Production of Novel Tetrahydroxyfuranyl Fatty Acids from α-Linolenic Acid by Clavibacter sp. Strain ALA2

Abstract

Previously, it was reported that a newly isolated microbial culture, Clavibacter sp. strain ALA2, produced trihydroxy unsaturated fatty acids, diepxoy bicyclic fatty acids, and tetrahydroxyfuranyl fatty acids ( ). In this study, we found that Clavibacter sp. strain ALA2 produced novel THFAs, including 13,16-dihydroxy-12-THFA, 15-epoxy-9(Z)-octadecenoic acid (13,16-dihydroxy-THFA), and 7,13,16-trihydroxy-12, 15-epoxy-9(Z)-octadecenoic acid (7,13,16-trihydroxy-THFA), from ␣-linolenic acid (9,12,15-octadecatrienoic acid). The chemical structures of these products were determined by gas chromatography-mass spectrometry and proton and 13 C nuclear magnetic resonance analyses. The optimum incubation temperature was 30°C for production of both hydroxyTHFAs. 13,16-Dihydroxy-THFA was detected after 2 days of incubation, and the concentration reached 45 mg/50 ml after 7 days of incubation; 7,13,16-trihydroxy-THFA was not detected after 2 days of incubation, but the concentration reached 9 mg/50 ml after 7 days of incubation. The total yield of both 13,16-dihydroxy-THFA and 7,13,16-trihydroxy-THFA was 67% (wt/wt) after 7 days of incubation at 30°C and 200 rpm. In previous studies, it was reported that Clavibacter sp. strain ALA2 oxidized the C-7, C-12, C-13, C-16, and C-17 positions of linoleic acid (n-6) into hydroxy groups. In this case, the bond between the C-16 and C-17 carbon atoms is saturated. In ␣-linolenic acid (n-3), however, the bond between the C-16 and C-17 carbon atoms is unsaturated. It seems that enzymes of strain ALA2 oxidized the C-12-C-13 and C-16-C-17 double bonds into dihydroxy groups first and then converted them to hydroxy-THFAs.

Bioconversion of n−3 and n−6 PUFA by Clavibacter sp. ALA2

“…2). We reported earlier that strain ALA2 converted α-linolenic acid to 13,16-dihydroxy-12,15-epoxy-9(Z)-octadecenoic acid and 7,13,16-trihydroxy-12,15-epoxy-9(Z)-octadecenoic acid (15). From product structures obtained from these n-3 PUFA, it seems that strain ALA2 places hydroxyl groups at the same positions from the omega (ω)-terminal and cyclizes them to THF ring despite their varying degrees in carbon chain numbers and double bonds.…”

Identification of molecular species of polyol oils produced from soybean oil by Pseudomonas aeruginosa E03-12 NRRL B-59991

“…Our previous research established that microbial systems can convert FA to ricinoleic acid-type oxygenated FA, including many bioactive FA such as monohydroxy-, dihydroxy-and trihydroxy-unsaturated FA, tetrahydrofuranyl unsaturated FA, and diepoxy bicyclic unsaturated FA (Hou, 1994(Hou, , 1995(Hou, , 1997Hou et al, 1998Hou et al, , 2001Gardner et al 2000;Iwasaki et al, 2002;Hosokawa et al, 2003aHosokawa et al, , 2003bHosokawa et al, , 2003cHou and Hosokawa, 2005;Chang et al, 2007;Su et al, 2011;Bae et al, 2010). However, the biobased polymer industry requires acylglycerol (soybean oil) polyols and not FA polyols.…”

Production of polyol oils from soybean oil by bioprocess: results of microbial screening and identification of positive cultures

“…Our previous research established that microbial systems can convert FA to ricinoleic acid-type oxygenated FA, including many bioactive FA such as monohydroxy-, dihydroxy-and trihydroxy-unsaturated FA, tetrahydrofuranyl unsaturated FA, and diepoxy bicyclic unsaturated FA (Hou et al, 1993(Hou et al, , 1998(Hou et al, , 2001Hou, 1994Hou, , 1995Hou, , 1997Gardner et al, 2000;Iwasaki et al, 2002;Hosokawa et al, 2003aHosokawa et al, , 2003bHosokawa et al, , 2003cHou and Hosokawa, 2005;Chang et al, 2007;Suh et al, 2011;Bae et al, 2010). The bio-based polymer industry, however, requires acylglycerol (soybean oil) polyols and not FA polyols.…”