Antioxidant and Antiproliferative Activity of the Ethanolic Extract of Equisetum myriochaetum and Molecular Docking of Its Main Metabolites (Apigenin, Kaempferol, and Quercetin) on β-Tubulin

Abstract

<i>Equisetum myriochaetum</i> is a semi-aquatic plant found on riverbanks that is commonly used in traditional medicine as a diuretic agent. Additionally, the genus <i>Equisetum</i> stands out for its content of the flavonoid kaempferol, a well-known antiproliferative agent. Therefore, in this study, <i>E. myriochaetum</i> ethanolic extract was tested in vitro against a cervical cancer cell line (SiHa). Additionally, the antioxidative activity was evaluated through a 2,2-diphenyl-1-picrilhidrazil (DPPH) assay. Finally, a molecular docking analysis of apigenin, kaempferol, and quercetin on the active site of β-tubulin was performed to investigate their potential mechanism of action. All fractions of <i>E. myriochaetum</i> ethanolic extract showed antioxidative activity. Fraction 14 displayed an antiproliferative capacity with a half maximal inhibitory concentration (IC₅₀) value of 6.78 μg/mL against SiHa cells.