12, 13-Epoxy-octadecenoate

In this paper, we investigated the bioconversion of n-3 and n-6 PUFA by strain ALA2. 13,16-Dihydroxy-12,15-epoxy-octadecenoic acid (13,16-dihydroxy-THFA) and... 

Graveland has shown that in the enzymic oxidation of linoleic acid in doughs and in flour-water suspensions the products include two isomeric hydroperoxy-acids, two isomeric hydroxy-acids, two isomeric hydroxy-epoxy-octadecenoic acids, and some trihydroxy-octadecenoic acids. 

Figure 11.1 Py/methylation GC/MS chromatograms of lead white pigmented linseed oil paint after 610 °C Curie point pyrolysis assisted with on line methylation using 2.5% methanolic TMAH (the sample and TMAH solution was applied onto a rotating Curie point wire pyrolysis time 6 s, interface 180°C). 1, heptenoic acid, methyl ester 2, heptanoic acid, methyl ester 3, butenedioic acid, dimethyl ester 4, butanedioic acid, dimethyl ester 5, octenoic acid, methyl ester 6, octanoic acid, methyl ester 7, pentenedioic acid, dimethyl ester 8, pentanedioic acid, dimethyl ester 9, nonanoic acid, methyl ester 10, hexanedioic acid, dimethyl ester 11, decanoic acid, methyl ester 12, heptanedioic acid, dimethyl ester 13, octanedioic acid, dimethyl ester 14, 1,2 benzenedicarboxylic acid, dimethyl ester 15, a methyl octanedioic acid, dimethyl ester 16, nonanedioic acid, dimethyl ester 17, a methoxy octanedioic acid, dimethyl ester 18, a methyl nonanedioic acid, dimethyl ester 19, a,a dimethyl nonenedioic acid, dimethyl ester 20a, a methyl nonenedioic acid, dimethyl ester 20b, a,a dimethyl nonanedioic acid, dimethyl ester 21, decanedioic acid, dimethyl ester 22, a methoxy nonanedioic acid, dimethyl ester 23, a methyl decan edioic acid, dimethyl ester 24, undecanedioic acid, dimethyl ester 25, a methoxy decan edioic acid, dimethyl ester 26, pentadecanoic acid, methyl ester 27, dodecanedioic acid, dimethyl ester 28, hexadecanoic acid, methyl ester 29, heptadecanoic acid, methyl ester 30, octadecanoic acid, methyl ester 31,8 methoxy 9 octadecenoic acid, methyl ester 32, 11 methoxy 9 octadecenoic acid, methyl ester 33, 9 methoxy 10 octadecenoic acid and 10 methoxy 8 octadecenoic acid 34, 9 oxo octadecanoic acid, 10 oxo octadecanoic acid 35, 9 epoxy octadecanoic acid 36, eicosanoic acid, methyl ester 37, 9,10 dimethoxy octadecanoic acid, methyl ester 38, docosanoic acid, methyl ester. Reprinted from J. Anal. Appl. Pyrol., 61, 1 2, van den Berg and Boon, 19, Copyright 2001, with permission from Elsevier...

See also Epoxy coatings Epoxy chalcone, 10 450 12,13-Epoxy-cis-9-octadecenoic (vernolic) acid, physical properties, 5 35t Epoxy coatings, 10 436 450 17 845. See also Epoxy can coatings for corrosion protection, 7 199 markets for, 10 442-449 performance of, 10 423 waterborne, 10 439 Epoxy composites, 10 450, 451 Epoxy compounds, photoinitiated polymerization of, 23 716 Epoxy content analysis, 10 385 Epoxy cresol novolac (ECN) resins, 10 367, 369... 

In subsequent work, Hamberg has reported that anerobic oxidation of lineolic acid by cumene hydroperoxide catalyzed hy sperm whale Mb results in formation of five products, the two major products being ll(i ,S)-hydroylinoleic acid (29% 5deld) and ( )cis-9,10-epoxy-(12Z)-octadecenoic acid (16%) (235). In this work, it was proposed that the second oxidizing equivalent required for substrate hydroxylation was probably provided by a protein-centered radical. 

It was reported earlier that strain ALA2 converted a-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 (Hosokawa et aL, 2003b). From product structures obtained from the co-3 PUFAs EPA and DHA, it seems that strain ALA2 places hydroxyl groups at similar positions from the omega (co)-terminal end of the substrates and cyclizes them to related THF ring structures, despite their increased total carbon chain lengths (by 2 and 4 carbons, respectively) and numbers of double bonds (by 1 and 2 respectively). 

