Continuous ethyl oleate synthesis by lipases produced by solid-state fermentation by Rhizopus microsporus

• Published in: Bioresource technology Vol. 265; pp. 52 - 58
• Main Authors: Martínez-Ruiz, Antonio, Tovar-Castro, Luz, García, Hugo Sergio, Saucedo-Castañeda, Gerardo, Favela-Torres, Ernesto
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.10.2018
• Subjects: Fatty acid ethyl ester; Lipases; Rhizopus microspores; Solid-state fermentation; Fatty acid ethyl ester; Solid-state fermentation; Lipases; Rhizopus microspores
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.05.080

[Display omitted] •A naturally immobilised lipase was produced by solid-state fermentation.•The biocatalyst does not require extraction, purification and immobilisation steps.•Ninety percent conversion of ethyl oleate is achieved in 60 min of reaction.•The biocatalyst maintained its activity unchanged for 25 h of continuous operation. 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 300 rpm during 12 h of continuous reaction did not affect the biocatalytic conversion, allowing substrate conversions greater than 90% that were obtained with 50 mM oleic acid at a molar ratio of 1:2 during 14 h reaction. In contrast, substrate conversion was 70% with 100 mM oleic acid at a flow rate of 2 mL/min during 25 h of reaction. These results are promising and offer a technical alternative for the development of accessible biocatalysts that can be used in continuous operations.