Desenvolvimento e validação de metodologia analítica por CLAE e atividade antibacteriana do extrato de Mikania glomerata Sprengel e do seu metabólito ácido caurenóico frente à bactérias cariogênicas

Abstract

The Mikania glomerata, given its importance and popular use is among the various plants mentioned in the List of Simplified Registration Herbal Medicines, published by the National Health Surveillance Agency. Known as guaco in phytochemicals terms, this species is characterized especially by the presence of coumarin, sesquiterpenes, diterpenes of kaurano type, ο-coumaric acid, o-hydroxycinnamic acid and syringaldehyde. Among the diterpenes identified in this plant species is the kaurenoic acid which is attracting a lot of interest in relation to its antibacterial activity. In order to exploit this potential antibacterial, this study aimed to make activity antibacterial evaluation studies of M. glomerata fraction and kaurenoic acid against the main cariogenic bacteria. The objective also isolate, identify and quantify the kaurenoic acid in M. glomerata fraction, and to develop and validate an analytical methodology. The results obtained, M. glomerata prepared fraction resulted in a standardized fraction rich in diterpene kaurenoic acid. Analytical studies were used to determine a validated method to determine the kaurenoic acid content in M. glomerata fraction, suiting the growing demand for quality and safety. Promising results have been demonstrated of Minimum Inhibitory Concentration (MIC) of 6.25 µg/mL for fraction and kaurenoic acid against all major cariogenic bacteria tested, except for Enterococcus faecalis and bacteriostatic effect (Minimum Bactericidal Concentration - CBM 12.5 µg/mL) against Streptococcus mutans, Streptococcus mitis, Streptococcus sanguinis and Lactobacillus casei. In kinetic bactericidal assay, the samples showed bactericidal action against S. mutans concentrations (12.5, 25.0 and 37.5 µg/mL), 6 h of incubation, demonstrating a significant reduction in the number of microorganisms within the first 30 min. The evaluation of the inhibition of biofilm formation by S. mutans by samples were inhibitory concentration values Minimum of Biofilm (CIMB50) promising, especially the activity of the fraction at a concentration of 1.56 µg/mL. From the results, it can be concluded that M. glomerata fraction rich in kaurenoic acid can be considered a promising compound for use in odontology since one has analytical methodology standardization validated and in vitro antibacterial activity against major cariogenic bacteria.