Food Lipids: Chemistry, Nutrition, and Biotechnology

Fatty acid esters of polyols are useful as surfactants. Polyglycerol–fatty acid
esters have been prepared in good yields by transesterification of polyglycerol, adsorbed
on silica gel, with methyl esters of fatty acids (215).
Propylene glycol monoesters, suitable as emulsifiers, have been prepared in
good yields by reacting a fatty acid anhydride with 1,2-propanediol in the presence
of lipase from a Pseudomonas sp. (216). Esterification of eicosapentaenoic and docosahexaenoic
acids with 1,2-propanediol in the presence of lipase from Rhizomucor
miehei provides propylene glycol monoester emulsifiers that are potentially beneficial
to health (217).
Polyethylene glycol esters of fatty acids, widely used as nonionic surfactants,
have been prepared in essentially quantitative yields by esterification of oleic acid
with polyethyleneglycol, catalyzed by lipase from Rhizomucor miehei (218).
Medium and long chain alcohols (C 8–C 16) have been efficiently esterified with
lactic acid and glycolic acid using lipase B from Candida antarctica (Novozym 435)
as biocatalyst (219). Using the same lipase ethyl lactate has been transesterified with
n-octyl-�-D-glucopyranoside to obtain n-octyl-�-D-glucopyranosyl lactate in high
yield (220).
Ascorbyl palmitate, used as antioxidant in foods and cosmetics, has been prepared
in good yields by esterification of ascorbic acid with palmitic acid using lipase
from Bacillus stearothermophilus SB 1 (221) and Candida antarctica (Novozym
435) (222). Esterification of cinnamic acid with 1-octanol using Novozym 435 also
provides the octyl ester in moderate yields (222). Similarly, using lipase B from
Candida antarctica (Chirazyme L2) 6-O-palmitoyl-L-ascorbic acid and 6-O-eicosapentaenoyl-L-ascorbic
acid have been prepared, respectively, via transesterification
with vinyl palmitate (223) and condensation with eicosapentaenoic acid (224). Transesterification
of L-methyl lactate with ascorbic acid or retinol using Novozym 435
gives high yields of ascorbyl-L-lactate and retinyl-L-lactate, respectively (225).
7. Amides
Reaction of a triacylglycerol mixture, such as soybean oil, with lysine, catalyzed by
lipase from Rhizomucor miehei yields acyl amides, i.e., N-�-acyllysines (226). Reaction
of ethyl octanoate with ammonia (ammonolysis), catalyzed by lipase from
Candida antarctica, provides octanamide in near-quantitative yields (227). One pot
enzymatic synthesis of octanamide in high yield via esterification of octanoic acid
with ethanol, followed by ammonolysis of the resulting ethyl octanoate, both reactions
being conducted using the lipase from Candida antarctica has also been reported
(227). Lipase-catalyzed direct amidation of carboxylic acids by ammonia and
ammonium salts has been reported (228) and various applications of lipase-catalyzed
aminolysis and ammonolysis have been recently reviewed (229).
8. Fatty Acids
Lipase-catalyzed hydrolysis can be applied for the production of fatty acids from
fats using, e.g., a nonspecific lipase preparation from Candida rugosa (syn. Candida
cylindracea) (230–238), Pseudomonas sp. (239–243), Aspergillus sp. (244), Thermomyces
lanuginosus (245), and Chromobacterium viscosum (246) as alternative
mild processes compared to drastic ‘‘steam splitting’’ (Fig. 28). Specifically, fatty
acids have been obtained by lipase-catalyzed hydrolysis of technically important fats,
such as animal fats (236), castor oil (243), palm stearin (242), and the thermally
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