Evaluation of the growth inhibition strength of hydrocarbon solvents against Escherichia coli and Pseudomonas putida grown in a two-liquid phase culture system consisting of a medium and organic solvent

• Published in: Extremophiles : life under extreme conditions 2001-02, Vol.5 (1), p.11-15
• Main Authors: AONO, Rikizo, TSUKAGOSHI, Norihiko, MIYAMOTO, Toshiyuki
• Format: Article
• Language: English
• Subjects: Action of physical and chemical agents on bacteria; Bacteriology; Biological and medical sciences; Culture Media; Escherichia coli - drug effects; Escherichia coli - growth & development; Fundamental and applied biological sciences. Psychology; Hydrocarbons - pharmacology; Microbiology; Pseudomonas putida - drug effects; Pseudomonas putida - growth & development; Solvents - pharmacology; Space life sciences
• ISSN: 1431-0651; 1433-4909
• DOI: 10.1007/s007920000167

The growth of microorganisms is often inhibited in a two-liquid phase culture system consisting of an aqueous medium and a large volume of hydrophobic solvent. Escherichia coli and Pseudomonas putida were cultured in a two-phase system containing a solvent with a log Pow value in a range of 2.1 to 6.0. The increase in the cell mass was monitored by increase in turbidity of the medium phase. We devised a semiquantitative method to evaluate the growth inhibition strength of solvents based on the relative amount of bacterial growth occurring in the two-phase system. Analyses of growth of the bacteria by this method showed that the growth inhibition strength of a given solvent was usually but not always correlated inversely with its polarity. It is clear that growth inhibition strength is not determined simply by polarity of the solvent.