ARS | Publication request: BIOCONVERSION OF N-3 AND N-6 POLYUNSATURATED FATTY ACIDS (PUFAS) BY STRAIN CLAVIBACTER SP.ALA2

Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: May 9, 2003
Publication Date: N/A

Technical Abstract: Microbial enzyme systems transform unsaturated fatty acids to functional substances. Previously, we reported that Clavibacter sp. ALA2 converted linoleic acid to unique cyclic fatty acids such as diepoxy bicyclic fatty acids (DEOA) and tetrahydrofuranyl fatty acids (THFA) as well as trihydroxy fatty acids (THOA). Now, we have investigated bioconversion of n-3 and n-6 polyunsaturated fatty acids (PUFAs) by strain ALA2 system. Bioconversions were carried out by adding a free fatty acid to a one-day-old culture (50 ml) and shaking at 200 rpm at 30°C for 2-7 days. Reaction products were detected and analyzed by GC, GC-MS and NMR. We found that strain ALA2 produced novel tetrahydrofuranyl fatty acids, 13,16-dihydroxy-12,15-epoxy-9(Z)- octadecenoic acid and 7,13,16-trihydroxy-12,15-epoxy-9(Z)- octadecenoic acid from alpha-linolenic acid (18:3, n-3). Strain ALA2 also converted eicosapentaenoic acid (20:5, n-3) and docosahexaenoic acid (22:6, n-3) to 15,18- dihydroxy-14,17-epoxy-icosatrienoic acid and 17,20-dihydroxy-16,19-epoxy-4(Z), 7(Z),10(Z),13(Z)-docosatetraenoic acid. In contrast, gamma-linolenic acid (18:3, n-6) and arachidonic acid (20:4, n-6) were converted to DEOA, THFA and THOA similar to linoleic acid reported previously. Therefore, strain ALA2 biotransformed n-3 and n-6 PUFAs into different cyclic fatty acids with hydroxyl groups. Strain ALA2 converted n-3 PUFAs to THFAs and n-6 PUFAs to DEOA, THFA and THOA.