Fatty acid selectivity: The selectivity of lipases ofGeotrichum candidum

Abstract

The relative reactivities of several long‐chain fatty acids in esterifications with 1‐butanol catalyzed by lipases ofGeotrichum candidum were evaluated. As has been noted previously, these lipases are not uniformly highly selective forcis‐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 γ‐linolenic and ricinoleic acid were also low compared to that of oleic. An examination of the effect of the alcohol upon the relative reactivities of acids showed that one could enhance fatty acid selectivity by proper choices of alcohol. For example, oleic acid esterifies 2.5 times faster than palmitic acid with 1‐butanol catalyzed by Amano GC‐4 lipase, but esterifies over 50 times faster with 2‐methyl‐1‐propanol or cyclopentanol.

Fatty acid preference of mycelium-bound lipase from a locally isolated strain of Geotrichum candidum

“…From left: S1 = 1-mono-stearoyl-racglycerol, S2 = 1,2-diolein, S3 = 1,3-diolein, S4 = oleic acid and S5 = triolein (Table 3) of the fatty acid. These results agree with those published by other researchers such as Sonnet et al (1993) and Shimada et al (1995) that G. candidum lipase strongly discriminates against FA with chain lengths longer than 18 carbon atoms. Results in Table 1 further proved that the lipase from G. candidum even in crude form (myceliumbound without purification) displayed high-substrate selectivity for unsaturated fatty acids that contain a cis-9 double bond, as has been reported for crude free lipases from NRRL Y-553 (Baillargeon and McCarthy 1991).…”

Enzymes as biocatalysts in the modification of natural lipids

“…Complete speci®city should lead to no oleic acid in the liberated acids though this value must increase if hydrolysis proceeds beyond 67%. Signi®cant selectivity of other kinds has also been reported for Geotrichum candidum 10,11 and for Penicillium sp. 12 Many enzymes Table 2.…”

Enzymatic Isolation and Enrichment of Erucic Acid From Hea Seed Oils: Current Status

“…In addition to the common capability for lipases to cleave ester bonds, some lipases hold special specificities, which are essentially important for EA isolation and enrichment (Piazza et al, 1992;Sonnet et al, 1993a;Stadler et al, 1995;Lee and Parkin, 2000).…”