mariam Iqbal Yuefeng Deng Qiaoyue Chen Chengli Yang Yihui Zhu Ziqian Chen Jianjun Wang Kaishun Hu Guanya He Dali Li 

机构地区：[1]Department of Bioengineering,School of Environmental and Biological Engineering,Nanjing University of Science and Technology,Nanjing 210094,China

出　　处：《Green Synthesis and Catalysis》2022年第3期265-271,共7页绿色合成与催化（英文）

摘　　要：Nanotechnology has become the most promising domain to boost the efficiency of enzymes.Enzymes are vital as a green catalyst in many industries,food,pharmaceutical and biomedical,etc.The immobilization process of the enzyme increases its catalytic properties.In this research,a novel method is presented to describe the effect of nano-calcium carbonate on the characteristics of immobilizedβ-glucosidase,which was extracted from the Agrocybe aegirit.The nano-CaCO_(3)was produced using the eco-friendly natural deep eutectic solvent.The pure nano-CaCO_(3)was observed as vaterite,with a size of about 300 nm.The nano-calcium carbonate was coated by a natural polymer sodium alginate compound and then adsorbed chitosan.Further,this obtained composite is cross-linked by the bioactive genipin to immobilize theβ-glucosidase.The enzyme/protein loading ratio to the supports was 1:4,respectively.The recovery efficiency of immobilizedβ-glucosidase was 89.3%,and immobilization yield was 96.452%.Chitosan-coated nano-CaCO_(3)was used as a carrier for immobilization ofβ-glucosidase to improve its stability and reusability.In addition to stability and reusability,pH tolerance,temperature tolerance,and enzyme kinetics are the significant parameters that illustrate the proficiency of an immobilized enzyme.The measured optimal enzymatic reaction conditions for the immobilizedβ-glucosidase were 50℃and pH 6.Furthermore,it has shown noticeable improvements in thermo-stability and pH tolerance.Temperature tolerance was observed 50%to the initial activity of the immobilized enzyme even after the 3 h of incubation at 50℃,while pH tolerance was noticed more than 50%and 40%at pH 7 and 8,respectively.The K_(m)and V_(max)values of free and immobilizedβ-glucosidase to 4-nitrophenylβ-D-glucopyranoside were 1.549μmol/L/min,0.346 mmol/L and 0.532μmol/L/min,0.080 mmol/L,respectively.The immobilizedβ-glucosidase retains its storability 80%even after 30 days of storage at 4℃and maintains 93.1%of its residual activity by reusing up to 10 c

关 键 词：IMMOBILIZATION Nano-CaCO_(3) Sodium alginate CHITOSAN GENIPIN 

分 类 号：O64[理学—物理化学]