Essential oil of Algerian rose-scented geranium (Pelargonium graveolens): Chemical composition and antimicrobial activity against food spoilage pathogens

The aim of this study was to analyse the chemical composition of essential oil of rose-scented geranium (Pelargonium graveolens L) growing in Algeria and to test the efficacy of the oil against food spoilage and food-borne pathogens. The chemical composition of the oil was analysed by Gas Chromatography-Mass Spectrometry (GC -MS). A total of 45 compounds representing 94.2% of the essential oil were identified. The main constituents were citronellol (30.2%), citronellyl formate (9.3%) and geraniol (7.6%). The antimicrobial activity of essential oil was evaluated against 23 food spoilage microorganisms in liquid and vapour phase at three different concentrations (10, 20 and 30 mu l/disc). The oil exhibited promising antibacterial effect against Gram positive more than Gram negative bacteria and provides a good inhibitory effect against Candida strains. Furthermore, the zone of inhibition increased with increasing oil concentration. Significantly higher antimicrobial activity was observed in the vapour phase. This is the first report on the antimicrobial properties of the essential oil of Algerian rose geranium. Our results suggest that rose-scented geranium oil could be used for the development of novel types of antibacterial agents to control food spoilage and food-borne pathogens. (C) 2013 Elsevier Ltd. All rights reserved.