摘要OBJECTIVE:To investigate the efficacy of metha-nol-water extract of Inula helenium root against ox-idative DNA damage.METHODS:Antioxidant properties of metha-nol-water extract of Inula helenium root were re-vealed by 2,2'-azinobis(3-ethylbenzothiazo-line-6-suphonic acid)di-ammonium salt(ABTS),Fo-lin-Ciocalteu and high-performance liquid chroma-tography(HPLC)methods.The effect against oxida-tive DNA base damage was determined analyzing oxidative DNA base damage products by GC-MS/MS.RESULTS:The methanol-water extract of Inula hele-nium root showed good antioxidant capacity[32.20 mg trolox equivalents(TE)/g dried weight(dw)by ABTS method,54.53 mg TE/g dw by chromi-um reducing antioxidant capacity method]and to-tal phenolic content[29.83 mg gallic acid equiva-lent(GAE)/g dw].The chlorogenic acid,ferulic ac-id,rosmarinic acid and caffeic acid were deter-mined in the extract by HPLC.The chlorogenic acid,ferulic acid and Inula helenium root extract were re-vealed to inhibit the oxidative DNA base damage by GC-MS/MS.CONCLUSION:The studies showed a crucial de-crease in the amount of the DNA base damage products when antioxidants were used.The results showed that ferulic acid has better inhibition than chlorogenic acid for DNA oxidation.The metha-nol-water extract of Inula helenium root was deter-mined to inhibit the oxidative DNA damage.