Chemical composition, biological activities and DNA damage protective effect of Pelargonium graveolens L’Hér. essential oils at different phenological stages

Abstract

Fresh aerial parts of Pelargonium graveolens (Geraniaceae) were collected at different phenological stages (floral budding, flowering, post flowering and vegetative) during a one-year vegetative cycle. Their oils were obtained by hydrodistillation and the yield varied from 0.14% (flowering budding stage) to 0.18% (flowering stage). Overall, 32, 29, 23 and 30 components were identified and quantified in vegetative, floral budding, full flowering and post flowering stages, representing 91.87%, 97.77%, 98.49% and 97.08%, of the oil, respectively. The antioxidant activity of P. graveolens essential oils at different stages was evaluated by the DPPH and ABTS methods. The effect against DNA damage induced by Fenton reaction was established. In fact, in the presence of essential oil and β-citronellol, a protective effect of pGEM-T was observed even with the addition of high concentration of H2O2 that caused DNA breakage by the reaction with Fe(III). Besides, the antibacterial activity of the oils and β-citronellol which represents the major compound in all samples were tested against food spoilage pathogens. Their minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were also determined. The oils collected from various phenological stages have shown high activity against all tested bacteria, thus representing an inexpensive source of natural antioxidant and antibacterial substances that reveal potential for use in pathogenic systems.