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 | Hydroperoxy Fatty Acids Products |
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| The first stable intermediate in the oxidation of polyunsaturated fatty acids (PUFAs) is the hydroperoxy fatty acid. Cayman Chemical provides the 5-, 12-, and 15-lipoxygenase-derived hydroperoxides of arachidonic and eicosapentaenoic acids. The hydroperoxides of linoleic, linolenic acids complete this group. (Prostaglandin G2, which is a cyclo-oxygenase-derived hydroperoxide, is also available.) |
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| An essential structural element of the fatty acid for lipoxygenase catalysis is the 1,4-pentadiene. Insertion of molecular oxygen with the concomitant rearrangement of the double bond to form a 1,3-conjugated diene results in the fatty acid hydroperoxide with a chromophore that absorbs strongly around 236 nm. This chromophore and its extinction coefficient (inferred from the corresponding hydroxy acid) are used to accurately quantitate the hydroperoxide. |
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| The hydroperoxy function of these products is the most reactive and hence the most unstable part of the molecule. Hydroperoxides undergo both one electron (homolytic cleavage of the O-O bond) and two electron (heterolytic cleavage of the O-O bond) reductions in the presence of suitable reducing agents. Transition metals (iron, copper, etc.) and easily oxidizable compounds such as thiols and phenols are reducing agents that can decompose hydroperoxides. |
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| All fatty acid hydroperoxides are provided as solutions in ethanol previously purged of oxygen. Like the PUFAs and hydroxy fatty acids, hydroperoxy fatty acids are also susceptible to autoxidation. Hence, the care and use protocols suggested for fatty acids should also be applied to these hydroperoxides. Additionally, it is important to avoid making dilutions in strongly acidic or basic buffers. Because of the thermal instability of the RO-OH bond, these hydro-peroxides should seldom be warmed above 0°C before adding to incubation mixtures. The half-life for most of these hydroperoxides in aqueous solutions at room temperature is less than 10 minutes. Hydroperoxides placed into long-term storage should always be kept at -80°C. |
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| Suggestions for further reading |
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- Ingram, C.D. and Brash, A.R. Characterization of HETEs and related conjugated dienes by UV spectroscopy. Lipids 23, 340-344 (1988).
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