外源一氧化氮缓解盐胁迫下杜氏盐藻氧化损伤的初步研究

A Tentative Research of Alleviating Oxidative Damage of Exogenous Nitric Oxide to Dunaliella salina under Salinity Stress

研究外源一氧化氮(NO)供体硝普钠(sodium nitroprusside,SNP)缓解3.0 mol/L NaCl胁迫对杜氏盐藻的氧化损伤作用并探讨其初步机理。结果表明:与单独盐胁迫相比,添加低浓度的SNP(0.5μmol/L和1μmol/L)能促进杜氏盐藻的生长,显著提高其叶绿素含量,并增强了超氧化物歧化酶(SOD)的活性(P<0.05)。其中,1μmol/L SNP处理24 h后SOD活性提高了1.6倍。此外,半定量RT-PCR结果显示,低浓度的SNP(0.5μmol/L和1μmol/L)对盐胁迫下杜氏盐藻Fe-SOD基因的转录具有促进作用,24 h时作用显著(P<0.05),表达量分别提高了21.18%和27.41%,而高浓度的SNP(50μmol/L)抑制Fe-SOD基因的表达,加剧了盐胁迫带来的氧化伤害。

A tentative research of alleviating the oxidative damage of sodium nitroprusside （SNP）, a nitric oxide （NO） donor,to Dunaliella salina under salinity stress of 3.0 mol/L NaCl was explored in this study. The results showed that the addition of low concentrations of SNP （0. 5 μmol/L 和 1 μmol/L） not only promoted the proliferation of Dunaliella salina and increased the content of chlorophyll significantly, but also enhanced the activity of superoxide dismutase （SOD） （P〈0.05）, gaining 1.6 times higher after the application of 1 μmol/L SNP at 24h, compared to sole salinity stress. Furthermore, the results of Semi-quantitative RT - PCR indicated that transcription of the Fe- SOD gene was enhanced significantly by exogenous low concentration SNP （0.5 μmol/L 和 1 μmol/L） at 24h （P〈0. 05） ,with 21.18% and 27.41% ,respectively. The application of high concentration SNP （50μmol/L） inhibited the expression of the Fe- SOD gene, aggravating the oxidative damage on Dunaliella salina under salinity stress.