Antioxidant activity and phytochemical screening of the methanol extracts of Euphorbia hirta L

摘要

Objective:To assess antioxidant activities of different parts of Euphorbia hirta（E.hirta）,and to search for new sources of safe and inexpensive antioxidants.Methods:Samples of leaves,stems, flowers and roots from E.hirta were tested for total phenolic content,and flavonoids content and in vitro antioxidant activity by diphenyl-1-picrylhydrazyl（DPPH） assay and reducing power was measured using cyanoferrate method.Results:The leaves extract exhibited a maximum DPPH scavenging activity of（72.96±0.78）%followed by the flowers,roots and stems whose scavenging activities were（52.45±0.66）%,（48.59±0.97）%,and（44.42±0.94）%,respectively.The standard butylated hydroxytoluene（BHT） was（75.13±0.75）%.The IC50,for leaves,flowers,roots,stems and BHT were 0.803,0.972,0.989,1.358 and 0.794 mg/mL,respectively.The reducing power of the leaves extract was comparable with that of ascorbic acid and found to be dose dependent. Leaves extract had the highest total phenolic content[（206.17±1.95） mg GAE/g],followed by flowers,roots and stems extracts which were（117.08±3.10） mg GAE/g,（83.15±1.19） mg GAE/g,and （65.70±1.72） mg GAE/g,respectively.On the other hand,total flavonoids content also from leave had the highest value[（37.970±0.003） mg CEQ/g],followed by flowers,roots and stems extracts which were（35.200±0.002） mg CEQ/g,（24.350±0.006） mg CEQ/g,and（24.120±0.004） mg CEQ/ g,respectively.HPTLC bioautography analysis of phenolic and antioxidant substance revealed phenolic compounds.Phytochemical screening of E.hirta leaf extract revealed the presence of reducing sugars,terpenoids,alkaloids,steroids,tannins,flavanoids and phenolic compounds. Conclusions:These results suggeste that E.hirta have strong antioxidant potential.Further study is necessary for isolation and characterization of the active antioxidant agents,which can be used to treat various oxidative stress-related diseases.