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Food Lipids: Chemistry, Nutrition, and Biotechnology

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Lipase-catalyzed selective hydrolysis of triacylglycerols from meadowfoam oil<br />

or selective esterification of meadowfoam fatty acids have been reported for the<br />

enrichment of cis-5-eicosenoic acid in the acylglycerols <strong>and</strong> unesterified fatty acids,<br />

respectively (283).<br />

Fennel (Foeniculum vulgare) oil has been selectively hydrolyzed using a lipase<br />

from Rhizopus arrhizus for the enrichment of petroselinic acid in the unhydrolyzed<br />

acylglycerols (284). The acylglycerols were separated from the fatty acids using an<br />

ion exchange resin <strong>and</strong> subsequently hydrolyzed by the lipase from C<strong>and</strong>ida rugosa<br />

to yield a fatty acid concentrate containing 96% of petroselinic acid.<br />

Highly purified concentrate of petroselinic acid has also been prepared from<br />

fatty acids of cori<strong>and</strong>er oil via selective esterification with n-butanol, catalyzed by<br />

lipase from germinating rapeseed (Fig. 37) (276).<br />

Fatty acid concentrates containing 85% hydroxy acids, such as lesquerolic (14hydroxy-cis-11-eicosenoic)<br />

<strong>and</strong> auricolic (14-hydroxy-cis-11-cis-17-eicosadienoic)<br />

acids, have been prepared from lesquerella oil by their selective cleavage catalyzed<br />

by lipase from Rhizopus arrhizus (285).<br />

Fatty acids of Biota orientalis seed oil have been selectively esterified with nbutanol<br />

using lipase from C<strong>and</strong>ida rugosa to enrich cis-5-polyunsaturated fatty acids,<br />

e.g., all-cis-5,11,14-octadecatrienoic <strong>and</strong> all-cis-5,11,14,17-octadecatetraenoic acid;<br />

the level of total cis-5-polyunsaturated fatty acids is raised from about 15% in the<br />

starting material to about 73% in the unesterified fatty acids (286). Selective hydrolysis<br />

of the seed oil of Biota orientalis by the lipase from C<strong>and</strong>ida rugosa leads to<br />

enrichment of the cis-5-polyunsaturated fatty acids in the acylglycerols to about 41%<br />

(286). Apparently, fatty acids/acyl moieties having a cis-5 double bond are also<br />

discriminated against by some lipases.<br />

A recent comprehensive review (248) covers the applications of lipase-catalyzed<br />

reactions for the enrichment of fatty acids via kinetic resolution.<br />

9. Phospholipids<br />

Interestingly, not only phospholipases A1 <strong>and</strong> A2, as described in Sec. B, but also<br />

some triacylglycerol lipases cleave the fatty acids from the sn-1 <strong>and</strong>/or sn-2 positions<br />

of diacylglycerophospholipids <strong>and</strong> also catalyze ester exchange reactions to modify<br />

the composition of the acyl moieties at the sn-1 <strong>and</strong>/or sn-2 positions of glycerophospholipids.<br />

Interestingly, triacylglycerol lipases, such as those from Rhizopus arrhizus<br />

<strong>and</strong> Rhizomucor miehei, have recently been found to be also able to catalyze<br />

the acyl exchange of galactolipids, e.g., via acidolysis of heptadecanoic acid with<br />

digalactosyldiacylglycerols (DGDG) (287). Modification of phospholipids using triacylglycerol<br />

lipases will be covered in Sec. B.1.<br />

Figure 37 Preparation of concentrates of petroselinic acid via lipase-catalyzed selective<br />

esterification of fatty acids from cori<strong>and</strong>er oil with n-butanol.<br />

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

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