Avaliação da atividade anti Pythium insidiosum de Qualea grandiflora Mart. (Vochysiaceae) e Cariniana rubra Gardner ex. Miers (Lecythidaceae)

• Ano de defesa: 2025
• Autor(a) principal: Silva, Yasmin Sena de Amorim Dias da
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Mato Grosso; Brasil; Instituto de Ciências Exatas e da Terra (ICET); UFMT CUC - Cuiabá; Programa de Pós-Graduação em Química
• Palavras-chave em Português: Qualea grandiflora; Cariniana rubra; Pitiose; Pythium insidiosum; CNPQ::CIENCIAS EXATAS E DA TERRA::QUIMICA; Pythiosis
• Link de acesso: http://ri.ufmt.br/handle/1/7495

Pithiosis, commonly known as "ferida brava" or "mal dos pântanos," is a severe disease affecting Brazilian livestock and humans, causing significant economic losses and demanding expensive treatments. This prevalent ailment in the Pantanal Mato-Grossense region is caused by the aquatic oomycete Pythium insidiosum. Infection occurs when pre-existing wounds come into contact with contaminated water or grasses containing the oomycete's motile zoospores. Given the high costs and limited efficacy of conventional treatments, the search for novel approaches, such as phytotherapy, emerges as a promising alternative. The Cerrado, the second-largest South American biome, boasts vast biodiversity, including species like Qualea grandiflora and Cariniana rubra. Q. grandiflora is traditionally used for bloody diarrhea, intestinal colic, and amebiasis, while C. rubra is employed in decoctions and infusions for inflammatory conditions, including sore throat, ovarian inflammation, and venereal diseases. Both plants have demonstrated promising antifungal results in previous biological studies against various microorganisms. This study investigated the oomyceticidal activity of crude hydroalcoholic extracts and liquid-liquid partitioned fractions from Q. grandiflora (leaves and bark) and C. rubra (bark) against Pythium insidiosum, the causative agent of pithiosis. The Minimum Inhibitory Concentration (MIC) and Minimum Oomyceticidal Concentration (MOC) of these extracts and fractions were determined in vitro to quantify their efficacy against the oomycete. Both crude extracts and the more polar fractions of Qualea grandiflora and Cariniana rubra exhibited significant oomyceticidal activity against Pythium insidiosum. Nuclear Magnetic Resonance (NMR) analyses of the active extracts and fractions revealed the presence of various classes of secondary metabolites, notably phenolic compounds, tannins, saponins, and terpenoids. These findings strongly suggest that the observed biological activity is intrinsically linked to these polar compounds. Considering the promising MIC and MOC results against Pythium insidiosum, future research can focus on developing these plant species into a new therapeutic agent, providing an alternative treatment for pithiosis, or supporting their association with currently established control methods. This offers a potential breakthrough for a disease that currently lacks a gold standard treatment.