College of Environment and Planning, Henan University, Kaifeng 475004, PR China.
Mar Pollut Bull. 2012 Jun;64(6):1106-11. doi: 10.1016/j.marpolbul.2012.04.006. Epub 2012 Apr 30.
The aim of this study was to investigate the effect of nitrate on nitrite toxicity to Microcystis aeruginosa. Short-term uptake experiment revealed nitrate could depress the nitrite active uptake. The long-term experiment of nitrate effects on nitrite toxicity showed a negative relationship between the growth and intracellular nitrite levels of M. aeruginosa. The net nitrite uptake displayed a decline in the range of 0-150 mg NO(3)(-)-NL(-1) and an elevation at 200mg NO(3)(-)-NL(-1), whereas the activities of nitrate reductase (NR) were more sensitive to nitrate than nitrite reductase (NiR). As a result, the total intracellular nitrite levels tended to decrease up to 100 mg NO(3)(-)-NL(-1) then increased at 150-200 mg NO(3)(-)-NL(-1). These results suggested the existence of external nitrate could affect the toxicity of nitrite to alga through changing intracellular nitrite content.
本研究旨在探讨硝酸盐对铜绿微囊藻亚硝酸毒性的影响。短期吸收实验表明，硝酸盐可以抑制亚硝酸的主动吸收。硝酸盐对亚硝酸毒性影响的长期实验表明，铜绿微囊藻的生长与细胞内亚硝酸水平之间呈负相关关系。硝酸盐在 0-150mgNO3--N/L 范围内的净亚硝酸吸收呈下降趋势，在 200mgNO3--N/L 时升高，而硝酸还原酶 (NR) 的活性比亚硝酸还原酶 (NiR) 对硝酸盐更敏感。因此，细胞内总亚硝酸水平在 100mgNO3--N/L 以下时呈下降趋势，在 150-200mgNO3--N/L 时升高。这些结果表明，外部硝酸盐的存在可能通过改变细胞内亚硝酸含量来影响亚硝酸对藻类的毒性。
