AZTI-Tecnalia obtains isomers of conjugated linoleic acid from micro-organisms

Conjugated linoleic acid is a mixture of isomers, some of which have functional properties and, thereby, are considered to be molecules of high added value. Amongst the possible isomers, the 9-cis, 11-trans 18:2 and 10-trans, 12-cis 18:2 configurations have a positive effect on the reduction of body fat and this is why they are of such interest. These fatty acids are currently produced by chemical synthesis and their addition to what are called functional foodstuffs is common due to their health-giving properties.

The aim of the research undertaken by AZTI-Tecnalia was to study the efficiency of certain lactic acid bacteria on the production of potentially functional fatty acids by means of the isomerisation of linoleic acid into its conjugated isomers. Results indicate that, amongst the lactic acid bacteria analysed, at least one of them can conjugate the double bonds of the linoleic acid, thus producing two isomers: 9-cis, 11-trans 18:2 and 9-trans, 11-trans 18:2. The transformation of the linoleic acid into its conjugates is selective when micro-organisms are employed, thus producing just two of the isomers from all those possible. The production yields obtained were low and, because of this, further research is being carried out to improve them.

In conclusion, the stereospecific production of certain conjugated isomers of linoleic acid with functional properties is possible, by using micro-organisms accepted as safe in the preparation of foodstuffs. Thus, it is to be hoped that, by means of using these micro-organisms, functional foodstuffs can be prepared without recourse to chemical synthesis.