Synthesis and characterization of PMMA composites activated with starch for immobilization of L‐asparaginase

Abstract

Poly (methyl methacrylate) (PMMA)-starch composites were prepared by emulsion polymerization technique for L-asparaginase (L-ASNase) immobilization as highly activated support. The hydroxide groups on the prepared composites offer a very simple, mild and firm combination for enzyme immobilization. The pure PMMA and PMMA-starch composites were characterized as structural, thermal and morphological. PMMA-starch composites were found to have better thermal stability and more hydrophilic character than pure PMMA. L-ASNase was immobilized onto PMMA-starch composites contained the different ratio of starch (1, 3, 5, and 10 wt %). Immobilized L-ASNase showed better performance as compared to the native enzyme in terms of thermal stability and pH. K m value of immobilized enzyme decreased approximately eightfold compared with the native enzyme. In addition to, immobilized L-ASNase was found to retain 60% of activity after 1-month storage period at 4 8C. Therefore, PMMA-starch composites can be provided more advantageous in terms of enzymatic affinity, thermal, pH and storage stability as L-ASNase immobilization matrix.

Development of L-Asparaginase Biobetters: Current Research Status and Review of the Desirable Quality Profiles

“…In another work, ASNase immobilized on poly(methyl methacrylate) with starch resulted in a decrease in the apparent K M of around 8-fold compared to the value of the non-immobilized enzyme. Moreover, after 1-month storage period at 4°C the immobilized ASNase retained 60% of activity (Ulu et al, 2016).…”

Preparation of poly(eugenol-co-methyl methacrylate)/polypropylene blend by creative route approach: structural and thermal characterization

“…Copolymers PEgMMA 1:1 and PEgMMA 1:3 show a similar thermal curve to PMMA, as eugenol could not participate in polymerization at the expected level. It has been stated in the literature that PMMA may show two decay steps [36]. In the thermal curve of the PEgMMA 1:1 copolymer, where the eugenol monomer ratio is relatively high, the first degradation step is at 260 °C and the second decomposition temperature is 410 °C.…”

From ion exchange resins to polymer‐supported reagents: an evolution of critical variables

“…The active site consists of two threonine residues, one at the N‐terminal end and the other at the end of the first third of the sequence, that hold the asparagine for reaction with water. The enzyme has been immobilized onto a composite of poly(methyl methacrylate) and starch and the kinetics of the asparagine reaction followed by the evolution of ammonia . The maximum rate (V max , mg ‐1 protein) and the substrate concentration at which the reaction rate is half of V max (K m , mmol L ‐1 )) are 301 and 0.216, respectively, for the native enzyme, and 253 and 0.0256, respectively, for the immobilized enzyme.…”

“…The enzyme has been immobilized onto a composite of poly(methyl methacrylate) and starch and the kinetics of the asparagine reaction followed by the evolution of ammonia. 38 The maximum rate (V max , mg -1 protein) and the substrate concentration at which the reaction rate is half of V max (K m , mmol L -1 )) are 301 and 0.216, respectively, for the native enzyme, and 253 and 0.0256, respectively, for the immobilized enzyme. Thus while the maximum rate decreases somewhat upon immobilization, the affinity between the enzyme and asparagine increases significantly.…”