PENENTUAN AKTIVITAS ENZIM URIKASE PADA HOMOGENAT HATI IKAN GURAMI (Osphronemus goramy) DAN HATI IKAN NILA (Oreochromis niloticus)

• Main Author: Yuharsiwi, Desyana
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/44134
• Institution: Institut Teknologi Bandung

Gourami fish (Osphronemus goramy) and nile tilapia fish (Oreochromis niloticus) are two species of fish that are often consumed in Indonesia. The presence of uricase enzyme in several saltwater fish's liver had been proven on several researches, but the presence of uricase enzyme on freshwater fish is still not widely known. This research is done in order to find out the presence of uricase enzyme in gourami's liver and nile tilapia's liver homogenate. Homogenates are made by homogenizing samples in buffer medium with mortar and pestle. The presence of uricase in samples are then examined with enzymatic reaction as the result of mixing samples and uric acid stocks. The result of the examination then tested with UV-spectrophotometer where the uric acid level based on the absorbance is used as an indicator of the enzymatic reaction. Determination of optimum temperature in three temperature groups (25°C, 30°C, 37°C) and optimum pH in four pH group (7, 8, 9, 10) are resulted in 37°C as the optimum temperature and pH 9 as the optimum pH. The activity of enzymes from both samples are proven by the linear absorbance result in examinations with various sample concentration with R² value of 0.9993 for gourami fish sample and R² value of 0.9927 for nile tilapia fish sample. The value of Vmax and KM that are obtained from the gourami fish's liver homogenate are respectively 1.258 µmol/min and 117.929 mg/L whereas the value of Vmax and KM that are obtained from the nile tilapia fish’s liver homogenate are respectively 0.837 µmol/min and 49.431 mg/L.