Susceptibilidade microbiana de bactérias e fungos frente ao extrato de Psidium guajara L: avaliação in vitro / Microbial susceptibility of bacteria and fungi against extracts of Psidium guajava L: in vitro evaluation

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 susceptibilityto the active ingredient could be observed. Results: The results showed that the hydroalcoholic extract wasactive against Escherichia coli (1024 ìg/ml) and Bacillus cereus (900 ìg/ml). The aqueous extract showedno antimicrobial activity. Conclusions: Despite demonstrating antimicrobial efficiency, the P. guajava extractmay be insufficient or may require a higher concentration to be fully effective.