Using Microbial Biofilms to Enhance the Phytoremediation of Contaminants in Soil and Water. Part B: The Sustainable Biodegradation of Phenolic Endocrine-disrupting Chemicals by Bacteria in the Rhizosphere of Phragmites australis
Tadashi Toyama and Kazuhiro Mori
from: Biofilms in Bioremediation: Current Research and Emerging Technologies (Edited by: Gavin Lear). Caister Academic Press, U.K. (2016) Pages: 241-248.
Rhizoremediation, the degradation and removal of pollutants by exploiting the elevated microbial activity in the rhizosphere of plants, has gained much attention in recent years. In this second part of this chapter, we discuss the use of two rhizobacteria (Sphingobium fuliginis TIK1 and Sphingobium sp. IT4) colonizing the root of the common reed Phragmites australis, and the use of this association for the sustainable treatment of water polluted with phenolic endocrine-disrupting chemicals (EDCs). Strains TIK1 and IT4, isolated from Phragmites rhizospheres, degrade various phenolic EDCs (4-alkylphenols and bisphenols). The root exudates of Phragmites appeared to facilitate the degradation activity of these, using the exudates as a source of carbon and energy for cell growth. Additionally, the roots provide a large surface area for bacterial colonisation. Phragmites plants inoculated with these bacteria (i.e., both Phragmites-strain TIK1 and Phragmites-strain IT4 associations) were able to simultaneously and repeatedly remove various phenolic EDCs from polluted water. We conclude that the use of hydroponic systems using Phragmites-TIK1 and Phragmites-IT4 associations would be an effective strategy for the sustainable treatment of polluted waters contaminated by mixtures of phenolic EDCs read more ...