2 Fractionation of Fatty Acids and Other Lipids
Using Lipases
Kumar D. Mukherjee
2.1 Introduction
Lipases (triacylglycerol acylhydrolases, EC 3.1.1.3) from various organisms have
been used successfully as biocatalysts in bioorganic synthesis (Chen and Sih,
1989; Klibanov 1990; Haraldsson, 1992; Ko ̈tting and Eibl, 1994; Jaeger and
Reetz, 1998; Kazlauskas and Bornscheuer, 1998) and modification of fats and other
lipids via hydrolysis, esterification and interesterification (Macrae, 1983; Mukher-
jee, 1990; Gandhi, 1997). Since most of the commercially available lipase prepara-
tions are rather expensive, lipase-catalyzed reactions are industrially attractive
mainly for the manufacture of products of good commercial value (Vulfson,
1994). Processes for the preparation of purified fatty acids and lipids from inexpen-
sive starting materials using lipase-catalyzed reactions should be commercially at-
tractive.
This chapter covers the specificity of lipases in view of their application in the
fractionation of fatty acids and their derivatives via kinetic resolution.
2.2 Fractionation of fatty acids and other lipids
by lipase-catalyzed reactions
The ability of certain lipases to discriminate against or prefer particular fatty acids or
acyl moieties of lipids has been utilized for the enrichment of such fatty acids or their
esters from natural fats and oils via selective hydrolysis, esterification and interes-
terification, i.e. via kinetic resolution (Figure 1) (Mukherjee, 1995; 1996). Moreover,
the regioselectivity of certain triacylglycerol lipases for the cleavage of fatty acids
esterified at, for examplesn-1,3-positions of triacylglycerols, has been utilized to
enrich those fatty acids via kinetic resolution through regioselective hydrolysis, es-
terification or transesterification.
2.2.1 Lipase specificities
Fatty acid selectivity and positional specificity of triacylglycerol lipases are well
documented in the literature (Mukherjee, 1990; 1998; Kazlauskas and
Bornscheuer, 1998). Fatty acid selectivity and activity of several commercially im-
portant lipase preparations have been evaluated (Rangheard et al., 1989; Mukherjee
Enzymesin LipidModification.Editedby UweT. Bornscheuer
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