Microbial conversion of linoleic and linolenic acids to unsaturated hydroxy fatty acids

Abstract

The conversion of oleic acid to 10‐hydroxystearic acid with resting cells of Nocardia cholesterolicum (NRRL 5767) has been previously reported. These same microorganisms also convert linoleic and linolenic acids to 10‐hydroxy‐12 c ‐octadecenoic and 10‐hydroxy‐12 c ,15 c ‐octadecadienoic acids, respectively. The reaction occurs best at 35°C and a pH of 6.5. Under optimum conditions, 75–80% of the unsaturated fatty acid substrate is converted to the corresponding hydroxy acid. The hydroxy products were characterized by gas chromatography, gas chromatographymass spectrometry, nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy. Other microorganisms that successfully converted these substrates include another strain of Nocardia cholesterolicum (NRRL 5768) and Nocardia sp. (NRRL 5636).