Thermal deactivation studies of alpha-amylase immobilized onto core-shell structured aniline formaldehyde crosslinked polyaniline magnetic nanocomposite

Aniline Formaldehyde Cross-Linked Polyaniline Magnetic Nanocomposite with Core-Shell Structure As A New Platform for Enzyme Immobilization

“…The reaction's incubation temperature fluctuated between 30 -60 0 C. (Supplementary data-Appendix D-Figure D2). The relative activity obtained was 86% when the enzyme was immobilized, which shifts its optimal temperature from 50 0 C to 40 0 C, which can be related to a change in the structural integrity of the enzyme structure, which promoted improved amylase activity below 50 0 C. Otherwise, the protein structure may have been altered by the attachment to the support, and higher temperatures may have resulted in the denaturation of the enzyme due to the breakdown of non-covalent intramolecular interactions.The immobilized enzyme exhibited a broad and stable temperature profile and retained more than 50 % activity even at 60 0 C. This can be ascribed to the protective effect provided by the enzyme support at higher temperatures where denaturation occurs (19,24) . The activation energy of immobilized amylase and free amylase for the hydrolysis of the starch substrate can be obtained from the Arrhenius plot for Free enzyme and immobilized enzyme shown in Figure 1.…”

“…Using starch as a substrate, Fuwa's method was used to determine the activity of the immobilized and free enzymes (18,19) (Supplementary data -Appendix A4).…”

“…Immobilization parameters such as pH, contact period, initial amount of protein and temperature were optimized (Supplementary data -Appendix C1-C4) and evaluated the immobilization yield, activity yield, and immobilization efficiency of the immobilized enzyme (Table 1) (19,24) . The maximum activity was observed at immobilization pH 7, contact period of support and enzyme at 60 minutes, initial amount of protein of 1mg and immobilization temperature of 40 • C were taken as the optimum immobilization parameter.…”

“…The maximum activity was observed at immobilization pH 7, contact period of support and enzyme at 60 minutes, initial amount of protein of 1mg and immobilization temperature of 40 • C were taken as the optimum immobilization parameter. (19,25,26) .…”

“…The immobilized enzyme's structural configuration may alter as a result, increasing the enzyme's activity at higher pH levels. The immobilized enzyme exhibited promising pH stability across a wide pH range, which might be attributed to the enzyme's multipoint attachment to the support surfaces (12,19) .…”