Antibacterial coumarins isolated from Launaea resedifolia

From the aerial parts of Launaea resedifolia, four coumarin compounds were isolated from the methylene chloridemethanol (1 : 1) extract, namely, cichoriin I, esculetin II, scopoletin III and isoscopoletin IV. The structures of the compounds were elucidated by 1D, 2D-NMR and HR-CIMS analysis. These compounds showed high antibacterial activity against some Gram positive bacteria as Bacillus cereus and Staphyllococcus aureus in minimum inhibitory concentrations of 200 and 400 µg/mL. However, they showed no effect on tested Gram negative bacteria as Serratia Sp, Pseudomonas Sp and Escherichia coli ).