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.