Screening of lipases for enzymatic concentration of γ-linolenic acid (GLA) from seed oils

Abstract

An enzymatic method that involves seed oil hydrolysis and selective esterification of free fatty acids (FFAs) has been essayed for screening of Upases in order to concentrate γ-linolenic acid (GLA; 18:3n-6). This procedure has been essayed by using the seed oil of two plant species, Borago officinalis and Echium fastuosum. No GLA enrichment was observed in the FFA fractions resulting from the enzymatic hydrolysis performed by all essayed lipases. However, starting from the FFA fraction of B. officinalis seed oil, and after esterfication with Candida rugosa lipase, in the fatty acid (FA) unesterified fraction a 91% GLA purity was obtained after two successive esterifications, yielding 59% GLA. GLA from E. fastuosum seed oil was also esterified; GLA was concentrated in the FA unesterified fraction by using Mucor javanicus lipase, obtaining 64% purity and 68% GLA yield. © 2006, Blackwell Publishing.