The use of medicinal plants in treating diseases (herbal medicine) is a practice of many peoples, being done since ancient times. Several studies are conducted to determine the effectiveness of these plants, but the existence of interactions and interference with their combined use, whether beneficial or detrimental to the body, are unknown. In order to discover the existence of these interactions or interferences in the activity of the antibiotic amoxicillin, we tested in this research Punica granatum and Plantago major against Staphylococcus aureus and Escherichia coli. The raw material was obtained in the regions of Montes Claros and Curvelo, and their aqueous extracts were obtained from decoction. The minimum inhibitory concentration (MIC) of the extracts was determined by the broth microdilution technique. For interference, we performed the disk diffusion test. In the broth microdilution test, Punica granatum had MICs of 6.25% against S.aureus and 25% against E. coli. The Plantago major extract showed no activity against the bacteria. The disk diffusion test confirmed the existence of interactions and only four significant results (amoxicillin + pure Punica granatum (PgP), amoxicillin + Punica granatum dilution 1 (PgD1) and amoxicillin + Punica granatum dilution 2 (PgD2) against E. coli and amoxicillin + PgP against S. aureus). We conclude, as a result, that there really is interaction between the extracts themselves and between the extracts and amoxicillin, which can also occur with other antibiotics and cause some risk to the population. Therefore, it is essential to carry out tests to complement this research, providing more information to the public and ensuring the safety in the use of medicinal plants.
Herbal Medicine; Synergism; Plantago major L; Punica granatum L.
