Escherichia coli is known to produce enterotoxins whose properties and its role in diarrheal disease has been extensively investigated. Some species of Staphylococcus are often recognized as etiological agents of many animal and human opportunistic infections. This study is the first test of change in resistance of antibiotic activity by Cordia verbenacea DC. against multiresistant strains of Escherichia coli and Staphylococcus aureus. In this study, the hexane and methanol extract of Cordia verbenacea DC. were tested for antibacterial activity alone and in combination with aminoglycosides against bacterial strains. The synergy of the methanolic and hexane were verified by microdilution method. A synergistic effect of both extracts combined with the aminoglycosides was demonstrated. It is therefore suggested that the extracts from Cordia verbenacea DC. could be used as a source of natural products derived from this plant with resistance-modifying antibacterial activity, providing a new weapon against the problem of bacterial resistance to antibiotics.Colegio de Farmacéuticos de la Provincia de Buenos Aire
