Branched-chain Compounds Research Articles

Glycolipids from some extreme thermophilic bacteria belonging to the genus Thermus.

The lipids of Thermus aquaticus YT1, Thermus thermophilus HB8, Thermus sp. strains H and J (from Icelandic hot springs), and Thermus sp. strain NH (from domestic hot water) have been investigated. Each strain contained two major components, a glycolipid and a glycophospholipid, which have been isolated and analyzed. All of the strains contained as the principal component (41 to 57% of total lipid) a diacyldiglycosyl-(N-acyl)glycosaminylglucosylglycerol, but the five glycolipids differed in carbohydrate composition. The glycophospholipid appeared to be identical in each strain and contained an N-acylglucosamine residue. The principal fatty acids were C15 and C17 branched-chain compounds. This unique polar lipid composition should be of value in the classification of other thermophiles in the genus Thermus. The exceptionally high carbohydrate content of the lipids of these extreme thermophiles may be of significance in relation to the molecular basis of thermophily.

OIL-DEGRADING POTENTIAL OF SURFICIAL SEDIMENTS NEAR OIL-PRODUCING PLATFORMS

ABSTRACT All surficial sediment samples were obtained either from areas near oil production platforms or from control areas some distance from these platforms during three separate cruises. All samples contained organisms capable of degrading crude oil in laboratory microcosm studies. Under conditions designed to test oil-degrading potential in situ, rate of degradation was not appreciably influenced by temperature fluctuations within a range of 15 to 27°C, or oil concentration, nor was it increased by added phosphorus or nitrogen. The maximum oil-degrading potential of the sediments was calculated to be 56 micrograms hydrocarbon carbon converted to carbon dioxide per milliliter of sediment per day. Oxygen diffusion into the sediments appeared to be the rate-limiting factor. Enrichment cultures prepared from platform sediments were more active than enrichment cultures prepared from control sediments. Studies with mixed and pure cultures revealed substrate preference for straight-chain hydrocarbons over the branched-chain compounds and aromatics. Some high molecular weight straight-chain aliphatics (about C30) and large amounts of branched-chain (C24 or C25) aliphatics were produced by some pure cultures isolated from sediment samples.

Recherches sur les substances mesomorphes—IX : Smectiques “fourchus”. organisation moleculaire dans les phases smectiques a

The synthesis and the mesomorphic properties of new branched smectogenic A derivatives of fluorene are described. The observation that branched chain compounds form a smectic A phase allows conclusions to be drawn on molecular arrangements in smectic A layers.

Calorimetric study of the enthalpies of solvation in cyclohexane and in water for homologous aliphatic ketones and esters

The standard enthalpies of solution at infinite dilution were determined for homologous aliphatic ketones and esters in water and in cyclohexane at 298.15 K, using a rotating Calvet calorimeter and solution concentrations about 5 × 10 −4 mole fraction. Vaporization enthalpies, obtained for each compound with an effusion calorimetric cell, were added to calculate the solvation enthalpies. For the n-substituted compounds the solvation enthalpies are linearly dependent on the number ( N) of carbon atoms for N > 2, giving the following values for the solvation of the methylene group. ▪ Extrapolation to N = 0 should give values related to the solvation enthalpies of the functional groups, but this is complicated because of the deviation from the linearity of the curves for N < 2. The observed deviations, greater for water, are connected with the ‘structural effect’ produced in the solvent by the functional groups. Comparisons are made between solvation enthalpies of n-ketones and n-esters with the corresponding values of branched or cyclic substitutes. In both solvents, all branched chain compounds show enthalpies of solvation that are less exothermic than for the normal isomers. On the other hand all the symmetrically substituted ketones show heavily increased solvation enthalpies in comparison with the corresponding methyl substituted compounds.

Effect of leucine and metabolites of branched chain amino acids on protein turnover in heart.

