Isolasi dan Identifikasi Golongan Senyawa Flavonoida Serta Uji Aktivitas Antibakteri dari Daun Tumbuhan Kanyere Badak (Bridelia glauca Blume) (Phyllanthaceae)

Abstract

Flavonoid compound had been isolated from 2100 gram Kanyere Badak leaves (Bridelia glauca Blume). Samples were extracted by maceration with methanol as a solvent, then the concentrated methanol extract was dissolved with distilled water and partition extracted with ethyl acetate. The concentrated ethyl acetate extract was dissolved with methanol and the partition extracted again with n-hexane. The concentrated methanol extract was separated by column chromatography with increasing the polarity eluent (90:10; 80:20; 70:30; and 60:40) v/v. Fractions 136- 158 were combined, preparative thin layer chromatography was carried out and crystallized to obtain 4 mg of isolated yellow compound with value of Rf 0,55. Based on analysis of the UV-Visible spectrophotometer which showed wavelength (λmax) 268 nm. Spectrophotometer Infrared ( FT-IR ) spectrum showed the presence of OH, C=C aromatic, C=O ketone, C-H, C-O-C and C-O. Proton Nuclear Magnetic Resonance Spectrophotometer ( ¹H - NMR ) showed the presence of H-3, H-2’, H-6’, H-3’,and H-5’ protons and methoxy protons . The combined analysis results was suggesedt that the compound isolated is a flavonoid compound from hydroflavanone group. The total flavonoids obtained were also tested for antibacterial activity against Stapylococcus aureus and Escherichia coli bacteria through the disc diffusion method with a comparison of sample concentrations (750, 500, 250,dan 100). The diameter of inhibition zone on S. aureus bacteria (12,6; 12,4; 11,3; and 9,2) and E. coli bacteria (14,5; 12,8, 12,1; and 12,1) indicate that the samples was active or strong in inhibiting the bacteria.