氯霉素对EBPR系统除磷性能的影响及其机制

Effects of chloramphenicol on phosphorous removal capacity of EBPR system and its mechanism

目的探究氯霉素(chloramphenicol,CAP)(0.01~3mmol/L)对强化生物除磷(EBPR)系统除磷性能的影响及其机制。方法采用活性污泥构建EBPR系统,测定CAP对该系统除磷性能的影响,分析CAP对聚磷菌(polyphosphate accumulating organisms,PAOs)代谢中间产物(聚羟基烷酸酯、糖原)代谢及关键酶(多聚磷酸盐激酶、多聚磷酸盐酯酶和腺苷酸激酶)活性的影响。结果 0.01~3mmol/L CAP对EBPR系统的除磷抑制率介于-6.08%~100%。较高浓度的CAP(≥1mmol/L)可破坏好氧阶段聚羟基烷酸酯与糖原的正常代谢(P<0.05),对除磷关键酶活性也存在不同程度的显著抑制(P<0.05)。结论 CAP(0.3~3mmol/L)可影响EBPR系统中PAOs体内好氧段聚羟基烷酸酯及糖原的代谢及抑制除磷关键酶的活性,使得系统的除磷性能减弱,低浓度(0~0.1mmol/L)CAP对EBPR系统无明显不利影响。

Objective To explore the effects of chloramphenicol(CAP)(0.01~3 mmol/L) on phosphorus removal capacity in EBPR system and its mechanism. Methods Using activated sludge to construct EBPR system and then determine the effects of CAP on metabolic intermediates(polyhydroxyalkanoates and glycogen) and the activity of key enzymes(exopolyphosphatase, adenylate kinase, and polyphosphate kinase) of polyphosphate accumulating organisms(PAOs). Results The inhibition rates of phosphorus removal were ranged from-6.08% to 100% under the mass concentration range of 0.01 to 3 mmol/L CAP. The normal metabolism of polyhydroxyalkanoates and glycogen was destroyed at high CAP concentrations(≥1 mmol/L)(P<0.05), the activity of key enzymes related to phosphorus removal was also inhibited(P<0.05). Conclusions CAP(0.3~3 mmol/L) can affect metabolism of polyhydroxyalkanoates and glycogen of PAOs and inhibit the activity of key enzymes related to phosphorus removal in EBPR system, and then weaken the phosphorous removal capacity. No significant effects were found when the exposure concentration of CAP was low(0.01~0.1 mmol/L).