Impact of Inoculation Protocols, Salinity, and pH on the Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) and Survival of PAH-Degrading Bacteria Introduced into Soil

1998 ◽  
Vol 64 (1) ◽  
pp. 359-362 ◽  
Author(s):  
Matthias Kästner ◽  
Maren Breuer-Jammali ◽  
Bernd Mahro

ABSTRACT Degradation of polycyclic aromatic hydrocarbons (PAHs) and survival of bacteria in soil was investigated by applying different inoculation protocols. The soil was inoculated with Sphingomonas paucimobilis BA 2 and strain BP 9, which are able to degrade anthracene and pyrene, respectively. CFU of soil bacteria and of the introduced bacteria were monitored in native and sterilized soil at different pHs. Introduction with mineral medium inhibited PAH degradation by the autochthonous microflora and by the strains tested. After introduction with water (without increase of the pore water salinity), no inhibition of the autochthonous microflora was observed and both strains exhibited PAH degradation.

1991 ◽  
Vol 37 (12) ◽  
pp. 924-932 ◽  
Author(s):  
J. M. Foght ◽  
D. W. S. Westlake

Forty-three bacterial strains were collected from various environmental and commercial sources and their ability to degrade polycyclic aromatic hydrocarbons (PAHs) was confirmed using the criteria of growth, mineralization, and oxidation. Undigested genomic DNA from these strains was blotted by Southern transfer to replicate membranes, which were probed either with purified plasmids (e.g., TOL and NAH7, associated with toluene and naphthalene degradation, respectively) or with genomic DNA from the other strains. The isolates were grouped according to hybridization and PAH-degradation results. One group of eight strains grew on naphthalene vapors as sole carbon source and hybridized with archetypical NAH plasmids. Another group of six isolates mineralized phenanthrene but could not grow on naphthalene, and their cryptic plasmids hybridized with Pseudomonas sp. HL7b, which degrades a wide range of PAHs. The remaining isolates, which could not grow on naphthalene but mineralized and (or) oxidized a variety of PAHs, hybridized with neither the pure plasmids nor heterologous genomic DNA, implying that their PAH-degradative genes were significantly dissimilar. This suggests that using TOL or NAH plasmids to probe an environmental population might reveal toluene- or naphthalene-degradative genes but would underestimate the occurrence of PAH-degradative genes. We suggest that a suite of probes would be necessary to evaluate the PAH-degradation potential of a mixed population. Key words: polycyclic aromatic hydrocarbons, degradative plasmids, NAH plasmid, TOL plasmid, hybridization.


2015 ◽  
Vol 101 (1) ◽  
pp. 296-303 ◽  
Author(s):  
Susann-Cathrin Lang ◽  
Andrew Hursthouse ◽  
Philipp Mayer ◽  
Danjiela Kötke ◽  
Ines Hand ◽  
...  

2019 ◽  
Vol 10 (4) ◽  
pp. 3789-3795 ◽  
Author(s):  
Neeta Bhagat ◽  
Pranita Roy ◽  
Sohini Singh ◽  
Tanu Allen

Increasing soil pollution all over the world has instigated global concerns as enormous quantities of toxic chemicals and heavy metals like cadmium, lead, mercury, petrochemicals, insecticides, polycyclic aromatic hydrocarbons (PAHs) and chlorophenols are finding their way into the environment, affecting the land and soil, causing soil pollution and thus posing a threat and menace to health and well- being of people and ecosystem. The ubiquitous dissemination, low bioavailability, high perseverance of contaminants like poly-hydrocarbon and metals in soil have the potentially destructive effects to human health, envisages to study the biodegradation of PAHs (polycyclic aromatic hydrocarbons) and PACs (polycyclic aromatic compounds). The diversity of micro-organisms that diminish the PAHs/PACs can be utilized in the advancement of bioremediation techniques. The role of metal-tolerant, (PAH)-degrading bacteria helps in the biodegradation of organic compounds at miscellaneous polluted sites. The isolation of (PAHs)-degrading bacteria from contaminated soil samples collected from garages and petrol pumps of Delhi and NCR region was carried out in the present study.  Also, the bacterial samples were tested for the tolerance towards 4 heavy metals- arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg). Morphological studies and biochemical tests were conducted to find the genera of the bacterial samples. The study indicates that hydrocarbons were degraded by the isolates P1, P2, P4, P5, P5*, G1, G3. These isolates were also found to be tolerant at a high concentration of metals (Arsenic, Cadmium, Mercury, and Lead) as minimum inhibitory concentration (MIC) was also calculated. Antibiotic susceptibility of the isolates was tested against various antibiotics. Thus the study suggests that the isolates identified as Pseudomonas aeruginosa, Acinetobacter baumanii, and Klebsiella pneumoniae are not only PAH-degrading but metal-tolerant and antibiotic-resistant too and are of immense potential for bioremediation of contaminated soils.


