Pentachlorophenol Effect on Auxin Production by <i>Pseudomonas fluorescens</i> GU059580 and Its Application in Wastewater Bioremediation

Abstract

Bioaugmentation by Pseudomonas strains is widely used for the removal of pollutants in wastewater. In this study, we aimed to determine the removal of pentachlorophenol (PCP, 800 mg·L<sup>–1</sup>) in secondary wastewater by the bioaugmentation process. We determined the effects of using three surfactants, namely sodium dodecyl sulfate (SDS), cetyl-tri-methyl-ammonium bromide (CTAB), and Tween 80 for PCP removal. We determined the effect of the role of PCP surfactant for the biofilm and auxin production of the selected bacterial strain of <em>P. fluorescens</em> GU059580. High-performance liquid chromatography and spectroscopic analysis were used to determine PCP removal and bacterial growth, respectively. Biofilm production was determined using 96-well polystyrene plates, and auxin production was determined using spectrophotometric measurement at 535 nm. The results showed the removal of PCP from wastewater by <em>P. fluorescens</em> GU059580 is about 90.12%. The PCP removal from wastewater showed an improvement of about 96.5% after the addition of Tween 80, whereas significant biofilm formation was found in the mineral liquid medium supplemented with PCP and Tween 80, with a value of 3.78. The highest concentration of auxin was found in the presence of PCP without surfactants, showing a value of 1.7 mg·L<sup>–1</sup>. To conclude, <em>P. fluorescens</em> GU059580 can be used in bioreactors or some specific wastewater treatment processes for bioremediation.