Indonesian propolis: chemical composition, biological activity and botanical origin

From a biologically active extract of Indonesian propolis from East Java, 11 compounds were isolated and identified: four alk(en)ylresorcinols (obtained as an inseparable mixture) (1-4) were isolated for the first time from propolis, along with four prenylflavanones (6-9) and three cycloartane-type triterpenes (5, 10 and 11). The structures of the components were elucidated based on their spectral properties. All prenylflavanones demonstrated significant radical scavenging activity against diphenylpicrylhydrazyl radicals, and compound 6 showed significant antibacterial activity against Staphylococcus aureus. For the first time Macaranga tanarius L. and Mangifera indica L. are shown as plant sources of Indonesian propolis.