Article

Enzymatic Synthesis of Ascorbyl Palmitate in Organic Solvents: Process Optimization and Kinetic Evaluation

Food and Bioprocess Technology (Impact Factor: 3.13). 04/2012; 5(3):1068-1076. DOI: 10.1007/s11947-010-0398-1

ABSTRACT This work is focused on the optimization of reaction parameters for the synthesis of ascorbyl palmitate catalyzed by Candida antarctica lipase in different organic solvents. The sequential strategy of experimental designs proved to be useful in maximizing the
conditions for product conversion in tert-butanol system using Novozym 435 as catalyst. The optimum production were achieved
at ascorbic acid to palmitic acid mole ratio of 1:9, stirring rate of 150rpm, 70°C, enzyme concentration of 5wt.% at 17h
of reaction, resulting in an ascorbyl palmitate conversion of about 67%. Reaction kinetics for ascorbyl palmitate production
showed that very satisfactory reaction conversions (∼56%) could be achieved in short reaction times (6h). The kinetic empirical
model proposed showed ability to satisfactory represents and predict the experimental data.

KeywordsBiocatalysis–Neural network–Kinetics–Lipase–Ascorbyl palmitate–Experimental design

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Available from: Lindomar Lerin, Oct 30, 2014
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    • "In this initial step, some specific conditions were tested as following: use of solvent (10 mL of tert-butanol) without agitation; use of solvent with mechanical stirring (250 rpm); solvent-free system without agitation and solvent-free system with mechanical stirring (250 rpm). All experiments were then carried out under sonochemical irradiation of 132 W, temperature of 70° C, substrates molar ratio of 1:9, enzyme concentration of 5 wt% [20]. For the evaluated system that presented higher ascorbyl palmitate yields, a kinetic experiment, at the same experimental conditions cited before, was carried out to determine the reaction time to be fixed in the experimental design step. "
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