COMPARATIVE STUDY OF THE ESSENTIAL OILS OF TWO ACINOS SPECIES: CHEMICAL COMPOSITION AND ANTIMICROBIAL ACTIVITY

GC and GC/MS analyses of the essential oils obtained from the aerial parts of Acinos suaveolens and Acinos majoranifolius were performed. Fifty-six constituents, accounting for 95.11% of Acinos suaveolens essential oil, were identified. The main compound was pulegone (48.47%), while caryophyllene oxide (7.14%), isomenthone (4.37%) and spathulenol (4.12%) were detected in a considerably lower percentage. Thirty-five compounds comprising 99.80% of the Acinos majoranifolius essential oil were recognized. The essential oil was characterized by pulegone (82.07%) as the major constituent. Also, isomenthone (9.73%), transisopulegone (1.12%) and b-cariophyllene (1.03%) had a significant percentage. Other components are presented with less than 1%. A disk diffusion method was used for the assessment of the antimicrobial activities of the essential oils against microorganisms (bacteria: Bacillus subtilis, Sarcina lutea, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Salmonella enteritidis and Escherichia coli; fungi: Aspergillus niger, Candida albicans and Saccharomyces cerevisiae). The preliminary bioassay results indicated that the essential oils of Acinos suaveolens and Acinos majoranifolius could be possible sources of compounds with valuable antimicrobial activity.