Identification and antibacterial activity of flavonoid compounds from wood branches of the pudau plant (Artocarpus kemando Miq.)

Abstract

In this research, isolation, identification, and antibacterial assay of flavonoid compounds have been carried out. These compounds were obtained from the wood branches of the pudau endemic plant from Karang Anyar village, Penengahan, South Lampung Regency, Lampung Province. Flavonoid compound extraction was carried out by maceration method using methanol, while fractionation and purification were conducted using chromatography technique. The purity of the compounds was determined by the melting point test and thin layer chromatography, the identification of compounds was assigned by UV-Vis and IR spectroscopy. The results of the isolation obtained two compounds, artocarpin (1) and cycloartocarpin (2). Compound (1), 92 mg, in the form of a yellow needle crystal with a melting point of 184.9-187.5 °C; compound (2), 20 mg, in the form of yellowish white needle crystals with melting point 280-283 °C. In the antibacterial assay against Bacillus subtilis and Escherichia coli, compounds (1) showed very strong antibacterial activity at a concentration of 0.4 mg/disk and 0.5 mg/disk, respectively, whereas compound (2) had strong antibacterial activity against B. subtilis and E. coli at the same concentration of 0.5 mg/disk.