Fatty acids epoxy

Plants were probably the first to have polyester outerwear, as the aerial parts of higher plants are covered with a cuticle whose structural component is a polyester called cutin. Even plants that live under water in the oceans, such as Zoestra marina, are covered with cutin. This lipid-derived polyester covering is unique to plants, as animals use carbohydrate or protein polymers as their outer covering. Cutin, the insoluble cuticular polymer of plants, is composed of inter-esterified hydroxy and hydroxy epoxy fatty acids derived from the common cellular fatty acids and is attached to the outer epidermal layer of cells by a pectinaceous layer (Fig. 1). The insoluble polymer is embedded in a complex mixture of soluble lipids collectively called waxes [1], Electron microscopic examination of the cuticle usually shows an amorphous appearance but in some plants the cuticle has a lamellar appearance (Fig. 2). 

The aliphatic components of SOM, derived from various sources, tend to persist in soil (Almendros et al. 1998 Lichtfouse et al. 1998a Lichtfouse et al. 1998b Mosle et al. 1999 Poirier et al. 2000). The principal source of aliphatic materials in soil is plant cuticular materials, especially cutin, an insoluble polyester of cross-linked hydroxy-fatty acids and hydroxy epoxy-fatty acids (Kolattukudy 2001). Some plant cuticles also contain an acid and base hydrolysis-resistant biopolymer, comprised of aliphatic chains attached to aromatic cores known as cutan (Tegelaar et al. 1989 McKinney et al. 1996 Chefetz 2003 Sachleben et al. 2004). 

In addition to the unfunctionalized alkene epoxides discussed in the previous subsection, various other types of epoxides exist that are also derived from unconjugated alkenes but that share two additional features, i. e., being characterized by the presence of one or more functional group(s) and having biological significance. Thus, the present subsection examines epoxy alcohols, epoxy fatty acids, allylbenzenes 2, 3 -oxides, as well as alkene oxide metabolites of a few selected drugs. 

J. F. Greene, J. W. Newman, K. C. Williamson, B. D. Hammock, Toxicity of Epoxy Fatty Acids and Related Compounds to Cells Expressing Human Soluble Epoxide Hydrolase , Chem. Res. Toxicol. 2000, 13, 217 - 226. 

Epoxy-fatty acid adduct Reaction product of fatty acid with DGEBA MW = ca. 880 f > 4 r > 1.7. 

Studies on the biosynthesis of lactones have shown that epoxidation of unsaturated fatty acids like, e.g., linoleic and linolenic acid may represent a common pathway to oxygenated derivatives of fatty acids. Epoxy fatty acid hydrolases were identified as key enzymes that exhibit high regioselectivity and enantiose-lectivity [25, 26]. 

Conventional breeding has developed oilseed rape (Brassica napus) cultivars that can accumulate long-chain fatty acids such as C20 1 and C22 l, however the ability to accumulate short-chain fatty acids is limited. Similarly the ability to accumulate industrially useful hydroxy fatty acids and epoxy fatty acids is also limited with conventional breeding methods. Due to its close relationship to the crucifer Arabidopsis and its associated characterised genome, and the relative ease with which genes can be inserted into Brassica species, oilseed rape is seen as a key target species for genetic manipulation. 

Epoxy fatty acids affect hormone secretion... 

Cutinases are hydrolytic serine esterases that degrade cntin, a polyester of hydroxy and epoxy fatty acids (Purdy and Kolattukudy, 1975) and specific for primary alcohol esters (Murphy et al., 1996). The fatty acids of cutin are usually n-C16 and -C18 oxygenated hydroxyacids (containing one to three hydroxyl gronps). Cntins are lipid-based polymers of plants and ester bonds dominate in the cutins. Therefore, cntinases... 

Vemolic acid (or c -12,13-epoxy-octadec-cA-9-enoic acid) (Fig. 6) was the hrst naturally occurring epoxy fatty acid isolated from the seed oil of Vernonia anthelmintica. It is also found in several Compositae, Malvaceae, and Euphorbiaceae species in signihcant amounts. Other epoxy acids include... 

Many of the biological actions of essential fatty acids are the result of their metabolic products, the eicosanoids. These are oxidized derivatives of AA and include prostaglandins and thromboxanes that are formed via the cyclo-oxygenase (COX) pathway, as well as hydroxy fatty acids and leukotrienes that arise by means of the lipoxygenase pathway. Another series of AA-derived products, the epoxy fatty acids, are produced by the cytochrome P450 epoxygenase pathway. The AA that serves as precursor for these reactions... 

Keto-fatty acids may be prepared conventionally by epoxidation of unsaturated fatty acids and isomerisation of the prepared epoxy fatty acids [21]. In contrast, we directly oxidized the unsaturated fatty acids to methylketo-fatty acids. 

