Isolation and characterization of Lactobacillus spp. from oral cavity and its prob...
| Grant number: | 17/15529-8 |
| Support type: | Scholarships in Brazil - Master |
| Effective date (Start): | March 01, 2018 |
| Effective date (End): | August 31, 2018 |
| Field of knowledge: | Health Sciences - Dentistry |
| Cooperation agreement: | Coordination of Improvement of Higher Education Personnel (CAPES) |
| Principal Investigator: | Juliana Campos Junqueira |
| Grantee: | Janaina Araújo de Alvarenga |
| Home Institution: | Instituto de Ciência e Tecnologia (ICT). Universidade Estadual Paulista (UNESP). Campus de São José dos Campos. São José dos Campos , SP, Brazil |
Abstract The probiotics use as a prevention method for dental caries has been extensively investigated with promising results. Therefore, it is necessary to develop formulations for application to the oral cavity containing probiotic strains with activity against Streptococcus mutans. Therefore, this project aim will be to evaluate the antimicrobial effects of 3 probiotic formulations containing Lactobacillus paracasei 28.4, which are being developed by our research group, on the polysaccharides production and S. mutans biofilms formation. Firstly, the formulations will be tested on 10 S. mutans clinical strains isolated from patients with active caries lesions in relation to their effects on the polysaccharide production capacity by the sulfuric-anthrone method. Subsequently, 3 isolates of S. mutans, with lower production of polysaccharides by the application of the probiotic formulation, will be selected for the biofilms study. The antimicrobial effect of probiotic formulations will be evaluated, prophylactically and therapeutically, on S. mutans biofilms formed at the times of 1, 4 and 8 h on saliva coated hydroxyapatite discs. The biofilms formed will be analyzed by quantifying the total biomass by violet crystal absorbance, viable cell counting (Colony Forming Units / CFU/mL) and scanning electron microscopy. In order to elucidate the action mechanisms involved in the effects of probiotic formulations on S. mutans, we will also perform the quantification of genes related to the enzymes glycosyltransferases B, C and D production, involved in the production of glucans that promote adherence and accumulation of S. mutans on the dental surface. The quantification of the gene expression will be done by real time PCR. The data obtained in each test will be submitted to an exploratory analysis for the selection of the most suitable statistical test for each experiment. In all tests will be used the program GraphPad Prism 5.0, considering a level of significance of 5%. (AU) | |