Enhancing bacterial transport with saponins in saturated porous media for the bioaugmentation of groundwater: visual investigation and surface interactions
The success of bioaugmentation processes for the remediation of groundwater contamination relies on effective transport of the injected microorganisms in a subsurface environment. Biosurfactants potentially affect bacterial attachment and transport behavior in porous media. Although saponins as biosurfactants are abundant in nature, their influence on bacterial transport in groundwater systems remains unknown. In this research, tank visual-transport experiments, breakthrough curve monitoring, and surface property measurement were performed to evaluate the effects of saponins on the transport of Pseudomonas migulae AN-1 cells, which were used as a model bacterium in saturated sand. Results show that the 0.1% saponins could effectively facilitated the AN-1 secondary transport and the addition of saponins decreased the hydrophobicity of AN-1 and sand. The role of the promotion of saponins was more dominant than that of the inhibition of ions on AN-1 transport in a saturated porous medium when ions and saponins coexisted. The interactions between AN-1 and sand grains with saponins and ions were explained in accordance with the Derjaguin–Landau–Verwey–Overbeek theory.
KeywordsSaponins Bacterial transport Bioaugmentation Groundwater remediation DLVO
This study was funded by the National Natural Science Foundation of China (Grant No. 41530636).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
This article does not contain any studies with human participants or animals performed by any of the authors.
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