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| Titel |
Chemical properties of peat used in balneology |
| VerfasserIn |
L. Szajdak, T. Hładoń |
| Konferenz |
EGU General Assembly 2009
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 11 (2009) |
| Datensatznummer |
250021993
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| Zusammenfassung |
| The physiological activity of peats is observed in human peat-bath therapy and in the
promotion of growth in some plants. Balneological peat as an ecologically clean and natural
substance is perceived as being more ‘human friendly’ than synthetic compounds. Poland has
a long tradition of using balneological peat for therapeutic purposes. Balneological peat
reveals a physical effect by altering temperature and biochemical effects through biologically
active substances. It is mainly used for the treatment of rheumatic diseases that are quite
common in Poland.
Peat represents natural product. Physico-chemical properties of peat in particular
surface-active, sorption and ion exchanges, defining their biological function, depend mainly
on the chemical composition and molecular structure of humic substances representing the
major constituent of organic soil (peat). The carbon of organic matter of peats is composed of
10 to 20% carbohydrates, primarily of microbial origin; 20% nitrogen-containing
constituents, such as amino acids and amino sugars; 10 to 20% aliphatic fatty acids, alkanes,
etc.; with the rest of carbon being aromatic.
For balneology peat should be highly decomposed (preferably H8), natural and clean. The
content of humic acids should exceed 20% of dry weight, ash content will be less
than 15 15% of dry weight, sulphur content less than 0.3% of dry weight and the
amount of water more than 85%. It will not contain harmful bacteria and heavy
metals.
Humic substances (HS) of peat are known to be macromolecular polydisperse biphyllic
systems including both hydrophobic domains (saturated hydrocarbon chains, aromatic
structural units) and hydrophilic functional groups, i. e having amphiphilic character.
Amphiphilic properties of FA are responsible for their solubility, viscosity, conformation,
surfactant-like character and a variety of physicochemical properties of considerable
biologically practical significance.
The chemical composition of peats depends significantly on the genesis of peatlands and
the depth of sampling. The chemical properties of peat fulvic acids (FA) have some genetic
peculiarities due to the specific conditions of the process of humification of peat-forming
plants in mires. The process of humification in mires takes place in the top-forming layer
under amphibious moisture conditions. Substances of microbial origin are water-soluble and
can participate in the formation of peat FA to a little extent. So a main source of
structural units for the peat HA and FA is suggested to be organic constituents of peat
forming plants of various botanical composition. The content of aromatic units in
peat FA was shown to depend on the content of lignin in peat-forming plants and
also of the aromatization of polysaccharides mainly due to the transformation of
cellulose.
FA characterized lower than humic acids molecular weight (1000-30,000). FA’s are
composed of a series of highly oxidized aromatic rings with a large number of side
chains. Building blocks are benzene carboxylic acids and phenolic acids. These are
held together by hydrogen bonding van der Waals’ forces and ionic bonding. FA
contains larger concentrations of nitrogen. This fraction also contains a great deal of
polysaccharide materials, as well as low molecular fatty acids and cytoplasmic
constituents of microorganisms. These compounds are linear, flexible colloids at low
concentrations, and spherical colloids at high solution concentrations and low pH
values.
A more adequate knowledge of the chemical structure of humic materials will
assist us in better understanding the physiological effects and also the function of
these macromolecules on the health that these materials are know to exert. This
improved knowledge provides us better information on chemical structure of humic
substances from peats, which are responsible for pharmacotherapeutic, pharmacokinetic
and biopharmaceutical effect. This structure of FA creates proper conditions for
uptake of nutrient as well as bioavailability of biologically active substances. The
solubilization in water by humic materials of organic substances which are otherwise
water-insoluble is a matter of considerable interest to chemist deals with the problem of
the function of organic matter. There has been considerable evidence that humic
substances can “complex” with several biologically active substances and so modify their
physiological activity. It has been noteworthy that FA can “fix” high-molecular weight
water-insoluble organic compounds and make them water-soluble. FA may so act as a
vehicle for the mobilization, transport and immobilization of such substances in
physiological conditions. Analysis of HA and FA carried out by several analytical
methods revealed that there were no chemical interaction among biologically active
substances but that latter was firmly adsorbed, possible by hydrogen-bonding, on the FA
surfaces.
Amino acids account for the majority of organic N fraction in humic substances. Most of
the amino acids in organic matter occur in bound form in the humino-peptides fraction. These
amino acids are commonly bound to the central core of FA. These humino-peptides fraction
of FA mediate in respiration and act as hydrogen acceptors, thus affecting oxidation-reaction
reactions.
Thus, what is needed at this time is more fundamental research in order to solve practical
pharmacological, pharmacokinetic and biopharmaceutical problem of great significance for
human health. |
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