ofc-linolenoyl moieties in the unhydrolyzed acylglycerols, i.e., tri-, di- and mono-
acylglycerols, whereas the other acyl moieties are cleaved to fatty acids (Figure 4;
Table 2).
Fatty acid concentrates containing about 75 %c-linolenic acid have been prepared
via selective esterification of fatty acids of evening primrose oil and borage oil with
n-butanol, catalyzed by lipase fromR. miehei(Syed Rahmatullah et al., 1994a).
Partial hydrolysis of evening primrose oil using lipase fromC. rugosaleads to
enrichment ofc-linolenic acid from about 10 % in the starting material to about
47 % in the unhydrolyzed acylglycerols (Syed Rahmatullah et al., 1994b). Simi-
larly, hydrolysis of borage oil using lipase fromC. cylindracearesults in enrichment
ofc-linolenic acid from about 20 % in the starting material to about 48 % in the
unhydrolyzed acylglycerols (Syed Rahmatullah et al., 1994b).
The selectivity of the lipases fromR. mieheiandC. rugosatowardsc-linolenic
acid has been utilized to concentrate this fatty acid from fatty acids of fungal oil via
2.2 Fractionation of fatty acids and other lipids by lipase-catalyzed reactions 31
Figure 3. Scheme of kinetic resolution for the enrichment ofc-linolenic (GLA), n-3 docosahexaenoic
(DHA) or petroselinic (PET) acid via lipase-catalyzed selective esterification of fatty acid mixtures with
n-butanol.
Figure 4. Scheme of kinetic resolution for the enrichment ofc-linolenic (GLA), n-3 docosahexaenoic
(DHA), erucic (ERUC) or petroselinic (PET) acid via lipase-catalyzed selective hydrolysis of triacylgly-
cerols.