Background: The development and spread of resistance by bacteria to existing antibiotics are becoming more common nowadays. Considering the ethnopharmacological relevance of Palisota ambigua (Commelinaceae), this study was designed to investigate the antibacterial activities of chemical constituents of P. ambigua against two Gram-positive (Staphylococcus aureus ATCC 25923 and Streptococcus pneumoniae ATCC 49619) and two Gram-negative (Escherichia coli ATCC 8739 and Klebsiella pneumoniae 109 (iso...