Lead Removal from Contaminated Water by a Mixed Microbial Ecosystem

Abstract

The research reported here explored the advantages of using an integrated ecosystem for the uptake of lead and examined some of the possible mechanisms for the transfer of the metal through the system with eventual binding in the microbial biomass. Strategies were applied to (1) stimulate enhanced production of biomass and consequent lead recovery by simple enrichments of the microbial environment, and (2) increase the microbial tolerance and lead uptake capacity by adaptation of the component species. The microbial ecosystem employed here was one which arose spontaneously after pond enrichment with silaged grass clippings and moved through a predictable microbial succession. Ecosystem processes and microbial relationships resulted in the mobilization of metal in the soil bed and water column with ultimate deposition in the surface biomass. The stable silage-microbe biomass, floating at the top of the pond, bound the metal for extended periods of time.

Treatment of Mine Water by a Microbial Mat: Bench-scale Experiments

“…Microbial mats have been used experimentally in the U.S. to treat mine water containing metals and other pollutants (Bender et al 1989;Bender et al 1991;Bender 1992;Bender 1993;). have developed microbial mats with specific microbial components for a variety of bioremediation.…”

Comparative yields of T-2 toxin and related trichothecenes from five toxicologically important strains of Fusarium sporotrichioides

“…Mixed microbial communities, or mats, were developed for bioremediation by stimulating the formation of a microbial consortium with specific substrates (ensiled grass) and inocula composed of Oscillatoria sp. and purple bacteria (identification in progress) and allowing volunteer heterotrophic groups from the soil bed to colonize the preparation along with the photosynthetic species (2,5). The resulting mats were used for the bioflocculant research described below.…”

“…nated by an Oscillatoria sp. were effective in removing Pb, Cd, Cu, Zn, Co, Cr, Fe, and Mn from water (2)(3)(4)6). Although the mechanisms of metal removal are complex, the production of bioflocculants by cyanobacteria may be central to the initial detoxification of metal-contaminated media by these organisms.…”

Removal of zinc and manganese from contaminated water with cyanobacteria mats

“…Figure 1 illustrates the zones associated with a synthetic cyanobacteria mat formed around the ensiled grass. The laminated structure of the mat creates discrete zones of unique chemistry characterized by oxic and anoxic regions in close proximity (Bender et al, 1989b). Metal-tolerant cyanobacteria strains (Oscillatoria spp.)…”

“…These mats effectively sequestered heavy metals and sometimes transformed metalloids in laboratory ponds. (Bender et al, 1989b;Bender et al, 1991).…”