Evaluation of an extract containing Trichoderma harzianum enzymes on cariogenic biofilm

• Grant number: 17/12379-5
• Support type: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): October 01, 2017
• Effective date (End): September 30, 2019
• Field of knowledge: Health Sciences - Pharmacy
• Principal Investigator: Carolina Patrícia Aires
• Grantee: Nayanna Gomes Silva Lacerda
• Home Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Cariogenic biofilm, rich in insoluble extracellular polysaccharides, is a determining factor for dental caries. Thus, the enzymatic degradation of these polymers may contribute to the reduction of biofilm pathogenicity and, consequently, to the control of dental caries. Thus, the objective of the present work is to evaluate the effect of an extract containing enzymes synthesized by Trichoderma harzianum in cariogenic biofilms of Streptococcus mutans. The production of enzymes by T. harzianum will be induced by the addition of S. mutans polysaccharides to the growth medium of the fungus. After 192 hours of incubation, the growth medium will be centrifuged and the supernatant containing the enzymes will be used to treat S. mutans biofilms. The biofilms of S. mutans will be formed for 5 days on glass coverslips, simulating physiological conditions of 'feast-famine' episodes that occur in the oral cavity. On the 3rd day of the experiment, the biofilms will be exposed to the following treatments (n = 3): a) NaCl 0.9%, as negative control; B) 0.1% chlorhexidine digluconate solution as a positive control; C) extract containing Trichoderma harzianum enzymes. At the end of the experimental period, the bacterial viability will be evaluated and the biofilm polysaccharides will be quantified. The experiment will be repeated 3 times. For comparison between the groups, the homogeneity and variability of the results will initially be analyzed. If the distribution of values is normal, ANOVA will be used followed by post-hoc test for comparison between groups. If the distribution is not normal, the comparison will be made using the Kruskal-Wallis test. The accepted level of significance will be 5%. (AU)