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1

40 CFR 721.3100 - Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine.  

Code of Federal Regulations, 2010 CFR

... Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine. 721.3100 Section 721.3100 Protection... Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine. (a) Chemical substance and significant...

2009-07-01

2

40 CFR 721.3100 - Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine.  

Code of Federal Regulations, 2010 CFR

... Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine. 721.3100 Section 721.3100 Protection... Oligomeric silicic acid ester compound with a hy-droxyl-al-kyla-mine. (a) Chemical substance and significant...

2010-07-01

3

Isolation of pure natural linoleic and linolenic acids as their methyl esters by adsorption fractionation on silicic acid  

Microsoft Academic Search

SummaryAn effective procedure is described for fractionating methyl esters of oils rich in linoleic and linolenic acids by adsorption\\u000a on silicic acid columns. Pure methyl linoleate from methyl esters of tobacco seed oil and pure methyl linolenate from methyl\\u000a esters of linseed and perilla oils were isolated by this procedure. These compounds were characterized by the usual physical\\u000a and chemical

R. W. Riemenschneider; S. F. Herb; Peter L. Nichols

1949-01-01

4

40 CFR 721.3635 - Octadecanoic acid, ester with 1,2-propanediol, phosphate, anhydride with silicic acid (H4SiO4).  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Octadecanoic acid, ester with 1,2-propanediol, phosphate, anhydride with silicic acid (H4SiO4). 721.3635 Section 721...Substances § 721.3635 Octadecanoic acid, ester with 1,2-propanediol,...

2013-07-01

5

Fumaric acid esters  

Microsoft Academic Search

Several clinical studies have shown that systemic therapy with fumaric acid esters (FAEs) in patients with moderate to severe psoriasis is effective and has a good long-term safety profile. For therapeutic use, tablets with a defined mixture of FAEs (dimethylfumarate [DMF] and three different salts of monoethylfumarate) are registered in Germany. There is evidence that DMF is the most essential

Martin Rostami Yazdi; Ulrich Mrowietz

2008-01-01

6

Method for deeper penetrating acidizing of siliceous formations  

SciTech Connect

A method for acidizing siliceous subterranean formations wherein the acidizing composition penetrates the formation to a greater extent before spending comprising injecting into the formation first an organosilane or an ester of an organosilane, preferably in a hydrocarbon carrier liquid, and thereafter an aqueous acidizing composition containing a non-oxidizing mineral acid, acid precursor, low molecular weight organic acid or halogenated derivative thereof, and a fluorine-containing acid or salt.

Kalfayan, L. J.

1984-10-30

7

Esters of Aromatic Sulfonic Acids.  

National Technical Information Service (NTIS)

Novel esters of aromatic sulfonic acids are disclosed. The specific esters are nitrophenyl p- and m- amidinophenylmethane-sulfonate. Also disclosed is a method for specific inactivation of the enzyme, thrombin, employing nitrophenyl p-amidinophenyl-methan...

Wong Shaw

1976-01-01

8

Silicic acid: boric acid complexes as wood preservatives  

Microsoft Academic Search

Wood was treated with a low molecular-weight silicic acid: boric acid agent and examined for increased resistance to termites and combustion. Wood treated with silicic acid only exhibited increased termite resistance, but not to the marked extent observed after treatment with a mixture of silicic and boric acids. Increasing the quantity of boric acid also increased the termite mortality rate

Haruhiko Yamaguchi

2003-01-01

9

Fumaric acid esters.  

PubMed

Several clinical studies have shown that systemic therapy with fumaric acid esters (FAEs) in patients with moderate to severe psoriasis is effective and has a good long-term safety profile. For therapeutic use, tablets with a defined mixture of FAEs (dimethylfumarate [DMF] and three different salts of monoethylfumarate) are registered in Germany. There is evidence that DMF is the most essential component in this formulation with an antipsoriatic effect. Currently, there are few data on the pharmacokinetics of fumarates in human beings. DMF seems to act as a prodrug for its main metabolite: monomethylfumarate. This hypothesis was supported by the observation that only monomethylfumarate was detected in the plasma of human beings after the oral administration of FAEs. FAEs have been tested in different biological assays, and effects such as inhibition of the nuclear factor kappa B pathway or induction of apoptosis by DMF have been described. For these data, the role of DMF as a modulator of intracellular glutathione plays an important role. PMID:18755371

Rostami Yazdi, Martin; Mrowietz, Ulrich

10

Methyl esters in the fatty acid industry  

Microsoft Academic Search

Methyl esters, derived from natural fats or oils, can be used as alternatives to fatty acids in the production of a number\\u000a of derivatives. The derivatives that can be made from methyl esters include fatty alkanolamides, fatty alcohols, isopropyl\\u000a esters, and sucrose polyesters. By using methyl esters as the raw materials, several benefits may be realized, such as, the\\u000a ability

R. D. Farris

1979-01-01

11

Method for acidizing siliceous formations  

SciTech Connect

A method is described for treating a subterranean formation surrounding a wellbore which comprises injecting into the formation an aqueous acidizing solution. The aqueous acidizing solution contains hydrofluoric acid and excess fluoride. The excess fluoride is present in an amount greater than the amount of fluoride stoichiometrically required to form hydrofluoric acid, and thereafter fluids are produced from the wellbore.

Lamb, W.J.; Kunze, K.R.

1987-03-10

12

Quantitative separations of higher fatty acid methyl esters by adsorption chromatography on silica impregnated with silver nitrate  

Microsoft Academic Search

A chromatographic adsorbent has been developed for the separation of geometric isomers of fatty acid methyl esters. The adsorbent\\u000a consists of silicic acid impregnated with silver nitrate.\\u000a \\u000a Quantitative separations of saturated,cis-, andtrans-monoenoic and polyenoic methyl esters in 30 to 100 mg quantities are reported.

B. De Vries

1963-01-01

13

40 CFR 721.10125 - Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and alkenoic acid...  

Code of Federal Regulations, 2010 CFR

... Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle... Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle...as alkenedioic acid, dialkyl ester, reaction products with...

2009-07-01

14

Thermoset polymer-layered silicic acid nanocomposites  

NASA Astrophysics Data System (ADS)

Nanocomposites are formed when phase mixing occurs on a nanometer length scale. Due to the improved phase morphology and interfacial properties, nanocomposites exhibit mechanical properties superior to conventional composites. Toyota researchers first demonstrated that organoclay could be exfoliated in a nylon-6 matrix to greatly improve the thermal and mechanical properties of the polymer, which has resulted in a practical application in the automobile industry. A great deal of research has been conducted on organic-inorganic hybrid composites in which smectite clays are used as reinforcement agents. However, little work has been devoted to derivatives of other layered inorganic solids. In the present work, the first examples of organic polymer-layered silicic acid nanocomposites have been prepared by formation of a cured epoxy polymer network in the presence of organo cation exchange forms of magadiite. The exfoliation of silicate nanolayers in the epoxy matrix was achieved by in-situ intragallery polymerization during the thermosetting process. In general, the tensile properties, solvent resistance, barrier properties and chemical stability of the polymer matrix are greatly improved by the embedded silicate nanolayers when the matrix is flexible (sub-ambient Tg). The improvement of properties are dependent on the silicate loading, the degree of nanolayer separation and interfacial properties. Interestingly, the exfoliation also affects the polymer elasticity in a favorable way. The mechanism leading to nanocomposite formation is proposed. One exfoliated epoxy-magadiite nanocomposite/composition possessed unique transparent optical properties. The exfoliation chemistry was successfully extended to the other members of the layered silicic acid family. A new approach also was developed to prepare thermoset epoxy polymer-layered silicate nanocomposites in which curing agents can be directly intercalated into the intragallery without the need for alkylammonium ions on the exchange sites. This new development has resulted in a greater improvement in the overall properties of thermoset polymer-clay nanocomposites. The exfoliation chemistry was extended further to other thermoset silicone polymer systems. The new polysiloxane-layered silicic acid nanocomposites were prepared with promising mechanical properties. Some fundamental chemistry and physics issues regarding nanocomposite formation were elucidated by this research work, particularly with regard to the relationship of microstructure and interfacial factors to the mechanical properties of the nanocomposites.

Wang, Zhen

15

40 CFR 721.5310 - Neononanoic acid, ethenyl ester.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Neononanoic acid, ethenyl ester. 721.5310 Section...Substances § 721.5310 Neononanoic acid, ethenyl ester. (a) Chemical substance...chemical substance identified as neononanoic acid, ethenyl ester (PMN...

2013-07-01

16

40 CFR 721.4215 - Hexanedioic acid, diethenyl ester.  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 false Hexanedioic acid, diethenyl ester. 721.4215 Section...Substances § 721.4215 Hexanedioic acid, diethenyl ester. (a) Chemical substance...chemical substance identified as hexanedioic acid, diethenyl ester (PMN...

2013-07-01

17

21 CFR 172.859 - Sucrose fatty acid esters.  

Code of Federal Regulations, 2010 CFR

... 3 2009-04-01 2009-04-01 false Sucrose fatty acid esters. 172.859 Section 172...CONSUMPTION Multipurpose Additives § 172.859 Sucrose fatty acid esters. Sucrose fatty acid esters identified in this...

2009-04-01

18

21 CFR 172.859 - Sucrose fatty acid esters.  

Code of Federal Regulations, 2010 CFR

... 3 2010-01-01 2009-04-01 true Sucrose fatty acid esters. 172.859 Section 172...CONSUMPTION Multipurpose Additives § 172.859 Sucrose fatty acid esters. Sucrose fatty acid esters identified in this...

2010-01-01

19

Wax Esters of Vegetable Oil Fatty Acids Useful as Lubricants.  

National Technical Information Service (NTIS)

Wax esters are prepared entirely from acids obtained from hydrogenated vegetable oils. Fatty alcohols, prepared by hydrogenolysis of the fatty acids, are esterified with the fatty acids to yield the wax esters. These esters have properties similar to thos...

E. W. Bell

1978-01-01

20

40 CFR 721.5310 - Neononanoic acid, ethenyl ester.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Neononanoic acid, ethenyl ester. 721.5310... § 721.5310 Neononanoic acid, ethenyl ester. (a...substance identified as neononanoic acid, ethenyl ester (PMN...Standard Test Method for Resistance of Protective Clothing...

2010-07-01

21

40 CFR 721.4215 - Hexanedioic acid, diethenyl ester.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Hexanedioic acid, diethenyl ester. 721... § 721.4215 Hexanedioic acid, diethenyl ester. (a...substance identified as hexanedioic acid, diethenyl ester (PMN...Standard Test Method for Resistance of Protective Clothing...

2009-07-01

22

Carboxylic Acid Esters as Substrates of Cholinesterases  

NASA Astrophysics Data System (ADS)

Data on the kinetics of the hydrolysis of various carboxylic acid esters by two main types of cholinesterases acetylcholinesterase from human erythrocytes and butyrylcholinesterase from horse blood serum are surveyed. It is shown that the rate of enzyme hydrolysis depends significantly on the structure of the acyl part of the ester molecule, the nature of the ester heteroatom, the structure of the alcohol component, and particularly the structure of the onium group. Esters based on natural products are of special interest as specific substrates of these enzymes. The role of the productive and non-productive sorption of the substrates in enzyme catalysis is demonstrated. The bibliography includes 81 references.

Brestkin, A. P.; Rozengart, E. V.; Abduvakhabov, A. A.; Sadykov, A. A.

1983-10-01

23

Conformations of Tartaric Acid and Its Esters,  

National Technical Information Service (NTIS)

Vibrational circular dichroism (VCD) spectra of optically active tartaric acid and its dimethyl, diethyl and diisopropyl esters were measured. It is found that VCD associated with the C -O stretching vibrations is identical in all species and reveals a co...

P. L. Polavarapu C. S. Ewig T. Chandramouly

1987-01-01

24

Flammability Studies of Polymer Layered Silicate Nanocomposites: Polyolefin, Epoxy and Vinyl Ester Resins  

NSDL National Science Digital Library

In the pursuit of improved approaches to fire retarding polymers a wide variety of concerns must be addressed, in addition to the flammability issues. For commodity polymers the low cost of these materials requires that the fire retardant (FR) approach also be of low cost. This limits solutions to the problem primarily to additive type approaches. These additives must be low cost and easily processed with the polymer. In addition, any additive must not excessively degrade the other performance properties of the polymer, and it must not create environmental problems in terms of recycling or disposal of the final product. Polymer layered silicate (PLS) nanocomposites are materials that may fulfil the above requirements for a high performance flame retardant. PLS nanocomposites are hybrid organic polymer-inorganic materials with unique properties when compared with conventional filled polymers [1]. For example, the mechanical properties of a nylon-6 layered-silicate nanocomposite, with a silicate mass fraction of only 5%, show excellent improvement over those for the pure nylon 6. The nanocomposite exhibits a 40% higher tensile strength, 68% greater tensile modulus, 60% higher flexural strength, and a 126% increased flexural modulus. The heat distortion temperature (HDT) is increased from 65 °C to 152 °C [2]. In some cases, increased thermal stability, an important property for improving flammability performance, as well as decreased gas permeability, and increased solvent resistance accompany the improved physical properties. We have reported on the flammability properties of delaminated nylon 6 layered silicate nanocomposites and intercalated polymer layered-silicate nanocomposites prepared from polystyrene (PS) and polypropylene-graft-maleic anhydride (PP-g-MA) [3, 4]. Here, we will briefly review these results and report on our initial studies of the flammability of thermoset PLS nanocomposites: intercalated vinyl ester silicate and intercalated epoxy silicate nanocomposites.

Gilman, J. W.; Kashiwagi, T.; Nyden, M. R.; Brown, J. E.; Jackson, C. L.; Lomakin, S.

1999-01-01

25

Phosphorus-based fatty acid methyl esters.  

PubMed

With the aim of designing novel transformable fatty acid diesters, various strategies for introducing phosphorus arms to the fatty backbone have been examined. While lithiated phosphine reacts classically to brominated fatty esters to afford the mono-addition product, the synthesis of phosphorylated diesters was found to be difficult, a fact related to the bulkiness of fatty acids and phosphine reagents. A base-induced dehydrochlorination reaction using ArPCl2 and hydroxy-terminated fatty esters resulted in metastable diester for which hydrolytic cleavage undergo phosphine oxidation and expulsion of one fatty chain. Alternatively, ArPOCl2 alleviates this drawback and provides stable, phosphorylated fatty acid diesters. PMID:23845998

Katir, Nadia; El Kadib, Abdelkrim; Castel, Annie

2013-07-08

26

Glycidyl Esters of Aromatic Acids  

Microsoft Academic Search

The reaction of substituted benzoic acids, dicarboxylic acids such as phthalic, terephthalic, and isophthalic acids, and the sodium or potassium salts of these acids with equimolar or excess epichlorohydrin in the presence of benzyltrimethylammonium chloride has been studied using various solvents such as toluene, dioxane, monochlorobenzene, and tetrachloroethylene. Use of the free carboxylic acids gave only fair to low yields

Yoshio Tanaka; Hiroshi Kakiuchi

1967-01-01

27

Lipid encapsulated docosahexaenoic acid methyl ester  

Technology Transfer Automated Retrieval System (TEKTRAN)

Encapsulation of structurally sensitive compounds within a solid lipid matrix provides a barrier to prooxidant compounds and effectively limits the extent of oxidative degradation. Encapsulated docosahexaenoic acid (DHA) methyl ester was examined as a model compound for functional foods and feeds. S...

28

Polyhydric alcohol esters of ?-sulfo fatty acids  

Microsoft Academic Search

Direct esterification of ?-sulfopalmitic and ?-sulfostearic acids with excess ethylene glycol, glycerol, pentaerythritol and\\u000a 2-methoxyethanol was carried out in carbon tetrachloride to give products containing essentially monoesters. Surface active\\u000a properties of these compounds were measured with emphasis on washing ability in combination with soap. The detergency of these\\u000a esters was compared with those of hexitol and sucrose ?-sulfo fatty acid

T. Micich; M. Sucharski; J. K. Weil; A. J. Stirton

1972-01-01

29

Synthesis of Mixed Esters of Ascorbic Acid Using Methyl Esters of Palm and Soybean Oils  

Microsoft Academic Search

Mixed esters of ascorbic acid were synthesized using methyl esters of palm and soybean oils as acyl donors, in acetone at 50C, and catalyzed by Novozym 435. A conversion of 62% was obtained with palm oil methyl ester at an ascorbic acid to acyl donor molar ratio of 1?4; the mixed ester contained 45.89% ascorbyl palmitate, 42.59% ascorbyl oleate and

R. Giridhar

2005-01-01

30

21 CFR 172.848 - Lactylic esters of fatty acids.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Lactylic esters of fatty acids. 172.848 Section 172.848 Food and Drugs...Additives § 172.848 Lactylic esters of fatty acids. Lactylic esters of fatty acids may be safely used in food in accordance...

2013-04-01

31

Insulinotropic Action of the Monoethyl Ester of Succinic Acid  

Microsoft Academic Search

1.Selected esters of succinic acid are currently under investigation as potential insulinotropic tools in the treatment of non-insulin-dependent diabetes. At variance with the methyl esters of succinic acid used in most of the work so far conducted from this perspective, the monoethyl ester of succinic acid (EMS) offers the advantage of avoiding the undesirable generation of methanol by intracellular hydrolysis.

Laurence Ladrire; Karim Louchami; Concepcin Viambres; Marcel M. Kadiata; Hassan Jijakli; Maria L. Villanueva-Peacarrillo; I. Valverde; Willy J. Malaisse

1998-01-01

32

40 CFR 721.10664 - Alkenedioic acid dialkyl ester, reaction products with alkenoic acid alkyl esters and diamine...  

Code of Federal Regulations, 2013 CFR

...New Uses for Specific Chemical Substances § 721...acid dialkyl ester, reaction products with alkenoic...generic). (a) Chemical substances and significant...reporting. (1) The chemical substances identified...acid dialkyl ester, reaction products with...

2013-07-01

33

Antioxidant potential of hydroxycinnamic acid glycoside esters.  

PubMed

Hydroxycinnamic acids are natural antioxidants found in fruits, vegetables, and cereals. In this study, the antioxidant activity of various types of hydroxycinnamoyl glycoside esters that mimic the structure of polymeric carbohydrates was studied in different model systems prone to oxidation, namely, liposomes and emulsions. In addition, radical scavenging activity against the stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical was tested. It was found that the esterification in the primary hydroxyl group of the glycoside resulted in the improved radical scavenging activity of both sinapoyl and feruloyl glycosides compared to conjugation to the secondary hydroxyl group. Increased activity was also observed, particularly in the case of feruloyl glucosides in inhibiting the oxidation of liposomes emulsions. The results showed that sinapic and ferulic acid glycoside esters were as effective or more efficient antioxidants than their free forms. In conclusion, the strength of their antioxidant effect depends on the nature of conjugation. PMID:18494493

Kylli, Petri; Nousiainen, Paula; Biely, Peter; Sipil, Jussi; Tenkanen, Maija; Heinonen, Marina

2008-05-22

34

Vesicles from sucrose fatty acid esters  

Microsoft Academic Search

It has been confirmed, from observations with an electron microscope after staining negatively with aqueous uranyl acetate\\u000a solutions and using a flourescent microscope, that sucrose fatty acid esters form closed vesicles. The range of particle size\\u000a of the vesicle, consisting of chromatographically fractionated sucrose dilaurate, was apparently 70700 nm in the longer diameter\\u000a of individual vesicles based on the transmission

Yutaka Ishigami; Hajime Machida

1989-01-01

35

Interaction of silicic acid with goethite.  

PubMed

The adsorption of Si on goethite (alpha-FeOOH) has been studied in batch experiments that cover the natural range of Si concentrations as found in the environment. The results have been interpreted and quantified with the charge distribution (CD) and multi-site surface complexation (MUSIC) model in combination with an extended Stern (ES) layer model option. This new double layer approach (ES) accounts for ordering of interfacial water molecules leading to stepwise changes in the location of electrolyte ions near the surface [T. Hiemstra, W.H. Van Riemsdijk, J. Colloid Interface Sci. 301 (2006) 1]. The Si adsorption on goethite peaks at a pH of approximately 9 and decreases at lower and higher pH values. Thermodynamically, the pH-dependency of silicic acid adsorption is related to the value of the proton co-adsorption and can also be linked to the Si charge distribution in the interface as is discussed. Based on published EXAFS data, the adsorption of Si on goethite was modeled as the formation of a bidentate surface complex. The ionic charge distribution (CD) of this complex can be calculated from the geometry of this surface complex, optimized with molecular orbital/density functional theory (MO/DFT), and combined with a correction for water dipole orientation. The resulting CD value has been applied successfully in the description of the adsorption data. The use of a theoretical CD value has the practical advantage of a reduction of the number of adjustable parameters with a factor 2. To describe the adsorption at a high Si loading, formation of a Si polymer, e.g. a tetramer, is proposed. Such a species is only contributing to the overall adsorption at solution concentrations above about 10(-4) M, where super saturation with respect to quartz exists. The adsorbed silica polymer hydrolyzes at high pH. The reactive ligand of the polymer is quite acid (logK approximately 6.5-7.1), which is typically for the triple bond SiO(-1) surface groups of polymerized Si, like amorphous SiO(2)(s), and the triple bond SiO(-1) ligand of the aqueous dimer Si(2)O(OH)(5)O(-1)(aq). The applied model correctly predicts the change of particles charge and the shift in IEP due to proton release upon Si adsorption. PMID:17306821

Hiemstra, Tjisse; Barnett, Mark O; van Riemsdijk, Willem H

2007-02-01

36

Affinity Labelling Enzymes with Esters of Aromatic Sulfonic Acids.  

National Technical Information Service (NTIS)

Novel esters of aromatic sulfonic acids are disclosed. The specific esters are nitrophenyl p- and m-amidino-phenylmethanesulfonate. Also disclosed is a method for specific inactivation of the enzyme, thrombin, employing nitrophenyl p-amidinophenylmethanes...

S. C. Wong E. Shaw

1977-01-01

37

40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Fatty acid polyamine condensate, phosphoric acid ester salts. 721.6200 Section 721.6200...Specific Chemical Substances § 721.6200 Fatty acid polyamine condensate, phosphoric acid ester...

2013-07-01

38

Vinylphosphonic acid-modified calcium aluminate and calcium silicate cements  

Microsoft Academic Search

Cementitious materials in terms of calcium phosphate cements (CPC) were prepared through the acid-base reaction between vinylphosphonic acid (VPA) and calcium aluminate cement (CAC) reactants or calcium silicate cement (CSC) reactants at 25 C. Using CAC, two factors were responsible for the development of strength in the cements: one is the formation of an amorphous calcium-complexed vinylphosphonate (CCVP) salt phase

T. Sugama; R. N. Mora

1996-01-01

39

76 FR 7703 - 1,4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4-Butanediol, Adipic Acid, and...  

Federal Register 2010, 2011, 2012, 2013

...4-Benzenedicarboxylic Acid, Dimethyl Ester, Polymer With 1,4- Butanediol, Adipic Acid...4-benzenedicarboxylic acid, dimethyl ester, polymer with 1,4-butanediol, adipic acid...4-benzenedicarboxylic acid, dimethyl ester, polymer with 1,4-butanediol, adipic...

2011-02-11

40

Activated sludge degradation of adipic acid esters.  

PubMed Central

The biodegradability of three aliphatic adipic acid diesters and a 1,3-butylene glycol adipic acid polyester was determined in acclimated, activated sludge systems. Rapid primary biodegradation from 67 to 99+% was observed at 3- and 13-mg/liter feed levels for di-n-hexyl adipate, di(2-ethylhexyl) adipate, and di(heptyl, nonyl) adipate in 24 h. When acclimated, activated sludge microorganisms were employed as the seed for two carbon dioxide evolution procedures, greater than 75% of the theoretical carbon dioxide was evolved for the three diesters and the polyester in a 35-day test period. The essentially complete biodegradation observed in these studies suggests that these esters would not persist when exposed to similar mixed microbial populations in the environment.

Saeger, V W; Kalley, R G; Hicks, O; Tucker, E S; Mieure, J P

1976-01-01

41

Use of fumaric acid esters in psoriasis.  

PubMed

Fumaric acid esters (FAE) are chemical compounds derived from the unsaturated dicarbonic acid fumaric acid. The usage of FAEs in treatment of psoriasis was introduced in the late 1950's. In the 1980s more standardized oral preparations of FAEs were developed containing dimethylfumarate (DMF) and salts of monoethylfumarate (MEF) as main compounds. In 1994, Fumaderm an enteric-coated tablet containing DMF and calcium, magnesium and zinc salts of MEF was approved for the treatment of psoriasis in Germany and since then has become the most commonly used systemic therapy in this country. Fumaric acids have been proven to be an effective therapy in patients with psoriasis even though the mechanisms of action are not completely understood. About 50-70% of the patients achieve PASI 75 improvement within four months of treatment and without any long-term toxicity, immunosuppressive effects or increased risk of infection or malignancy. Tolerance is limited by gastrointestinal side effects and flushing of the skin. This article reviews pharmacokinetics, uses, contraindications, dosages and side effects of treatment with FAEs. PMID:17456929

Roll, Antonie; Reich, Kristian; Boer, Almut

42

21 CFR 172.859 - Sucrose fatty acid esters.  

Code of Federal Regulations, 2013 CFR

...and tri-esters of sucrose with fatty acids and are derived from sucrose and edible tallow or hydrogenated edible tallow or edible vegetable oils. The only solvents which may be used in the preparation of sucrose fatty acid esters are...

2013-04-01

43

Preparation of {alpha},{beta}-unsaturated carboxylic acids and esters  

DOEpatents

Disclosed is a process for the preparation of {alpha},{beta}-unsaturated carboxylic acids and esters thereof which comprises contacting formaldehyde or a source of formaldehyde with a carboxylic acid, ester or anhydride in the presence of a catalyst comprising an oxide of niobium.

Gogate, M.R.; Spivey, J.J.; Zoeller, J.R.

1998-09-15

44

Adamantane dicarboxylic acid esters as possible additives to semisolid lubricants  

SciTech Connect

The high efficiency of adamantane carboxylic acid esters as antiwear additives to lubricating compounds based on polysiloxane liquids has been demonstrated. Dibutyl and dihexyl esters of 5,7-dimethyl-1,3-adainantane dicarboxylic acid, increasing by several factors the efficiency of a semisolid lubricant based on liquid methyldichlorophenylsiloxane, have been synthesized and characterized.

Novikova, I.A.; Dolgopolova, T.N.; Apryatkin, A.D. [A.V. Topchiyev Institute of Petrochemical Synthesis, Moscow (Russian Federation)] [and others

1993-12-31

45

Dissolution of silicates and the stability of polysilicic acid  

NASA Astrophysics Data System (ADS)

In several experiments albite, orthoclase, diopside, muscovite, sepiolite, magadiite, kenyaite, natrosilite, ?-Na 2Si 2O 5, sodium metasilicate, kanemite, quartz, opal, amorphous silica, and silica gel were dissolved in sulfuric aqueous solutions at pH 3. The experimental results show that most of the solutions contain silicic acid as both polymeric and monomeric species. Polysilicic acid is measured as high- and as low-molecular-weight silica. The polymers may amount to 50 mol.% of total dissolved silica. The proportion of polymers varies with reaction time of the dissolution experiment. As a function of time, polymers decompose into monomeric species, which is the stable silica species at experimental conditions. Therefore, the transfer of polysilicic acid into the solution represents a transition stage during the dissolution of silicates. The pH, the temperature, and the kind of the dissolved components of most natural waters provide high depolymerisation capacities. Polysilicic acid decomposes to monomer within a few hours or days in river and seawater. Therefore, it is not surprising that in most natural waters silicic acid consists of monomeric species. However, in natural environments with acid solutions rich in bivalent cations, polysilicic acid may exist as a metastable component over several months.

Dietzel, Martin

2000-10-01

46

40 CFR 721.3700 - Fatty acid, ester with styrenated phenol, ethylene oxide adduct.  

Code of Federal Regulations, 2013 CFR

...false Fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3700...3700 Fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a) Chemical...generically as fatty acid, ester with styrenated phenol, ethylene oxide adduct...

2013-07-01

47

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2010 CFR

...true Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2010-01-01

48

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2010 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2009-04-01

49

40 CFR 721.4250 - Hexanoic acid, 2-ethyl-, ethenyl ester.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Hexanoic acid, 2-ethyl-, ethenyl ester. 721...Chemical Substances § 721.4250 Hexanoic acid, 2-ethyl-, ethenyl ester. (a...chemical substance identified as hexanoic acid, 2-ethyl-, ethenyl ester...

2013-07-01

50

21 CFR 175.260 - Partial phosphoric acid esters of polyester resins.  

Code of Federal Regulations, 2011 CFR

...false Partial phosphoric acid esters of polyester resins. 175.260 Section 175.260...260 Partial phosphoric acid esters of polyester resins. Partial phosphoric acid esters of polyester resins identified in this section...

2013-04-01

51

40 CFR 721.3800 - Formaldehyde, condensated polyoxyethylene fatty acid, ester with styrenated phenol, ethylene...  

Code of Federal Regulations, 2010 CFR

...polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. 721.3800...polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct. (a) Chemical...polyoxyethylene fatty acid, ester with styrenated phenol, ethylene oxide adduct (PMN...

2010-07-01

52

21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Diacetyl tartaric acid esters of mono- and diglycerides...GRAS § 184.1101 Diacetyl tartaric acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and...

2009-04-01

53

21 CFR 184.1101 - Diacetyl tartaric acid esters of mono- and diglycerides.  

Code of Federal Regulations, 2010 CFR

...2009-04-01 true Diacetyl tartaric acid esters of mono- and diglycerides...GRAS § 184.1101 Diacetyl tartaric acid esters of mono- and diglycerides. (a) Diacetyl tartaric acid esters of mono- and...

2010-01-01

54

40 CFR 721.987 - Dialkylaminophenyl imino pyrazole acid ester (generic).  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Dialkylaminophenyl imino pyrazole acid ester (generic). 721.987...721.987 Dialkylaminophenyl imino pyrazole acid ester (generic). (a) Chemical...generically as dialkylaminophenyl imino pyrazole acid ester (PMN P-98-45) is...

2009-07-01

55

40 CFR 721.987 - Dialkylaminophenyl imino pyrazole acid ester (generic).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Dialkylaminophenyl imino pyrazole acid ester (generic). 721.987...721.987 Dialkylaminophenyl imino pyrazole acid ester (generic). (a) Chemical...generically as dialkylaminophenyl imino pyrazole acid ester (PMN P-98-45) is...

2013-07-01

56

40 CFR 721.987 - Dialkylaminophenyl imino pyrazole acid ester (generic).  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Dialkylaminophenyl imino pyrazole acid ester (generic). 721.987...721.987 Dialkylaminophenyl imino pyrazole acid ester (generic). (a) Chemical...generically as dialkylaminophenyl imino pyrazole acid ester (PMN P-98-45) is...

2010-07-01

57

40 CFR 721.10555 - Benzoic acid nonyl ester, branched and linear.  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Benzoic acid nonyl ester, branched and linear...Chemical Substances § 721.10555 Benzoic acid nonyl ester, branched and linear...chemical substance identified as benzoic acid nonyl ester, branched...

2013-07-01

58

40 CFR 721.10125 - Alkenedioic acid, dialkyl ester, reaction products with polyaminocarbomonocycle and alkenoic acid...  

Code of Federal Regulations, 2013 CFR

...New Uses for Specific Chemical Substances § 721...acid, dialkyl ester, reaction products with polyaminocarbomonocycle...generic). (a) Chemical substance and significant...reporting . (1) The chemical substances identified...acid, dialkyl ester, reaction products with...

2013-07-01

59

Process for the production of fatty acid alkyl esters  

US Patent & Trademark Office Database

A method for producing fatty acid alkyl esters from a feedstock, involving: (a) saponifying the feedstock with an alkali to form a saponified feedstock, (b) removing the water from the saponified feedstock to form a dried saponified feedstock containing no more than about 10% water, (c) esterifying the dried saponified feedstock with an alcohol in the presence of an inorganic acid catalyst to form fatty acid alkyl esters even with water present at levels up to about 3 wt %, and (d) recovering the fatty acid alkyl esters.

2002-06-04

60

Sugar fatty acid ester surfactants: Biodegradation pathways  

Microsoft Academic Search

In previous work, we found that the presence of a sulfonyl or alkyl group adjacent to the ester bond of sugar ester surfactants\\u000a is associated with a dramatic reduction in the rate of biodegradation relative to that of unsubstituted esters. In this study,\\u000a we investigated the pathways followed during the biodegradation of sucrose laurate, sucrose ?-sulfonyl laurate, and sucrose\\u000a ?-ethyl

Irene J. A. Baker; R. Ian Willing; D. Neil Furlong; Franz Grieser; Calum J. Drummond

2000-01-01

61

New synthesis of alkyl esters of ?-amino-acids  

Microsoft Academic Search

Summary 1.A new method is described for the preparation of ethyl esters of -aryl--aminoacids, depending on condensation of monoethyl malonate with aromatic aldehydes in the presence of alcoholic ammonia.2.The method serves for preparation of the ethyl esters of -phenyl--alanine, -(3-nitrophenyl)--alanine, and -amino--piperonylpropionic acid, and of monoethyl -amino--piperonylisocuccinate.3.The esters were converted into 4-aryldihydrouracils by boiling with urea solution.4.Ethyl esters were prepared

V. M. Rodionov; N. N. Bezinger

1952-01-01

62

A corollary to the silicic acid leakage hypothesis  

Microsoft Academic Search

The silicic acid leakage hypothesis (SALH) attempts to explain part of the large and regular atmospheric CO2 changes over the last glacial-interglacial cycles. It calls for a reduction in the carbonate pump through a growth in diatoms at the expense of coccolithophorids in low-latitude surface waters, driven by a leakage of high-Si:N waters from the Southern Ocean. Recent studies that

Katsumi Matsumoto; Jorge L. Sarmiento

2008-01-01

63

Mobilization of Arsenite by Competitive Interaction with Silicic Acid  

Microsoft Academic Search

Due to the acute toxicity of As, mobilization of even a small fraction of As into surface and ground waters used as a source for drinking water represents a substantial risk to human health. Here we evaluate the mobilization of arsenite (As(III)) from the Fe-(hydr)oxide min- eral goethite (a-FeOOH) through competitive displacement by silicic acid, a naturally occurring and ubiquitous

Todd P. Luxton; Christopher J. Tadanier; Matthew J. Eick

2006-01-01

64

Synthesis and Physical Properties of Estolide Ester Using Saturated Fatty Acid and Ricinoleic Acid  

PubMed Central

A study was conveyed to produce estolide ester using ricinoleic acid as the backbone. The ricinoleic acid reacted with saturated fatty acid from C8C18. These reactions were conducted under vacuum at 60C for 24?h without solvent. The reaction used acid catalyst, sulphuric acid. The new saturate ricinoleic estolide esters show superior low-temperature properties (?52 0.08C) and high flash point (>300C). The yield of the neat estolide esters ranged from 52% to 96%. The viscosity range was 51 0.08 to 86 0.01?cp. These new saturated estolide esters were also compared with saturated branched estolide esters.

Salimon, Jumat; Nallathamby, Neeranjini; Salih, Nadia; Abdullah, Bashar Mudhaffar

2011-01-01

65

Low molecular weight silicic acid inorganic compound complex as wood preservative  

Microsoft Academic Search

A new wood preservative containing low molecular weight and low-toxicity silicic acid (LWSA) was investigated. To prevent\\u000a environmental pollution with the wood preservative, a silicic acid monomer aqueous solution (SAMS) or colloidal silicic acid\\u000a solution (CSAS) was combined with various metal compounds or boric acid. Agents where SAMS or CSAS was combined with boric\\u000a acid gave good protection against decay

Haruhiko YAMAGUCHI

2002-01-01

66

Killing of intraerythrocytic Plasmodium falciparum by lysosomotropic amino acid esters  

Microsoft Academic Search

Esters of amino acids are known to penetrate into cells by simple diffusion. Subsequently, they are hydrolyzed by hydrolases to release the parent amino acid. Due to the abundance of hydrolases in phagolysosomes, amino acids accumulate, there because the rate of influx and hydrolysis exceed the rate of amino acid efflux through specific carriers. The osmotic effect of this accumulation

Miriam Krugliak; Jianmin Zhang; Edna Nissani; Sonia Steiner-Mordoch; Hagai Ginsburg

2003-01-01

67

21 CFR 172.852 - Glyceryl-lacto esters of fatty acids.  

Code of Federal Regulations, 2010 CFR

...of fatty acids. Glyceryl-lacto esters of fatty acids (the lactic acid esters of mono- and diglycerides) may be safely...conditions: (a) They are manufactured from glycerin, lactic acid, and fatty acids conforming with § 172.860...

2010-01-01

68

21 CFR 172.852 - Glyceryl-lacto esters of fatty acids.  

Code of Federal Regulations, 2010 CFR

...of fatty acids. Glyceryl-lacto esters of fatty acids (the lactic acid esters of mono- and diglycerides) may be safely...conditions: (a) They are manufactured from glycerin, lactic acid, and fatty acids conforming with § 172.860...

2009-04-01

69

Eicosapentaenoic acid geometrical isomer artifacts in heated fish oil esters  

Microsoft Academic Search

Gas liquid chromatography (GLC) on polar capillary columns showed that the ester of eicosapentaenoic acid (EPA) in distilled\\u000a fish oil methyl and ethyl esters sometimes is accompanied by several artifacts. The same EPA artifacts did not arise from\\u000a saponification and\\/or esterification but were formed in a significantly high yield during prolonged heating of the authentic\\u000a acid. Physicochemical studies, isolation and

R. C. Wijesundera; W. M. N. Ratnayake; R. G. Ackman

1989-01-01

70

[Test and analysis of acrylic acid ester in industry pipelines].  

PubMed

A new quality and quantity analyzing method for waste gas from chemical industry, especially for acrylic acid ester using air-sampling combined with GC/MS and honeywell air purifier system was firstly advanced in this paper. According to the experiments, the maximum disposal capability of the honeywell air purifier system for acrylic acid ester gas was calculated as about 1 kg x h(-1) and the feasibility and validity of the method was also proved by parallel tests. PMID:22468533

Wu, Bin; Zhang, Hong-Yan; Lu, Lin-Guang

2011-12-01

71

21 CFR 172.852 - Glyceryl-lacto esters of fatty acids.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Glyceryl-lacto esters of fatty acids. 172.852 Section 172.852 Food and...172.852 Glyceryl-lacto esters of fatty acids. Glyceryl-lacto esters of fatty acids (the lactic acid esters of mono- and...

2013-04-01

72

Potential for Biodegradation of Phthalic Acid Esters in Marine Regions  

PubMed Central

Di-(2-ethylhexyl) phthalate was the major phthalic acid ester in the Mississippi River estuary, with mean levels of 0.1 ?g/g (dry weight) in surface sediments, 1.0 ?g/liter in river water, and 0.7 ?g/liter in delta water. Bacteria that grew aerobically on dibutyl phthalate and o-phthalic acid were readily detected in the sediments and water. Pure cultures of bacteria were isolated on seven different phthalic acid esters from freshwater and marine sources. The marine isolates were taxonomically diverse and grew on a variety of phthalic acid esters. Dibutyl phthalate and o-phthalic acid supported growth in full-strength synthetic sea-water medium, but Na+ -dependent catabolism was demonstrable only for o-phthalic acid.

Taylor, Barrie F.; Curry, Richard W.; Corcoran, Eugene F.

1981-01-01

73

Polysilicic Acid Esters as Precursors to New Ceramic Materials.  

National Technical Information Service (NTIS)

Two simple siloxane ester chains, (Si(sub 2)O)(OCH(sub 3))(sub 6) and (Si(sub 3)O(sub 2))(OCH(sub 3))(sub 8), and a polysilicic acid ester (Si(sub 8)O(sub 12))(OCH(sub 3))(sub 8) were prepared. (sup 29)Si NMR and single-crystal x-ray analysis were used. H...

D. M. Millar

1987-01-01

74

21 CFR 178.3780 - Polyhydric alcohol esters of long chain monobasic acids.  

Code of Federal Regulations, 2010 CFR

...3780 Polyhydric alcohol esters of long chain...acids. Polyhydric alcohol esters of long chain...the fabrication of polyvinyl chloride and/or polyvinyl chloride copolymer...section, polyhydric alcohol esters of long...

2009-04-01

75

21 CFR 178.3780 - Polyhydric alcohol esters of long chain monobasic acids.  

Code of Federal Regulations, 2013 CFR

...3780 Polyhydric alcohol esters of long chain...acids. Polyhydric alcohol esters of long chain...the fabrication of polyvinyl chloride and/or polyvinyl chloride copolymer...section, polyhydric alcohol esters of long...

2013-04-01

76

40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...  

Code of Federal Regulations, 2010 CFR

...Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection...POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory §...

2009-07-01

77

40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...  

Code of Federal Regulations, 2010 CFR

...Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection...POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory §...

2010-07-01

78

40 CFR 417.140 - Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids...  

Code of Federal Regulations, 2012 CFR

...Applicability; description of the neutralization of sulfuric acid esters and sulfonic acids subcategory. 417.140 Section 417.140 Protection...POINT SOURCE CATEGORY Neutralization of Sulfuric Acid Esters and Sulfonic Acids Subcategory §...

2012-07-01

79

Fragrance material review on carbonic acid, methyl phenylmethyl ester.  

PubMed

A toxicologic and dermatologic review of carbonic acid, methyl phenylmethyl ester when used as a fragrance ingredient is presented. Carbonic acid, methyl phenylmethyl ester is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid (a chain of 1-4 carbons) to generate formate, acetate, propionate, butyrate, isobutyrate and carbonate esters. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for carbonic acid, methyl phenylmethyl ester were evaluated, then summarized, and includes: physical properties, acute toxicity, skin irritation, and skin sensitization data. A safety assessment of the entire AAASAE will be published simultaneously with this document. Please refer to Belsito et al. (2012) for an overall assessment of the safe use of this material and all AAASAE in fragrances. PMID:22414647

McGinty, D; Letizia, C S; Api, A M

2012-03-04

80

Chemo-enzymatic synthesis of disaccharide fatty acid esters  

Microsoft Academic Search

A novel enzymatic method for the synthesis of disaccharide fatty acid esters was developed with immobilizedMucor miehei lipase (Lipozyme IM-60; Novo Nordisk, Bagsvaerd, Denmark) as a catalyst. A range of lactose and maltose monoesters was prepared\\u000a in overall yields of 4877% from the corresponding sugar acetals and fatty acids.

Douglas B. Sarney; Herwig Kapeller; Guiseppe Fregapane; Evgeny N. Vulfson

1994-01-01

81

Increased Endobiotic Fatty Acid Methyl Esters Following Exposure to Methanol  

Microsoft Academic Search

Increased Endobiotic Fatty Acid Methyl Esters Following Exposure to Methanol. Kaphalia, B. S., Carr J. B., and Ansari, G. A. S. (1995). Fundam. Appl. Toxicol. 28. 264-273.Human exposure to methanol is likely to increase in the future due to its proposed use as an alternate automobile fuel. Since alcohols are known to esterify the fatty acids in the body and

Bhupendra S. Kaphalia; James B. Carr; G. A. S. Ansari

1995-01-01

82

Glycerin fatty acid esters as a new lubricant of tablets.  

PubMed

Lubrication properties were compared among glycerin fatty acid esters (Poem TR-FB and Poem TR-HB), magnesium stearate (Mg-St), and a sucrose fatty acid ester (RYOTO SUGAR ESTER S-370F: SSE). Granules containing 50% acetaminophen were prepared, and improvements in their fluidity by the lubricants were compared. The lubricant effects of TR-FB and HB during tablet punching (pressure transmission ratio, ejection force) were similar to those of Mg-St and were better than those of SSE. When the lubricant content, mixing time, and tabletting pressure were changed, TR-FB and TR-HB provided better tablet hardness than Mg-St. TR-FB and TR-HB made tablets more disintegratable than Mg-St. When the effects of these lubricants on the stability of acetylsalicylic acid (ASA) were compared, Mg-St promoted its hydrolysis, but TR-FB or TR-HB did not affect its stability. PMID:15778041

Aoshima, Hiroyuki; Miyagisnima, Atsuo; Nozawa, Yasuo; Sadzuka, Yasuyuki; Sonobe, Takashi

2005-04-11

83

Effects of specific fatty acid methyl esters on diesel fuel lubricity  

Microsoft Academic Search

Previous studies on the effects of vegetable oil methyl esters on diesel fuel lubricity have shown an increase in lubricity associated with the addition of these esters. This study sought to examine the effects of individual component fatty acid methyl esters (FAMEs) on diesel lubricity. Additive levels of 01.0% of specific fatty acid methyl esters were added to diesel fuel

Daniel P. Geller; John W. Goodrum

2004-01-01

84

Phthalic acid esters in dissolved fractions of landfill leachates  

Microsoft Academic Search

The distribution of phthalic acid esters (PAEs) (including diisobutylphthalate (DIBP), di-n-butylphthalate (DnBP) and bis(2-ethyl)hexylphthalate (DEHP)) in dissolved organic matter (DOM) fractions of leachates from sanitary or bioreactor landfills was evaluated. The leachate DOM was fractionated into humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) fractions. Measurements showed that the PAEs were bound mostly to the HA fraction in leachate,

Zhong Zheng; Pin-Jing He; Li-Ming Shao; Duu-Jong Lee

2007-01-01

85

The synthesis of fatty acid ethyl ester by carboxylester lipase.  

PubMed

Carboxylester lipase obtained from pig pancreas is associated with fatty acid ethyl ester synthase as judged by their elution in the same fraction from a heparin-Sepharose column, coprecipitations by antibody against purified carboxylester lipase and identical profiles of inhibition by diisopropyl fluorophosphate. Only one polypeptide of molecular mass 74-kDa in purified carboxylester lipase was labeled by immunostaining and affinity labeling with [3H]diisopropyl fluorosphate. Bovine serum albumin decreased the fatty-acid-ethyl-ester-synthesizing activity in a concentration-dependent manner. On incubation of purified carboxylester lipase with trioleylglycerol in an ethanol/water mixture, fatty acid ethyl ester was formed in the presence of a high concentration of bovine serum albumin. The acyltransfer activities from trioleylglycerol to ethanol (ethanolysis) were approximately 25-30 times higher than the acyltransfer activities to water (hydrolysis). When cholesterol was used as an acceptor, acyltransfer activity from trioleylglycerol to cholesterol (cholesterolysis) was also observed. We propose the following mechanism of fatty acid ethyl ester formation from triacyl glycerol. The enzyme attacks triacyl glycerol forming an acyl-enzyme intermediate, and during the deacylation process, alcohol binds to fatty acid as an acceptor. These results suggest that during lipid (triacyl glycerol) degradation, carboxylester lipase contributes to non-oxidative ethanol metabolism in the intestinal lumen. PMID:8076651

Tsujita, T; Okuda, H

1994-08-15

86

Fungicidal Activities of Dihydroferulic Acid Alkyl Ester Analogs  

Technology Transfer Automated Retrieval System (TEKTRAN)

The natural product dihydroferulic acid (DFA, 1) and the synthesized DFA methyl (4a), ethyl (4b), propyl (4c), hexyl (4d), octyl (4e), and decyl (4f) esters were examined for antifungal activity. Test fungi included Saccharomyces cerevisiae (wild type, and deletion mutants slt2' and bck1'), Aspergil...

