Radical scavenging activity of flavonoids from Trollius chinensis Bunge

Objective

Flos trollii is considered as functional tea, as well as a traditional medicinal herb, in China. In this study, total phenolic and flavonoid contents of Flos trollii were determined by a colorimetric method. The antioxidative potential of the hydroalcoholic extract of Flos trollii (FTE, extracted by alcohol:water, 80:20) was also evaluated by various antioxidant assays.

Methods

Chemiluminescence technique was used to determine the radical scavenging activities of FTE toward different reactive oxygen species, including superoxide anion (O_-2·), hydroxyl radical (OH·), lipid-derived radicals (R·), and singlet oxygen (¹O₂).

Results

FTE could effectively scavenge O_-2·, OH·, R·, and ¹O₂ at an efficient concentration (EC₅₀) of 46, 5.64, 5.19, and 3.97 mg/mL, respectively. Moreover, the radical scavenging activities of FTE were higher than those of ascorbic acid. Further, FTE had higher 1,1 diphenyl-2-picrylhydrazyl radical (DPPH) radical-scavenging activity with EC₅₀ 44 mg/mL, compared with butylated hydroxytoluenesynthetic antioxidant with EC₅₀ 52 mg/mL.

Conclusion

All results indicated that FTE is a powerful antioxidant, deserving of better utilization of the extracted Flos trollii as antioxidants.