Antibacterial Activity of Calycophyllum spruceanum Leaf Extract against Enterococcus faecalis Strains “In vitro” for Endodontic Purposes

Aims: The indiscriminate use of antimicrobials contributed to the selection of multiresistant bacterial strains, mainly Enterococcus faecalis, leading to the search for new strategies for these infections, requiring the identification of new bioactive compounds from medicinal plants, an example is C. spruceanum used in traditional communities in the Amazon.

In this sense, this study aimed to evaluate the antibacterial activity of C. spruceanum leaf extract against E. faecalis "in vitro" for endodontic purposes.

Place and Duration of Study: Sample: the study was carried out at the microbiology laboratory of the Federal University of Acre (UFAC), in the city of Rio Branco, state of Acre, Brazil, from July 2021 to January 2022.

Methodology: For this study, 50mg/mL of the crude extract of C. spruceanum leaf was diluted in Dimethylsulfoxide, as well as 50mg/mL of the extract with 1000mg of calcium hydroxide and 1000mg of calcium hydroxide in 1mL of distilled water. After preparing the extracts, 20µL were deposited in the wells made on Müeler-Hinton agar medium seeded with E. faecalis, incubated for 24 hours at 37°C. After this period, the positive activity of the extracts was obtained from the formation of the inhibition halo in millimeters.

Results: The best results were for extract associated with calcium hydroxide (20mm), followed by calcium hydroxide solution (17.67mm) and with lower activity, C. spruceanum extract (14.33mm). The best results of the Minimum Inhibitory Concentration with values ​​of 6.25 mg/mL for the extract combined with calcium hydroxide and Minimum Bactericidal Concentration that was 25mg/mL for the association of the extract with calcium hydroxide.

Conclusion: The C. spruceanum extract has antibacterial activity against E. faecalis and its association with calcium hydroxide potentiated its effect.