重金属离子对烤烟叶片中铜锌超氧化物歧化酶活性的影响  

Effects of heavy metal ions on copper-zinc superoxide dismutase activity in flue-cured tobacco leaves

作　　者：邓家军[1,2] 胡继伟[1] 李继新[3] 苏贤坤[3] 黄先飞[1] 刘峰[1] 

机构地区：[1]贵州师范大学贵州省山地环境信息系统与生态环境保护重点实验室,贵阳市宝山北路116号550001 [2]贵州师范大学生命科学学院,贵阳市宝山北路116号50001 [3]贵州省烟草科学研究所,贵阳市威清路334号550003

出　　处：《中国烟草学报》2010年第3期1-6,共6页Acta Tabacaria Sinica

基　　金：教育部科学技术研究重点项目(206135);贵州省高级人才特助经费(TZJF-2006-27);贵州省教育厅自然科学研究重点项目(2005106)

摘　　要：为研究重金属对烟叶铜锌超氧化物歧化酶的作用规律,消除活体烟叶中其它因素的影响,本试验采用离体方法,利用硫酸铵盐析分级分离、乙醇-氯仿沉淀除杂、丙酮再沉淀分级得到只含铜锌超氧化物歧化酶的酶液。研究了不同浓度的Fe2+、Mn2+、Se2+、Sb2+、Cd2+对该酶的影响。结果显示:在浓度为0～100mg/L范围内,Fe2+、Mn2+、Sb2+、Cd2+都能使铜锌超氧化物歧化酶的活性先降低后升高,但在相同浓度下,Cd2+对酶活性的影响最大,其次是Mn2+、Fe2+。Sb2+使该酶的活性的变化趋势与Cd2+、Mn2+基本一致,仅变化幅度不及Cd2+、Mn2+显著。Se2+能降低该酶的活性,当浓度为10mg/L时,酶活性的降低率为58.78%。当Se2+浓度为20mg/L时,酶活性几乎完全丧失。分析了铜锌超氧化物歧化酶活性受Fe2+、Mn2+等影响的可能机制,以期为烟草重金属污染的酶学指标监测系统的建立提供数据支持。In vitro method was applied to study the changing trends in the copper-zinc superoxide dismutase activity caused by heavy metals in order to eliminate influence ofvarious environmental factors. Enzyme solution of copper-zinc superoxide dismutase from tobacco leaves was obtained by using ammonium sulphate to form different levels of precipitates and isolated by using chloroform and alcohol and further cleaned-up with acetone. The effects of Fe2＋,Mn2＋,Se2＋,Sb2＋,and Cd2＋ with different concentrations on copper-zinc superoxide dismutase were studied,and results showed that the activity of copper-zinc superoxide dismutase incresed at first and then decreased in response to increasing Fe2＋,Mn2＋,Sb2＋,or Cd2＋ supply from 0 to 100 mg/L. At the same concentration,however,Cd2＋ exhibited the strongest influence on the change of copper-zinc superoxide dismutase activity,followed by Mn2＋ and Fe2＋. The change of the enzyme activity under the effect of Sb2＋ was similar to,but not more than,that of Cd2＋ or Mn2＋. While Se2＋ can reduce the activity of copper-zinc superoxide dismutase,the decreasing rate of the enzyme activity was 58.78 % in response to the increasing Se2＋ supply of 10 mg/L. When the concentration of Se2＋ reached 20 mg/L,the enzyme activity was almost entirely lost. Copper-zinc superoxide dismutase activities under the effects of heavy metal ions Fe2＋,Mn2＋,Se2＋,Sb2＋,and Cd2＋ can be ascribable to the result that the three main factors interacted. This research may provide useful data for the establishment of zymological indicator systems,which can monitor the potential heavy metal contamination risk during different tobacco growth stages.

关 键 词：烤烟 超氧化物歧化酶 活性 重金属离子 影响 

分 类 号：TS411[农业科学—烟草工业]