Modulation of microbial consortia enriched from different polluted environments during petroleum biodegradation

Abstract

Environmental microbial communities are key players in the bioremediation of hydrocarbon pollutants. Here we assessed changes in bacterial abundance and diversity during the degradation of Tunisian Zarzatine oil by four indigenous bacterial consortia enriched from a petroleum station soil, a refinery reservoir soil, a harbor sediment and seawater. The four consortia were found to efficiently degrade up to 92.0% of total petroleum hydrocarbons after 2 months of incubation. Illumina 16S rRNA gene sequencing revealed that the consortia enriched from soil and sediments were dominated by species belonging to Pseudomonas and Acinetobacter genera, while in the seawater-derived consortia Dietzia, Fusobacterium and Mycoplana emerged as dominant genera. We identified a number of species whose relative abundances bloomed from small to high percentages: Dietzia daqingensis in the seawater microcosms, and three OTUs classified as Acinetobacter venetianus in all two soils and sediment derived microcosms. Functional analyses on degrading genes were conducted by comparing PCR results of the degrading genes alkB, ndoB, cat23, xylA and nidA1 with inferences obtained by PICRUSt analysis of 16S amplicon data: the two data sets were partly in agreement and suggest a relationship between the catabolic genes detected and the rate of biodegradation obtained. The work provides detailed insights about the modulation of bacterial communities involved in petroleum biodegradation and can provide useful information for in situ bioremediation of oil-related pollution.

Evolution of humic acids during ex situ bioremediation on a pilot level: The added value of the microbial activity

“…The lite-826 ŽERAĐANIN et al rature shows these genera degrade petroleum and its derivatives with high efficiency. [1][2][3]5 Determination of group composition of the composite polluted biopile samples Fractional separation of organic matter extracted from composite polluted biopile samples resulted in three classes of compounds ( Fig. 3): saturated hydrocarbons, aromatic hydrocarbons, and the alcohols and ketones.…”

“…2,3 Pollution occurs 822 ŽERAĐANIN et al due to accidental releases of hazardous waste during extraction, refining, transport, storage and the use of petroleum and its derivatives. 4,5 However, the persistence of these compounds in the environment and their toxic effects can cause risks for humans and other living organisms. 1,5,6 Bioremediation is a method of remediating petroleum pollution by applying selected microorganisms to polluted environmental substrates.…”

“…4,5 However, the persistence of these compounds in the environment and their toxic effects can cause risks for humans and other living organisms. 1,5,6 Bioremediation is a method of remediating petroleum pollution by applying selected microorganisms to polluted environmental substrates. These non-pathogenic microbes can degrade or transform toxic substances into harmless products.…”

Vertical stratification of bacteria and the chemical compounds in crude oil-contaminated soil layers of the semi-deserted Dzungharian Basin

“…Bioremediation has emerged in recent years as a prospective measure to counteract these pollutants. During the bioremediation process, engineering measures such as selectively inoculating the bacteria agency and feeding bacteria with nutrients were generally used to accelerate the decomposition and demineralization of organic matter by improving the catabolism of microorganisms [ 5 – 7 ]. However, in most of the cases, especially those in deserted areas, the degradation of contaminants was still a natural attenuation process, depending on the hydrocarbon-utilizing microorganisms inhabiting the local ecosystems.…”

“…Resolution of the microbial communities in the contaminated sites has enriched our understanding of the magnitude of the diversity, richness, distribution and dynamics of the microbial communities in polluted sites, and it has also facilitated the selective inoculation of bacterial agents into the polluted sites to significantly improve the efficiency of bioremediation. At present, the microbial community compositions in ecological environments such as crude oil-contaminated soils [ 7 , 8 ], marine sediments [ 9 , 10 ], etc. are being gradually resolved using phylogenetic and gene-targeted tools.…”