蓝藻伪空胞的测定及其前处理方法研究

目的]探讨蓝藻伪空胞的测定及其前处理方法。方法]改进了测定伪空胞的毛细管压力法,对改进后的装置进行了检测限和精密度测试,并研究了2种浓缩方法和2种保存方法对3种蓝藻细胞数量和伪空胞含量的影响。结果]改进后的蓝藻伪空胞测定装置其检测限达到0.001 8μl/m l藻液,同一样品测定结果相对标准偏差小于1%。采用过滤和离心2种浓缩方法时,分散单细胞的微囊藻细胞损失都大于50%,其中小群体的微囊藻采用离心的方法细胞损失较小,而丝状的颤藻采用过滤的方法损失较小;这2种方法对伪空胞含量的影响均可忽略。3种蓝藻在直接冷藏和添加鲁哥试剂保存7 d后,其细胞浓度和单位细胞的伪空胞含量均未发生明显改变,其中对于伪空胞,直接冷藏的损失更小;对于自然水体样品,宜添加鲁哥试剂进行保存。结论]为研究蓝藻浮力调节机制及其暴发机理提供了理论依据。

Measurement of Gas Vacuole in Cyanobacteria and Its Pretreatment Method

Objective] The aim was tomeasure gas vacuole in cyanobacteria and discuss its pretreatmentmethod.Method] The capillary pressure method to determ ine gas vacuole in cyanobacteria wasmodified firstly,and then the lower detection lim it and precision ofmodified apparatuswere tested,finally the effects of two concentration methods and preservation methods on cell number and gas vacuole of cyanobacteria were studied.Result] The lower detection lim it and relative standard deviation ofmodified apparatus to measure gas vacuole in three kinds of cyanobacteria were 0.001 8μl/m l and 1%,respectively.UnicellularM icrocystiscouldn’tbe concentrated effectively by filtration or centrifugation method,and the lost rate reached 50%.However,the colony of Microcystisand filamentousPlanktothrixmougeotiicould be concentrated by centrifugation and filtration method,respectively,with lower loss rate.After preserved by direct refrigeration and adding Lugol’s iodine solution for 7 d,there was no obvious change in cell concentration and gas vacuole content per cell,and the loss of direct refrigeration was small for gas vacuole,while the pres-ervation of natura water samples should add Lugol’s iodine solution.Conclusion] The study could provide theoretical foundation for the resear-ches on buoyancy regulation mechanism and of cyanobacteria.