Resumo

GARCIA-VAZQUEZ, L. M. et al. Antioxidant and antibacterial effect of different extracts from Tithonia tubaeformis.. Revista bio ciencias [online]. 2023, vol.10, e1348.  Epub 22-Fev-2024. ISSN 2007-3380.  https://doi.org/10.15741/revbio.10.e1348.

The genus Tithonia has been extensively studied to determine its bioactive effects of pharmaceutical and nutritional interest; therefore, this study aimed to determine the antioxidant and antibacterial effect of five extracts of Tithonia tubaeformis, obtained with ascending polarity solvents, hexane, dichloromethane, ethyl acetate, methanol, and ethanol. In addition, tannins, alkaloids, and total phenols were identified. The antioxidant effect of ABTS, DPPH radicals, and ferric ion reducing power was measured, and the Minimum Inhibitory Concentration of each extract was determined on Escherichia coli, Salmonella typhimurium, Salmonella enteritidis, and Listeria monocytogenes. The results showed that the five extracts have antioxidant effects on ABTS, DPPH radicals, and ferric ion-reducing potential; however, methanol and ethanol had a statistically significant effect (p < 0.05). In addition, methanol, ethanol, and ethyl acetate extracts showed antimicrobial activity; ethanol solvent was the best, with a Minimum Inhibitory Concentration of 1 mg/mL on Escherichia coli and 3 mg/mL on Salmonella typhimurium, Salmonella enteritidis, Escherichia coli, and Listeria monocytogenes respectively. These results suggest that Tithonia tubaeformis may be of pharmaceutical and nutritional interest due to the bioactive effects of phytochemicals in its extracts.

Palavras-chave : DPPH; Ferric ion; Pathogenic bacteria.