Department of Biotechnology, University of Calicut, Malappuram, Kerala, 673635, India.
Biol Trace Elem Res. 2013 Dec;155(3):455-9. doi: 10.1007/s12011-013-9801-x. Epub 2013 Sep 5.
In this paper, we report the dose-dependent antioxidant activity and DNA protective effects of zingerone. At 500 μg/mL, the DPPH radical scavenging activity of zingerone and ascorbic acid as a standard was found to be 86.7 and 94.2 % respectively. At the same concentration, zingerone also showed significant reducing power (absorbance 0.471) compared to that of ascorbic acid (absorbance 0.394). The in vitro toxicity of stannous chloride (SnCl2) was evaluated using genomic and plasmid DNA. SnCl2-induced degradation of genomic DNA was found to occur at a concentration of 0.8 mM onwards with complete degradation at 1.02 mM and above. In the case of plasmid DNA, conversion of supercoiled DNA into the open circular form indicative of DNA nicking activity was observed at a concentration of 0.2 mM onwards; complete conversion was observed at a concentration of 1.02 mM and above. Zingerone was found to confer protection against SnCl2-induced oxidative damage to genomic and plasmid DNA at concentrations of 500 and 750 μg/mL onwards, respectively. This protective effect was further confirmed in the presence of UV/H2O2-a known reactive oxygen species (ROS) generating system-wherein protection by zingerone against ROS-mediated DNA damage was observed at a concentration of 250 μg/mL onwards in a dose-dependent manner. This study clearly indicated the in vitro DNA protective property of zingerone against SnCl2-induced, ROS-mediated DNA damage.
本文报道了荜澄茄素的剂量依赖性抗氧化活性和 DNA 保护作用。在 500μg/mL 时，荜澄茄素和抗坏血酸（作为标准）的 DPPH 自由基清除活性分别为 86.7%和 94.2%。在相同浓度下，荜澄茄素的还原能力（吸光度 0.471）也明显高于抗坏血酸（吸光度 0.394）。采用基因组和质粒 DNA 评估了氯化亚锡（SnCl2）的体外毒性。SnCl2 诱导的基因组 DNA 降解在浓度为 0.8mM 及以上时开始发生，在 1.02mM 及以上时完全降解。对于质粒 DNA，从浓度为 0.2mM 开始，观察到超螺旋 DNA 转化为开放环状形式，表明 DNA 切口活性；在浓度为 1.02mM 及以上时，完全转化。荜澄茄素在 500μg/mL 和 750μg/mL 及以上浓度时，分别对 SnCl2 诱导的基因组和质粒 DNA 的氧化损伤提供保护作用。在存在 UV/H2O2（一种已知的活性氧（ROS）生成系统）的情况下，这种保护作用得到了进一步证实，在浓度为 250μg/mL 及以上时，荜澄茄素以剂量依赖的方式对 ROS 介导的 DNA 损伤提供保护。本研究清楚地表明了荜澄茄素对 SnCl2 诱导的 ROS 介导的 DNA 损伤的体外 DNA 保护特性。
