Abstract:

In order to explore the effects of phosphorus starvation and phosphorus recovery on the physiological indexes of Microcystis aeruginosa， its cells were treated with phosphorus starvation for 7 d and then phosphorus recovery was carried out. The cell density， the contents of chlorophyll a （chl-a）， carotenoids， phycocyanin （PC）， allophycocyanin （APC）， phycoerythrin （PE）， malondialdehyde （MDA）， hydrogen peroxide （H₂O₂） and superoxide dismutase （SOD） activity were determined. The results showed that the density of M.aeruginosa was 2.54×10⁷ cell·mL^-1， significantly lower than that of the control group （3.11×10⁷ cell·mL^-1）. After 144 h of phosphorus recovery， the algae density in the treatment group was 4.05×10⁷ cell·mL^-1， significantly lower than that of the control group （4.32×10⁷ cell·mL^-1）. The contents of chl-a， carotenoids and PC， APC， PE showed a trend of gradual increase， which were 5.96、1.44 μg·mL^-1 and 0.031， 0.02， 0.065 mg·L^-1 at 144 h. The contents of MDA， H₂O₂ and the activity of SOD all increased first and then decreased， and reached the maximum value at 48 h， which increased by 36.2%， 47.7% and 51.1%， respectively， compared with the control group. In conclusion， the cell density and the contents of Chla， carotenoid， phycobiliprotein of M. aeruginosa increased after phosphorus recovery， but it was difficult to recover to control level. The changes of MDA， H₂O₂ contents and SOD activity indicated that M.aeruginosa cells were damaged by oxidation and the cell membrane system was damaged by phosphorus starvation and phosphorus recovery

Key words: phosphorus recovery, phosphorus starvation, Microcystis aeruginosa, photosynthetic pigments, phycobili protein, antioxidant enzymes

摘要：

为探究磷饥饿及磷恢复对铜绿微囊藻光合色素、藻胆蛋白和抗氧化酶等生理指标的影响，将其进行磷饥饿处理7 d后再进行磷恢复，检测磷恢复前后铜绿微囊藻的藻细胞密度、叶绿素a、类胡萝卜素、藻蓝蛋白（phycocyanin，PC）、别藻蓝蛋白（allophycocyanin，APC）、藻红蛋白（phycoerythrin，PE）、丙二醛（malondialdehyde，MDA）和过氧化氢（H₂O₂）含量及超氧化物歧化酶（superoxide dismutase，SOD）活性的变化。结果表明，铜绿微囊藻磷饥饿处理7 d后，藻细胞密度为2.54×10⁷ cell·mL^-1，显著低于对照组（3.11×10⁷ cell·mL^-1）。磷恢复144 h后，处理组藻细胞密度为4.05×10⁷ cell·mL^-1，仍显著低于对照组（4.32×10⁷ cell·mL^-1）；叶绿素a、类胡萝卜素和PC、APC、PE含量均呈现升高趋势，在144 h时分别达到5.96、1.44 μg·mL^-1和0.031、0.02、0.065 mg·L^-1；MDA、H₂O₂含量和SOD活性呈先上升后下降趋势，均在48 h达到最大值，较对照组分别增加36.2%、47.7%、51.1%。由此表明，磷恢复后铜绿微囊藻的藻细胞密度、叶绿素a、类胡萝卜素和藻胆蛋白含量虽呈升高趋势，但难以恢复到对照水平；MDA、H₂O₂含量及SOD活性的变化也说明，从磷饥饿到磷恢复后铜绿微囊藻藻细胞受到氧化损伤，并对细胞膜系统产生破坏。

关键词: 磷恢复, 磷饥饿, 铜绿微囊藻, 光合色素, 藻胆蛋白, 抗氧化酶