Leucine, but not isoleucine or valine, inhibited protein degradation and accelerated protein synthesis in hearts perfused with buffer that contained glucose (15 mM) and normal plasma levels of other amino acids, except for the branched chain compounds. Products of leucine, isoleucine, and valine metabolism also inhibited protein degradation and stimulated protein synthesis. These compounds included the transamination and decarboxylation products, as well as acetate, acetoacetate, and propionate. In some, but not all instances, inhibition of degradation and acceleration of synthesis were accompanied by an increase in intracellular leucine. When insulin was added to the perfusate, the rate of degradation was reduced by 40%, but addition of leucine was ineffective in the presence of the hormone. Insulin, leucine (2 mM) and a mixture of branched chain amino acids at normal plasma levels increased latency of cathepsin D in hearts that were perfused with buffer containing glucose. A combination of leucine and insulin increased latency more than either substance alone. These studies indicate that leucine as well as a variety of substrates that are oxidized in the citric acid cycle are involved in regulation of protein turnover in heart muscle.

ChemInform Abstract: STRUCTURES AND PROPERTIES OF MIXTURES OF BRANCHED CHAIN COMPOUNDS AND LECITHIN: PHYTOL, α‐TOCOPHEROL (VITAMIN E), AND PHYTANIC ACID

Chemischer InformationsdienstVolume 10, Issue 24 Article ChemInform Abstract: STRUCTURES AND PROPERTIES OF MIXTURES OF BRANCHED CHAIN COMPOUNDS AND LECITHIN: PHYTOL, α-TOCOPHEROL (VITAMIN E), AND PHYTANIC ACID R. J. CUSHLEY, R. J. CUSHLEYSearch for more papers by this authorB. J. FORREST, B. J. FORRESTSearch for more papers by this authorA. GILLIS, A. GILLISSearch for more papers by this authorJ. TRIBE, J. TRIBESearch for more papers by this author R. J. CUSHLEY, R. J. CUSHLEYSearch for more papers by this authorB. J. FORREST, B. J. FORRESTSearch for more papers by this authorA. GILLIS, A. GILLISSearch for more papers by this authorJ. TRIBE, J. TRIBESearch for more papers by this author First published: June 12, 1979 https://doi.org/10.1002/chin.197924080Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume10, Issue24June 12, 1979 RelatedInformation

Structures and properties of mixtures of branched chain compounds and lecithin: phytol, α-tocopherol (vitamin E), and phytanic acid

Phospholipid bilayers containing branched chain molecules, phytol (1), vitamin E (2), and phytanic acid (3), have been investigated by 31P nmr, esr, and differential scanning calorimetry (dsc).A 31P lanthanide induced shift study indicated varying permeabilities to Pr3+ in the order phytanic acid &gt; vitamin E &gt; phytol &gt; egg yolk lecithin alone; the half-lives (in days) were 0.002, 0.14, 0.83, and 6.5, respectively. The activation energy for Pr3+ permeation through the egg yolk lecithin–phytol membrane was found to be 84.9 ± 0.8 kJ.The following esr order parameters, S3, were obtained using the extrinsic spin label, 5-doxylpalmitic acid, in oriented mixed multibilayers: S3 (1) = 0.29, S3 (2) = 0.50, and S3 (3) = 0.02.Differential scanning calorimetry revealed a lowering of the gel–liquid crystalline phase transition temperature, Tc, as the concentration of incorporated isoprenoid compound increases, with eventual disappearance of the endotherm. Specific entropy, s, calculated for dipalmitoyl lecithin +25 mol% 3 is 126 J kg−1 K−1 compared to s = 114.2 J kg−1 K−1 for 1and s = 85 J kg−1 K−1 for 2.

