Synergistic effect of biofilm growth and cadmium adsorption via compositional changes of extracellular matrix in montmorillonite system

Bioresour Technol. 2020 Nov:315:123742. doi: 10.1016/j.biortech.2020.123742. Epub 2020 Jun 30.

Abstract

The interaction of bacterial biofilm and clay minerals provides great potential for heavy metal remediation in contaminated soil, yet, little is known about how heavy metal, clay minerals and their combinations affect the bacterial biofilm performance and heavy metal adsorption. In this study, the response of biofilm development as well as Cd2+ adsorption in the presence of Cd2+ and montmorillonite has been deciphered. Low concentrations of Cd2+ and montmorillonite or their combinations enhanced biofilm formation by increasing polysaccharides proportion in the biofilm matrix, and the maximum adsorption capacity of Cd2+ by biofilm was increased by 1.5 times. Furthermore, the immobilization of Cd2+ by soil was significantly improved when S14-biofilm was introduced. Such results could gain deeper insight into bacterial survival tactics in the complex systems which makes major contribution to microbial remediation of heavy metal polluted environments.

Keywords: Biofilm; Bioremediation; Cd(2+); Extracellular polymeric substance; Montmorillonite.

MeSH terms

  • Adsorption
  • Bentonite
  • Biofilms
  • Cadmium*
  • Extracellular Matrix
  • Soil
  • Soil Pollutants / analysis*

Substances

  • Soil
  • Soil Pollutants
  • Cadmium
  • Bentonite