Studies on Purification and Kinetics of Glucose Isomerase on Hydrolysates of Starch

Glucose isomerase was produced from Streptomyces phaeochromogenes by aerobic fermentation at 28°C for 24 h. The crude enzyme was obtained by disintegrating the harvested cells. Ammonium sulphate at a saturation of 0.65 gave the maximum enzyme recovery 89.4%) from the crude extract, while acetone gave 66.4% at a concentration of 3/1 (v/v). The crude enzyme extract was purified by concentration, dialysis, precipitation with ammonium sulphate, passing through a column of Amberlite, and then the eluate was treated with acetone to precipitate the enzyme. The kinetic behavior was studied and it was found that optimum D ‐glucose concentration was 0.8‐ M . No change in K m value was observed, while V max was affected.