87

Diffusion of phosphorous acid tributyl ester (1); air (2)  

NASA Astrophysics Data System (ADS)

This document is part of Subvolume A `Gases in Gases, Liquids and their Mixtures' of Volume 15 `Diffusion in Gases, Liquids and Electrolytes' of Landolt-Brnstein Group IV `Physical Chemistry'. It is part of the chapter of the chapter `Diffusion in Pure Gases' and contains data on diffusion of (1) phosphorous acid tributyl ester; (2) air

Winkelmann, J.

88

The factors of enzymatic selective synthesis carbohydrate fatty acid esters  

Microsoft Academic Search

Enzymes have been used to catalyze the reaction for the synthesis of carbohydrate fatty acid esters. The yields and selectivity of the reactions are influenced by many factors, especially, pretreatment of enzyme, solvents and substrates. In the pretreatment of enzyme, hydrophility of the support leads to an unfavored partition of water between enzyme and support, thus stripping essential water from

ZHANG Pei; Zhang Shu-fen; Yang Jin-zong

89

Analysis of Sucrose Fatty Acid Esters Composition by HPLC  

Microsoft Academic Search

Two procedures for quantitative analysis of sucrose fatty acid esters composition using HPLC are described. A reversed-phase column (RP-18) was used. The mobile phases consist of: a) methanol (95%) and isopropanol (5%); b) methanol and water (5%) using UV and RI detectors.

V. R. Kaufman; N. Garti

1981-01-01

90

Application of sucrose fatty acid esters in transdermal therapeutic systems  

Microsoft Academic Search

Transdermal therapeutic systems (TTSs) were studied applying different sucrose fatty acid esters (SEs) as drug delivery agents. Matrix and membrane controlled TTSs were prepared and compared. Membrane was made from a methacrylic polymer (Eudragit NE) of pH independent permeability which can achieve diffusion controlled drug liberation. Model drug was a water soluble ?-blocker, metoprolol, which has short biological half-life, so

G. Cska; S. Marton; R. Zelko; N. Otomo; I. Antal

2007-01-01

91

Dielectric properties of biodegradable polylactic acid and starch ester  

Microsoft Academic Search

In order to examine the applicability of biodegradable polymers to the fields of electrical insulation, several dielectric properties of two typical biodegradable polymers, polylactic acid (PLA) and starch ester (SE), are examined. A fairly larger amount of space charge is accumulated in both polymers in comparison to low-density polyethylene (LDPE). This seems partly due to the presence of hydroxyl and

N. Hirail; Y. Maeno; H. Tamura; D. Kaneko; T. Tanaka; Y. Ohki; Y. Tajitsu; M. Kohtoh; S. Okabe

2004-01-01

92

Inhibition of Dendritic Cell Differentiation by Fumaric Acid Esters  

Microsoft Academic Search

Fumaric acid esters have proved to be effective for the systemic treatment of severe psoriasis vulgaris. These compounds have been shown to induce a Th2-like cytokine secretion pattern in T cells and to reduce keratinocyte proliferation in vitro. Dendritic cells seem to be of major importance as regulatory cells driving the psoriatic tissue reaction. Monocytes or CD34-positive myeloid progenitor cells

Kejian Zhu; Ulrich Mrowietz

2001-01-01

93

In vitro pharmacokinetics of anti-psoriatic fumaric acid esters  

Microsoft Academic Search

BACKGROUND: Psoriasis is a chronic inflammatory skin disease that can be successfully treated with a mixture of fumaric acid esters (FAE) formulated as enteric-coated tablets for oral use. These tablets consist of dimethylfumarate (DMF) and salts of monoethylfumarate (MEF) and its main bioactive metabolite is monomethylfumarate (MMF). Little is known about the pharmacokinetics of these FAE. The aim of the

Nicolle HR Litjens; Elisabeth van Strijen; Co van Gulpen; Herman Mattie; Jaap T van Dissel; H Bing Thio; Peter H Nibbering

2004-01-01

94

Treatment of disseminated granuloma annulare with fumaric acid esters  

Microsoft Academic Search

BACKGROUND: Granuloma annulare is a granulomatous disease of unknown etiology. Various therapies have been tried in disseminated granuloma annulare (DGA), including corticosteroids, several variants of psoralen plus ultraviolet-A radiation, ultraviolet- A1 radiation, systemic retinoids, and dapsone, with variable success. We report a patient with recalcitrant DGA who was treated with fumaric acid esters (FAE). CASE PRESENTATION: A 40-year old Caucasian

Alexander Kreuter; Thilo Gambichler; Peter Altmeyer; Norbert H Brockmeyer

2002-01-01

95

The biosynthesis of benzoic acid glucosinolate esters in Arabidopsis thaliana  

Microsoft Academic Search

The siliques and seeds of Arabidopsis thaliana accumulate a series of glucosinolates containing an alkyl side chain of varying length with a terminal benzoate ester function. The biosynthesis of these unusual nitrogen- and sulfur-containing natural products was investigated by feeding isotopically-labeled precursors to detached flowering stems. Glucosinolates were extracted, purified and analyzed by tandem mass spectrometry. Phenylalanine and benzoic acid

Gerson Graser; Neil J. Oldham; Paul D. Brown; Ulrike Temp; Jonathan Gershenzon

2001-01-01

96

75 FR 4292 - 2-Propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl 2-methyl-2...  

Federal Register 2010, 2011, 2012, 2013

...2-Propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl...2-propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and 2-methylpropyl...2-propenoic acid, 2-ethylhexyl ester, polymer with ethenylbenzene and...

2010-01-27

97

40 CFR 721.990 - 1,4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized.  

Code of Federal Regulations, 2013 CFR

...4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized...4-Benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol, cyclized...4-benzedicarboxylic acid, dimethyl ester, polymer with 1,4 - butanediol,...

2013-07-01

98

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...  

Code of Federal Regulations, 2010 CFR

...with fatty acid esters and oils, and glyceride triesters. 721.9400 Section 721...with fatty acid esters and oils, and glyceride triesters. (a) Chemical substances...with fatty acid esters and oils, and glyceride triesters (PMNs...

2009-07-01

99

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...  

Code of Federal Regulations, 2010 CFR

...with fatty acid esters and oils, and glyceride triesters. 721.9400 Section 721...with fatty acid esters and oils, and glyceride triesters. (a) Chemical substances...with fatty acid esters and oils, and glyceride triesters (PMNs...

2010-07-01

100

40 CFR 721.9400 - Reaction product of phenolic pentaerythritol tetraesters with fatty acid esters and oils, and...  

Code of Federal Regulations, 2013 CFR

...with fatty acid esters and oils, and glyceride triesters. 721.9400 Section 721...with fatty acid esters and oils, and glyceride triesters. (a) Chemical substances...with fatty acid esters and oils, and glyceride triesters (PMNs...

2013-07-01

101

Physicochemical properties of ambiently dried sodium silicate based aerogels catalyzed with various acids  

Microsoft Academic Search

Experimental results on the physico-chemical properties of ambiently dried sodium silicate based aerogels catalyzed with various\\u000a acids are reported. The aerogels were prepared by hydrolysis and polycondensation of sodium silicate followed by subsequent\\u000a washings, surface chemical modification and ambient pressure drying using 10 various acid catalysts consisting of strong and\\u000a weak acids. The strength and concentration of acids have the

Uzma K. H. Bangi; A. Parvathy Rao; H. Hirashima; A. Venkateswara Rao

2009-01-01

102

Purification of Sucrose Esters of Fatty Acids by a Method of Ultrafiltration.  

National Technical Information Service (NTIS)

A sucrose ester product mixture containing glycerides and free fatty acids has been separated into a concentrated sucrose ester fraction and a concentrated glyceride-fatty acid fraction by ultrafilrtration through a polysulfone, anisotropic, microporous, ...

H. J. Zeringue R. O. Feuge

1978-01-01

103

40 CFR 721.10348 - Aspartic acid, N,N-(iminodi-alkanediyl)bis, tetraalkane esters (generic).  

Code of Federal Regulations, 2013 CFR

... 2013-07-01 2013-07-01 false Aspartic acid, N,Nâ²-(iminodi-alkanediyl)bis, tetraalkane esters...Specific Chemical Substances § 721.10348 Aspartic acid, N,N-(iminodi-alkanediyl)bis, tetraalkane esters...

2013-07-01

104

Use of Functionalized Mesoporous Silicates to Esterify Fatty Acids and Trasesterify Oils.  

National Technical Information Service (NTIS)

The present invention provides a method to prepare a fatty acid lower alkyl esters from a feedstock, such as a vegetable or an animal oil, comprising one or more fatty acid glycerol esters such as mono-, di- or tri-glycerides, and free fatty acids, compri...

D. R. Radu V. S. Yin Lin

2004-01-01

105

Identification of Formic Acid as the p-Bromophenacyl Ester  

Microsoft Academic Search

IN the course of work on the microbial metabolism of glycine and glyoxylic acid we have had occasion to isolate formic acid as the p-bromophenacyl ester which is widely quoted1,2 as having m.p. 140. It was observed that the derivative, m.p. 140-42, isolated from authentic sodium 14C-formate (95,200 counts\\/min.\\/mol.) was inactive and showed no depression in melting point when mixed

G. W. Crosbie

1962-01-01

106

Esters of propylene glycol phosphoric and propylene glycol thiophosphoric acids  

Microsoft Academic Search

Summary 1.A study was made of the action of phosphorus oxychloride and phosphoric thiotrichloride on propylene glycol in presence of hydrogen chloride-binding media. The chloride of propylene glycol phosphoric and propylene glycol thiophosphoric acids were synthesized.2.12 new mixed cyclic esters of phosphoric and thiophosphoric acids were synthesized by the action of propylene glycol phosphoryl and thiophosphoryl chlorides on sodium alkoxides

B. A. Arbuzov; K. V. Nikonorov; Z. G. Shishova

1954-01-01

107

Potential synthetic lubricants: Esters of C 18 -saturated cyclic acids  

Microsoft Academic Search

A series of 16 esters of C18-saturated cyclic acids (HCal) were prepared, and partial evaluation showed that several have qualities that recommend them\\u000a as potential low-temp lubricants. Starting materials used were primary, straight, and branched chain alcohols C4C7; perfluoro alcohols; phenol; cyclohexanol; and C18-saturated cyclic alcohols prepared from cyclic acids. Viscosities were measured at ?40, 100, and 210F. Their viscosity

J. P. Friedrich; E. W. Bell; L. E. Gast

1965-01-01

108

Kinetic resolution of tropic acid ethyl ester and its derivatives by lipase PS  

Microsoft Academic Search

The first kinetic resolution of tropic acid ethyl ester (TAEE) with lipase PS and vinyl acetate as an acylating agent is reported. The resulting (S)-(?)-3-acetoxy tropic acid ethyl ester and (R)-(+)-tropic acid ethyl ester are produced in high yields and in excellent ee (8794%). The method has been extended to resolve a variety of tropic acid ester derivatives. In addition,

Mary Rose Atuu; Syed J. Mahmood; Frank Laib; M. Mahmun Hossain

2004-01-01

109

Red blood cell fatty acid ethyl esters: a significant component of fatty acid ethyl esters in the blood  

Microsoft Academic Search

Although alcohol abuse is known to cause an ar- ray of ethanol-induced red blood cell (RBC) abnormalities, the underlying molecular mechanisms remain poorly under- stood. Fatty acid ethyl esters (FAEEs) are toxic, nonoxida- tive ethanol metabolites that have been found in blood, plasma, and tissues. Because FAEEs have been shown to be incorporated into phospholipid bilayers, we conducted a controlled

Catherine A. Best; Joanne E. Cluette-Brown; Miho Teruya; Ami Teruya; Michael Laposata

2003-01-01

110

Encapsulating fatty acid esters of bioactive compounds in starch  

NASA Astrophysics Data System (ADS)

Interest in the use of many bioactive compounds in foods is growing in large part because of the apparent health benefits of these molecules. However, many of these compounds can be easily degraded during processing, storage, or their passage through the gastrointestinal tract before reaching the target site. In addition, they can be bitter, acrid, or astringent, which may negatively affect the sensory properties of the product. Encapsulation of these molecules may increase their stability during processing, storage, and in the gastrointestinal tract, while providing controlled release properties. The ability of amylose to form inclusion complexes and spherulites while entrapping certain compounds has been suggested as a potential method for encapsulation of certain molecules. However, complex formation and spherulitic crystallization are greatly affected by the type of inclusion molecules, type of starch, and processing conditions. The objectives of the present investigation were to: (a) study the effect of amylose, amylopectin, and intermediate material on spherulite formation and its microstructure; (b) investigate the formation of amylose and high amylose starch inclusion complexes with ascorbyl palmitate, retinyl palmitate, and phytosterol esters; (c) evaluate the ability of spherulites to form in the presence of fatty acid esters and to entrap ascorbyl palmitate, retinyl palmitate, and phytosterol esters; and (d) evaluate the effect of processing conditions on spherulite formation and fatty acid ester entrapment. Higher ratios of linear to branched molecules resulted in the formation of more and rounder spherulites with higher heat stability. In addition to the presence of branches, it appears that spherulitic crystallization is also affected by other factors, such as degree of branching, chain length, and chain length distribution. Amylose and Hylon VII starch formed inclusion complexes with fatty acid esters of ascorbic acid, retinol, or phytosterols. However, only retinyl palmitate formed a complex with amylopectin. In general, ascorbyl palmitate resulted in the highest complexation, followed by retinyl palmitate and phytosterol ester. The presence of native lipids in Hylon VII starch did not inhibit complex formation. On the contrary, native lipids appear to increase the complexation yield and thermal stability of the starch-fatty acid ester inclusion complexes, possibly due to the formation of ternary complexes. From the three fatty acid esters studied, only ascorbyl palmitate was entrapped in starch spherulites. Various structures including round spherulites, various sizes of torus-shape spherulites, non-spherulitic birefringent and non-birefringent particles, "balloon" morphologies, and gel-like material were formed depending on processing conditions. However, only the torus-shape spherulites, and some non-spherulitic birefringent and non-birefringent particles showed ascorbyl palmitate entrapment. The % yield of the precipitate increased with higher % of added Hylon VII, and decreased with higher heating temperature and faster cooling rates. The amount of entrapped ascorbyl palmitate in the starch precipitate seems to be governed by the amount of this compound added during processing. This study showed that starch can form inclusion complexes with fatty acid esters which may be used for the delivery of certain bioactive molecules. In addition, encapsulation of fatty acid esters in starch spherulites may be a good potential delivery system for water soluble bioactive molecules. However, further research is necessary to gain a better understanding of the type of molecules that can be entrapped in starch spherulites, and the factors affecting spherulitic crystallization and bioactive compound entrapment.

Lay Ma, Ursula Vanesa

111

75 FR 52269 - Acetic Acid Ethenyl Ester, Polymer With Oxirane; Tolerance Exemption  

Federal Register 2010, 2011, 2012, 2013

...FRL-8841-2] Acetic Acid Ethenyl Ester, Polymer With Oxirane; Tolerance Exemption AGENCY...residues of acetic acid ethenyl ester, polymer with oxirane; when used as an inert ingredient...residues of acetic acid ethenyl ester, polymer with oxirane on food or feed...

2010-08-25

112

40 CFR 721.6110 - Alkyldi(alkyloxyhydroxypropyl) derivative, phosphoric acid esters, potassium salts.  

Code of Federal Regulations, 2013 CFR

...derivative, phosphoric acid esters, potassium salts. 721.6110 Section 721.6110 Protection...derivative, phosphoric acid esters, potassium salts. (a) Chemical substance and significant...derivative, phosphoric acid esters, potassium salts (PMN P-91-818) is subject to...

2013-07-01

113

21 CFR 573.640 - Methyl esters of higher fatty acids.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Methyl esters of higher fatty acids. 573.640 Section 573.640 Food...573.640 Methyl esters of higher fatty acids. The food additive methyl esters of higher fatty acids may be safely used in animal feeds in...

2013-04-01

114

40 CFR 721.10412 - Phosphonic acid ester (generic) (P-07-706).  

Code of Federal Regulations, 2013 CFR

...2013-07-01 2013-07-01 false Phosphonic acid ester (generic) (P-07-706). ...Substances § 721.10412 Phosphonic acid ester (generic) (P-07-706). ...substance identified generically as phosphonic acid ester (PMN P-07-706) is...

2013-07-01

115

40 CFR 721.9965 - Fatty acids, C10-13 - branched, vinyl esters.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Fatty acids, C10-13 - branched, vinyl esters. 721.9965 Section...721.9965 Fatty acids, C10- 13 - branched, vinyl esters. (a) Chemical substance...identified as fatty acids, C10-13 - branched, vinyl esters (PMN...

2009-07-01

116

Process for the generation of α,β-unsaturated carboxylic acids and esters using niobium catalyst  

Microsoft Academic Search

A process using a niobium catalyst includes the step of reacting an ester or carboxylic acid with oxygen and an alcohol in the presence a niobium catalyst to respectively produce an α,β-unsaturated ester or carboxylic acid. Methanol may be used as the alcohol, and the ester or carboxylic acid may be passed over the niobium catalyst in a vapor stream

M. R. Gogate; J. J. Spivey; J. R. Zoeller

1999-01-01

117

Process for the generation of .alpha., .beta.-unsaturated carboxylic acids and esters using niobium catalyst  

Microsoft Academic Search

A process using a niobium catalyst includes the step of reacting an ester or carboxylic acid with oxygen and an alcohol in the presence a niobium catalyst to respectively produce an .alpha.,.beta.-unsaturated ester or carboxylic acid. Methanol may be used as the alcohol, and the ester or carboxylic acid may be passed over the niobium catalyst in a vapor stream

Makarand Ratnakav Gogate; James Jerome Spivey; Joseph Robert Zoeller

1999-01-01

118

?,?-Unsaturated monoterpene acid glucose esters: Structural diversity, bioactivities and functional roles  

Microsoft Academic Search

The glycosylation of lipophilic small molecules produces many important plant secondary metabolites. The majority of these are O-glycosides with relatively fewer occurring as glucose esters of aromatic or aliphatic acids. In particular, monoterpene acid glucose esters have much lower structural diversity and distribution compared to monoterpene glycosides. Nevertheless, there have been over 20 monoterpene acid glucose esters described from trees

Jason Q. D. Goodger; Ian E. Woodrow

119

Nucleophilic Displacements on Phosphonic Acid Esters.  

National Technical Information Service (NTIS)

Data on the reaction of p-nitrophenyl methylphosphonate with a variety of hydroxamic acids is reported and discussed. Various experimental difficulties served to limit the number of successful trials. An attempt to obtain Bronsted plot for the observed da...

J. O. Edwards M. J. Biallas H. J. Brass R. A. DiPrete

1966-01-01

120

Testing the role of silicic acid and bioorganic materials in the formation of rock coatings  

NASA Astrophysics Data System (ADS)

Silica, amino acids, and DNA were recently discovered in desert varnish. In this work we experimentally test the proposed role of silicic acid and bio-chemicals in the formation of desert varnish and other rock coatings. We have developed a protocol in which the rocks were treated with a mixture of silicic acid, sugars, amino acids, metals and clays, under the influence of heat and UV light. This protocol reflects the proposed mechanism of the polymerization of silicic acid with the biooganic materials, and the laboratory model for the natural conditions under which the desert varnish is formed. Our experiments produced coatings with a hardness and morphology that resemble the natural ones. These results provide a support for the role of silicic acid in the formation of rock coatings. Since the hard silica-based coatings preserve organic compounds in them, they may serve as a biosignature for life, here or possibly on Mars.

Kolb, Vera M.; Philip, Ajish I.; Perry, Randall S.

2004-11-01

121

Testing the Role of Silicic Acid and Bioorganic Materials in the Formation of Rock Coatings  

SciTech Connect

Silica, amino acids, and DNA were recently discovered in desert varnish. In this work we experimentally test the proposed role of silicic acid and bio-chemicals in the formation of desert varnish and other rock coatings. We have developed a protocol in which hte rocks were treated with a mixture of silicic acid, sugars, amino acids, metals and clays, under the influence of heat and UV light. This protocol reflects the proposed mechanism of hte polymerization of silicic acid with the bioorganic materials, and the laboratory model for the natural conditions under which the desert varnish is formed. Our experiments produced coatings with a hardness and morphology that resemble the nature ones. These results provide a support for the role of silicic acid in the formation of rock coatings. Since the hard silica-based coatings preserve organic compounds in them, they may serve as a biosignature for life, here or possibly Mars.

Kolb, Vera; Philip, Ajish I.; Perry, Randall S.

2004-12-01

122

Kinetically controlled synthesis of monoglyceryl esters from chiral and prochiral acids methyl esters catalyzed by immobilized Rhizomucor miehei lipase  

Microsoft Academic Search

Partial acylation of only one primary hydroxyl group of glycerol generates a chiral center at position 2. Rhizomucor miehei lipase (RML) catalyzes the kinetically controlled transesterification of different aromatic carboxylic acids methyl esters with glycerol. High synthetic yields of glyceryl esters (around 7080%) were obtained even in the presence of significant concentrations of water (from 5% to 20%). After a

Andreina Acosta; Marco Filice; Gloria Fernandez-Lorente; Jose M. Palomo; Jose M. Guisan

2011-01-01

123

Hydrolysis of tocopheryl and retinyl esters by porcine carboxyl ester hydrolase is affected by their carboxylate moiety and bile acids  

Microsoft Academic Search

The objective of this study was to examine the in vitro hydrolysis of vitamin E esters (?-tocopheryl acetate, ?-tocopheryl succinate and ?-tocopheryl nicotinate) by pancreatic carboxyl ester hydrolase (CEH) at the concurrent presence of different bile acids at different concentrations. The assay was performed by measuring the amount of ?-tocopherol released by porcine pancreatic juice upon addition to different solutions

Charlotte Lauridsen; Mette S. Hedemann; Sren K. Jensen

2001-01-01

124

Recovery of short, medium, and long chain fatty acid methyl esters using wet halogenated hydrocarbons  

Microsoft Academic Search

and SummaryFatty acid methyl esters are prepared and analyzed by gas liquid chromatography using a simple procedure that does not involve\\u000a evaporation steps or drying of the final extract. The esters of fatty acids down to caproate (C6) are recovered quantitatively. The long chain fatty acid esters, including the polyunsaturated esters, are also recovered\\u000a quantitatively and are at least as

Joseph MacGee; Kenneth G. Allen

1977-01-01

125

Evidence of chemical bonding to hydroxyapatite by phosphoric acid esters  

Microsoft Academic Search

Phosphoric acid esters (PAEs) have been used as a self-etching primer for composite-to-enamel bonding in adhesive dentistry. However, the chemical mechanism of their interactions with hydroxyapatite (HA) is not clear. In the present study, HA particles were mixed with Resulcin AquaPrime (Merz Co.) priming agent that contains a mixture of PAEs, and dried. The primer, HA and the mixture of

Baiping Fu; Xuemei Sun; Weixin Qian; Yanqing Shen; Ranran Chen; Matthias Hannig

2005-01-01

126

Effect of phthalic acid esters on mouse testes.  

PubMed

Effects of three phthalic acid esters (PAEs) on mouse testes are described and discussed. Zinc concentrations in the testes of mice fed a diet containing 2% dibutyl (DBP), di-iso-butyl (DIBP) or di-2-ethylhexyl phthalate (DEHP) were less than those of control animals. Testosterone concentrations in the testes were decreased in DEHP-treated mice, and the relative testis weight of DBP-, DIBP- and DEHP-treated mice was increased. PMID:7394838

Oishi, S; Hiraga, K

1980-05-01

127

p-Coumaric acid esters from Tanacetum longifolium  

Microsoft Academic Search

Two new long chain alkyl p-coumaric acid esters (23) along with eicosanyl trans-p-coumarate (1) were isolated from chloroform extract of the roots of Tanacetum longifolium. The structures of new compounds were assigned as 21?-hydroxyheneicosanyl-4-hydroxy-(cis and trans) p-coumarate (2a, 2b) and 27?-hydroxy heptacosanyl-cis-p-coumarate (3) by extensive chromatographic and spectroscopic analysis and by comparison with literature data of known compounds.

Umar Mahmood; Vijay K. Kaul; Ruchi Acharya; Leopold Jirovetz

2003-01-01

128

p-coumaric acid esters from Tanacetum longifolium.  

PubMed

Two new long chain alkyl p-coumaric acid esters (2-3) along with eicosanyl trans-p-coumarate (1) were isolated from chloroform extract of the roots of Tanacetum longifolium. The structures of new compounds were assigned as 21'-hydroxyheneicosanyl-4-hydroxy-(cis and trans) p-coumarate (2a, 2b) and 27'-hydroxy heptacosanyl-cis-p-coumarate (3) by extensive chromatographic and spectroscopic analysis and by comparison with literature data of known compounds. PMID:14559280

Mahmood, Umar; Kaul, Vijay K; Acharya, Ruchi; Jirovetz, Leopold

2003-10-01

129

Enzyme Catalyzed Regioselective Synthesis of Sucrose Fatty Acid Ester Surfactants  

Microsoft Academic Search

A commercial subtilisin preparation was used in pyridine to catalyze the regioselective conversion of sucrose and fatty acid vinyl esters into the 1?-O-acyl sucrose derivatives. The 1?-O-laury sucrose, 1?-O-myristyl sucrose and 1?-O-stearyl sucrose were obtained as the major products of these reactions. The 1?,6-di-O-acyl sucrose derivatives were also obtained as minor products. The critical micellar concentration (CMC) of each of

Tulay Polat; Hlne G. Bazin; Robert J. Linhardt

1997-01-01

130

4-Dimenthylaminopyridine or Acid-Catalyzed Synthesis of Esters: A Comparison  

ERIC Educational Resources Information Center

|A set of highly atom-economic experiments was developed to highlight the differences between acid- and base-catalyzed ester syntheses and to introduce the principles of atom economy. The hydrochloric acid-catalyzed formation of an ester was compared with the 4-dimethylaminopyradine-catalyzed ester synthesis.|

van den Berg, Annemieke W. C.; Hanefeld, Ulf

2006-01-01

131

Purification of Sucrose Esters of Fatty Acids by a Method of Ultrafiltration.  

National Technical Information Service (NTIS)

A sucrose ester product mixture containing sucrose esters, glycerides and free fatty acids, all fatty acid groups having carbon chains of 2-22 carbon atoms, has been separated into a concentrated sucrose ester fraction and a concentrated glyceride-fatty a...

H. J. Zeringue R. O. Feuge

1979-01-01

132

A Simple and Mild Procedure for the Preparation of Bile Acid Methyl Esters  

Microsoft Academic Search

Bile acid ester are useful intermediates in reaction schemes yielding bile alcohols and other acid derivatives. Reported methods for the preparation of bi le acid methyl or ethyl esters consist of dissolving the bile acid in a large excess of absolute alcohol (ei ther methanol or ethanol) containing a catalytic amount of concentrated mineral acid (either hydrochloric or sul furic).

Roberto Ballini; Angelo Carott

1983-01-01

133

Characterization of carotenoid fatty acid esters from the peels of the persimmon Diospyros kaki.  

PubMed

Separation and structural determination of the chloroform-soluble components obtained from the peels of the persimmon (Diospyros kaki Thunb.) were performed. ?-Carotene, lycopene, ?-cryptoxanthin mono-myristic acid ester, zeaxanthin di-myristic acid ester, the latter two of which were accompanied by a small amount of palmitoleic acid in the fatty acid moiety, and oleanolic acid were identified. Among these components, the mono-fatty acid ester of ?-cryptoxanthin and the di-fatty acid ester of zeaxanthin were characterized for the first time. PMID:23727781

Hitaka, Yuki; Nakano, Ai; Tsukigawa, Kenji; Manabe, Hideyuki; Nakamura, Hideaki; Nakano, Daisuke; Kinjo, Junei; Nohara, Toshihiro; Maeda, Hiroshi

2013-01-01

134

Convulsant properties of L-glutamic acid di-tert butyl ester.  

PubMed

Glutamic acid di-tert butyl ester (GTBE) was found to have a pronounced convulsant effect in mice and rats, producing recurrent clonic convulsions combined with postural and respiratory disturbances in a dosage of 0.5 mmol/kg (148 mg/kg). Tert-butyl ester derivatives of aspartic acid and alanine, and glutamic acid gamma-benzyl ester did not produce seizures. Various other glutamate esters, such as glutamic acid diethyl ester and glutamic acid dimethyl ester, have previously been found to have anticonvulsant effects, and also do not induce seizures. It is suggested that glutamic acid di-tert butyl ester may have specific pharmacological properties which differ from those of other known convulsant drugs. PMID:2863766

Freed, W J; Ghoz, E H; Crump, S

135

Silicic acid leakage from the Southern Ocean: Opposing effects of nutrient uptake and oceanic circulation  

NASA Astrophysics Data System (ADS)

Studies invoking the silicic acid leakage hypothesis to explain events of high biogenic opal deposition at low latitudes did not consider variations in formation rate of Southern Ocean intermediate waters. Comparison of ? 30Si records from the Southern Ocean to records of biogenic opal accumulation from low-latitude upwelling systems indicates a strong negative correlation between the silicic acid content of Southern Ocean surface waters and opal deposition at low latitudes during the last 80 kyr BP. This implies that Si leakage was somehow rendered ineffective when the silicic acid content of Southern Ocean waters was high. Comparison of opal accumulation records with records of intermediate water formation rates suggests that lower rates of intermediate water formation offset the higher silicic acid content of these water masses during glacial periods. This indicates that physical processes that control intermediate water transport dominate over biological processes that set the silicic acid content of Antarctic surface waters in determining the magnitude of silicic acid leakage from the Southern Ocean.

Crosta, X.; Beucher, C.; Pahnke, K.; Brzezinski, M. A.

2007-07-01

136

Electrochemical oxidation of esters of ethane-1,1,2,2-tetracarboxylic acid in the presence of electron carrier catalysts  

Microsoft Academic Search

1.Electrochemical oxidation of esters of ethane-1,1,2,2-tetracarboxylic acid in the presence of hydrohalic acid salts in acetonitrile leads to esters of ethylenetetracarboxylic acid; in alcohols not only an oxidative dehydrogenation takes place, but also esters of 1-alkoxyethane-1,1,2,2-tetracarboxylic acid are formed.2.When the reaction is carried out in methanol, the yield of the ester of ethylenetetracarboxylic acid and the ester of 1-methoxyethane-1,1,2,2-tetracarboxylic acid

M. N. linson; S. K. Fedukovich; G. I. Nikishin

1988-01-01

137

Phenylethyl esters of fatty acids for the analytical resolution of petroselinate and oleate  

Microsoft Academic Search

2-Phenylethyl esters of fatty acids were prepared readily by esterification of free fatty acids or transesterification of\\u000a other lipids. Compared with methyl esters, phenylethyl esters greatly improve the resolution of oleate and petroselinate by\\u000a both gas and high-performance liquid chromatography, and the ultraviolet absorption of the phenylethyl esters facilitates\\u000a detection of the derivatives by high-performance liquid chromatography (HPLC) ultraviolet detectors.

Linsen Liu; E. G. Hammond

1995-01-01

138

Electron-impact ionization of benzoic acid, nicotinic acid and their n-butyl esters  

NASA Astrophysics Data System (ADS)

Electron-impact ionization mass spectra, the decay of metastable ions, ionization and appearance energies and bond energies, as dissociation energies, are reported for the title compounds. An ionization energy of 9.47 eV was obtained for benzoic acid, 9.43 eV for benzoic acid n-butyl ester, 9.61 eV for nicotinic acid and 9.97 eV for nicotinic acid n-butyl ester. Molecular ions of both butyl esters show two common main fragmentation pathways: the first process is a McLafferty rearrangement, characterized by the transfer of one H-atom from the aliphatic ester chain, which leads to the ions of either the organic acid or 1-butene. From their appearance energies and known thermodynamic data, gas-phase formation enthalpies () of the parent n-butyl esters are calculated. Values of for benzoic acid n-butyl ester and for nicotinic acid n-butyl ester were obtained. The second process is characterized by the transfer of two H-atoms from the ester chain leading to a protonated form of the corresponding organic acids and C4H7 radicals. Good evidence is provided for the formation of methylallyl radicals. Appearance energies are used to calculate a proton affinity (PA) for benzoic acid. The obtained value of PA = (8.73 0.3) eV, corresponding to a protonation of the carbonyl group, is in close corroboration with published data (PA = 8.51 eV). Activation energies for the intermediate H-transfers were found to be insignificant. This methodic gateway is applied to the system of nicotinic acid and its butyl ester. Adopting the formation of a methylallyl radical, the obtained proton affinity of nicotinic acid, PA = 8.58 eV, is very near to the published data of benzoic acid. An alternative fragmentation mechanism leading to a value of PA [approximate] 9.5 eV (typical for a protonation of the pyridine-nitrogen) is very unlikely. It is concluded that this transfer of two H-atoms from the ester chain is controlled by a charge switching between the carboxylic oxygen atoms which leads to a regiospecific protonation site, in this case to the protonated carbonyl group. This is conform with a B3LYP DFT calculation with a corresponding proton affinity of PA = 8.29 eV.

Opitz, Joachim

2007-08-01

139

Fluorophilicity of Alkyl and Polyfluoroalkyl 1 Nicotinic Acid Ester Prodrugs.  

PubMed

The fluorophilicity of a series of hydrocarbon and fluorocarbon-functionalized nicotinic acid esters (nicotinates) is measured from their partitioning behavior (log K(P)) in the biphasic solvent system of perfluoro(methylcyclohexane) (PFMC) and toluene. The chain length of the hydrocarbon or fluorocarbon alkyl group of the ester ranges from one to twelve carbon atoms. Knowledge of the fluorophilicity of these solutes is relevant to the design of these prodrugs for fluorocarbon-based drug delivery. The experimental log K(p) values range from -1.72 to -3.40 for the hydrocarbon nicotinates and -1.64 to 0.13 for the fluorinated nicotinates, where only the prodrug with the longest fluorinated chain (2,2,3,3,4,4,5,5,6,6,7,7,8,8,8-pentadecafluorooctyl nicotinic acid ester) partitions preferentially into the fluorinated phase (log K(p) = 0.13). Predictions of the partition coefficients using solubility parameters calculated from group contribution techniques or molecular dynamics simulation are in reasonable agreement for the perhydrocarbon nicotinates and short chained perfluorinated nicotinates (? 0.3%-39% deviation). Significant deviations from experimental partition coefficients (greater than 100%) are observed for the longest chain perfluoroalkyl nicotinates. PMID:20567608

Ojogun, Vivian; Knutson, Barbara L; Vyas, Sandhya; Lehmler, Hans-Joachim

2010-07-01

140

Metabolism of hydroxycinnamic acids and their tartaric acid esters by Brettanomyces and Pediococcus in red wines.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Caffeic, p-coumaric, and ferulic acids and their corresponding tartaric acid esters (caftaric, coutaric, and fertaric, respectively) are found in wines in varying concentrations. While Brettanomyces and Pediococcus can utilize the free acids, it is not known whether they can metabolize the correspon...

141

Antioxidative activity of phenolic acids on triacylglycerols and fatty acid methyl esters from olive oil  

Microsoft Academic Search

The autoxidation of kinetically pure triacylglycerols and methyl esters of olive oil (TGOO and MEOO) in the presence of four different concentrations of p-coumaric, ferulic and caffeic acids at 100 C was studied. It was established that effectiveness and strength of the phenolic acids were greater in MEOO than in TGOO. In both lipid substates the molecules of phenolic acids

Emma M. Marinova; Nedjalka Vl. Yanishlieva

1996-01-01

142

Laser-specific photochemistry and lithography of DNQ-4-sulfonic-acid-ester-based photoresists  

NASA Astrophysics Data System (ADS)

The photolysis of DNQ-4-sulfonic acid esters yields 3- indenecarboxylic acid-1-sulfonic ester (3-ICA-1-SE). 3-ICA-1- SE reacts to the corresponding sulfonic acid. The rate of the ester cleavage is fast at exposure and slow in the dark. The deep UV lamp or laser exposure using low intensity is most effective for acid generation, pH change and network formation (image reversal).

Bendig, Juergen; Helm, Siegrun; Uhl, A.; Bauch, Lothar

1997-07-01

143

Application of sucrose fatty acid esters in transdermal therapeutic systems.  

PubMed

Transdermal therapeutic systems (TTSs) were studied applying different sucrose fatty acid esters (SEs) as drug delivery agents. Matrix and membrane controlled TTSs were prepared and compared. Membrane was made from a methacrylic polymer (Eudragit NE) of pH independent permeability which can achieve diffusion controlled drug liberation. Model drug was a water soluble beta-blocker, metoprolol, which has short biological half-life, so applying it in a TTS, the duration of its action could be prolonged. Sucrose fatty acid esters of different fatty acid chain lengths and consequently different hydrophilic-lipophilic balance (HLB) values were studied considering their effect on the metoprolol release from TTSs. Different mathematical models were applied for the evaluation of the release process. The results of the in vitro studies indicated that SEs of shorter fatty acid chain length and higher HLB value increased the amount of released drug about 10 times. SEs could be promising agents in transdermal therapeutic systems to control the drug release and cutaneous absorption. PMID:16963242

Cska, G; Marton, S; Zelko, R; Otomo, N; Antal, I

2006-07-21

144

Sulfamic Acid as a Cost-Effective Catalyst for Synthesis of ? -acyloxyacrylate Esters as Candidate Monomers for Bio-Based Polymers by Acylation of Pyruvate Esters  

Microsoft Academic Search

Sulfamic acid was used as an efficient catalyst and green alternative for metal-containing acidic material to promote the acylation of pyruvate esters to produce ? -acyloxyacrylate esters which were candidate monomers for bio-based polymers. Polymers from these monomers were useful materials for bio-based plastics which showed high heat resistance and transparency. A series of ? -acyloxyacrylate esters were converted from

Zhenxin Zhang; Baochun Ma; Qianqian Zhu; Yong Ding; Changming Wang; Wenfeng Song

2012-01-01

145

Formic acid: A neurologically active, hydrolyzed metabolite of insecticidal formate esters  

Microsoft Academic Search

Formate esters have potential uses as insecticides in both grain fumigation and public health pest management. This research investigated the hydrolytic metabolism and neurological effects of formate ester compounds. Studies were conducted using Drosophila and houseflies as models for other dipteran pests of medical importance. Results indicated significant formic acid liberation from a broad range of formate esters, both in

Cheol Song; Michael E. Scharf

2008-01-01

146

21 CFR 178.3770 - Polyhydric alcohol esters of oxidatively refined (Gersthofen process) montan wax acids.  

Code of Federal Regulations, 2013 CFR

... § 178.3770 Polyhydric alcohol esters of oxidatively refined...montan wax acids. Polyhydric alcohol esters of oxidatively refined...conditions: (a) The polyhydric alcohol esters identified in this...food-contact articles prepared from polyvinyl chloride and/or from...

2013-04-01

147

Alternative fuel properties of tall oil fatty acid methyl esterdiesel fuel blends  

Microsoft Academic Search

In this experimental work, tall oil methyl esterdiesel fuel blends as alternative fuels for diesel engines were studied. Tall oil methyl ester was produced by reacting tall oil fatty acids with methyl alcohol under optimum conditions. The blends of tall oil methyl esterdiesel fuel were tested in a direct injection diesel engine at full load condition. The effects of the

Duran Alt?parmak; Ali Keskin; Atilla Koca; Metin Gr

2007-01-01

148

Properties of Goethites Prepared under Acidic and Basic Conditions in the Presence of Silicate  

Microsoft Academic Search

Goethite in natural environments usually grows in the presence of dissolved silicate. To study silicate-associated goethite with specific properties, goethite was synthesized in an Fe(III) system at RT under acidic (OH\\/Fe = 2; pH 1.61.8) and basic (OH\\/Fe = 4; pH 1213) conditions at Si concentrations between 10?5 and 1 M. The goethites were characterized by transmission (TEM) and scanning

Susan Glasauer; Josef Friedl; Udo Schwertmann

1999-01-01

149

[Comparative bioavailability of eicosapentaenoic acid and docasahexaenoic acid from triglycerides, free fatty acids and ethyl esters in volunteers].  

PubMed

Comparative Bioavailability of Eicosapentaenoic Acid and Docosahexaenoic Acid from Triglycerides, Free Fatty Acids and Ethyl Esters in Volunteers. The bioavailability of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) from triglycerides, free fatty acids and ethyl esters was investigated in 8 female volunteers in a randomized triple cross-over trial with baseline control. EPA/DHA was administered in capsules in form of triglycerides (1.68/0.72 g), free fatty acids (1.35/1.065 g) and ethyl esters (1.86/1.27 g). The resulting EPA/DHA plasma levels were determined and evaluated. The mean relative bioavailability of EPA/DHA compared to triglycerides was 186/136% from free fatty acids and 40/48% from ethyl esters. Maximal plasma levels were about 50% higher with free fatty acids and about 50% lower with ethyl esters as compared to triglycerides. The tolerability of the free fatty acids was much worse than that of triglycerides and ethyl esters. The main side effect was eructation. PMID:2144420

Beckermann, B; Beneke, M; Seitz, I

1990-06-01

150

High performance liquid chromatographic separation of sucrose fatty acid esters  

Microsoft Academic Search

The synthesis of sucrose fatty acid esters always results in complex mixtures. Two procedures for quantitative analysis of\\u000a sucrose monoesters, respectively sucrose diesters, by means of high performance liquid chromatography on reversed-phase columns,\\u000a are described. A mixture of methanol and water (85:15, v\\/v) was used for the separation of the monoesters, while methanol,\\u000a ethyl acetate and water (65:25:10, v\\/v\\/v) was

M. E. A. P. Jaspers; F. F. van Leeuwen; H. J. W. Nieuwenhuis; G. M. Vianen

1987-01-01

151

Resonant electron capture by some amino acids esters  

PubMed Central

Resonant electron capture by Gly, Ala and Phe esters have shown that the most efficient negative ion (NI) fragmentations are associated with the C-termini. A new mechanism for the negative ion-forming processes at energies lower than those associated with the ?*OO shape resonance involves coupling between dipole-bound and valence negative ion states of the same symmetry for amino acid conformers with high permanent dipoles. The interaction avoids crossing of the NI states and instead leads to formation of two adiabatic potential energy surfaces. Underivatized amino acids most effectively fragment from the bottom adiabatic surface via generation of [M-H]? carboxylate anions by hydrogen-atom tunneling through the barrier; fragmentation of the their esters with formation of analogues [M-X]? NIs occurs through the upper adiabatic state without penetration of the barrier in which the energy of the valence ?*OX resonance exceeds the bond dissociation energy of the neutral molecule. Low and high temperature resonant electron capture experiments point to the importance of conformational preferences of the amino acids for optimum dissociation of the parent NIs in the gas phase.

Vasil'ev, Yury V.; Figard, Benjamin J.; Barofsky, Douglas F.; Deinzer, Max L.

2009-01-01

152

Simultaneous Separation of Monoacylglycerols, Free Fatty Acids, and Fatty Acid Methyl and Ethyl Esters by Reversed?Phase HPLC  

Microsoft Academic Search

We have developed a reversed?phase C18 high performance liquid chromatography (HPLC) method to separate molecular species of monoacylglycerols (MAG), fatty acids, fatty acid methyl esters, and fatty acid ethyl esters, simultaneously. This system also separates the regioisomers, 2?acyl?sn?glycerol and 1?acyl?sn?glycerol, with 2?acyl?sn?glycerol eluting earlier than 1?acyl?sn?glycerol. The elution order of the fatty acid and esters was ricinoleate, linolenate, linoleate, palmitate,

Charlotta Turner; Thomas A. McKeon

2005-01-01

153

Estimation of Hydrolysis Rate Constants of Carboxylic Acid Ester and Phosphate Ester Compounds in Aqueous Systems from Molecular Structure by SPARC.  

National Technical Information Service (NTIS)

SPARC (SPARC Performs Automated Reasoning in Chemistry) chemical reactivity models were extended to calculate hydrolysis rate constants for carboxylic acid ester and phosphate ester compounds in aqueous non- aqueous and systems strictly from molecular str...

S. H. Hilal

2006-01-01

154

Melting Points and Viscosities of Fatty Acid Esters that are Potential Targets for Engineered Oilseed  

Microsoft Academic Search

Our previous isolation of branched-chain fatty acid (BCFA) methyl esters from lanolin was improved and scaled up. Also, oleate\\u000a esters of isopropanol, oleyl alcohol and normal alcohols of 112 carbons chain lengths were prepared. Esters were made by\\u000a interesterification with sodium alcoholates and by esterification with Candida antarctica lipase. It proved easier to obtain pure esters by the enzymatic synthesis.

Linxing Yao; Earl Hammond; Tong Wang

2008-01-01

155

Effect of molecular weights of fatty acid esters on cetane numbers as diesel fuels  

Microsoft Academic Search

Cetane numbers for various esters of the saturated fatty acids from C8 to C18 have been determined according to ASTM D-613.\\u000a For the methyl esters the cetane numbers were found to increase in a non-linear relationship with the chain length of the\\u000a fatty acid. Cetane numbers of esters in which the fatty acid is kept constant while the alcohol esterified

W. E. Klopfenstein

1985-01-01

156

Neutral Lipid Biosynthesis in Engineered Escherichia coli: Jojoba Oil-Like Wax Esters and Fatty Acid Butyl Esters  

PubMed Central

Wax esters are esters of long-chain fatty acids and long-chain fatty alcohols which are of considerable commercial importance and are produced on a scale of 3 million tons per year. The oil from the jojoba plant (Simmondsia chinensis) is the main biological source of wax esters. Although it has a multitude of potential applications, the use of jojoba oil is restricted, due to its high price. In this study, we describe the establishment of heterologous wax ester biosynthesis in a recombinant Escherichia coli strain by coexpression of a fatty alcohol-producing bifunctional acyl-coenzyme A reductase from the jojoba plant and a bacterial wax ester synthase from Acinetobacter baylyi strain ADP1, catalyzing the esterification of fatty alcohols and coenzyme A thioesters of fatty acids. In the presence of oleate, jojoba oil-like wax esters such as palmityl oleate, palmityl palmitoleate, and oleyl oleate were produced, amounting to up to ca. 1% of the cellular dry weight. In addition to wax esters, fatty acid butyl esters were unexpectedly observed in the presence of oleate. The latter could be attributed to solvent residues of 1-butanol present in the medium component, Bacto tryptone. Neutral lipids produced in recombinant E. coli were accumulated as intracytoplasmic inclusions, demonstrating that the formation and structural integrity of bacterial lipid bodies do not require specific structural proteins. This is the first report on substantial biosynthesis and accumulation of neutral lipids in E. coli, which might open new perspectives for the biotechnological production of cheap jojoba oil equivalents from inexpensive resources employing recombinant microorganisms.