Fang, X., T.L. Kaduce, M. VanRollins, N.L. Weintraub, and A.A. Specter (2000). Conversion of epoxyeicosatrienoic acids (EETs) to chain-shortened epoxy fatty acids by human skin fibroblasts. J. Lipid Res. 41, 66-74. 

Sharma, B.K. K.M. Doll S.Z. Erhan. Oxidation, friction reducing, and low temperature properties of epoxy fatty acid methyl esters. Green Chem. 2007a, 9, 469-474. 

Accumulation of Epoxy Fatty Acids in Plant Oils... 

The biochemical reaction catalyzed by epoxygenase in plants combines the common oilseed fatty acids, linoleic or linolenic acids, with O2, forming only H2O and epoxy fatty acids as products (CO2 and H2O are utilized to make linoleic or linolenic acids). A considerable market currently exists for epoxy fatty acids, particularly for resins, epoxy coatings, and plasticizers. The U.S. plasticizer market is estimated to be about 2 billion pounds per year (Hammond 1992). Presently, most of this is derived from petroleum. In addition, there is industrial interest in use of epoxy fatty acids in durable paints, resins, adhesives, insecticides and insect repellants, crop oil concentrates, and the formulation of carriers for slow-release pesticides and herbicides (Perdue 1989, Ayorinde et al. 1993). Also, epoxy fatty acids can readily and economically be converted to hydroxy and dihydroxy fatty acids and their derivatives, which are useful starting materials for the production of plastics as well as for detergents, lubricants, and lubricant additives. Such renewable derived lubricant and lubricant additives should facilitate use of plant/biomass-derived fuels. Examples of plastics that can be produced from hydroxy fatty acids are polyurethanes and polyesters (Weber et al. 1994). As commercial oilseeds are developed that accumulate epoxy fatty acids in the seed oil, it is likely that other valuable products would be developed to use this as an industrial chemical feedstock in the future. 

Hammond, E. 1992. Oil Usedfor Industrial Products. Special Report 92 of the Iowa Agriculture and Home Economics Experiment Station, Iowa State University Press, Ames, lA. Hatanaka, T., and D. Hildebrand. 2001. Expression of epoxy fatty acid synthesis genes. ASPB meeting abstract presentation. Providence, RI. http //abstracts.aspb.org/aspp2001/public/ P38/0735.html. 

Seither, C. 1997. Characterization of epoxy fatty acid synthesis in Vemonia galamensis and the isolation of candidate cDNA clones. Master s thesis. University of Kenmcky, Lexington. 

Gaboon EB, Ripp KG, Hall SE, McGonigle B. (2002) Transgenic production of epoxy fatty acids by expression of a cytochrome P450 enzyme from Euphorbia lagascae seed. Plant Physiol 128 615-624. 

C.jHjjO, Mr 296.45, mp. 32.5 °C, [alg +2.03° (hexane), soluble in organic solvents. V. occurs in large amounts (60- 80%) as glycerol esters in the seed oils of Vemonia anthelmintica and V. galamensis (Astera-ceae) as well as Euphorbia lagascae (Euphorbiaceae). V. and other epoxy fatty acids are toxic compounds ... 

The walnut oil used in our study contained 26 6 mg naturally occurring hydroxy fatty acids. After the meal, plasma concentration of these unlabeled hydroxy fatty acids increased by 100% (from 0.54 0.07 to 1.09 0.24 imol/L, P < 0.05). One should realize that the calculation of absorption of the [U- C]-labeled hydroxy- or epoxy-fatty acids is based on the assumption that hydroxy TG are metabolized, transported in chylomicrons, and incorporated into VLDL as any other long-chain fatty acid (37). This may not be true. Less oxidized linoleic acid was incorporated into chylomicrons in CaCo-2 epithelial cells in culture (40). Thus, we may have underestimated the extent of absorption. Nevertheless, an important conclusion is that the more fat that is oxidized, the less there is to be absorbed. 

The endothelial dysfunction during the postprandial phase after a meal rich in oxidized fat is almost certainly due to the cellular response to oxidized fat originating from this repeatedly heated fat. As in so many cases, the precise identity of this factor is not known. It is often assumed that it is a reactive molecule, derived from quantitatively the most important unsaturated fatty acid (linoleic acid) in the diet. Thus 9-, 11-, and 13-hydroperoxy-linoleic acids are possibilities, as are 8,9- or 11,12-epoxy-linoleic acids. However, the relative amount of epoxy fatty acids in the diet is much less than that of hydroperoxy fats. Photooxidation products of oleic acid cannot be excluded either, and it is worth pointing out that this unsaturated fatty acid is quantitatively the most important fatty acid in Western and Mediterranean diets. What is also not clear is whether endothelial dysfunction during postprandial lipemia requires the induction of enzymes. 

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