Abstract
The conversion of lipophilic, non-polar foreign compound to hydrophilic, polar species is essential to facilitate their excretion from the body. The conversion processes occur in two separate metabolic steps: functionalization reactions catalyzed by activation enzymes such as cytochrome P450s and conjugation reactions catalyzed by detoxification enzymes such as transferases. A polar group is introduced to a foreign compound in the functionalization reaction, thus increasing the water solubility of the parent compound. During functionalization reactions, some foreign compounds may form reactive intermediate species or metabolites, which can play an essential role in the pathogenesis of many disease conditions. Detoxification enzyme-catalyzed reactions modify foreign compounds to make them less toxic and more soluble in water and thus facilitate them to excrete from the body. Defenses against reactive intermediate species or metabolites generated from bioactivation include detoxification enzymes and antioxidants.
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16 June 2020
After initial publication of the book, various errors were identified that needed correction. All corrections listed below have been updated within the current version.
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Chen, CH. (2020). Metabolisms of Foreign Compounds. In: Xenobiotic Metabolic Enzymes: Bioactivation and Antioxidant Defense. Springer, Cham. https://doi.org/10.1007/978-3-030-41679-9_4
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DOI: https://doi.org/10.1007/978-3-030-41679-9_4
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