Xenobiotic

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Xenobiotics ( Greek for substances alien to life ) are chemical compounds that are alien to the biological cycle of an organism or natural ecosystems . They often contain structural elements that do not occur in this form, or only rarely occur in natural substances .

Origin and meaning

In nature, xenobiotics are almost always of anthropogenic origin; frequent xenobiotics are artificial pesticides , such as halogenated hydrocarbons or plastics . Many of these substances are biologically difficult or not degradable . This is partly due to the presence of functional groups that rarely occur in nature, such as aromatic nitro or sulfonic acid groups, see for example the letter acids .

Xenobiotics can have a positive, non-existent or harmful effect on the environment and organisms ( ecotoxicity ). A toxic effect depends not only on absorption (solubility in fat or water) but also on biodegradability or the possibility of making the mostly lipophilic xenobiotic water-soluble and thus excretable through biotransformation , as well as on accumulation in certain organisms or parts of organisms.

biochemistry

In biochemistry , the term xenobiotics includes all exogenous substances. When using the term, it is important to pay attention to which organism is meant. For example, a xenobiotic substance for humans such as. B. an antibiotic , not xenobiotic for the fungus that forms them.

See also

Individual evidence

  1. ↑ Entry on xenobiotic . In: IUPAC Compendium of Chemical Terminology (the “Gold Book”) . doi : 10.1351 / goldbook.XT06755 Version: 2.2.
  2. ↑ a b c Entry on xenobiotics. In: Römpp Online . Georg Thieme Verlag, accessed on May 3, 2013.
  3. ↑ Science online lexica: Entry on xenobiotics in the lexicon of biology. Retrieved May 30, 2011.

further reading

  • H. Parvez and C. Reiss: Molecular Responses to Xenobiotics . Elsevier, 2001, ISBN 0-345-42277-5 .
  • C. Ioannides: Enzyme Systems That Metabolize Drugs and Other Xenobiotics . John Wiley and Sons, 2001, ISBN 0-471-89466-4 .
  • M. Richardson: Environmental Xenobiotics . Taylor & Francis Ltd, 1996, ISBN 0-7484-0399-X .
  • C. Ioannides: Cytochromes P450: Metabolic and Toxicological Aspects . CRC Press Inc, 1996, ISBN 0-8493-9224-1 .
  • YC Awasthi: Toxicology of Glutathionine S-transferses . CRC Press Inc, 2006, ISBN 0-8493-2983-3 .