Abstract

SILVA, Rafael Menezes et al. Microbial susceptibility of bacteria and fungi against extracts of Psidium guajava L.: in vitro evaluation. Arq. Odontol. [online]. 2013, vol.49, n.2, pp. 60-65. ISSN 1516-0939.

Aim: The present study aimed to evaluate the in vitro antimicrobial activity of hydroalcoholic and aqueous extracts from leaves of P. guajava on four bacterial and two fungal samples to determine the range of minimum inhibitory concentration of the extracts. Material and Methods: The antimicrobial activity of extracts of different polarities was compared using the agar dilution method. Differences in susceptibility to the active ingredient could be observed. Results: The results showed that the hydroalcoholic extract was active against Escherichia coli (1024 μg/ml) and Bacillus cereus (900 μg/ml). The aqueous extract showed no antimicrobial activity. Conclusions: Despite demonstrating antimicrobial efficiency, the P. guajava extract may be insufficient or may require a higher concentration to be fully effective.

Keywords : Psidium; Products with antimicrobial action; Traditional medicine.