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Mixed Function Oxygenase Induction by Pulp Mill Effluents: Advances Since 1991
Published in Mark R. Servos, Kelly R. Munkittrick, John H. Carey, Glen J. Van Der Kraak, and PAPER MILL EFFLUENTS, 2020
The simultaneous association of BKME inducers with particulates, humates, and the aqueous phase indicates compounds with a low water solubility; above saturation, “excess” inducers become absorbed to DOC and to particles. This absorbed material is not readily soluble in solvents such as pentane, dichloromethane, and acetone (Burnison et al. 1994), indicating that inducers are not highly hydrophobic, as would be typical of chlorinated dioxins and furans. Methanol solubility suggests compounds of intermediate polarity, although solubility occurs only at concentrations above 80%. This property allows the separation of inducers from other compounds by reverse phase HPLC. Using isocratic elution with 80% methanol, followed by a column wash with 100% methanol, Burnison et al. (1994) found that MFO inducers consistently eluted with marker compounds having log octanol-water partition coefficients (Kow) of about 4.5-5.1, somewhat less than would be typical of PCBs, dioxins, and furans. Peaks shown by fluorometric detection included phenanthrene and substituted phenanthrenes.
Fungal Influence on Hydrophobic Organic Pollutants Dynamics within the Soil Matrices
Published in Vivek Kumar, Rhizomicrobiome Dynamics in Bioremediation, 2021
Claire Baranger, Isabelle Pezron, Anne Le Goff, Antoine Fayeulle
Remediation enhancement in presence of surfactant is likely driven by two main mechanisms involving i) solubilization and transport of organic compounds into micelles, and ii) displacement of entrapped NAPLs due to interfacial tension reduction (Paria 2008). Indeed, when in presence of surfactant, the fraction of HOC found in micellar form is directly available for degrading bacteria, in a similar way to the dissolved fraction of HOC (Brown 2007). Biosurfactant-enhanced desorption of phenanthrene from suspended clays and humic acid was observed by Garcia-Junco (Garcia-Junco et al. 2003). Similar mechanisms may be involved for fungal surfactants, increasing the bioavailability of HOC in soils to both the fungus itself and other microorganisms.
Bioaugmentation in the Bioremediation of the Heavy Metals and Radionuclides
Published in Inamuddin, Charles Oluwaseun Adetunji, Mohd Imran Ahamed, Tariq Altalhi, Bioaugmentation Techniques and Applications in Remediation, 2022
Bhagwan Toksha, Saurabh Tayde, Ajinkya Satdive, Shyam Tonde, Aniruddha Chatterjee
It consists of air stimulation by incorporating oxygen to the unsaturated portion of the polluted site under controlled conditions. Delivery of oxygen under controlled conditions improves bioremediation rate through increased microbial activities. The rate of bioremediation can be stimulated by the incorporation of nutrients and moisture at the contaminated site. This is a widely used technique as compared to the other in situ technology (Philp and Atlas 2005; Höhener and Ponsin 2014). Frutos et al. (2010) investigated that the use of bioventing in remediation of soil contaminated with phenanthrene has removed about 93% of the contaminants after 7 months.
Phylogeny and polycyclic aromatic hydrocarbons degradation potential of bacteria isolated from crude oil-contaminated soil in Diyarbakir, in the southeast of Turkey
Published in Bioremediation Journal, 2021
Polycyclic Aromatic Hydrocarbons (PAHs), which are comprised of two or more fused benzene rings, are environmental contaminants that occur through both natural and anthropogenic processes and are commonly found worldwide in soils and sediments (Yu et al. 2005; Hilyard et al. 2008; Wang et al. 2019). PAHs cause major environmental concern due to their toxicity, mutagenicity, carcinogenicity, resistance properties, bioaccumulation potential and low water solubility (Guo et al. 2005; Haritash and Kaushik 2009; Ma et al. 2011). Because of these properties, the European Union and the United States Environmental Protection Agency have identified approximately 16 PAHs as priority pollutants and their concentrations have been controlled and regulated for a variety of matrices. Therefore, their environmental destinies attract a great deal of attention from researchers (Ma et al. 2011; Rabodonirina et al. 2019). Among PAHs, phenanthrene, which is a major constituent of coal derivatives and oil fuels, is a highly reactive three-ring compound that is commonly found in polluted sites among PAHs. Since it is the smallest PAH with a sterically hindered bay-region and a K-region in the molecule, phenanthrene, is often used as a model compound to research PAH metabolism by microbial communities (Thomas et al. 2016; Chebbi et al. 2017).
Modified silica gels as recyclable adsorbents of aqueous polycyclic aromatic hydrocarbons
Published in Green Chemistry Letters and Reviews, 2019
John Regan, Jessi Dolores, Megan Lepore, Michael Gualano, Jeovanna Badson, Amanda Zimnoch, Joseph F. Capitani, Jianwei Fan
Phenanthrene is used as a prototypical compound for the removal of PAH molecules from aqueous solutions. It has strong fluorescence in the UV region (λex =251 nm and λem = 365 nm), therefore, its aqueous concentration is monitored by fluorescence intensity. When exposed to the reverse phase silica gels in a stirring environment the fluorescence intensity of phenanthrene rapidly decreases indicating the adsorption of phenanthrene onto the lipophilic domains of the silica gel. As shown in Figure 6 the silica gel coated with cyclopentyl(phenyl)acetic acid reaches saturation between 3 and 4 h. This is generally within the time frames of rapid adsorbing materials, which include waste ion exchange resin (20), periodic mesporous organosilica (21) and granulated activated carbon (22, 23), and slower adsorbing substances such as activated carbon (24)
Cement-Organobentonite Admixtures for Stabilization/Solidification of PAH-Contaminated Soil: A Laboratory Study
Published in Soil and Sediment Contamination: An International Journal, 2019
Mohammad Ghavami, Daryoush Yousefi Kebria, Sadra Javadi, Omid Ghasemi-Fare
Two PAHs, naphthalene and phenanthrene, were chosen because of their widespread presence in contaminated soil and non-aqueous phase liquids (NAPLs). Naphthalene is the simplest PAH and it can be found in a various range of products, such as petroleum products, mothballs, solvents, dyes and wood preservatives, and can be released into the environmental systems. Phenanthrene is another type of PAH, and it is composed of three fused benzene rings with a chemical formula of C14H10. Phenanthrene has been widely used in the synthesis of dyes, explosives and drugs. The EPA classifies naphthalene and phenanthrene as possibly carcinogenic to humans and animals. Naphthalene and phenanthrene are barley soluble in water. However, both can be soluble in most low-polarity organic solvents including acetic acid, toluene, ether, heptane, etc.