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Food Lipids: Chemistry, Nutrition, and Biotechnology

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Figure 31 Preparation of concentrates of �-linolenic acid (GLA) via lipase-catalyzed selective<br />

hydrolysis of borage oil or evening primrose oil.<br />

Very recently, lipase-catalyzed selective hydrolysis of a microbial oil from Mortierella<br />

alpina has been employed to enrich arachidonic acid in the acylglycerols<br />

(270).<br />

The ability of lipase preparations from plants <strong>and</strong> microorganisms to discriminate<br />

against fatty acids/acyl moieties having cis-4-, cis-6, or cis-8 double bonds<br />

(Table 9) has been utilized for the enrichment of �-linolenic acid from fatty acid<br />

mixtures, derived from plant <strong>and</strong> microbial oils, by selective esterification of the<br />

fatty acids, other than �-linolenic acid, with n-butanol as outlined in Fig. 33 (271–<br />

276). Similarly, lipase-catalyzed esterification has been applied to enrich docosahexaenoic<br />

acid from fatty acid mixtures, derived from marine oils (272,276). Such<br />

concentrates might find nutraceutical applications in capsules.<br />

Typical data on enrichment of GLA via lipase-catalyzed selective esterification<br />

of fatty acids from borage oil with n-butanol are given in Fig. 34.<br />

Conjugated linoleic acids (CLA), predominantly a mixture of cis-9,trans-11octadecadienoic<br />

<strong>and</strong> trans-10,cis-12-octadecadienoic acids, have gained some interest<br />

as beneficial supplements for foods <strong>and</strong> feeds due to their potentially anticarcinogenic<br />

<strong>and</strong> immunological properties. However, it is not known which of the two<br />

major isomers is physiologically more active. With this background, a mixture con-<br />

Figure 32 Enrichment of �-linolenic acid (GLA) from borage oil by selective hydrolysis<br />

catalyzed by triacylglycerol lipase from C<strong>and</strong>ida cylindracea (syn. C. rugosa) according to<br />

Ref. 269: reaction temperature, 20�C; reaction time, 2 hours; degree of hydrolysis, 89%.<br />

Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.

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