Volatile metabolites, antioxidant and biological activities of Bursera simaruba (L.) Sarg. essential oil, from the tropical dry forest, Cesar, Colombian Caribbean Region

Abstract

Tropical Dry Forest (T-dF) is one of the most threatened ecosystems in the Neotropics, due to negative anthropogenic impacts on biodiversity and ecosystem services. Bursera simaruba (L.) Sarg. (indio desnudo, resbalamono), is among the species most reported for the T-dF of the Colombian Caribbean. In this work, the chemical composition and antioxidant and biological activities of B. simaruba essential oil (EO) were determined. EO chemical analysis from leaves and, petiole, and young branches bark (PYBB) of B. simaruba was carried out by Gas Chromatography coupled to Mass Spectrometry; polar and apolar columns were used for component separation. The biological activity of B. simaruba EO (PYBB) against Lasioderma serricorne (Coleoptera, Ptinidae) was determined by the preference area method. EO (PYBB) antioxidant capacity was determined by Oxygen Free Radical Absorbance Capacity (ORAC) assay. Reference antioxidant and standard terpenes were used for relative analysis of ORAC results. α-Terpinene (27.7% and 16.4%), p-cymene (22.8% and 44.0%), and g-terpinene (16.7% and 14.6%), were the main constituents in B. simaruba EOs (leaves and PYBB). EOs were represented by a high percentage of hydrocarbon monoterpenes (∼79.1% and ∼88.9%, leaves and PYBB); while hydrocarbon sesquiterpenes (∼3.1% and ∼4.6%, leaves and PYBB); contributed with a low percentage. B. simaruba EO (PYBB), showed attractant activity, at 0.4 μL.cm-2 (2h: -45%±7%; 4h: -50%±17%); in relation with Stay off, at 0.8 μL.cm-2, which was used as a positive control for repellent activity (2h: 66%±5%; 4h: 75%±21%). B. simaruba EO (PYBB) showed a very low antioxidant capacity (ORAC: 657.2±20.5 μmol Trolox/g sample), related to quercetin, used as reference antioxidant (50816.9±1559.1 μmol Trolox/g sample). However, EO ORAC was higher than the α-terpinene (68.0±10.8 μmol Trolox/g sample), γ-terpinene (51.2±2.0 μmol Trolox/g sample), p-cymene (105.6±6.4 μmol Trolox/g sample), used as standard terpenes. In conclusion, this is the first report on the chemical composition of the B. simaruba EO from Colombia, whose results differ from the previous ones from Jamaica and Guadeloupe. Chemical composition, reported here, with α-terpinene, γ-terpinene and p-cymene as principal compounds, could be used to establish a scientific support that explains some traditional uses. EO showed an attractive biological activity on L. serricorne. EO showed an antioxidant activity lowest quercetin (antioxidant reference), but higher that standard terpenes (α-terpinene, γ-terpinene and p-cymene).