Bioremediation processes based on biofilms are usually very effective. The presence of (bio)surfactants in such processes can increase bioavailability of hydrophobic pollutants in aqueous phase. However, surfactants can affect the biofilm as well as individual microbial cells in different ways. Biosurfactants produced by a microbial population can be involved in the final structure of biofilm. An external application of synthetic surfactants or 'foreign' biosurfactants often results in partial or complete destruction of the biofilm and their high concentrations also have a toxic effect on microbial cells. Finding a suitable surfactant and its concentration, which would minimize the negative effects mentioned above, would allow to construct effective bioremediation processes using the benefits of both the biofilm and the surfactant. In this context, G(+) bacterium Rhodococcus erythropolis, which has a wide potential for biodegradation of aromatic compounds, was studied. High surface hydrophobicity of its cells, given mainly by the presence of mycolic acids in the cell envelopes, allows formation of stable biofilms. Three synthetic surfactants (Spolapon AOS 146, Novanik 0633A, Tween 80) and rhamnolipid isolated from Pseudomonas aeruginosa were used. Changes in initial adhesion and biofilm formation caused by the surfactants were monitored in a flow cell equipped with hydrophilic/hydrophobic carriers and analyzed by image analysis.
- MeSH
- aromatické uhlovodíky metabolismus MeSH
- biodegradace účinky léků MeSH
- biofilmy účinky léků MeSH
- fenoly metabolismus MeSH
- hydrofobní a hydrofilní interakce účinky léků MeSH
- látky znečišťující životní prostředí metabolismus MeSH
- micely MeSH
- počet mikrobiálních kolonií MeSH
- polyethylen MeSH
- povrchově aktivní látky farmakologie MeSH
- reologie účinky léků MeSH
- Rhodococcus účinky léků růst a vývoj fyziologie MeSH
- techniky vsádkové kultivace MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Reversed phase liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (RP-HPLC/MS-APCI) was used to analyze both synthetic triacylglycerols (TAG) having 1-3 branched fatty acids (FA) in the molecule, and natural TAG prepared by precursor directed biosynthesis from valine, leucine and isoleucine and the corresponding branched short-chain acids in cultivations of Rhodococcus erythropolis. The technique made it possible to identify and quantify TAG differing in a single branched-chain FA. Altogether 11 TAG were synthesized, out of which 8 were synthesized stereospecifically. Branched- and straight-chain-TAG were separated and identified while TAG differing only in iso or anteiso FA could not be separated. The APCI mass spectra of iso-, anteiso- and straight-chain TAG were completely identical. The natural material was found to contain 19 TAG having at least one branched FA. Cultivation on six different substrates showed, apart from the presumed and common incorporation of precursors to iso-even, iso-odd and anteiso FA, also some unusual features such as an increase in the content of odd-FA after the addition of Val (attributed to catabolism of Val to propionate) or the appearance of branched monounsaturated FA. The two-sample paired t test, when applied to the TAG, showed that only the pair Val and isobutyrate differ in incorporation into FA--see, e.g. proportions of M/M/O and brM/brM/O (1.2:1.2 and 1.9:1.2, respectively). Also, incorporation of Val (isobutyrate) yielded only TAG having two branched FA in the molecule, whereas Leu and Ile (isovalerate and 2-methyl-butyrate) gave only TAG with a single branched FA in the molecule.
- MeSH
- antibakteriální látky imunologie terapeutické užití MeSH
- bakteriální léková rezistence genetika imunologie účinky léků MeSH
- biofilmy klasifikace růst a vývoj účinky léků MeSH
- kanamycin terapeutické užití MeSH
- lidé MeSH
- mezibuněčná komunikace genetika imunologie účinky léků MeSH
- Pseudomonas aeruginosa imunologie růst a vývoj MeSH
- Check Tag
- lidé MeSH
