Chemical composition and antioxidant and antibacterial activity of Ocotea quixos

Resumen

Introduction: Ocotea quixos (Lam.) Kosterm. ex O.C. Schmidt (Lauraceae) is a plant that grows in the Colombian Amazon Region. It is used in folk medicine as sweetener, eupeptic, tranquilizer, disinfectant and local anesthetic. Its bark is used for arthritis, chronic cold and hydropsy. Its antimicrobial and antifungal activity has also been reported, as well as its properties as antiplatelet, antithrombotic and vasorelaxant agent.
Objectives: Determine the chemical composition and the antioxidant and antibacterial activity of essential oils and methanolic extracts of O. quixos leaves and stems.
Methods: Essential oils from aerial parts (leaves and stems) of O. quixos (Lam.) Kosterm. ex O.C. Schmidt (Lauraceae) were obtained by hydrodistillation and analyzed by gas chromatography / mass spectrometry (GC-MS). O. quixos methanolic extracts were subjected to phytochemical analysis. Antioxidant activity, on the other hand, was evaluated by DPPH, ABTS and FRAP, lipid peroxidation by β-carotene / linoleate bleaching, and antibacterial activity by Kirby-Bauer testing on Sensi-Disc^™ paper disks using the gram-positive and gram-negative bacteria Staphylococcus aureus and Escherichia coli, respectively.
Results: Thirty-four volatile compounds were identified, the most abundant of which was trans-methyl-isoeugenol. The stem methanolic extract had a higher phenolic content and the best antioxidant activity with 65.26 ± 0.01% inhibition in the β-carotene / linoleate bleaching test, whereas the essential leaf oil exhibited the highest inhibition values against S. aureus and E. coli.
Conclusions: The methanolic extracts were found to have greater antioxidant potential and the essential oils greater antibacterial activity, due to the presence of chemical compounds such as a-terpineol and terpinen-4-ol, terpenes characterized by their antibacterial potential.

Key words: Ocotea quixos, chemical characterization, antioxidant properties, antibacterial activity.