Kalscheuer, Rainer; Stoveken, Tim; Luftmann, Heinrich; Malkus, Ursula; Reichelt, Rudolf; Steinbuchel, Alexander

2006-01-01

157

Presystemic metabolism and intestinal absorption of antipsoriatic fumaric acid esters.  

PubMed

Psoriasis is a chronic inflammatory skin disease. Its treatment is based on the inhibition of proliferation of epidermal cells and interference in the inflammatory process. A new systemic antipsoriasis drug, which consists of dimethylfumarate and ethylhydrogenfumarate in the form of their calcium, magnesium and zinc salts has been introduced in Europe with successful results. In the present study, a homologous series of mono- and diesters of fumaric acid has been studied with respect to the sites and kinetics of presystemic ester degradation using pancreas extract, intestinal perfusate, intestinal homogenate and liver S9 fraction. In addition, intestinal permeability has been determined using isolated intestinal mucosa as well as Caco-2 cell monolayers, in order to obtain estimates of the fraction of the dose absorbed for these compounds. Relationships between the physicochemical properties of the fumaric acid esters and their biological responses were investigated. The uncharged diester dimethylfumarate displayed a high presystemic metabolic lability in all metabolism models. It also showed the highest permeability in the Caco-2 cell model. However, in permeation experiments with intestinal mucosa in Ussing-type chambers, no undegraded DMF was found on the receiver side, indicating complete metabolism in the intestinal tissue. The intestinal permeability of the monoesters methyl hydrogen fumarate, ethyl hydrogen fumarate, n-propylhydrogen fumarate and n-pentyl hydrogen fumarate increased with an increase in their lipophilicity, however, their presystemic metabolism rates likewise increased with increasing ester chain length. It is concluded that for fumarates, an increase in intestinal permeability of the more lipophilic derivatives is counterbalanced by an increase in first-pass extraction. PMID:12973823

Werdenberg, D; Joshi, R; Wolffram, S; Merkle, H P; Langguth, P

2003-09-01

158

40 CFR 721.4250 - Hexanoic acid, 2-ethyl-, ethenyl ester.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 false Hexanoic acid, 2-ethyl-, ethenyl ester...Substances § 721.4250 Hexanoic acid, 2-ethyl-, ethenyl ester...substance identified as hexanoic acid, 2-ethyl-, ethenyl...Standard Test Method for Resistance of Protective Clothing...

2010-07-01

159

40 CFR 721.4250 - Hexanoic acid, 2-ethyl-, ethenyl ester.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 false Hexanoic acid, 2-ethyl-, ethenyl ester...Substances § 721.4250 Hexanoic acid, 2-ethyl-, ethenyl ester...substance identified as hexanoic acid, 2-ethyl-, ethenyl...Standard Test Method for Resistance of Protective Clothing...

2009-07-01

160

Half esters of dibasic acids as additives in water-based cutting fluids  

Microsoft Academic Search

Several half esters from long chain dibasic acids were prepared, and corrosion and lubricity tests for these products as water-based\\u000a cutting fluid additives were made. Triethanolamine salts of half esters of sebacic acid and dodecanedioic acid showed effective\\u000a rust-inhibiting and anti-wear properties for water-based cutting fluids.

S. Watanabe; T. Fujita; T. Yoneshima; H. Nakagawa

1985-01-01

161

The effect of dietary fatty acid composition on liver retinyl ester (vitamin A ester) composition in the rat.  

PubMed

The dependence of liver retinyl ester (vitamin A ester) composition on dietary fatty acid composition was studied in rats. Weanling male Sprague-Dawley rats were fed purified test diets containing 8% of one of 10 test triglycerides (either tributyrin, tricaproin, tricaprylin, tricaprin, trilaurin, trimyristin, tripalmitin, tristearin, triolein, trilinolein) or corn oil (a mixed triglyceride) for 23 d after an initial 1-wk stabilization period. Essential fatty acids were provided by safflower oil (8 g/kg diet). Total liver fatty acid composition showed the expected responses to dietary fatty acid intake; short-chain and medium-chain fatty acids were readily elongated to palmitate and stearate, and palmitate and stearate were readily desaturated. Consumption of oleate or linoleate (as their triglycerides) markedly enriched their concentrations in liver lipids. The proportions of palmitate were generally greater in liver retinyl esters than in total liver fatty acids, and the proportions of oleate were less. However, retinyl ester composition was significantly affected by dietary triglyceride, particularly by diets providing long-chain fatty acids. Total liver vitamin A levels were depressed in the group fed trilinolein. PMID:2703916

Furr, H C; Clifford, A J; Smith, L M; Olson, J A

1989-04-01

162

40 CFR 721.10440 - Diphosphoric acid, polymers with ethoxylated reduced Me esters of reduced polymd. oxidized...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Diphosphoric acid, polymers with ethoxylated reduced Me esters of... § 721.10440 Diphosphoric acid, polymers with ethoxylated reduced Me esters of...substance identified as diphosphoric acid, polymers with ethoxylated reduced Me...

2013-07-01

163

Dietary Phenolic Acids and Derivatives. Evaluation of the Antioxidant Activity of Sinapic Acid and Its Alkyl Esters.  

PubMed

The action of sinapic acid and its alkyl esters as potential antioxidants has been investigated. For this purpose, a series of sinapic acid ester derivatives was synthesized and their antioxidant activities were evaluated using distinctive analytical methods, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and FRAP UV-vis methods and differential scanning calorimetry. The electron-donating activity and lipophilicity of these phenolic compounds were also evaluated. From the overall results it was concluded that alkyl ester sinapates (linear alkyl esters) present almost the same antioxidant activity, albeit slightly lower, exhibited by the parent compound (sinapic acid). Furthermore, the addition of an alkyl ester side chain has a positive effect on the partition coefficient of sinapic acid, improving its utility as an antioxidant in a more lipophilic medium. The data on the antioxidant activity obtained by different analytical methods correlated well with each other and have revealed interesting antioxidant data of alkyl esters of sinapic acid. PMID:20949946

Gaspar, Alexandra; Martins, Marta; Silva, Paulo; Garrido, E Manuela; Garrido, Jorge; Firuzi, Omidreza; Miri, Ramin; Saso, Luciano; Borges, Fernanda

2010-10-15

164

Method for separating mono- and di-octylphenyl phosphoric acid esters  

DOEpatents

A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters.

Arnold, Jr., Wesley D. (Oak Ridge, TN)

1977-01-01

165

Intramolecular interactions in ortho-methoxyalkylphenylboronic acids and their catechol esters.  

PubMed

Catechol esters of ortho-methoxyalkylphenylboronic acids have been synthesized and characterized by (17)O NMR spectroscopy. The results were compared with the data for the parent acids. The influence of intramolecular and intermolecular hydrogen bonds on the properties of the boronic acids has been discussed. The (17)O NMR data for the boronic esters proved that there are no O?B interactions in the investigated compounds. This fact is connected with weak Lewis acidity of the parent acids and their low sugars' receptors activity. Crystal structure of ortho-methoxyphenylboronic acid catechol ester was determined. PMID:23978747

Adamczyk-Wo?niak, Agnieszka; Borys, Krzysztof M; Czerwi?ska, Karolina; Gierczyk, B?a?ej; Jakubczyk, Micha?; Madura, Izabela D; Sporzy?ski, Andrzej; Tomecka, Ewelina

2013-08-08

166

Derivatives of Some 2-Chloroethylphosphonic Acid Esters, with Plant Growth Regulating Activity  

Microsoft Academic Search

A method for the synthesis of esters of 2-(dimethylsulfonium)ethylphos-phonic acid and the results of some trials showing the plant growth regulating activity of these compounds are presented. For the synthesis of the mentioned compounds, dimethyl sulphide is reacted with 2-chloroethylphosphonic acid esters; these esters are obtained through the complex[1] of AlCl3, PCl3 and 1,2-dichloroethan (1). Using the optimum reaction conditions,

Gheorghe Ilia

1999-01-01

167

?-sulfonated fatty acid esters: II. Solution behavior of ?-sulfonated fatty acid polyethylene glycol esters  

Microsoft Academic Search

Sodium ?-sulfonated, fatty acid polyethylene glycol monoesters [C\\u000a m\\u000a H2m+1CH(SO3Na)COO(C2H4O)\\u000a n\\u000a H] and diesters [C\\u000a m\\u000a H2m+1CH(SO3Na)COO(C2H4O)\\u000a n\\u000a COCH(SO3Na)C\\u000a m\\u000a H2m+1], wherem=1016 andn=135, were prepared by esterification of ?-sulfonated, fatty acids with polyethylene glycols, followed by neutralization\\u000a with NaOH. Crude products were purified by reversed-phase column chromatography on an octadecyl-modified silica gel. Characteristic\\u000a solution behavior of these ?-sulfonated fatty acid

Tomomichi Okano; Naoyuki Egawa; Masami Fujiwara; Masahiro Fukuda

1996-01-01

168

A Study of the AluminaSilica Gel Adsorbent for the Removal of Silicic Acid from Geothermal Water: Increase in Adsorption Capacity of the Adsorbent due to Formation of Amorphous Aluminosilicate by Adsorption of Silicic Acid  

Microsoft Academic Search

Two kinds of adsorbents (Si adsorbent and Al adsorbent) for the removal of silicic acid from geothermal water to retard the formation of silica scales were prepared using silicic acid contained in geothermal water. The Si adsorbent was prepared by evaporating geothermal water, and the Al adsorbent was prepared by evaporating geothermal water after the addition of aluminum chloride. The

Takushi Yokoyama; Akira Ueda; Koichi Kato; Katsumi Mogi; Shorin Matsuo

2002-01-01

169

Depigmenting effect of Kojic acid esters in hyperpigmented B16F1 melanoma cells.  

PubMed

The depigmenting effect of kojic acid esters synthesized by the esterification of kojic acid using Rhizomucor miehei immobilized lipase was investigated in B16F1 melanoma cells. The depigmenting effect of kojic acid and kojic acid esters was evaluated by the inhibitory effect of melanin formation and tyrosinase activity on alpha-stimulating hormone- (?-MSH-) induced melanin synthesis in B16F1 melanoma cells. The cellular tyrosinase inhibitory effect of kojic acid monooleate, kojic acid monolaurate, and kojic acid monopalmitate was found similar to kojic acid at nontoxic doses ranging from 1.95 to 62.5 ?g/mL. However, kojic acid monopalmitate gave slightly higher inhibition to melanin formation compared to other inhibitors at doses ranging from 15.63 to 62.5??g/mL. Kojic acid and kojic acid esters also show antioxidant activity that will enhance the depigmenting effect. The cytotoxicity of kojic acid esters in B16F1 melanoma cells was significantly lower than kojic acid at high doses, ranging from 125 and 500 ?g/mL. Since kojic acid esters have lower cytotoxic effect than kojic acid, it is suggested that kojic acid esters can be used as alternatives for a safe skin whitening agent and potential depigmenting agents to treat hyperpigmentation. PMID:23091364

Lajis, Ahmad Firdaus B; Hamid, Muhajir; Ariff, Arbakariya B

2012-10-02

170

Kinetically controlled synthesis of monoglyceryl esters from chiral and prochiral acids methyl esters catalyzed by immobilized Rhizomucor miehei lipase.  

PubMed

Partial acylation of only one primary hydroxyl group of glycerol generates a chiral center at position 2. Rhizomucor miehei lipase (RML) catalyzes the kinetically controlled transesterification of different aromatic carboxylic acids methyl esters with glycerol. High synthetic yields of glyceryl esters (around 70-80%) were obtained even in the presence of significant concentrations of water (from 5% to 20%). After a long incubation of the reaction mixture in the presence of the biocatalyst only pure free acid was obtained. Other lipases (from Geobacillus thermocatenulatus and from Thermomyces lanuginose) also catalyzed similar kinetically controlled transesterifications although less efficiently. RML immobilized on Sepharose-Q showed a high activity and specificity, compared to the immobilization by other techniques, only producing monoglyceryl esters with all substrates. In particular, monoglyceryl-phenylmalonate product was synthesized in 82% overall yield and >99% diastereomeric excess at pH 7.0 and 37C and 90% glycerol. PMID:20855204

Acosta, Andreina; Filice, Marco; Fernandez-Lorente, Gloria; Palomo, Jose M; Guisan, Jose M

2010-08-31

171

Enzymatic synthesis of a galactopyranose sophorolipid fatty acid-ester  

Microsoft Academic Search

Sophorolipid lactones produced by Candida bombicola were deacetylated and ring opened with sodium methoxide to their corresponding methyl esters. The methyl esters, after re-acetylation with vinyl acetate using an immobilized lipase, were transesterified with 1,2-3,4-di-O-isopropylidene-d-galactopyranose in tetrahydrofuran using the same lipase catalyst. The di-O-isopropylidene sophorolipid sugar esters were hydrolyzed to give the galactopyranose sophorolipid esters as the final products.

Alberto Nuez; Thomas A. Foglia; Richard Ashby

2003-01-01

172

The Solubility of C60 Fullerene in Long Chain Fatty Acids Esters  

Microsoft Academic Search

A series of fatty acid esters of glycerol as linseed, sunflower, soybean and olive oils have been tested as C60 fullerene solvents together with a mixture of methyl ester fatty acids derived from brassica oilseeds and used as a biofuel known as biodiesel. All the oils evaluated are effective solvents of C60. The solubility of C60 in the selected vegetable

Franco Cataldo; Tibor Braun

2007-01-01

173

Synthesis and study of properties of bis(allyloxymethyl)phosphonic acid and its esters  

Microsoft Academic Search

Conclusions 1.A method of preparation of bis(allyloxymethyl)phosphonic acid and its esters was developed.2.The ethyl ester of bis(allyloxymethyl)phosphonic acid is a low-toxicity compound with expressed depressive effects on the central nervous system.

I. V. Berezovskaya; L. A. Eliseeva; E. V. Kuznetsov; . Kh. Mukhametzyanova; I. M. Shermergorn

1968-01-01

174

Triterpenoids, p-coumaric acid esters and flavonoids from Artemisia igniaria.  

PubMed

Twenty-eight components were detected from the extract of Artemisia igniaria, which included four triterpenoids, eight p-coumaric acid long chain alkyl esters, seven flavonoids and nine common plant constituents. Their structures were determined by spectroscopic methods. This is the first recorded instance of beta-glutinanol and cis-p-coumaric acid eicosanyl ester occurring in nature. PMID:11105585

Hu, J; Feng, X

2000-10-01

175

Consideration on the relationship between dielectric breakdown voltage and water content in fatty acid esters  

Microsoft Academic Search

Recently, fatty acid esters synthesized from the natural oil obtained from plants have attracted much attention as an insulating oil from the viewpoint of environmental problems, fluidity, and greater resistance to dielectric breakdown than conventional mineral oil. In the present study, to clarify the reason for the superior moisture tolerance of fatty acid esters, the inter- and intramolecular movements of

T. Suzuki; R. Oba; A. Kanetani; T. Kano; T. Tamura; M. Kato; S. Watanabe; Y. Kasahara; M. Iwahashi

2011-01-01

176

The influence of molecular structure of fatty acid monoalkyl esters on diesel combustion  

Microsoft Academic Search

The subject of this paper is a series of experiments conducted on a single-cylinder research engine investigating the influence of molecular structure on the combustion behaviour of fatty acid alcohol ester (biodiesel) molecules under diesel engine conditions. The fuels employed in these experiments comprised various samples of pure individual fatty acid alcohol ester molecules of different structure, as well as

Alessandro Schnborn; Nicos Ladommatos; John Williams; Robert Allan; John Rogerson

2009-01-01

177

Sucrose fatty acid sulphate esters as novel vaccine adjuvant.  

PubMed

In search for novel adjuvants for human and veterinary vaccines, we focus on synthetic carbohydrates because microbial carbohydrates function as important alarming signals to the immune system. Mono- and disaccharides were added chemically with various functional groups and adjuvant activity and reactogenicity were determined in parallel. In our test model, we used poor immunogens to identify the most effective adjuvants and non-rodent mammals to facilitate extrapolation to humans. Disaccharides added with both fatty acid and sulphate esters and immobilized on a vehicle exerted high adjuvanticity. Chemical structure and presentation of the compound were optimized for a maximal in vivo performance. The formulation selected for human therapeutic vaccines (designated as 'CoVaccine HT') consists of a sucrose fatty acid sulphate ester immobilized on the oil droplets of a submicron emulsion of squalane-in-water. Both humoral and cell-mediated responses were enhanced in a dosedependent fashion against a wide range of antigens, e.g. inactivated viruses, bacterial subunits, recombinant proteins, virus-like particles and peptide-protein conjugates. Remarkably high booster reactions indicated strong immunological memory established by the first contact between host and antigen in presence of the adjuvant. In comparison with existing adjuvants, CoVaccine HT revealed similar or even higher adjuvanticity than mineral oil emulsions (O/W, W/O or O/W) but significantly lower reactogenicity. We concluded that CoVaccine HT is a promising adjuvant as it combines the efficacy of strong adjuvants with the safety of mild ones, is effective towards various types of antigens in large non-rodent mammals and is a chemically defined, stable, aqueous formulation. PMID:16823938

Hilgers, Luuk A T; Blom, Anneke G

2006-04-12

178

Characteristics of Palm Fatty Acid Ester (PFAE), a New Vegetable Based Insulating Oil for Transformers  

NASA Astrophysics Data System (ADS)

We have developed new vegetable based insulating oil for transformers called PFAE (Palm Fatty Acid Ester). PFAE has 0.6 times less viscosity and 1.3 times higher dielectric constant compared to mineral oil. The oxidative stability, biodegradability and acute toxicity to fish of PFAE has also been determined to be superior to mineral oil. In this paper, in order to optimize the characteristics of fatty acid esters originating from palm oil, several kinds of fatty acid alkyl esters were first synthesized in the laboratory by the molecular design technique and the transesterification from fatty acid methyl esters and alkyl alcohols. Next the electro-chemical characteristics of the fatty acid alkyl esters as insulating oil were analyzed.

Suzuki, Takashi; Kanoh, Takaaki; Koide, Hidenobu; Hikosaka, Tomoyuki

179

21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...  

Code of Federal Regulations, 2010 CFR

...2009-04-01 false Diacetyl tartaric acid esters of mono- and diglycerides...Agents § 582.4101 Diacetyl tartaric acid esters of mono- and diglycerides... (a) Product. Diacetyl tartaric acid esters of mono- and...

2009-04-01

180

[Development of the determination methods of fatty acid esters of chloropropanediols in fat-rich foods].  

PubMed

Fatty acid esters of chloropropanediols are a kinds of newly emerged food contaminants, especially 3-monochloropropane-1,2-diol (3-MCPD) esters that have been detected in many foodstuffs such as infant formula and edible oils at relatively high levels. Based on the Tolerable Dose Intake (TDI) of 3-MCPD, the intake of 3-MCPD from 3-MCPD esters may cause the health risk to human beings. The researches for the analysis of 3-MCPD esters have been carried out in some institutes abroad, but there were only a few in China. This paper reviews the methods for the determination of 3-MCPD esters in fat-rich foods, including the extraction, hydrolysis, the derivatization of 3-MCPD esters, the total amount of 3-MCPD esters and the amounts of monoesters and diesters of 3-MCPD. PMID:23697171

Yan, Xiaobo; Wu, Shaoming; Li, Nan; L, Huadong; Fu, Wusheng

2013-02-01

181

Phthalic acid esters in dissolved fractions of landfill leachates.  

PubMed

The distribution of phthalic acid esters (PAEs) (including diisobutylphthalate (DIBP), di-n-butylphthalate (DnBP) and bis(2-ethyl)hexylphthalate (DEHP)) in dissolved organic matter (DOM) fractions of leachates from sanitary or bioreactor landfills was evaluated. The leachate DOM was fractionated into humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) fractions. Measurements showed that the PAEs were bound mostly to the HA fraction in leachate, regardless of their landfill age or the presence of leachate recirculation. The PAEs affinity for HA and FA differed considerably relative to the sorption coefficients reported for model compounds. Molecular weight of DOM correlated with PAEs partition in collected leachate samples fractions while aromaticity was a poor predictor. Based on the presence of phenolic, carboxyl or amide groups in DOM fractions, hydrogen bonding is likely to be involved in interactions between PAEs and leachate DOM. The peptide groups, particularly presented in HA fraction, might explain the strong affinity of PAEs for HA. The fluorescence excitation emission matrix contour plots showed that the HyI fractions shared certain similarities with humic substances in terms of molecular structure, which may be one reason why PAEs exhibited a clear sorption to the HyI fractions. PMID:17631939

Zheng, Zhong; He, Pin-Jing; Shao, Li-Ming; Lee, Duu-Jong

2007-06-21

182

Resolution of Carboxylic Acids Using Copper (I)-Promoted Removal of Propargylic Esters Under Neutral Conditions  

PubMed Central

A method for the optical resolution of carboxylic acids is described. Condensation of racemic carboxylic acids with chiral terminal propargyl alcohols gave separable diastereomeric esters. Chromatographic separation followed by heating the individual diastereomers in methanol with catalytic copper (I) halide regenerated the carboxylic acids in good yields and in enantiomeric ratios of ?94%. This method is particularly useful for the resolution of carboxylic acids that are incompatible with conventional ester hydrolysis.

Ghosh, Partha

2013-01-01

183

Resolution of carboxylic acids using copper(I)-promoted removal of propargylic esters under neutral conditions.  

PubMed

A method for the optical resolution of carboxylic acids is described. Condensation of racemic carboxylic acids with chiral terminal propargyl alcohols gave separable diastereomeric esters. Chromatographic separation followed by heating the individual diastereomers in methanol with catalytic copper(I) halide regenerated the carboxylic acids in good yields and in enantiomeric ratios of ?94%. This method is particularly useful for the resolution of carboxylic acids that are incompatible with conventional ester hydrolysis. PMID:21491889

Ghosh, Partha; Aub, Jeffrey

2011-04-14

184

76 FR 41135 - 2-Propenoic acid, 2-methyl-, phenylmethyl ester, polymer with 2-propenoic acid and sodium 2...  

Federal Register 2010, 2011, 2012, 2013

...2-methyl-, phenylmethyl ester, polymer with 2- propenoic acid and sodium 2-methyl-2...2-methyl-, phenylmethyl ester, polymer with 2-propenoic acid and sodium 2-methyl...initiated (also known here as: ``the Polymer''); when used as an inert...

2011-07-13

185

Degradable poly(ester amide)s based on l-tartaric acid  

Microsoft Academic Search

A series of poly(ester amide)s with ester\\/amide group ratios ranging from 199 to 14 were obtained using 1,6-hexanediamine, 1,6-hexanediol and 2,3-di-O-methoxy-l-tartaric and succinic acids as building blocks. The ester linkages were introduced in pairs using as comonomer the diacid resulting from the esterification of 1,6-hexanediol with 2 mol of succinic anhydride. Polycondensastion reactions were carried out in solution at room

A. Alla; A. Rodrguez-Galn; A. Martnez de llarduya; S. Muoz-Guerra

1997-01-01

186

Asymmetric synthesis of diverse glycolic acid scaffolds via dynamic kinetic resolution of ?-keto esters.  

PubMed

The dynamic kinetic resolution of ?-keto esters via asymmetric transfer hydrogenation has been developed as a technique for the highly stereoselective construction of structurally diverse ?-substituted-?-hydroxy carboxylic acid derivatives. Through the development of a privileged m-terphenylsulfonamide for (arene)RuCl(monosulfonamide) complexes with a high affinity for selective ?-keto ester reduction, excellent levels of chemo-, diastereo-, and enantiocontrol can be realized in the reduction of ?-aryl- and ?-chloro-?-keto esters. PMID:23186551

Steward, Kimberly M; Corbett, Michael T; Goodman, C Guy; Johnson, Jeffrey S

2012-11-27

187

40 CFR 721.10326 - 2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...  

Code of Federal Regulations, 2013 CFR

...2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...2-Propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl 2-propenoate...2-propenoic acid, 2-methyl-, methyl ester, polymer with butyl 2-propenoate, ethyl...

2013-07-01

188

40 CFR 721.3130 - Sulfuric acid, mono-C9-11-alkyl esters, sodium salts.  

Code of Federal Regulations, 2013 CFR

...acid, mono-C9-11-alkyl esters, sodium salts. 721.3130 Section 721.3130...acid, mono-C9-11 -alkyl esters, sodium salts. (a) Chemical substance and...acid, mono-C9-11 -alkyl esters, sodium salts (PMN P-01-149; CAS...

2013-07-01

189

Synthesis and Characterization of Fatty Acid Methyl Ester by In-Situ Transesterification in Capparis Deciduas Seed  

Microsoft Academic Search

FAME) Fatty acid methyl ester is made virgin or used vegetable oils (both edible and non-edible) and animal fats. Fatty acid methyl ester operates in compression ignition engines like petro-diesel. Fatty acid methyl ester can be blended in any ratio with petroleum diesel fuels. It can be stored just like the petroleum diesel fuel. Petrodiesel can be replaced by biodiesel

Raghunath D POKHARKAR; Prasad E FUNDE; Shripad S JOSHI; Shirish S PINGALE

190

Metabolism of hydroxycinnamic acids and esters by Brettanomyces in different red wines  

Technology Transfer Automated Retrieval System (TEKTRAN)

Depending on the cultivars and other factors, differing concentrations of hydroxycinnamic acids (caffeic, p-coumaric, and ferulic acids) and their corresponding tartaric acid esters (caftaric, coutaric, and fertaric acid, respectively) are found in red wines. Hydroxycinnamic acids are metabolized by...

191

Rice Hull Ash and Silicic Acid as Adsorbents for Concentration of Bacteriocins  

Microsoft Academic Search

A model procedure has been developed for the rapid extraction of five bacteriocins (nisin, pediocin RS2, leucocin BC2, lactocin GI3, and enterocin CS1) from concentrated freeze-dried crude culture supernatants by adsorption onto acid or alkaline rice hull ash (RHA) or silicic acid (SA). Bacteriocins were adsorbed onto RHA or SA by a pH-dependent method and desorbed by decreasing the pH

M. E. JANES; R. NANNAPANENI; A. PROCTOR; M. G. JOHNSON

1998-01-01

192

Synthesis of esters of androgens with unsaturated fatty acids for androgen requiring therapy.  

PubMed

Androgens' metabolism and activity are gaining a more and more important role in human physiology particularly referring to aging and to neurodegenerative diseases. Androgen treatment is often required for long-lasting disorders. In order to improve their duration and effects, androgens can be administered as esters of carboxylic acids. The novelty of our research is the use of esters of androgens with specific unsaturated fatty acids, in order to reduce possible side effects particularly related to chronic pathologies with altered lipid homeostasis such as X-linked adrenoleukodystrophy and cardiovascular disorders. Thus the esters of the main androgenic substances testosterone, dihydrotestosterone (DHT) and their metabolite 5?-androstan-3?,17?-diol were chemically obtained by coupling with different unsaturated fatty acids. To this aim, fatty acids with various degree of unsaturation and belonging to different series were selected. Specifically, oleic acid (18:1, n-9), linoleic acid (18:2, n-6), and the n-3 fatty acids, ?-linolenic acid (18:3), eicosapentaenoic acid (EPA, 20:5), and docosahexaenoic acid (DHA, 22:6) were used obtaining corresponding esters with acceptable yields and good degree of purity. All the synthesized compounds were tested for their cytotoxic activities in mouse NIH3T3 and human astrocyte cell lines. The esters demonstrated good tolerability and no in vitro cytotoxic effect in both cell cultures. After these promising preliminary results, the esters will be suitable for in vivo studies in order to ascertain their pharmacokinetic characteristics and their biological effects. PMID:23095310

Aiello, F; Garofalo, A; Aloisi, A M; Lamponi, S; Magnani, A; Petroni, A

2012-10-22

193

Effects of phthalic acid esters on the liver and thyroid.  

PubMed

The effects, over periods from 3 days to 9 months of administration, of diets containing di-2-ethylhexyl phthalate are very similar to those observed in rats administered diets containing hypolipidemic drugs such as clofibrate. Changes occur in a characteristic order commencing with alterations in the distribution of lipid within the liver, quickly followed by proliferation of hepatic peroxisomes and induction of the specialized P-450 isoenzyme(s) catalyzing omega oxidation of fatty acids. There follows a phase of mild liver damage indicated by induction of glucose-6-phosphatase activity and a loss of glycogen, eventually leading to the formation of enlarged lysosomes through autophagy and the accumulation of lipofuscin. Associated changes are found in the kidney and thyroid. The renal changes are limited to the proximal convoluted tubules and are generally similar to changes found in the liver. The effects on the thyroid are more marked. Although the levels of thyroxine in plasma fail to about half normal values, serum triiodothyronine remains close to normal values while the appearance of the thyroid varies, very marked hyperactivity being noted 7 days after commencement of treatment, this is less marked at 14 days, but even after 9 months treatment there is clear cut evidence for hyperactivity with colloid changes which indicate this has persisted for some time. Straight chain analogs of di-2-ethylhexyl phthalate, di-n-hexyl phthalate and di-n-oxtyl phthalate differ entirely in their short-term effects on the liver and kidney but have similar effects on the thyroid. The short-term in vivo hepatic effects of the three phthalate esters can be reproduced in hepatocytes in tissue culture. All three phthalate esters, as well as clofibrate, have early marked effects on the metabolism of fatty acids in isolated hepatocytes. The nature of these changes is such as to increase storage of lipid in the liver. A hypothesis is presented to explain the progress from these initial metabolic effects to the final formation of liver tumors. PMID:3830106

Hinton, R H; Mitchell, F E; Mann, A; Chescoe, D; Price, S C; Nunn, A; Grasso, P; Bridges, J W

1986-12-01

194

Effects of phthalic acid esters on the liver and thyroid.  

PubMed Central

The effects, over periods from 3 days to 9 months of administration, of diets containing di-2-ethylhexyl phthalate are very similar to those observed in rats administered diets containing hypolipidemic drugs such as clofibrate. Changes occur in a characteristic order commencing with alterations in the distribution of lipid within the liver, quickly followed by proliferation of hepatic peroxisomes and induction of the specialized P-450 isoenzyme(s) catalyzing omega oxidation of fatty acids. There follows a phase of mild liver damage indicated by induction of glucose-6-phosphatase activity and a loss of glycogen, eventually leading to the formation of enlarged lysosomes through autophagy and the accumulation of lipofuscin. Associated changes are found in the kidney and thyroid. The renal changes are limited to the proximal convoluted tubules and are generally similar to changes found in the liver. The effects on the thyroid are more marked. Although the levels of thyroxine in plasma fail to about half normal values, serum triiodothyronine remains close to normal values while the appearance of the thyroid varies, very marked hyperactivity being noted 7 days after commencement of treatment, this is less marked at 14 days, but even after 9 months treatment there is clear cut evidence for hyperactivity with colloid changes which indicate this has persisted for some time. Straight chain analogs of di-2-ethylhexyl phthalate, di-n-hexyl phthalate and di-n-oxtyl phthalate differ entirely in their short-term effects on the liver and kidney but have similar effects on the thyroid. The short-term in vivo hepatic effects of the three phthalate esters can be reproduced in hepatocytes in tissue culture. All three phthalate esters, as well as clofibrate, have early marked effects on the metabolism of fatty acids in isolated hepatocytes. The nature of these changes is such as to increase storage of lipid in the liver. A hypothesis is presented to explain the progress from these initial metabolic effects to the final formation of liver tumors. Images FIGURE 2. a FIGURE 2. b FIGURE 3a. FIGURE 3b. FIGURE 3c.

Hinton, R H; Mitchell, F E; Mann, A; Chescoe, D; Price, S C; Nunn, A; Grasso, P; Bridges, J W

1986-01-01

195

A rapid low temperature method for preparation of methyl esters of fatty acids  

Microsoft Academic Search

A rapid method for preparation of methyl esters of fatty acids in lipids has been accomplished by forming the sulfuric acid\\u000a complex of the lipid in ethyl ether at the temp of a dry ice-acetone bath. Decomposition of the complex with methanol results\\u000a in direct formation of methyl esters of the fatty acids. A comparison was made of gas liquid

Gertrude W. McGinnis; L. R. Dugan

1965-01-01

196

The Preparation of Fatty Acid Esters by Means of Catalytic Reactions  

Microsoft Academic Search

A review of actually available techniques for the preparation of esters derived form natural oils and fats is presented. A wide choice of catalysts, either homogeneous or heterogeneous, is currently available. This paper evaluates in detail the possibilities for the preparation of fatty acid esters with different alcohols and discusses the criteria for a correct choice. The different problems related

Paolo Bondioli

2004-01-01

197

Water chemical ionization mass spectrometry of aldehydes, ketones esters, and carboxylic acids  

Microsoft Academic Search

Chemical ionization mass spectrometry (CI) of aliphatic and aromatic carbonyl compounds using water as the reagent gas provides intense pseudomolecular ions and class-specific fragmentation patterns that can be used to identify aliphatic aldehydes, ketones, carboxylic acids, and esters. The length of ester acyl and alkyl groups can easily be determined on the basis of loss of alcohols from the protonated

Steven B. Hawthorne; David J. Miller

1986-01-01

198

The ecotoxicity and the biodegradability of lactic acid, alkyl lactate esters and lactate salts  

Microsoft Academic Search

The ecotoxicity of lactic acid, its alkyl esters and selected metal salts was studied experimentally with the micro alga Selenastrum capricornutum, the crustacean Daphnia magna and the fish species Brachydanio rerio and Pimephales promelas. In addition, the biodegradation of lactate esters was also studied. The aim of the study was to provide predicted environmental data for additional alkyl homologues and

C. T. Bowmer; R. N. Hooftman; A. O. Hanstveit; P. W. M. Venderbosch; N. van der Hoeven

1998-01-01

199

ENZYMATIC SYNTHESIS OF A GALACTOPYRANOSE SOPHOROLIPID FATTY ACID-ESTER  

Technology Transfer Automated Retrieval System (TEKTRAN)

A C18:1 sophorolipid lactone produced by the yeast Candida bombicola was deacetylated and ring opened with sodium methoxide to the methyl ester form. After re-acetylation with vinyl acetate using an immobilized lipase, the methyl ester was transesterified with 1,2-3,4-di-O-isopropylidene-D-galactop...

200

Enhancement of Emulsifying Properties of Cuttlefish Skin Gelatin by Modification with N -hydroxysuccinimide Esters of Fatty Acids  

Microsoft Academic Search

Cuttlefish (Sepia pharaonis) skin gelatin modified with N-hydroxysuccinimide esters of various fatty acids including capric acid (C10:0), lauric acid (C12:0), and myristic acid (C14:0)\\u000a at different molar ratios was characterized and determined for emulsifying property. Fatty acid esters were incorporated into\\u000a gelatin as indicated by the decrease in free amino group content. Gelatin modified with fatty acid ester had the

Tanong Aewsiri; Soottawat Benjakul; Wonnop Visessanguan; Angel B. Encarnacion; Peter A. Wierenga; Harry Gruppen

201

Manipulating Membrane Fatty Acid Compositions of Whole Plants with Tween-Fatty Acid Esters 1  

PubMed Central

This paper describes a method for manipulating plant membrane fatty acid compositions without altering growth temperature or other conditions. Tween-fatty acid esters carrying specific fatty acids were synthesized and applied to various organs of plants growing axenically in glass jars. Treated plants incorporated large amounts of exogenous fatty acids into all acylated membrane lipids detected. Fatty acids were taken up by both roots and leaves. Fatty acids applied to roots were found in leaves, while fatty acids applied to leaves appeared in both leaves higher on the plant and in roots, indicating translocation (probably in the phloem). Foliar application was most effective; up to 20% of membrane fatty acids of leaves above the treated leaf and up to 40% of root membrane fatty acids were exogenously derived. Plants which took up exogenous fatty acids changed their patterns of fatty acid synthesis such that ratios of saturated to unsaturated fatty acids remained essentially unaltered. Fatty acid uptake was most extensively studied in soybean (Glycine max [L.] Merr.), but was also observed in other species, including maize (Zea mays L.), mung beans (Vigna radiata L.), peas (Pisum sativum L.), petunia (Petunia hybrida L.) and tomato (Lycopersicon esculentum Mill.). Potential applications of this system include studying internal transport of fatty acids, regulation of fatty acid and membrane synthesis, and influences of membrane fatty acid composition on plant physiology. Images Figure 2

Terzaghi, William B.

1989-01-01

202

Characterization of modified calcium-silicate cements exposed to acidic environment  

SciTech Connect

Portland cement which is used as a binder in concrete in the construction industry has been developed into a biomaterial. It is marketed as mineral trioxide aggregate and is used in dentistry. This material has been reported to be very biocompatible and thus its use has diversified. The extended use of this material has led to developments of newer versions with improved physical properties. The aim of this study was to evaluate the effect of acidic environments found in the oral cavity on fast setting calcium silicate cements with improved physical properties using a combination of techniques. Two fast setting calcium silicate cements (CSA and CFA) and two cement composites (CSAG and CFAG) were assessed by subjecting the materials to lactic acid/sodium lactate buffer gel for a period of 28 days. At weekly intervals the materials were viewed under the tandem scanning confocal microscope (TSM), and scanning electron microscope (SEM). The two prototype cements exhibited changes in their internal chemistry with no changes in surface characteristics. Since the changes observed were mostly sub-surface evaluation of surface characteristics of cement may not be sufficient in the determination of chemical changes occurring. - Research Highlights: {yields} An acidic environment affects modified fast setting calcium silicate-based cements. {yields} No surface changes are observed in acidic environment. {yields} An acidic environment causes sub-surface changes in the material chemistry which are only visible in fractured specimens. {yields} A combination of techniques is necessary in order to evaluate the chemical changes occurring.

Camilleri, Josette, E-mail: josette.camilleri@um.edu.mt

2011-01-15

203

Calculation of 29Si NMR shifts of silicate complexes with carbohydrates, amino acids, and muhicarboxylic acids: potential role in biological silica utilization  

Microsoft Academic Search

The existence of ether or ester-like complexes of silicate with organic compounds has long been debated in the literature on biological utilization of silicon. Comparison of theoretically calculated 29Si NMR chemical shifts for such complexes with experimentally measured values in biological systems could provide a diagnostic tool for identifying which, if any of these molecules exist under physiological conditions. Results

Nita Sahai

2004-01-01

204

Fatty acid ethyl esters. Ethanol metabolites that reflect ethanol intake.  

PubMed

Fatty acid ethyl esters (FAEEs) are nonoxidative ethanol metabolites that have been implicated as mediators of alcohol-induced organ damage. FAEEs are detectable in the blood after ethanol ingestion, and on that basis represent markers of ethanol intake. FAEEs have also been quantitated in human liver and adipose tissue and have been shown to be postmortem markers of premortem ethanol intake. A substantial difference in FAEE concentration was found in liver and adipose tissue of patients with detectable blood ethanol at the time of autopsy vs those with no detectable blood ethanol, who were either chronic alcoholics or social drinkers. Most currently available diagnostic markers for chronic alcoholism have limited clinical utility. Data in this report demonstrate that the amount or type of FAEEs can be used to differentiate a chronic alcoholic from an episodic heavy drinker (binage drinker) at or near peak blood ethanol concentrations and approximately 24 hours after discontinuation of ethanol. Thus, FAEEs are markers of ethanol intake in blood and tissues and can be useful in distinguishing chronic alcoholics from binge drinkers. PMID:12951847

Soderberg, Britt L; Salem, Raneem O; Best, Catherine A; Cluette-Brown, Joanne E; Laposata, Michael

2003-06-01

205

Automated determination of fatty acid methyl ester and cis\\/ trans methyl ester composition of fats and oils  

Microsoft Academic Search

The determination of the fatty acid composition (as methyl esters, FAMEs) of fats and oils and their cis\\/trans (CTME) distribution requires a simple, but manual and time-consuming sample preparation. The so-called BF3 method is often the preferred procedure. Because FAME\\/CTME analyses are encountered very frequently in the food industry, an automated, robot-based alternative is proposed which uses the sodium methylate

Sjaak de Koning; Bram van der Meer; Geert Alkema; Hans-Gerd Janssen; Udo A. Th Brinkman

2001-01-01

206

Automated determination of fatty acid methyl ester and cis/trans methyl ester composition of fats and oils.  

PubMed

The determination of the fatty acid composition (as methyl esters, FAMEs) of fats and oils and their cis/trans (CTME) distribution requires a simple, but manual and time-consuming sample preparation. The so-called BF3 method is often the preferred procedure. Because FAME/CTME analyses are encountered very frequently in the food industry, an automated, robot-based alternative is proposed which uses the sodium methylate procedure. After sample weighing and the (manual) addition of heptane (2 min), a XYZ robotic autosampler is used for all remaining work, which includes reagent addition, agitation, sample settling and the final injection into the gas chromatograph (10 min). The performance of the sodium methylate and BF3 methods are compared by analysing some 30 oil and fat samples. The novel procedure is much faster (less than 15 min versus ca. 1 h) and manual sample handling is drastically decreased. The experimental results obtained with the two methods frequently are the same, while small differences can be explained by (known) differences of the two methods in the conversion of minor oil/fat constituents, such as free fatty acids, wax esters and sterol esters. In case of FAME analyses, a hot injection is to be preferred over a cold injection. The RSDs of the peak areas were 1.5% for the major fatty acids to 11% for peaks that were just above the noise level. The detection limit were approximately 0.03%. PMID:11486889

de Koning, S; van der Meer, B; Alkema, G; Janssen, H G; Brinkman, U A

2001-07-13

207

Concentration of Stearidonic Acid in Free Fatty Acid and Fatty Acid Ethyl Ester Forms from Modified Soybean Oil by Winterization  

Microsoft Academic Search

The concentration of stearidonic acid (SDA, 18:4 ?-3) in free fatty acid (FFA) and fatty acid ethyl ester (FAEE) forms by\\u000a low temperature crystallization (winterization) was studied. For this purpose, modified soybean oil (initial SDA content,~23%)\\u000a was transformed into its corresponding FFA and FAEE by chemical hydrolysis and ethanolysis, respectively. In the first study,\\u000a the FFA and FAEE were used

Luis Vzquez; Casimir C. Akoh

208

Desorption of arsenic from clay and humic acid-coated clay by dissolved phosphate and silicate  

NASA Astrophysics Data System (ADS)

Arsenic (As) contaminated aquifers contain iron minerals and clays that strongly bind As at their surfaces. It was suggested that As mobilization is driven by natural organic matter (including fulvic acids (FA) and humic acids (HA)) present in the aquifers either via providing reducing equivalents for reductive dissolution of Fe(III) (hydr)oxides or via competitive desorption of As from the mineral surfaces. In the present study we quantified sorption of As(III) and As(V) to Ca2+-homoionized illite (IL) and to kaolinite (Kao) as well as to HA-coated clays, i.e., illite-HA (IL-HA) and kaolinite-HA (Kao-HA) at neutral pH. Clay-HA complexes sorbed 28-50% more As than clay-only systems upon addition of 100 ?M As(III)/As(V) to 0.5 g of clay or HA-clay with Ca2+ probably playing an important role for HA binding to the clay surface and As binding to the HA. When comparing sorption of As(V) and As(III) to clay and HA-clay complexes, As(V) sorption was generally higher by 15-32% than sorption of As(III) to the same complexes. IL and IL-HA sorbed 11-28% and 6-11% more As compared to Kao and Kao-HA, respectively. In a second step, we then followed desorption of As from Kao, Kao-HA, IL and IL-HA by 100 and 500 ?M phosphate or silicate both at high (0.41-0.77 ?mol As/g clay), and low (0.04 to 0.05 ?mol As/g clay) As loadings. Phosphate desorbed As to a larger extent than silicate regardless of the amount of As loaded to clay minerals, both in the presence and absence of HA, and both for illite and kaolinite. At high loadings of As, the desorption of both redox species of As from clay-HA complexes by phosphate/silicate ranged from 32 to 72% compared to 2-54% in clay only systems meaning that As was desorbed to a larger extent from HA-coated clays compared to clay only systems. When comparing As(III) desorption by phosphate/silicate to As(V) desorption in high As-loading systems, there was no clear trend for which As species is desorbed to a higher extent in the four clay systems meaning that both As species behave similarly regarding desorption from clay surfaces by phosphate/silicate. Similarly, no significant differences were found in high As-loading systems in the amount of As desorbed by phosphate/silicate when comparing Kao vs. IL and Kao-HA vs IL-HA systems meaning that both clay types behave similarly regarding desorption of As by phosphate/silicate. At low As loadings, up to 80% of As was desorbed by phosphate and silicate with no noticeable differences being observed between different As species, different types of clay, clay vs clay-HA or the type of desorbant (phosphate and silicate). The results of this study showed that HA sorption to Ca2+-homoionized clay minerals can increase As binding to the clay although the As sorbed to the clay-HA is also released to a greater extent by competing ions such as phosphate and silicate. Desorption of As depended on the initial loadings of As onto the clay/clay-HA. Based on our results, the effect of humic substances on sorption of As and on desorption of As by phosphate and silicate has to be considered in order to fully understand and evaluate the environmental behavior of As in natural environments.

Sharma, Prasesh; Kappler, Andreas

2011-11-01

209

Process for Preserving Raw Fruits and Vegetables Using Ascorbic Acid Esters and Compositions Thereof.  

National Technical Information Service (NTIS)

The invention relates to the preservation of raw fruits, vegetables and their juices. More particularly, the invention relates to the use of certain ascorbic acid esters, and compositions thereof, to control enzymatic browning in raw fruit and vegetable p...

G. M. Sapers K. B. Hicks P. A. Seib

1987-01-01

210

Pattern Recognition Applications in Chemistry and Pharmacology. III. Clustering of Substituted Glycolic Acid Esters (Glycolates).  

National Technical Information Service (NTIS)

A computerized pseudoclustering algorithm (SIMP) was written and applied to 12 chemical structure descriptors (features) which, on the basis of expert opinion, are required for substituted glycolic acid esters (glycolates) to have some type of physiologic...

W. J. Sacco E. W. Strovel D. E. Renard P. H. Broome W. P. Ashman

1978-01-01

211

Process for Preserving Raw Fruits and Vegetables Using Ascorbic Acid Esters and Compositions Thereof.  

National Technical Information Service (NTIS)

The present invention relates to the preservation of raw fruits, vegetables and their juices. More particularly, the present invention relates to the use of certain ascorbic acid esters, and compositions thereof, to control enzymatic browning in raw fruit...

G. M. Sapers K. B. Hicks P. A. Seib

1987-01-01

212

Comparative Oxidative Stability of Fatty Acid Alkyl Esters by Accelerated Methods  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several fatty acid alkyl esters were subjected to accelerated methods of oxidation, including EN 14112 (Rancimat method) and pressurized differential scanning calorimetry (PDSC). Structural trends elucidated from both methods that improved oxidative stability included decreasing the number of doubl...

