Bioguided Assay of Polyphenols Isolated from Medicinal Mayan Species and its Activity Against Leishmania mexicana.

Abstract

Objective: This study underlines the in vitro leishmanicidal activity of the methanol extracts (MeOH), fractions of n-hexane (n-Hex), chloroform (TCM) and ethyl acetate (EtOAc), and compounds isolated from plant species used in the Mayan traditional medicine. Materials and Methods: Extracts of medicinal species collected in the Mayan Peninsula such as Hylocerus undatus, Bauhinia divaricate, Euphorbia hirta, Ruellia nudiflora and Cedrela odorata, were tasted in a bio guided assays against amastigotes of Leishmania mexicana. Different chromatographic techniques were applied in order to isolated the most active compounds. Additionally, spectroscopic experiments 1 H-NMR, 13C-NMR, LC-MS and FT-IR were stablished to determine the chemical structure of the chemical compounds. Results: Euphorbia hirta and Cedrella odorata, showed good bioactivity with 14.81 ± 2.63 g/mL and IC50 = 18.39 ± 0.88 µg/mL respectively, meanwhile Bauhinia divaricata not show activity and Ruellia nudiflora showed poor activity with IC50 = 92.18 ± 3.64 µg/mL, followed by Hylocerus undatus with IC50 = 122.5 ± 20.99 µg/mL, when tasted against amastigotes of Leishmania mexicana. Spectroscopic data confirmed the presence of quercetin, myricetin, kempherol and scopoletin, with IC50 = 2.92 ± 0.42 µM, 12.30 ± 0.57 µM, 20.22 ± 4.66 µM and 4.05 ± 0.68 µM respectively. Conclusion: The bioguided assays guided us, to the purification and isolation of four different metabolites, mainly flavonoids and structurally related compounds, some of them show good activity, however, their low bioavailability indicates the need for detailed structural relation activity studies, together with the development of formulations and delivery systems.