Caracterização Química e efeito citotóxico do extrato hidroetanólico das partes aéreas de Scoparia dulcis (Plantaginaceae)

Abstract

Cancer, a leading cause of global mortality, presents challenges to conventional treatments such as chemotherapy due to low selectivity and tumor resistance to treatment. In this scenario, Brazilian biodiversity, rich in plant species with bioactive properties, emerges as a promising source for the discovery of new drugs. Therefore, this study aimed to investigate the chemical composition and biopharmacological potential of Scoparia dulcis. The chemical annotation of S. dulcisleaf extract (EFSD) by Liquid Chromatography coupled with Mass Spectrometry (LCMS), revealed a wide variety of compounds, including flavonoids, terpenoids and phenolic acids, recognized for their anti-inflammatory, antioxidant, antidiabetic and antiproliferative activities. In addition, the extract was subjected to a separation process, where it was possible to isolate two compounds, VAMF-1 (flavonoid extracted from the broom with methanol - cirsimarin). To confirm the identity of VAMF-1, hydrogen (1H) and carbon (13C) nuclear magnetic resonance spectroscopies provided the characteristic signals, validating its chemical structure as a methoxylated, glycosylated flavonoid. In the evaluation of the antioxidant potential, by the DPPH method, the concentrations of 62.5 and 125 μg mL-1 , respectively, demonstrated the ability of the antioxidant present in EFSD to neutralize free radicals, evidenced by the reduction of DPPH. The cell viability of EFSD, VAMF-1 and VAMF-2 was evaluated in the MCF-7 (derived from metastatic human breast adenocarcinoma) and T24 (derived from grade III transitional bladder urothelial cell carcinoma) cell lines in two-dimensional models and only EFSD and VAMF-1 were analyzed in three-dimensional models. Regarding EFSD, an inhibition of cell viability was observed from the concentration of 100 μg mL-1 . For MCF-7 cells, the inhibitory concentration was 100.1 μg mL-1 after 24 hours of treatment. When compared with T24 cells, EFSD showed an inhibitory concentration of 129.4 μg mL-1 , showing a higher resistance compared to MCF-7. EFSD was active against the MCF-7 lineage, however, for T24 cells it was not active, with an inhibitory concentration (IC50) of 129.4 μg mL-1 , being higher than 100 μm mL-1 (maximum concentration for an extract to be considered active). In the toxicity test on Tenebrio molitor larvae, the least cytotoxic concentration was 100 μg mL⁻¹. In addition to annotating the secondary metabolites, the study evaluated the antitumor activity of the isolated compounds, reinforcing their potential as promising candidates for the development of new drugs.