Isolation and Characterization of an Antioxidant Compound from Kayu Hitam Leaves (Diospyros celebica Bakh.F.)

Isolation and characterization of an antioxidant compound from kayu hitam leaves (Diospyros celebica Bakh.F.) had been done by extraction and column chromatography method. Kayu hitam leaves powder was extracted with methanol and methanol extract reextracted with aquadest. Aqudest extract was partitioned with ethyl acetate and ethyl acetate extract repartitioned with n-hexane. The residues which are phenolic compounds were separated by column chromatography (SiO2, chloroform: methanol 90:10, 80:20, 70: 30,60: 40). The isolate obtained was purified with a preparative thin layer chromatography and obtained 9.5 mg of pure isolate in the form of yellow solid. characterization of pure isolate was determined by UV-Vis, FT-IR and 1H-NMR spectroscopic analysis. Based on the analysis carried out it can be characterized that the pure isolate obtained is methyl gallate. The antioxidant activity of methyl gallate was determined based on the DPPH free radical scavenging method. The activity of the methyl gallate was classified as strong with IC50 value of 4.41 μg / mL.