Chemical analysis of Moringa oleifera (Moringaceae) seed oil and potentiation of antibiotic activity against standard and multidrug-resistant bacterial strains

•M. oleifera did not demonstrate intrinsic antibacterial activity.•M. oleifera showed synergistic effects through the reduction of MICs for antibiotics.•The chemical analysis of the oil showed the dominance of oleic acid.•The docking analysis showed a low binding energies with the non-penicillin site.•This point can explain the reduction of MICs for antibiotics. Moringa oleifera (“moringa”) seeds are sources of fixed oil with a composition of fatty acids important for their biological properties. This work aimed to verify the fixed oil of seed, regarding chemical composition, antibacterial activity alone and in association with antibiotics against standard and multidrug resistant bacterial strains. In the chemical composition of the fixed oil, the unsaturated fatty acids (78.26 %) predominated in relation to saturated fatty acids (17.34 %). The palmitic acid (5.88 %), behenic acid (4.27 %), stearic acid (4.17 %) and oleic acid (74.15 %) were the main constituents. Physicalchemical analyzes for moisture, acidity, pH, relative density, peroxide index and refractive index indicated chemical quality of the oil. We performed docking calculation to prioritize low affinity major molecules present in the chemical composition. The docking result of the all compounds showed that highest binding energy type Hydrogen bond, water hydrogen bond and hydrophobic interaction. The fixed oil did not show antibacterial activity alone with a minimum inhibitory concentration (MIC ≥ 1024 μg/mL) for the analyzed bacterial strains. Synergistic effects were verified in the association of the fixed oil with gentamicin, ofloxacin and penicillin against multiresistant strains, with reductions in MICs.