ISOLASI SENYAWA ANTIOKSIDAN DAUN JAMBU BOL (SYZYGIUM MALACCENSE L.)

• Main Author: Nurhasanah, Santi
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/45061
• Institution: Institut Teknologi Bandung

Free radicals are compounds that have one or more unpaired electrons on its outermost orbital. The existence of this unpaired electrons causing the free radicals to be more reactive and unstable. Excessive amounts of free radical entering the body can leads to degenerative disease. Antioxidants are compounds that play a role in inhibiting oxidative reaction by binding to free radicals and converts them into non-radical compounds. Based on research, one of the plants that known having antioxidant activity is Malay Apple (Syzygium malaccense L.). This study aims to determine the IC50 DPPH (2.2-diphenyl-1pikrilhidrazil) from each leaf extract and to isolate and characterize the compounds that have antioxidant activity in Malay Apple leaves. Extraction was done by reflux method using three solvent with increasing polarity, i.e. n-hexane, ethyl acetate and ethanol. Each extract was monitored by thin-layer chromatography (TLC). Determination of IC50 DPPH of each extract are done using ultraviolet-visible spectrophotometry. The ethanol extract was fractionated by paper chromatography and the third fraction are continued to the next stage that is subfractionation using paper chromatography method. Subfraction then purified by preparative thin layer chromatography, followed by the purity test of the isolate using thin layer chromatography (TLC) methods and the isolate is characterized. The crude drug of Malay Apple leaves contain flavonoid, phenols, tannins, saponins, steroids / triterpenoids and terpenoids compounds. Quantitative test results showed that ethanol extract has the strongest activity with the lowest IC50 values of 25.61 ± 0.40 µg / ml followed by ethyl acetate extract with IC50 values of 109.29 ± 2.56 µg/ml and the lowest is n-hexane extract with IC50 values of 3084.99 ± 7.89 µg/ml. The characterization of the isolate using paper chromatography shows that the isolated antioxidant compound is suspected as a dihydroflavonol aglycon.