Micelle and acid-soap formation of linoleic acid and 13-L-hydroperoxylinoleic acid being substrates of lipoxygenase-1.

Surface tension measurements of linoleic acid solutions in 0.1 M sodiumborate buffer pH 10 at 23 degrees C showed that at increasing the linoleic acid concentration a sharp transition from monomers to micelles occurs at 167 micrometer. At pH 9 and 8 formation of acid-soap dimers from monomers starts at 60 micrometer and 21 micrometer respectively. The concentration range at which only monomers exist is therefore markedly reduced. For 13-L-hydroperoxylinoleic acid at pH 10 acid-soap formation still takes place, starting at approx. 220 micrometer. The total lipid concentration at which acid-soap or micelle formation starts in mixtures of linoleic acid and 13-L-hydroperoxylinoleic acid has been determined in relation to the molar ratio of both acids.