Conjugated Linoleic Acid Accumulation via 10-Hydroxy-12-Octadecaenoic Acid during Microaerobic Transformation of Linoleic Acid by Lactobacillus acidophilus

Abstract

Specific isomers of conjugated linoleic acid (CLA), a fatty acid with potentially beneficial physiological and anticarcinogenic effects, were efficiently produced from linoleic acid by washed cells of Lactobacillus acidophilus AKU 1137 under microaerobic conditions, and the metabolic pathway of CLA production from linoleic acid is explained for the first time. The CLA isomers produced were identified as cis-9, trans-11-or trans-9, cis-11-octadecadienoic acid and trans-9, trans-11-octadecadienoic acid. Preceding the production of CLA, hydroxy fatty acids identified as 10-hydroxy-cis-12-octadecaenoic acid and 10-hydroxy-trans-12-octadecaenoic acid had accumulated. The isolated 10-hydroxy-cis-12-octadecaenoic acid was transformed into CLA during incubation with washed cells of L. acidophilus, suggesting that this hydroxy fatty acid is one of the intermediates of CLA production from linoleic acid. The washed cells of L. acidophilus producing high levels of CLA were obtained by cultivation in a medium containing linoleic acid, indicating that the enzyme system for CLA production is induced by linoleic acid. After 4 days of reaction with these washed cells, more than 95% of the added linoleic acid (5 mg/ml) was transformed into CLA, and the CLA content in total fatty acids recovered exceeded 80% (wt/wt). Almost all of the CLA produced was in the cells or was associated with the cells as free fatty acid.

Linoleic Acid Isomerase inLactobacillus plantarumAKU1009a Proved to Be a Multi-Component Enzyme System Requiring Oxidoreduction Cofactors

“…It produced two CLA isomers, cis-9,trans-11-and trans-9,trans-11-CLA, from linoleic acid with 10-hydroxy-12-octadecenoic acids as intermediates. 18,19) These results suggest that the reaction involves hydration and dehydrating isomerization catalyzed by multiple enzymes, while all reported linoleic acid isomerases produced CLA directly from linoleic acid without any intermediates. Hence we hypothesize that there are new y To whom correspondence should be addressed.…”

Metabolic diversity in biohydrogenation of polyunsaturated fatty acids by lactic acid bacteria involving conjugated fatty acid production

“…Standard samples of CLA isomers,i.e., (CLA1) and trans-9,trans-11-18:2 (CLA2), and 10-hydroxy-12-18:1 (HY) were prepared as described previously (Ogawa et al 2001). All other chemicals used were of analytical grade and were commercially available.…”

“…GC-1700 gas chromatograph equipped with a flame ionization detector and a split injection system, and fitted with a capillary column (HR-SS-10, 50 m x 0.25 mm I.D., Shinwa Kako, Kyoto, Japan), as described previously (Ogawa et al 2001).…”

“…at the flow rate of 1.0 ml/min. Free fatty acids and pyrrolidide derivatives were prepared by saponification with sodium hydroxide and direct treatement with pyrrolidine-acetic acid, respectively, as described previously (Ogawa et al 2001 were subjected to mass spectroscopy (MS)-MS analysis and GC-MS analysis, respectively, as described previously (Ogawa et al 2001). …”

“…Secondary metabolism of fatty acids by marine algae also involves numerous polyunsaturated fatty acids (PUFAs) containing conjugated olefin systems, for example, cis-6,trans-8,trans-10,cis-12-octadecatetraenoic acid (18:4) produced from γ-linolenic acid (cis-6,cis-9,cis-12-18:3) by the coralline red alga Lithothamnion corallioides and bosseopentaenoic acid [cis-5,cis-8,trans-10,trans-12,cis-14-eicosapentaenoic acid (20:5)] produced from arachidonic acid [cis-5,cis-8,cis-11,cis-14-eicosatetraenoic acid (20:4)] by the marine red alga Bossiella orbigniana. On the other hand, except for the investigations on CLA production by 4 anaerobic bacteria including our previous works (Ogawa et al 2001;Kishino et al 2002a;Kishino et al 2002b;Ando et al 2003;Kishino et al 2003;Ando et al 2004), the microbial production of PUFA containing conjugated double bonds has not been extensively studied so far.…”