Immobilisation of α-amylase on activated amidrazone acrylic fabric: a new approach for the enhancement of enzyme stability and reusability

Abstract

In this study, amidrazone acrylic fabric was applied as an immobilising support for α-amylase. The immobilised α-amylase was characterised by Fourier transform infrared spectroscopy and scanning electron microscopy. Furthermore, the optimum conditions for immobilisation efficiency, immobilisation time, reusability, kinetic parameters and pH, for the immobilisation process were examined. The study demonstrated that with 4% cyanuric chloride, and a pH of 7.0, the highest immobilization efficiency of 81% was obtained. Around 65% of the initial activity was maintained after storage at 4 °C for 8 weeks. The immobilised enzyme retained 53% of its original activity after being reused 15 times and exhibited improved stability compared with the free enzyme in relation to heavy metal ions, pH, temperature and inhibitors. The immobilised enzyme presented kinetic parameters of 2.6 mg starch and 0.65 µmol maltose/mL for K m and V max respectively, compared with 3.7 mg starch and 0.83 µmol maltose/ mL for the free enzyme. The improvements in the enzyme’s catalytic properties, stability and reusability obtained from immobilisation make amidrazone acrylic fabric support a good promising candidate for bio-industrial applications.

Preparation of Streptavidin-Coated Magnetic Nanoparticles for Specific Immobilization of Enzymes with High Activity and Enhanced Stability

“…When α-amylase was immobilized following the same procedure as pullulanase, a similar shift of optimal temperature from 35 to 40 °C was observed (Figure S1). Also, similar improvements in thermal stability have been previously reported for various immobilized enzymes. , The change in optimal temperature observed here demonstrated that immobilized pullulanase was resistant to temperature increases, probably due to the immobilization-associated modifications to the physicochemical properties of the enzyme . Thus, with respect to industrial applications, immobilized enzymes are preferable to soluble forms, as the immobilized form can withstand the high temperatures that are important for enzyme catalysis …”

Effective utilization of magnetic nano-coupled cloned β-xylanase in saccharification process

“…53 Many recent studies has showed that α-amylase and xylanase enzymes remained stable and retained 65%, 93% and 60% residual activity after immobilization with MNPs for up to 60 days at 4 °C. 54–56 Similarly, alcohol dehydrogenase and pectinase enzymes showed 75% and 87% residual activities when stored at 4 °C for 21 days and 30 days respectively. 57,58 However, one study demonstrated the stability of peroxidase enzyme at 25 °C for 60 days and hydrolase 76% for 60 days.…”

Immobilization of Catalase on Chitosan/ZnO and Chitosan/ZnO/Fe2O3 Nanocomposites: A Comparative Study

“…The biocatalyst produced via incorporating Fe 2 O 3 with CS/ZnO improved the reusability. The reduction in enzymatic activity observed during recycling could be attributed to frequent interactions between the substrate and the active site of the immobilized enzyme, distorting the active site, resulting in activity loss [30][31][32]. In several studies, immobilized catalase on Eupergit C lost about 50% of its activity after 22 cycles [33], but when using chitosan beads and chitosan bentonite beads as supports for catalase, the enzyme retained about 50% and 70% of its original activity after 20 cycles, respectively [34].…”