| 摘要: |
| 以坛紫菜（Pyropia haitanensis）叶状体为材料，测定了其在不同光强强度胁迫下细胞内超氧阴离子自由基（O-2·）、过氧化氢（H2O2）、羟自由基（·OH）、丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性、还原型谷胱甘肽（GSH）含量、抗坏血酸过氧化物酶（APX）活性、过氧化氢酶（CAT）活性的变化.结果表明，在光强为200 μmol/（m2·s）即检测到了O-2·含量的显著上升，而当光强继续升高至500 μmol/（m2·s）以上时，O-2·含量开始显著减少，H2O2和·OH含量开始显著上升；SOD和CAT的酶活伴随光强升高而呈现为逐渐下降的趋势，GSH的含量在光强超过500 μmol/（m2·s）时显著下降，只有APX酶活在整个高光强胁迫过程中呈现为活性逐渐增强的趋势.这些结果说明，坛紫菜细胞内存在着一套应答高光强胁迫的活性氧清除机制，APX在其中发挥重要作用.但当光强超过500 μmol/（m2·s）以上时，坛紫菜细胞内的活性氧清除机制难以满足活性氧清除的需要，氧化性更强的·OH迅速积累，引起细胞膜脂的严重损伤. |
| 关键词: 海洋生物学 坛紫菜 高光胁迫 活性氧 抗氧化系统 |
| DOI：10.3969/J.ISSN.2095-4972.2016.03.011 |
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| 基金项目:国家863计划资助项目（2012AA10A411）；国家自然科学基金资助项目（41176151，41276177）；福建省种业创新与产业化工程资助项目（2014S1477 10）；福建省自然科学基金资助项目（2014J05041, 2014J07006） |
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| Analysis of physiological indexes in blades of Pyropia haitanensis under high light stress |
| CHEN Ludan,XU Kai,XU Yan,JI Dehua,CHEN Changsheng,XIE Chaotian |
| (College of Fisheries， Jimei University， Xiamen 361021， China) |
| Abstract: |
| In this study， the physiological responses of the blades of Pyropia haitanensis under different intensities of high light stress were analyzed. Reactive oxygen species （ROS） including superoxide anion free radical （O-2·）， H2O2 and hydroxyl free radical（·OH）， reduced glutathione （GSH）， malondialdehyde （MDA） content， the activities of superoxide dismutase （SOD）， catalase （CAT） and ascorbate peroxidase （APX） were measured. The results show that the content of O-2· in the P. haitanensis cell significantly increased when the illumination intensity was 200 μmol/（m2·s）， but as the illumination intensity increase continually， the content of O-2· significantly decreased. When the illumination intensity higher than 500 μmol/（m2·s）， the contents of H2O2 and ·OH increased significantly. During the high light stress， the activities of SOD and CAT decreased gradually. The content of GSH decreased with increasing APX activity when illumination intensity was higher than 500 μmol/（m2·s）. These results suggest that the mechanism of ROS scavenging is exist in the blades of P. haitanensis and APX plays important role in removing ROS during high light stress. However， when the illumination intensity was higher than 500 μmol/（m2·s） and the mechanism can't meet the requirement of ROS scavenging， the significant increase of ·OH begins to damage the blade cells． |
| Key words: marine biology Pyropia haitanensis high light stress reactive oxygen species （ROS） antioxidant system |
