Estudio fitoquímico de la especie vegetal Otholobium mexicanum (Trinitaria) y evaluación de su actividad biológica y antioxidante.

Abstract

Currently, the research of new molecules or compounds with therapeutic properties has gained great prominence. In this context, Ecuador stands out as a reservoir of active compounds present in its endemic flora, which have been used for many years in traditional medicine. However, they have lacked a technical-scientific basis to be recognized as potential plant species. This is the case of Trinitaria (Otholobium mexicanum). In this study, the main groups of secondary metabolites in three Trinitaria extracts (ethyl acetate D1, ethanol D2, and ethanol: water D3) were identified through phytochemical screening and thin-layer chromatography (TLC). The chromatographic profiles of Trinitaria essential oil were analyzed using gas chromatography coupled with mass spectrometry (GC-MS), characterizing compounds such as Z-dimethoxy-citral (9%), beta-pinene (7.04%), thymol (4.71%), methyl nerolate (2.43%), cis-p-mentha-2,8-dien-1-ol (24.99%), cyclocolorenone (16.13%), among others. Subsequently, the antimicrobial capacity of Trinitaria was analyzed using the bioautography and broth microdilution techniques. It showed biological activity, with MIC values of 15 µg/mL and 7.5 µg/mL in extracts D1 and D2, respectively, against Escherichia coli ATCC 6538. For Staphylococcus aureus ATCC 8739, an MIC of 30 µg/mL was reported. Additionally, an MBC of 60 µg/mL was obtained for both bacteria. Finally, the antioxidant capacity of the Trinitaria extracts was determined using the DPPH (1,1-diphenyl-2-picrylhydrazyl) method, with ascorbic acid as a control. The antioxidant capacity percentage for D1 was 58.7%, with an IC50 of 40.158 µg/mL, and for D2, the percentage was 73.9%, with an IC50 of 28.332 µg/mL. Statistical analysis was performed using multifactorial ANOVA and the LSD comparison test for both bacterial growth inhibitory activity and antioxidant capacity, showing that Trinitaria compounds present a potential source of antimicrobial and antioxidant compounds.