Giannakis Stefanos, Rtimi Sami, Darakas Efthymios, Escalas-Cañellas Antoni, Pulgarin César
Laboratory of Environmental Engineering and Planning, Department of Civil Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece and Laboratory of Control of Environmental Contamination, Institute of Textile Research and Industrial Cooperation of Terrassa (INTEXTER), Universitat Politècnica de Catalunya, Colom 15, 08222 Terrassa, Catalonia, Spain.
Swiss Federal Institute of Technology, Lausanne, Institute of Chemical Sciences and Engineering, 1015 Lausanne, Switzerland.
Photochem Photobiol Sci. 2015 Dec;14(12):2238-50. doi: 10.1039/c5pp00110b.
In this study, the photoreactivation and the modification of dark repair of E. coli in a simulated secondary effluent were investigated after initial irradiation under different conditions. The simulated solar exposure of the secondary wastewater was followed by exposure to six different low-intensity fluorescent lamps (blacklight blue, actinic blacklight, blue, green, yellow and indoor light) for up to 8 h. When photoreactivation was monitored, blue and green colored fluorescent light led to increased bacterial regrowth. Blacklight lamps further inactivated the remaining bacteria, while yellow and indoor light led to accelerated growth of healthy cells. Exposure to fluorescent lamps was followed by long term storage in darkness, to monitor the bacterial repair in the dark. The response was correlated with the pre-exposure dose of applied solar irradiation, and to a lesser extent with the fluorescent light dose. Bacteria which had undergone extensive exposure showed no response under fluorescent light or during storage in the dark. Finally, the statistical treatment of the data allowed us to suggest a linear model, which is non-selective in terms of the fluorescent light applied. The estimation of the final bacterial population was predicted well (R-sq ∼ 75%) and the photoreactivation risk was found to be more important for cultivable cells.
在本研究中，对不同条件下初次辐照后的模拟二级出水中大肠杆菌的光复活作用及暗修复的改变进行了研究。模拟二级废水经太阳照射后，再用六种不同的低强度荧光灯（蓝黑光、光化黑光灯、蓝光、绿光、黄光和室内光）照射长达8小时。在监测光复活作用时，蓝色和绿色荧光灯导致细菌再生长增加。黑光灯进一步使剩余细菌失活，而黄色和室内光导致健康细胞加速生长。荧光灯照射后在黑暗中进行长期储存，以监测黑暗中的细菌修复情况。该反应与施加的太阳辐照预暴露剂量相关，在较小程度上与荧光灯剂量相关。经历过大量暴露的细菌在荧光灯下或黑暗储存期间无反应。最后，对数据的统计处理使我们能够提出一个线性模型，该模型对所应用的荧光灯是非选择性的。最终细菌数量的估计预测良好（R-sq约为75%），并且发现光复活风险对可培养细胞更为重要。
