FATTY-ACID SELECTIVITY - THE SELECTIVITY OF LIPASES OF GEOTRICHUM-CANDIDUM

The relative reactivities of several long chain fatty acids in esterif ications with 1-butanol catalyzed by lipases of Geotrichum candidum we re evaluated. As has been noted previously, these lipases are not unif ormly highly selective for cis-9 unsaturated fatty acids. However, the lipase preparations examined do uniformly discriminate against fatty acids having a chainlength greater than C-18 such as erucic acid. The reactivities of gamma-linolenic and ricinoleic acid were also low comp ared to that of oleic. An examination of the effect of the alcohol upo n the relative reactivities of acids showed that one could enhance fat ty acid selectivity by proper choices of alcohol. For example, oleic a cid esterifies 2.5 times faster than palmitic acid with 1-butanol cata lyzed by Amano GC-4 lipase, but esterifies over 50 times faster with 2 -methyl-1-propanol or cyclopentanol.