- Isolation of 9-hydroxy-10E,12Z-octadecadienoic acid, an inhibitor of fat accumulation from Valeriana fauriei
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An EtOH extract of Valeriana fauriei was found to exhibit potent inhibition of fat accumulation against 3T3-L1 murine adipocytes. After performing several chromatographic steps, we successfully isolated the conjugated linoleic acid derivative, 9-hydroxy-10E,12Z-octadecadienoic acid (9-HODE). Synthesized 9-HODE and its analogs showed inhibitory activity against fat accumulation.
- Yuki, Keiji,Ikeda, Mariko,Miyamoto, Kenji,Ohno, Osamu,Yamada, Kaoru,Uemura, Daisuke
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body text
p. 1233 - 1235
(2012/10/07)
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- Quantitation of hydroperoxy-, keto- and hydroxy-dienes during oxidation of FAMEs from high-linoleic and high-oleic sunflower oils
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The objective of this work was to study the quantitative formation of hydroperoxydienes, ketodienes and hydroxydienes during autoxidation at 40 °C of fatty acid methyl esters derived from two sunflower oils with different degree of unsaturation, high-linoleic sunflower oil and high-oleic sunflower oil. The analysis of the oxidation compounds was carried out by NP-HPLC-UV and results were compared to the specific extinction at 232 nm (K 232) and the peroxide value (PV). Analysis of FAME polymers by HPSEC was also performed to discard samples of advanced oxidation. Results showed that the contents of hydroperoxydienes with respect to the PV were higher for the high linoleic (HL) sample. At the end of the period of slow polymerization (ΔPol ≤ 1 wt%), the content of hydroperoxydienes was found to be 86.0 and 30.7 μg/mg for the HL and high oleic (HO) samples, respectively. Throughout this period, hydroperoxydienes constituted around 90 and 50 wt% of the total hydroperoxides in the HL and HO samples, respectively, suggesting that a significant oxidation of oleic acid also occurred in both samples. The contents of ketodienes and hydroxydienes as a whole constituted 2-3 wt% of the diene compounds analyzed at the end of the period of slow polymerization. Higher contents of ketodienes than of hydroxydienes were found throughout the oxidation time, and the ratio between the contents of ketodienes and hydroxydienes increased with a factor that changed from 1 to 2 throughout the period of slow polymerization.
- Morales, Arturo,Dobarganes, Carmen,Marquez-Ruiz, Gloria,Velasco, Joaquin
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experimental part
p. 1271 - 1279
(2011/08/21)
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- Synthesis and biological activity of hydroxylated derivatives of linoleic acid and conjugated linoleic acids
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Allylic hydroxylated derivatives of the C18 unsaturated fatty acids were prepared from linoleic acid (LA) and conjugated linoleic acids (CLAs). The reaction of LA methyl ester with selenium dioxide (SeO2) gave mono-hydroxylated derivatives, 13-hydroxy-9Z,11E-octadecadienoic acid, 13-hydroxy-9E,11E-octadecadienoic acid, 9-hydroxy-10E,12Z-octadecadienoic acid and 9-hydroxy-10E,12E-octadecadienoic acid methyl esters. In contrast, the reaction of CLA methyl ester with SeO2 gave di-hydroxylated derivatives as novel products including, erythro-12,13-dihydroxy-10E-octadecenoic acid, erythro-11,12-dihydroxy-9E-octadecenoic acid, erythro-10,11-dihydroxy-12E-octadecenoic acid and erythro-9,10-dihydroxy-11E-octadecenoic acid methyl esters. These products were purified by normal-phase short column vacuum chromatography followed by high-performance liquid chromatography (HPLC). Their chemical structures were characterized by liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (NMR). The allylic hydroxylated derivatives of LA and CLA exhibited moderate in vitro cytotoxicity against a panel of human cancer cell lines including chronic myelogenous leukemia K562, myeloma RPMI8226, hepatocellular carcinoma HepG2 and breast adenocarcinoma MCF-7 cells (IC50 10-75 μM). The allylic hydroxylated derivatives of LA and CLA also showed toxicity to brine shrimp with LD50 values in the range of 2.30-13.8 μM. However these compounds showed insignificant toxicity to honeybee at doses up to 100 μg/bee.
- Li, Zhen,Tran, Van H.,Duke, Rujee K.,Ng, Michelle C.H.,Yang, Depo,Duke, Colin C.
