Department of Fundamental Microbiology, University of Lausanne, Bâtiment Biophore, Quartier UNIL-Sorge, 1015 Lausanne, Switzerland.
Environ Sci Technol. 2013 Feb 19;47(4):1913-21. doi: 10.1021/es303592c. Epub 2013 Jan 31.
We show proof of principle for assessing compound biodegradation at 1-2 mg C per L by measuring microbial community growth over time with direct cell counting by flow cytometry. The concept is based on the assumption that the microbial community will increase in cell number through incorporation of carbon from the added test compound into new cells in the absence of (as much as possible) other assimilable carbon. We show on pure cultures of the bacterium Pseudomonas azelaica that specific population growth can be measured with as low as 0.1 mg 2-hydroxybiphenyl per L, whereas in mixed community 1 mg 2-hydroxybiphenyl per L still supported growth. Growth was also detected with a set of fragrance compounds dosed at 1-2 mg C per L into diluted activated sludge and freshwater lake communities at starting densities of 10(4) cells per ml. Yield approximations from the observed community growth was to some extent in agreement with standard OECD biodegradation test results for all, except one of the examined compounds.
我们通过流式细胞术直接细胞计数来测量微生物群落随时间的增长，证明了以每升 1-2 毫克碳来评估化合物生物降解的原理。该概念基于这样一种假设，即微生物群落将通过将添加的测试化合物中的碳纳入新细胞来增加细胞数量，而不存在（尽可能多的）其他可同化的碳。我们在假单胞菌属的纯培养物中表明，即使在混合群落中添加每升 1 毫克 2-羟基联苯，也可以用低至 0.1 毫克 2-羟基联苯来测量特定的种群生长。在起始密度为每毫升 10(4)个细胞的稀释活性污泥和淡水湖群落中，用一组香料化合物以每升 1-2 毫克碳的剂量添加，也检测到了生长。从观察到的群落生长中得出的产率估算在某种程度上与所有除一种被检查化合物外的所有化合物的标准 OECD 生物降解测试结果一致。
