PURIFIKASI DAN KARAKTERISASI ENZIMATIK SUPEROKSIDA DISMUTASE Citrus hystrix, DC., TANAMAN ASAL INDONESIA

• Main Author: Fajrul Ihsan, Ardika
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/45414
• Institution: Institut Teknologi Bandung

Superoxide dismutase (SOD, EC 1.15.1.1) is endogenous antioxidant protein which catalyzes dismutation of superoxide anion into hydrogen peroxide and oxygen, and used as an active pharmaceutical compound. In previous study, screening activity of SOD has been conducted on several tropical fruits resulting SOD from Citrus hystrix, DC. (kaffir lime) had the highest activity. Study about SOD from this species has not been conducted, and this plant is originally from Indonesia. The purpose of this study is to purify and to characterize SOD Citrus hystrix, DC. First step was preparation of crude protein from fruit of kaffir lime. The whole part of fruit was blended with phosphate buffer, filtered juice was precipitated by ammonium sulfate and its precipitant was dialyzed. Next process was purification step using gel filtration chromatography Sephadex G50 column. SOD activity assay was done by measuring reduction of nitro blue tetrazolium (NBT) that monitored by colorimetry and zymography. Characterization of purified SOD in this study was including determination of specific activity, molecular weight, metal ion cofactor, optimum pH and temperature, pH and thermal stability, and stability against certain chemical compounds. Purified SOD was obtained in the first fraction of gel filtration chromatography with 90.9% purity and 8.84% yield, had 26.65 kDa in size and displayed 1509.31 U/mg specific activity. Determination of metal ion cofactor type showed that SOD from this species was Cu/Zn-SOD or Mn-SOD. Optimum temperature and pH of the SOD were 60 ?C and 6 respectively. SOD was stable within range 20-80 ?C and still showed activity greater than 60% within pH 4-9. SOD stability against certain chemical compounds was influenced by concentration and exposed time length. Purification and enzymatic characterization of SOD Citrus hystrix, DC. has been successfully done in this research. SOD Citrus hystrix, DC. from this research had good thermal pH and temperature stability which suitable for general pharmaceutical products formulation.