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experimental part
p. 39 - 45
(2010/03/31)
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- Properties of a mini 9R-lipoxygenase from Nostoc sp. PCC 7120 and its mutant forms
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Lipoxygenases (LOXs) consist of a class of enzymes that catalyze the regio- and stereospecific dioxygenation of polyunsaturated fatty acids. Current reports propose that a conserved glycine residue in the active site of R-lipoxygenases and an alanine residue at the corresponding position in S-lipoxygenases play a crucial role in determining the stereochemistry of the product. Recently, a bifunctional lipoxygenase with a linoleate diol synthase activity from Nostoc sp. PCC7120 with R stereospecificity and the so far unique feature of carrying an alanine instead of the conserved glycine in the position of the sequence determinant for chiral specificity was identified. The recombinant carboxy-terminal domain was purified after expression in Escherichia coli. The ability of the enzyme to use linoleic acid esterified to a bulky phosphatidylcholine molecule as a substrate suggested a tail-fist binding orientation of the substrate. Site directed mutagenesis of the alanine to glycine did not cause alterations in the stereospecificity of the products, while mutation of the alanine to valine or isoleucine modified both regio- and enantioselectivity of the enzyme. Kinetic measurements revealed that substitution of Ala by Gly or Val did not significantly influence the reaction characteristics, while the A162I mutant showed a reduced vmax. Based on the mutagenesis data obtained, we suggest that the existing model for stereocontrol of the lipoxygenase reaction may be expanded to include enzymes that seem to have in general a smaller amino acid in R and a bulkier one in S lipoxygenases at the position that controls stereospecificity.
- Andreou, Alexandra-Zoi,Vanko, Marian,Bezakova, Lydia,Feussner, Ivo
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p. 1832 - 1837
(2008/09/20)
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- Antioxidant activity of the new thiosulfinate derivative, S-benzyl phenylmethanethiosulfinate, from Petiveria alliacea L.
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The antioxidant effects of the new thiosulfinate derivative, S-benzyl phenylmethanethiosulfinate (BPT), against the oxidation of cumene and methyl linoleate (ML) in chlorobenzene were studied in detail using HPLC. The results showed that BPT provided effe
- Okada, Youji,Tanaka, Kaoru,Sato, Eisuke,Okajima, Haruo
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experimental part
p. 1097 - 1102
(2009/02/05)
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- Characterization and quantification of free and esterified 9- and 13-hydroxyoctadecadienoic acids (HODE) in barley, germinating barley, and finished malt
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The analysis of (R)-9- and (S)-9-hydroxy-10E,12Z-octadecadienoic acid as well as (R)-13- and (S)-13-hydroxy-9Z,11E-octadecadienoic acid (HODE) as free acids, esterified in triacylglycerols (storage lipids), and esterified in polar lipids (phospholipids, glycolipids, etc.) in barley, germinating barley, and finished malt was performed using [13-18O1]-(S)-13-HODE isotope dilution assays with GC-MS and straight- and chiral-phase HPLC. 9- and 13-HODE occur approximately racemically in barley, indicating an autoxidation. The enantiomeric excesses increase to 78% S for free 9-HODE and to 58% S for free 13-HODE in germinating barley as a result of lipoxygenase-2 (LOX-2) catalysis, but free HODEs are at low concentration. More than 90% of HODEs in barley and malt are esterified. In the storage lipids of green malt 53 mg/kg 9-HODE and 147 mg/kg 13-HODE were detected. This ratio of 30:70 reflects the regioselectivity of the LOX-2 enzyme in malt. In the polar lipids 45 mg/kg 9-HODE and 44 mg/kg 13-HODE were characterized. The latter indicate a hitherto unknown 9-lipoxygenase activity with polar lipids as substrates. During kilning the contents of most HODEs decreased significantly due to chemical and enzymatic degradation, whereas polar-esterified (R)-13-HODE increased (43%) in the finished malt.
- Hobke, Holger,Garbe, Leif-Alexander,Tressl, Roland
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p. 1556 - 1562
(2007/10/03)
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- Easy access to various natural keto polyunsaturated fatty acids and their corresponding racemic alcohols
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Various optically active hydroxy derivatives of polyunsaturated fatty acids were easily oxidised to their corresponding keto derivatives using Dess-Martin periodinane. The reaction was run on the millimolar scale with good yields and without appreciable isomerisation of the surrounding double bonds. Reduction of these keto compounds to yield back the starting alcohols, but now as racemic mixtures, was also conducted using CeCl3-NaBH 4, once again without noticeable modification of the stereochemistry of the double bonds. These reactions proved the usefulness of the chemoenzymatic access to oxylipins through the use of lipoxygenases with various regiospecificity, combined with chemical transformations of the formed hydro(pero)xides.