213

Premixed ignition behavior of C{sub 9} fatty acid esters: A motored engine study  

SciTech Connect

An experimental study on the premixed ignition behavior of C{sub 9} fatty acid esters has been conducted in a motored CFR engine. For each test fuel, the engine compression ratio was gradually increased from the lowest point (4.43) to the point where significant high temperature heat release (HTHR) was observed. The engine exhaust was sampled and analyzed through GC-FID/TCD and GC-MS. Combustion analysis showed that the four C{sub 9} fatty acid esters tested in this study exhibited evidently different ignition behavior. The magnitude of low temperature heat release (LTHR) follows the order, ethyl nonanoate > methyl nonanoate >> methyl 2-nonenoate > methyl 3-nonenoate. The lower oxidation reactivity for the unsaturated fatty acid esters in the low temperature regime can be explained by the reduced amount of six- or seven-membered transition state rings formed during the oxidation of the unsaturated esters due to the presence of a double bond in the aliphatic chain of the esters. The inhibition effect of the double bond on the low temperature oxidation reactivity of fatty acid esters becomes more pronounced as the double bond moves toward the central position of the aliphatic chain. GC-MS analysis of exhaust condensate collected under the engine conditions where only LTHR occurred showed that the alkyl chain of the saturated fatty acid esters participated in typical paraffin-like low temperature oxidation sequences. In contrast, for unsaturated fatty acid esters, the autoignition can undergo olefin ignition pathways. For all test compounds, the ester functional group remains largely intact during the early stage of oxidation. (author)

Zhang, Yu.; Yang, Yi; Boehman, Andre L. [EMS Energy Institute, The Pennsylvania State University, University Park, PA 16802 (United States)

2009-06-15

214

A new, direct analytical method using LCMS\\/MS for fatty acid esters of 3-chloro-1,2-propanediol (3-MCPD esters) in edible oils  

Microsoft Academic Search

A new, direct analytical method for the determination of 3-chloro-1,2-propanediol fatty acid esters (3-MCPD esters) was developed. The targeted 3-MCPD esters included five types of monoester and 20 types of diester. Samples (oils and fats) were dissolved in a mixture of tert-butyl methyl ether and ethyl acetate (4:1), purified using two solid-phase extraction (SPE) cartridges (C18 and silica), then analysed

K. Yamazaki; M. Ogiso; S. Isagawa; T. Urushiyama; T. Ukena; N. Kibune

2012-01-01

215

Lipase-catalyzed synthesis of lesquerolic acid wax and diol esters and their properties  

Microsoft Academic Search

Lesquerolic acid was and ?,?-diol esters were synthesized via immobilizedRhizomucor miehei lipase-(Lipozyme) catalyzed esterification of lesquerolic acid and alcoholysis of lesquerella oil. For each wax ester synthesis,\\u000a when alcohol substrate was present at a slight (ca. 20%) stoichiometric excess and water content was kept low, over 94% of\\u000a the hydroxy acyl groups were esterified. The extent of reaction and the

Douglas G. Hayes; Robert Kleiman

1996-01-01

216

A novel Aspergillus oryzae esterase that hydrolyzes 4-hydroxybenzoic acid esters.  

PubMed

In this study we report the biochemical characterization of a hypothetical protein from Aspergillus oryzae exhibiting sequence identity with feruloyl esterase and tannase from the genus Aspergillus. The purified recombinant protein showed a hydrolytic activity toward the ethyl, propyl, or butyl esters of 4-hydroxybenzoic acid, but did not show feruloyl esterase or tannase activity. Finally, the enzyme decreased the antimicrobial activity of parabens against A. oryzae via hydrolysis of the ester bond present in butyl 4-hydroxybenzoic acid. PMID:20728445

Koseki, Takuya; Mihara, Koji; Murayama, Tetsuya; Shiono, Yoshihito

2010-08-20

217

(Z)-selective ?-bromination ofN-formyl-?, ?-dehydroamino acid esters  

Microsoft Academic Search

Stereoselective ?-bromination ofN-formyl-?, ?-dehydroamino acid esters5 was investigated. A reaction of5 with NBS afforded?-bromo-N-formylimines10 which successively isomerized to give?-bromo-N-formyl-?, ?-dehydroamino acid esters4. The migration of the double bond of the intermediates10 with bulky substituents at the ?-position resulted in highly stereoselective formation of(Z)-4, while that of the substrates with less bulky substituents proceeded non-stereoselectively. A mechanism of the stereoselective bromination

Masaki Yamada; Kazuya Nakao; Toshio Fukui; Ken-ichi Nunami

1996-01-01

218

Transesterification of Fish Oil to Produce Fatty Acid Ethyl Esters Using Ultrasonic Energy  

Microsoft Academic Search

This study evaluated the production of fatty acid ethyl esters from fish oil using ultrasonic energy and alkaline catalysts\\u000a dissolved in ethanol. The feasibility of fatty acid ethyl ester production was determined using an ultrasonic bath and probe,\\u000a and between 0.5 and 1% KOH (added to the fish oil). Furthermore, factors such as ultrasonic device (bath and probe), catalyst\\u000a (KOH

Roberto E. Armenta; Mircea Vinatoru; Adam M. Burja; Jaroslav A. Kralovec; Colin J. Barrow

2007-01-01

219

Emulsification properties of polyesters and sucrose ester blends I: Carbohydrate fatty acid polyesters  

Microsoft Academic Search

A number of carbohydrate fatty acid polyesters, potential fat substitutes, were screened for their ability to reduce surface\\u000a and interfacial tensions alone or as blends with commercial emulsifiers. Commercial sucrose ester emulsifiers (Ryoto, Mitsubishi-Kasei\\u000a Food Corporation, Tokyo, Japan) were evaluated alone or blended with other sucrose esters or with other carbohydrate fatty\\u000a acid polyesters, and their surfactant properties were examined

Casimir C. Akoh

1992-01-01

220

Application of sucrose fatty acid ester to reverse micellar extraction of lysozyme  

Microsoft Academic Search

Reverse micellar extraction of lysozyme has been carried out using an organic solution containing a mixture of monoester and polyester of sucrose fatty acid ester. The forward extraction of lysozyme from the feed aqueous phase to the reverse micellar organic phase of the mixture of monoester and polyester of sucrose fatty acid ester at pH7.2 was strongly dependent upon the

Hidetaka Noritomi; Hiroshi Kowata; Naoki Kojima; Satoru Kato; Kunio Nagahama

2006-01-01

221

Effect of composition of sucrose fatty acid esters on formation of palladium nanoparticles in reverse micelles  

Microsoft Academic Search

Palladium (Pd) nanoparticles were prepared in the reverse micellar system containing sucrose fatty acid esters with various\\u000a esterification degrees. The TEM showed that Pd nanoparticles were of spherical and relatively uniform. The size of Pd nanoparticles\\u000a strongly depended upon the composition of sucrose fatty acid esters. The resultant Pd colloid could be preserved for at least\\u000a 2months without precipitation.

Hidetaka Noritomi; Kenji Kagitani; Yasutaka Muratsubaki; Satoru Kato

2009-01-01

222

Investigation of the reaction of phenyl radicals with phenyl esters of thiocabboxylic acids  

Microsoft Academic Search

1.Phenyl radicals add to the phenyl esters of thiocarboxylic acids (R=Ph, Ph2CH, PhCH2) at the sulfur atom of the C=S group with the formation of radical-adducts of the type, which were identified by ESR using a spin trap technique.2.The radical-adduct Ph2 is converted into the O,S-bis-phenylacetal of diphenylketene and the phenyl ester of diphenylthioacetic acid while the radical-adduct is converted

R. G. Petrova; R. G. Gasanov; T. D. Churkina; V. I. Dostovalova; R. Kh. Freidlina

1984-01-01

223

Sugar fatty acid ester surfactants: Structure and ultimate aerobic biodegradability  

Microsoft Academic Search

Ultimate aerobic biodegradabilities of an array of sugar ester surfactants were determined by International Standards Organisation\\u000a method 7827, Water QualityEvaluation in an Aqueous Medium of the Aerobic Biodegradability of Organic Compounds, Method by\\u000a Dissolved Organic Carbon (1984). The surfactants were nonionic sugar esters with different-sized sugar head groups (formed\\u000a from glucose, sucrose, or raffinose) and different lengths and numbers of

Irene J. A. Baker; Barry Matthews; Hector Suares; Irena Krodkiewska; D. Neil Furlong; Franz Grieser; Calum I. Drummond

2000-01-01

224

Ammonolysis of esters of hydroxybenzoic acids on a boron phosphate catalyst  

SciTech Connect

In this investigation boron phosphate catalyst was used for ammonolysis of methyl and ethyl esters of salicylic and 4-hydroxybenzoic acids. It was shown that ammonolysis of methyl and ethyl esters of salicylic and 4-hydroxybenzoic acids in presence of boron phosphate catalyst at a ratio of 3-7 moles of ammonia per mole of ester in a contact time of 1-5 sec at 380-400/sub 0/ can be used for obtaining o- and p- hydroxybenzonitriles in yields of over 90% of the theoretical.

Suvorov, B.V.; Bukeikhanov, N.R.; Li, L.V.; Zulkasheva, A.Z.

1987-09-10

225

Improved Biodegradation and Thermal Properties of Poly(lactic acid)\\/Layered Silicate Nanocomposites  

Microsoft Academic Search

Poly(lactic acid) (PLA)\\/layered silicate nanocomposites have successfully been prepared using the solution route. Two types of organically modified nanoclays, namely, MEE and MAE have been used. The nanostructure, as observed from wide angle X-ray diffraction, indicates an intercalated hybrid for both PLAMEE and PLAMAE, and depends on the type of organic modifier used. Intercalation is higher in PLAMEE as compared

Muktikanta Panigrahi; Narendra K. Singh; Rajeev K. Gautam; Rathindra M. Banik; Pralay Maiti

2010-01-01

226

The Use of Fatty Acid Esters to Enhance Free Acid Sophorolipid Synthesis  

Microsoft Academic Search

Fatty acid esters were prepared by transesterification of soy oil with methanol (methyl-soyate, Me-Soy), ethanol (ethyl-soyate,\\u000a Et-Soy) and propanol (propyl-soyate, Pro-Soy) and used with glycerol as fermentation substrates to enhance production of free-acid\\u000a sophorolipids (SLs). Fed-batch fermentations of Candida bombicola resulted in SL yields of 46 4g\\/l, 42 7g\\/l and 18 6g\\/l from Me-Soy, Et-Soy, and Pro-Soy, respectively. Liquid chromatography

Richard D. Ashby; Daniel K. Y. Solaiman; Thomas A. Foglia

2006-01-01

227

Novel fatty acid esters of p-coumaryl alcohol in epicuticular wax of apple fruit.  

PubMed

Hexane extracts of epicuticular wax from cv. Gala apples were noted to have an unusual, broad absorbance maximum at approximately 258 nm, which led us to isolate and identify the primary UV-absorbing compounds. Column and thin-layer chromatography yielded a fraction that gave a series of paired, 260-nm-absorbing peaks on C(18) HPLC. These were shown to be a family of phenolic fatty acid esters, for which retention times increased with increasing fatty acid chain length, and paired peaks were esters of two related phenolics with the same fatty acid moiety. Alkaline hydrolysis of the esters released two water-soluble phenolics separable by C(18) HPLC. Electrospray ionization mass spectrometry gave a molecular mass of 150 for both, and (1)H NMR plus UV absorbance spectra identified them as E and Z isomers of p-coumaryl alcohol. Alkaline cleavage of the fatty acid esters in the presence of methanol or ethanol resulted in partial derivatization of E-p-coumaryl alcohol to the corresponding gamma-O-methyl or O-ethyl ether. Gradient HMQC NMR of the HPLC-purified stearate ester of E-p-coumaryl alcohol indicated that fatty acid esterification occurs at the gamma-OH rather than at the 4-OH on the phenyl ring. This is the first report of fatty acid esters of monolignols as a natural plant product. PMID:11513667

Whitaker, B D; Schmidt, W F; Kirk, M C; Barnes, S

2001-08-01

228

Engineering of Candida antarctica lipase B for hydrolysis of bulky carboxylic acid esters.  

PubMed

Candida antarctica lipase B (CALB) is a widely used biocatalyst with high activity and specificity for a wide range of primary and secondary alcohols. However, the range of converted carboxylic acids is more narrow and mainly limited to unbranched fatty acids. To further broaden the biotechnological applications of CALB it is of interest to expand the range of converted carboxylic acid and extend it to carboxylic acids that are branched or substituted in close proximity of the carboxyl group. An in silico library of 2400 CALB variants was built and screened in silico by substrate-imprinted docking, a four step docking procedure. First, reaction intermediates of putative substrates are covalently docked into enzyme active sites. Second, the geometry of the resulting enzyme-substrate complex is optimized. Third, the substrate is removed from the complex and then docked again into the optimized structure. Fourth, the resulting substrate poses are rated by geometric filter criteria as productive or non-productive poses. Eleven enzyme variants resulting from the in silico screening were expressed in Escherichia coli BL21 and measured in the hydrolysis of two branched fatty acid esters, isononanoic acid ethyl ester and 2-ethyl hexanoic acid ethyl esters. Five variants showed an initial increase in activity. The variant with the highest wet mass activity (T138S) was purified and further characterized. It showed a 5-fold increase in hydrolysis of isononanoic acid ethyl ester, but not toward sterically more demanding 2-ethyl hexanoic acid ethyl ester. PMID:20887757

Juhl, P B; Doderer, K; Hollmann, F; Thum, O; Pleiss, J

2010-09-29

229

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters  

DOEpatents

A process of preparing an acid addition salt of delta-aminolevulinic acid comprising: dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures thereof to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing said alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Moens, Luc (Lakewood, CO)

1999-01-01

230

Synthesis of an acid addition salt of delta-aminolevulinic acid from 5-bromo levulinic acid esters  

DOEpatents

A process is disclosed for preparing an acid addition salt of delta-aminolevulinic acid comprising. The process involves dissolving a lower alkyl 5-bromolevulinate and an alkali metal diformylamide in an organic solvent selected from the group consisting of acetonitrile, methanol, tetrahydrofuran, 2-methyltetrahydrofuran and methylformate or mixtures to form a suspension of an alkyl 5-(N,N-diformylamino) levulinate ester; and hydrolyzing the alkyl 5-(N,N-diformylamino) levulinate with an inorganic acid to form an acid addition salt of delta-amino levulinic acid.

Moens, L.

1999-05-25

231

Lewis acid catalysis of photochemical reactions. 4. Selective isomerization of cinnamic esters  

SciTech Connect

The spectroscopic properties and photoisomerization reactions of several (E)- and (Z)-cinnamic esters, bis cinnamic esters, and model esters and lactones in the presence and absence of Lewis acids have been investigated. The use of Lewis acids such as BF/sub 3/ or EtAlCl/sub 2/ results in enhanced photoisomerization efficiency and a shift in the photoequilibrium toward the thermodynamically less stable Z isomer. Enhanced E ..-->.. Z photoisomerization results from selective excitation of ground-state ester-Lewis acid complexes. These complexes have been characterized by /sup 1/H NMR, ultraviolet, and fluorescence spectroscopies. The equilibrium constants for complexation are dependent upon both the electron donor strength of the ester and its conformational mobility. These factors also determine the magnitude of the red shifts in the electronic absorption spectra observed upon complexation. Enhanced E ..-->.. Z photoisomerization upon complex formation is a consequence of selective excitation of the E vs. Z complex, more efficient isomerization of the excited E vs. Z complex, and larger equilibrium constants for complexation of E vs. Z esters. The photoequilibria obtained for bis cinnamic esters are highly enriched in the Z,Z and Z,E isomers in accord with independent isomerization of the two cinnamate groups; however, in the case of 1,3-trimethylenebis(cinnamate), two-bond isomerization of the E,E to Z,Z isomer is observed at low conversions.

Lewis, F.D.; Oxman, J.D.; Gibson, L.L.; Hampsch, H.L.; Quillen, S.L.

1986-05-28

232

Determination of the carbon deficiency in the flame ionization detector response of long-chain fatty acid methyl esters and dicarboxylic acid dimethyl esters.  

PubMed

Carbon deficiencies (CDs) of long-chain fatty acid methyl esters (FAMEs) and dicarboxylic acid dimethyl esters (DDMEs), which lead to decreased response in a flame ionization detection (FID) system, were determined by using full responding hydrocarbons (heptadecane, eicosane and alpha-cholestane) as references. For saturated FAMEs ranging from C12 to C22 and for DDMEs ranging from C4 to C10, CDs between 1.3+/-0.12 and 1.7+/-0.36 per ester group were recorded. All values were significantly (P < 0.05) greater than 1. Generally, response factors for gas-chromatographic analysis using FID have been calculated on the theory that the CD of FAMEs is 1 per ester group. However, this theory could not be confirmed experimentally for short-chain FAMEs of less than 8 carbons as CDs of around 1.5 were reported for C4 and C6 FAMEs. The study presented here contributes an approach to this problem by confirming the validity of response factors calculated from a CD of 1.5 per ester group as well as for long-chain FAMEs and DDMEs. PMID:15378895

Schreiner, Matthias; Hulan, Howard W

2004-08-01

233

Branched Chain Amino Acid Metabolism in the Biosynthesis of Lycopersicon pennellii Glucose Esters.  

PubMed

Lycopersicon pennellii Corr. (D'Arcy) an insect-resistant, wild tomato possesses high densities of glandular trichomes which exude a mixture of 2,3,4-tri-O-acylated glucose esters that function as a physical impediment and feeding deterrent to small arthropod pests. The acyl moieties are branched C(4) and C(5) acids, and branched and straight chain C(10), C(11), and C(12) acids. The structure of the branched acyl constituents suggests that the branched chain amino acid biosynthetic pathway participates in their biosynthesis. [(14)C]Valine and deuterated branched chain amino acids (and their oxo-acid derivatives) were incorporated into branched C(4) and C(5) acid groups of glucose esters by a process of transamination, oxidative decarboxylation and subsequent acylation. C(4) and C(5) branched acids were elongated by two carbon units to produce the branched C(10)-C(12) groups. Norvaline, norleucine, allylglycine, and methionine also were processed into acyl moieties and secreted from the trichomes as glucose esters. Changes in the acyl composition of the glucose esters following sulfonylurea herbicide administration support the participation of acetohydroxyacid synthetase and the other enzymes of branched amino acid biosynthesis in the production of glucose esters. PMID:16667654

Walters, D S; Steffens, J C

1990-08-01

234

Branched chain amino acid metabolism in the biosynthesis of Lycopersicon pennellii glucose esters  

SciTech Connect

Lycopersicon pennellii Corr. (D'Arcy) an insect-resistant, wild tomato possesses high densities of glandular trichomes which exude a mixture of 2,3,4-tri-O-acylated glucose esters that function as a physical impediment and feeding deterrent to small arthropod pests. The acyl moieties are branched C{sub 4} and C{sub 5} acids, and branched and straight chain C{sub 10}, C{sub 11}, and C{sub 12} acids. The structure of the branched acyl constituents suggests that the branched chain amino acid biosynthetic pathway participates in their biosynthesis. ({sup 14}C)Valine and deuterated branched chain amino acids (and their oxo-acid derivatives) were incorporated into branched C{sub 4} and C{sub 5} acid groups of glucose esters by a process of transamination, oxidative decarboxylation and subsequent acylation. C{sub 4} and C{sub 5} branched acids were elongated by two carbon units to produce the branched C{sub 10}-C{sub 12} groups. Norvaline, norleucine, allylglycine, and methionine also were processed into acyl moieties and secreted from the trichomes as glucose esters. Changes in the acyl composition of the glucose esters following sulfonylurea herbicide administration support the participation of acetohydroxyacid synthetase and the other enzymes of branched amino acid biosynthesis in the production of glucose esters.

Walters, D.S.; Steffens, J.C. (Cornell Univ., Ithaca, NY (USA))

1990-08-01

235

Branched Chain Amino Acid Metabolism in the Biosynthesis of Lycopersicon pennellii Glucose Esters 1  

PubMed Central

Lycopersicon pennellii Corr. (D'Arcy) an insect-resistant, wild tomato possesses high densities of glandular trichomes which exude a mixture of 2,3,4-tri-O-acylated glucose esters that function as a physical impediment and feeding deterrent to small arthropod pests. The acyl moieties are branched C4 and C5 acids, and branched and straight chain C10, C11, and C12 acids. The structure of the branched acyl constituents suggests that the branched chain amino acid biosynthetic pathway participates in their biosynthesis. [14C]Valine and deuterated branched chain amino acids (and their oxo-acid derivatives) were incorporated into branched C4 and C5 acid groups of glucose esters by a process of transamination, oxidative decarboxylation and subsequent acylation. C4 and C5 branched acids were elongated by two carbon units to produce the branched C10-C12 groups. Norvaline, norleucine, allylglycine, and methionine also were processed into acyl moieties and secreted from the trichomes as glucose esters. Changes in the acyl composition of the glucose esters following sulfonylurea herbicide administration support the participation of acetohydroxyacid synthetase and the other enzymes of branched amino acid biosynthesis in the production of glucose esters.

Walters, Donald S.; Steffens, John C.

1990-01-01

236

Stability of sucrose fatty acid esters under acidic and basic conditions.  

PubMed

The stability of sucrose fatty acid monoesters toward hydrolysis under acidic and basic conditions was evaluated. Mass spectrometric analysis of hydrolysates showed that the glycosidic bond was preferentially hydrolyzed under acidic conditions, whereas the ester bond was selectively hydrolyzed under basic conditions. Under both conditions, the rate of hydrolysis depended on the pH of the solution, the concentration of sucrose monoesters, and the acylated position of the sucrose monoesters. The hydrolysis of the glycosidic bond under acidic conditions was shown to be a first-order process. The rate constants for hydrolysis at various temperatures were measured, and the activation energies were calculated from the slope of the Arrhenius plots. The lifetime of sucrose monoesters estimated from the first-order rate constant for the hydrolysis reaction revealed that the sucrose monoesters have excellent long-term stability over a pH range of 5 to 7 at room temperature. PMID:21606619

Okumura, Haruo; Kitazawa, Naoki; Wada, Shoichi; Hotta, Hiroshi

2011-01-01

237

Spectroscopy of polyenes. 5. Absorption and emission spectral properties of polyene acids/esters related to retinoic acid/ester as homologues  

SciTech Connect

A number of all-trans polyene acids and esters with chain lengths varying over a range including two longer and two shorter homologues of retinoic acid/ester have been studied for their spectral and photophysical properties. The polyene acids form intermolecularly hydrogen-bonded dimers in nonpolar solvents (3-methylpentane and carbon tetrachloride). Upon increasing the polyene chain length as well as upon dimer formation (in the cases of the polyene acids), pronounced changes occur in the absorption-emission spectral maxima, infrared absorption frequencies (carbonyl and hydroxyl stretching), and fluorescence lifetimes and quantum yields. The photophysical dynamics is discussed in terms of a fluorescing state that is primarily of /sup 1/A/sub g/*/sup -/ character (dipole forbidden) in the longer polyene systems. 29 references, 5 figures, 2 tables.

Das, P.K. (Univ. of Notre Dame, IN); Becker, R.S.

1980-09-04

238

Gamma-aminobutyric acid esters. 1. Synthesis, brain uptake, and pharmacological studies of aliphatic and steroid esters of gamma-aminobutyric acid  

Microsoft Academic Search

Labeled and unlabeled aliphatic and steroid esters of gamma-amino(U-¹⁴C)butyric acid (GABA) were synthesized and tested for their capacity to penetrate the blood-brain barrier and for evidence of central neuropharmacological activity in rodents. The uptake of the labeled 9,12,15-octadecatrienyl (linolenyl), 3-cholesteryl, 1-butyl, and the 9-fluoro-11 beta,17-dihydroxy-16 alpha-methyl-3,20-dioxopregna -1,4-dien-21-yl (dexamethasone) esters of GABA into mouse brain increased 2-, 25-, 74-, and 81-fold

Victor E. Shashoua; James N. Jacob; Richard Ridge; Alexander Campbell; Ross J. Baldessarini

1984-01-01

239

Preparation and properties of esters of monohydric alcohols and fatty acids of tall oils  

Microsoft Academic Search

Esters of pure tall oil fatty acids and commercially available monohydric alcohols were prepared, distilled, and analyzed\\u000a for pertinent values. The tall oil fatty acid fraction used in the esterification contained approximately 0.6% rosin acids\\u000a with essentially equal distribution of fatty acids into oleic and linoleic acids. The use of various techniques, such as fast\\u000a cooling by the addition of

S. T. Bauer; Patricia R. Gill; R. E. Price

1961-01-01

240

Application of high vacuum fractional distillation to complex mixtures of methyl esters of polyunsaturated fatty acids  

Microsoft Academic Search

A technique for the high vacuum fractional distillation, with a spinning band column, of methyl esters of polyunsaturated\\u000a fatty acids employing a carrier of long chain acetates is described. The carrier is used to facilitate the fractionation of\\u000a minor components and minimize artifact formation in mixtures of methyl esters containing up to six double bonds. The technique\\u000a is demonstrated on

O. S. Privett; J. D. Nadenicek; F. J. Pusch; E. C. Nickell

1969-01-01

241

Synthesis of Substituted Phenyl Esters of Amino Acids and Polycondensation in Langmuirblodgett Films  

Microsoft Academic Search

Long-alkyl-chain phenyl esters of ?-alanine, glycine, and L-valine were prepared, and their monolayer properties were correlated with their molecular structures. These compounds formed stable monolayers on acidic subphases. In particular, the p-hexadecylphenyl esters of ?-alanine and glycine were remarkably stable, and their monolayers could be deposited on calcium fluoride plates as Y-type film by Blodgett's technique. The polycondensation of multilayers

Kenji Hanabusa; Takekazu Oumi; Toshiki Koyama; Hirofusa Shirai; Tadao Hayakawa; Akio Kurose

1989-01-01

242

Direct Determination of Glycidyl Esters of Fatty Acids in Vegetable Oils by LCMS  

Microsoft Academic Search

An LCMS method using a single quadrupole mass spectrometer was developed for direct analysis of glycidyl esters of fatty\\u000a acids in vegetable oils. Without any sample clean-up, this method provided acceptable recovery of seven glycidyl esters, comparable\\u000a results to a previously-published method utilizing two solid-phase extraction steps, and consistent detection parameters after\\u000a greater than 200 injections without any cleaning operations

Michael R. Blumhorst; Padmesh Venkitasubramanian; Mark W. Collison

2011-01-01

243

Biodegradation of phthalic acid esters in river water and activated sludge.  

PubMed Central

The primary and ultimate biodegradability of phthalic acid, monobutyl phthalate, and five structurally diverse phthalic acid ester plasticizers in river water and activated sludge samples were determined via ultraviolet spectrophotometry, gas chromatography, and CO2 evolution. The compounds studied underwent rapid primary biodegradation in both unacclimated river water and acclimated activated sludge. When activated sludge acclimated to phthalic acid esters was used as the inoculum for the CO2 evolution procedure, greater than 85% of the total theoretical CO2 was evolved. These studies demonstrate that the phthalic acid ester plasticizers and intermediate degradation products readily undergo ultimate degradation in different mixed microbial systems at concentrations ranging from 1 to 83 mg/liter.

Saeger, V W; Tucker, E S

1976-01-01

244

Enzymatic synthesis of sugar fatty acid esters in organic solvent and in supercritical carbon dioxide and their antimicrobial activity  

Microsoft Academic Search

Lipase-catalyzed synthesis of different sugar fatty acid esters was performed in high yields in 2-methyl-2-butanol at atmospheric pressure and in supercritical carbon dioxide (SC CO2) at 10MPa. Influence of molecular sieves concentration on conversion in SC CO2 was studied. Growth inhibitory effect of commercial sucrose fatty acid esters and enzymatically synthesized sucrose and fructose fatty acid esters on Gram-positive and

Maja Habulin; Saa abeder; eljko Knez

2008-01-01

245

Vapor-liquid equilibrium data for fatty acids and fatty methyl esters at low pressures  

Microsoft Academic Search

ConclusionsThe experimental vapor-liquid equilibrium data obtained with a mixture of methyl esters, and a mixture of a fatty acid and\\u000a the corresponding methyl ester, were in agreement with calculated Raoults law data at a pressure of 4.00.2 mm. Hg.\\u000a \\u000a The system lauric acid-myristic acid was observed to be non-ideal or not obeying Raoults law at a pressure of 4.00.2 mm.

J. A. Monick; H. D. Allen; C. J. Marlies

1946-01-01

246

Targeted delivery to PEPT1-overexpressing cells: acidic, basic, and secondary floxuridine amino acid ester prodrugs.  

PubMed

Floxuridine is a clinically proven anticancer agent in the treatment of metastatic colon carcinomas and hepatic metastases. However, prodrug strategies may be necessary to improve its physiochemical properties and selectivity and to reduce undesirable toxicity effects. Previous studies with amino acid ester prodrugs of nucleoside drugs targeted to the PEPT1 transporter coupled with recent findings of the functional expression of the PEPT1 oligopeptide transporter in pancreatic adenocarcinoma cell lines suggest the potential of PEPT1 as therapeutic targets for cancer treatment. In this report, we show the feasibility of achieving enhanced transport and selective antiproliferative action of amino acid ester prodrugs of floxuridine in cell systems overexpressing PEPT1. All prodrugs exhibited affinity for PEPT1 (IC50, 1.1-2.3 mmol/L). However, only the prolyl and lysyl prodrugs exhibited enhanced uptake (2- to 8-fold) with HeLa/PEPT1 cells compared with HeLa cells, suggesting that the aspartyl prodrugs are PEPT1 inhibitors. The selective growth inhibition of Madine-Darby canine kidney (MDCK)/PEPT1 cells over MDCK cells by the prodrugs was consistent with the extent of their PEPT1-mediated transport. All ester prodrugs hydrolyzed to floxuridine fastest in Caco-2 cell and MDCK homogenates and slower in human plasma and were most chemically stable in pH 6.0 buffer. Prolyl and lysyl prodrugs were relatively less stable compared with aspartyl prodrugs in buffers and in cell homogenates. The results suggest that optimal design for targeted delivery would be possible by combining both stability and transport characteristics afforded by the promoiety. PMID:15827340

Landowski, Christopher P; Vig, Balvinder S; Song, Xueqin; Amidon, Gordon L

2005-04-01

247

The use of fatty acid esters to enhance free acid sophorolipid synthesis.  

PubMed

Fatty acid esters were prepared by transesterification of soy oil with methanol (methyl-soyate, Me-Soy), ethanol (ethyl-soyate, Et-Soy) and propanol (propyl-soyate, Pro-Soy) and used with glycerol as fermentation substrates to enhance production of free-acid sophorolipids (SLs). Fed-batch fermentations of Candida bombicola resulted in SL yields of 46 +/- 4 g/l, 42 +/- 7 g/l and 18 +/- 6 g/l from Me-Soy, Et-Soy, and Pro-Soy, respectively. Liquid chromatography with atmospheric pressure ionization mass spectrometry (LC/API-MS) showed that Me-Soy resulted in 71% open-chain SLs with 59% of those molecules remaining esterified at the carboxyl end of the fatty acids. Et-Soy and Pro-Soy resulted in 43% and 80% open-chain free-acid SLs, respectively (containing linoleic acid and oleic acid as the principal fatty acid species linked to the sophorose sugar at the omega-1 position), with no evidence of residual esterification. PMID:16555009

Ashby, Richard D; Solaiman, Daniel K Y; Foglia, Thomas A

2006-02-01

248

Fuel and lubricant additives from acid treated mixtures of vegetable oil derived amides and esters  

SciTech Connect

Vegetable oils such as corn oil, peanut oil, and soy oil are reacted with polyamines to form a mixture containing amides, imides, half esters, and glycerol with subsequent treatment with a strong acid such as sulfonic acid to produce a product mix that has good detergent properties in fuels and lubricants.

Bonazza, B.R.; Devault, A.N.

1981-05-26

249

Amino acids and glycine ethyl ester as new crystallization reagents for lysozyme  

PubMed Central

Several amino acids and their derivatives are prominent additives in the field of protein chemistry. This study reports the use of charged amino acids and glycine ethyl ester as precipitants in protein crystallization, using hen egg-white lysozyme (HEWL) as a model. A discussion of the crystallization of HEWL using these reagents as precipitating agents is given.

Ito, Len; Shiraki, Kentaro; Yamaguchi, Hiroshi

2010-01-01

250

Partitioning of homologous nicotinic acid ester prodrugs (nicotinates) into dipalmitoylphosphatidylcholine (DPPC) membrane bilayers  

Microsoft Academic Search

The partitioning behavior of a series of perhydrocarbon nicotinic acid esters (nicotinates) between aqueous solution and dipalmitoylphosphatidylcholine (DPPC) membrane bilayers is investigated as a function of increasing alkyl chain length. The hydrocarbon nicotinates represent putative prodrugs, derivatives of the polar drug nicotinic acid, whose functionalization provides the hydrophobic character necessary for pulmonary delivery in a hydrophobic, fluorocarbon solvent, such as

Vivian Ojogun; Sandhya M. Vyas; Hans-Joachim Lehmler; Barbara L. Knutson

2010-01-01

251

21 CFR 178.3780 - Polyhydric alcohol esters of long chain monobasic acids.  

Code of Federal Regulations, 2010 CFR

...glycol or glycerol with long chain monobasic acids containing from...obtained by the ozonization of long chain alpha -olefins, the unreacted...75 percent by weight straight chain alpha -olefins and not more...locations.html. (2) Acid value 15-25 for each ester...

2010-01-01

252

Preanalytical Variables Affecting the Quantification of Fatty Acid Ethyl Esters in Plasma and Serum Samples  

Microsoft Academic Search

Background: Fatty acid ethyl esters (FAEEs) are cyto- toxic nonoxidative ethanol metabolites produced by esterification of fatty acids and ethanol. FAEEs are detectable in blood up to 24 h after ethanol consump- tion. The objective of this study was to assess the impact of gender, serum or plasma triglyceride concentration, time and temperature of specimen storage, type of alcoholic beverage

Britt L. Soderberg; Ewa T. Sicinska; Emily Blodget; Joanne E. Cluette-Brown; Paolo M. Suter; Theresa Schuppisser; Wilhem Vetter; Michael Laposata

253

Fatty Acid Ethyl Ester Synthesis in the Preparation of Scotch Whiskey  

Microsoft Academic Search

Fatty acid ethyl esters (FAEE), nonoxidative ethanol metabolites present in human organs commonly damaged by ethanol abuse, have been implicated as mediators of organ damage. FAEE are additives in various foods and beverages to provide flavor or fragrance, and therefore are common dietary lipid constituents. We hypothesized that FAEE could be generated during alcoholic beverage production because fatty acids are

Kendrick A Goss; Rami Alharethi; Michael Laposata

1999-01-01

254

Coriander Seed Oil Methyl Esters as Biodiesel Fuel: Unique Fatty Acid Composition and Excellent Oxidative Stability  

Technology Transfer Automated Retrieval System (TEKTRAN)

Coriander (Coriandrum sativum L.) seed oil methyl esters were prepared and evaluated as an alternative biodiesel fuel and contained an unusual fatty acid (FA) hitherto unreported as the principle component in biodiesel fuels: petroselinic (6Z-octadecenoic; 68.5 wt %) acid. Most of the remaining FA...

255

40 CFR 721.10457 - 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc., cyclohexanol, 2-ethyl-1-hexanol, fumaric acid and propylene glycol. 721.10457 ...721.10457 1,2-Benzenedicarboxylic acid, mixed esters with benzyl alc.,...

2013-07-01

256

Effects of some fatty acid esters on the viability and transplant- ability of ehrlich ascites tumor cells  

Microsoft Academic Search

SUMMARY Fatty acids, monoglycerides, and some esters of fatty acids show antitumor activity against Ehrlich ascites tumor in mice. For investigation of the in vivo mode of action of these lipids, the effects of those fatty acid esters on animal cells in vitro were studied in sheep red blood cells and Ehrlich ascites tumor cells. Throughout these studies, we used

Akiko Kato; Kunio Ando; G Tamura; K Arima

1971-01-01

257

Synthesis of fullerene amino acid derivatives by direct interaction of amino acid ester with C{sub 60}  

SciTech Connect

Refluxing C{sub 60} together with glycine ethyl ester yields C{sub 60}(Me{sub 2}CHNHCHCOOEt) (1) while under photochemical activation, the major product is C{sub 60}(EtOOCCHNHCCOOEt) (2b). Photochemical activation of C{sub 60} in the presence of sarcosine esters gives C{sub 60}(CH{sub 2}N(Me)CHCOOR) (3) C{sub 60}(ROOCCHNHCHCOOR) (2) (R = Me, Et, CH{sub 2}Ph). The esters do not hydrolyze easily in mineral acid containing solutions.

Liangbing Gan; Dejian Zhou; Chuping Luo [Peking Univ., Beijing (China)] [and others

1996-03-22

258

Evaluating the Silicic Acid Leakage Hypothesis in the Pacific Sector of the Southern Ocean  

NASA Astrophysics Data System (ADS)

The Silicic Acid Leakage Hypothesis (SALH; Matsumoto et al., 2002; Glob. Biogeochem. Cycles 16, 10.1029/2001GB001442) posits that lower atmospheric carbon dioxide concentrations during glacial times resulted from a net transfer of dissolved silicic acid from the Southern Ocean to the tropics, coupled with a corresponding shift in phytoplankton taxa in tropical waters toward a greater dominance by diatoms (relative to today). If valid, then the SALH requires that opal burial rates in the Southern Ocean were lower than today during the Last Glacial Maximum (LGM), while contemporary opal burial rates in tropical regions were greater than today. Previous studies in the Indian and Atlantic sectors of the Southern Ocean have shown little to no net change between the LGM and the Holocene when opal burial rates are integrated across Subantarctic and Antarctic zones. This study aims to test a sub-hypothesis suggested by Chase et al. (Deep-Sea Research-II, v.50, 2003, 799-832) that silicic acid was exported only out of the Pacific sector. Piston cores from the SW Pacific sector of the Southern Ocean were analyzed to determine opal burial fluxes. Magnetic susceptibility and Eucampia antarctica abundances were used to determine glacial cycles and identify cores containing both LGM and Holocene sediment. Fluxes of opal, calcium carbonate, and lithogenic material were evaluated by normalizing to 230Th to correct for sediment focusing. Our results show opal flux at, and to the south of, the Antarctic Polar Front (APF) to have been lower during the LGM compared to the Holocene, consistent with previous results from throughout the Southern Ocean. North of the APF, two cores show higher opal fluxes during the LGM. However, due to a possible hiatus in one of the cores, the degree to which opal flux during the LGM was greater than during the Holocene has a large uncertainty. Additional analyses are planned to help reduce this uncertainty.

Wall, A.; Baldwin, M.; Burckle, L.; Anderson, R.

2004-12-01

259

Acidbase properties of the crosslinked polysaccharidepolyimine layer deposited on the surface of siliceous material (acidbase properties of the polysaccharidepolyimine layer)  

Microsoft Academic Search

Siliceous materials with polymer layers formed by crosslinking of polysaccharidepolyimine mixtures have been evaluated in terms of their acidbase properties and surface charge densities. It was demonstrated that in the investigated pH region (2

Andrzej L. Dawidowicz; Dorota Wianowska; W?adys?aw Janusz

2003-01-01

260

Lewis acid catalysis of photochemical reactions. 5. Selective isomerization of conjugated butenoic and dienoic esters  

SciTech Connect

The effects of Lewis and Broensted acids upon the photoisomerization reactions of several conjugated butenoic and dienoic esters have been investigated. Lewis acids inhibit the photochemical deconjugation of ..cap alpha..,..beta..- to ..beta..,..gamma..-unsaturated butenoic esters and shift the photoequilibrium between E and Z isomers toward the Z isomer. As such, irradiation of E ..cap alpha..,..beta..-unsaturated esters in the presence of EtAlCl/sub 2/ provides a convenient method for the preparation of the thermodynamically less stable Z isomer. Irradiation of methyl (E,E)-2,4-hexadienoate and methyl (E,E)-5-phenyl-2,4-pentadienoate in the absence of added catalysts results in nonselective E,Z isomerization to give mixtures of all four stereoisomers in roughly comparable yields. In the presence of the Broensted acid trifluoroacetic acid, quantitative conversion of methyl 2,4-hexadienoates to methyl 3,4-hexadienoate is observed. The acid serves as a catalyst for the thermal 1,3-hydrogen shift of an allenic enol ester formed via a photochemical 1,5-hydrogen shift of the conjugated esters. Irradiation of the ground-state complexes of the conjugated esters with the Lewis acids EtAlCl/sub 2/ or BF/sub 3/ results in selective E,Z isomerization about the ..cap alpha..,..beta..-double bond in methyl 2,4-hexadienoate and the ..gamma..,delta-double bond in methyl 5-phenyl-24-pentadienoate. The mechanistic bases for the observed effects of Lewis acids are selective excitation of the more strongly absorbing E complex and more efficient isomerization of the excited E vs. Z complex.

Lewis, F.D.; Howard, D.K.; Barancyk, S.V.; Oxman, J.D.

1986-05-28

261

A new CO 2 disposal process via artificial weathering of calcium silicate accelerated by acetic acid  

Microsoft Academic Search

A new disposal process for anthropogenic CO2 via an artificially accelerated weathering reaction is proposed to counteract global warming. The process is essentially composed of the following two steps:(1)CaSiO3+2CH3COOH?Ca2++2CH3COO?+H2O+SiO2(2)Ca2++2CH3COO?+CO2+H2O?CaCO3?+2CH3COOHStep (1) is the extraction of calcium ions by acetic acid from calcium silicate, for example, wollastonite rocks. Step (2) is the deposition of calcium carbonate from the solution of calcium ions

M. Kakizawa; A. Yamasaki; Y. Yanagisawa

2001-01-01

262

21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...  

Code of Federal Regulations, 2013 CFR

... Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic acids). 573.637 Section 573.637 Food... Methyl esters of conjugated linoleic acid (cis-9, trans-11 and...

2013-04-01

263

21 CFR 573.637 - Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic...  

Code of Federal Regulations, 2010 CFR

...false Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10, cis-12-octadecadienoic acids). 573.637 Section...637 Methyl esters of conjugated linoleic acid (cis-9, trans-11 and trans-10,...

2009-04-01

264

Sucrose fatty acid sulphate esters as novel vaccine adjuvants: effect of the chemical composition.  

PubMed

Adjuvant activity of novel, synthetic sucrose derivatives towards a recombinant glycoprotein was determined in large, non-rodent animal species. Compared to antigen alone, up to 3000-fold higher virus neutralizing antibody titres (VNTs) and 10-fold higher cellular responses against classical swine fever virus were observed in pigs after two immunizations with the sucrose derivatives combined with a squalane-in-water emulsion. The chemical composition of the derivative was crucial and sucrose esters containing one sulphate and seven dodecanoic (C12) or decanoic (C10) esters exerted the highest adjuvanticity. Derivatives without sulphate, with fewer fatty acid esters or with shorter or longer alkyl esters were less effective. Strong adjuvant activity of these formulations was the result of synergistic collaboration between the sucrose ester and the squalane emulsion, as factor of increase in VNT by the individual components was between 4 and 34. Enhanced humoral and cell-mediated immune responses lasted for at least 24 weeks. We concluded that combinations of hydrophobic, negatively-charged sucrose fatty acid sulphate esters plus submicron emulsions of squalane-in-water are strong adjuvants for humoral and cell-mediated immunity and that these formulations are promising adjuvants for future vaccines containing poor immunogens. PMID:15542198

Blom, Anneke G; Hilgers, Luuk A Th

2004-12-21

265

Facile synthesis of acid-labile polymers with pendent ortho esters.  

PubMed

This work presents a facile approach for preparation of acid-labile and biocompatible polymers with pendent cyclic ortho esters, which is based on the efficient and mild reactions between cyclic ketene acetal (CKA) and hydroxyl groups. Three CKAs, 2-ethylidene-1,3-dioxane (EDO), 2-ethylidene-1,3-dioxolane (EDL), and 2-ethylidene-4- methyl-1,3-dioxolane (EMD) were prepared from the corresponding cyclic vinyl acetals by catalytic isomerization of the double bond. The reaction of CKAs with different alcohols and diols was examined using trace of p-toluenesulfonic acid as a catalyst. For the monohydroxyl alcohols, cyclic ortho esters were formed by simple addition of the hydroxyl group toward CKAs with ethanol showing a much greater reactivity than iso-propanol. When 1,2- or 1,3-diols were used to react with the CKAs, we observed the isomerized cyclic ortho esters besides the simple addition products. Biocompatible polyols, that is, poly(2-hydroxyethyl acrylate) (PHEA) and poly(vinyl alcohol) (PVA) were then modified with CKAs, and the degree of substitution of the pendent ortho esters can be easily tuned by changing feed ratio. Both the small molecule ortho esters and the CKA-modified polymers demonstrate the pH-dependent hydrolysis profiles, which depend also on the chemical structure of the ortho esters as well as the polymer hydrophobicity. PMID:22176024

Cheng, Jing; Ji, Ran; Gao, Shi-Juan; Du, Fu-Sheng; Li, Zi-Chen

2011-12-28

266

Comparison of phospholipid fatty acid (PLFA) and total soil fatty acid methyl esters (TSFAME) for characterizing soil microbial communities  

Microsoft Academic Search

Phospholipid fatty acid (PLFA) and total soil fatty acid methyl esters (TSFAME), both lipid-based approaches used to characterize microbial communities, were compared with respect to their reliable detection limits, extraction precision, and ability to differentiate agricultural soils. Two sets of soil samples, representing seven crop types from California's Central Valley, were extracted using PLFA and TSFAME procedures. PLFA analysis required

Rebecca E. Drenovsky; Geoff N. Elliott; Kenneth J. Graham; Kate M. Scow

2004-01-01

267

Synthesis of geranyl and citronellyl esters of coconut oil fatty acids through alcoholysis by Rhizomucor miehei lipase catalysis  

Microsoft Academic Search

Synthesis of geranyl and citronellyl esters of mixed fatty acids has been investigated by alcoholysis of coconut oil (CNO)\\u000a using Rhizomucor miehei lipase. CNO fatty acid esters of geraniol and citronellol have unique mild flavors that can be used in food materials. Both\\u000a geraniolysis and citronellolysis of CNO produce flavor esters in good yield. Depending on substrate concentration the molar

B. K. De; T. Chatterjee; D. K. Bhattacharyya

1999-01-01

268

Fumaric Acid Therapy in Psoriasis: A Double-Blind Comparison between Fumaric Acid Compound Therapy and Monotherapy with Dimethylfumaric Acid Ester  

Microsoft Academic Search

In a 4-month double-blind study the effects of dimethylfumaric acid esters (DMFAE-EC) and DMFAE plus salts of monoethylfumaric acid esters (fumaric acid combination, FAC-EC) in enteric-coated tablets were compared in 22 respectively 23 patients with psoriasis. In both groups about 50% showed a considerable improvement, i.e. the initial score was more than halved. The therapeutic effects showed no significant differences

C. Nieboer; D. de Hoop; P. N. J. Langendijk; A. C. van Loenen; J. Gubbels

1990-01-01

269

Stability studies on methyl and ethyl fatty acid esters of sunflower seed oil  

SciTech Connect

Fatty acid esters, high in linoleic acid, were prepared and stored for long-term engine tests. Storage tests were undertaken to obtain data on optimal storage requirements and general stability characteristics. Samples were kept at three temperature levels (20 C, 30C and fluctuating around 50 C) for a 90-day period and were removed at regular intervals for chemical and physical analysis. The influence of air, temperature, light, TBHQ and contact with mild steel was evaluated by comparing the free fatty acid, peroxide, anisidine, ultraviolet absorption, viscosity and inducation periods. A statistical model was used to evaluate the data and to reduce the data points to comparable curves. Storage of esters in contact with air, especially at a temperature above 30 C, resulted in significant increases in peroxide, ultraviolet absorption, free fatty acid, viscosity and anisidine values. Exclusion of air retarded oxidation at all temperature levels. A direct relationship between viscosity increases and oxidation parameters was evident. Exposure to light caused a small increase in the oxidation parameters of esters stored at the highest temperature level. Addition of TBHQ prevented oxidation of samples stored under moderate conditions. Under unfavorable storage conditions the anti-oxidant was no longer effective. Mild steel had very little effect on the oxidation parameters. The anisidine values of samples stored at the highest temperature level were slightly increased. Methyl esters performed slightly better than ethyl esters during the storage test. The recommended guidelines for storage of fatty acid ester fuels are: (1) airtight containers should be used, (2) the storage temperature should be less than 30 C, (3) mild steel (rust free) containers may be used, and (4) TBHQ has a beneficial effect on oxidation stability. 13 references.

