Cotinus coggyria: a rich source of antioxidants

Methanolic extract of Cotinus coggyria Scop. was mixed in distilled water and partitioned first with the n-hexane, then with chloroform, then ethyl acetate and at the end with n-butanol. The phytochemical screening of plant showed presence of the phenolics, cardiac glycosides and flavonoides in large amount in the chloroform, n-butanol and ethyl acetate soluble fraction. Antioxidant activity of these four fractions and the left behind aqueous fraction was measured by four methods such as: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity, ferric thiocyanate assay, ferric reducing antioxidant power (FRAP) assay and total antioxidant activity. Total phenolics were also measured. Noteworthy antioxidant potential was shown by the chloroform, n-butanol and ethyl acetate soluble fraction showed. Ethyl acetate fraction showed highest % inhibition of the DPPH radical when compared with the other studied fractions i.e. 81.64 ± 1.29% inhibition of the DPPH radical at the concentration of 30 μg/ml. Its IC(50) value was found to be 15.58 ± 0.09 μg/ml, comparative to the butylated hydroxytoluene (BHT), which has IC(50) value 12.6 ± 0.85μg/ml. This fraction also showed the highest lipid peroxidation inhibition (61.41 ± 1.16%), as well as highest values of FRAP (697.76 ± 1.98 μg of trolox equivalents) total antioxidant activity (1.02 ± 0.09) and total phenolic contents (229.34 ± 0.57) comparative to the other studied fractions. The chloroform and n-butanol soluble fraction also showed good results for all the studied antioxidant assays.