Abstract
In this work, the antioxidant activity and total phenolic compound content of 6 fractions of Smallanthus sonchifolius, Agrimonia pilosa, and Lithospermum erythrorhizon extract were investigated. The highest total phenolic compound contents of each plant extracts were obtained from n-butanol ($13.75{\pm}0.21%$) and methylene chloride ($12.89{\pm}1.10%$) fractions (S. sonchifolius), ethyl acetate ($19.69{\pm}1.02%$) and water ($18.72{\pm}0.76%$) fractions (A. pilosa), and n-butanol ($36.26{\pm}1.26%$) and ethyl acetate ($17.66{\pm}0.94%$) fractions (L. erythrorhizon), respectively. As a result of DPPH radical scavenging activity in 10 mg/mL condition, the highest activity were obtained from n-butanol fraction of S. sonchifolius (81.06%), ethyl acetate fraction of A. pilosa (86.32%), and n-butanol fraction of L. erythrorhizon (82.6%), respectively. Also, the highest reducing power was obtained same fractions as well as DPPH adical scavenging activity. Overall, antioxidant activity has relatively closely connected with contents of total phenolic compounds in S. sonchifolius and L. erythrorhizon extracts.