Manufacturing Process of Activated Carbon fvom Asphalt (X)

Asphalt was treated with sulfonating reagent, using hydrocarbon oil as solvent, instead of such halogenated hydrocarbons as 1, 1, 2-trichloroethane, perchloroethylene, etc., which might have toxicity.Saturated aliphatic hydrocarbons were relatively stable to acids, pretreatment reagents of asphalt, therefore they could be used as solvent for asphalt.Granulated char was obtained in hydrocarbon solvents with carbon number above 7. The grain size of the granulated char became smaller with increasing carbon number of solvent molecule.The highest yield of granulated char was obtained in the case of noctane; its share was 90% of the total char produced.The solubility of asphalt to aliphatic hydrocarbons was better in normal chain compounds than in branched chain compounds, and the former was more stable to acid than the latter. The average recovery of n-paraffine (carbon number 7-9) was about 98%; this value was almost the same as that of 1, 1, 2-trichloroethane.Though the hardness of char varied according to the carbon number of solvent used, generally it was a little smaller than that of the char obtained with 1, 1, 2-trichloroethane.Comparing at the same yield of activated carbon, the specific surface area of activated carbon obtained with hydrocarbon solvent was more or less smaller than that with 1, 1, 2-trichloroethane. But these activated carbons showed almost the same methylene blue adsorbability.

Preparation of analogues of the carbohydrate moiety of the polyoxins.

Syntheses of 2-C-[ethoxycarbonyl(formylamino)methylene] carbohydrate derivates by formylaminomethylenation of two pentofuranosulosides and a pentopyranosuloside are described. Hydrogenation of the unsaturated branched-chain compounds gave glycosides bearing protected amino-acid moieties as substituents at C-2. Hydrolysis and reduction experiments that establish the structures of the branched-chain compounds are described.

Branched Long-chain Bases in Ceramide 2-Aminoethylphosphonate from Ova of the Fresh-water Bivalve, Hyriopsis schlegelii

In our previous communication the discovery of ceramide 2-aminoethylphosphonate (CAEP) in ova of a fresh-water bivalve, H. schlegelii was reported. The ova sphingolipid contained mostly 4-sphingenines which were composed of octadecasphingenine (predominant) and branched octadeca- and nonadecasphingenines. In this paper we wish to report on the characterization of the above branched compounds. A ceramide fraction derived by enzymatic degradation of CAEP was subjected to catalytic hydrogenation, hydrolyzed and separated into long-chain bases and fatty acids as described earlier. Thin-layer chromatogram of the hydrogenated long-chain bases revealed one major ninhydrin positive component with the same Rf value as that of authentic octadecasphinganine, with a very small amount of artifacts (O-methyl derivatives) (Fig. -1). The hydrogenated bases were oxidatively cleaved to aldehydes with lead tetra-acetate (this resulted in the loss of two carbon atoms from the parent carbon skeleton), and were analyzed by gas-liquid chromatography (GLC) using a 3m×3mm glass column containing 25% EGS on 6080 mesh Celite 545. Based on equivalent chain length data described by Morrison on straight and branched chain aldehydes, all of the aldehydes except Peak 3 in Fig. -2 were tentatively identified as iso-hexadecanal (Peak 1), n-hexadecanal (Peak 2), iso-heptadecanal (Peak 4) and anteiso-heptadecanal (Peak 5), respectively. For the further confirmation of the above branched chain compounds, the aldehydes were oxidized with silver oxide, and the resulting fatty acids after methylation were analyzed by GLC. Fatty acid methyl esters derived from the aldehydes of Peak 1, 2, 4 and 5 had identical retention times as iso-palmitic acid, palmitic acid, iso-margaric acid and anteiso-margaric acid (Fig. -4). However, Peak 3 in Fig. -4 did not correspond to any of the authentic saturated methyl esters available in the C14C17 range and no further characterization of this peak was made. From the gas chromatographic analyses of aldehydes and the corresponding fatty acid methyl esters, the composition of long-chain base mixtures in the ova CAEP was calculated and given as follows; iso-sphingosine (12%), sphingosine (60%), iso-nonadeca-4-sphingenine (2%), anteiso-nona-deca-4-sphingenine (22%) and unidentified long-chain base (4%). This is the first paper on the branched long-chain bases found in shellfish.

