Kinetics of immobilized alpha amylase impregnated with silver nanoparticles in Egg Shell Membrane for enhanced starch hydrolysis | ||
| Egyptian Journal of Chemistry | ||
| Volume 66, Issue 2, February 2023, Pages 1-12 PDF (1.13 M) | ||
| Document Type: Original Article | ||
| DOI: 10.21608/ejchem.2022.110860.5050 | ||
| Authors | ||
| Halima R* 1; Archna Narula2 | ||
| 1Sir M Visvesvaraya Institute of Technology | ||
| 2M.S Ramaiah Institute of Technology | ||
| Abstract | ||
| In this study, α-amylase, an industrially important enzyme was successfully immobilized on a porous eggshell membrane impregnated with silver nanoparticles and is used for a starch hydrolysis reaction. The immobilized alpha-amylase impregnated with silver nanoparticles in an eggshell membrane (IAmy/IAg-Np/ESM) was studied for its catalytic efficacy through various reactions with varying parameters like pH, temperature, and substrate concentration and using starch as a substrate. The activity of IAmy/IAg-Np/ESM was studied at various parameters like was compared with that of reaction with free enzyme and free nanoparticles with enzyme amylase. IAmy/IAg-Np/ESM showed highest Km and Vmax values (2.2 and 1.7-fold) and lower Vmax/Km ratio (1.4-fold), respectively than the free enzyme. The enzyme with free nanoparticles showed higher Km and Vmax values (1.7 and 1.1-fold) and lower Vmax/Km ratio (1.2-fold), respectively than the free enzyme. IAmy/IAg-Np/ESM and the enzyme with free nanoparticles when compared to the free enzyme, exhibited lower activation energy, higher D-values, higher half-life, lower deactivation constant rate, and higher energy for denaturation. Immobilization of α-amylase increased enthalpy (4.1-fold), free energy (1.2-fold), and decreased entropy (4.4-fold) of thermal inactivation. The enzyme with free nanoparticles increased enthalpy (3.4-fold), free energy (0.7-fold), and decreased entropy (3.2-fold) of thermal inactivation. IAmy/IAg-Np/ESM membrane was characterized by SEM and FTIR to study the structural properties and ensured the immobilization of enzyme and nanoparticles to the egg shell membrane by covalent bonding. A significant increase in pH stability of IAmy/IAg-Np/ESM was observed especially at alkaline pH values. In addition, IAmy/IAg-Np/ESM preserved 80 % of its initial activity after 15 consecutive cycles. When storing IAmy/IAg-Np/ESM at 4 °C the residual activity was 80 %, respectively after 21 days. Though enzyme with free nanoparticles also improves the kinetic properties of the enzyme, the immobilization process improved the catalytic properties and stabilities, thus raising the suitability for industrial processes with lower cost and time. | ||
| Keywords | ||
| Green synthesis; immobilized silver nanoparticles; Egg shell membrane; Enzyme kinetics; stability of membrane | ||
|
Statistics Article View: 625 PDF Download: 588 |
||
