Optimization in Pretreatment Conditions for Determination of Heterotrophic Bacteria from Freshwater and Marine Sediments Using Flow Cytometry
应用流式细胞术测定淡水、海洋沉积物中异养细菌前处理条件的选择

The Flow Cytometry (FCM) has been widely used to determine the heterotrophic bacteria in water environment presently. Also, it can be used to determine the heterotrophic bacteria in benthos environment after the appropriate pretreatment. The treatment of extracting sediment-attached bacteria to water environment is the key point of applying the FCM to the study of benthos. This paper discussed the methods of pretreatment for the FCM to detect the heterotrophic bacteria both in freshwater and marine sediments. Results showed that the relatively preferable pretreatment conditions for sediments were: sodium pyrophosphate as the dispersant with the final concentration of 1mmol·L-1 and incubated 10min in dark; sonicate 1min in water bath at 20w, 40KHz power with a manual shake every 30s; and centrifugal extraction 3 times with 2800 r·min-1 at room temperature.