biodegradation of polycyclic aromatic hydrocarbons, toxic compounds widely distributed in the environment by bacteria, is a cheap and safe cleaning up method. the present study attempts to isolate and characterize dioxygenase-producing bacteria which are able to degrade phenanthrene and pyrene from refinery soils. it also aims to assess in vitro biodegradation. to do so, two contaminated soil s...

Cyclopenta(cd)pyrene, a constituent of environmental emissions, has been found to mutate and transform mammalian cells in culture. Cyclopenta(cd)pyrene 3,4-oxide, a presumed metabolite, was found to be a direct-acting mutagen and to transform mammalian cells. These results suggest that cyclopenta(cd)pyrene 3,4-oxide may be an ultimate mutagenic form of the parent hydrocarbon.

pyrene and tran8-4,5-dihydro-4,5-dihydroxypyrene, were present in the bile of rats treated with pyrene. 3. In the oxidation of pyrene with perbenzoic acid an intermediate was formed, believed to be 4,5-epoxy-4,5-dihydropyrene, which reacted with water to yield tran8-4,5-dihydro-4,5-dihydroxypyrene and with N-acetyl-L-cysteine to form Nacetyl-S-(4,5-dihydro-4-hydroxy-5-pyrenyl)-L-CySteine. 1-Hyd...

One- and two-dimensional nuclear magnetic resonance (NMR) experiments were performed on Agave americana cutan and tomato cutin to examine the interactions between a hydrophobic pollutant, pyrene, and cuticular material. Variable-temperature NMR experiments show that cutan, an acid- and base-resistant cuticular biopolymer, undergoes the characteristic melting behavior of "polyethylene-like" crys...

CYP1A1 and CYP1B1 metabolically activate many polycyclic aromatic hydrocarbons (PAHs), including benzo[a]pyrene, to reactive intermediates associated with toxicity, mutagenesis, and carcinogenesis. Paradoxically, however, Cyp1a1-/- knockout mice are more sensitive to oral benzo[a]pyrene exposure, compared with wild-type Cyp1a1+/+ mice (Mol Pharmacol 65:1225, 2004). To further investigate the me...

The location of pyrene in sodium dodecyl sulfate (SDS) micelles is determined as a function of the aggregation number, N, by exploiting the fact that spin probes 5- and 16-doxyl stearic acid methyl esters (5DSE and 16DSE, respectively) are effective quenchers of pyrene fluorescence. The locations of the two spin probes are known from Part 1 of this series (J. Phys. Chem. B 2006, 110, 9791) and ...

The effects of loading and aging pyrene in soils in the presence of four environmentally common nonaqueous-phase liquids (NAPLs) (hexadecane, 2,2,4,4,6,8,8-heptamethylnonane [HMN], toluene, and dimethyl phthalate [DMP]) on its subsequent desorption from those soils, earthworm accumulation, biodegradation, and extractability were tested by using two dissimilar soils. The presence of each of the ...

The galleries of an anionic clay, Mg-Al Layered Double Hydroxide (Mg-Al LDH) have been functionalized by intercalating the anionic surfactant do-decyl sulfate. Within the galleries, the alkyl chains of the surfactant adopt a bilayer structure with the sulfate headgroup anchored to the inorganic sheet. Pyrene molecules have been solubilized in the anchored bilayer by partitioning from polar solv...

The biodegradation of polycyclic aromatic hydrocarbon pollutants is constrained, in part, by their solid physical state and very low water solubility. Searching for ways to overcome these limitations, we isolated from soil a bacterium capable of growing on pyrene as a sole source of carbon and energy. Acid-fast stain, morphology, and fatty acid profile identified it as a Mycobacterium sp. In a ...

Microbiological analyses of sediments located near a point source for petrogenic chemicals resulted in the isolation of a pyrene-mineralizing bacterium. This isolate was identified as a Mycobacterium sp. on the basis of its cellular and colony morphology, gram-positive and strong acid-fast reactions, diagnostic biochemical tests, 66.6% G + C content of the DNA, and high-molecular-weight mycolic...