Ramazan Erenler and Nuray Senturk
Department of Chemistry, Faculty of Art and Science, Gaziosmanpasa University, Tokat, Turkey
Rhododendron belonging to the Ericaceae family composed of nearly 1000 species distributed throughout the world. Among them, over 800 species are distributed throughout the Northern Hemisphere. There are five Rhododendron species in Turkey and Rhododendron luteum grows up in Black Sea region . Rhododendron speices consists of bioactive secondary metabolites [2, 3]. In this work, plant material was collected from Ordu, Turkey and dried at shade. Antioxidant activity of essential oil as well as methanol extract of flowers were presented. The essential oils of flowers were carried out by steam distillation using neoclevenger apparatus. The antioxidant activity of methanol extract and essential oils were carried out using different antioxidant assays, including DPPH free radical scavenging, ABTS cation radical scavenging activities. BHT and α-tokoferol were used as reference antioxidants. The essential oil exhibited moderately DPPH free radical scavenging activity. However, methanol extract revealed strong both DPPH free radical scavenging activity and ABTS cation radical scavenging activity. The chemical compositions of essential oil from the flowers were determined by GC-MS analysis which allowed identification of 30 components, the main ones are caryophyllene (35.2%) and veridiflorol (7.54%).
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