3.6.2 Cutinase
Cabral and co-workers have investigated the use of a recombinant cutinase from
Fusarium solanito hydrolyze triglycerides and to form esters in w/o-MEs. Their
work has demonstrated that AOT systems, although successful in hosting reac-
tions, rapidly inactivated cutinase (Sebastiao et al., 1993; Melo et al., 1998). Im-
proved stability (although not activity) have been observed for CTAB and lecithin
surfactant systems (Pinto-Sousa et al., 1996; Melo et al., 1998).
3.6.3 Lipoxygenases
The formation of hydroperoxides from unsaturated fatty acids (e.g., linoleic acid,
18:29cis,12cis) and dissolved oxygen catalyzed by soybean lipoxygenase has been con-
ducted in AOTw/o-MEs by several groups (Luisi et al., 1984; Kurganov et al., 1989;
Hochkoeppler and Palmieri, 1990; Shkarina et al., 1992; Rodakiewicz-Nowak et al.,
1996). On the positive side, the reaction occured readily in this system, providing an
optically clear medium well-suited forin situmonitoring of the reaction. However,
the reaction rates observed were quite slow, presumably due to unfavorable parti-
tioning of substrate and irreversible inactivation of the enzyme (Rodakiewicz-Now-
ak et al., 1996). A nonionic surfactant system did not fare any better (Piazza, 1992).
3.7 Conclusions
Water-in-oil microemulsions provide a simple reaction system to employ for eval-
uating the modification of lipids via enzymology in screening experiments. A major
advantage of w/o-MEs solutions is the ability to analyze reactions in situ due to their
optical transparency. Although currently not employed on a large scale, the devel-
opment of microemulsion gels appears to be an important process-scale application
resulting from w/o-ME/enzyme technology.
3.8 References
Aires-Barros, M.R., Cabral, J.M.S. (1991), Selective separation and purification of two lipase fromChro-
mobacterium viscosumusing AOT reversed micelles.Biotechnol. Bioeng.38,1302–1307.
Avramiotis, S., Stamatis, H., Kolisis, F.N., Lianos, P., Xenakis, A. (1996), Structural studies of lecithin-
and AOT-based water-in-oil microemulsions, in the presence of lipase.Langmuir12,6320–6325.
Ayyagari, M.S., John, V.T. (1995), Substrate-induced stability of the lipases fromCandida cylindraceain
reversed micelles.Biotechnol. Lett.17,177–182.
Backlund, S., Eriksson, F., Hedstro ̈m, G., Laine, A., and Rantala, M. (1996), Lipase-catalyzed enantio-
selective esterifications using different microemulsion-based gels.Coll. Poly. Sci274,540–547.
Backlund, S., Eriksson, F., Kanerva, L.T., Rantala, M. (1995), Selective enzymatic reactions using micro-
emulsion-based gels.Coll. Surf. B.: Biointerf.4,121–127.