Toxicological assessment of a bioactive extract from Triplaris gardneriana Wedd. seeds using alternative models.

The Triplaris gardneriana Wedd. seeds extract has great therapeutic potential due to numerous biological activities such as antioxidant, antibacterial and anti-inflammatory, which are associated with phenolic content. Although this herbal preparation has shown many benefits, recently their toxicity profile has begun to be explored. In this present study, the toxic effects of T. gardneriana seeds ethanolic extract (EETg) on biological systems of different taxonomical groups and levels of complexity (from cell culture to lower vertebrates) were assessed, through a variety of viability and toxicological assays. It was found that EETg did not impair the Saccharomyces cerevisiae growth at the highest tested concentration (200 µg/mL), and no toxicant evidence was observed in Aedes aegypti larvae or in Drosophila melanogaster adult stage. Contrarily, the extract reduced the viability of undifferentiated Caco-2 cells (250 µg/mL, 40% of viable cells), but did not affect differentiated ones. The embryotoxicity in Danio rerio model showed a LC50 of 7.41 mg/L (95% confidence interval, 4.78 - 11.49 mg/L). EETg did not show signs of toxicity in the majority of the models used, but lethality and malformations in zebrafish embryos occurred. Further analyses are needed to better understand the selective toxicity mechanism of EETg on zebrafish, as well as whether the toxic effects happen in higher vertebrates.

Study of the capacity of the essential oil of Lantana montevidensis to modulate the action of fluconazole on Candida albicans and Candida tropicalis strains.

In recent decades, fungal infections have been increasing, as well as the indiscriminate use of large-scale antifungal. The objective of the present study was to characterize the chemical components of L. montevidensis leaf essential oil (EOLm) and evaluate its antifungal potential and fluconazole modulating activity against Candida strains. The essential oil was obtained by hydrodistillation and its chemical components were determined by Gas Chromatography coupled to Mass Spectrometry. The antifungal activity was determined by the microdilution method to determine the minimum inhibitory concentration. The modulatory activity of fluconazole by the oil (EOLm) was evaluated against the four Candida strains. Our results demonstrated a predominance of ß-Caryophyllene (34.96%) and Germacrene D (25.49%), while (E)-Caryophyllene (0.08%) and δ-Cadinene (0.13%) were the minor constituents. For the antifungal activity, it was evidenced that the EOLm did not inhibit the growth of Candida albicans (CA LM 77 and CA INQS 40006) and Candida tropicalis (CT INCQS 40042 and CT LM 23), but, potentiated the effect of fluconazole in particular against C. tropicalis, although the FIC index indicates indifferent modulation for all strains tested. This study strongly suggests that administration of the fluconazole in combination with plant essential oils can provide a new opportunity to improve the outcome of the drug effect.