Effects of two surfactants on microbial diversity of a PCE-degrading microbial consortium

The effects of two representative surfactants, Rhamnolipids and Tween 80, on the microbial diversity of a PCE-degrading consortium during surfactant-enhanced biodegradation, were explored. The biodegradation efficiency was increased from 47.25% to 73.44%, and 47.25%-66.69%, with the addition of Rhamnolipid at 10 mg/L and Tween 80 at 50 mg/L, respectively. PCE biodegradation kinetics can be described by the pseudo-first-order reaction model for both scenarios. Analyses of alpha and beta indices of the microbial consortium showed that the microbial diversity of both groups exposed to either surfactant was not significantly different from the PCE only group. However, the bacterial abundance in the consortium changed significantly at both the phylum and genus levels. The results demonstrated that the composition of the PCE-degrading consortium is relatively stable, but the exposure to both surfactants results in the enrichment of some genera, which could contribute to the increased biodegradation efficiency. (C) 2020 Elsevier Ltd. All rights reserved.