MICROBIAL HYDRATION OF CIS-9-ALKENOIC ACIDS

The activity of a cis-9-fatty acid hydratase produced by a Pseudomonas sp. (NRRL B-3266) isolated from soil was compared with that of another isolate previously reported (NRRL B-2994). The presence of appropriate fatty acids for at least 4 hr during aerobic growth in yeast extract medium increased subsequent enzyme activity. Such cells anaerobically hydrated several cis-9-alkenoic acids to 10-hydroxy fatty acids and aerobically formed 10-keto acids, which were partially degraded to shorter chain keto acids. Melting point, gas chromatography, infrared, mass spectrometry and optical rotatory dispersion data are given. Six fatty acids having cis-9-unsaturation produced hydrated products, but several enoic acids having trans-9-unsaturation or double bonds in other than the 9 position were inactive as substrates. The (-)-10-hydroxypalmitic acid produced from palmitoleic acid is considered to have the D configuration. Yields of 71% crude crystalline product from 15 g of oleic acid and 53% from 11 g of palmitoleic acid were obtained in 5-liter anaerobic fermentations with NRRL B-3266. Methyl esters, triolein and oleyl alcohol were not hydrated. © 1969 American Oil Chemists' Society.