ORIGINAL PAPER
C18 Unsaturated Fatty Acid Selectivity of Lipases During
the Acidolysis Reaction Between Tripalmitin and Oleic, Linoleic,
and Linolenic Acids
Ihsan Karabulut
•
Gokhan Durmaz
•
Ali Adnan Hayaloglu
Received: 11 November 2009 / Revised: 28 May 2010 / Accepted: 28 May 2010 / Published online: 13 June 2010
Ó AOCS 2010
Abstract The C18 unsaturated fatty acid (UFA) selec-
tivity of three immobilized lipases, namely, Lipozyme TL
IM from Thermomyces lanuginosa, Lipozyme RM IM from
Rhizomucor miehei, and Novozym 435 from Candida
antarctica, was determined in acidolysis conducted in
hexane. Tripalmitin with a mixture of equimolar quantities
of C18 UFAs was used as the substrate. Significantly dif-
ferent incorporation rates were observed for C18 UFAs
used (p \ 0.05). The highest incorporation was obtained
for all three C18 UFAs with Novozym 435 followed by
Lipozyme RM IM and Lipozyme TL IM catalyzed acid-
olysis under default conditions (substrate mole ratio 1:1;
temperature 50 °C; reaction time 6 h; enzyme dosage
10%). Incorporation of the equimolar quantities of C18
UFAs was in the order C18:3 [ C18:2 [ C18:1 which also
reflects C18 UFAs preferences of the lipases. The effects of
operating variables on incorporation or UFA selectivity of
lipases were also investigated. Among the experimental
parameters including the mole ratio of fatty acid to triolein,
temperature, enzyme dosage, and time on incorporation,
the effect of the substrate mole ratio on UFA selectivity
was greater than those of the others.
Keywords Lipase Á Selectivity Á Acidolysis Á
Unsaturated fatty acid Á Tripalmitin Á
Thermomyces lanuginosa Á Rhizomucor miehei Á
Candida antarctica
Introduction
Lipases [triacylglycerol (TAG) acylhydrolases, E.C. 3.1.1.3]
are very versatile enzymes that catalyze a large number of
reactions. Lipases can be used as biocatalyst for hydrolysis,
esterification, acidolysis, interesterification and modification
of fats and oils [1]. The acidolysis activity of the lipases
has been widely used for transesterification between
TAG and fatty acid (FA) to produce structured lipids
(SLs) [2].
Lipases have various degrees of selectivity towards FAs
involved in fat and oil modification. Lipase specificity may
be due to the structural features of the substrate, such as FA
chain length, unsaturation, stereochemistry, physicochem-
ical factors at the interface, and differences in the binding
site of the enzyme. The reactivity of FAs may vary
depending on the composition of substrates, water activity,
nature of solvents and source of lipase [3]. There are
numerous reports in the literature evaluating the selectivity
of commercially available lipases in hydrolysis, esterifi-
cation and transesterification reactions. The FA selectivity
of commercially available lipases evaluated in acidolysis
with substrate combinations of different acyl donors and
the same TAG [4] or the same FA (acyl donor) and dif-
ferent TAGs [5]. Hamam and Shahidi [6, 7] examined the
effect of chain length, number of double bonds, the loca-
tion and geometry of double bonds, the reaction conditions,
and the reactivity of five lipases on the incorporation of
long-chain fatty acids (LCFAs) into TAGs, such as tri-
stearin, trilinolein and trilinolenin. Shimada et al. [8]
determined FA specificity of Rhizopus delemar lipase in
acidolysis using randomly interesterified oil. FA selectivity
of lipase from Geotrichum candidum was determined
in esterification reaction using LCFAs and 1-butanol by
Sonnet et al. [9].
I. Karabulut (&) Á G. Durmaz Á A. A. Hayaloglu
Department of Food Engineering, Inonu University,
44280 Malatya, Turkey
e-mail: ikarabulut@inonu.edu.tr
123
J Am Oil Chem Soc (2010) 87:1301–1307
DOI 10.1007/s11746-010-1613-y