The reaction stoichiometry between ozone and unsaturated fatty acids in an aqueous environment

✍ Scribed by Robert L. Heath

• Publisher: Elsevier Science
• Year: 1978
• Tongue: English
• Weight: 632 KB
• Volume: 22
• Category: Article
• ISSN: 0009-3084
• DOI: 10.1016/0009-3084(78)90004-x

✦ Synopsis

The light absorption of ozone in an air stream allowed the monitoring of reactions of ozone with unsaturated fatty acids in solution. The ldnetics for the reaction of ozone with linolenic acid was found to be of a pseudo-first-order after the f'trst few minutes and did not vary with the concentration of ozone introduced into the solution. The reaction of ozone with linolenic acid in solution was found to be exceedingly rapid.

When various combinations of polyunsaturated fatty acids were injected simultaneously, they reacted independently. The stoichiometry of ozone reacted to number of double bonds present in the fatty acid was one for mono-and diunsaturated; however, for triunsaturated fatty acid the stoichiometry was about 0.70.

Malondialdehyde was produced upon the reaction of ozone with di-and triunsaturated fatty acids, as shown by both the thiobarbituric acid test and the characteristic UV absorption of malondialdehyde in solution. The true yield of malorrl!n_ldehyde for the reaction of polyunsaturated fatty acids with ozone was found to be about 2%. In addition, other species, absorbing at 290-300 nm, were formed in solution during ozonolysis. * Time after injection of linolenic acid (110 pM). ** UV assayas described in Methods , corrected for blank at 30 sec. *** TBA assay as described in Methods [9], corrected for blank at 30 sec.

§ The test volume for TBA test at this point was changed, using only 0.1 ml sample + 0.9 ml Tris, rather than 0.5 ml sample + 0~S ml Tris for the test.