Identificação de substâncias majoritárias presentes na Equisetum hyemale e avaliação das atividades antimicrobiana, antibiofilme, cito e genotóxicas

• Ano de defesa: 2020
• Autor(a) principal: Alves, Camilla Filippi dos Santos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Santa Maria; Brasil; Análises Clínicas e Toxicológicas; UFSM; Programa de Pós-Graduação em Ciências Farmacêuticas; Centro de Ciências da Saúde
• Palavras-chave em Português: Atividade antimicrobiana; Biofilme; Plantas; Compostos fenólicos; Antimicrobial activity; Biofilm; Plants; Phenolic compounds; CNPQ::CIENCIAS DA SAUDE::FARMACIA
• Link de acesso: http://repositorio.ufsm.br/handle/1/21030

Biofilms are clusters of microbial cells, adhered to a surface and protected by layers of extracellular polymeric substances (SPE). A large proportion of infections related to the use of implants and medical devices are associated with the formation of these biofilms. Accepting the complex biofilm architecture, control and treatment is complex and difficult. The formation of biofilm follows successive stages, obeying determining conditions (microbial motility, self and co-aggregation and quorum sensing (QS) signaling). For this reason, it is important to look for alternatives that can interfere in these steps and, in some way, inhibit the formation of biofilms. In this case, this study used Equisetum hyemale, popularly known as Horsetail, a typical plant of temperate climate that is widely used in folk medicine as a diuretic and digestive. This study aimed to identify the main substances present in E.hyemale, to evaluate antimicrobial activities, antibiofilm, anti-QS, citations and genotoxic. An antibacterial activity was evaluated by the microdilution method against a broth of P. aeruginosa 01. The cytology and genotoxicity tests were performed by the MTT test and the Comet test, respectively. Biofilm inhibition was evaluated in polystyrene plates using the violet crystal technique and also with Atomic Force Microscopy (AFM). Factors essential to the biofilm's physiology, such as motility (swimming, swarming and twitching), were analyzed in the presence and absence of extracts and isolated substances. Inhibition of quorum sensing was observed using the Chromobacterium violaceum pattern. The extracts and phenolic compounds used were able to inhibit biofilm formation and interfere with important crucial factors. In addition, the production of violacein (QS product in Chromobacterium violaceum) was inhibited, suggesting that crude extract, fractions and major compounds of E. hyemale exhibit important antibiofilm and anti-QS activity. E. Hyemale therefore appears as a promising way to reduce microbial adhesion on surfaces, since we have not observed the mentioned toxic and genotoxic effects on mononuclear blood cells.