Viability of lymphocytes was determined by Trypan Blue test. For the evaluation of the antioxidant activity, total phenol and flavonoid contents and 2,2-diphenyl-1-picrylhydrazyl (DPPH) inhibitory activity of the extract were determined. DNA damage was determined by alkaline comet assay in human peripheral blood lymphocytes.
Lymphocytes exhibited >86 % survival up till the concentration of 800 μg/ml of the extract. Total phenol and flavonoid contents were calculated as 10.6 g ± 0.001 gallic acid equivalents/ 100 g dry weight and 2.25±0.004 g quercetin equivalents/100 g dry weight of the extract, respectively. The extract concentration providing 50 % inhibition of DPPH was found as 76.68 μg/ml.
Cinnamomum cassia bark water extract at ≥100 μg/ml concentrations caused significant protection against H2O2-induced oxidative DNA damage in lymphocytes.
Our results support the suggestions that Cinnamomum cassia bark water extract could be beneficial as a prophylactic agent in prevention of oxidative stress-related diseases.
Keywords : Cinnamomum cassia; DPPH; total phenol; total flavonoid; alkaline comet assay