Optimization of growth and catalase production in Kocuria sp. ASB 107 in economic medium

Catalase is an enzyme capable of catalyzing the alteration of H2O2 to O2 and H2O. It has recently acquired importance due to its application in the textile industries. Kocuria ASB107shows relative high resistance against ionizing and UV radiation. the antioxidant barrier in this bacterium consists enzymes such as catalase. In order to achieve the highest rate of bacterial growth and catalase production, sugar cane molasses, sugar beet molasses and whey were used as cheap carbon sources. Growth curves were plotted and at the late logarithmic phase, fermentation product was harvested. Catalase activity was measured spectrophotometrically by monitoring the decrease in absorbance at 240 nm affected by the decomposition of hydrogen peroxide. bacterial growth was also stimated from the weight of dry biomass. The highest biomass (5.19 g/L) and catalase activity (2136.25 U/mL) were found in medium consisted 1% molasses and 2.5 % yeast extract. In addition with the 4% whey as a carbon source, catalase activity and growth were 3032.5 U/mL and 6.16 g/L respectively. The results showed molasses and whey are suitable and inexpensive substrate. on the other hand inorganic nitrogen sources such as urea are not suitable for the production of catalase and cell growth.