Department of Civil and Environmental Engineering, University of Trento, via Mesiano, 77, 38050 Trento, Italy.
Water Res. 2010 Jul;44(13):3807-18. doi: 10.1016/j.watres.2010.04.027. Epub 2010 Apr 29.
A rapid multi-step procedure, potentially amenable to automation, was proposed for quantifying viable and active bacterial cells, estimating their biovolume using flow cytometry (FCM) and to calculate their biomass within the main stages of a wastewater treatment plant: raw wastewater, settled wastewater, activated sludge and effluent. Fluorescent staining of bacteria using SYBR-Green I + Propidium Iodide (to discriminate cell integrity or permeabilisation) and BCECF-AM (to identify enzymatic activity) was applied to count bacterial cells by FCM. A recently developed specific procedure was applied to convert Forward Angle Light Scatter measured by FCM into the corresponding bacterial biovolume. This conversion permits the calculation of the viable and active bacterial biomass in wastewater, activated sludge and effluent, expressed as Volatile Suspended Solids (VSS) or particulate Chemical Oxygen Demand (COD). Viable bacterial biomass represented only a small part of particulate COD in raw wastewater (4.8 +/- 2.4%), settled wastewater (10.7 +/- 3.1%), activated sludge (11.1 +/- 2.1%) and effluent (3.2 +/- 2.2%). Active bacterial biomass counted for a percentage of 30-47% of the viable bacterial biomass within the stages of the wastewater treatment plant.
提出了一种快速的多步程序，该程序可能适合自动化，用于定量活细菌和活性细菌细胞，使用流式细胞术（FCM）估计其生物体积，并计算污水处理厂主要阶段的生物量：原废水、沉淀废水、活性污泥和出水。使用 SYBR-Green I + Propidium Iodide（区分细胞完整性或通透性）和 BCECF-AM（识别酶活性）对细菌进行荧光染色，通过 FCM 对细菌细胞进行计数。应用最近开发的特定程序将 FCM 测量的前向角光散射转换为相应的细菌生物体积。这种转换允许计算废水中、活性污泥中和出水中的活细菌和活性细菌生物量，以挥发性悬浮固体（VSS）或颗粒化学需氧量（COD）表示。在原废水（4.8 +/- 2.4%）、沉淀废水（10.7 +/- 3.1%）、活性污泥（11.1 +/- 2.1%）和出水（3.2 +/- 2.2%）中，活细菌生物量仅占颗粒 COD 的一小部分。在污水处理厂的各个阶段，活性细菌生物量占活细菌生物量的 30-47%。
