Antioxidant proprieties of methanolic and ethanolic extracts of Euphorbia helioscopia, (L.) aerial parts

Sun spurge plants (Euphorbia helioscopia, L.) were collected from the north of Tunisia. Dried plant parts namely flowers, leaves and stem were individually extracted with methanol and ethanol. Extracts were screened for their antioxidant activity using the 1,1-Diphenyl-2-picrylhydrazyl (DPPH) free radical test. Total phenolics and total flavonoids amounts were also measured. The highest radical scanvenging effect was observed in flowers methanolic extract with IC50 value of 26.66 ± 0.000μg/ml. While, relatively poorer antioxidant activity were observed in the same extracts of leaves and stem with respective IC50 values of 65.25 ± 0.004 and 80.17± 0.012 μg/ml. The IC50 values ranged from 27.55 ± 0.005 to 179.02 ± 0.957μg/ml in ethanol extracts of the above mentioned tested samples. Polyphenols and total flavonoids amounts varied in significant way among tested aerial parts of Euphorbia helioscopia and among two used solvents, the highest phenolics and flavonoids contents were found in methanolic flowers extracts (51.49 ± 0.012 mg GAE/g dry weights, 11.38 ± 0.004 mg QE/dry weight respectively). However, ethanol extract of stem gave the lowest amounts of total phenolics and flavonoids (4.80 ± 0.001 mg GAE/g dry weight and 1.69 ± 0.001 mg QE/dry weight respectively).