Du Plessis, L.M.; De Villiers, J.B.M.; Van der Walt, W.H.

1985-04-01

270

Initial test of the silicic acid leakage hypothesis using sedimentary biomarkers  

NASA Astrophysics Data System (ADS)

Several mechanisms have been proposed for large CO2 changes at glacial Terminations, including shifting the CaCO3:Corg rain ratio by changing surface water nutrient supply, altering the balance between diatom and coccolithophore production. Diatom Si:N is highest in Fe-stressed high-latitude waters. Southern Ocean Fe enrichment studies suggest diatom Si demands reduced under Fe-replete (glacial) conditions, allowing increased silicic acid to leak northward in subducted intermediate water and upwell at lower latitudes. We test this `Silicic Acid Leakage' hypothesis using relative abundances of phytoplankton-specific biomarkers in Peru margin sediments spanning 0-20 Ka. Results indicate increased coccolithophorid:diatom production from ~0.5 to 3 between 18.0-15.5 Ka. Temporal correlation with the initial pCO2 rise and early deglacial shift in mode water ventilation implicates a coincidental, possibly causative reorganization of Sub-Antarctic Mode Water formation and reduced Fe abundance. However, coccolithophorid production subsequently declined, suggesting rain ratio changes were only partly responsible for the CO2 deglacial transition.

Higginson, Matthew J.; Altabet, Mark A.

2004-09-01

271

Synthesis, Stability and In Vitro Dermal Evaluation of Aminocarbonyloxymethyl Esters as Prodrugs of Carboxylic Acid Agents  

Microsoft Academic Search

Aminocarbonyloxymethyl esters 3 based on (S)-amino acid carriers were synthesised and evaluated as potential prodrugs of carboxylic acid agents. In addition, the compounds were evaluated as topical prodrugs with the aim of improving the dermal delivery of two non-steroidal anti-inflammatory agents: naproxen and flufenamic acid. The lipophilicities of these compounds were determined and their hydrolyses in aqueous solutions and in

Eduarda Mendes; Tnia Furtado; Joo Neres; Jim Iley; Tomi Jarvinen; Jarkko Rautio; Rui Moreira

2002-01-01

272

Comparative Subchronic Studies on 2,4-Dichlorophenoxyacetic Acid, Amine, and Ester in Rats  

Microsoft Academic Search

Forms of 2,4-dichlorophenoxyacetic acid (collectively known as 2,4-D) are herbicides used to control a wide variety of broadleaf and woody plants. Subchronic toxicity studies in rats were conducted on three forms of 2,4-D: the parent form, 2,4-D acid; 2,4-D dimethylamine salt (DMA); and 2,4-D 2-ethylhexyl ester (2-EHE). Doses in the subchronic studies (on an acid equivalent basis) were 0, 1,

Jeffrey M. Charles; Helen C. Cunny; Ronald D. Wilson; James S. Bus

1996-01-01

273

Synthesis of Dehydroabietic Acid (2-Acryloyloxy) Ethyl Ester in Ionic Liquids  

Microsoft Academic Search

A simple ionic liquid methodology for the synthesis of a novel derivative of dehydroabietic acid is described. 1-Butyl-3-methylimidazolium tetrafluoroborate [bmim]BF4, a typical ionic liquid, was used as an efficient and environmentally benign solvent in the synthesis of dehydroabietic acid (2-acryloloxy) ethyl ester by O-acylation reaction of dehydroabietic acid chloride with 2-hydroxyethyl acrylate. This new method showed the advantages of mild

Xuetang Xu; Wengui Duan; Qinghua Peng; Liumei Qin; Guanghua Li; Xiongmin Liu

2009-01-01

274

Discrimination among geometrical isomers of ? -linolenic acid methyl ester using low energy electron ionization mass spectrometry  

Microsoft Academic Search

There is a consensus that electron impact ionization mass spectrometry is not capable of discriminating among geometrical\\u000a isomers of unsaturated fatty acid methyl esters (and in general olefinic compounds). In this paper, we report the identification\\u000a of all eight geometrical isomers of ?-linolenic acid, one of the few essential ?-3 fatty acids that has attracted great attention, using low-energy electron

Leila Hejazi; Diako Ebrahimi; Michael Guilhaus; D. Brynn Hibbert

2009-01-01

275

Fatty acids and their sucrose esters affect the properties of fish skin gelatin-based film  

Microsoft Academic Search

The effects of fatty acids (FA) [palmitic acid (PA) and stearic acid (SA)] and their sucrose esters (FASE) on the mechanical\\u000a properties, water vapor permeability (WVP), light transmission, and color of films from bigeye snapper and brownstripe red\\u000a snapper skin gelatins were investigated. Tensile strength (TS) of films generally decreased with the addition of FA (ppp<0.05). However, films containing FASE

Akkasit Jongjareonrak; Soottawat Benjakul; Wonnop Visessanguan; Munehiko Tanaka

2006-01-01

276

Conjugated linoleic acid modulation of phorbol ester-induced events in murine keratinocytes  

Microsoft Academic Search

Recent work in our lab has shown that the chemoprotective fatty acid, conjugated linoleic acid (CLA), inhibits phorbol ester\\u000a skin tumor promotion in mice. Because little is known about the deposition of CLA into tissues as well as its biological activity,\\u000a this study compared the incorporation and biological activity of CLA to linoleic acid (LA; 18:2, c9, c12) and arachidonic

Kai-Li Liu; Martha A. Belury

1997-01-01

277

Benzoic acid glucosinolate esters and other glucosinolates from Arabidopsis thaliana.  

PubMed

The spectacular recent progress in Arabidopsis thaliana molecular genetics furnishes outstanding tools for studying the formation and function of all metabolites in this cruciferous species. One of the major groups of secondary metabolites in A. thaliana is the glucosinolates. These hydrophilic, sulfur-rich glycosides appear to serve as defenses against some generalist herbivores and pathogens, and as feeding and oviposition stimulants to specialist herbivores. To help study their biosynthesis and role in plant-insect interactions, we wanted to determine the complete glucosinolate content of A. thaliana. In previous studies, 24 glucosinolates had been identified from ecotype Columbia. We reinvestigated Columbia as well as additional ecotypes and mutant lines, and identified 12 further glucosinolates, including five novel compounds. Structures were elucidated by MS and NMR spectroscopy of their desulfated derivatives, and by enzymatic cleavage of the attached ester moieties. Four of the novel glucosinolates are benzoate esters isolated from the seeds. In all but one of these compounds, esterification is on the glucose moiety rather than the side chain, a very unusual feature for glucosinolates. Among additional glucosinolates identified were the first non-chain elongated, methionine-derived glucosinolate from A. thaliana and the first compounds that appear to be derived from leucine. PMID:11867099

Reichelt, Michael; Brown, Paul D; Schneider, Bernd; Oldham, Neil J; Stauber, Einar; Tokuhisa, Jim; Kliebenstein, Daniel J; Mitchell-Olds, Thomas; Gershenzon, Jonathan

2002-03-01

278

Enzymatic preparation of polyethylene glycol esters of castor oil fatty acids and their surface-active properties  

Microsoft Academic Search

This study concerns the preparation and evaluation of nonionic surfactants prepared from polyethylene glycol (PEG) esters\\u000a of castor oil fatty acid, a source of hydroxy fatty acid. A lipase-catalyzed esterification reaction has been employed to\\u000a prepare PEG esters of hydroxy acid to overcome problems associated with chemical processes. Castor oil fatty acid (85% ricinoleic\\u000a acid) was mixed with PEG of

M. Ghosh; D. K. Bhattacharyya

1998-01-01

279

Molecular Basis of Prodrug Activation by Human Valacyclovirase, an [alpha]-Amino Acid Ester Hydrolase  

SciTech Connect

Chemical modification to improve biopharmaceutical properties, especially oral absorption and bioavailability, is a common strategy employed by pharmaceutical chemists. The approach often employs a simple structural modification and utilizes ubiquitous endogenous esterases as activation enzymes, although such enzymes are often unidentified. This report describes the crystal structure and specificity of a novel activating enzyme for valacyclovir and valganciclovir. Our structural insights show that human valacyclovirase has a unique binding mode and specificity for amino acid esters. Biochemical data demonstrate that the enzyme hydrolyzes esters of {alpha}-amino acids exclusively and displays a broad specificity spectrum for the aminoacyl moiety similar to tricorn-interacting aminopeptidase F1. Crystal structures of the enzyme, two mechanistic mutants, and a complex with a product analogue, when combined with biochemical analysis, reveal the key determinants for substrate recognition; that is, a flexible and mostly hydrophobic acyl pocket, a localized negative electrostatic potential, a large open leaving group-accommodating groove, and a pivotal acidic residue, Asp-123, after the nucleophile Ser-122. This is the first time that a residue immediately after the nucleophile has been found to have its side chain directed into the substrate binding pocket and play an essential role in substrate discrimination in serine hydrolases. These results as well as a phylogenetic analysis establish that the enzyme functions as a specific {alpha}-amino acid ester hydrolase. Valacyclovirase is a valuable target for amino acid ester prodrug-based oral drug delivery enhancement strategies.

Lai, Longsheng; Xu, Zhaohui; Zhou, Jiahai; Lee, Kyung-Dall; Amidon, Gordon L. (Michigan)

2008-07-08

280

Comparison of three methods for the determination of sinapic acid ester content in enzymatically treated canola meals  

Microsoft Academic Search

The enzymatic reduction of sinapic acid ester content in canola meal using polyphenol oxidase from the fungus T. versicolor was investigated. To determine the effectiveness of this new process, the results obtained using two spectrophotometric methods and an HPLC analytical method for assaying sinapic acid ester content in the treated and untreated meals were compared. It was found that all

K. Lacki; Z. Duvnjak

1996-01-01

281

Comparison of three methods for the determination of sinapic acid ester content in enzymatically treated canola meals  

Microsoft Academic Search

The enzymatic reduction of sinapic acid ester content in canola meal using polyphenol oxidase from the fungusT. versicolor was investigated. To determine the effectiveness of this new process, the results obtained using two spectrophotometric methods and an HPLC analytical method for assaying sinapic acid ester content in the treated and untreated meals were compared. It was found that all the

K. Lacki; Z. Duvnjak

1996-01-01

282

Process for the generation of {alpha},{beta}-unsaturated carboxylic acids and esters using niobium catalyst  

SciTech Connect

A process using a niobium catalyst includes the step of reacting an ester or carboxylic acid with oxygen and an alcohol in the presence a niobium catalyst to respectively produce an {alpha},{beta}-unsaturated ester or carboxylic acid. Methanol may be used as the alcohol, and the ester or carboxylic acid may be passed over the niobium catalyst in a vapor stream containing oxygen and methanol. Alternatively, the process using a niobium catalyst may involve the step of reacting an ester and oxygen in the presence the niobium catalyst to produce an {alpha},{beta}-unsaturated carboxylic acid. In this case the ester may be a methyl ester. In either case, niobium oxide may be used as the niobium catalyst with the niobium oxide being present on a support. The support may be an oxide selected from the group consisting of silicon oxide, aluminum oxide, titanium oxide and mixtures thereof. The catalyst may be formed by reacting niobium fluoride with the oxide serving as the support. The niobium catalyst may contain elemental niobium within the range of 1 wt % to 70 wt %, and more preferably within the range of 10 wt % to 30 wt %. The process may be operated at a temperature from 150 to 450 C and preferably from 250 to 350 C. The process may be operated at a pressure from 0.1 to 15 atm. absolute and preferably from 0.5--5 atm. absolute. The flow rate of reactants may be from 10 to 10,000 liter/kg catalyst/h, and preferably from 100 to 1,000 liter/kg catalyst/h.

Gogate, M.R.; Spivey, J.J.; Zoeller, J.R.

1999-12-07

283

21 CFR 172.854 - Polyglycerol esters of fatty acids.  

Code of Federal Regulations, 2013 CFR

...safflower oil, sesame oil, soybean oil, and tallow and the...from these substances (hydrogenated and nonhydrogenated...acid derived from tall oil fatty acids meeting the...a cloud inhibitor in vegetable and salad oils...

2013-04-01

284

Fatty acid esters of monochloropropanediol (MCPD) and glycidol in refined edible oils.  

PubMed

Recently, fatty acid esters of monochloropropanediol (MCPD) and that of glycidol have been reported in refined edible oils. Since then a wealth of research has been published on the factors influencing the formation of these contaminants in foods. It can be noted that the predominant precursors in a given matrix will not necessarily be the same as in other matrices. Further, proven relationships in the past between precursors responsible for free MCPD or free glycidol formation will not necessarily be valid for their fatty acid-esterified counterparts. This review attempts to summarise the current status of the literature as it pertains to the reasons surrounding the manifestation of MCPD esters and glycidyl esters in oils and fats. Recent efforts to mitigate the levels of these contaminants were highlighted and put into the context of their respective reaction matrices. As more accurate occurrence data for MCPD esters and glycidyl esters in other foods are collected, more targeted mitigation experiments can be formulated with respect to the reaction matrices under investigation. PMID:23020600

Craft, B D; Chiodini, A; Garst, J; Granvogl, M

2012-09-28

285

Synthesis and evaluation of odour-active methionyl esters of fatty acids via esterification and transesterification of butter oil.  

PubMed

Methionol-derived fatty acid esters were synthesised by both chemical and lipase catalysed esterification between fatty acids and methionol. Beneficial effects of both methods were compared qualitatively and quantitatively by GC-MS/GC-FID results. And the high acid and heat stability of our designed methionyl esters meet the requirement of the food industry. Most importantly, the sensory test showed that fatty acid carbon-chain length had an important effect on the flavour attributes of methionyl esters. Moreover, through Lipozyme TL IM-mediated transesterification, valuable methionol-derived esters were synthesised from the readily available natural material butter oil as the fatty acid source. The conversion of methionol and yield of each methionyl ester were also elucidated by GC-MS-FID. PMID:24128547

Li, Cheng; Sun, Jingcan; Fu, Caili; Yu, Bin; Liu, Shao Quan; Li, Tianhu; Huang, Dejian

2013-09-07

286

The rates of oxidation of unsaturated fatty acids and esters  

Microsoft Academic Search

SummaryThe rates of autoxidation of oleic acid, ethyl oleate, linoleic acid, 10,12-linoleic acid, ethyl linoleate, trilinolein, pentaerythritol\\u000a linoleate, dipentaerythritol linoleate, elaidolinolenic acid, linolenic acid, ethyl linolenate, trilinolenin, and methyl arachidonate\\u000a have been studied by oxygen uptake in a Warburg respirometer and the results are compared with the rates of enzymatic oxidation\\u000a of lipoxidase substrates.\\u000a \\u000a The increase in the number of

Ralph T. Holman; Otto C. Elmer

1947-01-01

287

Catalytic synthesis of fatty acid methyl esters from extremely low quality greases  

Technology Transfer Automated Retrieval System (TEKTRAN)

Biodiesel (BD) is a renewable fuel for compression ignition engines that is composed of the simple alkyl esters, usually methyl-, of fatty acids (FAME). It is typically produced via base-catalyzed transesterification between refined vegetable oil or animal fat (e.g., soybean oil, tallow) and an alc...

288

Nonenzymic browning. 3. Browning reactions during heating of fish oil fatty acid esters with protein  

Microsoft Academic Search

Summary During heating of mixtures of methyl esters of polyunsaturated fish oil fatty acids and albumen under simulated conditions of roasting and frying of fish, peroxides present in the lipidic fraction are rapidly decomposed and form both liposoluble and insoluble brown pigments with free amino groups of albumen. Small amounts of lipids in the mixture have already great effect on

J. Pokorn; B. A. El-Zeany; G. Jan?ek

1973-01-01

289

Novel and Efficient One-Pot Synthesis of (Aminophenyl)carbamic Acid Esters  

Microsoft Academic Search

A novel and efficient protocol is developed for the synthesis of various (aminophenyl)carbamic acid esters from the reduction and condensation of nitrophenyl isocyanate derivatives. The reaction takes place in various hydroxy derivatives such as alcohols or phenols under a hydrogen atmosphere using Raney nickel as catalyst. Products are obtained by a convenient onepot synthesis with excellent yields and short reaction

Antonio Garofalo; Laurence Goossens; Perrine Six; Nicolas Lebegue; Patrick Depreux

2011-01-01

290

PRODUCTION OF FATTY ACID ESTERS BY DIRECT ALKALINE TRANSESTERIFICATION: PROCESS OPTIMIZATION FOR IMPROVED ECONOMICS  

Technology Transfer Automated Retrieval System (TEKTRAN)

We have recently described a new method for the production of fatty acid esters, for use as biodiesel, from the triacylglycerols residing in oilseeds. This method involves incubation of the oilseeds themselves in alkaline alcohol solutions at ambient temperature and pressure, using the same reagent...

291

Synthesis and application of chiral triazine condensing reagents prepared from esters of amino acids.  

PubMed

Treatment of cyanuric chloride with chiral amines or esters of chiral amino acids gave chiral 2,4-dichloro-6-alkylamino-1,3,5-triazines (2-5) in 49-69% yield, which were found useful as coupling reagents. Enantioselective activation and enantioselective aminolysis in the presence of 2-5 was observed. PMID:11995981

Kami?ski, Z J; Zajac, K J; Jastrzabek, K

2001-01-01

292

Contamination of vegetable oils marketed in Italy by phthalic acid esters  

Microsoft Academic Search

More than 90% of the phthalic acid esters (PAEs) produced in Europe is used to plasticize polyvinyl chloride (PVC). Animal studies have shown that some PAEs can damage the liver and interfere with the endocrine system, whereas data on the toxic effects on humans are inconsistent. For the general population, the diet is believed to be the main source of

Natalia Nanni; Katell Fiselier; Koni Grob; Mauro Di Pasquale; Laura Fabrizi; Paolo Aureli; Ettore Coni

2011-01-01

293

Enantioselective hydrogenation of isophorone over Pd catalysts in the presence of(?)-dihydroapovincaminic acid ethyl ester  

Microsoft Academic Search

The enantioselective heterogeneous catalytic hydrogenation of isophorone in the presence of apovincaminic acid ethyl ester was investigated. Various Pd black catalysts differing in their preparation method were studied. The catalysts were characterized by different methods such as physical adsorption and chemisorption, SEM and XPS. An explanation was created for the different enantioselectivity of the catalysts being precipitated by different reducing

G Farkas; S??pos; A Tungler; A Srkny; J. L Figueiredo

2001-01-01

294

Clerodane diterpenoids, long chain esters of coumaric acid and other compounds from Baccharis myrsinites  

Microsoft Academic Search

A new clerodane diterpenoid and two new long chain esters of trans- and cis-coumaric acid, in addition to known triterpenoids and one known clerodane diterpenoid, have been isolated and characterized from Baccharis myrsinites. The structures were determined by spectroscopic techniques.

Cong-Jun Li; Ahmed A. Ahmed; Alicia Del Carmen Arias; Tom J. Mabry

1997-01-01

295

Chemically Modified Fatty Acid Methyl Esters: Potential as Lubricant and Surfactant  

Technology Transfer Automated Retrieval System (TEKTRAN)

Renewable raw materials are going to play a noteworthy role in the development of sustainable green chemistry because of their eco-friendly and non-toxic nature. A novel process was developed for the production of biodegradable lubricant base stocks from epoxidized fatty acid methyl esters and comm...

296

40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.  

Code of Federal Regulations, 2013 CFR

(1) The chemical substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section. (2) The significant new uses...

2013-07-01

297

40 CFR 721.1728 - Benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester.  

Code of Federal Regulations, 2010 CFR

(1) The chemical substance identified as benzoic acid, 2-(3-phenylbutylidene)amino-, methyl ester (PMN P-85-1211) is subject to reporting under this section for the significant new uses described in paragraph (a)(2) of this section. (2) The significant new uses...

2010-07-01

298

How can temperature affect reverse micellar extraction using sucrose fatty acid ester?  

Microsoft Academic Search

The reverse micellar extraction of lysozyme using sucrose fatty acid ester was found to be greatly affected by the temperature in the extraction process. For example, lysozyme was perfectly extracted from the feed aqueous phase to the reverse micellar organic phase at 25C, while it was not extracted at 5C at all. After entrapping lysozyme into the reverse micelles, lysozyme

Hidetaka Noritomi; Naoki Kojima; Satoru Kato; Kunio Nagahama

2006-01-01

299

Immunomodulatory effect of caffeic acid phenethyl ester in Balb\\/c mice  

Microsoft Academic Search

Caffeic acid phenethyl ester (CAPE), an the active component of propolis, is known to have anticarcinogenic, antiviral and various biological activities; however, the effect of CAPE on the immunomodulatory activity in vivo remains unknown. We have investigated the effect of CAPE on the immune system in female Balb\\/c mice. CAPE (0, 5, 10, 20 mg\\/kg) was given to mice orally

Jae Hyun Park; Jong Kwon Lee; Hyung Soo Kim; Seung Tae Chung; Juno H. Eom; Kyung A. Kim; Se Jin Chung; Soon Young Paik; Hye Young Oh

2004-01-01

300

Lewis acid catalysis of photochemical reactions. 7. Photodimerization and cross-cycloaddition of cinnamic esters  

SciTech Connect

The effects of Lewis acid complexation upon the molecular structure, solid-state photodimerization, and solution dimerization and cross-cycloaddition of cinnamic esters have been investigated. Comparison of crystal structures for free and SnCl/sub 4/-complexed ethyl cinnamate indicates that the enone double bonds are lengthened, the single bonds are shortened, and the enone conformation changes from s-cis to s-trans upon complexation. These changes are consistent with calculated changes in ..pi.. bonding and net charges. Solid-state photodimerization of free and complexed cinnamic esters and related molecules yield syn head-to-tail (..cap alpha..-truxillate) dimers. In most cases the Lewis acid complexes dimerize more efficiently and stereoselectively than the free esters. Photodimerization and cross-cycloaddition of methyl cinnamate in dilute solution is also catalyzed by Lewis acids. The mechanism of these reactions involves electronic excitation of a ground-state ester (dimerization) or simple olefin (cross cycloaddition). The catalytic effect of Lewis acids is attributed to an increase in excited-state lifetime and reactivity.

Lewis, F.D.; Quillen, S.L.; Hale, P.D.; Oxman, J.D.

1988-02-17

301

Oxidative transformation of a naturally occurring okadaic acid diol ester by the diatom Thalassiosira weissflogii  

Microsoft Academic Search

The diarrhetic shellfish poisoning (DSP) toxin okadaic acid (1) is found in extracts of the dinoflagellate Prorocentrum lima together with a suite of diol esters such as 2. When 2 was added to the culture medium of the centric diatom Thalassiosira weissflogii, it was transformed into a range of products within three days. Three of these products, 3, 4 and

Tingmo Hu; Ian Burton; Jonathan M. Curtis; Michael A. Quilliam; John A. Walter; Anthony J. Windust; Jeffrey L. C. Wright

1999-01-01

302

Fumaric acid and its esters: An emerging treatment for multiple sclerosis with antioxidative mechanism of action  

Microsoft Academic Search

Fumaric acid was originally therapeutically used in psoriasis. Several lines of evidence have demonstrated immunomodulatory but also neuroprotective effects for FAE. Clinical studies in psoriasis showed a reduction of peripheral CD4+ and CD8+ T-lymphocytes due to the ability of FAE to induce apoptosis. In vitro studies with the ester dimethylfumarate (DMF) described an inhibitory effect on nuclear factor kappa B

R. Gold; R. A. Linker; M. Stangel

303

Final Safety Assessment of Thiodipropionic Acid and Its Dialkyl Esters as Used in Cosmetics  

Microsoft Academic Search

Dilauryl thiodipropionate (DLTDP), dicetyl thiodipropionate, dimyristyl thiodipropionate, distearyl thiodipropionate, and ditridecyl thiodipropionate are dialkyl esters of their respective alcohols and thiodipropionic acid (TDPA) used in cosmetics. Ingested DLTDP was excreted in the urine as TDPA. Single-dose acute oral and parenteral studies and subchronic and chronic repeated dose oral studies did not suggest significant toxicity. Neither DLTDP nor TDPA was irritating

Catherine Diamante; Monice Zondlo Fiume; Wilma F. Bergfeld; Donald V. Belsito; Ronald A. Hill; Curtis D. Klaassen; Daniel C. Liebler; James G. Marks; Ronald C. Shank; Thomas J. Slaga; Paul W. Snyder; F. Alan Andersen

2010-01-01

304

Lack of spermatotoxic effects of methyl and ethyl esters of p-hydroxybenzoic acid in rats  

Microsoft Academic Search

Parabens are alkyl esters of p-hydroxybenzoic acid widely used as preservatives in foodstuffs, cosmetics toiletries and pharmaceuticals. These compounds are known to exert a weak estrogenic activity in estrogen receptor assays in vitro. In addition butyl and propyl parabens show uterotrophic activity in vivo. It was previously shown that exposure of post-weaning rats and mice to butyl or propyl parabens

Shinshi Oishi

2004-01-01

305

Antimicrobial activity of fatty acid methyl esters of some members of Chenopodiaceae.  

PubMed

Fatty acid methyl ester (FAME) extracts of four halophytic plants, viz. Arthrocnemum indicum, Salicornia brachiata, Suaeda maritima and Suaeda monoica belonging to the family Chenopodiaceae, were prepared and their composition was analyzed by GC-MS. The FAME extracts were also screened for antibacterial and antifungal activities. The GC-MS analysis revealed the presence of more saturated fatty acids than unsaturated fatty acids. Among the fatty acids analyzed, the relative percentage of lauric acid was high in S. brachiata (61.85%). The FAME extract of S. brachiata showed the highest antibacterial and antifungal activities among the extracts tested. The other three extracts showed potent antibacterial and moderate anticandidal activities. PMID:18669016

Chandrasekaran, Manivachagam; Kannathasan, Krishnan; Venkatesalu, Venugopalan

306

Isolation of natural arachidonic acid as its methyl ester  

Microsoft Academic Search

SummaryFresh beef suprarenal glands were ground and extracted thoroughly with alcohol and then with ethyl ether. After removal of\\u000a solvent the total lipid residue was saponified, and the fatty acids were recovered by extraction. The less unsaturated acids\\u000a were removed by crystallization from acetone at ?40C. At this stage the filtrate contained essentially all the arachidonic\\u000a acid originally present in

S. F. Herb; R. W. Riemenschneider; Jeanette Donaldson

1951-01-01

307

Structure-activity relationship investigation of bis(2-chloroethyl)aminoethyl esters of some carboxylic acids.  

PubMed

A study of quantitative structure-activity relationships (QSAR) in a series of carboxylic acid bis(2-chloroethyl)aminoethyl esters with potential antitumor activity was carried out. The statistical-heuristic technique was applied to estimate the contributions of the structural features of the compounds to the probability of their activity in vivo against lymphoid leukemia L1210. The results obtained were compared with those of the pharmacological screening of the esters. Some assumptions are made concerning the difference in antileukemic activity of compounds based on the computed weights of their structural features. PMID:2395899

Pajeva, I; Manolov, I; Golovinsky, E V

1990-05-01

308

Occurrence of 3-chloropropane-1,2-diol fatty acid esters in infant and baby foods  

Microsoft Academic Search

A series of fourteen starter formula, follow-up formula, and growing-up milk produced by three manufacturers was analyzed\\u000a by for the chloropropanols 1,3-dichloropropan-2-ol (1,3-DCP), 3-chloropropane-1,2-diol (3-MCPD) and their fatty acid esters.\\u000a While none of the products contained free chloropropanols at levels exceeding the method detections limits, all of them contained\\u000a relatively high amounts of 3-MCPD esters. The latter concentrations ranged from

Zuzana Zelinkov; Marek Doleal; Jan Velek

2009-01-01

309

Branched chain amino acid metabolism in the biosynthesis of Lycopersicon pennellii glucose esters  

Microsoft Academic Search

Lycopersicon pennellii Corr. (D'Arcy) an insect-resistant, wild tomato possesses high densities of glandular trichomes which exude a mixture of 2,3,4-tri-O-acylated glucose esters that function as a physical impediment and feeding deterrent to small arthropod pests. The acyl moieties are branched C and C acids, and branched and straight chain C, C, and C acids. The structure of the branched acyl

D. S. Walters; J. C. Steffens

1990-01-01

310

Lowered ?3 polyunsaturated fatty acids in serum phospholipids and cholesteryl esters of depressed patients  

Microsoft Academic Search

Depression is associated with a lowered degree of esterification of serum cholesterol, an increased C20:4?6\\/C20:5?3 ratio and decreases in ?3 fractions in fatty acids (FAs) or in the red blood cell membrane. The aims of the present study were to examine: (i) serum phospholipid and cholesteryl ester compositions of individual saturated fatty acids (SFAs), monounsaturated FAs (MUFAs) and polyunsaturated FAs

Michael Maes; Armand Christophe; Joris Delanghe; Carlo Altamura; Hugo Neels; Herbert Y Meltzer

1999-01-01

311

Improved separation of conjugated fatty acid methyl esters by silver ion-high-performance liquid chromatography  

Microsoft Academic Search

Operating from one to six silver ion-high-performance liquid chromatography (Ag+-HPLC) columns in series progressively improved the resolution of the methyl esters of conjugated linoleic acid (CLA) isomeric\\u000a mixtures from natural and commercial products. In natural products, the 8 trans, 10 cis-octadecadienoic (18?2) acid was resolved from the more abundant 7 trans, 9 cis-18?2, and the 10 trans, 12 cis-18?2 was

Najibullah Sehat; Rainer Rickert; Magdi M. Mossoba; John K. G. Kramer; Martin P. Yurawecz; John A. G. Roach; Richard O. Adlof; Kim M. Morehouse; Jan Fritsche; Klaus D. Eulitz; Hans Steinhart; Yuoh Ku

1999-01-01

312

Direct-blackening photographic materials based on cellulose esters and phosphomolybdic acid  

Microsoft Academic Search

The authors have examined the scope for making photographic materials by forming phosphomolybdic structures with cellulose ester groups. The material was made by esterifying cellulose in a melt composed of urea and polyphosphoric acid at 160-170°C, with the molybdenum subsequently introduced by sorption from acid (NH)MoO solution under static conditions with periodic stirring. Potentiometric titration showed that phosphomolybdate structures are

N. K. Luneva; V. V. Komar; A. G. Oputina; I. N. Ermolenko

1988-01-01

313

The enzymatic hydrolysis and tissue oxidation of fatty acid esters of sucrose  

Microsoft Academic Search

SummaryVarious preparations of sucrose fatty acid esters were hydrolyzed by wheat germ or pancreatic lipase, pancreatin, pancreatic\\u000a juice, ?-amylase, invertase, or liver homogenates to yield sucrose and free fatty acids as products. The greatest activity\\u000a was observed with the liver homogenate.\\u000a \\u000a None of the enzymes studied cleaved the glycosidic linkage as indicated by the lack of appearance of reducing groups

James F. Berry; David A. Turner

1960-01-01

314

Synergist effect of sucrose fatty acid esters on nisin inhibition of gram-positive bacteria.  

PubMed

Nisin in combination with the sucrose fatty acid esters, sucrose palmitate (P-1570 and P-1670) or sucrose stearate (S-1570 and S-1670) was tested against a range of Gram-negative and Gram-positive bacteria. Initial liquid culture investigation showed that the sugar ester P-1670 resulted in a synergist enhancement of the bacteriostatic activity of nisin against Gram-positive bacteria and not Gram-negative bacteria. Some enhancement of the bactericidal activity of nisin against Listeria monocytogenes was also observed. This increased nisin inhibitory effect was confirmed on solid media using plates with gradients of pH and NaCl. Synergism was observed with all four sucrose fatty acid esters, which enhanced the antimicrobial activity of nisin against several strains of L. monocytogenes, Bacillus cereus (both cells and spores), Lactobacillus plantarum and Staphylococcus aureus. The combination of nisin and the sucrose fatty acid esters showed no inhibition of Gram-negative bacteria (Salmonella enteritidis, Salm. typhimurium and Pseudomonas aeruginosa). PMID:9871322

Thomas, L V; Davies, E A; Delves-Broughton, J; Wimpenny, J W

1998-12-01

315

Secreted 3-isopropylmalate methyl ester signals invasive growth during amino acid starvation in Saccharomyces cerevisiae.  

PubMed

The Saccharomyces cerevisiae methyltransferase encoded by TMT1 catalyzes the AdoMet-dependent monomethylation of 3-isopropylmalate, an intermediate of the leucine biosynthetic pathway. The biological significance of methylating 3-isopropylmalate and the relationship between Tmt1 and the leucine biosynthetic pathway is not yet established. We present evidence here showing that methylation of 3-isopropylmalate functions to extracellularly signal yeast to grow invasively. We show that methyl esterification generates 3-isopropylmalate-1-methyl ester. We find that the Tmt1 methyltransferase functions independently of the biosynthetic pathway but is induced when cells are starved for amino acids; the largest induction is observed with the removal of leucine from the media. This amino acid starvation stress response is controlled by the transcriptional activator Gcn4. After methylation, 3-isopropylmalate methyl ester is secreted into the media within 3 h. Thin layer chromatography and gas chromatography mass spectroscopy confirm that the intact molecule is secreted. Finally, we show that purified 3-isopropylmalate methyl ester can enhance the ability of the haploid yeast strain 10560-23C to grow invasively. Our data identifies 3-isopropylmalate methyl ester as an autoinductive molecule that provides a signal to yeast to switch from vegetative to invasive growth in response to amino acid starvation. PMID:18092814

Dumlao, Darren S; Hertz, Nicholas; Clarke, Steven

2007-12-20

316

Sinapic acid ester metabolism in wild type and a sinapoylglucose-accumulating mutant of arabidopsis.  

PubMed

Sinapoylmalate is one of the major phenylpropanoid metabolites that is accumulated in the vegetative tissue of Arabidopsis thaliana. A thin-layer chromatography-based mutant screen identified two allelic mutant lines that accumulated sinapoylglucose in their leaves in place of sinapoylmalate. Both mutations were found to be recessive and segregated as single Mendelian genes. These mutants define a new locus called SNG1 for sinapoylglucose accumulator. Plants that are homozygous for the sng1 mutation accumulate normal levels of malate in their leaves but lack detectable levels of the final enzyme in sinapate ester biosynthesis, sinapoylglucose:malate sinapoyltransferase. A study of wild-type and sng1 seedlings found that sinapic acid ester biosynthesis in Arabidopsis is developmentally regulated and that the accumulation of sinapate esters is delayed in sng1 mutant seedlings. PMID:8972602

Lorenzen, M; Racicot, V; Strack, D; Chapple, C

1996-12-01

317

Toxicological assessment of 3-chloropropane-1,2-diol and glycidol fatty acid esters in food.  

PubMed

Fatty acid esters of 3-chloropropane-1,2-diol (3-MCPD) and glycidol are a newly identified class of food process contaminants. They are widespread in refined vegetable oils and fats and have been detected in vegetable fat-containing products, including infant formulas. There are no toxicological data available yet on the 3-MCPD and glycidol esters, and the primary toxicological concern is based on the potential release of 3-MCPD or glycidol from the parent esters by lipase-catalyzed hydrolysis in the gastrointestinal tract. Although 3-MCPD is assessed as a nongenotoxic carcinogen with a tolerable daily intake (TDI) of 2??g/kg body weight (bw), glycidol is a known genotoxic carcinogen, which induces tumors in numerous organs of rodents. The initial exposure estimates, conducted by Federal Institute for Risk Assessment (BfR) under the assumption that 100% of the 3-MPCD and glycidol are released from their esters, revealed especially that infants being fed commercial infant formula could ingest harmful amounts of 3-MCPD and glycidol. However, the real oral bioavailability may be lower. As this gives rise for toxicological concern, the currently available toxicological data of 3-MCPD and glycidol and their esters are summarized in this review and discussed with regard to data gaps and further research needs. PMID:21351250

Bakhiya, Nadiya; Abraham, Klaus; Grtler, Rainer; Appel, Klaus Erich; Lampen, Alfonso

2011-02-23

318

40 CFR 721.5375 - Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis-[[[[(sub-sti-tut-ed)] amino]-alkyl-phenyl...  

Code of Federal Regulations, 2013 CFR

...2013-07-01 false Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis...721.5375 Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis...chemical substance ni-tro-thio-phene-car-boxy-lic acid, ethyl ester,...

2013-07-01

319

Evidence of silicic acid leakage to the tropical Atlantic via Antarctic Intermediate Water during Marine Isotope Stage 4  

NASA Astrophysics Data System (ADS)

Antarctic Intermediate Water (AAIW) and Subantarctic Mode Water (SAMW) are the main conduits for the supply of dissolved silicon (silicic acid) from the deep Southern Ocean (SO) to the low-latitude surface ocean and therefore have an important control on low-latitude diatom productivity. Enhanced supply of silicic acid by AAIW (and SAMW) during glacial periods may have enabled tropical diatoms to outcompete carbonate-producing phytoplankton, decreasing the relative export of inorganic to organic carbon to the deep ocean and lowering atmospheric pCO2. This mechanism is known as the "silicic acid leakage hypothesis" (SALH). Here we present records of neodymium and silicon isotopes from the western tropical Atlantic that provide the first direct evidence of increased silicic acid leakage from the Southern Ocean to the tropical Atlantic within AAIW during glacial Marine Isotope Stage 4 (~60-70 ka). This leakage was approximately coeval with enhanced diatom export in the NW Atlantic and across the eastern equatorial Atlantic and provides support for the SALH as a contributor to CO2 drawdown during full glacial development.

Griffiths, James D.; Barker, Stephen; Hendry, Katharine R.; Thornalley, David J. R.; Flierdt, Tina; Hall, Ian R.; Anderson, Robert F.

2013-06-01

320

Effect of Quartz/Mullite Blend Ceramic Additive on Improving Resistance to Acid of Sodium Silicate-Activated Slag Cement.  

National Technical Information Service (NTIS)

We evaluated the usefulness of manufactured quartz/mullite blend (MQMB) ceramic powder in increasing the resistance to acid of sodium silicate-activated slag (SSAS) cementitious material for geothermal wells. A 15-day exposure to 90 deg CO2-laden H2SO4 re...

L. E. Brothers T. Sugama T. R. Van de Putte

2005-01-01

321

Antioxidant properties of the fatty alcohol esters of gallic acid  

Microsoft Academic Search

Summary and ConclusionsThe antioxidant properties of octyl, dodecyl, tetradecyl, hexadecyl, and octadecyl gallates in lard substrate were determined\\u000a by the active oxygen method. The order of their effectiveness was about the same as that of the more active antioxidants,\\u000a nordihydroguariaretic acid and gallic acid, that have been reported. The carry-over of the antioxidant properties into baked\\u000a goods was determined by

Steward G. Morris; Lillian A. Kraekel; Dorothy Hammer; J. S. Myers; R. W. Riemenschneider

1947-01-01

322

Hydroxycinnamic acid ethyl esters as precursors to ethylphenols in wine.  

PubMed

A method for determining ethyl coumarate and ethyl ferulate in wine using GC-MS with deuterium-labeled analogues has been developed and used to measure the evolution of these two esters during the production of two commercial monovarietal red wines, cv. Grenache and Shiraz. During fermentation, the concentration of ethyl coumarate rose from low levels to 0.4 mg/L in Grenache and 1.6 mg/L in Shiraz wines. These concentrations then increased further during barrel aging to 1.4 and 3.6 mg/L, respectively. The concentration of ethyl ferulate was much lower, reaching a maximum of only 0.09 mg/L. Conversion of ethyl coumarate and ethyl ferulate to their corresponding ethylphenols was observed during fermentations of a synthetic medium with two strains of Dekkera bruxellensis (AWRI 1499 and AWRI 1608), while a third (strain AWRI 1613) produced no ethylphenols at all from these precursors. Strains AWRI 1499 and 1608 produced 4-ethylphenol from ethyl coumarate in 68% and 57% yields, respectively. The corresponding yields of 4-ethylguaiacol from ethyl ferulate were much lower, 7% and 3%. Monitoring of ethyl coumarate and ethyl ferulate concentration during the Dekkera fermentations showed that the selectivity for ethylphenol production according to yeast strain and the precursor was principally a result of variation in esterase activity. Consequently, ethyl coumarate can be considered to be a significant precursor to 4-ethylphenol in wines affected by these two strains of Brettanomyces/Dekkera yeast, while ethyl ferulate is not an important precursor to 4-ethylguaiacol. PMID:22324721

Hixson, Josh L; Sleep, Nicola R; Capone, Dimitra L; Elsey, Gordon M; Curtin, Christopher D; Sefton, Mark A; Taylor, Dennis K

2012-02-23

323

Synthesis of All Distinct ?-Methyl-Substituted Isomers of Amino Bis(2,2?-Ethanoic Acid) Diethyl Ester and Ethylene Diamine Tetraacetic Acid Tetraethyl Ester Scaffolds  

Microsoft Academic Search

The syntheses of three dialkylated and six tetraalkylated ethylene diamine tetraacetic acid tetraesters is described. The dialkylated derivatives were synthesized by a convergent non-racemizing route to yield three enantiomerically and diastereomerically pure tetraesters (SS)-3a, (RR)-3b and (R?S?)-3c in 5557% yields from alanine ethyl ester 1. Enantiomerically and diastereomerically pure tetraalkylated derivatives (SSSS)-8a, (RRRR)-8b, (2R?,2?S?,2?R?,2?S?)-8c, (2R?,2?R?,2?S?,2?S?)-8d, (2R,2?R,2?R,2?S)-8e and (2S,2?S,2?S,2?R)-8f were synthesized

Shabana S Insaf; Donald T Witiak

2000-01-01

324

[Determination of three active ingredients in food additive sucrose fatty acid ester by TLC scanning].  

PubMed

A method of separation and quantitation of monoester, diester and triester in food additive sucrose fatty acid esters by TLC with dual-wavelength TLC scanner in the sawtooth scanning mode is described. The detective wavelength was 530 nm and the reference wavelength was 700 nm. A mixture of chloroform, methanol, acetic acid and water (80:10:8:1, V/V) was used as mobile phase. The calibration curve was linear over a range from 4 micrograms to 60 micrograms with correlation coefficients of 0.9949-0.9980. The average recoveries were 96.45%-98.73% (n = 3, RSD = 2.7%-3.2%). This method is accurate, simple and dependable, with a wide range of linearity. It has been applied to the analysis of various samples and can be used for the quality control of the food additive sucrose fatty acid ester. PMID:12541521

Xie, X T; Zhang, H P; Zheng, P; Luo, C Y

2000-07-01

325

Water chemical ionization mass spectrometry of aldehydes, ketones esters, and carboxylic acids  

SciTech Connect

Chemical ionization mass spectrometry (CI) of aliphatic and aromatic carbonyl compounds using water as the reagent gas provides intense pseudomolecular ions and class-specific fragmentation patterns that can be used to identify aliphatic aldehydes, ketones, carboxylic acids, and esters. The length of ester acyl and alkyl groups can easily be determined on the basis of loss of alcohols from the protonated parent. Water CI provides for an approximately 200:1 selectivity of carbonyl species over alkanes. No reagent ions are detected above 55 amu, allowing species as small as acetone, propanal, acetic acid, and methyl formate to be identified. When deuterate water was used as the reagent, only the carboxylic acids and ..beta..-diketones showed significant H/D exchange. The use of water CI to identify carbonyl compounds in a wastewater from the supercritical water extraction of lignite coal, in lemon oil, and in whiskey volatiles is discussed.

Hawthorne, S.B.; Miller, D.J.

1986-11-01

326

Novel surface-active oligofructose fatty acid mono-esters by enzymatic esterification.  

PubMed

This article describes the synthesis of a series of oligofructose monoesters with fatty acids of different chain length (C8, C12, C16 and C18) to obtain food-grade surfactants with a range of amphiphilicity. Reactions were performed in a mixture of DMSO/Bu(t)OH (10/90 v/v) at 60C and catalysed by immobilised Candida antarctica lipase B. MALDI-TOF-MS analysis showed that the crude reaction products were mixtures of unmodified oligofructose and mostly mono-esters. The conversion into mono-esters increased with the length of the fatty acid chain, reflecting the specificity of the lipase towards more lipophilic substrates. Reverse phase solid phase extraction was used to fractionate the products, which lead to sufficient purity (>93%) of the fatty acid esters for functionality testing. It was shown that derivatives of longer (C16 and C18) fatty acids were more efficient in lowering surface tension and gave a much higher dilatational modulus than derivatives of the shorter (C8 and C12) fatty acids. PMID:23411321

van Kempen, Silvia E H J; Boeriu, Carmen G; Schols, Henk A; de Waard, Pieter; van der Linden, Erik; Sagis, Leonard M C

2012-11-16

327

Positional distribution of highly unsaturated fatty acids in triacyl- sn -glycerols of Artemia nauplii enriched with docosahexaenoic acid ethyl ester  

Microsoft Academic Search

This paper presents the positional distribution of fatty acids in triacyl-sn-glycerols (TAG) of Artemia nauplii used in aquaculture as a live food for marine fish larvae. The nauplii were enriched with docosahexaenoic acid (DHA)\\u000a ethyl ester (EE) in the form of gelatin-acacia microcapsules for 4, 18, and 24 h. TAG of the initial, enriched, and unenriched\\u000a Artemia nauplii were subjected

Yasuhiro Ando; Yoshiaki Oomi

2001-01-01

328

Miniemulsion as efficient system for enzymatic synthesis of acid alkyl esters.  

