Antioxidant activity of cherry laurel fruit (Laurocerasus officinalis Roem.) and its concentrated juice

Cherry laurel fruit and its concentrated juice (pekmez) were examined for their antioxidant activities using different free-radical scavenging activity tests [hydrogen peroxide, superoxide radical, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical], together with reducing power and inhibition of oxidation of human low-density lipoprotein cholesterol. On a fresh weight basis, pekmez exhibited a significantly (P < 0.01) higher antioxidant activity than that of cherry laurel fruit in most cases. However, on a dry weight basis hydrogen peroxide and DPPH radical scavenging activities, and reducing power were significantly higher (P < 0.01) in cherry laurel fruit than in its pekmez, with some exceptions, thus indicating possible destruction of antioxidative compounds during pekmez production. This was also partly due to the moisture content of these two samples. On the basis of the results presented, it is suggested that the intake of cherry laurel fruit and pekmez rich in phenolics would have beneficial effects in improving amelioration of degenerative diseases caused by oxidative stress. Therefore, both cherry laurel fruit and pekmez might be considered as functional food ingredients and nutraceuticals.