Survival and catabolic performance of introducedPseudomonasstrains during phytoremediation and bioaugmentation field experiment

Abstract

A long-term field experiment was carried out to estimate the efficiency of bioaugmentation in combination with phytoremediation for oil shale chemical industry solid waste dump area remediation. Soil samples for microbiological and chemical analysis were collected during 3 years after bacterial biomass application. Microbial communities in soil samples were analysed using both culture-based and molecular methods. The survival of the introduced bacterial strains was confirmed by cultivation-based Box-PCR genomic fingerprints and denaturing gradient gel electrophoresis fingerprinting of the 16S rRNA and lmPH genes. The introduced bacterial strains as well as corresponding catabolic genes were recovered several years after biomass application, predominantly from the rhizosphere of birches. Soil samples from bioaugmented plots showed an elevated potential for degradation of phenolic compounds even 40 months after treatment. Based on our results we can conclude that the introduced Pseudomonas strains both survived, and their metabolic traits have persisted at the contaminated site over a long period of time.

Enhanced polychlorinated biphenyl removal in a switchgrass rhizosphere by bioaugmentation with Burkholderia xenovorans LB400

“…An accumulation of ITSs was observed throughout the 24 week experiment, suggesting that after each bioaugmentation, a percentage of LB400 adapted to the soil environment and survived alongside indigenous microorganisms (Figure 5). The support of plants to bioaugmentation has been reported (Juhanson et al, 2009; Secher et al, 2013; Tam and Wong, 2008). Switchgrass facilitated LB400 survival possibly by improving aeration and providing root exudates as carbon and energy sources.…”

Soil type affects plant colonization, activity and catabolic gene expression of inoculated bacterial strains during phytoremediation of diesel

“…gene expression has been rarely addressed [31,36]. However, for efficient degradation not only the abundance of plantassociated bacteria and/or applied inoculants strains but also the degrading activity is highly important [37]. Characteristics of the soil environment such as soil organic matter or particle sizes may influence the colonization process but may also have pronounced influence on the expression of degrading genes.…”

Nutrients Can Enhance the Abundance and Expression of Alkane Hydroxylase CYP153 Gene in the Rhizosphere of Ryegrass Planted in Hydrocarbon-Polluted Soil

“…Therefore, it is important to analyze the levels of abundance and expression of pollutant-degrading genes in the contaminated soil during phytoremediation [14].…”