Thornton, Maria das Graças AlmeidaLopes, Tiago Felipe de Senes2023-09-152023-09-152023-07-21LOPES, Tiago Felipe de Senes. Caracterização química, avaliação toxicológica e aspectos préclínicos associados ao efeito protetor do extrato hidroalcoólico das cascas de Pseudobombax parvifolium (Malvaceae) sobre o estresse oxidativo. Orientador: Maria das Graças Almeida. 2023. 63f. Tese (Doutorado em Ciências da Saúde) - Centro de Ciências da Saúde, Universidade Federal do Rio Grande do Norte, Natal, 2023.https://repositorio.ufrn.br/handle/123456789/54857Brazil's plant biodiversity offers a rich source of bioactive compounds with phytotherapeutic potential. In this context, the embiratanha (Pseudobombax parvifolium) an endemic species of the Caatinga recognized for its traditional use, particularly in cases of inflammatory processes linked to cellular oxidative stress. Although the biological and toxicological properties of this plant have been little explored, this research stands out for being a pioneer in characterizing its chemical composition, quantifying the contents of phenolic compounds and flavonoids, and analyzing its toxicological and mutagenic profile for the hydroalcoholic extract of embiratanha bark (EBHE). The results reveal a yield of 8.92%, also showing a high concentration of polyphenols. The total content of phenolic compounds reaches 24.26 mg GAE/g dry EBHE, while the amount of flavonoids reaches 16.84 mg QE/g dry EBHE. Phytocomponents such as catechin 7-arabinofuranoside, glycoside and loliolide were identified by LC-MS/MS analysis, the latter being identified for the first time in this species. Toxicity tests with cell lines (3T3, HEK293, VERO and BRL-3A) and Wistar rats showed that EBHE does not have toxic effects, and no signs of mutagenicity were observed in Drosophila melanogaster. With regard to oxidative stress, EBHE showed a reduction of about 50% in lipid peroxidation at doses of 2000 mg/kg (acute oral toxicity) and 100, 200 and 400 mg/kg (repeated dose toxicity). Despite the absence of changes in glutathione (GSH) levels in any of the assays, there was a significant increase in superoxide dismutase (SOD) activity at a dose of 400 mg/kg and in glutathione peroxidase (GPx) at doses of 100, 200 and 400 mg/kg, especially in the repeated dose test. This suggests a possible induction of SOD and GPx enzymes, reinforcing cell protection. In summary, the levels of EBHE tested did not demonstrate adverse effects, whether in in vitro or in vivo experiments, in acute or repeated dose exposures. Furthermore, the absence of mutagenicity confirms the viability of the traditional use of embiratanha. This highlights the importance of quality control to assess the safety, efficacy and validity of using medicinal plants, considering possible risks related to their chemical composition.Acesso AbertoMalvaceae (Pseudobombax parvifolium)Bioma caatingaEstresse oxidativoMedicina tradicionaldoctoralThesisCNPQ::CIENCIAS DA SAUDE