Organic Pollutant Migration in Soils as Affected by Soil Organic Matter. Molecular and Mechanistic Aspects

Senesi, N.

doi:10.1007/978-3-642-77862-9_3

Cited by 41 publications

(24 citation statements)

References 41 publications

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“…Thus, it is not possible to assign an exact structure to HS. Instead, they are operationally defined using a model structure predicated on available compositional, structural, functional, and behavioral data: a model structure containing all the same basic structural units and types of reactive functional groups (46). HS have been demonstrated to contain a large amount of residues resembling the original building blocks (aromatic subunits, amino acids, carbohydrates, etc.)…”

mentioning

confidence: 99%

Estimation of Uptake of Humic Substances from Different Sources by Escherichia coli Cells under Optimum and Salt Stress Conditions by Use of Tritium-Labeled Humic Materials

Куликова

Perminova

Badun

et al. 2010

Appl Environ Microbiol

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The primary goal of this paper is to demonstrate potential strengths of the use of tritium-labeled humic substances (HS) to quantify their interaction with living cells under various conditions. A novel approach was taken to study the interaction between a model microorganism and the labeled humic material. The bacterium Escherichia coli was used as a model microorganism. Salt stress was used to study interactions of HS with living cells under nonoptimum conditions. Six tritium-labeled samples of HS originating from coal, peat, and soil were examined. To quantify their interaction with E. coli cells, bioconcentration factors (BCF) were calculated and the amount of HS that penetrated into the cell interior was determined, and the liquid scintillation counting technique was used as well. The BCF values under optimum conditions varied from 0.9 to 13.1 liters kg ؊1 of cell biomass, whereas under salt stress conditions the range of corresponding values increased substantially and accounted for 0.2 to 130 liters kg ؊1 . The measured amounts of HS that penetrated into the cells were 23 to 167 mg and 25 to 465 mg HS per kg of cell biomass under optimum and salt stress conditions, respectively. This finding indicated increased penetration of HS into E. coli cells under salt stress.Humic substances (HS) are natural organic compounds comprising 50 to 90% of the organic matter of peat, coal, and sapropel (i.e., sludge that accumulates at the bottom of lakes), as well as of the nonliving organic matter of soil and water ecosystems (9,34,53). Being the products of stochastic synthesis, HS are characterized as polydispersed substances having elemental compositions that are nonstoichiometric and structures which are irregular and heterogeneous. Thus, it is not possible to assign an exact structure to HS. Instead, they are operationally defined using a model structure predicated on available compositional, structural, functional, and behavioral data: a model structure containing all the same basic structural units and types of reactive functional groups (46). HS have been demonstrated to contain a large amount of residues resembling the original building blocks (aromatic subunits, amino acids, carbohydrates, etc.) (51) as well as polyphenolic components with nonhydrolyzable C-C and ether bonds (51, 16). Since humic matter is a complex mixture of organic substances, HS yield extremely high polydispersity values (i.e., the ratio of weight-average molecular weight to the number-average molecular weight [M w /M n ]), which vary within the range of 1.64 to 4.40 (38). These extremely high polydispersity values mean that even though they yield relatively high values of molecular weight, HS contain a low-molecular-weight fraction.HS are known to play important roles in protecting microorganisms and higher plants from climatic and technogenic stresses, such as pollution, draught, UV irradiation, and pathogen and viral infections (2, 22, 31). However, mechanisms underlying protective functions of these natural systems are still poorly und...

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confidence: 99%

Estimation of Uptake of Humic Substances from Different Sources by Escherichia coli Cells under Optimum and Salt Stress Conditions by Use of Tritium-Labeled Humic Materials

Куликова

Perminova

Badun

et al. 2010

Appl Environ Microbiol

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“…In particular, HS are shown to be able to modify water solubility of organic contaminants, exert catalytic activity on some of them, act as photosensitizers in promoting their photodegradation, and, especially, adsorb them [e.g., [33][34][35][36][37]. Adsorption of contaminants onto HAs occurs through specific physical and chemical binding mechanisms, including ionic, hydrogen and covalent bonding, charge-transfer or electron donor-acceptor mechanisms, dipole-dipole and Van der Waals forces, ligand exchange, and cation and water bridging [33][34][35][36][37]. However, adsorption of nonpolar (hydrophobic) organic contaminants can be better described in terms of non-specific, hydrophobic or partitioning processes between the aqueous phase and the solid organic phase.…”

Section: The Influence Of Natural Organic Matter On Phytoremediationmentioning

confidence: 99%

Phytodecontamination of Water Systems from Phenolic Endocrine Disruptors and the Regulation Role of Natural Organic Matter

Loffredo¹,

Traversa²

2015

TOBIOTJ

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“…Humic substances absorb ultraviolet light. The molecules become excited (triplet state) in the process and transfer energy to ground state oxygen (30,) to form singulett oxygen ('O,), which, in turn may generate humic acid cation radicals (SENESI, 1993). Both clay minerals and humic substances contain Fe and Mn ions, which are able to generate oxidative coupling reactions of phenolic compounds to form humic substances (BOLLAG and LOLL, 1983).…”

Section: Models Of Humic Substancesmentioning

confidence: 99%

“…Sorption is considered as a reversible process which leads to relatively labile associations of xenobiotics with the organic matrix. Van der Waals forces, hydrogen bonds, dipole-dipole and hydrophobic interactions, electrostatic Coulomb forces (ion bonds), ligand exchange and charge transfer complexes are the forces of interaction (HASSETT and BANWART, 1989;SENESI, 1993). These forces are additive.…”

Section: Residues Within the Organic Soil Matrixmentioning

confidence: 99%

“Humification” Process or Formation of Refractory Soil Organic Matter

Kästner¹

2000

Biotechnology

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Organic Pollutant Migration in Soils as Affected by Soil Organic Matter. Molecular and Mechanistic Aspects

Cited by 41 publications

References 41 publications

Estimation of Uptake of Humic Substances from Different Sources by Escherichia coli Cells under Optimum and Salt Stress Conditions by Use of Tritium-Labeled Humic Materials

Estimation of Uptake of Humic Substances from Different Sources by Escherichia coli Cells under Optimum and Salt Stress Conditions by Use of Tritium-Labeled Humic Materials

Phytodecontamination of Water Systems from Phenolic Endocrine Disruptors and the Regulation Role of Natural Organic Matter

“Humification” Process or Formation of Refractory Soil Organic Matter

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