Evaluation of protocols for the extraction of intracellular polysaccharides from cariogenic bacteria

• Grant number: 18/14113-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2018
• End date: October 31, 2019
• Field of knowledge: Health Sciences - Dentistry
• Principal Investigator: Carolina Patrícia Aires Garbellini
• Grantee: Bruna Pereira Penachin
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Considering that bacterial intracellular polysaccharides (IPS) may be an important factor for the development of dental caries with associated methodological limitations in their extraction, the objective of the study is to evaluate the effect of different extraction protocols on streptococcus mutans IPS. Thus, biofilms of S. mutans UA 159 will be formed for 5 days on glass slide placed in culture medium supplemented with 1 % sucrose, with the goal of simulating physiological conditions for dental biofilm formation in the oral cavity. After growth, the biofilms will be collected and the matrix polysaccharides will be extracted from where IPS will subsequently be extracted. This extraction advocates the lysis of bacterial cell wall in the presence of high temperature and a strong base. Thus, the samples will be subjected to one of the following extraction modes: 1) 1 M NaOH at 100 ºC for 5 min; 2) 1 M NaOH at 100 ºC for 10 min; 3) 1 M NaOH at 100 ºC for 15 min; 4) 0.5 M NaOH at 100 ºC for 5 min; 5) 0.5 M NaOH at 100 ºC for 10 min or 6) 0.5 M NaOH at 100 ºC for 15 min. After precipitation with ethanol, the polysaccharides will be quantified by spectrophotometry and analyzed in terms of their monosaccharide composition. For the purposes of comparison between groups, the normality of residues and homogeneity of variances will be applied. If the values are normal, the ANOVA will be used, followed by a Tukey's post-hoc test for comparison between groups. If it is not normal, a comparison will be made using the Kruskal-Wallis' test. The accepted level of significance will be 5%.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

ARAGON-LEON, ALEJANDRA; MORENO-VILET, LORENA; GONZALEZ-AVILA, MARISELA; MONDRAGON-CORTEZ, PEDRO MARTIN; SASSAKI, GUILHERME LANZI; MARTINEZ-PEREZ, RAUL BALAM; CAMACHO-RUIZ, ROSA MARIA. Inulin from halophilic archaeon Haloarcula: Production, chemical characterization, biological, and technological properties. Carbohydrate Polymers, v. 321, p. 11-pg., 2023-12-01. (18/14113-5, 16/24042-2)