#TITLE_ALTERNATIVE#

• Main Author: KARTIKA (NIM , IKEU
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/8186
• Institution: Institut Teknologi Bandung

Catalase (EC 1.11.1.6), is an enzyme catalyzing the decomposition of hydrogen peroxide into molecular oxygen and water have been extracted from peroxisome of the potato tubers cell. The first extraction step was homogenizing the potato tubers by using a blender, and then centrifuged them for 30 minutes at 20.000 g. Catalase activity and total protein concentration of the resulted crude extract were determined by Aebi and Bradford methods, respectively. The total catalase activity was 47958.3 units and total mass of proteins was 14001.39 mg, thereby its specific activity was 3.425 units/mg of protein. Purification of the crude extract was started by fractionation of ammonium sulfate. The results revealed that the fraction of 20-80% saturation exhibited a highest specific activity e.g. 7.17 units/mg of proteins with the yield of 41.15 % and the purity level was approximately as twice as its crude extract. Further purification step was conducted by applying the ammonium sulfate fraction into DEAE-cellulose column. NaCl gradient concentration was used as an eluent. The collected fractions were determined for its total catalase activity and protein concentration. The highest specific activity reached 57.88 units/mg of proteins with the yield of 27, 92 % and the purity level was approximately seventeen times larger than the origin crude extract. After concentrated the pure enzyme by lyophilizes then we applied it to SDS-PAGE and found that the molecular weight of the enzyme was about 59 kDa. Determination of the kinetic parameters of the pure enzyme gave Vmaks and KM about 4, 89 Ms-1 and 1.13 x 10-3 M, respectively. Besides, the above experiment, we also modified the simple methods for measuring kinetic parameters of catalase as described in the preparatory problems 36 of International Chemistry Olympiad (IChO) 2006. We demonstrated such method to high school teachers in collaboration with MGMP Kota Bandung and also to students in several high schools in Bandung. We analyzed their interest through the questioners given to them. We found that teachers and students were interested.