Hydrolysis of menhaden oil by a Candida cylindracea lipase immobilized in a hollow-fiber reactor.
A lipase from Candida cylindracea immobilized by adsorption on microporous polypropylene fibers was used to selectively hydrolyze the saturated and monounsaturated fatty acid residues of menhaden oil at 40 degrees C and pH 7.0. At a space time of 3.5 h, the shell and tube reactor containing these hollow fibers gives a fractional release of each of the saturated and monounsaturated fatty acid residues (i.e., C14, C16, C16:1, C18:1) of ca. 88% of the corresponding possible asymptotic value. The corresponding coproduct glycerides retained over 90% of the initial residues of both eicosapentaenoic (EPA; C20:5) and docosahexaenoic (DHA; C22:6) acids. The half-life of the immobilized lipase was 170 h when the reactor was operated at the indicated (optimum) conditions. Rate expressions associated with a generic ping-pong bi-bi mechanism were used to fit the experimental data for the lipase catalyzed reaction. Both uni- and multiresponse nonlinear regression methods were employed to determine the kinetic parameters associated with these rate expressions. The best statistical fit of the uniresponse data was obtained for a rate expression, which is formally equivalent to a general Michaelis-Menten mechanism. After reparameterization, this rate expression reduced to a pseudo-first-order model. For the multiresponse analysis, a model that employed a normal distribution of the ratio of Vmax/Km with respect to the chain length of the fatty acid residues provided the best statistical fit of the experimental data.
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Department of Chemical Engineering, University of Wisconsin, 1415 Engineering Drive, Madison, Wisconsin 53706, USA.
Watkins
J
J
Hill
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CG
D019149:Bioreactors; D001709:Biotechnology / Q000379:methods; D002175:Candida / Q000201:enzymology*; D004281:Docosahexaenoic Acids / Q000378:metabolism*; D015118:Eicosapentaenoic Acid / Q000378:metabolism*; D004800:Enzymes, Immobilized / Q000378:metabolism*; D005395:Fish Oils / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D008049:Lipase / Q000378:metabolism*; D012044:Regression Analysis; D013997:Time Factors
D004800:Enzymes, Immobilized; D005395:Fish Oils; C033266:Menhaden oil; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid; D008049:Lipase