Partial Purification of a Catalase from an Improved Nigerian Sorghum Grain Variety

Abstract

Catalases are key components of cellular detoxification pathways that prevent the formation of highly reactive hydroxyl radicals through catalyzing the decomposition of hydrogen peroxide into water and molecular oxygen. Their presence in brewery grains prevent the inactivation of important brewery enzymes and also stop lipid peroxidation. To determine their occurrence and establish some of its properties in sorghum, which has become as an important brewery grain similar to barley, crude catalase was obtained from a sorghum grain variety. Preliminary purification of catalase from the sorghum grain variety used, NRL-3, showed that the enzyme was purified 3.2-fold from the crude protein to give a 49% yield of the partially purified enzyme, with a final specific activity of 32 Umg-1 proteins. There was also a positive indication of sorghum catalase presence on SDS PAGE with positive bands occurring between the range of 48-62 kDa. Therefore, the molecular weight of sorghum catalase most likely falls within the two bands. The enzyme showed a narrow pH range with optimum activity occurring at pH 7. Similarly, its optimum activity temperature occurred at 40°C.  This work is the first reported attempt at purifying catalase from sorghum.