Avaliação da atividade antimicrobiana da Annona crassiflora mart. frente a microrganismos da microflora endodôntica

Abstract

The aim of the study was to evaluate the antimicrobial activity of the etanolic extract of the Annona crassiflora Mart., against the microrganisms of the endodontic microflora, aerobic, Enterococcus faecalis, Pseudomonas aeruginosa, fungi, Candida albicans and anaerobes, Prevotela melanogenicus, Clostridium sp., and Bacteroides fragilis. The methodology used involved the preparation of the etanolic extract, the liquid-liquid parttion and cromatographic purification using G 60 silica gel, silica gel with 10% of KOH and activated silica gel and LH-20 Sephadex. Procedure of purification was followed by antimicrobial activity bioassay. The identification of chemical compounds from the active fractions of the A. crassiflora were made using the espectroscopic method of magnetic resonance of 1H and 13C. The antimicrobial assay activity, for the aerobic microrganisms, E. faecalis, P. aeruginosa and fungi, C. albicans the diffusion method in disc was used. For the anaerobic microrganisms P. melanogenicus, Costridium sp., and B. fragillis the the diffusion method in broth tioglicolato was used. Also the minimun inibitory concentration (MIC) of the active fractions from the wood, bark and stem extracts of the A. crassiflora were determined and compare with the minimum inibitory concentratioon (MIC) of the standards drugs (Fluconazol, Ofloxacin, Metronidazole) and Calcium Hidroxyde used in this study. The antimicrobial evaluation tests demonstrated that the fractions of bark and wood ethanolic extracts the A. crassiflora Mart., did not present antimicrobial activity against the E. faecalis, however, presented positive activity but presented antimicrobial activity against the P. aeruginosa and the C. albicans. This study also demonstrated that the bark and stem fractions of the ethanolic extracts of the Annona crassiflora Mart., presented antimicrobial activity against the P melanogenicus, Clostridium sp., and B. fragilis, however bigger expectrum antimicrobial activity was for the Clostridium sp. Of the active fractions of the extract of the A.crassiflora Mart., A6, A10, A11 and A13 were gotten the acetogenin Goniodonin that presented in the samples A11 and A13 a CIM=1000μg/mL for C. albicans and Clostridium sp, CIM=2000μg/mL for P. aeruginosa and B. fragilis and CIM>2000μg/mL for P. melanogeniccus while in the samples A6 and A10 μg/mL for C presented a CIM=2000. albicans, P. aeruginosa and B. fragilis, CIM>2000μg/mL para P. melanogenica and CIM=62μg/mL. The samples A3, A7 and A12 had presented one expectro of similar RMN of the acetogenins without the presence of the lactônico ring and had demonstrated the same antimicrobiana activity for the P.aeruginosa, C. albicans, B. fragilis (MIC=2000μg/mL) and P. melanogeniccus (MIC>2000 μg/mL) while for the Clostidium sp the samples A3 and A7 had presented a MIC=62 μg/mL while a sample A12 had presented a MIC=500 μg/mL).