Protective affect against hydroxyl radical induced DNA damage and antioxidant mechanism of Begonia fimbristipula

Abstract

Begonia fimbristipula; DNA damage; Hydroxyl radical

As a tea or functional vegetable in southeast China, Begonia fimbristipula Hance possesses various pharmacological effects including antioxidant ability. However, its antioxidant effect has not been reported yet. The objective of this work was to investigate its antioxidant ability, then further discuss the antioxidant mechanism. B.fimbristipula Hance was extracted by methanol to obtain methanol extract of B.fimbristipula Hance (EBFH). EBFH was then measured by various antioxidant methods, including DNA damage assay, 2,2-Diphenyl-1-picrylhydrazyl radical (DPPH•) assay, superoxide anion radical (O2• - ) scavenging assay, 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonate radical (ABTS• + ) assay, Fe3+ -reducing assay and Cu2+ -reducing assay. The total phenolic content of EBFH was estimated using Folin-Ciocalteu method as well. Our results revealed that EBFH could effectively protect against hydroxyl-induced DNA damage. In addition, it could also scavenge O2• - , DPPH• and ABTS• + radicals, and reduce Fe3+ and Cu2+. The total phenols content of EBFH was 133.25 ± 2.88 pyrogallol/g. In conclusion, B.fimbristipula Hance can effectively protect against hydroxyl-induced DNA damage. One mechanism of this protective effect may be radical scavenging via donating hydrogen atom (H•), donating electron (e). Its antioxidant ability may be mainly attributed to the total phenols, especially cyanidin-3-Oglucoside.