Interaction Between Micropollutants and Degradative Biofilm Communities : Basis for a Biomimetic Approach to Water Treatment

[摘要] ENGLISH ABSTRACT: The remediation and reclamation of water has become a critically important issue, as the use of water as aconduit of waste has resulted in the contamination of a resource that life on Earth cannot function without.Research has shown that pollutants at trace levels, or micropollutants, are not being removed adequately fromtreated water and, in some cases, the micropollutant concentrations actually increase following treatment.Microbial aggregates, such as biofilms, are important constituent in wastewater treatment, in bothconventional wastewater treatment plants (WWTPs) and in new-generation alternatives such as biomimicrybasedconstructed wetlands. This project was conducted in the paradigm of biomimicry, the concept of usinginspiration from nature to provide innovative solutions to anthropogenic problems. The aim of the study wastwo-fold; namely 1) to investigate the laboratory-based degradation of selected micropollutants by biofilms,with microbial activity as the key driver of biodegradation and, 2) to extrapolate these findings to gainunderstanding of the microbial processes responsible for the functioning of biomimicry-based watertreatment systems. Of particular interest was the potential consequence of labile nutrient availability on thedegradation of micropollutants in the treatment systems. The results showed that, while labile carbon sources(such as glucose) do affect the removal of the tested micropollutants, methylparaben and carbamazepine, thedegree of this effect is not significant enough to explain the lack of micropollutant removal. In contrast, thesetwo compounds had a significant effect on biofilm structure, even when applied at low concentrations (1000ng.L-1 and 600 ng.L-1 for methylparaben and carbamazepine, respectively), as revealed by scanning confocallaser microscopy. Microbial biofilms execute degradative functions with flexibility and are furthermore ableto efficiently adapt in a manner that humans have yet to replicate. Since our dependency on natural processessuch as bio-utilisation and bio-assistance of microbes in our constructs cannot be denied or replaced,biomimicry shows promise as a framework for the design of wastewater treatment systems that replicatenatural processes.

[发布机构] Stellenbosch University