The association between drugs and herbal products: In vitro enhancement of the antibiotic activity by extracts of dry floral buttons of Egletes viscosa L. (macela)

IntroductionEgletes viscosa L., also known as chamomile, is commonly used in traditional medicine as a tea for the treatment of digestive disorders and also inflammatory problems. The aim was to evaluate and compare in vitro the antibacterial activity of hexane and methanolic extracts of dried flowers of E. viscosa against standard strains of multiresistant bacteria, as well as determine the antibiotic-modifying activity of the extracts and identifying their secondary metabolites.MethodologyHexane and methanolic crude extracts of the flowers of E. viscosa were assessed for antibacterial activity by the microdilution test to determine the minimum inhibitory concentration (MIC) and modulation of aminoglycoside (amikacin and gentamicin) activity.ResultsMIC against bacteria was ≥1024 μg/mL for both the methanolic and hexane extracts of E. viscosa. The results showed that the combination of methanolic extract with gentamicin or amikacin demonstrated significant synergism against all strains tested (p < 0.001), while the combination of the hexane extract with the antibiotics showed significant synergism only against Pseudomonas aeruginosa 03.ConclusionThe results suggest that E. viscosa L. may be a promising compound for combating bacterial resistance. The combination of natural products with aminoglycosides may be an alternative to minimize the undesirable effects of antibiotics.