Biodegradation and surfactant-mediated biodegradation of diesel fuel by 218 microbial consortia are not correlated to cell surface hydrophobicity

Abstract

In this study, we elucidated the role of cell surface hydrophobicity (microbial adhesion to hydrocarbons method, MATH) and the effect of anionic rhamnolipids and nonionic Triton X-100 surfactants on biodegradation of diesel fuel employing 218 microbial consortia isolated from petroleum-contaminated soils. Applied enrichment procedure with floating diesel fuel as a sole carbon source in liquid cultures resulted in consortia of varying biodegradation potential and diametrically different cell surface properties, suggesting that cell surface hydrophobicity is a conserved parameter. Surprisingly, no correlations between cell surface hydrophobicity and biodegradation of diesel fuel were found. Nevertheless, both surfactants altered cell surface hydrophobicity of the consortia in similar manner: increased for the hydrophilic and decreased for the hydrophobic cultures. In addition to this, the surfactants exhibited similar influence on diesel fuel biodegradation: Increase was observed for initially slow-degrading cultures and the opposite for fast degraders. This indicates that in the surfactant-mediated biodegradation, effectiveness of surfactants depends on the specification of microorganisms and not on the type of surfactant. In contrary to what was previously reported for pure strains, cell surface hydrophobicity, as determined by MATH, is not a good descriptor of biodegrading potential for mixed cultures.

Alteration in cell surface properties of Burkholderia spp. during surfactant-aided biodegradation of petroleum hydrocarbons

“…This phenomenon is influenced by CSH of the microorganisms. Changes in CSH during petroleum hydrocarbon degradation in the presence of surfactants have been reported by various researchers (Zhao et al 2011;Owsianiak et al 2009;Hua et al 2003;Zhang and Miller 1994). Zhang and Miller (1994) observed that the biosurfactant rhamnolipid increased the CSH of the slow degraders and this enhanced the rate of degradation of octadecane by two strains of P. aeruginosa.…”

“…Zhang and Miller (1994) observed that the biosurfactant rhamnolipid increased the CSH of the slow degraders and this enhanced the rate of degradation of octadecane by two strains of P. aeruginosa. Owsianiak et al (2009) reported that rhamnolipid and Triton X-100 modified the CSH (as determined by BATH assay) of a microbial consortia during biodegradation of diesel fuel, but this increase was not correlated with increase in hydrocarbon degradation. Zhao et al (2011) illustrated different effects of rhamnolipid addition on phenanthrene degradation by a hydrophobic Bacillus subtilis strain and a hydrophilic P. aeruginosa strain.…”

Effect of external voltage on Pseudomonas putida F1 in a bio electrochemical cell using toluene as sole carbon and energy source

“…Stimulation of bioremediation by electrokinetic processes has been reported in a series of studies (LeDuc & Terry, 2005;Owsianiak et al, 2009;Pandey et al, 2009). Optimal biodegradation activity requires that the direct current does not have any negative effects on the physiology of the degrading bacteria.…”

Predictable bacterial composition and hydrocarbon degradation in Arctic soils following diesel and nutrient disturbance

“…sed., Comamonadaceae and Rhodocyclaceae were present. Members of most of these families are known to be capable of degrading hydrocarbons (Pepi et al, 2003;Castorena et al, 2006;Owsianiak et al, 2009;Mbadinga et al, 2011), so it was interesting that the relative abundance of these assemblages in contaminated soils did not correlate with degradation. Instead, they likely identify an initial soil parameter that is important for hydrocarbon degradation, such as moderate pH.…”