Seleção e produção de exo e/ou polissacarídeos de origem microbiana da Amazônia para o uso em odontologia

Abstract

In recent years, importance has been given to the metabolites produced by endophytic microorganisms, due to their different biotechnological applications and the possibility of vertical transference, that is, the endophytic microorganisms are able to produce the same classes of substances from their hosts. Among the microbial polysaccharides, the main interest is focused on extracellular or exopolysaccharides, because they are biocompatible and many of them present antibiotic activity. With the objective of producing an experimental cement from exo and / or polysaccharides of microbial origin of the Amazon for the use in Dentistry and to evaluate the antimicrobial activity of its extracts against the pathogens Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Enterococcus feacalis, Candida albicans and C. tropicalis were selected and cultivated 21 lines of endophytic and aquatic fungi, whose morphological aspects indicated that they belong to the gender Trichoderma, Colletotrichum, Aspergillus, Paecilomices, Xylaria, Phomopsis and Pestalotiopsis, in potato-dextrose (BD) , plus 0.2% yeast extract at 24 ± 1 ° C for 21 to 28 days according to colon development The mycelium was separated by vacuum filtration and fixed extracellular constituents (fermented culture medium) and intracellular (mycelium) were extracted with methanol (MeOH) under refrigeration at 4°C. Assays for activity determination were performed on 96-well ELISA plates. Six groups were prepared: GC - white mineral trioxide aggregate (MTA) Angelus ® and G2 to G6 - part of the MTA powder was replaced in different concentrations (5%, 10%, 15%, 20%, 25%), by the fraction extracted from the cultivation of the fungus P. microspora. The genus Pestalotiopsis was more effective in antimicrobial tests, specifically P. microspora, an endophytic fungus obtained from the Annona sp plant of the Annonaceae family, with a minimum inhibitory concentration of 0.125 for E. feacalis, 0.25 for S. aureus, P. aeruginosa, C. albicans and 0.5 for C. tropicalis. In the evaluation of the antimicrobial activity of the experimental cement, there was activity for S. aureus, E. coli, P. aeruginosa and E. feacalis in the GC, G5 (MTA + 20%) and G6 (MTA + 25%) groups. The G6 (MTA + 25%) presented higher values of all groups and there were no significant differences between the groups of E. coli, S. aureus and E. faecalis. Chemical analyzes were also carried out from the extract. The addition of the intracellular polysaccharide extract from the endophytic fungus P. microspora improved the antimicrobial activity of the MTA and also produced an experimental membrane, constituting promising alternatives for dental use.