- Iacazio, Gilles
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p. 115 - 121
(2007/10/03)
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- Preparation of the enantiomers of hydroxy-C18 fatty acids and their anti-rice blast fungus activities
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In order to examine the correlation between the anti-rice blast fungus activity and the chirality of allylic alcohols 1-3, which were characterized from the infected rice plants as an enantiomeric mixture with 10% e.e., a procedure for the chemical prepa
- Kato, Tadahiro,Nakai, Toshio,Ishikawa, Rumiko,Karasawa, Aya,Namai, Tsuneo
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p. 2695 - 2701
(2007/10/03)
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- Peroxidations initiated by lignin model compounds: Investigating the role of singlet oxygen in photo-yellowing
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3,5-Di-tert-butyl-ortho-quinone, 6, and 1-(3,4-dimethoxyphenyl-2-(2-methoxyphenoxy)-1-propanone, 7, models for oxidized lignin and for lignin, were used as sensitizers of photo-oxidation. Product studies by HPLC from oxidation of methyl linoleate in solution sensitized by 6 or 7, and in sodium dodecyl sulfate (SDS) sensitized by 6, showed a product distribution of six hydroperoxides, the four conjugated 9- and 13-hydroperoxides of the geometrical isomers: trans-10, cis-12 (2), cis-9, trans-11 (3), trans-10, trans-12 (4), and trans-9, trans-11 (5)-octadecadienoates plus two nonconjugated hydroperoxides. The higher cis/trans to trans/trans (ct/tt) of geometrical isomers (2 + 3//4 + 5) compared to ct/tt from known thermal free-radical peroxidations (Type 1) indicate that singlet oxygen (Type 2) oxidation occurs in reactions sensitized by 6 or 7. Kinetic studies by oxygen uptake are reported on oxidations of hydrocarbons 1-phenyl-2-methylpropene, 8, and trans-stilbene, 9, sensitized by the quinone, 6, or by a dye, Rose Bengal. Quenching studies imply singlet oxygen reactions. Milled wood lignin undergoes self-initiated photo-oxidation in water, and oxygen uptake was quenched by sodium azide. Cellobiose, a cellulose model, undergoes sensitized photooxidation using model quinone, 6, in a mixture of tert-butyl alcohol and water or using the sensitizers benzophenone or the lignin model, 7, delivered on a solid support, silica gel, and these oxidations were quenched with sodium azide. These results implicate singlet oxygen in the photo-yellowing of high lignin content wood pulps.
- Barclay, L. Ross C.,Grandy, Jennifer K.,MacKinnon, Heather D.,Nichol, Heather C.,Vinqvist, Melinda R.
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p. 1805 - 1816
(2007/10/03)
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- Synthesis of keto- and hydroxydienoic compounds from linoleic acid
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A convenient preparative method has been developed for the synthesis of hydroxydienoic (9-HODE and 13-HODE) and ketodienoic compounds (9-KODE and 13-KODE) from natural linoleic acid. Methyl linoleate was treated with 1.25 eq. of m-chloroperbenzoic acid in alcoholic solution, giving a mixture of mono-epoxides (yield 60%), that was treated with a solution of HBr in MeOH to yield a mixture of the bromohydrins (yield 92%). The last was oxidized by Jones reagent to a mixture of bromoketones (yield 64%) and the mixture obtained was dehydrobrominated by DBU to produce a mixture of ketodienoic compounds (yield 94%). Reduction of the ketodienoic compounds by KBH4 in MeOH led to the corresponding hydroxydienoic (9-HODE and 13-HODE) methyl esters (yield 83%). The synthetic approach described is simple and gives reliable results. The keto- and hydroxy fatty acids obtained were characterized thoroughly by TLC, HPLC, UV, FT-IR, 1H-, 1H1H- and 13C-NMR.
- Kuklev, Dmitry V.,Christie, William W.,Durand, Thierry,Rossi, Jean Claude,Vidal, Jean Pierre,Kasyanov, Sergey P.,Akulin, Valery N.,Bezuglov, Vladimir V.
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p. 125 - 134
(2007/10/03)
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- Identification and quantification of the regioisomeric cholesteryl linoleate hydroperoxides in oxidized human low density lipoprotein and high density lipoprotein
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Oxidation of human LDL is implicated as an initiatior of atherosclerosis. Isolated low density lipoprotein (LDL) and high density lipoprotein (HDL2) were exposed to aqueous radicals generated from the thermolabile azo compound 2,2'-azobis(2-amidinopropane) dihydrochloride. The primary nonpolar lipid products formed from the autoxidation of LDL and HDL were the regioisomeric cholesteryl linoleate hydroperoxides. In LDL oxidations, 9- and 13- hydroperoxides with trans,cis conjugated diene were formed as the major oxidation products if endogenous α-tocopherol was present in the LDL. After extended oxidation of LDL, at the time when endogenous α-tocopherol was consumed, the two trans,cis conjugated diene hydroperoxides began to disappear and the 9- and 13-hydroperoxides with trans,trans conjugated diene appeared. At very long oxidation times, none of the primary products, the conjugated diene hydroperoxides, were present. In HDL2, which has only very low levels of antioxidants, both the 9- and 13-hydroperoxides with trans,cis conjugated diene and the 9- and 13-hydroperoxides with trans,trans conjugated diene were formed at early stages of oxidation. The corresponding alcohols were also formed in the HDL2 oxidations. A mechanistic hypothesis consistent with these observations is presented.
