目的考察槲皮素、虎杖苷、染料木素的抗氧化能力及对中波紫外线(UVB)致永生化人角质形成细胞(HaCaT)损伤的保护作用。方法以维生素C为阳性对照药,通过DPPH自由基清除实验,羟基(·OH)自由基清除实验,测定槲皮素、虎杖苷、染料木素不同浓度的抗氧化能力。体外培养HaCaT细胞,与槲皮素、虎杖苷、染料木素100μmol/L共抚育30 mim后,以30 mJ/cm2UVB直接照射细胞,12 h后收集细胞,MTT法检测细胞增殖活性,ELISA法和硫代巴比妥酸(TBA)法分别检测TNF-α、MDA含量,黄嘌呤氧化酶法测定超氧化物歧化酶(SOD)活性。结果槲皮素、虎杖苷、染料木素对DPPH和·OH自由基都具有一定的清除力,其清除能力的大小为染料木素<虎杖苷<槲皮素。UVB辐射对HaCaT细胞造成明显损伤,三种药物作用于HaCaT细胞,与单纯UVB辐射对照组相比,经UVB辐射后各给药组的细胞活性明显增高(P<0.05),TNF-α分泌减少(P<0.05),MDA含量降低(P<0.05),SOD活力增强(P<0.05)。结论三种药物能抑制UVB辐射诱导的HaCaT细胞损伤,促进细胞存活增殖,对UVB辐射损伤的HaCaT细胞具有保护作用,其清除体内自由基,增强细胞的抗氧化能力可能是这些药物抑制UVB辐射诱导HaCaT细胞损伤的作用机制之一。 Objective To investigate the antioxidative capacity of quercetin, polydatin and genistein and the protective effect of UVB on the injury of immortalized human keratinocytes (HaCaT). Methods Vitamin C was used as a positive control. The antioxidant activity of quercetin, polydatin and genistein were tested by DPPH radical scavenging and hydroxyl radical scavenging assay. HaCaT cells were cultured in vitro and co-cultured with quercetin, polydatin and genistein 100 μmol / L for 30 mim. The cells were irradiated with UVB at 30 mJ / cm2. Cells were harvested 12 h later. Cell proliferation was measured by MTT assay. Thiobarbituric acid (TBA) method was used to detect the levels of TNF-α and MDA, and the activity of superoxide dismutase (SOD) was determined by xanthine oxidase method. Results Quercetin, polydatin and genistein had some scavenging activities on DPPH and · OH, and their scavenging capacity was genistein