Antileishmanial potentialities of croton linearis leaf essential oil

Abstract

The essential oil was obtained from Croton linearis Jacq. leaves. Its chemical composition was analyzed by Gas Chromatography-Mass Spectrometry. A total of 82 compounds were identified, being the principal components: guaiol (7.93%); eudesma-4(15),7-dien-1β-ol (4.94%) and guaia-3,10(14)-dien-11-ol (4.52%). Antimicrobial activity was determined against six Candida spp., three bacteria (Staphylococcus aureus, Escherichia coli and Pseudomona aeruginosa) and two parasites (Leishmania amazonensis and Trypanosoma cruzi). The selectivity index (SI) was computed through the determination of it cytotoxicity on peritoneal macrophages from BALB/c mice and murine fibroblasts L929 cells. Colorimetric microdilution methods as well as direct counting in optical microscopes were performed. The essential oil showed remarkable activity against L. amazonensis (IC50Promastigote: 20.0 ± 4.9 μg/mL; IC50Amastigote: 13.8 ± 4.3 μg/mL), moderate activity against T. cruzi (IC50Trypomastigote: 197.26 ± 8.7 μg/mL) and weak activity against P. aureginosa. Cytotoxicity values were CC50= 89.1 ± 3.4 μg/mL for macrophages BALB/c and CC50= 306 ± 110 μg/mL for L929 cells, rendering a SI of 6 for amastigote form of L. amazonensis. Croton linearis Jacq. leaf essential oil, therefore, could be a potential candidate for future investigations regarding Leishmaniasis treatment.