- Kenar, James A.,Havrilla, Christine M.,Porter, Ned A.,Guyton, John R.,Brown, Spencer A.,Klemp, Keith F.,Selinger, Elizabeth
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p. 737 - 744
(2007/10/03)
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- High-Performance Liquid Chromatographic Analysis of the Products of Linoleic Acid Oxidation Catalyzed by Pea (Pisum sativum) Seed Lipoxygenases
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An HPLC method is discussed for the analysis of the products formed by the pea (Pisum sativum) lipoxygenase catalyzed oxidation of linoleic acid.The results demonstrate the feasibility of analyzing all of the hydroperoxides, hydroxides, and keto fatty acids in a single chromatographic step and show that it will be possible to analyze the product profile from the lipoxygenase activity contained in a portion of a seed, which will permit the remainder of the seed to be grown on for subsequent generations.The chemical structures of the products have been identified by HPLC analysis and GC-MS. Keywords: Lipoxygenase; hydroperoxides; chromatography
- Wu, Zecai,Robinson, David S.,Domoney, Claire,Casey, Rod
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p. 337 - 342
(2007/10/02)
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- Oxygenated Fatty Acids with Anti-rice Blast Fungus Activity in Rice Plants
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Expecting that the different characteristics of rice plants against rice blast fungus, that is, susceptibility of the weaker cultivar, Sasanishiki and resistance of the stronger cultivars, Fukuyuki and Fukunishiki, may be due to the absence or presence of anti-fungus compounds in the rice plants, the anti-rice blast fungus substances in these three kinds of rice plants were explored.We found five epoxides and five allyl alcohols as anti-rice blast fungus compounds.The epoxides were 12,13-epoxy- and 9,10-epoxylinoleic acids, and 15,16-epoxy-, 12,13-epoxy-, and 9,10-epoxylinolenic acids.The allyl alcohols are 13-hydroxy and 9-hydroxy linoleic acids, and 16-hydroxy, 13-hydroxy, and 9-hydroxy linolenic acids.In inoculated Sasanishiki, the activity is due to the formation of the allyl alcohols.
- Kato, Tadahiro,Yamaguchi, Yoshihiro,Namai, Tsuneo,Hirukawa, Toshifumi
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p. 283 - 287
(2007/10/02)
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- IRON-PEPLOMYCIN CATALYZED OXYGENATION OF LINOLEIC ACID
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Incubation of linoleic acid with Fe(III)-peplomycin under aerobic conditions produced a mixture of hydroperoxides 1a-d as primary products which then gave rise to the formation of the corresponding dienones (2a-d), alcohols (3a-d) and epoxyenones (4a,b).
- Nagata, Ryu,Morimoto, Shinji,Saito, Isao
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p. 4485 - 4488
(2007/10/02)
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- STRUCTURE AND SYNTHESIS OF 11,12,13-TRIHYDROXY-9Z,15Z-OCTADECADIENOIC ACIDS FROM RICE PLANT SUFFERING FROM RICE BLAST DISEASE
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Structural elucidation including the absolute configuration was carried out on the trihydroxyoctadecadienoic acids isolated from rice plant suffering from rice blast disease.
- Kato, Tadahiro,Yamaguchi, Yoshihiro,Ohnuma, Shin-ichi,Uyehara, Tadao,Namai, Tsuneo,etc.
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p. 577 - 580
(2007/10/02)
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- APPLICATION OF FURAN OXIDATIONS IN SYNTHESIS: TOTAL SYNTHESIS OF (+/-)-COROLIC ACID
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As a general synthesis approach to compounds containing the cis-trans allylhydroxy functionality ( subunit A), an appropriately substituted furan nucleus is oxidatively cleaved to provide an unsaturated 1,4-dicarbonyl moiety suitably disposed for further elaboration.The total synthesis of (+/-)-coriolic acid demonstrates the utility of the approach.
- Gunn, Bruce P.
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p. 3061 - 3067
(2007/10/02)
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- UNSATURATED HYDROXY FATTY ACIDS, THE SELF DEFENSIVE SUBSTANCES IN RICE PLANT AGAINST RICE BLAST DISEASE
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In addition to the previously described epoxy fatty acids, five hydroxy fatty acids were characterized as self defensive substances produced in the rice plant against rice blast disease.
- Kato, Tadahiro,Yamaguchi, Yoshihiro,Hirano, Takumi,Yokoyama, Toshiro,Uyehara, Tadao,et al.
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p. 409 - 412
(2007/10/02)
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