<abstract xmlns="http://www.w3.org/1999/xhtml"><p>In this paper the influence of humic acid concentrations extracted from Histosols (HA-A) and their model forms (HA-B) separated from humic substances commercially produced by Carl Roth GmbH + Co.KG on the dynamic properties of liposome membranes was determined. Differences in the quality of the humic acids (HA-A and HA-B) were determined by the <sup>1</sup>HNMR and FTIR methods. Liposomes from the sonication of egg yolk lecithin (EYL) in an aqueous solution and synthetic Dipalmitoylphosphatidylcholine (DPPC) were used. Fluidity of liposome membranes was determined by the EPR technique with spin probes (TEMPO, 16DOIXYL). The electrical parameters of membranes were found using a Keithley 6517 electrometer. Our study showed significant differences in the influence of HA-A and HA-B on the membranes. In the bilayer membranes of the liposomes of HA-A admixture there was slightly more stiffening of the interior of the membrane in comparison to HA-B. A similar effect was observed in the surface layer of the liposome membranes. This difference is particularly evident for DPPC liposomes, however, the EYL liposomes admixture with HA-B slightly increased the fluidity of the surface layer. Electrical study confirmed this effect. The study shows that natural and model forms of humic acids differ in their effects on the activity of tested membrane models. The strong differences in the interaction of HA-A and HA-B on parameter F in DPPC liposomes can be result from the transport of humic acids connected to the metal ions inside the membranes (xenobiotics present in the environment).</p></abstract>

In this paper the influence of humic acid concentrations extracted from Histosols (HA-A) and their model forms (HA-B) separated from humic substances commercially produced by Carl Roth GmbH + Co.KG on the dynamic properties of liposome membranes was determined. Differences in the quality of the humic acids (HA-A and HA-B) were determined by the 1HNMR and FTIR methods. Liposomes from the sonication of egg yolk lecithin (EYL) in an aqueous solution and synthetic Dipalmitoylphosphatidylcholine (DPPC) were used. Fluidity of liposome membranes was determined by the EPR technique with spin probes (TEMPO, 16DOIXYL). The electrical parameters of membranes were found using a Keithley 6517 electrometer. Our study showed significant differences in the influence of HA-A and HA-B on the membranes. In the bilayer membranes of the liposomes of HA-A admixture there was slightly more stiffening of the interior of the membrane in comparison to HA-B. A similar effect was observed in the surface layer of the liposome membranes. This difference is particularly evident for DPPC liposomes, however, the EYL liposomes admixture with HA-B slightly increased the fluidity of the surface layer. Electrical study confirmed this effect. The study shows that natural and model forms of humic acids differ in their effects on the activity of tested membrane models. The strong differences in the interaction of HA-A and HA-B on parameter F in DPPC liposomes can be result from the transport of humic acids connected to the metal ions inside the membranes (xenobiotics present in the environment).

The Influence of Natural and Model Forms of Humic Acids on the Dynamic Parameters of Model Membranes

Pedology Team, Department of Land Protection, University of Opole, ul. Oleska 22, 45-052 Opole,

Biophysical Team, Institute of Physics, University of Opole, ul. Oleska 48, 45-052 Opole,

Embryology Laboratory, Medical Center „Antrum”, ul. Olimpijska 5, 41-902 Bytom,

Ecological Chemistry and Engineering S

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

In this paper the influence of humic acid concentrations extracted from Histosols (HA-A) and their model forms (HA-B) separated from humic substances...

The Influence of Natural and Model Forms of Humic Acids on the Dynamic Parameters of Model Membranes

Published Online: Dec 30, 2016

Page range: 695 - 708

DOI: https://doi.org/10.1515/eces-2016-0049

Keywords
lecithin liposomes, ESR, HNMR, humic acid, spin label

© 2016 Izabella Pisarek et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The Influence of Natural and Model Forms of Humic Acids on the Dynamic Parameters of Model Membranes

Published Online: Dec 30, 2016

Page range: 695 - 708

DOI: https://doi.org/10.1515/eces-2016-0049

Keywordslecithin liposomes, ESR, HNMR, humic acid, spin label

© 2016 Izabella Pisarek et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
lecithin liposomes, ESR, HNMR, humic acid, spin label