PubMed

The aim of this work is to devise an efficient enzymatic process for the production of linear alkyl esters in aqueous miniemulsion systems. The esterification reactions of linear alcohols and carboxylic acids were performed with three different enzymes, commercial Amano lipase PS from Pseudomonas cepacia, Lipase type VII from Candida rugosa, and lyophilized Fusarium solani pisi cutinase expressed in Saccharomyces cerevisiae SU50. The miniemulsion system shows a high potential for the synthesis of linear alkyl esters, for example, hexyl octanoate, which could be synthesized with an ester yield of 94% using Amano lipase PS. Even with hydrophilic alcohols as ethanol, ethyl decanoate could be obtained with a concentration of 0.45 M and a yield of 62% using F. s. pisi cutinase as catalyst. High esterification rates for ethyl- and hexyloleate in miniemulsion showed a significant shift in cutinase selectivity towards longer chain length carboxylic acids. The stepwise addition of the alcohol led to an increase of the esterification yield. Moreover, increasing the amount of dispersed organic phase, mainly consisting of the substrates, led to a significant increase of the final ester concentration (e.g., concentration of 1.4 M for ethyl decanoate for the esterification with Amano Lipase PS). PMID:20503297

de Barros, Dragana P C; Fonseca, Lus P; Cabral, Joaquim M S; Aschenbrenner, Eugen M; Weiss, Clemens K; Landfester, Katharina

2010-07-01

329

Comparison of infrared spectrophotometric and lead salt-alcohol methods for determination of trans octadecenoic acids and esters  

Microsoft Academic Search

SummaryThe scope and limitations of the lead salt-alcohol method (11, 19) have been defined as a result of observations in the authors'\\u000a laboratories and in others. Trans octadecenoic acids and esters are not determined specifically by this method, and when large\\u000a amounts of cis acids or esters are present, they are also isolated with the solid acid fraction.\\u000a \\u000a The infrared

Daniel Swern; H. B. Knight; O. D. Shreve; M. R. Heether

1950-01-01

330

Synthesis and physical properties of isostearic acids and their esters  

Technology Transfer Automated Retrieval System (TEKTRAN)

Saturated branched-chain fatty acids (sbc-FAs) are found as minor constituents in several natural fats and oils. Sbc-FAs are of interest since they have lower melting points than their linear counterparts and exhibit good oxidative stability; properties that make them ideally suited in a number of ...

331

Chiral olefin-sulfoxide as ligands for rhodium-catalyzed asymmetric conjugate addition of arylboronic acids to unsaturated esters.  

PubMed

An efficient rhodium/olefin-sulfoxide catalyzed asymmetric conjugate addition of organoboronic acids to various unsaturated esters has been developed, where 2-methoxy-1-naphthyl sulfinyl functionalized olefin ligands have been shown to be highly effective, and are especially applicable to unsaturated methyl esters with up to 99% yield and 91% ee. PMID:24129394

Xue, Feng; Wang, Dongping; Li, Xincheng; Wan, Boshun

2013-10-16

332

Effect of culture pH on the D-alanine ester content of lipoteichoic acid in Staphylococcus aureus.  

PubMed Central

The lipoteichoic acid in Staphylococcus aureus growing at high pH values contained very little alanine ester, showing that high overall levels of substitution were not essential for growth. The low alanine content could have resulted from a progressive loss due to base-catalyzed hydrolysis of the labile ester linkages.

MacArthur, A E; Archibald, A R

1984-01-01

333

Single-molecule spectroscopy studies of microenvironmental acidity in silicate thin films.  

PubMed

Single-molecule (SM) spectroscopic methods were employed to study single site variations in the acidity properties of sol-gel-derived silicate films. The pH-sensitive dye Carboxy SNARF-1 (C.SNARF-1) was used to sense film acidity. Its concentration in the films was maintained at nanomolar levels to allow for SMs to be spectroscopically interrogated. The ratio of C.SNARF-1 fluorescence at 580 nm (protonated form) and 640 nm (deprotonated form) was used to characterize local film pH. SM data were acquired both for "untreated" films and for those treated by immersion for either 1 or 8 h in phosphate solutions of different pH. The SM results prove that the spectral variability observed is dominated by static variations in the local matrix acidity. Shorter immersion times lead to relatively broad histograms and broad "titration" curves, providing clear evidence for kinetic limitations to access of certain film environments by the immersion solutions. Films subjected to longer immersion times generally exhibit narrower histograms. Particularly narrow distributions were obtained for films treated near pH 8-9, while much broader histograms were produced near pH 7. These results are attributed to the buffering effects of surface silanols near pH 9 and enhanced pH sensitivity of the dye near pH 7. PMID:15493944

Fu, Yi; Collinson, Maryanne M; Higgins, Daniel A

2004-10-27

334

Low serum cholesteryl ester-docosahexaenoic acid levels in Alzheimer's disease: a case-control study.  

PubMed

Low n-3 polyunsaturated fatty acid (PUFA) status may be associated with neuro-degenerative disorders, in particular Alzheimer's disease, which has been associated with poor dietary fish or n-3 PUFA intake, and low docosahexaenoic acid (DHA) status. The present case-control study used an established biomarker of n-3 PUFA intake (serum cholesteryl ester-fatty acid composition) to determine n-3 PUFA status in patients with Alzheimer's disease, who were free-living in the community. All cases fulfilled the National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association criteria for Alzheimer's disease. Detailed neuropsychological testing and neuroimaging established the diagnosis in all cases. The subjects (119 females and twenty-nine males) aged 76.5 (SD 6.6) years had a clinical dementia rating (CDR) of 1 (SD 0.62) and a mini mental state examination (MMSE) score of 19.5 (SD 4.8). The control subjects (thirty-six females and nine males) aged 70 (SD 6.0) years were not cognitively impaired (defined as MMSE score <24): they had a mean MMSE score of 28.9 (SD 1.1). Serum cholesteryl ester-eicosapentaenoic acid and DHA levels were significantly lower (P<0.05 and P<0.001 respectively) in all MMSE score quartiles of patients with Alzheimer's disease compared with control values. Serum cholesteryl ester-DHA levels were progressively reduced with severity of clinical dementia. DHA levels did not differ in patients with Alzheimer's disease across age quartiles: all were consistently lower than in control subjects. Step-wise multiple regression analysis showed that cholesteryl ester-DHA and total saturated fatty acid levels were the important determinants of MMSE score and CDR. It remains to be determined whether low DHA status in Alzheimer's disease is a casual factor in the pathogenesis and progression of Alzheimer's disease. PMID:12654166

Tully, A M; Roche, H M; Doyle, R; Fallon, C; Bruce, I; Lawlor, B; Coakley, D; Gibney, M J

2003-04-01

335

Allylic oxidation of ent-Kaurenic acid, ent-Kaurenic acid Methyl Ester and ent-Kaurenol  

Microsoft Academic Search

The allylic oxidation of ent-kaurenic acid, ent-kaurenic acid methyl ester, and ent-kaurenol with SeO2\\/H2O2 is presented. The reaction was run in dioxan solution at room temperature stirring for 4 hours. About 0.3 mmol of substrate was treated with 1.2 mmol of SeO2 and 4.1 mmol of H2O2. Treatment of ent-kaurenic acid afforded 56% of ent-15?-hydroxy-kaur-16-en-19-oic acid (2a). Treatment of ent-kaurenic

Rosa Aparicio; Ali Bahsas; Alfredo Usubillaga

2007-01-01

336

Synthesis and antiradical/antioxidant activities of caffeic acid phenethyl ester and its related propionic, acetic, and benzoic acid analogues.  

PubMed

Caffeic acid phenethyl ester (CAPE) is a bioactive component isolated from propolis. A series of CAPE analogues was synthesized and their antiradical/antioxidant effects analyzed. The effect of the presence of the double bond and of the conjugated system on the antioxidant effect is evaluated with the analogues obtained from 3-(3,4-dihydroxyphenyl) propanoic acid. Those obtained from 2-(3,4-dihydroxyphenyl) acetic acid and 3,4-dihydroxybenzoic acid allow the evaluation of the effect of the presence of two carbons between the carbonyl and aromatic system. PMID:23222926

LeBlanc, Luc M; Par, Aurlie F; Jean-Franois, Jacques; Hbert, Martin J G; Surette, Marc E; Touaibia, Mohamed

2012-12-10

337

Metabolism of 14C-labelled sucrose esters of stearic acid in rats.  

PubMed

Rats were dosed by oral gavage (250 mg/kg) with compounds containing sucrose esterified in four, six or eight positions with stearic acid. For each compound, rats excreted greater than 95% of the dose in the faeces. The extent of absorption and metabolism of radioactivity was inversely related to the degree of esterification. For rats dosed with sucrose esters labelled in the fatty acid moieties, the degree of absorption of radioactivity was highest for the tetraesterified compound (5.9% of the dose). At 120 hr after dosing with this derivative, the highest concentrations of radioactivity, aside from tissues of the gastrointestinal tract, were found in fat (183 micrograms-equivalents/g tissue), lymph nodes (117 micrograms-equivalents/g tissue) and the liver (88 micrograms-equivalents/g tissue); appreciable radioactivity appeared in the blood (3.9 micrograms-equivalents/g tissue) and collected lymph (5.0-7.6% of the dose). For rats dosed with esters labelled in the sucrose moiety, the amounts of radioactivity absorbed were lower than after dosing with the corresponding sucrose derivatives labelled in the fatty acid moieties; the absorbed radioactivity was greatest following administration of the tetraesterified compound (3.0%). Relatively little radioactivity was found in tissue samples collected from these rats. These results are consistent with limited hydrolysis of the sucrose esters, presumably to sucrose and fatty acids, prior to intestinal absorption. PMID:9225017

Noker, P E; Lin, T H; Hill, D L; Shigeoka, T

1997-06-01

338

Inhibitory effects of sucrose fatty acid esters, alone and in combination with ethylenediaminetetraacetic acid and other organic acids, on viability of Escherichia coli O157:H7  

Microsoft Academic Search

The effects of sucrose monolaurate (SML), alone in combination with ethylenediaminetetraacetic acid (EDTA), acetic acid, lactic acid, and citric acid, on growth and survival ofEscherichia coliO157:H7 in tryptic soy broth (TSB) were determined. Four food-grade emulsifiers consisting largely of sucrose esters of fatty acids (lauric, palmitic, stearic and oleic) were evaluated for their effects on growth and survival ofE. coliO157:H7

A. K. Hathcox; L. R. Beuchat

1996-01-01

339

TREATMENT OF WOOD WITH POLYSILICIC ACID DERIVED FROM SODIUM SILICATE FOR FUNGAL DECAY PROTECTION1  

Microsoft Academic Search

The aim of this study was to investigate safer, more inexpensive chemicals derived from sodium silicate that can be used to protect wood against fungal degradation. Desiccant and surfactant properties of sodium silicate-derived products have been used since the early 19th century and may find application for wood decay protection. In our study, wood was impregnated with 19.5% sodium silicate

George C. Chen

340

New chiral auxiliaries in enantioselective heterogeneous catalytic hydrogenations: (?) and (+)-dihydro-apovincaminic acid. Comparison with (?)-dihydro-apovincaminic acid ethyl ester. III  

Microsoft Academic Search

The preparation, characterisation, use and comparison with (?)-dihydro-apovincaminic acid ethyl ester of (?) and (+)-dihydro-apovincaminic acid as chiral modifier in heterogeneous catalytic asymmetric hydrogenations are reported. The epimeric compositions were determined using NMR and HPLC methods.

G. Farkas; K. Fodor; A. Tungler; T. Mth; G. Tth; R. A. Sheldon

1999-01-01

341

Lipolase catalyzed synthesis of benzyl esters of fatty acids  

Microsoft Academic Search

Lipolase 100 L, the lipase from the genetically engineered species of Aspergillus oryzae, has been used to catalyze esterification of lauric acid with aromatic alcoholbenzyl alcohol. A kinetic model for the lipase-catalyzed esterification in a biphasic organicaqueous system has been proposed. Based on the interfacial substrate concentration, an analytical rate equation for initial rate of the reaction was derived and

M. S. Shintre; R. S. Ghadge; S. B. Sawant

2002-01-01

342

Bisacylation of the anhydride and esters of 4-methyl-1,2,3,4-tetrahydrophthalic acid  

Microsoft Academic Search

The bisacylation of the anhydride and esters of 4-methyl-1,2,3,4-tetrahydrophthalic acid by anhydrides of carboxylic acids in the presence of perchloric acid results in the formation of derivatives of 1,3-dialkyl-6, 7-dicarboxy-5,6,7,8-tetrahydro-2-benzopyrylium salts. Some reactions of the salts obtained, including their recyclization under the action of nucleophiles, have been studied. A convenient preparative method for the synthesis of 6,7-dicarboalkoxy-5,6,7,8-tetrahydroixoquinolines has been developed.

V. I. Dulenko; V. M. Golyak; N. N. Alekseev; N. F. Gorenko

1984-01-01

343

The identification of bile acid methyl esters by gas chromatography methane chemical ionization mass spectrometry.  

PubMed

Methane chemical ionization mass spectrometric data and gas chromatography retention parameters are reported for 31 bile acid methyl esters. The group includes both saturated and unsaturated compounds with up to three keto or hydroxyl groups. Major ions include the quasimolecular ions and fragments resulting from the loss of neutral species such as methanol, water and methane. The combination of gas-liquid chromatography retention and mass spectral data is sufficient for an unequivocal distinction among all the bile acids studied. Application of this data to the identification of bile acid metabolites is cited. PMID:476290

Muschik, G M; Wright, L H; Schroer, J A

1979-06-01

344

Displacement of the double bonds during hydrogenation of unsaturated fatty acid methyl esters  

Microsoft Academic Search

SummaryThe displacement of the double bond of several unsaturated fatty acid methyl esters during hydrogenation with a nickel-kieselguhr\\u000a catalyst at 180C. was investigated. The analysis of the dicarboxylic acids (obtained by oxidation of the reaction products\\u000a with KMnO4 in acetic acid solution) by means of partition chromatography enabled a reliable semiquantitative determination of the position\\u000a isomers formed.\\u000a \\u000a During hydrogenation of

C. Boelhouwer; J. Gerckens; Ong Tian Lie; H. I. Waterman

1953-01-01

345

Antimicrobial activity of n-6, n-7 and n-9 fatty acids and their esters for oral microorganisms  

PubMed Central

Objective This study is to assess the antibacterial activity of omega-6, -7, -9 (n-6, n-7, n-9) fatty acids against various oral microorganisms. Methods The n-6, n-7, n-9 fatty acids, such as ?-linoleic acid (GLA), linoleic acid (LA), arachidonic acid (ARA), palmitoleic acid (PA), and oleic acid (OA), their fatty acid ethyl esters, GLA-EE, LA-EE, ARA-EE, PA-EE, OA-EE, and their fatty acid methyl esters, GLA-ME, LA-ME, ARA-ME, PA-ME, OA-ME were investigated for antimicrobial activity against oral pathogens Streptococcus mutans, Candida albicans, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum, and Porphyromonas gingivalis. Various concentrations of the fatty acids, their methyl and ethyl esters were tested against various oral pathogens in 96-well plates and blood-agar plate. The plates were incubated anaerobically or aerobically at 37C for 48 hours, and the colony forming units (CFU) were determined. Results The data demonstrated that select n-6, n-7, n-9 fatty acids and their esters exhibited strong antimicrobial activity against these oral microorganisms, demonstrating some specificity for individual microbial species. Conclusion The potential use or the combinations of the n-6, n-7, n-9 fatty acids and/or their esters, provided in a local delivery vehicle to infected sites in the oral cavity, could be considered as an additional therapeutic approach to improving oral health.

Huang, Chifu B.; George, Brian; Ebersole, Jeffery L.

2010-01-01

346

Synthesis of Some N-Carboxy Methyl Amino Acid Esters and an Attempt to Prepare Di-(N-Carboxy Methyl Amino Acids Esters)-Sulphones for Possible Antimicrobial Activity.  

National Technical Information Service (NTIS)

The thesis in organic chemistry discusses the synthesis of some N-carboxy methyl amino acid esters and their testing for possible antimicrobial activity. The end products were determined by various wet tests including ultraviolet and infrared spectroscopy...

T. Pasha

1989-01-01

347

Globosumones A-C, cytotoxic orsellinic acid esters from the Sonoran desert endophytic fungus Chaetomium globosum.  

PubMed

Three new esters of orsellinic acid, globosumones A-C (1-3), and three known compounds, orsellinic acid (4), orcinol, and trichodion (5), were isolated from Chaetomium globosum endophytic on Ephedrafasciculata (Mormon tea). The structures of the new compounds 1-3 were established spectroscopically, which included 2D NMR experiments and 1H NMR studies on Mosher's ester derivatives. All compounds were evaluated for inhibition of cell proliferation in a panel of four cancer cell lines, NCI-H460 (non-small cell lung cancer), MCF-7 (breast cancer), SF-268 (CNS glioma), and MIA Pa Ca-2 (pancreatic carcinoma), and normal human fibroblast cells (WI-38). Only globosumones A (1) and B (2) were found to be moderately active. PMID:15921417

Bashyal, Bharat P; Wijeratne, E M Kithsiri; Faeth, Stanley H; Gunatilaka, A A Leslie

2005-05-01

348

Kinetics and mechanism of thermal decomposition of tert-Butylperoxyethyl esters of carboxylic acids  

SciTech Connect

tert-Butylperoxyethyl esters of carboxylic acids are widely used as vulcanization initiators of saturated elastomers and also as comonomers and inititators in polymerization processes. The kinetics of thermal decomposition of these esters of carboxylic acids were studied in the temperature range of 383-413/sup 0/K. The thermal stability of the peroxides is only slightly influenced by change in the substituent in the acyl part. The differences in the energies of activation are compensated by a change in the value of the preexponential factor. A mechanism of the process has been suggested and discussed. The homolytic cleavage of the -00- bond leads to the formation of inactive acyloxyethoxyl radicals, which undergo further decomposition.

Turovskii, A.A.; Aleinikova, T.P.; Kushch, O.V.; Navrotskii, V.A.; Turovskii, N.A.

1985-07-01

349

The ecotoxicity and the biodegradability of lactic acid, alkyl lactate esters and lactate salts.  

PubMed

The ecotoxicity of lactic acid, its alkyl esters and selected metal salts was studied experimentally with the micro alga Selenastrum capricornutum, the crustacean Daphnia magna and the fish species Brachydanio rerio and Pimephales promelas. In addition, the biodegradation of lactate esters was also studied. The aim of the study was to provide predicted environmental data for additional alkyl homologues and metal salts. The ecotoxicity data are evaluated by means of Structure Activity Relations (SAR), using literature data on a non-polar narcotic mechanism of toxicity as a baseline for comparison. Lactate salts were evaluated by comparison to the toxicity of the metal ion. For the fish and D. magna, it was evident that methyl, ethyl, propyl and to a lesser extent butyl lactate were slightly more toxic in comparison to baseline non-polar narcotic toxicity data. The toxicity tests carried out with lactate-salts demonstrated clearly that the toxicity in standard tests is only determined by the associated cation and not by the lactate part. Lactic acid and its alkyl esters were degraded for more than 60% in the ready biodegradability tests and from the data presented, it is evident that the majority of alkyl lactates are readily biodegradable. The results presented in this study indicate that alkyl lactate esters show some differences in their ecotoxicity when compared to non polar narcotic compounds in but that these differences are generally small. When aquatic toxicity is considered together with their rapid tendency to biodegrade, it is concluded that lactate esters show generally favourable environmental characteristics. PMID:9734323

Bowmer, C T; Hooftman, R N; Hanstveit, A O; Venderbosch, P W; van der Hoeven, N

1998-09-01

350

Merging domino and redox chemistry: stereoselective access to di- and trisubstituted ?,?-unsaturated acids and esters.  

PubMed

Merging is the game! The coupling of a domino reaction and an internal neutral redox reaction constitutes an excellent manifold for the stereoselective synthesis of di- and trisubstituted olefins featuring a malonate unit, an ester, or a free carboxylic acid as substituents at the allylic position (see scheme; MW=microwave). The reaction utilizes simple starting materials (propargyl vinyl ethers), methanol or water as solvents, and a very simple and bench-friendly protocol. PMID:22354501

Tejedor, David; Mndez-Abt, Gabriela; Cotos, Leandro; Garca-Tellado, Fernando

2012-02-22

351

Mediation of oviposition responses in the malaria mosquito Anopheles stephensi Liston by certain fatty acid esters  

Microsoft Academic Search

The chemical factors involved in oviposition site selection by mosquitoes have become the focus of interest in recent years,\\u000a and considerable attention is paid to the chemical cues influencing mosquito oviposition. Studies on synthetic oviposition\\u000a attractants\\/repellents of long-chain fatty acid esters against Anopheles stephensi are limited. Screening and identification of chemicals which potentially attract\\/repel the gravid females to\\/or from oviposition

Kavita R. Sharma; T. Seenivasagan; A. N. Rao; K. Ganesan; O. P. Agrawal; Shri Prakash

2009-01-01

352

L-Methionine Methyl Ester Hydrochloride as a Corrosion Inhibitor of Iron in Acid Chloride Solution  

Microsoft Academic Search

Some aminoester organic compounds were tested as corrosion inhibitors for iron in molar hydrochloric acid (HCl) by mass-loss and electrochemical polarization methods. Both techniques gave the same order of inhibition. Comparison of results among those aminoesters showed L-methionine methyl ester (METOCH) was the best inhibitor. Its inhibition efficiency (E%) reached a maximum value of 95% at 10⁻² M. Polarization measurements

B. Hammouti; M. Taleb; M. Brighli; S. Kertit; A. Aouniti

1995-01-01

353

Iontophoretic delivery of 5-aminolevulinic acid and its methyl ester using a carbopol gel as vehicle  

Microsoft Academic Search

The aim of this study was to evaluate a Carbopol gel as a vehicle for iontophoretic delivery of 5-aminolevulinic acid (ALA) and its methyl ester (m-ALA). The formulation was characterized rheologically and the passive diffusion of ALA and m-ALA in the gels was measured. Addition of ALA and m-ALA did not change the rheological behavior of the gel and the

Nadia Merclin; Tobias Bramer; Katarina Edsman

2004-01-01

354

Analyses of electro-chemical characteristics of Palm Fatty Acid Esters as insulating oil  

Microsoft Academic Search

We have developed a new vegetable based insulating oil for transformers called PFAE (palm fatty acid ester). PFAE has 0.6 times less viscosity and a 1.3 times higher dielectric constant compared to mineral oil. This means that a PFAE-immersed transformer has better cooling efficiency and better insulation characteristics in paper-and-oil composite insulation systems, resulting in size reduction in comparison to

Takaaki Kanoh; Hiroyuki Iwabuchi; Yoshiyuki Hoshida; Junichi Yamada; Tomoyuki Hikosaka; Akina Yamazaki; Yasunori Hatta; Hidenobu Koide

2008-01-01

355

SYNTHESIS OF NOVEL HYDROPHILIC POLY(ESTER-CARBONATES) CONTAINING PENDENT CARBOXYLIC ACID GROUPS  

Microsoft Academic Search

A functional cyclic carbonate, 5-methyl-5-benzyloxycarbonyl-1,3-dioxan-2-one (MBC), was utilized in the synthesis of novel poly(ester-carbonates) containing pendent carboxylic acid groups. Copolymers with ?-caprolactone (CL) and L-lactide (LLA) were synthesized by ring-opening polymerization (ROP) using either an Al-alkoxide (solution) or Sn(Oct)2-alcohol (bulk) initiating system. Analysis of the copolymers revealed a random distribution of the comonomer units along the polymer chain. The copolymers

Robson F. Storey; Brian D. Mullen; Kim M. Melchert

2001-01-01

356

Synthesis and Characterization of Diaminophenylindane Based Polyimides via Ester-Acid Solution Imidization  

Microsoft Academic Search

The solution polycondensation of 1-(4-aminophenyl)-5(6)-aminoindane (DAPI) with a number of commercially available dianhydrides using the two-step ester-acid solution imidization route is described. High molecular weight polyimides were successfully synthesized from a 1:1 molar ratio of dianhydride to diamine. These film-forming systems have high glass transition temperatures (331368 C) and very good short-term thermal stability as judged by differential scanning calorimetry

I V Farr; T E Glass; Q Ji; J E McGrath

1997-01-01

357

Control of the phytopathogen Botrytis cinerea using adipic acid monoethyl ester  

Microsoft Academic Search

The in vitro and in vivo antifungal activity of adipic acid monoethyl ester (AAME) on the necrotrophic pathogen Botrytis cinerea has been studied. This chemical effectively controlled this important phytopathogen, inhibited spore germination and mycelium development at non-phytotoxic concentrations. The effectiveness of AAME treatment is concentration-dependent and influenced by pH. Spore germination in the presence of AAME is stopped at

Begonya Vicedo; Mara de la O Leyva; Vctor Flors; Ivan Finiti; Gemma del Amo; Dale Walters; Maria Dolores Real; Pilar Garca-Agustn; Carmen Gonzlez-Bosch

2006-01-01

358

Quinic acid esters from Pluchea indica with collagenase, MMP-2 and MMP-9 inhibitory activities.  

PubMed

Investigation of collagenase inhibitory natural components afforded two quinic acid esters (1 and 2) and quercetin (3) from the leaves of Pluchea indica (Compositae). Of these, compounds 1 and 2 exhibited collagenase inhibitory activity (IC(50)) at a concentration of less than 10 microm, and 1 showed matrix metalloproteinase (MMP)-2 and -9 inhibitory activity (IC(50)) at 2.5 and 6.4 microm, respectively. PMID:17726735

Ohtsuki, Takashi; Yokosawa, Emiko; Koyano, Takashi; Preeprame, Srisomporn; Kowithayakorn, Thaworn; Sakai, Shinobu; Toida, Toshihiko; Ishibashi, Masami

2008-02-01

359

Human fatty acid ethyl ester synttiase-III gene: Genomic organization, nucleotide sequencing and chromosomal localization  

Microsoft Academic Search

The complete gene for human fatty acid ethyl ester Synthase-III(FAEES-III) was isolated from a human genomic lambda phage library forfunctional and structural determination. The gene spans approximately 3.3 kbwhich includes 791 base pairs of the 5' and 124 base pairs of the 3'flanking regions. The gene is comprised of seven exons and is interrupted bysix introns. Several transcription regulatory sequences

Puran S. Bora; Bandula L. Guruge; D. Douglas Miller; Bernard R. Chaitman; Wilbert Fortson

1997-01-01

360

Protective effect of caffeic acid phenethyl ester against carbon tetrachloride-induced hepatotoxicity in mice  

Microsoft Academic Search

This study was designed to investigate the protective effects of the phenethyl ester of caffeic acid (CAPE) against carbon tetrachoride (CCl4)-induced hepatotoxicities in mice. Pretreatment with CAPE prior to administration of CCl4 significantly prevented the increases in serum alanine, aspartate aminotransferase and alkaline phosphatase activities, hepatic lipid peroxidation formation, and depletion of glutathione content. In addition, CAPE prevented CCl4-induced apoptosis

Kyung Jin Lee; Jae Ho Choi; Tilak Khanal; Yong Pil Hwang; Young Chul Chung; Hye Gwang Jeong

2008-01-01

361

Separation of Ethyl Ester of Docosahexaenoic Acid by Facilitated Transport Membrane with High Stability  

Microsoft Academic Search

The selective transport of the ethyl ester of docosahexaenoic acid (DHA-Et) was studied in the facilitated transport system where feed phase, membrane phase, and receiving phase had the same ethanol diluent. The carrier of DHA-Et was Ag, and a Nafion membrane was used as the support so that Ag was immobilized in the support by electrostatic force. DHA-Et was sufficiently

YOSHIRO KITAMURA; HIDETO MATSUYAMA; AKIHIRO NAKABUCHI; NOBUHIRO MATSUI; YUJI DOI; YORISHIGE MATSUBA

1999-01-01

362

Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase  

Microsoft Academic Search

Lipase enzyme from Aspergillus oryzae (EC 3.1.1.3) was immobilized onto a micro porous polymeric matrix which contains aldehyde functional groups and methyl esters of long chain fatty acids (biodiesel) were synthesized by transesterification of crude canola oil using immobilized lipase. Micro porous polymeric matrix was synthesized from styrenedivinylbenzene (STYDVB) copolymers by using high internal phase emulsion technique and two different

Yasin Ycel; Cevdet Demir; Nadir Dizge; Blent Keskinler

2011-01-01

363

Calculations of phase equilibria for mixtures of triglycerides, fatty acids, and their esters in lower alcohols  

Microsoft Academic Search

The objects of study were mixtures containing triglycerides and lower alcohols and also the products of the transesterification\\u000a of triglycerides, glycerol and fatty acid esters. The Redlich-Kwong-Soave equation of state was used as a thermodynamic model\\u000a for the phase state of the selected mixtures over wide temperature, pressure, and composition ranges. Group methods were applied\\u000a to determine the critical parameters

D. A. Stepanov; A. Ermakova; V. I. Anikeev

2011-01-01

364

Enhancement of antibacterial superoxide-anion generation in human monocytes by fumaric acid esters  

Microsoft Academic Search

Fumaric acid esters (FAE) are used for the systemic therapy of psoriasis with high clinical efficacy. Among the potential\\u000a side effects of FAE therapy, lymphocytopenia is sometimes observed. We have investigated the effect of dimethylfumarate (DMF)\\u000a and its main metabolite methylhydrogenfumarate (MHF) as well as dexamethasone on superoxide anion generation by human monocytes\\u000a and neutrophils after stimulation with bacteria (Staphylococcus

Kejian Zhu; Ulrich Mrowietz

2005-01-01

365

Phthalic acid esters found in municipal organic waste: enhanced anaerobic degradation under hyper-thermophilic conditions  

Microsoft Academic Search

Abstract Contamination of the organic fraction of municipal solid waste (OFMSW) with xenobiotic compounds,and their fate during anaerobic digestion was investigated. The phthalic acid ester di-(2- ethylhexyl)phthalate (DEHP) was identified as the main contaminant in OFMSW in concentrations more,than half of the threshold value for the use as fertilizer on agricultural soil in Denmark. Analysis of DEHP in samples before

H. hartmann; B. k. Ahring

366

Comparison of fatty acid esters of sucrose and of polyoxyethylene in built detergent compositions  

Microsoft Academic Search

The addition of suerose monotallowate to an aqueous solution of alkanolamine alkylaryl sulfonate lowers the total active-agent\\u000a content required for the formation of liquid crystals. In contrast, the addition of polyoxyethylene esters of fatty acids\\u000a to the alkylaryl sulfonate solution increased the total amount of active agent required for the formation of liquid crystals.\\u000a The deaggregating effect of the ethylene

Lloyd I. Osipow; Foster D. Snell

1961-01-01

367

Forward and backward extractions of cytochrome c using reverse micellar system of sucrose fatty acid ester  

Microsoft Academic Search

The effects of solvent, pH, and ionic strength on the reverse micellar extraction of cytochrome c have been examined, when sucrose fatty acid esters were employed as surfactants of reverse micelles. The transparent and stable reverse micellar organic phase was formed, when the mixture of isooctane and n-butanol (7:3v\\/v) was used as the bulk organic phase. The high forward extraction

Hidetaka Noritomi; Saori Ito; Naoki Kojima; Satoru Kato; Kunio Nagahama

2006-01-01

368

Effect of sucrose fatty acid esters on the particle characteristics and flow properties of phytosterol nanodispersions  

Microsoft Academic Search

The effect of four different types of sucrose fatty acid esters as nonionic emulsifiers on the physicochemical properties of water-soluble phytosterol nanodispersions was investigated. In general, the mean particle sizes of the prepared phytosterol nanodispersions ranged from 2.8 to 259.9nm. The phytosterol content in the final prepared nanodispersions ranged from 230.4 to 504.6mg\\/l. All of the prepared phytosterol nanodispersions exhibited

Wai Fun Leong; Yaakob B. Che Man; Oi Ming Lai; Kamariah Long; Mitsutoshi Nakajima; Chin Ping Tan

2011-01-01

369

Refolding of denatured lysozyme by water-in-oil microemulsions of sucrose fatty acid esters  

Microsoft Academic Search

Water-in-oil (w\\/o) microemulsion of sucrose fatty acid ester was used to renature denatured hen egg white lysozyme without\\u000a aggregation. After lysozyme was denatured in 5M guanidine hydrochloride for 24h, the resultant denatured lysozyme was held\\u000a in the microemulsion, overnight at 25C. Renatured lysozyme was transferred from the microemulsion phase to the recovery aqueous\\u000a phase by conventional liquid-liquid extraction. The enzymatic

Hidetaka Noritomi; Tsubasa Takasugi; Satoru Kato

2008-01-01

370

Chronic Toxicity and Carcinogenicity of Sucrose Fatty Acid Esters in Fischer 344\\/DuCrj Rats  

Microsoft Academic Search

A 13-week and a 2-year feeding study were conducted in Fischer 344\\/DuCrj rats to evaluate the oral toxicity and carcinogenicity of S-570, a mixture of mono-, di-, tri-, and higher esters of sucrose with fatty acids derived from edible fats and oils. In both studies, S-570 was fed at 0, 1, 3, or 5% (w\\/w) of the diet to groups

K. Takeda

2002-01-01

371

Refolding of denatured lysozyme by water-in-oil microemulsions of sucrose fatty acid esters.  

PubMed

Water-in-oil (w/o) microemulsion of sucrose fatty acid ester was used to renature denatured hen egg white lysozyme without aggregation. After lysozyme was denatured in 5 M guanidine hydrochloride for 24 h, the resultant denatured lysozyme was held in the microemulsion, overnight at 25 degrees C. Renatured lysozyme was transferred from the microemulsion phase to the recovery aqueous phase by conventional liquid-liquid extraction. The enzymatic activity of the recovered lysozyme was 93%. PMID:18066501

Noritomi, Hidetaka; Takasugi, Tsubasa; Kato, Satoru

2007-12-08

372

Synthesis and size control of silver nanoparticles using reverse micelles of sucrose fatty acid esters  

Microsoft Academic Search

Silver nanoparticles were prepared in reverse micelles of sucrose fatty acid esters. The TEM image showed that the obtained\\u000a silver nanoparticles displayed a wide variety of shapes. The size of silver nanoparticles was strongly dependent upon a kind\\u000a of reducing agents and tended to increase with an increase in reaction temperature. Moreover, the size of silver nanoparticles\\u000a was controlled by

Hidetaka Noritomi; Naohiro Igari; Kenji Kagitani; Yoshihiro Umezawa; Yasutaka Muratsubaki; Satoru Kato

2010-01-01

373

Sucrose fatty acid esters enhance efficiency of foliar-applied urea-nitrogen to soybeans  

Microsoft Academic Search

A greenhouse study is described showing the effect of sucrose fatty acid esters (SFE) applied to soybeans (Glycine max (L.) Merrill cv Fukuyutaka) during the flowering and\\/or pod-filling periods on the efficiency of foliar-applied urea-nitrogen. SFE applied in combination with urea delayed senescence and when applied during both the flowering and pod-filling periods increased seed yields by 103% and nitrogen

M. Ikeda; W. K. Choi; Y. Yamada

1991-01-01

374

Inhibition of Irritation and Contact Hypersensitivity by Phenoxyacetic Acid Methyl Ester in Mice  

Microsoft Academic Search

New anti-irritant treatments are required to prevent irritation and sensitization reactions to consumer medicines and dermatological drugs. We report here that phenoxyacetic acid methyl ester (PAME) is an effective agent to prevent and treat irritant and allergic contact dermatitis. Balb\\/c mice skin-treated with 1% PAME do not lose weight relative to vehicle-treated mice, nor is it irritating to mouse skin.

John J. Wille; Agis Kydonieus; Richard S. Kalish

2000-01-01

375

Synthesis of alkyl glycoside fatty acid esters in non-aqueous media by Candida sp. lipase  

Microsoft Academic Search

Alkyl glycoside fatty acid esters were successfully synthesized by lipase-catalyzed transesterification of methyl glucoside,\\u000a methyl glucoside, methyl galactoside and octyl glucoside with methyl oleate. The experiments were carried out in organic media\\u000a with lipase enzymes fromCandida sp. as biocatalysts. Time course and the effects of temperature, solvent type, substrate concentration, added water and of\\u000a immobilizedvs. nonimmobilized enzyme were studied. The

Lydia N. Mutua; Casimir C. Akoh

1993-01-01

376

Caffeic acid phenethyl ester inhibits nitric oxide synthase gene expression and enzyme activity  

Microsoft Academic Search

Since nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been known to be involved in inflammatory and autoimmune-mediated tissue destruction, modulation of NO synthesis or action represents a new approach to the treatment of inflammatory and autoimmune diseases. Caffeic acid phenethyl ester (CAPE), an active component of honeybee propolis, has been identified to show anti-inflammatory, anti-viral and

Yun Seon Song; Eun-Hee Park; Gang Min Hur; Young Sue Ryu; Yong Sup Lee; Jae Yeol Lee; Yong Man Kim; Changbae Jin

2002-01-01

377

Esters of 1-coumarinylbenzylphosphonic acid-IR-spectroscopic and theoretical elucidation.  

PubMed

The IR-spectroscopic properties of three esters of 1-coumarinylbenzylphosphonic acid are elucidated both in solution and in solid-state. Linear-polarized IR-spectroscopy of oriented colloid suspensions in nematic host is used for experimental IR-characteristic band assignment in solid-state. Theoretical quantum chemical DFT calculations at B3LYP level of theory and 6-31++G** basis set are carried. Theoretical electronic structure and vibrational properties of compounds studied are discussed. PMID:19036630

Nikolova, Rositca D; Zareva, Sonya; Ilieva, Eleonora; Kolev, Tsonko; Koleva, Bojidarka

2008-10-19

378

Pharmacokinetics of anti-psoriatic fumaric acid esters in psoriasis patients  

Microsoft Academic Search

The aim of this study was to evaluate pharmacokinetic parameters of fumaric acid esters (FAE) in psoriasis patients for the\\u000a first time. For this prupose new HPLC assays were developed. Additionally, physicochemical parameters of FAE were determined,\\u000a allowing a better interpretation of the in vivo data. In vivo, monomethylfumarate (MMF) and monoethylfumarate (MEF) were detected\\u000a after t\\u000a lag=120min. T\\u000a max

Martin Rostami-Yazdi; Bernd Clement; Ulrich Mrowietz

2010-01-01

379

Low chain esters of stearic acid as phase change materials for thermal energy storage in buildings  

Microsoft Academic Search

Esterification of different commercial mixtures of stearic and palmitic acid with methyl, butyl and propyl alcohols was undertaken at the laboratory scale and the thermal properties of the esters were determined by Differential Scanning Calorimetry (DSC).Twelve products were obtained with melting points in the interval of 1734C and freezing points in the range of 2032C. About half of them are

D. Feldman; D. Banu; D. Hawes

1995-01-01

380

Determination of environmentally relevant physical-chemical properties of some fatty acid esters  

Microsoft Academic Search

Fat models frequently use input parameters that are defined at environmental conditions. In a recently developed gas-liquid\\u000a chromatography method (GC-VAP), vapor pressures, heats of vaporization, and heat capacity differences (gas-liquid) of fatty\\u000a acid esters are determined over a large temperature range that includes environmental temperatures. This method also allows\\u000a an accurate determination of the normal boiling point temperature of a

Hildo B. Krop; Martin J. M. v. Velzen; John R. Parsons; Harrie A. J. Govers; B. Martin

1997-01-01

381

Generalized Method to Quantify Glycidol Fatty Acid Esters in Edible Oils  

Microsoft Academic Search

We previously reported a method to quantify five species of glycidol fatty acid esters (GEs) in edible oils which used a combination\\u000a of a double solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) using fast HPLC. To expand its\\u000a application, we established a new method using conventional HPLC, which is applicable not only to liquid oils but also to\\u000a solid

Yoshinori Masukawa; Hiroki Shiro; Naoki Kondo; Naoto Kudo

2011-01-01

382

Fatty acid esters of 3-chloropropane-1,2-diol in edible oils  

Microsoft Academic Search

A series of 25 virgin and refined edible oils, obtained from retailers, was analyzed for levels of free 3-chloropropane-1,2-diol (3-MCPD) and 3-MCPD released from esters with higher fatty acids (bound 3-MCPD). Oils containing free 3-MCPD ranging from <3?g?kg (LOD) to 24?g?kg. Surprisingly, bound 3-MCPD levels were much higher and varied between <100 (LOD) and 2462?g?kg. On average, virgin oils had

Z. Zelinkov; B. Svejkovsk; J. Velek; M. Doleal

2006-01-01

383

Experimental technique for kinetic study of hydrogenation of fatty acid methyl esters in vapor phase  

Microsoft Academic Search

A new approach to kinetic studies of fat hydrogenation is discussed. An experimental setup is described in detail. An example\\u000a of reactor performance in hydrogenation of fatty acid methyl esters is given. aPresent address: AB Karlshamns Oljefabriker,\\u000a S-292 00 Karlshamn, Sweden. Notation: c, outlet concentration, mol\\/m3 ; co, inlet concentration, mol\\/m3: cb, concentration in bulk fluid, mol\\/m3 ; cs concentration

J.-O. Lidefelt

1983-01-01

384

Electron paramagnetic resonance studies of gamma-irradiated DL-alanine ethyl ester hydrochloride, L-theanine and L-glutamic acid dimethyl ester hydrochloride  

NASA Astrophysics Data System (ADS)

The electron paramagnetic resonance (EPR) of gamma irradiated powders of DL-alanine ethyl ester hydrochloride, L-theanine and L-glutamic acid dimethyl ester hydrochloride were investigated at room temperature. The observed paramagnetic species were attributed to the CH3?HCOOC2H5, -CH2?HCOOH and -CH2?HCOOCH3 radicals, respectively. Hyperfine structure constants and g-values were determined for these three radicals. Some spectroscopic properties and suggestions concerning the possible structure of the radicals were also discussed.

Ba?kan, M. Halim; Ayd?n, Murat

2013-08-01

385

Evaluation of eye irritation by S-(-)-10,11-dihydroxyfarnesic acid methyl ester secreted by Beauveria bassiana CS1029  

PubMed Central

The aim of this study was to investigate whether S-(-)-10,11-dihydroxyfarnesic acid methyl ester produced by cell subtype Beauveria bassiana CS1029 causes acute toxicity when used for cosmetic purposes by performing an eye irritation test. New Zealand white (NZW) rabbits were treated with a 100 mg/dose of S-(-)-10,11-dihydroxyfarnesic acid methyl ester according to standard procedure guidelines. No significant changes in terms of ocular lesions of the cornea, turbidity of the cornea, swelling of the eyelid or ocular discharge were observed in the methyl ester-treated groups, while sodium dioctyl sulfosuccinate, a positive control, caused severe toxicity. The anatomical and pathological observations indicate that the methyl ester produced by Beauveria bassiana CS1029 did not induce eye irritation in the lenses of the rabbits. The data suggest that the methyl ester evaluated in this study has promising potential as a cosmetic ingredient that does not irritate the eye.

SON, HYEONG-U; LEE, SANG-HAN

2013-01-01

386

GC-based analysis of plant stanyl fatty acid esters in enriched foods.  

PubMed

Approaches for the capillary gas chromatographic (GC) based analysis of intact plant stanyl esters in enriched foods were developed. Reference compounds were synthesized by enzyme-catalyzed transesterifications. Their identities were confirmed by means of mass spectrometry. Using a medium polar trifluoropropylmethyl polysiloxane stationary phase, long-chain plant stanyl esters could be separated according to their stanol moieties and their fatty acid chains. Thermal degradation during GC analysis was compensated by determining response factors; calibrations were performed for ten individual plant stanyl esters. For the analysis of low-fat products (skimmed milk drinking yogurts), the GC separation was combined with a "fast extraction" under acidic conditions. For fat-based foods (margarines), online coupled LC-GC offered an elegant and efficient way to avoid time-consuming sample preparation steps. The robust and rapid methods allow conclusions on both, the stanol profiles and the fatty acid moieties, and thus provide a basis for the authentication of this type of functional food ingredients. PMID:21486072

Barnsteiner, Andreas; Lubinus, Tim; di Gianvito, Angelica; Schmid, Wolfgang; Engel, Karl-Heinz

2011-04-22

387

Disposition of etofibrate, clofibric and nicotinic acid esters, and their products in dogs.  

PubMed

Etofibrate, the ethylene glycol diester of clofibric and nicotinic acids, on intravenous infusion into dogs, has a terminal half-life of 2 min. The intermediate half-esters, the nicotinate and the clofibrate, have respective terminal half-lives of 4.6 and 1.7 min and appear fleetingly when etofibrate is administered. In contrast to the 42-h terminal half-life of clofibric acid, the other final transformation product, nicotinic acid, shows saturable or dose-dependent pharmacokinetics in dogs that conform to the Michaelis-Menten equation with a terminal half-life of 4.4 min at low concentrations (less than 6.9 microM/kg). Three distinct metabolites of nicotinic acid can be identified and assayed chromatographically in the urine. The partition properties were similar to nicotinic acid. Nicotinic acid is excreted 30% unchanged into urine with a renal clearance of 70 mL/min in 27-kg dogs. PMID:4009437

Garrett, E R; Altmayer, P

1985-03-01

388

Electron-impact ionization of benzoic acid, nicotinic acid and their n-butyl esters: An approach to regioselective proton affinities derived from ionization and appearance energy data  

Microsoft Academic Search

Electron-impact ionization mass spectra, the decay of metastable ions, ionization and appearance energies and bond energies, as dissociation energies, are reported for the title compounds. An ionization energy of 9.47eV was obtained for benzoic acid, 9.43eV for benzoic acid n-butyl ester, 9.61eV for nicotinic acid and 9.97eV for nicotinic acid n-butyl ester.Molecular ions of both butyl esters show two common

Joachim Opitz

2007-01-01

389

Lipophilic hydroxytyrosol esters: fatty acid conjugates for potential topical administration.  

PubMed

Hydroxytyrosol is a potent antioxidant natural molecule isolated from olive leaves and fruits. The presence of three hydroxy groups in its structure poses a limit for the topical application of this lead compound. A set of hydroxytyrosol conjugates with fatty acids at different molecular weights were synthesized under mild conditions. The topical delivery features of this new set of antioxidant molecules were evaluated as a function of their permeation profiles through the human stratum corneum and viable epidermis membranes. A dependence on their partition coefficients, their molecular weights, and their isometric configurations was then postulated. Encouraging results prompt further investigations on the polyfunctional role that hydroxytyrosol conjugates could have as agents in both anti-inflammatory and antioxidant therapies. PMID:22014120

Procopio, Antonio; Celia, Christian; Nardi, Monica; Oliverio, Manuela; Paolino, Donatella; Sindona, Giovanni

2011-10-20

390

Omacor (prescription omega-3-acid ethyl esters 90): From severe rhythm disorders to hypertriglyceridemia.  

