Uji Aktivitas Antioksidan Fraksi Etil Asetat dan Identifikasi Golongan Senyawa Flavonoida dari Kulit Buah Srikaya Hijau (Annona squamosa. L)

Abstract

Green soursop.(Annona squamosa. L) is oneyof the tropical plants that is often used in traditional medicine and has a content of secondaryymetabolite compounds, including flavonoids that have the potentialyas natural antioxidants. This study aims to test the antioxidant.activity and identify the flavonoid.compound group from the skin of green soursop fruit (Annona squamosa. L). Green.soursop (Annona squamosa. L) fruit.skin as much as 3000/gram was macerated with methanol, followed by partition extraction using ethylyacetate and n-hexane. The.extract was then purified using column chromatographyywith silica.gel as the stationary yhase and.chloroform: ethyl acetate as the mobile.phase and preparative thinylayer chromatographyywas carried out. The pure compoundyobtained was an amorphous solidywith a yellowish orange color as much as 7 mg with an Rf value of 0.44. Based on the results of UV-Vis spectroscopy, it showed two absorption peaks at 262 nm and 360 nm. FT-IR spectroscopy showed theypresence of O-H, C-Hysp3 stretch, C=O ketone, C=C aromatic, C-H bend, C-O-C, and C-H sp3 bend groups. Proton Nuclear Magnetic Resonance Spectroscopy (1H-NMR) showed the presence of protons H-6’, H-5’, H-2’, H-8, H-6. Based on the analysis data, the isolated compound is a flavonoid compound of the flavonol group. Antioxidantyactivity test using the DPPHymethod showed that this compound has a fairly high ability to capture free radicals, with the highest inhibition value of 92.58% and anyIC50yvalue of 41.14 ppm. Based on these results, green soursopyfruit skin has theypotential as a naturalysource of antioxidants from the flavonoid group.