Chemical reactions at lipid‐gas interfaces: II. Insolubilizing reactions induced by an electrical discharge

AbstractReactions caused by corona discharges (passing through atmospheres of methane, hydrogen or argon) striking the surfaces of aqueous solutions containing long chain fatty acid salts resulted in the formation of solid and insoluble products. These results show that the fatty acid ions were oriented on the aqueous surfaces in such a way that the hydrocarbon chains projected out of the surfaces. Surface layers of long chain alcohols reacted similarly but short and branched chain compounds were not polymerized under the experimental conditions that were used. When methane or hydrogen was used as the discharge gas, reactions occurred along the hydrocarbon chains of the compounds so that the products consisted of networks of many short hydrocarbon chains. These reactions were probably caused by the penetration of hydrogen atoms into the surface layers. Joining of terminal methyl groups of the hydrocarbon chains was the main reaction observed when argon was used as the discharge gas.

Plant response to pesticides and environment: Sicklepod (Cassia tora L.) fatty acid separation by gas chromatography

AbstractFatty acid content of sicklepod (Cassia tora L.) leaves and stems was determined by GLC. Major constituents were identified as palmitate, stearate, oleate, linoleate and linolenate at 20.8%, 6.4%, 5.7%, 13.1% and 26.0%, respectively, of the total fatty acids present. The remainder of the fatty acids occurred in shorter or longer homologues and branched chain compounds. Chain lengths up to C34 were found.

Column chromatographic analysis of aminoalkylphosphonates

Conditions are described which permit simultaneous column chromatographic analysis of either aminomethylphosphonate or aminopropylphosphonate and nine other aminoalkylphosphonates. The two branched chain compounds were impure and interfered with several peaks. Methods are given to eliminate interferences by other acidic compounds except taurine. The method permits recognition of the AAP's in nature and allows their use as amino acid analogs.

Identification of fatty acids from butterfat using a combined gas chromatograph-mass spectrometer

SummaryThe identification and approximate quantitative determination of methyl esters of fatty acids from commercial butterfat was obtained with a combined gaschromatograph-mass spectrometer instrument. Fifty-two components, straight chain saturated and unsaturated, as well as branched chain compounds, were identified. Seven monomethyl saturated fatty acid methyl ester isomers were identified for both C15and C17, i.e. with chain lengths of 14 and 16 carbon atoms, respectively. Multibranched fatty acids with molecular weights of 326 and 368 were found. The results were obtained in one day.

Studies on the metabolic error in Refsum's disease.

Studies utilizing mevalonic acid-2-(14)C and D(2)O as precursors failed to provide evidence for an appreciable rate of endogenous biosynthesis of phytanic acid in a patient with Refsum's disease. Orally administered tracer doses of phytol-U-(14)C were well absorbed both by seven normal control subjects (61 to 94%) and by two patients with Refsum's disease (74 and 80%). The fraction of the absorbed dose converted to (14)CO(2) in 12 hours was 3.5 and 5.8% in Refsum's disease patients and averaged 20.9% in seven control subjects. Labeled phytanic acid was demonstrated in the plasma of both control subjects and patients given phytol-U-(14)C, establishing phytol in the diet as a potential precursor of phytanic acid. This labeled phytanic acid had disappeared almost completely from the plasma of the seven control subjects by 24 to 48 hours, whereas it persisted at high concentrations in the plasma of the two patients for many days. We conclude that the phytanic acid accumulating in Refsum's disease is primarily of exogenous origin and that patients with Refsum's disease have a relative block in the degradation of phytanic acid and possibly other similar branched-chain compounds. This may relate to a deficiency in mechanisms for release of phytanic acid from stored ester forms or, more probably, to reactions essential to oxidative degradation of the carbon skeleton.

VIGOROUS MOLD GROWTH IN SOILS AFTER ADDITION OF WATER-INSOLUBLE FATTY SUBSTANCES.

