Selectivity of lipases: isolation of fatty acids from castor, coriander, and meadowfoam oils

The lipase-catalyzed hydrolysis of castor, coriander, and meadowfoam oils w as studied in a two-phase water/oil system. The lipases from Candida rugosa and Pseudomonas cepacia released all fatty acids from the triglycerides ra ndomly, with the exception of castor oil. In the latter case, the P. cepaci a lipase discriminated against ricinoleic acid. The lipase from Geotrichum candidum discriminated against unsaturated acids having the double bond loc ated at the Delta -6 (petroselinic acid in coriander oil) and Delta -5 (mea dowfoam oil) position or with a hydroxy substituent (ricinoleic acid). The expression of the selectivities of the G. candidum lipase was most pronounc ed in lipase-catalyzed esterification reactions, which was exploited as par t of a two-step process to prepare highly concentrated fractions of the aci ds. In the first step the oils were hydrolyzed to their respective free fat ty acids, in the second step a selective lipase was used to catalyze esteri fication of the acids with l-butanol. This resulted in an enrichment of the targeted acids to approximately 95-98% in the unesterified acid fractions compared to the 70-90% content in the starting acid fractions.