Banca de DEFESA: BRENDA OLIVEIRA LIMA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : BRENDA OLIVEIRA LIMA
DATA : 13/10/2020
HORA: 14:00
LOCAL: Instituto Multidisciplinar em Saúde
TÍTULO:

Antimicrobial activity of the ethanolic extract, fractions and subfractions from the leaves of Schinopsis brasiliensis Engler against Streptococcus mutans UA159

PALAVRAS-CHAVES:

Caries; Streptococcus mutans; medicinal plants; Antimicrobial; Schinopsis brasiliensis Engler; biofilm, aciduric, acidogenic

PÁGINAS: 62
GRANDE ÁREA: Ciências Biológicas
ÁREA: Farmacologia
SUBÁREA: Farmacologia Geral
RESUMO:

Caries is a multifactorial and infectious oral disease that affects the majority of the world's population and for life. Streptococcus mutans is one of the main etiologic agents for the formation of dental biofilm due to its adhesion, acidogenicity and acidity, which are the main factors associated with caryogenesis. Medicinal plants can be an alternative to antimicrobial agents that allow the control of microbial biofilms. In this context, an Schinopsis brasiliensis Engler, popularly known as Brazil, has been much appreciated locally in popular medicine, due to the presence of chemical compounds that have biological activity, mainly antimicrobial. Thus, the objective of this study was to evaluate the antimicrobial activity of the ethanolic extract, fractions and subfractions of the leaves of S. brasiliensis against S. mutans UA159. For this, the tests of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum inhibitory concentration of adhesion (MICA) were performed. The activity of the ethanolic extract was evaluated in relation to inhibition of biofilm formation, its effects on glycolysis and membrane permeability to protons, and analysis of polysaccharide formation. The lowest MIC values were obtained with the ethanolic extract, dichloromethane, H3 and D4 subfractions at 31.25 μg/mL. Butanol and D4.11 did not showed MIC at the maximum concentration tested. In relation to MBC, bactericidal activity was demonstrated in the ethanolic extract, hexane, dichloromethane, ethyl acetate, H2, D2, D3, D4, D4.8 A1 and A2.  Butanol, H1, H3, H4, D4.11, D4.12, D4.13 A3 and A4 did not show MBC at the maximum concentration tested at 1000 μg/mL. The extracts tested with sub-MIC concentrations did not inhibit adherence of S. mutans UA159. In biofilm analyzes, treatment with the ethanol extract of S. brasiliensis (2 g/mL) in the tested concentration was able to reduce biomass, insoluble and alkaline soluble glucans compared to the control biofilm (p < 0.05). The S. brasiliensis leaves affected the acid production, compared to the saline group (p < 0.05). However, it did not alter the permeability of the S. mutans membrane acid tolerance (p > 0.05). This is the first report of antimicrobial activity of ethanolic extract from S. brasiliensis against Streptococcus mutans biofilm. Thus, the ethanolic extract, fractions and subfractions of the leaves of S. brasiliensis demonstrated therapeutic potential for use in preventing the formation of dental caries, as it presented antimicrobial activity and inhibited important virulence factors of S. mutans UA159. Thus, studies must be carried out to deepen the knowledge about the mechanism of action of these antimicrobials and which compounds are active against S. mutans.

MEMBROS DA BANCA:
Presidente - 1553274 - REGIANE YATSUDA
Interno - 1561874 - LUCAS MIRANDA MARQUES
Externo ao Programa - 2342538 - GUILHERME BARRETO CAMPOS