Various water-insoluble fatty compounds, when added to soil in finely divided form, will support as high-caloric nutrients a visible, vigorous growth of the molds, Fusarium solani Mart., F. diversisporum Sherb., and F. equiseti. n-Paraffins and olefins are most effective, because the effect of additives is reduced to the extent that oxygen atoms are introduced into the molecule. n-Fatty alcohols support growth in soil almost as well as the paraffins; however, growth is reduced when branched-chain compounds are added as nutrients. Compounds that will support mold growth when added to air-dried soil as finely powdered solids will not do so when incorporated at temperatures above their melting point, but will produce dense growth when applied to wet soil in this form. Mold growth is correlated with degradation of fatty matter. The rate of degradation is controlled by the availability of water, oxygen, and the basic inorganic nutrients.

Vigorous Mold Growth in Soils After Addition of Water-Insoluble Fatty Substances

Various water-insoluble fatty compounds, when added to soil in finely divided form, will support as high-caloric nutrients a visible, vigorous growth of the molds, Fusarium solani Mart., F. diversisporum Sherb., and F. equiseti. n-Paraffins and olefins are most effective, because the effect of additives is reduced to the extent that oxygen atoms are introduced into the molecule. n-Fatty alcohols support growth in soil almost as well as the paraffins; however, growth is reduced when branched-chain compounds are added as nutrients. Compounds that will support mold growth when added to air-dried soil as finely powdered solids will not do so when incorporated at temperatures above their melting point, but will produce dense growth when applied to wet soil in this form. Mold growth is correlated with degradation of fatty matter. The rate of degradation is controlled by the availability of water, oxygen, and the basic inorganic nutrients.

Composition of the unsaponifiable matter of vernix caseosa

Detailed examination of the unsaponifiable material from the skin wax of newly born babies has shown that the saturated aliphatic alcohols contain a high proportion of branched-chain compounds, and the aliphatic α,β-dials consist almost entirely of branched-chain compounds. The sterol fraction consists of cholesterol, and a minor amount of an unidentified sterol. The hydrocarbon fraction consists entirely of squalene.

Sodium dialkyl phosphates: Surfactant properties and use in heavy duty detergents

AbstractA study of the physical and surface active properties of the sodium salts of dialkyl phosphates has been made. These compounds have been evaluated for use as surfactants in built detergents and their performance has been compared with commercial surfactants.The dialkyl hydrogen phosphates contained from 16舑26 carbon atoms per molecule and were prepared from both straight chain alcohols and commercially available branched chain alcohols.In general, the surface active properties of the branched chain compounds are better than their corresponding straight chain compounds. Good detergency performance is obtained when the number of carbon atoms per molecule is between 17 and 23. Optimum performance is obtained with the symmetrical didecyl hydrogen phosphate salts made from commercial decyl alcohol produced by the oxo‐process.

Complexity of Hop Oil

PROGRESS in instrumental methods of analysis during the past 10 years, particularly in the new field of gas chromatography, has provided the chemist with powerful tools for the separation and identification of complex mixtures. Nevertheless, it is often advantageous to fractionate the mixture prior to gas chromatography analysis in order to simplify the task of isolation and identification of single components. The oil of the hop (Humulus lupulus L. var. Bullion) isolated by the method of Wright and Connery1 has been fractionated as follows: hydrocarbons were selectively separated from oxygenated compounds through alumina or silica-gel columns using light petroleum ether as eluant2. Esters and ketones were separated from alcohols by selective elution from a neutral alumina column using absolute ether as eluant. Esters were subjected to methanolysis using mineral acid as catalyst, and the resulting methyl esters separated from the freed alcohols, as described here. Compounds having a straight chain of seven carbons or more were separated from shorter or branched chain compounds by formation of crystalline adducts with urea in methanol3. Carbonyls were extracted from mixtures containing other oxygenated compounds by the Girard method4,5. Unsaturated compounds were separated from saturated compounds by bromination in carbon tetrachloride6. Unsaturated compounds having a conjugated double-bond system were separated from others by the Diels–Alder reaction7.