The Composition, Antioxidant and Antibacterial Activities of Cold-Pressed and Distilled Essential Oils ofCitrus paradisiandCitrus grandis(L.) Osbeck

Abstract

The chemical composition and functional activities of cold-pressed and water distilled peel essential oils ofCitrus paradisi(C. paradisi) andCitrus grandis(L.) Osbeck (C. grandis) were investigated in present study. Yields of cold-pressed oils were much higher than those of distilled oils. Limonene was the primary ingredient of essential oils ofC. paradisi(cold 92.83%; distilled 96.06%) andC. grandis(cold 32.63%; distilled 55.74%). In addition,C. grandisoils obtained were rich in oxygenated or nitrogenated compounds which may be involved in reducing cardiovascular diseases or enhancing sleep effectiveness. The order of free radical scavenging activities of 4 citrus oils was distilledC. paradisioil > cold-pressedC. paradisioil > distilledC. grandisoil > cold-pressedC. grandisoil. Cold-pressedC. grandisoil exhibited the lowest activity in all antioxidative assays. The order of antimicrobial activities of 4 citrus oils was distilledC. grandisoil, cold-pressedC. paradisioil > distilledC. paradisioil > cold-pressedC. paradisioil. Surprisingly, distilledC. grandisoil exhibited better antimicrobial activities than distilledC. paradisioil, especially againstEscherichia coliandSalmonella entericasubsp. The results also indicated that the antimicrobial activities of essential oils may not relate to their antioxidative activities.