GC-MS analysis, antioxidant and antimicrobial activities of achillea odorata subsp. pectinata and ruta Montana essential oils and their potential use as food preservatives

In order to discover new natural resources with biological properties, the chemical composition, the antioxidant and antimicrobial activities, and the potential use as food preservative of essential oils of Moroccan Achillea odorata subsp. pectinata (AOpEO) and Ruta montana (RMEO) were studied. Gas chromatography-mass spectrometry (GC-MS) analysis revealed the presence of 21 and 25 compounds in AOpEO and RMEO, respectively. The results showed that the major compounds of AOpEO are camphor (45.01%), bornyl acetate (15.07%), borneol (11.33%), β-eudesmol (4.74%), camphene (3.58%), and 1.8-cineole (eucalyptol) (2.96%), whereas 2-undecanone (63.97%), camphor (3.82%) and cyclopropanecarboxylic acid (3.66%) were the main components of RMEO. The antioxidant activities were evaluated by diphenylpicrylhydraziyl radical (DPPH) and reducing power assays. The antimicrobial activities of essential oils were tested against bacterial strains and food contaminant yeast using agar disc diffiusion and microdilution methods. A significant antimicrobial activity of AOpEO was observed against Bacillus subtilis, Proteus mirabilis and Candida albicans, compared to RMEO. The efficacy of AOpEO was also evaluated in model food systems (cabbage and barley) artificially inoculated during storage. The results found that the adding of a minimal inhibitory concentration (MIC) and 4× MIC were potent in decreasing the Proteus mirabilis growth in food model systems. Our findings suggested that AOpEO may be potentially used as an alternative food preservative.