Prospecção fitoquímica e efeito genoprotetor das cascas da Poincianella bracteosa (TUL.) L.P. Queiroz em células meristemáticas de Allium cepa (L.)

Abstract

Poincianella bracteosa (Fabaceae), known as catingueira, is commonly used to treat diarrhea, hepatitis, infections, and migraines. This study aimed to characterize the phytochemical profile, antioxidant activity, cytotoxicity, and genoprotective effects of the ethanolic extract (EE) from the stem bark of P. bracteosa on meristematic cells of Allium cepa. Qualitative chemical prospecting and thin-layer chromatography (TLC) of the EE detected phenols, saponins, alkaloids, flavonoids, pyrogallic tannins, and terpenes, while HPLC-DAD revealed flavonoids and phenolic acids. Metabolic characterization using Orbitrap-HRMS ESI (-) of EE suggested the presence of compounds, such as kaempferol, quercetin, isoquercitrin, isovitexin, acids (ursolic, gallic, dicaffeoyl quinic, and ellagic), amentoflavone, castalagin, and corilagin, which have been evidenced for the first time in this species. EE exhibited antioxidant activity against DPPH (EC50 = 27.53 ± 0.26 μg/ml) and ABTS (EC50 = 122.81 ± 2.03 μg/ml) radicals, with a phenolic compound content of 225.53 mg EAG/g. In the A. cepa assay, EE showed cytotoxicity at the two highest concentrations (1 and 2 mg/ml), was not genotoxic at any of the concentrations (0.25, 0.5, 1, and 2 mg/ml), and demonstrated a genoprotective effect in pre-, simultaneous, and post-treatment, with percentage reduction ranging from 49.79 to 52.28 (pre), 65.17 to 93.70 (simultaneous), and 49.50 to 86.66 (post). The results showed that EE is an important source of antioxidant compounds with non-genotoxic and genoprotective effects, suggesting its therapeutic applications, especially in diseases related to oxidative stress.