PubMed

Despite progress made in post-myocardial infarction (MI) revascularization and background therapy for the failing heart, the prevention of adverse cardiac remodeling associated with severe rhythm disorders remains an important drug target. Part of the remodeling can be counteracted by modulating the activity of ion channels and exchangers by omega-3 acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In the GISSI-Prevenzione and GISSI-HF trials, omega-3 fatty acids were administered as ethyl esters (Omacor Solvay Pharmaceuticals) and not as triglycerides present in fish oil. Ethyl esters result in a sustained intestinal absorption of EPA and DHA and require various purification steps during production, thereby minimizing the content of environmental toxins. Also the rather high (38%) DHA content of Omacor should not be ignored since in rats with low dose intake of omega-3 acids, DHA but not EPA inhibited ischemia-induced arrhythmias. In patients on multiple tablets, 840 mg EPA+DHA in one capsule is preferred to increase compliance. It is not justified to refer to Omacor as "n-3 polyunsaturated fatty acid supplementation" or even "fish oil" and, based on controlled clinical trials, there is no evidence that fish oil could be a substitute of Omacor. To avoid further confusion, guidelines should be precise and refer to the medication, eg, as in NICE guideline CG48: "Omega-3-acid ethyl esters treatment licensed for secondary prevention post-MI." The anti-arrhythmogenic action of Omacor should be seen in the context of implantable cardioverter-defibrillator trials (DINAMIT, IRIS) where non-sudden death was increased and total mortality unaltered. However, Omacor administered in the GISSI-HF trial reduced the incidence of severe arrhythmic events and mortality. Also in the GISSI-Prevenzione trial, arrhythmic death and mortality were reduced. At higher dosages (daily, 3-4 g) Omacor exhibits more pronounced cardiovascular benefits and, as a licensed indication, improves hypertriglyceridemia and related lipid parameters. PMID:19629408

Rupp, Heinz

2009-07-27

391

Reaction between drug substances and pharmaceutical excipients: formation of citric acid esters and amides of carvedilol in the solid state.  

PubMed

The reactivity of citric acid towards drug substances in the solid state was examined using the beta-blocker carvedilol as a model compound. The reaction mixtures were analysed by LC-MS, the reaction products were isolated by preparative HPLC, and the structures were elucidated by microprobe NMR spectroscopy. Heating a mixture of solid carvedilol and solid citric acid monohydrate for 96 h at 50 degrees C resulted in the formation of about 3% of a symmetrical ester as well as of a number of other reaction products in smaller amounts. Formation of the symmetrical ester was also observed at room temperature. At 70 degrees C, the amounts of three isomeric esters formed reached 6-8%. The minor reaction products were citric acid amides, O-acetylcarvedilol, and esters of itaconic acid. PMID:18996664

Larsen, Jesper; Cornett, Claus; Jaroszewski, Jerzy W; Hansen, Steen H

2008-10-02

392

A Convenient Method for the Large Scale Preparation of (E)-4Oxo2-Butenoic Acid Ethyl Ester  

Microsoft Academic Search

A one step synthesis of (E)-4-oxo-2-butenoic acid ethyl ester via the reaction of ethyl 2-ethoxy-2-hydroxyacetate and (formylmethylene)triphenylphosphorane is described. The method proceeds in good yield on a molar scale.

Robert G. Franz; Joseph Weinstock

1988-01-01

393

Biodegradation of sucrose poly fatty acid esters in soils.  

PubMed

Sucrose polyesters (SPEs) were applied to soil at rates equivalent to 1062 to 1293 kg per hectare and incubated over periods of 100 to 403 days at 20 +/- 2 degrees C in darkness and at a soil moisture of 40% of the maximum water holding capacity. All applied forms of SPEs were aerobically biodegraded to some degree in both American and German soil. However, the mineralization rates varied considerably and were dependent on both SPE and soil type. For example, sucrose octaoleate underwent slow and limited mineralization in the German soils Speyer and Borstel as well as in the American soil Madera, reaching only 6.9-18.4% mineralisation after over 400 days incubation. The same material in the American soils Hollande, Thermal and Uvalde as well as in the German soil Speicherkoog, reached 35-52% after the same incubation period. Of the SPEs most realistic for use in food products, the more liquid (i.e. with the least saturated fatty acids) underwent the most rapid and extensive mineralization. However, the mineralization rates for these materials were distinctly lower than the corresponding ones for sucrose octaoleate. In all cases the extent of mineralization of the SPEs in soil was significantly lower than that of a control fat (synthetic triglyceride mixture HB307), which typically underwent over 50% mineralization in 60 days. PMID:9204543

Figge, K; Haigh-Baird, S D

1997-06-01

394

Caffeic acid phenethyl ester prevents apoptotic cell death in the developing rat brain after pentylenetetrazole-induced status epilepticus.  

PubMed

Population-based studies suggest that seizure incidence is highest during the first year of life, and early-life seizures frequently result in the development of epilepsy and behavioral alterations later in life. The early-life insults like status epilepticus often lead to epileptogenesis, a process in which initial brain injury triggers cascades of molecular, cellular, and network changes and eventually spontaneous seizures. Caffeic acid phenethyl ester is an active component of propolis obtained from honeybees and has neuroprotective properties. The aim of this study was to investigate whether caffeic acid phenethyl ester exerts neuroprotective effects on the developing rat brain after status epilepticus. Twenty-one dams reared Wistar male rats, and 21-day-old rats were divided into three groups: control group, pentylenetetrazole-induced status epilepticus group, and caffeic acid phenethyl ester-treated group. Status epilepticus was induced on the first day of experiment. Caffeic acid phenethyl ester injections (30mg/kg intraperitoneally) started 40min after the tonic phase of status epilepticus was reached, and the injections of caffeic acid phenethyl ester were repeated over 5days. Rats were sacrificed, and brain tissues were collected on the 5th day of experiment after the last injection of caffeic acid phenethyl ester. Apoptotic cell death was evaluated. Histopathological examination showed that caffeic acid phenethyl ester significantly preserved the number of neurons in the CA1, CA3, and dentate gyrus regions of the hippocampus and the prefrontal cortex. It also diminished apoptosis in the hippocampus and the prefrontal cortex. In conclusion, this experimental study suggests that caffeic acid phenethyl ester administration may be neuroprotective in status epilepticus in the developing rat brain. PMID:24012504

Yi?, Ulu; Topu, Yasemin; Ozbal, Seda; Tu?yan, Kaz?m; Bayram, Erhan; Karakaya, Pakize; Yilmaz, Osman; Kurul, Semra H?z

2013-09-06

395

The isolation of omega-3 polyunsaturated fatty acids and methyl esters of fish oils by silver resin chromatography  

Microsoft Academic Search

Multigram quantities of the highly unsaturated ?3 component from samples of fish oil fatty acids and esters were isolated\\u000a by silver resin chromatography. An XN1010 resin column saturated with silver ions was utilized. Polyunsaturated fatty acid\\u000a (PUFA) esters from fish oil concentrate (FOC) were fractionated based on the number of double bonds by using solvent programming\\u000a (acetonitrile in methanol). Larger

R. O. Adlof; E. A. Emken

1985-01-01

396

The mechanism of low levels of nitrogen dioxide reaction with unsaturated fatty acid esters  

SciTech Connect

Nitrogen dioxide is a toxic air pollutant that exists at less than 0.5 ppm in the atmosphere. This toxic compound is known to initiate autoxidation of unsaturated fatty acids both in vivo and in vitro. When autoxidation occurs in vivo, membrane damage that can lead to cell death can occur. Low concentrations of nitrogen dioxide were shown to react with the polyunsaturated fatty acid esters, methyl linoleate and methyl linoleate, by a H-abstraction mechanism. However, methyl oleate, an unsaturated fatty acid ester, was demonstrated to react with a low concentration of nitrogen dioxide by only an addition mechanism. Although methyl oleate reacts by an addition mechanism, a 50:50 molar solution of methyl oleate and methyl linoleate reacted with a low level of nitrogen dioxide exclusively by a H-abstraction mechanism. Therefore, low levels of nitrogen dioxide will probably react with polyunsaturated fatty acid components of pulmonary lipids by a H-abstraction mechanism forming nitrous acid directly in the cell membrane. Vitamin E was demonstrated to be able to act as a preventative antioxidant in the nitrogen dioxide and methyl linoleate reactions; but vitamin C could not prevent nitrogen dioxide from reacting with methyl linoleate by a H-abstraction mechanism. These results suggest that low levels of nitrogen dioxide will react with polyunsaturated fatty acids by a H-abstraction mechanism and that vitamin E can be used to prevent the reaction from occurring.

Gallon, A.A.

1990-01-01

397

Antioxidant activity of propolis: role of caffeic acid phenethyl ester and galangin.  

PubMed

Propolis, a natural product produced by the honeybee, has been used for thousands of years in folk medicine for several purposes. The extract contains amino acids, phenolic acids, phenolic acid esters, flavonoids, cinnamic acid, terpenes and caffeic acid. It possesses several biological activities such as antiinflammatory, immunostimulatory, antiviral and antibacterial. The exact mode of physiological or biochemical mechanisms responsible for the medical effects, however, is yet to be determined. In this work, we have investigated the antioxidant activity of a propolis extract deprived of caffeic acid phenethyl ester (CAPE). In addition, the activity of CAPE and galangin was also examined. Propolis extract (with and without CAPE) and its active components showed a dose-dependent free radical scavenging effect, a significant inhibition of xanthine oxidase activity, and an antilipoperoxidative capacity. Propolis extract with CAPE was more active than propolis extract without CAPE. CAPE, used alone, exhibited a strong antioxidant activity, higher than galangin. The experimental evidence, therefore, suggests that CAPE plays an important role in the antioxidant activity of propolis. PMID:12495706

Russo, A; Longo, R; Vanella, A

2002-11-01

398

Effect of sucrose fatty acid esters on transdermal permeation of lidocaine and ketoprofen.  

PubMed

The effect of sucrose fatty acid esters on transdermal permeation of lidocaine (LC) and ketoprofen was examined. A drug solution was applied to excised hairless mouse skin pretreated with a sugar ester solution to examine the direct effects of the sugar esters on skin permeability. LC was applied with a pH 6 buffer solution (98.8% ionized), pH 10 buffer solution (99.2% unionized), or propylene glycol, while KP was applied with a pH 6 buffer solution (99.1% ionized), pH 2 buffer solution (98.9% unionized), or propylene glycol. Pretreatment with J-1216 (sucrose laurate, HLB = 16) or J-1205 (sucrose laurate, HLB = 5) significantly increased the permeation of LC from the pH 6 solution and KP from propylene glycol, respectively. The permeability coefficients of the ionized and unionized LC and KP were calculated from the permeability data. The ionized LC and KP permeated even through skin not pretreated with sugar esters, although the permeability coefficients were 24 times and 38 times less than those of the unionized LC and KP, respectively. J-1216 pretreatment increased the permeability of ionized LC from aqueous vehicle 2.7 fold. In the next series of experiments, we formulated 1.5% of J-1205 and J-1216 in various vehicles to examine their effect on the permeation of LC applied on the excised hairless mouse skin with no pretreatment. The results coincided with the results of the pretreatment experiment, and the effect of J-1205 in propylene glycol was more remarkable than that observed in the pretreatment study. When these sugar esters were dissolved in propylene glycol at 1.5%, J-1205 increased significantly the KP permeation rate as well as LC permeation rate, suggesting that the combination of J-1205 and propylene glycol would be a potent vehicle for transdermal formulations. PMID:16141541

Okamoto, Hirokazu; Sakai, Takashi; Danjo, Kazumi

2005-09-01

399

Direct-blackening photographic materials based on cellulose esters and phosphomolybdic acid  

SciTech Connect

The authors have examined the scope for making photographic materials by forming phosphomolybdic structures with cellulose ester groups. The material was made by esterifying cellulose in a melt composed of urea and polyphosphoric acid at 160-170/sup 0/C, with the molybdenum subsequently introduced by sorption from acid (NH/sub 4/)/sub 6/Mo/sub 7/O/sub 24/ solution under static conditions with periodic stirring. Potentiometric titration showed that phosphomolybdate structures are formed. The sensitivity was examined by exposing the material to the polychromatic radiation from a mercury-quartz lamp. Phosphomolybdate blue is formed in the exposed area.

Luneva, N.K.; Komar', V.V.; Oputina, A.G.; Ermolenko, I.N.

1988-11-10

400

[Determination of dimethylformamide in food additive sucrose esters of fatty acids using solid-phase extraction].  

PubMed

A simple method using Florisil cartridges was developed for the determination of dimethylformamide (DMF) in sucrose esters of fatty acids present in sugar esters (SuE) and sucrose acetate isobutyrate (SAIB) used as food additives. SuE was dissolved in acetone and loaded on a Florisil cartridge. SAIB was dissolved in hexane, loaded on a Florisil cartridge and washed with 10% acetone in hexane. The columns were eluted with acetone and DMF in the eluates was determined by GC with an FID detector. Recoveries of DMF at the level of 0.5-100 micrograms/g were 93.3-102.6%. The determination limit was 0.5 microgram/g. PMID:11998317

Haneishi, Nahoko; Uematsu, Yoko; Yasuno, Tetsuko; Hagiwara, Teruhiko; Kabashima, Zyunichiro; Araki, Rie; Kamata, Kunihiro

2002-02-01

401

GROWTH AND DOMOIC ACID PRODUCTION BY PSEUDO-NITZSCHIA SERIATA (BACILLARIOPHYCEAE) UNDER PHOSPHATE AND SILICATE LIMITATION1  

Microsoft Academic Search

Pseudo-nitzschia seriata (Cleve) H. Peragallo iso- lated from Scottish west coast waters was studied in batch culture with phosphate (P) or silicate (Si) as the yield-limiting nutrient at 151 C. This species produced the neurotoxin domoic acid (DA) when either nutrient was limiting but produced more when stressed by Si limitation during the stationary phase. Under P-limiting conditions, exponential growth

Johanna Fehling; Keith Davidson; Christopher J. Bolch; Stephen S. Bates

402

Silicic acid leakage from the Southern Ocean: A possible explanation for glacial atmospheric pCO2  

NASA Astrophysics Data System (ADS)

Using a simple box model, we investigate the effects of a reduced Si:N uptake ratio by Antarctic phytoplankton on the marine silica cycle and atmospheric pCO2. Recent incubation experiments demonstrate such a phenomenon in diatoms when iron is added [Hutchins and Bruland, 1998; Takeda, 1998; Franck et al., 2000]. The Southern Ocean may have supported diatoms with reduced Si:N uptake ratios compared to today during the dustier glacial times [Petit et al., 1999]. A similar reduction in the uptake ratio may be realized with an increased production of nondiatom phytoplankton such as Phaeocystis. Our model shows that reduced Si:N export ratios in the Southern Ocean create excess silicic acid, which may then be leaked out to lower latitudes. Any significant consumption of the excess silicic acid by diatoms that leads to an enhancement in their growth at the expense of coccolithophorids diminishes CaCO3 production and therefore diminishes the carbonate pump. In our box model the combination of a reduced carbonate pump and an open system carbonate compensation draw down steady state atmospheric CO2 from the interglacial 277 to 230-242 ppm, depending on where the excess silicic acid is consumed. By comparison, the atmospheric pCO2 sensitivity of general circulation models to carbonate pump forcing is ~3.5-fold greater, which, combined with carbonate compensation, can account for peak glacial atmospheric pCO2. We discuss the importance of the initial rain ratio of CaCO3 to organic carbon on atmospheric pCO2 and relevant sedimentary records that support and constrain this ``silicic acid leakage'' scenario.

Matsumoto, Katsumi; Sarmiento, Jorge L.; Brzezinski, Mark A.

2002-07-01

403

40 CFR 721.10289 - Hexanedioic acid polymer with aliphatic polyol dihydrogen phosphate aromatic ester (generic).  

Code of Federal Regulations, 2013 CFR

...polymer with aliphatic polyol dihydrogen phosphate aromatic ester (generic). 721...polymer with aliphatic polyol dihydrogen phosphate aromatic ester (generic). (a...polymer with aliphatic polyol dihydrogen phosphate aromatic ester (PMN...

2013-07-01

404

Temperature dependence of the dielectric permittivity of acetic acid, propionic acid and their methyl esters: a molecular dynamics simulation study.  

PubMed

For most liquids, the static relative dielectric permittivity is a decreasing function of temperature, because enhanced thermal motion reduces the ability of the molecular dipoles to orient under the effect of an external electric field. Monocarboxylic fatty acids ranging from acetic to octanoic acid represent an exception to this general rule. Close to room temperature, their dielectric permittivity increases slightly with increasing temperature. Herein, the causes for this anomaly are investigated based on molecular dynamics simulations of acetic and propionic acids at different temperatures in the interval 283-363 K, using the GROMOS 53A6(OXY) force field. The corresponding methyl esters are also considered for comparison. The dielectric permittivity is calculated using either the box-dipole fluctuation (BDF) or the external electric field (EEF) methods. The normal and anomalous temperature dependences of the permittivity for the esters and acids, respectively, are reproduced. Furthermore, in the EEF approach, the response of the acids to an applied field of increasing strength is found to present two successive linear regimes before reaching saturation. The low-field permittivity ?, comparable to that obtained using the BDF approach, increases with increasing temperature. The higher-field permittivity ?' is slightly larger, and decreases with increasing temperature. Further analyses of the simulations in terms of radial distribution functions, hydrogen-bonded structures, and diffusion properties suggest that increasing the temperature or the applied field strength both promote a relative population shift from cyclic (mainly dimeric) to extended (chain-like) hydrogen-bonded structures. The lower effective dipole moment associated with the former structures compared to the latter ones provides an explanation for the peculiar dielectric properties of the two acids compared to their methyl esters. PMID:22383366

Riniker, Sereina; Horta, Bruno A C; Thijssen, Bram; Gupta, Saumya; van Gunsteren, Wilfred F; Hnenberger, Philippe H

2012-03-01

405

Features of separation on polymeric reversed phase for two classes of higher saturated fatty acids esters  

NASA Astrophysics Data System (ADS)

The principles of sorption on polymeric reversed phase (PRP) YMS C30 for members of the two classes of esters formed by higher saturated fatty acids, i.e., lutein diesters ( I) and triacylglycerols ( II), are investigated. It is shown that the logarithm of the retention factor increases nonlinearly with an increase of the length of the acid radical, although the retention on PRP is higher in the case of I and lower in the case of II, compared to their retention on traditional monomeric reversed phase (MRP) Kromasil-100 5C18; however, the equivalence of the contributions to the retention of I that correspond to an identical change in acids, does not depend on the length of the hydrocarbon radical of the second acid. It is noted that the Van't Hoff plot for PRP contains a curve break, indicating a change in the retention mechanism upon a rise in temperature.

Deineka, V. I.; Lapshova, M. S.; Zakharenko, E. V.; Deineka, L. A.

2013-11-01

406

Characterization of Benthic Microbial Community Structure by High-Resolution Gas Chromatography of Fatty Acid Methyl Esters  

PubMed Central

Fatty acids are a widely studied group of lipids of sufficient taxonomic diversity to be useful in defining microbial community structure. The extraordinary resolution of glass capillary gas-liquid chromatography can be utilized to separate and tentatively identify large numbers of fatty acid methyl esters derived from the lipids of estuarine detritus and marine benthic microbiota without the bias of selective methods requiring culture or recovery of the microbes. The gas-liquid chromatographic analyses are both reproducible and highly sensitive, and the recovery of fatty acids is quantitative. The analyses can be automated, and the diagnostic technique of mass spectral fragmentation analysis can be readily applied. Splitless injection on glass capillary gas chromatographic columns detected by mass spectral selective ion monitoring provides an ultrasensitive and definitive monitoring system. Reciprocal mixtures of bacteria and fungi, when extracted and analyzed, showed progressive changes of distinctive fatty acid methyl esters derived from the lipids. By manipulating the environment of an estuarine detrital microbial community with antibiotics and culture conditions, it was possible to produce a community greatly enriched in eucaryotic fungi, as evidenced by scanning electron microscopic morphology. The fatty acid methyl esters from the lipids in the fungus-enriched detritus showed enrichment of the C18 dienoic and the C18 and C20 polyenoic esters. Manipulation of the detrital microbiota that increased the procaryotic population resulted in an absence of large structures typical of fungal mycelia or diatoms, as evidenced by scanning electron microscopy, and a significantly larger proportion of anteiso- and isobranched C15 fatty acid esters, C17 cyclopropane fatty acid esters, and the cis-vaccenic isomer of the C18 monoenoic fatty acid esters. As determined by these techniques, a marine settling community showed greater differences in bacterial as contrasted to microeucaryotic populations when compared with the microbial communities of benthic cores. Images

Bobbie, Ronald J.; White, David C.

1980-01-01

407

Iron and silicic acid concentrations regulate Si uptake north and south of the Polar Frontal Zone in the Pacific Sector of the Southern Ocean  

Microsoft Academic Search

We investigated the relative roles of Fe and silicic acid availabilities in regulating Si uptake rates across the Polar Frontal Zone in the Pacific Sector of the Southern Ocean (5968S, 170W) during the US JGOFS Antarctic Environment Southern Ocean Process Study (AESOPS). Meridional gradients in silicic acid concentration ([Si(OH)4]) of about 0.250.56?Mkm?1 were observed in this area during austral spring

Valerie M. Franck; Mark A Brzezinski; Kenneth H Coale; David M Nelson

2000-01-01

408

Investigation of platelet aggregation inhibitory activity by phenyl amides and esters of piperidinecarboxylic acids.  

PubMed

A series of anilides and phenyl esters of piperidine-3-carboxylic acid (nipecotic acid) were synthesized and tested for the ability to inhibit aggregation of human platelet rich-plasma triggered by adenosine 5'-diphosphate (ADP) and adrenaline. As a rule, amides were about two times more active than the corresponding esters, and derivatives bearing substituents at the para position of the phenyl ring were significantly more active than the meta-substituted ones. Among the tested compounds, 4-hexyloxyanilide of nipecotic acid (18a) was found to be the most active one, its IC(50) value being close to that of the most active bis-3-carbamoylpiperidines reported in literature (ca. 40 micro M) and aspirin (ca. 60 microM) in ADP- and adrenaline-induced aggregation, respectively. Compared with the isomeric 4-hexyloxyanilides of piperidine-2-carboxylic (pipecolinic) and piperidine-4-carboxylic (isonipecotic) acids, compound 18a showed higher activity, and a Hansch-type quantitative structure-activity relationship (QSAR) study highlighted lipophilicity and increase in electron density of the phenyl ring as the properties which mainly increase the antiplatelet activity (r(2)=0.74, q(2)=0.64). The interaction of nipecotoyl anilides with phosphatidylinositol, a major component of the inner layer of the platelet membranes, was investigated by means of flexible docking calculation methods to give an account of a key event underlying their biological action. PMID:12628670

de Candia, Modesto; Summo, Luciana; Carrieri, Antonio; Altomare, Cosimo; Nardecchia, Adele; Cellamare, Saverio; Carotti, Angelo

2003-04-01

409

Silver nitrate-high performance liquid chromatography of fatty methyl esters  

Microsoft Academic Search

Long chain fatty methyl esters have been separated by high performance liquid chromatography on the basis of number, position,\\u000a and geometric configuration of double bonds with a silver nitrate-silicic acid column and benzene solvent. Saturated esters\\u000a are eluted first, followed by methyl elaidate and then methyl oleate. Geometric isomers of methyl 9,12-octadecadienoate and\\u000a of methyl 9,15-octadecadienoate are also well separated.

C. R. Scholfield

1979-01-01

410

The Effect of Dietary Fatty Acid Composition on Liver Retinyl Ester (Vitamin A Ester) Composition in the Rat1'3  

Microsoft Academic Search

The dependenceof liver retinylester (vita min A ester) composition on dietary fatty acid composition was studied in rats. Weanling male Sprague-Dawley rats were fed purified test diets containing 8% of one of 10 test triglycérides(either tributyrin, tricaproin, tricaprylin, trica- prin, trilaurin, trimyristin, tripalmitin, tristearin, triolein, tri- linolein) or corn oil (a mixed triglycéride)for 23 d after an initial 1-wk stabilization

HAROLD C. FÜRR; ANDREW J. CLIFFORD; LLOYD M. SMITH; Ano JAMES A. OLSON

411

QTL for phytosterol and sinapate ester content in Brassica napus L. collocate with the two erucic acid genes.  

PubMed

Improving oil and protein quality for food and feed purposes is an important goal in rapeseed (Brassica napus L.) breeding programs. Rapeseed contains phytosterols, used to enrich food products, and sinapate esters, which are limiting the utilization of rapeseed proteins in the feed industry. Increasing the phytosterol content of oil and lowering sinapate ester content of meal could increase the value of the oilseed rape crop. The objective of the present study was to identify quantitative trait loci (QTL) for phytosterol and sinapate ester content in a winter rapeseed population of 148 doubled haploid lines, previously found to have a large variation for these two traits. This population also segregated for the two erucic acid genes. A close negative correlation was found between erucic acid and phytosterol content (Spearman's rank correlation, r(s) = -0.80**). For total phytosterol content, three QTL were detected, explaining 60% of the genetic variance. The two QTL with the strongest additive effects were mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. For sinapate ester content four QTL were detected, explaining 53% of the genetic variance. Again, a close negative correlation was found between erucic acid and sinapate ester content (r(s) = -0.66**) and the QTL with the strongest additive effects mapped on linkage groups N8 and N13 within the confidence intervals of the two erucic acid genes. The results suggests, that there is a pleiotropic effect of the two erucic acid genes on phytosterol and sinapate ester content; the effect of the alleles for low erucic acid content is to increase phytosterol and sinapate ester content. Possible reasons for this are discussed based on known biosynthetic pathways. PMID:18335203

Amar, Samija; Ecke, Wolfgang; Becker, Heiko C; Mllers, Christian

2008-05-01

412

Electronically Rich N-Substituted Tetrahydroisoquinoline 3-Carboxylic Acid Esters: Concise Synthesis and Conformational Studies.  

PubMed

Recent work in our laboratory has shown that the highly substituted, electronically rich 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (THIQ3CA) scaffold is a key building block for a novel class of promising anticoagulants (Al-Horani et al. J. Med. Chem.2011, 54, 6125-6138). The synthesis of THIQ3CA analogs, especially containing specific, electronically rich substituents, has been a challenge and essentially no efficient methods have been reported in the literature. We describe three complementary, glycine donor-based strategies for high yielding synthesis of highly substituted, electronically rich THIQ3CA esters. Three glycine donors studied herein include hydantoin 1, ()-Boc-?-phosphonoglycine trimethyl ester 2 and ()-Z-?-phosphonoglycine trimethyl ester 3. Although the synthesis of THIQ3CA analogs could be achieved using either of the three, an optimal, high yielding approach for the desired THIQ3CA esters was best achieved using 3 in three mild, efficient steps. Using this approach, a focused library of advanced N-arylacyl, N-arylalkyl, and bis-THIQ3CA analogs was synthesized. Variable temperature and solvent-dependent NMR chemical shift studies indicated the presence of two major conformational rotamers in 3:1 proportion for N-arylacyl-THIQ3CA analogs, which were separated by a high kinetic barrier of ~17 kcal/mol. In contrast, N-arylalkyl and bis-THIQ3CA variants displayed no rotamerism, which implicates restricted rotation around the amide bond as the origin for high-barrier conformational interconversion. This phenomenon is of major significance because structure-based drug design typically utilizes only one conformation. Overall, the work presents fundamental studies on the synthesis and conformational properties of highly substituted, electronically rich THIQ3CA analogs. PMID:22665943

Al-Horani, Rami A; Desai, Umesh R

2012-01-10

413

Electronically Rich N-Substituted Tetrahydroisoquinoline 3-Carboxylic Acid Esters: Concise Synthesis and Conformational Studies  

PubMed Central

Recent work in our laboratory has shown that the highly substituted, electronically rich 1,2,3,4tetrahydroisoquinoline3carboxylic acid (THIQ3CA) scaffold is a key building block for a novel class of promising anticoagulants (Al-Horani et al. J. Med. Chem. 2011, 54, 61256138). The synthesis of THIQ3CA analogs, especially containing specific, electronically rich substituents, has been a challenge and essentially no efficient methods have been reported in the literature. We describe three complementary, glycine donor-based strategies for high yielding synthesis of highly substituted, electronically rich THIQ3CA esters. Three glycine donors studied herein include hydantoin 1, ()-Boc-?-phosphonoglycine trimethyl ester 2 and ()-Z-?-phosphonoglycine trimethyl ester 3. Although the synthesis of THIQ3CA analogs could be achieved using either of the three, an optimal, high yielding approach for the desired THIQ3CA esters was best achieved using 3 in three mild, efficient steps. Using this approach, a focused library of advanced N-arylacyl, N-arylalkyl, and bis-THIQ3CA analogs was synthesized. Variable temperature and solvent-dependent NMR chemical shift studies indicated the presence of two major conformational rotamers in 3:1 proportion for NarylacylTHIQ3CA analogs, which were separated by a high kinetic barrier of ~17 kcal/mol. In contrast, Narylalkyl and bisTHIQ3CA variants displayed no rotamerism, which implicates restricted rotation around the amide bond as the origin for high-barrier conformational interconversion. This phenomenon is of major significance because structure-based drug design typically utilizes only one conformation. Overall, the work presents fundamental studies on the synthesis and conformational properties of highly substituted, electronically rich THIQ3CA analogs.

Al-Horani, Rami A.; Desai, Umesh R.

2012-01-01

414

Optimization of carbohydrate fatty acid ester synthesis in organic media by a lipase from Candida antarctica.  

PubMed

The effect of solvents and solvent mixtures on the synthesis of myristic acid esters of different carbohydrates with an immobilized lipase from C. antarctica was investigated. The rate of myristyl glucose synthesized by the enzyme was increased from 3.7 to 20.2 micromol min(-1) g(-1) by changing the solvent from pure tert-butanol to a mixture of tert-butanol:pyridine (55:45 v/v), by increasing the temperature from 45 degrees C to 60 degrees C, and by optimizing the relative amounts of glucose, myristic acid, and the enzyme preparation. Addition of more than 2% DMSO to the tert-butanol:pyridine system resulted in a reduction of enzyme activity. Lowering the water content of the enzyme preparation below 0.85% (w/w) resulted in significant decreases in enzyme activity, while increasing the water content up to 2.17% (w/w) did not significantly affect the enzyme activity. The highest yields of myristyl glucose were obtained when an excess of unsolubilized glucose was present in the reaction system. In this case, all of the initially solubilized and a significant amount of the initially unsolubilized glucose was converted to the ester within 24 h of incubation, resulting in a myristyl glucose concentration of 34 mg/mL(-1). Myristic acid esters of fructose (22.3 micromol min(-1) g(-1)), alpha-D-methyl-glucopyranoside (26.9 micromol min(-1) g(-1)) and maltose (1.9 micromol min(-1) g(-1)) could also be prepared using the tert-butanol:pyridine solvent system. No synthesis activity was observed with maltotriose, cellobiose, sucrose, and lactose as substrate. PMID:11494215

Degn, P; Zimmermann, W

2001-09-20

415

Synthesis and characterization of phosphonate ester and phosphonic acid containing polymers and blends  

NASA Astrophysics Data System (ADS)

Vinylbenzylphosphonate ester (VBP) was homopolymerized and copolymerized with methyl methacrylate and the reactivity ratio of this pair of monomers was calculated from Finneman-Ross and Kelen-Tudos methods. These methods provided identical values, which are rsb1 (VBP) = 1.23 and rsb2(MMA) = 0.43. The phosphonate ester group, -P = O(OEt)sb2; in VBP and poly(VBP-MMA) copolymers was hydrolysed to phosphonic acid, -P = O(OH)sb2; at room temperature to obtain vinylbenzylphosphonic acid (VBPa) and poly(VBPa-MMA) copolymers. sp1H, sp{13}C & sp{31}P NMR spectroscopy, DSC and FTIR were used to monitor the hydrolysis of these phosphorylated monomers and polymers. The glass transition temperature of PVBP was 13spC as compared to 198spC of PVBPa. The phosphoryl group in the parent polymers acts as a self plasticizing agent resulting in lower glass transition temperature, on the other hand inter and intra hydrogen bonding results in broad and high Tsbg in these hydrolysed polymers. VBP was also polymerized with BisGMA or TEGDM to low conversions. These oligomers were tested in vitro as potential adhesive materials for dental/enamel and composite resins. The phosphonate esters containing polymers show substantial capacity to dissolve the heavy metal salts, e.g., UOsb2(NO)sb3.6Hsb2O and thus provides radiopaque polymers. Excessive sorption of water lead to phase separation and, hence, loss of radiopacity. Thus, an alternate method of synthesis of radiopaque polymers is also described in which radiopacifying agent is covalently linked to polymer backbone. Styryldiphenylbismuth was prepared by the reaction of diphenylbismuthchloride and Grignard of p-bromostyrene, but some other by-products such as triphenylbismuth, distyrylphenyl bismoth were also obtained as revealed by reverse phase HPLC and the yield of the reaction was low. Iodinated monomers VBTIsb3 and IEMIsb3 were prepared by reacting VBC or IEM to triiodophenol in high yields. Decomposition kinetic analysis was done by TGA to estimate the thermal stability of iodinated polymers. Incorporation of 13 wt% of either monomer in MMA or VBP results in radiopacity equivalent to 2 mm of aluminum a standard used in dentistry. Finally the dimethyl vinylphosphonate ester was homopolymerized and copolymerized with VBP. The aliphatic phosphonate ester was blended with cellulose acetate and cellulose acetate butyrate. The crystallinity of CA was completely impeded when 5 wt% of PDMVP was added, and the Flory interaction parameter chi obtained for PDMVP/CA was large and negative indicating a strong interaction between this pair of polymers.

Tamber, Harinder Singh

1997-12-01

416

Paracetamol (acetaminophen) esters of some non-steroidal anti-inflammatory carboxylic acids as mutual prodrugs with improved therapeutic index  

Microsoft Academic Search

Paracetamol (acetaminophen) esters [4a-f] of some acidic NSAIDs were synthesized and evaluated as mutual prodrug forms with the aim of improving the therapeutic index\\u000a through prevention of the gastrointestinal toxicity. The structures of the synthesized esters were confirmed by IR and 1H-NMR spectroscopy and their purity was established by elemental analyses and TLC. In-vitro stability studies revealed that\\u000a the synthesized

T. A. Fadl; F. A. Omar

1998-01-01

417

Winsor behaviour of sucrose fatty acid esters: choice of the cosurfactant and effect of the surfactant composition  

Microsoft Academic Search

The behaviour of various sucrose fatty acid esters blends in pseudoternary mixtures {water\\/methyl stearate\\/sucrose ester+propanol or ethanol} was explored. The qualitative and quantitative analysis of the phases gave information on the distribution of the surfactant and the oil in the polyphasic systems. It was seen that the transitions between Winsor systems of type IIII can be obtained by using propanol

Anne-Sophie Muller; Juliette Gagnaire; Yves Queneau; Marc Karaoglanian; Jean-Paul Maitre; Alain Bouchu

2002-01-01

418

Comparative toxicity of the diarrhetic shellfish poisons, okadaic acid, okadaic acid diol-ester and dinophysistoxin-4, to the diatom Thalassiosira weissflogii  

Microsoft Academic Search

Quantitative structure-activity relationships were determined for the diarrhetic shellfish poisoning (DSP) toxins, okadaic acid (OA), OA diol-ester and dinophysistoxin-4 (DTX-4), using a sensitive bioassay procedure with the diatom Thalassiosira weissflogii. OA diol-ester was found to be nearly as toxic as OA. This result contradicted the accepted idea that only the free acid toxins, such as DTX-1 and OA, are potent

Anthony J. Windust; Michael A. Quilliam; Jeffrey L. C. Wright; Jack L. McLachlan

1997-01-01

419

Autoxidation of the furan fatty acid ester, methyl 9,12-epoxyoctadeca-9,11-dienoate  

Microsoft Academic Search

The objective of this study was to identify autoxidation products of methyl 9,12-epoxyoctadeca-9,11-dienoate (F9,12). Previous work has shown that F9,12 is a product both of autoxidation and singlet oxygen oxidation of the methyl ester derivative of conjugated linoleic acid\\u000a (CLA). F9,12, 95% pure, was synthesized from methyl ricinoleate. The synthetic F9,12 was heated at 50C in sealed tubes containing air.

N. Sehat; M. P. Yurawecz; J. A. G. Roach; M. M. Mossoba; K. Eulitz; E. P. Mazzola; Y. Ku

1998-01-01

420

Development of a New Environment-conscious Transformer Impregnated with Palm Fatty Acid Ester (PFAE)  

NASA Astrophysics Data System (ADS)

We have developed a new environment-conscious transformer impregnated with vegetable based insulating oil which called PFAE (Palm Fatty Acid Ester). PFAE has 0.6 times less viscosity and 1.3 times higher dielectric constant compared to mineral oil. This means that a PFAE immersed transformer has better cooling efficiency and better insulating performance in paper-and-oil composite insulation systems, resulting in size reduction in comparison to conventional mineral oil immersed transformers. In this paper, insulating performance of lead to plane electrode models, cooling performance of a PFAE immersed transformer, and the result of analytical study of dissolved gas for abnormal diagnosis are described.

Hikosaka, Tomoyuki; Yamazaki, Akina; Hatta, Yasunori; Koide, Hidenobu; Kanoh, Takaaki; Suzuki, Takashi; Yamada, Junichi; Uemura, Shingo

421

Characteristic fragmentation behaviors of novel dithiocarbamic acid esters studied by electrospray ionization tandem mass spectrometry  

NASA Astrophysics Data System (ADS)

The fragmentation patterns of a novel kind of dithiocarbamic acid esters with excellent anticancer activity were analyzed by positive ion electrospray ionization mass spectrometry in conjunction with tandem mass spectrometry (ESI/MSn). The fragmentation patterns of sodium adduct ions [M + Na]+ were characterized with elimination of hydrogen cyanide and most of their counterparts could be observed. The fragmentation patterns of protonated molecular ions [M + H]+ were characterized with single bond cleavage between thiocarbonyl group and nitrogen atom, and between thiocarbonyl group and sulfur atom. The piperazine moiety of the molecular of [M + H]+ favors a rearrangement to expel azirane, and the suggested rearrangement mechanism is consistent with experimental observations.

Hou, Xueling; Sha, Yaowu; Wang, Xin; Ge, Zemei; Li, Runtao

2005-12-01

422

Acridinyl methyl esters as photoactive precursors in the release of neurotransmitter amino acids.  

PubMed

An investigation of the use of an azaheterocycle, acridine, as an alternative photochemically removable protecting group for the carboxylic function of neurotransmitter amino acids was carried out. 9-Bromomethylacridine was used in the reaction with glycine, alanine, glutamic acid, ?-alanine and ?-aminobutyric acid, to obtain model ester derivatives, which were irradiated at different wavelengths in a photochemical reactor. The process was followed by HPLC/UV, resulting in the release of the active molecule in short irradiation times. The results obtained using 419 nm irradiation show promise (35-98 min) for practical purposes. The compounds were further characterised via time-resolved fluorescence to elucidate their photophysical properties and determine the decay kinetics. PMID:23064410

Piloto, Ana M; Hungerford, Graham; Costa, Susana P G; Gonalves, M Sameiro T

2012-10-15

423

Determination of acid dissociation constant of degradable tetrabromophenolphthalein ethyl ester by capillary zone electrophoresis.  

PubMed

An acid dissociation constant of tetrabromophenolphthalein ethyl ester (TBPE) was determined through the measurement of electrophoretic mobility by capillary zone electrophoresis (CZE). Although TBPE is degradable in acidic pH region and it gradually degraded at pH conditions around and below its pKa values in the time scale of the CZE measurement, equilibrium species of interest were detected as a peak-shaped signal with tailing of the degraded species. Changes in electrophoretic mobility of the equilibrium species of TBPE were analyzed at its detectable pH range in the presence of phenol red as a mobility standard. An acid dissociation constant of 3.47 0.06 (pK(a), I = 0.01, 25C, standard error) was determined for TBPE. PMID:23665628

Takayanagi, Toshio; Tabara, Ayumi; Kaneta, Takashi

2013-01-01

424

An efficient preparation of N-methyl-alpha-amino acids from N-nosyl-alpha-amino acid phenacyl esters.  

PubMed

In this paper we describe a simple and efficient solution-phase synthesis of N-methyl-N-nosyl-alpha-amino acids and N-Fmoc-N-methyl-alpha-amino acids. This represents a very important application in peptide synthesis to obtain N-methylated peptides in both solution and solid phase. The developed methodology involves the use of N-nosyl-alpha-amino acids with the carboxyl function protected as a phenacyl ester and the methylating reagent diazomethane. An important aspect of this synthetic strategy is the possibility to selectively deprotect the carboxyl function or alternatively both amino and carboxyl moieties by using the same reagent with a different molar excess and under mild conditions. Furthermore, the adopted procedure keeps unchanged the acid-sensitive side chain protecting groups used in Fmoc-based synthetic strategies. PMID:20121053

Leggio, Antonella; Belsito, Emilia Lucia; De Marco, Rosaria; Liguori, Angelo; Perri, Francesca; Viscomi, Maria Caterina

2010-03-01

425

Identification of Organic Sulfate Esters in d-Limonene Ozonolysis SOA Under Acidic Condition  

NASA Astrophysics Data System (ADS)

Secondary organic aerosol (SOA) components from gas phase ozonolysis of d-limonene were investigated in a series of indoor chamber experiments. The compounds smaller than 300 Da were quantified using capillary electrophoresis coupled to electrospray ionisation ion trap mass spectrometry (CE/ESI-ITMS). HPLC coupled to an ESI-TOFMS and an ESI-ITMS was used for structural study of dimmers and oligomers. Only 10% of the produced SOA could be attributed to low molecular weight carboxylic acids (Mw<300). The oxidation products which have molecular weights over 300 were detected regardless of the seed particle acidity but the concentrations of these compounds were much higher for acidic seed particle experiments. Strong signals of the compounds with mass to charge ratios (m/z) 281, 465 and 481 were detected when sulphuric acid was used in the seed particles. These compounds showed a strong fragment of m/z 97 in MS2 or MS3 spectra indicating the presence of sulfate in the structures. HPLC/ESI-TOFMS analysis suggests the elemental compositions of C10H17O7S-, C20H33O10S- and C20H33O11S- for m/z 281, 465 and 481, respectively. Based on MS^{n} and TOFMS results, they are most likely organic sulfate esters, possibly formed by a heterogeneous acid catalyzed reaction of a limonene oxidation product and sulfuric acid in the particle phase. The concentrations of the organic sulfate ester were as high as 3.7 ?gm-3 for m/z 281.

Iinuma, Y.; Mueller, C.; Boege, O.; Herrmann, H.

2006-12-01

426

n-alkanes, fatty acid esters, and fatty acid salts in size fractionated aerosols collected over the Mediterranean Sea  

NASA Astrophysics Data System (ADS)

The n-alkanes, fatty acid esters, and fatty acid salts have been analyzed in size fractionated aerosols collected over the Mediterranean Sea using a five-stage cascade impactor. Two main sources of n-alkanes have been identified: terrestrially derived n-alkanes evenly distributed over the whole particle size spectrum and anthropogenic n-alkanes predominantly carried by submicron particles. The comparison between the fatty acid ester (FAE) and fatty acid salt (FAS) particle size distributions allowed an important contribution to be ascertained of the marine source in aerosols ranging from 7.2 to 3.0 ?m under rough weather conditions that may be due to larger bubble produced particles. In contrast, FAE and FAS were evenly distributed from the first to the fifth stage, when collected during calm sea surface conditions. Higher values of the degree of unsaturation of FAE and FAS were associated with mass concentration maxima observed on stages 2 and 3 in IMP1 aerosol sample whereas lower values were found on the other stages in the same sample, and over the whole particle size spectrum in IMP2 aerosol sample collected during calm weather conditions. THe data we present here are discussed in terms of jet and film drop ejections and degradation processes.

Sicre, M.-A.; Marty, J.-C.; Saliot, A.

427

Separation of fatty acids or methyl esters including positional and geometric isomers by alumina argentation thin-layer chromatography.  

PubMed

This paper describes novel and rapid thin-layer chromatography procedures for the analysis of fatty acids and methyl esters using silver-impregnated alumina sheets. These techniques are known in most laboratories, and the equipment is readily available. The fatty acid method allows a separation of petroselinic (C18:1 delta 6c), oleic (C18:1 delta 9c), elaidic (C18:1 delta 9t), erucic (C22:1 delta 13c), and brassidic acids (C22:1 delta 13t), and the methyl ester method gives an excellent resolution with respect to the number, configuration, and position of the unsaturated centers. Sufficient separation for the subsequent ozonolysis and chromatographic quantification of isomeric C18 and C22 fatty acid methyl esters is obtained with both methods. PMID:3611285

Breuer, B; Stuhlfauth, T; Fock, H P

1987-07-01

428

Fatty acid esters of 3-chloropropane-1,2-diol in edible oils.  

PubMed

A series of 25 virgin and refined edible oils, obtained from retailers, was analyzed for levels of free 3-chloropropane-1,2-diol (3-MCPD) and 3-MCPD released from esters with higher fatty acids (bound 3-MCPD). Oils containing free 3-MCPD ranging from <3 microg kg-1 (LOD) to 24 microg kg-1. Surprisingly, bound 3-MCPD levels were much higher and varied between <100 (LOD) and 2462 microg kg-1. On average, virgin oils had relatively low levels of bound 3-MCPD, ranging from <100 (LOD) to <300 microg kg-1 (LOQ). Higher levels of bound 3-MCPD were found in oils from roasted oilseeds (337 microg kg-1) and in the majority of refined oils (<300-2462 microg kg-1), including refined olive oils. In general, it appears that the formation of bound 3-MCPD in oils is linked to preliminary heat treatment of oilseeds and to the process of oil refining. Analysis of unrefined, de-gummed, bleached, and deodorized rapeseed oil showed that the level of bound MCPD decreased during the refining process. However, additional heating of seed oils for 30 min at temperatures ranging from 100 to 280 degrees C, and heating at 230 degrees C (260 degrees C) for up to 8 h, led to an increase in bound 3-MCPD levels. On the other hand, heating of olive oil resulted in a decrease in bound 3-MCPD levels. For comparison, fat isolated from salami was analyzed for intact fatty acid esters of 3-MCPD. This fat contained bound 3-MCPD at a level of 1670 microg kg-1 and the fatty acid esters of 3-MCPD mainly consisted of 3-MCPD diesters; monoesters of 3-MCPD were present in smaller amounts. The major types of 3-MCPD diesters (about 85%) were mixed diesters of palmitic acid with C18 fatty acids (stearic, oleic, linoleic acids). These diesters were followed by 3-MCPD distearate (11%) and 3-MCPD dipalmitate (4%). Generally, very little 3-MCPD existed as the free compound (31 microg kg-1). PMID:17118872

Zelinkov, Z; Svejkovsk, B; Velsek, J; Dolezal, M

2006-12-01

429

Evidence of a Specific Action on the Central Nervous System by the Esters of Some Plant Growth Regulator Acids  

Microsoft Academic Search

THE pharmacology of plant-growth regulator acids has been little studied ; nevertheless, these substances which react in minute traces in green plants possess intense biological activity. We have prepared various esters of these acids with the intention, of studying their action on the central nervous system. Dimethylaminoethanol was chosen as the agent of esterification because Pfeiffer et al.1 had demonstrated

J. Thuillier; GERMAINE THUILLIER; P. RUMPF

1960-01-01

430

Characterization of spirochetal isolates from arthropods collected in South Moravia, Czech Republic, using fatty acid methyl esters analysis  

Microsoft Academic Search

Aim of this study was to evaluate cellular fatty acid analysis for characterization of spirochetes. Strains were isolated from arthropods collected in South Moravia, Czech Republic. Fatty acid methyl esters (FAME) profile was determined for five Borrelia burgdorferi sensu lato (s.l.) strains isolated from Ixodes ricinus ticks, one Spironema culicis strain recovered from mosquito Culex pipiens and seven spirochetal strains

Leona ?echov; Eva Durnov; Silvie ikutov; Ji??? Halouzka; Miroslav N?mec

2004-01-01

431

21 CFR 582.4101 - Diacetyl tartaric acid esters of mono- and diglycerides of edible fats or oils, or edible fat...  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Diacetyl tartaric acid esters of mono- and diglycerides of edible...or oils, or edible fat-forming fatty acids. 582.4101 Section 582.4101 Food...Agents § 582.4101 Diacetyl tartaric acid esters of mono- and diglycerides of...