2003 ◽  
Vol 69 (1) ◽  
pp. 275-284 ◽  
Author(s):  
Mikael Eriksson ◽  
Erik Sodersten ◽  
Zhongtang Yu ◽  
Gunnel Dalhammar ◽  
William W. Mohn

ABSTRACT Thepotential for biodegradation of polycyclic aromatic hydrocarbons (PAHs)at low temperature and under anaerobic conditions is not wellunderstood, but such biodegradation would be very useful forremediation of polluted sites. Biodegradation of a mixture of 11different PAHs with two to five aromatic rings, each at a concentrationof 10 μg/ml, was studied in enrichment cultures inoculated withsamples of four northern soils. Under aerobic conditions, lowtemperature severely limited PAH biodegradation. After 90 days, aerobiccultures at 20°C removed 52 to 88% of the PAHs. The mostextensive PAH degradation under aerobic conditions at 7°C,53% removal, occurred in a culture from creosote-contaminatedsoil. Low temperature did not substantially limit PAH biodegradationunder nitrate-reducing conditions. Under nitrate-reducing conditions,naphthalene, 2-methylnaphthalene, fluorene, and phenanthrene weredegraded. The most extensive PAH degradation under nitrate-reducingconditions at 7°C, 39% removal, occurred in a culturefrom fuel-contaminated Arctic soil. In separate transfer cultures fromthe above Arctic soil, incubated anaerobically at 7°C, removalof 2-methylnaphthalene and fluorene was stoichiometrically coupled tonitrate removal. Ribosomal intergenic spacer analysis suggested thatenrichment resulted in a few predominant bacterial populations,including members of the genera Acidovorax,Bordetella, Pseudomonas, Sphingomonas, andVariovorax. Predominant populations from different soils oftenincluded phylotypes with nearly identical partial 16S rRNA genesequences (i.e., same genus) but never included phylotypes withidentical ribosomal intergenic spacers (i.e., different species orsubspecies). The composition of the enriched communities appeared to bemore affected by presence of oxygen, than by temperature or source oftheinoculum.


2021 ◽  
Author(s):  
Xiaohua Ma ◽  
Hao Yang ◽  
Changchun Huang ◽  
Tao Huang ◽  
Shuaidong Li

Abstract In this study, the sedimentary records, sources, and ecological risks of polycyclic aromatic hydrocarbons (PAHs) in Dianchi Lake were analyzed. The concentration ranges of ΣPAH16 in the sediments of Dianchi Lake were 368–990 ng/g, with an average value of 572 ng/g, peaking in 1988. Economic development and rapid population growth, as well as the rapid growth of coal consumption, have a greater impact on the HMW PAHs than on the LMW PAHs in the sedimentary environment. The results of the diagnostic ratios and PCA model show that the main sources of PAHs were coal and biomass combustion, as well as fossil fuel combustion sources in individual years. The risk assessment results showed that the PAH concentrations in the sediment were within a safe range. In the past 100 years of sediment pore water, except for Phe, which reached chronic toxic pollution levels in some years, other 2-3 ring LMW PAHs have been within a safe range. With the development of industrialization and urbanization, the burning of fossil fuels such as coal and petroleum has increased, and some of the 4-6 ring HMW PAHs have reached chronic toxicity or even acute toxicity in the sediment pore water.


1998 ◽  
Vol 44 (8) ◽  
pp. 743-752 ◽  
Author(s):  
Michael D Aitken ◽  
William T Stringfellow ◽  
Robert D Nagel ◽  
Chikoma Kazunga ◽  
Shu-Hwa Chen

Ten bacterial strains were isolated from seven contaminated soils by enrichment with phenanthrene as the sole carbon source. These isolates and another phenanthrene-degrading strain were examined for various characteristics related to phenanthrene degradation and their ability to metabolize 12 other polycyclic aromatic hydrocarbons (PAH), ranging in size from two to five rings, after growth in the presence of phenanthrene. Fatty acid methyl ester analysis indicated that at least five genera (Agrobacterium, Bacillus, Burkholderia, Pseudomonas, and Sphingomonas) and at least three species of Pseudomonas were represented in this collection. All of the strains oxidized phenanthrene according to Michaelis-Menten kinetics, with half-saturation coefficients well below the aqueous solubility of phenanthrene in all cases. All but one of the strains oxidized 1-hydroxy-2-naphthoate following growth on phenanthrene, and all oxidized at least one downstream intermediate from either or both of the known phenanthrene degradation pathways. All of the isolates could metabolize (oxidize, mineralize, or remove from solution) a broad range of PAH, although the exact range and extent of metabolism for a given substrate were unique to the particular isolate. Benz[a]anthracene, chrysene, and benzo[a]pyrene were each mineralized by eight of the strains, while pyrene was not mineralized by any. Pyrene was, however, removed from solution by all of the isolates, and the presence of at least one significant metabolite from pyrene was observed by radiochromatography for the five strains in which such metabolites were sought. Our results support earlier indications that the mineralization of pyrene by bacteria may require unique metabolic capabilities that do not appear to overlap with the determinants for mineralization of phenanthrene or other high molecular weight PAH.Key words: kinetics, polycyclic aromatic hydrocarbons, phenanthrene, mineralization, benzo[a]pyrene.


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