Antioxidant effects of the essential oils from the fruits and twigs of Juniperus excelsa subsp. excelsa on several oxidative systems

Free radicals especially reactive oxygen species damage biomolecules such as DNA, proteins, enzymes and membrane lipids. Nowadays, it is believed that antioxidant and oxidant systems play an important role in the pathogenesis of many diseases such as atherosclerosis, cancers, aging, etc. In the present study, antioxidant effects of essential oils from the fruits and twigs ofJuniperus excelsa subsp. Excelsa on several oxidative systems (red blood cells haemolysis, LDL oxidation, insulin and haemoglobin glycosylation and linoleic acid peroxidation) were studied. Plant specimens were identified after collection and essential oils from the fruits and twigs were separately extracted by steam distillation method. Three different concentration of each extracts from the fruits and twigs of plant were used. Experiments were carried out in the presence and in the absence of each concentration by Cu and spectroscopic method for LDL oxidation. 2, 2’-Azobis- (2-amidinopropane) dihydrochloride (AAPH) was used to hemolysis of red blood cells and the amount of haemolysis was measured by spectroscopic method in 540 nm. Total conjugated dienes (CDs) formation from linoleic acid was determined at the presence of FeSO in 234nm. The results of this study show that insulin and haemoglobin glycosylation were effectively inhibited by the examined essential oil, also LDL oxidation was inhibited in the presence of different concentration of these oils. Inhibitory effect of twigs on LDL oxidation was greater than vitamin C. No anti-oxidation activity on LDL oxidation was observed when the experiments run with examined-concentrations of fruit. Linoleic acid oxidation in the presence of examined-oils was efficiently inhibited and a direct correlation was observed between the level of inhibition and incubation time. The obtained essential oils inhibited red blood cells haemolysis in low concentration and accelerate red blood cells haemolysis by peroxidant properties in high concentration. These results demonstratethat the essential oils prepared from the fruit and twigs of the Juniperus excelsa subsp. excelsa possess antioxidantactivity in low concentration in several oxidative systems even them caused red blood cells haemolysis in vitro. Hence, more studies are called to examine the effect of this plant for treatment of some disease including atherosclerosis, diabetes, cancer, etc.