Inmovilización de pectinasa por absorción en matriz de quitina recubierta con alginato
Aspergillus niger pectinase was immobilized on an alginate-coated chitin support by adsorption. The optimal conditions for immobilization were: pH 4.5, time of incubation 2 h and 85 μg/mL protein concentration. The yield of immobilized protein was 70 % and the enzyme retained 60 % of the initial activity. Optimal pH, heat stability and reusability were evaluated, among other properties of the immobilized enzyme. The thermostability was enhanced by about 9.7 °C after immobilization. The immobilized pectinase was resistant during incubation, 10-fold more resistant to thermal treatment at 50 oC than the native enzyme. The optimal pH for the catalytic activity of both, the immobilized pectinase and the free enzyme, was the same, the prepared biocatalyst retaining 50 % of the original catalytic activity after 9 cycles of reuse. The obtained bioconjugate showed good operational stability and improved thermostability. These properties support the potential application of the immobilized pectinase at the juices industry.