磷恢复对磷饥饿铜绿微囊藻光合色素和部分抗氧化酶活性的影响

Effects of Phosphorus Recovery on Photosynthetic Pigments and Some Antioxidant Enzymes Activities of Phosphorus Starved Microcystis aeruginosa

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(H_(2)O_(2))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2.54×10^(7)cell·mL^(-1),显著低于对照组(3.11×10^(7)cell·m L^(-1))。磷恢复144 h后,处理组藻细胞密度为4.05×10^(7)cell·mL^(-1),仍显著低于对照组(4.32×10^(7)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、1.44μg·mL^(-1)和0.031、0.02、0.065 mg·L^(-1);MDA、H_(2)O_(2)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、H_(2)O_(2)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。

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 2.54×10^(7) cell·mL^(-1),significantly lower than that of the control group(3.11×10^(7) cell·mL^(-1)).After 144 h of phosphorus recovery,the algae density in the treatment group was 4.05×10^(7) cell·mL^(-1),significantly lower than that of the control group(4.32×10^(7) cell·mL^(-1)).The contents of chl-a,carotenoids and PC,APC,PE showed a trend of gradual increase,which were 5.96、1.44μg·mL^(-1) and 0.031,0.02,0.065 mg·L^(-1) at 144 h.The contents of MDA,H_(2)O_(2) 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,H_(2)O_(2) 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.