Pemurnian Parsial Dan Karakterisasi Glukosa Oksidase dari Isolat Aspergillus niger (IPBCC.08.610)

Abstract

The increasing application of enzymes in industry, healthcare and energy initiates production rise of enzymes from microorganisms, one of them are glucose oxidase from Aspergillus niger, which is now develop as enzymatic fuel cell. The aim of this study was to purified and characterized the enzyme glucose oxidase from Aspergillus niger (IPBCC.08.610). Partial purification using amonium sulfate precipitation and then followed by dialysis. The purification fold of dialysis enzyme was 6.17, specific activity enzyme was 43.17 Umg-1. In addition, the activity of glucose oxidase was stable at 25 oC. However, the result of ion stabilization of the enzyme showed that the activity of glucose oxidase reduced by the presence of Ag+ ion with relative activity was 4.8% in 1 mM and 2.1% in 5 mM. Thiourea inhibit the relative activity to 58.44% in 1 mM. On the other hand, the molecular weight of enzyme unit was estimated 160 kDa and there are 2 protein subunits of the glucose oxidase with approximately molecular weight 80 kDa. At the end, in the aspect of enzyme kinetics, glucose oxidase had Km and Vmaks value (glucose as a substrate) respectively 43 mM and 33.67 Umg-1