According to the reports describing metabolic pathways involved in the conversion of linoleic acid to trihydroxy fatty acids, several intermediate reaction products, such as trihydroxy-, hydroperoxy-, dihydroxy-, and hydroxyepoxy-octadecenoate, were involved (Kato et al., 1984,1986). Those metabolites of linoleic acid showed distinct biological functions according to their intermediate structures, including mono-, di-, trihydroxy-octadecenoic acid, and hydroperoxy-, epoxy-forms (Kato et al., 1984 Blair, 2001 Gobel et al., 2002 Hou and Forman, 2000). In an effort to understand the overall mechanism involved in the varied biological functions of the complicated reaction metabolites of bio-converted polyunsaturated fatty acids, Kim et al. (2006) studied the oxidative activities on fish oil, of crude extracts produced by PR3 from... 

Fatty acids with trans or non-methylene-interrupted unsaturation occur naturally or are formed during processing for example, vaccenic acid (18 1 Hr) and the conjugated linoleic acid (CLA) rumenic acid (18 2 9tllc) are found in dairy fats. Hydroxy, epoxy, cyclopropane, cyclopropene acetylenic, and methyl branched fatty acids are known, but only ricinoleic acid (12(/f)-hydroxy-9Z-octadecenoic acid) (2) from castor oil is used for oleochemical production. OUs containing vernolic acid (12(5),13(/ )-epoxy-9Z-octadecenoic acid) (3) have potential for industrial use. 

As shown in Tables 9 and 10, on the basis of its high FD factor and its odor properties, the ira i-4,5-epoxy-tranj -2-decenal contributed significantly to the green, hay-like overall odor in soybean oil stored in the dark. Guth and Grosch suggested (13) that an epoxyhydroperoxy fatty acid could be the precursor of such epoxy aldehydes. Figure 8 shows the proposed pathway for the formation of frflni-4,5-epoxy-frani-2-decenal from linoleic acid via the tra i -12,13-epoxy-9-hydroperoxy-frani-lO-octadecenoic acid intermediate. 

Two rather interesting racemic syntheses for allylic methylated fatty acids have been recently accomplished [15]. One of these corresponds to the intriguing (12 )-11-methyl-12-octadecenoic acid (6), a marine bacterial fatty acid that in most reported identifications from natural sources has been shown to have the E double bond stereochemistry, but both Z,E isomers have been synthesized [15]. This mainly bacterial fatty acid was initially isolated from Byrsocarpus coccineus seed oil [16], but later it was reported in a bacterium associated with cat scratch disease [17], in Mycobacterium fallax [18], and most recently in a Pseudomonas sp. (.Alteromonas) associated with both the toxic dinoflagellate Ostreopsis lenticularis and several Caribbean Palythoa species [15]. More recently, acid 6 has been identified as an intermediate in the biosynthesis of the bacterial acid 10,13-epoxy-l l-methyloctadeca-10,12-dienoic acid, a furan fatty acid identified in several marine bacteria such as Shewanella putrefaciens [19-20]. 

Hamberg, M. and B. Gotthammar. 1973. A new reaction of unsaturated fatty acid hydroperoxides formation of 11-hydroxy-12,13-epoxy-9-octadecenoic acid from... 

The hydroxy group at the C-7 position was confirmed by C NMR chemical shift at 70.9 ppm and H NMR signals at 3.60 ppm (Table 2). Other C NMR chemical shifts and H NMR resonance patterns were very similar to those of 13,16-THFA. From these data, the structure of the product with GC Rt of 26 min was shown to be 7,13,16-trihydroxy-12, 15-epoxy-9-(Z)-octadecenoic acid (7,13,16-trihydroxy-THFA). 

A chemo-enzymatic enantiospecific synthesis of (S)-coriolic acid, (13S)-hy-droxy-18 2(9Z,ll ), mediated via immobilized alcohol dehydrogenase of baker s yeast has been described (31). 15,16-Didehydrocoriolic acid, 13-hydroxy-18 3(9Z, 11E, 15Z), was stereoselectively synthesized starting from pent-2-en-4-yn-1 -ol (32). Four stereoisomers of 9,10,13-trihydroxy-18 l(ll ) were derived from methyl 9,10-epoxy-12-octadecenoate. The latter was obtained by partial epoxidation of methyl linoleate. These trihydroxy C j g fatty acids are potential antirice blast fungal substances (33). (115)-Hydroxy-(125,13S)-epoxy-18 2(9Z,15Z) was synthesized from D-mannose (34). 

Another interesting oilseed crop tiiat has been researched in our laboratories for several years is Euphorbia lagascae (22) (Fig. 3). This oilseed crop contains vemolic acid (12,13 -epoxy-cis-9-octadecenoic acid), with a natural epoxide content of 65% (see Table 2). 

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