Óleo essencial de palmarosa (Cymbopogon martinii): avaliação antimicrobiana e toxicológica

Abstract

In the past, it was discovered that plants produce a compound responsible for presenting characteristics such as smell and taste, as well as medicinal and pharmacological potential, this compound is known as essential oil (EO). EOs are volatile chemical compounds from the secondary metabolism of plants, and are present in leaves, fruits and trunks. Palmarosa (Cymbopogon martinii) is a grass belonging to the Poaceae family, and its EO has proven antimicrobial action against some bacterial and fungal strains. Most research on EOs is concentrated on a small portion of oils and the EO of Palmarosa in natura has a scarcity of studies, which arouses interest in investigating this compound, mainly due to its potential use as an active ingredient in dermocosmetics. In this sense, the antimicrobial activity of Palmarosa EO (C. martinii) was evaluated against Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 25923), Salmonella typhimurium (ATCC 13076) and yeasts Candida albicans (INCQS 40006), Candida krusei (INCQS 40147), Candida parapsilosis (INCQS 40038) and Candida glabrata (INCQS 40136) using disk diffusion and broth microdilution techniques for bacteria and yeast. Its toxicological activity was also evaluated using the Artemia salina test. In the antimicrobial evaluation using the disk diffusion technique, most microorganisms were sensitive to EO at concentrations of 175 and 87.5 mg.mL-1. The Palmarosa EO microdilution technique showed significant results for most of the microorganisms under study, with Minimum Inhibitory Concentrations (MIC) ranging from 0.68 to 2.73 mg.mL-1. Of the four bacteria S. typhimurium and the four yeasts under study, C. glabrata was the one that showed the greatest resistance to the compound. The lethality test in Artemia salina nauplii showed that in in vivo tests the Palmarosa EO has an acute toxicity since there was 100% lethality of the nauplii. The results obtained were similar to those found in the literature and were very satisfactory, thus proving the potential of the EO of palmarosa.