Microbial hydration ofCis‐9‐alkenoic acids

Abstract

The activity of acis‐9‐fatty acid hydratase produced by aPseudomonas 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 severalcis‐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 havingcis‐9‐unsaturation produced hydrated products, but several enoic acids havingtrans‐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.

Hydration of linoleic acid by bacteria isolated from ruminants

“…Pseudomonas strain NRRL-B-3266 [3], Acetobacterium woodii [4], Nocardia cholesterolicum [5], a Flavobacterium sp. [6], Lactobacillus plantarum [8] and an extract from Pseudomonas strain NRRL-B-2994 [7] have been shown to convert linoleic acid to 10-hydroxy-12-octadecenoic acid.…”

Conversion of Long-Chain Unsaturated Fatty Acids to Hydroxy Acids by Human Intestinal Bacteria

“…The Pseudomonas studied by Davis et al (1969) was also able to perform this reaction, but it has not previously been reported in intestinal bacteria. Unlike the Pseudomonas, however, none of the intestinal bacteria tested was able to hydrate linoleic acid, to form an unsaturated hydroxyacid similar to ricinoleic acid.…”

“…This indicates strongly that the product was an hydroxypalmitic acid with the hydroxyl group on one of the carbon atoms from 5 to 13 (Tulloch, 1964). Although the position of the hydroxyl group was not determined, in the only other report of an hydroxypalmitic acid formed from palmitoleic acid by a micro-organism this was stated to be 10-hydroxypalmitic (Davis et al, 1969). It is therefore assumed that the product formed by intestinal bacteria is probably 10-hydroxypalmitic.…”

A novel keto fatty acid from cassia occidentalis seed oil

“…The oil did not respond to Halphen [6] and picric acid TLC [7] tests indicating the absence of cyclopropenoid and epoxy fatty acids, respectively. However, the oil responded to the DNPH test [8] showing the presence of a keto group. Methyl esters were prepared by refluxing the oil in methanol in acidic medium [9].…”