Premium
Rapid fluorometric assay of bacterial density in lake water and seawater
Author(s) -
Tranvik Lars J.
Publication year - 1997
Publication title -
limnology and oceanography
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.7
H-Index - 197
eISSN - 1939-5590
pISSN - 0024-3590
DOI - 10.4319/lo.1997.42.7.1629
Subject(s) - seawater , environmental chemistry , extraction (chemistry) , bacteria , chemistry , fluorescence , reagent , chromatography , environmental science , biology , ecology , genetics , physics , quantum mechanics
This paper describes a rapid fluorometric method for the determination of bacterial densities ranging from 10 5 to 10 7 ml −1 by using the double‐stranded DNA stain PicoGreen. Reagents are added to water samples (200 µ l) without concentration of the bacteria or laborious extraction of bacterial DNA. The method works well both in lake water, including humic water with high background fluorescence, and in seawater. The PicoGreen assay successfully replaces time‐consuming microscopy for counts of bacterial cultures and can be used in natural water samples as well. In samples from 12 lakes representing a wide range of bacterial and algal concentrations, DNA content was closely correlated with bacterial numbers ( r = 0.96).