Study On Catalytic Conversion Of 5-Hydroxymethylfurfural By Immobilized Trienzyme

5-Hydroxymethylfurfural(HMF),as a platform compound,is mainly derived from biomass materials.Because HMF has the characteristics of easy catalysis,it is widely used in medicine,material synthesis and other fields.In this thesis,galactose oxidase(GOase),which is widely used as a catalytic substrate,is used to catalyze the oxidation of HMF,and hydrogen peroxide(H2O2)is produced as a by-product.The presence of H2O2 can cause inhibition or even inactivation of GOase,so manganese superoxide dismutase and catalase(MnSOD and CAT)were introduced in the study to decompose the by-products in order to eliminate the negative effects caused by H2O2.In this paper,Cu2+ ions were used to complete the immobilization of the above three enzymes in PBS buffer.The immobilized trienzyme(GOase/MnSOD/CATCu)was observed to present a hydrangee-type structure by SEM.By means of characterization such as EDS and confocal laser scanning,it can be seen that the three enzymes as well as copper elements are distributed in the internal structure of the complex.In the study of HMF catalytic activity using immobilized trienzyme,the ratio optimization between GOase and CAT,GOase and MnSOD and CAT was accomplished in this paper.In addition,the effects of single and double enzyme immobilization system,free single enzyme system,H2O2 addition,and the reproducibility of immobilized triple enzyme were also studied.The results showed that the catalytic efficiency of the three enzyme immobilization system was better than that of the single and double enzyme immobilization system and the free single enzyme system;the low concentration of H2O2 had a certain promoting effect;the reuse of the immobilized three enzymes did not affect its catalytic efficiency.