Chemometrics Evaluation of Lemongrass Essential Oils: Authenticity, Quality and Selection Of Bioactives against t. cruzi.

Abstract

The effectiveness of treatments against the parasite Trypanosoma cruzi, the causative agent of Chagas disease, is limited in the chronic phase of the disease. The essential oils of lemongrass (Cymbopogon citratus and Cymbopogon flexuosus) have shown activity against this parasite. This study aimed to use principal component analysis (PCA) to analyze the data of lemongrass essential oils submitted to gas chromatography with flame ionization detector (GC-FID) and proton nuclear magnetic resonance (1H NMR) as well as partial least squares (PLS) regressions to correlate chemical variability with the results of biological assays. The PLS models highlighted geraniol, caryophyllene, and limonene as the main compounds responsible for antioxidant activity. Regarding cytotoxicity, the PLS models indicated that this activity is a cumulative effect of multiple compounds. For the trypanocidal effect, median lethal concentration (CL50) values ranged from 15.12 ± 3.96 to 110.10 ± 11.22 μg mL−1, resulting in selectivity index (SI) values of 2.99 to 22.55 times more selective for T. cruzi compared to host cells. PLS indicated that geraniol, neral and geranial were the main contributors to the trypanocidal effect, suggesting the potential for somatic or synergistic effects against trypomastigote forms.