Oxidized fatty esters

Neff, W.E. and Frankel, E.N. Quantitative analyses of hydroxystearate isomers from hydroperoxides by high-pressure liquid chromatography of autoxidized and photosensi-tized-oxidized fatty esters. Lipids 15, 587-590 (1980). 

Two and twelve moles of ATP are produced, respectively, per mole of glucose consumed in the glycolytic pathway and each turn of the Krebs (citrate) cycle. In fat metaboHsm, many high energy bonds are produced per mole of fatty ester oxidized. Eor example, 129 high energy phosphate bonds are produced per mole of palmitate. Oxidative phosphorylation has a remarkable 75% efficiency. Three moles of ATP are utilized per transfer of two electrons, compared to the theoretical four. The process occurs via a series of reactions involving flavoproteins, quinones such as coenzyme Q, and cytochromes. 

Polymerization To a 5 liter glass reactor was added hydroxymethylated fatty esters and 625 molecular weight poly (ethylene oxide) triol initiator in a 6 1 molar ratio. 

Emulsifiers - [PROPYLENE OXIDE] (Vol 20) -m defoamers [DEFOAMERS] (Vol 7) -in dye baths [DYE CARRIERS] (Vol 8) -as food additives [FOOD ADDITIVES] (Vol 11) -in paint removers [PAINT - PAINT AND FINISH REMOVERS] (Vol 17) -m papermaking [PAPERMAKING ADDITIVES] (Vol 18) -for pesticides [PESTICIDES] (Vol 18) -frompolyammes [DIAMINESAND HIGITERAMINES ALIPITATIC] (Vol 8) -sorbitan fatty esters as [SUGAR ALCOHOLS] (Vol 23) -sulfonated mat ls for [SULFONATION AND SULFATION] (Vol 23) -use m cosmetics [COSMETICS] (Vol 7) -use m dairy substitutes [DAIRY SUBSTITUTES] (Vol 7)... 

The term non-ionic surfactant usually refers to derivatives of ethylene oxide and/or propylene oxide with an alcohol containing an active hydrogen atom. However other types such as alkyl phenols, sugar esters, alkanolamides, amine oxides, fatty acids, fatty amines and polyols are all produced and used widely throughout the world in a multitude of industries. This chapter covers the production of these materials and how they can be modified to meet the desired end product use. 

The hydrogenation of fatty acids or fatty esters is of industrial importance for the production of fatty alcohols. Usually, the hydrogenation is performed in slurry-phase or fixed-bed reactors over copper-chromium oxide catalyst at elevated temperature and pressure.37 Rieke et al. investigated the hydrogenation of methyl dodecanoate over copper-chromium oxide at 280°C and 13.8 MPa H2, in order to study the side reactions that occur during hydrogenation.37 On the basis of the potential reaction routes described by Rieke et al., the pathways leading to C12 alcohol and various byproducts are summarized in Scheme 10.2, with exclusion of the formation and reactions of acetals. It has been found that both catalytic activity and selectivity correlated well with the crystallinity of the copper-chromium ox-... 

The epoxidation of high-molecular-welght olefins (C,-C,) with peracetic acid In acetic acid solution Is accompanied by appreciable quantities of hydroxy acetoxy compounds, which arise by reaction of the oxides with the solvent. Similar treatment of the high-molecular-welght unsaturated fatty esters has been more successful. ... 

In order to explain the reason that marine oils are much more labile than common vegetable oUs, basic lipid chemistry, such as oxidation rate, induction period, and oxygen uptake were determined and reported by several researchers (70-72). The relative oxidation rates of fatty esters at 36.5°C were found to be highly... 

The number of double bonds in a fatty ester radical significantly affects both physical and chemical properties of the triacylglycerol. The highly unsaturated (three double bonds) linolenic acid (18 3) is unstable to oxidation, and undesirable odors and flavors can develop. The rate of oxidation 18 3 is 15-fold greater than that of oleic acid (18 1). 

CIC Green, fruity, fatty esters like (Z)-3-hexenyl butyrate, (Z)-3-hexenyl hexanoate, 2-ethyl hexenoate, 2-ethyl-octenoate form the basic fruity body. Nerol oxide and edulan add an ethereal, fresh, green, sharp, floral topnote. The floral note (mainly in the purple variety) is represented by linalool with a complex of ionone derivatives, mainly beta-ionone, dihydro-beta-ionone, theaspirone, damascenone. The key components for the green, exotic, sulfury topnote of the yellow variety are 2-methyl-4-propyl-l,3-oxathiane and 3-methylthio-l-hexanol. 

HPLC has also been applied to the analysis of trimethylolpropane and pentaerythritols in industrial synthesis solutions, 2-mercaptobenzothiazole in waste dump effluent, polythionates in mining waste water, isocyanates in working atmospheres, carcinogenic amines, aniline in waste water, polyethylene oxide fatty acid surfactants in industrial process waters and phthalate esters in river water. 

In recent years, besides other bimetallic systems (PdRe, ReSn, RhSn, CoSn) Ru-Sn/AbOs catalysts have gained much attention in studying the hydrogenoly-sis of fatty esters to fatty alcohols. It has been proposed that in the hydro-genolysis of fatty esters the active centers are metallic Ru particles in interaction with tin oxide acting as Lewis acid centers involved in the activation of the carbonyl group. °... 

The authors of this review have found that the origin, composition and treatments of CuO-ZnO-AhOa commercial and laboratory-made catalysts strongly affected their phase composition and average crystallite sizes of CuO in the oxide form and Cu in the reduced form of catalysts, respectively. Catalytic activity and selectivity data obtained on laboratory-made catalysts suggests that co-precipitation provides intimate contact between copper and zinc resulting in the formation Cu -Cu ensembles sites that are active in the hydrogenolysis of fatty esters to alcohol. In agreement with literature data ZnO may play a role in the formation and stabilization of metal ion-metal nanoparticle ensemble sites. 

The PEGs themselves show little surface activity, but when converted to mono- and diesters by reaction with fatty acids, they form a series of widely useful nonionic surfactants. The required balance of hydrophilic-hydrophobic character can be achieved by suitable combination of the molecular weight of the PEG and the nature of the fatty acid. For large-volume items a second production route of direct addition of ethylene oxide to the fatty acids is often preferred. End uses for the fatty esters are largely as textile lubricants and softeners and as emulsifiers in food products, cosmetics, and pharmaceuticals. 

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