The hexane fractions from methanolic extracts of Anetheum graveolens L. (Umbelliferae) and Acorus gramineus Soland. (Araceae), revealed potent inhibitory activities against the resistance of multi-drug resistant Staphylococcus aureus SA2 when combined with ampicillin (Am) or chloramphenicol (Cm). As active principles, carvone and the liquid mixture containing carvone from Anetheum graveolens L. and a liquid mixture mainly consisting of benzoic acid phenylmethyl ester (benzyl benzoate) from Acorus gramineus Soland, were identified. They showed resistance inhibition at the level of 20-50 micrograms/ml when combined with 100 or 50 micrograms/ml of Am or Cm, respectively.