title: Improved performance of α-amylase immobilized on poly(glycidyl methacrylate-co-ethylenedimethacrylate) beads.
abstract: α-Amylase was successfully immobilized onto poly(glycidyl methacrylate-co-ethylenedimethacrylate) (PGMA/EDMA) beads with high immobilization efficiency of 87.8%. PGMA/EDMA beads with a relatively uniform diameter of 2-3 μm were prepared by single-step swelling polymerization. After amination with ethanediamine and activation with glutaraldehyde, PGMA/EDMA beads showed commendable α-amylase immobilization capacity of 35.1 mg g(-1) carrier. Compared with free form, immobilized α-amylase had increasement of 12.94 mg mL(-1) for Km and 0.124 mmol mL(-1) min(-1) for Vmax, improved acid resistance (the optimal pH from 7 to 5), presented better thermal stability by retaining 61% activity than 40% at 90 °C, and displayed high operational reusability by retaining 58% of its initial activity after nine uses. Moreover, less than 10% of the free enzyme and more than 80% of the immobilized enzyme retained activity after 180 min pre-incubation at 50 °C. The easy modification, high immobilization efficiency and good properties of immobilized α-amylase in the present study indicate that PGMA/EDMA beads are suitable for α-amylase immobilization. The enhancement of acid resistance and thermo stability is doubtless of benefit for the industrial use of α-amylase.
authors: Key Laboratory of the Ministry of Education for Medicinal Resource and Natural Pharmaceutical Chemistry, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
authors: Tian
authors: T
authors: He
authors: Key Laboratory of the Ministry of Education for Medicinal Resource and Natural Pharmaceutical Chemistry, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
authors: Yong-Le
authors: YL
authors: Tian
authors: Key Laboratory of the Ministry of Education for Medicinal Resource and Natural Pharmaceutical Chemistry, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
authors: Liang
authors: L
authors: Qi
authors: Key Laboratory of the Ministry of Education for Medicinal Resource and Natural Pharmaceutical Chemistry, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China.
authors: Jing
authors: J
authors: Zhang
authors: Key Laboratory of the Ministry of Education for Medicinal Resource and Natural Pharmaceutical Chemistry, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an 710062, China. Electronic address: zqzhang@snnu.edu.cn.
authors: Zhi-Qi
authors: ZQ
authors: Zhang
mesh_terms: D000818:Animals; D001407:Bacillus / Q000201:enzymology; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008768:Methylmethacrylates / Q000737:chemistry*; D008863:Microspheres; D008958:Models, Molecular; D011487:Protein Conformation; D013696:Temperature; D000516:alpha-Amylases / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D004800:Enzymes, Immobilized; D008768:Methylmethacrylates; C020347:GMA-EDMA; D000516:alpha-Amylases
keywords: Amylase; Immobilization; Poly(glycidyl methacrylate-co-ethylenedimethacrylate) beads