Phytochemical Prospection, Toxicity and Antimicrobial Activity of Mentha arvensis (Labiatae) from Northeast of Brazil

The present study has been designed with the objective to examine the ethanol extract of Mentha arvensis leaves, in order to evaluate its chemical composition, investigate its in vitro antimicrobial potential against strains of Escherichia coli, Pseudomonas aeruginosa, Shigella flexineri, Klebsiella pneumoniae and Sthaphylococcus aureus, and find its toxicity toward Artemia salina and. Phytochemical analysis revealed the presence of catechic tannins, flavones, flavonols, xantones, flavonols, flavonones and steroids. The antibacterial activity is more significant against Sthaphylococcus aureus. In toxicity tests on Artemia salina, the ethanol extract from Mentha arvensis leaves showed LC50 value of 100 mu g/mL. These results may justify the popular use of this species as it has antimicrobial activity and demonstrate its significant toxic effect on brine shrimp. However, in order to evaluate possible clinical application in therapy of infectious diseases, further studies about the safety and toxicity of isolated compounds are needed.