COMPOSICIÓN QUÍMICA Y ACTIVIDADES BIOLÓGICA DEL ACEITE ESENCIAL DE MARGYRICARPUS PINNATUS (LAM.) KUNTZE

Abstract

Margyricarpus pinnatus (Lam.) Kuntze, commonly name nigua or piquiyuyo in Ecuador, is a subshrub and grows primarily in the montane tropical biome. The chemical composition, antioxidant and antimicrobial activities of its essential oil from the leaves and flowers of plants grown in the Ecuadorian Andes were studied. The essential oil was obtained by hydrodistillation with a yield of 0.36 % v/m. With the aid of gas chromatography with mass and flame ionization detectors (GC-MS and GC-FID), 134 volatile constituents making up 97.5 % of the total oil constituents were identified. The major groups of compounds were aromatic compounds (51.9 %), oxygenated monoterpenes (16.3 %) and monoterpene hydrocarbons (12.5 %). The most abundant compounds were carvacrol (23.1%) and carvacryl acetate (19.2 %). Antioxidant activity was examined using DPPH and ABTS assays. The essential oil had a high scavenging effect and reduction of ferric ion capacity through FRAP assay. The results show that the essential oil scavenged DPPH∙ radical and ABTS·⁺ radical capacity as reflected by the IC₅₀ values 1.18 ± 0.27 mg/mL and 4.47 ± 0.31mg/mL, respectively. These results agreed with the literature for essential oils that phenols possess high antioxidant activity. The antimicrobial activity was determined against four pathogenic bacterial strains and a pathogenic fungus strain using a modified agar-diffusion method. The results of the antimicrobial tests showed that Escherichia coli and Candida albicans were very sensitive to the effects of the essential oil