Cytotoxicity and anti-Sporothrix brasiliensis activity of the Origanum majorana Linn. oil

Abstract

The study aimed to evaluate the anti-Sporothrix sp. activity of the essential oil of Origanummajorana Linn. (marjoram), its chemical analysis, and its cytotoxic activity. A total of 18fungal isolates of Sporothrix brasiliensis (n: 17) from humans, dogs and cats, and a standardstrain of Sporothrix schenckii (n: 1) were tested using the broth microdilution technique (Clin-ical and Laboratory Standard Institute – CLSI M27-A3) and the results were expressed inminimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC). TheMIC50and MIC90of itraconazole against S. brasiliensis were 2 g/mL and 8 g/mL, respectively,and the MFC50and MFC90were 2 g/mL and >16 g/mL, respectively, with three S. brasilien-sis isolates resistant to antifungal. S. schenckii was sensitive at MIC of 1 g/mL and MFC of8 g/mL. For the oil of O. majorana L., all isolates were susceptible to MIC of ≤2.25–9 mg/mLand MFC of ≤2.25–18 mg/mL. The MIC50and MIC90were ≤2.25 mg/mL and 4.5 mg/mL, respec-tively, and the MFC50/90values were twice more than the MIC. Twenty-two compounds wereidentified by gas chromatography with a flame ionization detector (CG-FID) and 1,8-cineoleand 4-terpineol were the majority. Through the colorimetric (MTT) assay, the toxicity wasobserved in 70–80% of VERO cells between 0.078 and 5 mg/mL. For the first time, the studydemonstrated the satisfactory in vitro anti-Sporothrix sp. activity of marjoram oil and furtherstudies are needed to ensure its safe and effective use.