Strategies for enriching erucic acid from Crambe abyssinica oil by improved Candida antarctica lipase A variants

Abstract

Abstract Erucic acid (C22:1, Δ13Z) is an interesting building block for the oleochemical industry and is abundantly present in Crambe abyssinica seed oil (∼59% of C22:1). For the enrichment of fatty acids (FA), lipases can be employed and we have found in a previous protein engineering study suitable variants of lipase A from Moesziomyces antarcticus (CAL-A) for the enrichment of C22:1 from Crambe oil derived ethyl esters (FAEE). To continue with this task a thorough investigation of the best four variants behaviour when using the natural Crambe oil (TAG) as substrate was performed. CAL-A variants showed to be able to enrich C22:1 up to 80% using both substrates, FAEE and TAG. In particular, CAL-A wild type and the double mutant V238 L/V290 L (V1) proved to be the most suitable biocatalysts, because they displayed the best theoretical recovery yields for C22:1 enriched fractions (60–74%). Further characterization of these lipases concerning their temperature profile showed an optimum at high temperatures (60–75 °C) preserving their selectivity in reactions up to 50 °C. Finally, upscaling of the Crambe oil hydrolysis (from 0.01 g to 1 g) with V1 resulted in an enriched esterified C22:1 fraction of 74%.