Antibacterial effect of isoeugenol against Pseudomonas aeruginosa

Abatsract Pseudomonas aeruginosa is an important nosocomial pathogen and its clinical importance is mainly related to nosocomial infections. Increased rates of bacterial resistance in recent years has led WHO to publish a global priority list to guide research and discovery of new antibiotics, where P. aeruginosa is among the group of bacteria for which there is a critical level of priority for new drugs to be discovered. In this context, isoeugenol appears as an interesting alternative and the objective of this study was to investigate its action against P. aeruginosa. Isoeugenol presented significant antibacterial activity, with minimum inhibitory concentration (MIC) of 64µg/mL and minimum bactericidal concentration (MBC) of 128µg/mL, and was considered bactericidal against this species. Molecular docking revealed interactions that suggest that isoeugenol may bind to the enzyme Penicillin-Binding Protein 3 and interfere with the bacterial cell wall synthesis process. This study reinforces the antibacterial potential of this compound and emphasizes that more studies are needed in order to better investigate its mechanism of antibacterial action.

Antifungal action of α-pinene against Candida spp. isolated from patients with otomycosis and effects of its association with boric acid.

The genus Candida is one of the main causes of otomycosis. The growing index of fungal strains resistant to antifungals makes necessary the search for new agents and α-pinene is a phytoconstituent present in plants with remarkable antimicrobial activity, which becomes an interesting object of study. Thus, the objective of this research was to evaluate the antifungal activity of α-pinene against Candida species isolated from otomycosis, determining the Minimum Inhibitory and Fungicide Concentrations, micromorphological analysis and verifying the effects of the association with boric acid. α-pinene showed significant antifungal activity, with greater inhibitory activity against C. parapsilosis, fungicidal action and proved to be effective in inhibiting fungal structures, such as pseudo-hyphae and promoting a marked decrease in blastoconidia. The combination of α-pinene with boric acid produced additive effects that may be interesting for use in clinical practice.