Martinez-Ruiz_2018_Bioresour.Technol_265_52

Lipases produced by solid-state fermentation were used directly as biocatalysts for continuous synthesis of ethyl oleate in a continuously stirred tank reactor. The effect of biocatalyst reutilisation, molar ratio of substrates, agitation rate and feed rate on the esterification of oleic acid with ethanol were investigated. The catalyst maintained 90% conversion for four batch cycles with a 1:2 molar ratio (oleic acid:ethanol). Mechanical agitation at 200 and 300rpm during 12h of continuous reaction did not affect the biocatalytic conversion, allowing substrate conversions greater than 90% that were obtained with 50mM oleic acid at a molar ratio of 1:2 during 14h reaction. In contrast, substrate conversion was 70% with 100mM oleic acid at a flow rate of 2mL/min during 25h of reaction. These results are promising and offer a technical alternative for the development of accessible biocatalysts that can be used in continuous operations.