Submitted to: Journal of the American Oil Chemists' Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2003
Publication Date: 11/1/2003
Citation: Hosokawa, M., Hou, C.T., Weisleder, D. 2003. Bioconversion of n-3 and n-6 PUFA by Clavibacter sp. ALA2. Journal of the American Oil Chemists' Society. 80(11):1085-1091. Interpretive Summary: Hydroxy fatty acids are used for synthesis of specialty chemicals, special military nylon, plastisizers, coatings and physiologically active agents. Recently, we found that Clavibacter strain ALA2 (a bacterium) converted 20-carbon and 22-carbon essential fatty acids into new hydroxy and epoxy fatty acids. Both fatty acids have their first double bond located at the third carbon (omega-3) position. Strain ALA2 also converted two other essential fatty acids having their first double bond at the sixth carbon (omega-6) position into products different in structures to those obtained from omega-3 fatty acids. New products synthesized from these fatty acids include five-member ring and six-member ring cyclic fatty acids. Thus, the structures of bioconversion products were different between omega-3 and omega-6 unsaturated fatty acids. Furanyl fatty acids (five-member ring) are known anticancer drugs. The new products have great potential to be used as bioactive agents and raw materials for synthesis of specialty chemicals. Application of these products either for bioactive agents or raw material for synthesis of specialty chemicals will benefit U.S. farmers.
Technical Abstract: Clavibacter sp. ALA2 oxidized w-3 and w-6 polyunsaturated fatty acids (PUFAs) into a variety of oxylipins. Structures of products converted from eicosapentaenoic acid and docosahexaenoic acid were determined as 15, 18-dihydroxy-14,17-epoxy-5(Z),8(Z),11(Z)- eicosatrienoic acid and 17,20-dihydroxy-16,19-epoxy-4(Z),7(Z),10(Z),13(Z)-docosatetraenoic acid by GC-MS and NMR analyses. In contrast, y-linolenic acid and arachidonic acid were converted to diepoxy bicyclic fatty acids, tetrahydrofuranyl monohydroxy fatty acids, and trihydroxy fatty acids. Thus, the structures of bioconversion products were different between w-3 and w-6 PUFAs. Furthermore, strain ALA2 places hydroxy groups and cyclic structures at the same position from the w-terminal despite the number of carbons in the chain and the double bonds in the PUFAs.