2013-04-01

432

Novel solvent hydrogen-bonding effects in the singlet oxygen ene reaction: a comparison of ?,?-unsaturated esters and acids  

Microsoft Academic Search

The photooxidations of tiglic acid, angelic acid, 2,3-dimethyl-2-butenoic acid and their corresponding methyl esters using singlet oxygen were investigated in methanol and methanol\\/water solvent mixtures and compared to non-hydrogen-bonding solvents with different dielectric constants. The major and minor ene allylic hydroperoxide products were quantified and this ratio for the acids was found to be dependent on a hydrogen-bonding interaction between

Kristina L Stensaas; Jason A Payne; Alexa N Ivancic; Anisha Bajaj

2002-01-01

433

Preparation of stearoyl lactic acid ester catalyzed by lipases from Rhizomucor miehei and porcine pancreas optimization using response surface methodology  

Microsoft Academic Search

The esterification reaction between stearic acid and lactic acid using Rhizomucor miehei lipase and porcine pancreas lipase was optimized for maximum esterification using response surface methodology. The formation\\u000a of the ester was found to depend on three parameters namely enzyme\\/substrate ratio, lactic acid (stearic acid) concentration\\u000a and incubation period. The maximum esterification predicted by theoretical equations for both lipases matched

K. R. Kiran; N. G. Karanth; S. Divakar

1999-01-01

434

Electrical properties of pSi/[6,6] phenyl-C61 butyric acid methyl ester/Al hybrid heterojunctions: Experimental and theoretical evaluation of diode operation  

NASA Astrophysics Data System (ADS)

In this work, we analyze electrically the Al/p-Si/[6,6] phenyl-C61 butyric acid methyl ester/Al hybrid heterojunction. The barrier height at the p-Si/PCBM interface corresponding to the difference between Si valence band edge and the lowest unoccupied molecular orbital energy level of PCBM is studied with current-voltage (J-V) and capacitance-voltage (C-V) methods and determined to be ~=0.55 eV. This value is in agreement with the onset energy of spectrally resolved photocurrent measurements presented in a previous publication [Matt et al., Adv. Mater. 22, 647 (2010)]. For the J-V characteristics, a thorough model based on an interface generation-recombination current is proposed. All relevant energy levels for this model are obtained experimentally. As origin of the large reverse current, the thermal generation of charge carriers throughout the Si depletion region is identified by the thermal activation measurements.

Bednorz, Mateusz; Fromherz, Thomas; Matt, Gebhard J.; Brabec, Christoph J.; Scharber, Markus; Serdar Sariciftci, N.

2012-12-01

435

A monolithic lipase reactor for biodiesel production by transesterification of triacylglycerides into fatty acid methyl esters  

PubMed Central

An enzymatic reactor with lipase immobilized on a monolithic polymer support has been prepared and used to catalyze the transesterification of triacylglycerides into the fatty acid methyl esters commonly used for biodiesel. A design of experiments procedure was used to optimize the monolithic reactor with variables including control of the surface polarity of the monolith via variations in the length of the hydrocarbon chain in alkyl methacrylate monomer, time of grafting of 1-vinyl-4,4-dimethylazlactone used to activate the monolith, and time used for the immobilization of porcine lipase. Optimal conditions involved the use of a poly(stearyl methacrylate-co-ethylene dimethacrylate) monolith, grafted first with vinylazlactone, then treated with lipase for 2 h to carry out the immobilization of the enzyme. Best conditions for the transesterification of glyceryl tributyrate included a temperature of 37C and a 10 min residence time of the substrate in the bioreactor. The reactor did not lose its activity even after pumping through it a solution of substrate equaling 1,000 reactor volumes. This enzymatic reactor was also used for the transesterification of triacylglycerides from soybean oil to fatty acid methyl esters thus demonstrating the ability of the reactor to produce biodiesel.

Urban, Jiri; Svec, Frantisek; Frechet, Jean M.J.

2011-01-01

436

Microbial dynamics in anaerobic enrichment cultures degrading di-n-butyl phthalic acid ester.  

PubMed

Although anaerobic biodegradation of di-n-butyl phthalic acid ester (DBP) has been studied over the past decade, only little is known about the microorganisms involved in the biological anaerobic degradation pathways. The aim of this work is to characterize the microbial community dynamics in enrichment cultures degrading phthalic acid esters under methanogenic conditions. A selection pressure was applied by adding DBP at 10 and 200 mg L(-1) in semi-continuous anaerobic reactors. The microbial dynamics were monitored using single strand conformation polymorphism (SSCP). While only limited abiotic losses were observed in the sterile controls (20-22%), substantial DBP biodegradation was found in the enrichment cultures (90-99%). In addition, significant population changes were observed. The dominant bacterial species in the DBP-degrading cultures was affiliated to Soehngenia saccharolytica, a microorganism described previously as an anaerobic benzaldehyde degrader. Within the archaeal community, there was a shift between two different species of the genus Methanosaeta sp., indicating a highly specific impact of DBP or degradation products on archaeal species. RNA-directed probes were designed from SSCP sequences, and FISH observations confirmed the dominance of S. saccharolytica, and indicated floccular microstructures, likely providing favourable conditions for DBP degradation. PMID:18754780

Trably, Eric; Batstone, Damien J; Christensen, Nina; Patureau, Dominique; Schmidt, Jens E

2008-08-05

437

The effect of elevated temperature on the strength parameters of silica acid ester consolidated porous limestones  

NASA Astrophysics Data System (ADS)

The porous limestone is one of the most widespread construction materials of the monuments in Central Europe, with emblematic buildings in Vienna, Bratislava, Budapest and many other cities of Austria, Slovakia, Czech Republic and Hungary. The restoration of these monuments very often requires the consolidation of the porous limestone material, where various types of consolidants are used to strengthen the highly weathered stone. Our research focused on the understanding of the behaviour of consolidated porous limestone when the material is subjected to higher temperatures. Test procedure included the preparation of cylindrical test specimens from the Miocene porous limestone which was followed by consolidation by four various types of silica acid ester. The samples after consolidation were heated to 300 and 600 C in electric oven. The material properties such as ultrasonic pulse velocity, density were tested before and after the treatment. Indirect tensile strength (Brazilian test) was used to compare the strength parameters of non treated and consolidated samples. Silica acid ester treated samples after heating were also measured in terms of strength, density and ultrasonic pulse velocity. The results show that there are significant changes in strength of various pre-treated samples after heating indicating the sensitivity of the materials to temperature changes and accidental fire.

Ppay, Zita; Trk, kos

2013-04-01

438

Effects of fatty acid sucrose esters on ceftibuten transport by rat intestinal brush-border membrane vesicles.  

PubMed

The effects of fatty acid sucrose esters on membrane lipid dynamics and ceftibuten transport by rat intestinal brush-border membrane vesicles (BBMV) were examined to clarify the differences in the action of mono- and poly-acyl sucrose esters on the drug transport. Fatty acid sucrose mono-acyl ester (SS) inhibited ceftibuten transport by BBMV similar to the action of polyoxyethylene sorbitans (Tweens), while fatty acid sucrose polyacyl ester mixtures (F-160 and F-140) did not affect the drug transport by BBMV. SS but not F-160 and F-140 caused an increase in the anisotropy of 1,6-diphenyl-1,3,5-hexatriene (DPH)- and 1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene iodide (TMA-DPH)-labeled BBMV in a concentration-dependent manner. Thus, the uptake of ceftibuten by BBMV was strongly correlated with the lipid fluidity of BBMV, in the outer layer and in the inner hydrophobic regions; however, there was no strong correlation between the membrane lipid fluidity and the drug uptake by BBMV. The micelle size and the size distribution of F-160 and F-140 were larger and more widely dispersed, respectively, compared to those of SS and Tweens. These results suggest that the effects of fatty acid sucrose esters on ceftibuten transport by BBMV are related to the dispersion parameter of these pharmaceutical adjuvants. PMID:9703261

Koga, K; Murakami, M; Kawashima, S

1998-07-01

439

Sucrose fatty acid esters suppress pancreatic secretion accompanied by peptide YY release in pancreatico-biliary diverted rats.  

PubMed

Our previous study demonstrated that intestinal administration of triglycerides suppressed protein-induced increases in pancreatic exocrine secretion in pancreatico-biliary diverted (PBD) rats, though the mechanism has not been clarified. The present study was conducted to determine whether esterified fatty acids or free fatty acids are responsible for this suppression, and whether an esterified fatty acid stimulates secretion of a pancreatic inhibitory hormone, peptide YY (PYY). We examined the effects of cocoa butter or non-digestible sucrose fatty acid esters on protein-induced pancreatic secretion in conscious PBD rats whose bile-pancreatic juice was diverted from the proximal small intestine through a catheter. Intraduodenal administration of the protein guanidinated casein hydrolysate (HGC, 150 mg in 1 ml water) enhanced pancreatic protein and trypsin secretion. However, administration of HGC with cocoa butter (100 mg ml(-1)) partly suppressed the increase in pancreatic secretion, and HGC with a highly esterified sucrose fatty acid ester, F-10 (100 mg ml(-1)), completely suppressed it. The low-esterified, water-soluble sucrose fatty acid ester F-160 also completely inhibited protein-induced pancreatic secretion in the presence or absence of the lipase inhibitor orlistat. In anaesthetized PBD rats, intraduodenal administration of HGC with sucrose ester F-160 suppressed HGC-induced pancreatic secretion, and induced PYY secretion more strongly than HGC with sucrose. These results suggest that the esterified fatty acid itself stimulates PYY release in the distal intestine, thereby inhibiting protein-induced pancreatic secretion. PMID:17384118

Hira, Tohru; Takahashi, Katsuhiko; Hara, Hiroshi

2007-03-23

440

Quantitative determination of 5-aminolaevulinic acid and its esters in cell lysates by HPLC-fluorescence.  

PubMed

The development of a reliable sensitive method for the HPLC determination of 5-aminolaevulinic acid (ALA) and ALA esters in cell lysates is described. The method relies on the quantification of a fluorescent derivative of ALA following its derivatisation with acetylacetone and formaldehyde. Following this procedure it is possible to quantify ALA in cell lysates with no need for pre-purification of the sample. The method has been validated in two ranges of concentration (0.6-65 microM, 0.1-10 microg/mL, and 30-600 microM, 5-100 microg/mL), and has also been extended and validated for the determination of ALA released from ALA prodrugs after acidic hydrolysis. PMID:18945649

Giuntini, Francesca; Bourr, Ludovic; Macrobert, Alexander J; Wilson, Michael; Eggleston, Ian M

2008-10-02

441

Fatty acid ethyl ester synthesis in the preparation of scotch whiskey.  

PubMed

Fatty acid ethyl esters (FAEE), nonoxidative ethanol metabolites present in human organs commonly damaged by ethanol abuse, have been implicated as mediators of organ damage. FAEE are additives in various foods and beverages to provide flavor or fragrance, and therefore are common dietary lipid constituents. We hypothesized that FAEE could be generated during alcoholic beverage production because fatty acids are present within microorganisms and ethanol is generated during the fermentation process. In this report, we demonstrate that FAEE are present in commercially available scotch beverages, and that in the preparation of scotch, FAEE can be produced during the fermentation reaction as a result of FAEE synthase activity in the yeast. Following ingestion of scotch, preformed FAEE are delivered to GI tract. The consequences of ingestion of FAEE in scotch, if any, remain to be determined. PMID:10231172

Goss, K A; Alharethi, R; Laposata, M

1999-04-01

442

Highly Functionalized 1,2-Diamino Compounds through Reductive Amination of Amino Acid-Derived ?-Keto Esters  

PubMed Central

1,2-Diamine derivatives are valuable building blocks to heterocyclic compounds and important precursors of biologically relevant compounds. In this respect, amino acid-derived ?keto esters are a suitable starting point for the synthesis of ?,?diamino ester derivatives through a two-step reductive amination procedure with either simple amines or ?amino esters. AcOH and NaBH3CN are the additive and reducing agents of choice. The stereoselectivity of the reaction is still an issue, due to the slow imine-enamine equilibria through which the reaction occurs, affording mixtures of diastereoisomers that can be chromatographically separated. Transformation of the ?,?diamino esters into pyrrolidinone derivatives allows the configuration assignment of the linear compounds, and constitutes an example of their potential application in the generation of molecular diversity.

Perez-Faginas, Paula; Aranda, M. Teresa; Garcia-Lopez, M. Teresa; Infantes, Lourdes; Fernandez-Carvajal, Asia; Gonzalez-Ros, Jose Manuel; Ferrer-Montiel, Antonio; Gonzalez-Muniz, Rosario

2013-01-01

443

Occurrence of 3-MCPD fatty acid esters in human breast milk.  

PubMed

A series of twelve breast milk samples were analysed by gas chromatography-mass spectrometry (GC/MS) operated in selected ion monitoring mode for 3-chloropropane-1,2-diol (3-MCPD). Whilst none of the samples contained 3-MCPD above the limit of detection of 3 microg kg(-1) milk, all contained high amounts of 3-MCPD esterified with higher fatty acids. The levels of 3-MCPD released by hydrolysis of these esters (bound 3-MCPD) ranged from the limit of detection (300 microg kg(-1), expressed on a fat basis) to 2195 microg kg(-1); with a mean level of bound 3-MCPD of 1014 microg kg(-1), which corresponded to 35.5 microg kg(-1) milk. The presence of bound 3-MCPD was confirmed using orthogonal gas chromatography coupled with high-speed time-of-flight mass spectrometry analysis for four randomly selected breast milk samples. Six breast milks collected from one of the nursing mothers 14-76 days after childbirth contained bound 3-MCPD within the range of 328-2078 microg kg(-1) fat (mean 930 microg kg(-1) fat). The calculated bound 3-MCPD content of these samples was within the range of 6 and 19 microg kg(-1) milk (mean of 12 microg kg(-1) milk). The major types of 3-MCPD esters were the symmetric diesters with lauric, palmitic, and oleic acids, and asymmetric diesters with palmitic acid/oleic acid among which 3-chloro-1,2-propanediol 1,2-dioleate prevailed. PMID:18484295

Zelinkov, Z; Novotn, O; Sch?rek, J; Velsek, J; Hajslov, J; Dolezal, M

2008-06-01

444

Preparation of silicate tungsten bronzes on aluminum by plasma electrolytic oxidation process in 12-tungstosilicic acid  

NASA Astrophysics Data System (ADS)

Percentage of oxide coatings area covered by active discharge sites decreases with time. Spatial density of microdischarges is the highest in the early stage of PEO process. Oxide coating is partly crystallized and mainly composed of ?-Al 2 O 3 and WO 3 . Outer layer of the coating is silicate tungsten bronze.

Petkovi?, M.; Stojadinovi?, S.; Vasili?, R.; Bel?a, I.; Nedi?, Z.; Kasalica, B.; Mio?, U. B.

2011-09-01

445

Conversion of beet molasses and cheese whey into fatty acid methyl esters by the yeast Cryptococcus curvatus.  

PubMed

Eighty-one yeast isolates from raw milk were surveyed for the production of fatty acid methyl esters (FAME). Only one species, identified as Cryptococcus curvatus, produced FAME at a detectable level. Cr. curvatus TYC-19 produced more FAME from beet molasses and cheese whey medium than other strains of the same species. In both media, the major FAME produced were linoleic and oleic acid methyl esters. Sequence analysis of the internal transcribed spacer region of ribosomal DNA indicated that TYC-19 diverged from the same species. PMID:20431242

Takakuwa, Naoya; Saito, Katsuichi

2010-01-01

446

A new class of potential anti-tuberculosis agents: Synthesis and preliminary evaluation of novel acrylic acid ethyl ester derivatives.  

PubMed

Novel acrylic acid ethyl ester derivatives were synthesized and evaluated as potential agents against Mycobacterium species. A versatile and efficient copper-catalyzed coupling process was developed and used to prepare a library of substituted acrylic acid ethyl ester analogs. Minimum inhibitory concentration assays indicated that two of these compounds 3 and 4 have greater in vitro activity against Mycobacterium smegmatis than rifampin, one of the current, first-line anti-mycobacterial chemotherapeutic agents. Moreover, members of this new class of compounds appear to exhibit a specific anti-mycobacterial effect and do not inhibit the growth of the other Gram-positive or Gram-negative species tested. PMID:20537903

Kabir, M Shahjahan; Namjoshi, Ojas A; Verma, Ranjit; Polanowski, Rebecca; Krueger, Sarah M; Sherman, David; Rott, Marc A; Schwan, William R; Monte, Aaron; Cook, James M

2010-05-07

447

Interactions between ?-tocopherol and rosmarinic acid and its alkyl esters in emulsions: synergistic, additive, or antagonistic effect?  

PubMed

Many antioxidants can interact to produce synergistic interactions that can more effectively inhibit lipid oxidation in foods. Esterification of rosmarinic acid produces a variety of compounds with different antioxidant activity due to differences in polarity and thus differences in partitioning in oil, water, and interfacial regions of oil-in-water emulsions (O/W). Therefore, rosmarinic acid and rosmarinate esters provide an interesting tool to study the ability of antioxidant to interact in O/W emulsions. In O/W emulsions, rosmarinic acid (R0) exhibited the strongest synergistic interaction with ?-tocopherol while butyl (R4) and dodecyl (R12) rosmarinate esters exhibited small synergistic interaction and eicosyl rosmarinate esters (R20) exhibited slightly antagonistic interaction. Fluorescence quenching and electron paramagnetic resonance (EPR) studies showed that water-soluble rosmarinic acid (R0) exhibited more interactions with ?-tocopherol than any of the tested esters (R4, R12, R20). This was also confirmed in O/W emulsions where R0 altered the formation of ?-tocopherol quinone and ?-tocopherol increased the formation of caffeic acid from R0. This formation of caffeic acid was proposed to be responsible for the synergistic activity of R0 and ?-tocopherol since the formation of an additional antioxidant could further increase the oxidative stability of the emulsion. PMID:22988974

Panya, Atikorn; Kittipongpittaya, Ketinun; Laguerre, Mickal; Bayrasy, Christelle; Lecomte, Jrme; Villeneuve, Pierre; McClements, D Julian; Decker, Eric A

2012-10-04

448

Identification of amino acid residues responsible for the release of free drug from an antibody-drug conjugate utilizing lysine-succinimidyl ester chemistry.  

PubMed

Unexpected release of free drug was observed during the stability testing of an antibody-drug conjugate (ADC). The ADC was designed to use lysine-succinimidyl ester chemistry to conjugate small molecule cytotoxic drugs to the antibody. To elucidate the mechanism of the release of free drug, a succinimidyl ester analog, 7-hydroxy-4-methyl-3-coumarinylacetic acid N-succinimidyl ester, and a series of peptides were used to probe the potential side reaction of succinimidyl ester with other amino acid residues. Cysteine and tyrosine residues were found to be reactive to succinimidyl ester, and the bonds formed through these reactions were found to be labile. Combining the fluorescent property of the succinimidyl ester analog and mass spectroscopy analysis, specific cysteine and tyrosine residues of the antibody were found to be reactive to succinimidyl ester and the bonds formed through this reaction were susceptible to hydrolysis. PMID:21294129

Chih, Hung-Wei; Gikanga, Benson; Yang, Yi; Zhang, Boyan

2011-02-03

449

Effects of dietary saturated and trans fatty acids on cholesteryl ester synthesis and hydrolysis in the testes of rats.  

PubMed

Studies were made of the enzymic synthesis and hydrolysis of cholesteryl esters in rat testes. Weanling rats were fed for 14 weeks diets containing 5% by wt of hydrogenated coconut oil (HCO), a concentrate of ethyl elaidate and linolelaidate (TRANS), devoid of essential fatty acids (EFA), or safflower oil (SAFF). Cholesterol esterifying activity was localized in the soluble fraction, and cholesteryl ester hydrolase activity was distributed in both particulate and soluble fractions obtained from tissue homogenates. The optimum pH was 6.0 for esterification and 6.9-7.0 for hydrolysis. Neither esterifying nor hydrolytic activity was affected by freezing and thawing, but both reactions were inhibited by heat or sonication. The animals of both the HCO and TRANS groups had developed an EFA deficiency before they were sacrificed. The EFA deficiency produced upon feeding the HCO diet had no apparent effect on the synthesis and hydrolysis of cholesteryl esters in rat testes. The TRANS diet influenced the development of the testes as judged by their size, and cholesterol esterifying and cholesteryl ester hydrolyzing activities were suppressed in the testes of the animals of this group. A major difference in the effects of the HCO and TRANS diets on the lipids of the tests was the relatively minor amount of eicosatrienoic acid (20:3) and the elevated level of docosapentaenoic acid (22:5) in the cholesteryl esters of the testicular lipids of the TRANS group. PMID:5644

Takatori, T; Phillips, F; Privett, O S

1976-05-01

450

Application of specific response factors in the gas chromatographic analysis of methyl esters of fatty acids with flame ionization detectors  

Microsoft Academic Search

The relative responses for flame ionization detectors in the analysis of the longer chain fatty acid methyl esters are shown\\u000a to correlate with the theoretical responses based on weight percent content of active carbon. While particularly affecting\\u000a estimation of the shorter chain length saturated fatty acids, these corrections have a less marked effect on the estimation\\u000a of unsaturated fatty acids.

R. G. Ackman; J. C. Sipos

1964-01-01

451

Comparative Subchronic and Chronic Dietary Toxicity Studies on 2,4-Dichlorophenoxyacetic Acid, Amine, and Ester in the Dog  

Microsoft Academic Search

Forms of 2,4-dichlorophenoxyacetic acid (2,4-D) are herbicides used in the control of a wide variety of broadleaf and woody plants. Subchronic toxicity studies in dogs were conducted on three forms of 2,4-D: the parent form, 2,4-D acid (ACID); 2,4-D dimethylamine salt (DMA); and 2,4-D 2-ethylhexyl ester (2-EHE). The three studies were designed to allow for comparison of the toxicity of

Jeffrey M. Charles; Dan W. Dalgard; Helen C. Cunny; Ronald D. Wilson; James S. Bus

1996-01-01

452

Magnesium Silicate  

Microsoft Academic Search

A comprehensive profile of magnesium silicate with 80 references is reported. A full description including nomenclature, formulae, and appearance is included. Methods for magnesium silicate preparation including precipitation, hydrothermal precipitation, and mechanochemical dehydration are reviewed. Physical characteristics, compendia and non-compendia analytical methods, uses, stability and incompatibilities, biodegradability, toxicity, and substances related to magnesium silicate are also discussed.

Iyad Rashid; Nidal H. Daraghmeh; Mahmoud M. Al Omari; Babur Z. Chowdhry; Stephen A. Leharne; Hamdallah A. Hodali; Adnan A. Badwan

2011-01-01

453

Magnesium silicate.  

PubMed

A comprehensive profile of magnesium silicate with 80 references is reported. A full description including nomenclature, formulae, and appearance is included. Methods for magnesium silicate preparation including precipitation, hydrothermal precipitation, and mechanochemical dehydration are reviewed. Physical characteristics, compendia and non-compendia analytical methods, uses, stability and incompatibilities, biodegradability, toxicity, and substances related to magnesium silicate are also discussed. PMID:22469264

Rashid, Iyad; Daraghmeh, Nidal H; Al Omari, Mahmoud M; Chowdhry, Babur Z; Leharne, Stephen A; Hodali, Hamdallah A; Badwan, Adnan A

2011-06-23

454

Use of chiral amino acid ester-based ionic liquids as chiral selectors in CE.  

PubMed

In this study, the applicability of a chiral ionic liquid (CIL) as the sole chiral selector in CE was investigated for the first time. In particular, five amino acid ester-based CILs were synthesized and used as additives in the BGE in order to evaluate their chiral recognition ability. The performance of these CILs as the sole chiral selectors was evaluated by using 1,1'-binaphthyl-2,2-diylhydrogenphosphate (BNP) as the analyte and by comparing the resolution values. Different parameters were examined, such as the alkyl group bulkiness and the configuration of the cation, the anion type of the CIL and its concentration, and the pH of the BGE, in order to optimize the separation of the enantiomers and to demonstrate the effect that each parameter has on the chiral-recognition ability of the CIL. Baseline separation of BNP within 13 min was achieved by using a BGE of 100 mM Tris/10 mM sodium tetraboratedecahydrate (pH 8) and a chiral selector of 60 mM l-alanine tert butyl ester lactate. The run-to-run and batch-to-batch reproducibilities were also evaluated by computing the %RSD values of the EOF and the two enantiomer peaks. In both cases, very good reproducibilities were observed, since all %RSD values were below 1%. PMID:23208781

Stavrou, Ioannis J; Kapnissi-Christodoulou, Constantina P

2013-02-01

455

40 CFR 721.10448 - Acetic acid, hydroxy- methoxy-, methyl ester, reaction products with substituted alkylamine...  

Code of Federal Regulations, 2013 CFR

...New Uses for Specific Chemical Substances § 721...methoxy-, methyl ester, reaction products with substituted...generic). (a) Chemical substance and significant...reporting. (1) The chemical substance identified...hydroxymethoxy-, methyl ester, reaction products with...

2013-07-01

456

Separation and purification of the antioxidant compounds, caffeic acid phenethyl ester and caffeic acid from mushrooms by molecularly imprinted polymer.  

PubMed

Caffeic acid phenethyl ester (CAPE) and caffeic acid (CA), two naturally occurring phenolic antioxidants, have been reported to have a diversity of biological activities. In this investigation, a novel approach to separate and enrich CAPE and CA from 25 species of mushrooms using molecularly imprinted polymers (MIPs) as the sorbent material is reported. The MIPs were synthesized using CAPE as the template, and its adsorption behavior was investigated in detail. In comparison with C18-solid phase extraction (SPE), MIP-SPE displayed high selectivity and good affinity for CAPE and CA. The antioxidant potential of the mushroom extracts, before and after preconcentration using MIPs, was assayed by inhibition of erythrocyte hemolysis and lipid peroxidation. Application of MIPs with a high affinity toward CAPE and CA provides a novel method for obtaining active compounds from natural products. PMID:23561222

Li, Ning; Ng, Tzi Bun; Wong, Jack Ho; Qiao, Ji Xuan; Zhang, Ye Ni; Zhou, Rong; Chen, Rong Rong; Liu, Fang

2013-02-09

457

Synthesis and antimicrobial activity of new (4,4,4-trihalo-3-oxo-but-1-enyl)-carbamic acid ethyl esters, (4,4,4-trihalo-3-hydroxy-butyl)-carbamic acid ethyl esters, and 2-oxo-6-trihalomethyl-[1,3]oxazinane-3-carboxylic acid ethyl esters  

Microsoft Academic Search

This work presents a three-step synthesis of a new series of 4-substituted 2-oxo-6-trihalomethyl-[1,3]oxazinane-3-carboxylic acid ethyl esters, from ?-alkoxyvinyl trihalomethyl ketones of general formula X3CC(O)CHC(R)OR1, where R=H, Me, Ph, and 4-Me-Ph; R1=Me and Et; and X=F and Cl. The Michael additionsubstitution of the ethyl carbamate on ?-alkoxyvinyl trihalomethyl ketones furnished the corresponding (4,4,4-trihalo-3-oxo-but-1-enyl)-carbamic acid ethyl esters. These compounds underwent reduction with

Nilo Zanatta; Deise M. Borchhardt; Sydney H. Alves; Helena S. Coelho; Adriana M. C. Squizani; Tiago M. Marchi; Helio G. Bonacorso; Marcos A. P. Martins

2006-01-01

458

Comparative toxicity of the diarrhetic shellfish poisons, okadaic acid, okadaic acid diol-ester and dinophysistoxin-4, to the diatom Thalassiosira weissflogii.  

PubMed

Quantitative structure-activity relationships were determined for the diarrhetic shellfish poisoning (DSP) toxins, okadaic acid (OA), OA diol-ester and dinophysistoxin-4 (DTX-4), using a sensitive bioassay procedure with the diatom Thalassiosira weissflogii. OA diol-ester was found to be nearly as toxic as OA. This result contradicted the accepted idea that only the free acid toxins, such as DTX-1 and OA, are potent phosphatase inhibitors. Postassay analyses using liquid chromatography-mass spectrometry (LC-MS) of cultures incubated with OA diol-ester showed that the ester had partially decomposed to OA, which explained some but not all of the observed toxicity. The formation of OA during the bioassay raised the possibility that cells exposed to inactive DSP toxin esters could metabolically activate them. This was examined in an additional experiment which showed that the hydrolysis of both DTX-4 and OA diol-ester was spontaneous and apparently not mediated by the presence of T. weissflogii cells. However, cells of T. weissflogii challenged with OA diol-ester rapidly metabolized most of the toxin to a more water-soluble product. From interpretation of mass spectral data obtained using ion-spray LC-MS, the metabolite was identified as an oxygenated diol-ester of OA, implying that it was the product of a monooxygenase-detoxification pathway. It is postulated that OA diol-ester, as a lipid-soluble, uncharged molecule with a propensity to hydrolyse to OA, may facilitate the transfer of OA across cell walls and membranes. PMID:9428106

Windust, A J; Quilliam, M A; Wright, J L; McLachlan, J L

1997-11-01

459

Melanogenesis-inhibitory saccharide fatty acid esters and other constituents of the fruits of Morinda citrifolia (noni).  

PubMed

Five new saccharide fatty acid esters, named nonioside P (3), nonioside Q (4), nonioside R (8), nonioside S (10), and nonioside T (14), and one new succinic acid ester, butyl 2-hydroxysuccinate (=4-butoxy-3-hydroxy-4-oxobutanoic acid) (31), were isolated, along with 26?known compounds, including eight saccharide fatty acid esters, 1, 2, 5, 6, 7, 9, 12, and 13, three hemiterpene glycosides, 15, 17, and 18, six iridoid glycosides, 21-25, and 27, and nine other compounds, 20, 28, 29, and 32-37, from a MeOH extract of the fruit of Morinda citrifolia (noni). Upon evaluation of these and five other glycosidic compounds, 11, 16, 19, 26, and 30, from M. citrifolia fruit extract for their inhibitory activities against melanogenesis in B16 melanoma cells induced with ?-melanocyte-stimulating hormone (?-MSH), most of the saccharide fatty acid esters, hemiterpene glycosides, and iridoid glycosides showed inhibitory effects with no or almost no toxicity to the cells. These compounds were further evaluated with respect to their cytotoxic activities against two human cancer cell lines (HL-60 and AZ521) and their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced with 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. PMID:22700235

Akihisa, Toshihiro; Tochizawa, Shun; Takahashi, Nami; Yamamoto, Ayako; Zhang, Jie; Kikuchi, Takashi; Fukatsu, Makoto; Tokuda, Harukuni; Suzuki, Nobutaka

2012-06-01

460

Soybean biodiesel methyl esters, free glycerin and acid number quantification by 1H nuclear magnetic resonance spectroscopy.  

PubMed

Production of alternative fuels, such as biodiesel, from transesterification of vegetable oil driven by heterogeneous catalysts is a promising alternative to fossil diesel. However, achieving a successful substitution for a new renewable fuel depends on several quality parameters. (1)H NMR spectroscopy was used to determine the amount of methyl esters, free glycerin and acid number in the transesterification of soybean oil with methanol in the presence of hydrotalcite-type catalyst to produce biodiesel. Reaction parameters, such as temperature and time, were used to evaluate soybean oil methyl esters rate conversion. Temperatures of 100 to 180 C and times of 20 to 240 min were tested on a 1 : 12 molar ratio soybean oil/methanol reaction. At 180 C/240 min conditions, a rate of 94.5 wt% of methyl esters was obtained, where free glycerin and free fatty acids were not detected. PMID:23225640

Coral, Natasha; Rodrigues, Elizabeth; Rumjanek, Victor; Zamian, Jos Roberto; da Rocha Filho, Geraldo Narciso; da Costa, Carlos Emmerson Ferreira

2012-12-07

461

First confirmation of human diarrhoeic poisonings by okadaic acid esters after ingestion of razor clams ( Solen marginatus) and green crabs ( Carcinus maenas) in Aveiro lagoon, Portugal and detection of okadaic acid esters in phytoplankton  

Microsoft Academic Search

A new outbreak of human diarrhoeic poisonings (DSP) with esters of okadaic acid (OA) was confirmed after ingestion of razor clams (Solen marginatus) harvested at Aveiro lagoon (NW Portugal) in the summer of 2001. Accumulation of marine toxins in second order consumers was investigated in the edible parts of a shellfish predator abundant at Aveiro lagoon, the green crab Carcinus

Paulo Vale; Maria Antnia de M. Sampayo

2002-01-01

462

Effects of sucrose fatty acid ester and blends on alveograph characteristics of wheat flour doughs  

Microsoft Academic Search

The effects of commercial sucrose ester emulsifiers (Ryoto, Mitsubishi-Kasei Food Corporation, Tokyo, Japan) on alveograph rheological dough properties of a commercial hard red winter (HRW) wheat flour were determined. The esters were evaluated alone or combined to produce blends of varying hydrophile-lipophile balance (HLB). In general, Alveograph dough rheological properties improved as HLB value of the sucrose ester increased. A

K Addo; M Slepak; C. C Akoh

1995-01-01

463

Prescription omega-3-acid ethyl esters for the treatment of very high triglycerides.  

PubMed

Triglyceride (TG) levels can increase for numerous reasons, including a sedentary lifestyle, an unhealthy diet, especially one rich in refined carbohydrates, and comorbidities. According to the National Cholesterol Education Program (NCEP), the normal TG level is < 150 mg/dL. Patients with very high TG (VHTG) levels (> or = 500 mg/dL) should be promptly managed and treated to reach lipid treatment goals, as determined by the NCEP. Lowering TG levels is the primary management goal in these patients, while lowering low-density lipoprotein cholesterol and non-high-density lipoprotein cholesterol levels are secondary goals. Therapeutic lifestyle changes are often recommended initially for patients with elevated TGs; however, concomitant drug therapy is often required. Data show that intake of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can significantly decrease serum TGs, along with plasma concentrations of certain lipoproteins. Omega-3-acid ethyl esters are available by prescription or as dietary supplements. Clinical trials in adult patients with VHTGs show that four 1 g capsules of prescription omega-3 fatty acids, which contain 465 mg of EPA and 375 mg of DHA per capsule, can effectively decrease TG levels by up to 45%, and is generally well tolerated. PMID:19641280

Sadovsky, Richard; Kris-Etherton, Penny

2009-07-01

464

40 CFR 721.8350 - 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester.  

Code of Federal Regulations, 2010 CFR

...2010-07-01 2010-07-01 false 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester. 721.8350...Chemical Substances § 721.8350 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester....

2010-07-01

465

40 CFR 721.8350 - 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester.  

Code of Federal Regulations, 2010 CFR

...2009-07-01 2009-07-01 false 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester. 721.8350...Chemical Substances § 721.8350 2-Propenoic acid, 7-oxa-bi-cy-clo[4.1.0]hept-3-ylmethyl ester....

2009-07-01

466

Effects of L-Carnitine on the Formation of Fatty Acid Ethyl Esters in Brain and Peripheral Organs after Short-Term Ethanol Administration in Rat  

Microsoft Academic Search

A study was undertaken in rats to evaluate the effects of short-term oral ethanol administration on the levels of fatty acid ethyl esters (FAEE) in brain and peripheral organs in the presence and absence of pretreatment with L-carnitine. Administration of ethanol to rats for seven days resulted in fatty acid ethyl ester formation, particularly in the heart and brain, but

V. Calabrese; V. Rizza

1999-01-01

467

40 CFR 721.1730 - Poly(oxy-1,2-ethanediyl), α-butyl--hydroxy, ester with boric acid (H3BO3).  

Code of Federal Regulations, 2010 CFR

...2-ethanediyl), ±-butyl--hydroxy, ester with boric acid (H3BO3). 721.1730 Section 721.1730 Protection of Environment...2-ethanediyl), α-butyl--hydroxy, ester with boric acid (H3BO3). (a) Chemical substance and significant new uses...

2009-07-01

468

40 CFR 721.1730 - Poly(oxy-1,2-ethanediyl), α-butyl--hydroxy, ester with boric acid (H3BO3).  

Code of Federal Regulations, 2010 CFR

...2-ethanediyl), ±-butyl--hydroxy, ester with boric acid (H3BO3). 721.1730 Section 721.1730 Protection of Environment...2-ethanediyl), α-butyl--hydroxy, ester with boric acid (H3BO3). (a) Chemical substance and significant new uses...

2010-07-01

469

40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl--hydroxy, ester with boric acid (H3BO3).  

Code of Federal Regulations, 2010 CFR

...2-ethanediyl), ±-methyl--hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment...2-ethanediyl), α-methyl--hydroxy, ester with boric acid (H3BO3). (a) Chemical substance and significant new uses...

2009-07-01

470

40 CFR 721.1731 - Poly(oxy-1,2-ethanediyl), α-methyl--hydroxy, ester with boric acid (H3BO3).  

Code of Federal Regulations, 2010 CFR

...2-ethanediyl), ±-methyl--hydroxy, ester with boric acid (H3BO3). 721.1731 Section 721.1731 Protection of Environment...2-ethanediyl), α-methyl--hydroxy, ester with boric acid (H3BO3). (a) Chemical substance and significant new uses...

2010-07-01

471

40 CFR 721.5375 - Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis-[[[[(sub-sti-tut-ed)] amino]-alkyl-phenyl...  

Code of Federal Regulations, 2010 CFR

...Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis-[[[[(sub-sti-tut-ed)] amino]-alkyl-phenyl]-az-o] (ge-ner-ic...Ni-tro-thio-phene-car-boxy-lic acid, ethyl es-ter, bis-[[[[(sub-sti-tut-ed)] amino]-alkyl-phenyl]-az-o]...

2010-07-01

472

Antifeedant activity of fatty acid esters and phytosterols from Echium wildpretii.  

PubMed

Crude extracts and fractions from Echium wildpretii H. Pearson ex Hook. f. subsp. wildpretii (Boraginaceae) have been tested against insect species Spodoptera littoralis, Leptinotarsa decemlineata, and the aphids Myzus persicae, Diuraphis noxia, Metopolophium dirhodum, Rhopalosiphum maidis, and Rhopalosiphum padi. The EtOH extract and the lipid and steroidal fractions of E. wildpretii exhibited significant antifeedant activities against the aphids and L. decemlineata. Two bioactive mixtures composed of fatty acid esters and n-alkanes were obtained from the lipid fraction. The bioguided fractionation of the steroidal fraction resulted in the isolation of glutinol, ?-sitosterol, (3?,7?)-stigmast-5-ene-3,7-diol, and (3?,7?)-7-methoxystigmast-5-en-3-ol. The latter two compounds exhibited potent antifeedant activities against L. decemlineata indicating that the presence of an O-bearing C(7) was responsible for the activities of these molecules. PMID:22422524

Santana, Omar; Reina, Matias; Fraga, Braulio M; Sanz, Jess; Gonzlez-Coloma, Azucena

2012-03-01

473

Biodegradable coumaric acid-based poly(anhydride-ester) synthesis and subsequent controlled release.  

PubMed

To overcome drug delivery issues associated with its short half-life in vivo,p-coumaric acid (pCA), a naturally occurring bioactive, has been chemically incorporated into a poly(anhydride-ester) backbone through solution polymerization. Nuclear magnetic resonance and Fourier transform infrared spectroscopies indicated that pCA was successfully incorporated without noticeable alterations in structural integrity. The polymer's weight-average molecular weight and thermal properties were determined, exhibiting a molecular weight of over 26 000 Da and a glass transition temperature of 57 C. In addition, in vitro hydrolytic release studies demonstrated pCA release over 30 d with maintained antioxidant activity, demonstrating the polymer's potential as a controlled release system. PMID:23836606

Ouimet, Michelle A; Stebbins, Nicholas D; Uhrich, Kathryn E

2013-07-09

474

Functionalization of quartz crystal microbalances with liposomes containing the N-hydroxysuccinimide ester of palmitic acid.  

PubMed

We developed a fast and simple method to functionalize a quartz crystal microbalance (QCM) with liposomes composed of phosphatidylcholine lipid and the N-hydroxysuccinimide (NHS) ester of palmitic acid. The liposome was applied directly to a bare gold surface of a QCM to prepare the lipid bilayer presenting NHS groups on the surface. The whole functionalization process was completed within 1h using stored lipid films. Streptavidin immobilization efficiency of the method was comparable to the 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/NHS chemical method, and the activity of the biotinylated antibody immobilized through the streptavidin was stably retained in repeated surface regeneration with the dissociation buffer. PMID:23993905

Eom, Sora; Yu, Eunkyeong; Choi, Suk-Jung

2013-08-28

475

Polar and aliphatic domains regulate sorption of phthalic acid esters (PAEs) to biochars.  

PubMed

Molecular variations among different biochar categories translate into differences in their ability to function as sorbents to three phthalic acid esters (PAEs) representing a gradient in hydrophobicity. The sorption capacity (K(OC)) for all three PAEs was the greatest for amorphous biochars (heat treatment temperature HTT=400 C), followed by biochars produced at 300 C, and was best explained by the hydrophobicity of the sorbate. Greater alkyl C content and higher polarity of grass chars versus wood chars prepared at similar temperatures explained both (a) the difference in sorbent strength between feedstocks and (b) the maximum in sorbent strength at relatively low HTTs (300-400 C). Hydrophobic partitioning into 'soft' alkyl carbon and specific H-bonding involving char-bound O and N groups jointly account for high affinities of PAEs for low-HTT biochars. The results highlight the influence of feedstocks and HTTs on PAEs sorption strength and mechanism. PMID:22705514

Sun, Ke; Jin, Jie; Keiluweit, Marco; Kleber, Markus; Wang, Ziying; Pan, Zezhen; Xing, Baoshan

2012-05-11

476

Chronic toxicity and carcinogenicity of sucrose fatty acid esters in Fischer 344/DuCrj rats.  

PubMed

A 13-week and a 2-year feeding study were conducted in Fischer 344/DuCrj rats to evaluate the oral toxicity and carcinogenicity of S-570, a mixture of mono-, di-, tri-, and higher esters of sucrose with fatty acids derived from edible fats and oils. In both studies, S-570 was fed at 0, 1, 3, or 5% (w/w) of the diet to groups of 20 male and 20 female rats in the 13-week study and 50 male and 50 female rats in the carcinogenicity study. Animals in satellite groups of 14 rats/sex/group were sacrificed at 12 months to evaluate chronic toxicity. There were no S-570-related effects on survival, tumor incidence or time to tumor, ophthalmology, hematology, clinical chemistry, organ weights, or histopathology. These results indicate that S-570 is not toxic or carcinogenic when fed to rats at up to 5% of the diet for 2 years. PMID:12052001

Takeda, K; Flood, M

2002-04-01

477

L-methionine methyl ester hydrochloride as a corrosion inhibitor of iron in acid chloride solution  

SciTech Connect

Some aminoester organic compounds were tested as corrosion inhibitors for iron in molar hydrochloric acid (HCl) by mass-loss and electrochemical polarization methods. Both techniques gave the same order of inhibition. Comparison of results among those aminoesters showed L-methionine methyl ester (METOCH{sub 3}) was the best inhibitor. Its inhibition efficiency (E%) reached a maximum value of 95% at 10{sup {minus}2} M. Polarization measurements indicated METOCH{sub 3} acted as a cathodic inhibitor without changing the mechanism of the hydrogen evolution reaction. METOCH{sub 3} was adsorbed on the iron surface according to a Frumkin isotherm model. The effect of temperature indicated that E% of METOCH{sub 3} increased with increasing temperature in the range of 20 C to 50 C.

Hammouti, B.; Aouniti, A.; Taleb, M.; Brighli, M. [Faculte des Sciences Oujda (Morocco). Lab. de Chimie Analytique Appliquee; Kertit, S. [Ecole Normale Superieure de Takaddoum, Rabat (Morocco). Lab. de Physico-Chimie des Materiaux

1995-06-01

478

Fumaric acid and its esters: an emerging treatment for multiple sclerosis with antioxidative mechanism of action.  

PubMed

Fumaric acid was originally therapeutically used in psoriasis. Several lines of evidence have demonstrated immunomodulatory but also neuroprotective effects for FAE. Clinical studies in psoriasis showed a reduction of peripheral CD4+ and CD8+ T-lymphocytes due to the ability of FAE to induce apoptosis. In vitro studies with the ester dimethylfumarate (DMF) described an inhibitory effect on nuclear factor kappa B (NF-?B)-dependent transcription of tumor necrosis factor-alpha (TNF-?) induced genes in human endothelial cells. Animal experiments in the mouse model of central nervous system demyelination, MOG-induced experimental autoimmune encephalomyelitis, revealed a clear preservation of myelin and axonal density in the plaque. Molecular studies showed that this is based on the antioxidative mechanism of action via induction of the transcription factor Nrf-2. A phase II clinical trial in relapsing-remitting multiple sclerosis (RRMS) patients with dimethylfumarate showed a significant reduction in the number of gadolinium enhancing lesions after 24weeks. PMID:21414846

Gold, R; Linker, R A; Stangel, M

2011-02-26

479

Synthesis of carboxylic acids, esters, alcohols and ethers containing a tetrahydropyran ring derived from 6-methyl-5-hepten-2-one.  

PubMed

3-hydroxy acids, 3-hydroxy-3,7-dimethyloct-6-enoic acid (1) and 3-hydroxy-2,2,3,7-tetramethyloct-6-enoic acid (2), were prepared from 6-methyl-5-hepten-2-one, and they were subsequently used to prepare (2,6,6-trimethyltetrahydropyran-2-yl)acetic acid (3) and 2-methyl-2-(2,6,6-trimethyltetrahydropyran-2-yl)propanoic acid (4), respectively, via cyclization with an acidic catalyst such as boron trifluoride diethyl etherate or iodine. The reaction of carboxylic acids 3 and 4 with alcohols, including methanol, ethanol, and 1-propanol, produced the corresponding methyl, ethyl, and propyl esters, which all contained a tetrahydropyran ring. Reduction of carboxylic acids 3 and 4 afforded the corresponding alcohols. Subsequent reactions of these alcohols with several acyl chlorides produced novel esters. The alcohols also reacted with methyl iodide and sodium hydride to provide novel ethers. A one-pot cyclization-esterification of 1 to produce esters containing a tetrahydropyran ring, using iodine as a catalyst, was also investigated. PMID:23138252</