Hydrocarbon degradation by <Emphasis Type="Italic">Dietzia</Emphasis> sp. A14101 isolated from an oil reservoir model column

The hydrocarbon-degrading strain Dietzia sp. A14101 was isolated from an oil reservoir model column inoculated with oil-field bacteria. The column was continuously injected with nitrate (0.5 mM) from the start of water flooding, which lead to a gradual development of nitrate reduction in the column. Strain A14101 was able to utilize a range of aliphatic hydrocarbons as sole carbon and energy source during aerobic growth. Whole oil gas chromatography analysis of the crude oil phase from aerobic pure cultures showed that strain A14101 utilized the near complete range of aliphatic components and aromatic components toluene and xylene. Longer n-alkanes ≥C₁₇ were utilized simultaneously with the shorter C₁₀ and C₁₅. After 120 days aerobic incubation, the whole oil gas chromatography profile of the crude oil phase was similar to that of heavily biodegraded oils. Anaerobic degradation of hydrocarbons with nitrate was not observed. Nitrate reduction was, however, observed during anaerobic growth on propionate, which suggests that strain A14101 grows on fatty acids in the column rather than on hydrocarbons.     

Studies on the Changes of Meat Fats by Various Processings

Data are presented to show the gas chromatographic identification of a total of 18 saturated aliphatic γ- and δ-lactones obtained from melted beef depot fat, namely, δ-C₆, γ-C₇, γ-C₈, γ-C₉, and a homologous series of γ- and δ-lactones of the even-carbon numbers C₁₀ to C₁₆ and of smaller amount of the odd-carbon numbers C₁₁ to C₁₅. These lactones were isolated by steam distillation and silicic acid adsorption chromatography, and identified through gas chromatography and infrared spectroscopy.

Lactones obtained had a peach-like flavor, and it was suggested that lactones were important in heated beef fat as the flavor compounds.     

Enhanced thin-layer chromatographic separation of GM1b-type gangliosides by automated multiple development

Enhancement in separation of gangliosides on silica gel precoated high-performance TLC plates has been obtained by automated multiple development chromatography. A less polar mixture of the standard solvent chloroform-methanol-20 mM aqueous CaCl₂ (120:85:20, v/v) was used. Lowering the water content achieved separation of two complex monosialoganglioside fractions, isolated from murine YAC-1 T lymphoma and MDAY-D2 lymphoreticular cells. Three-fold chromatography in the solvent chloroform-methanol-20 mM aqueous CaCl₂ (120:85:14, v/v) resulted in TLC separation of G_M1b-type gangliosides, substituted with C₂₄ and C₁₆ fatty acids and with Neu5Ac and Neu5Gc as well, which could not be achieved by undirectional standard chromatography. Compared to conventional single chromatography, the technique described allows high-resolution separation of extremely heterogenous ganglioside mixtures and offers a convenient tool for both analytical and preparative TLC.     

Constituents of Fusel Oils Obtained Through the Fermentation of Corn,Barley and Sweet Molasses

The components of the fusel oils obtained through the fermentation of corn, barley and sweet molasses were separated by fractional distillation and adsorption chromatography. Each of the components was analyzed by gas chromatography and infrared spectrometry. Newly isolated components were as follows: methyl heptenone, fatty acids having odd number of carbon atoms, acetic esters of higher aliphatic alcohols ranging from C₆ to C₁₁, benzyl alcohol, ethyl phenylacetate, phenylethyl propionate, acetophenone, limonene, and α-ionone. Moreover, an unknown ketone C₁₀H₁₆O were isolated from corn fusel oil, and trans-neroridol from sweet molass fusel oil.     

OCCURRENCE OF ALKANES IN BRAIN MYELIN. COMPARISON BETWEEN NORMAL AND QUAKING MOUSE

Alkanes, a new class of neurolipid, were found in mouse brain, the level being reduced in the Quaking mutant. These hydrocarbons are concentrated in myelin; minor amounts being found in microsomes, mitochondria and synaptosomes. The average recovery is 7.1 μg/mg in normal myelin, 2.2 in the Quaking myelin. The distribution pattern of these alkanes was determined by gas liquid chromatography and was found to differ in normal and Quaking myelin; the hydrocarbons consist mainly of n-alkanes ranging from C₂₁ to C₃₂ with even and odd aliphatic chains.     

Biochemical characterization of Rhodococcus erythropolis N′4 nitrile hydratase acting on 4-chloro-3-hydroxybutyronitrile

The Rhodococcus erythropolis strain (N′4) possesses the ability to convert 4-chloro-3-hydroxybutyronitrile into the corresponding acid. This conversion was determined to be performed by its nitrile hydratase and amidase. Ammonium sulfate fractionation, DEAE ion exchange chromatography, and phenyl chromatography were used to partially purify nitrile hydratase from cell-free extract. A SDS-PAGE showed that the partially purified enzyme had two subunits and gel filtration chromatography showed that it consisted of four subunits of α₂β₂. The purified enzyme had a high specific activity of 860 U mg⁻¹ toward methacrylonitrile. The enzyme was found to have high activity at low temperature range, with a maximum activity occurring at 25 °C and be stable in the presence of organic acids at higher temperatures. The enzyme exhibited a preference for aliphatic saturated nitrile substrates over aliphatic unsaturated or aromatic ones. It was inhibited by sulfhydryl, oxidizing, and serine protease inhibitors, thus indicating that essential cysteine and serine residues can be found in the active site.The purified nitrile hydratase was able to convert 4-chloro-3-hydroxybutyronitrile into the corresponding amide at 15 °C. GC analysis showed that the initial conversion rate of the reaction was 215 mg substrate consumed min⁻¹ mg⁻¹. This demonstrated that this enzyme could be used in conjunction with a stereoselective amidase to synthesize ethyl (S)-4-chloro-3-hydroxybutyrate, an intermediate for a hypercholesterolemia drug, Atorvastatin.     

Thin-layer Chromatography of Some Substituted Naphthoquinones

The satisfactory method for the separation of 1,4-naphthoquinone derivatives by thin-layer chromatography, using silica gel plate and various solvents as developer, is described.

It was found that the R_F values were markedly influenced by the presence or absence of hydroxyl and amino groups.     

Residues of Aliphatic and Polycyclic Aromatic Hydrocarbons in Some Fish Species of Lake Temsah,Ismailia, Egypt: An Analytical Search for Hydrocarbon Sources and Exposure Bioindicators

Residues of aliphatic and polycyclic aromatic hydrocarbons (PAHs) were monitored in some fish species collected from Temsah Lake, near Ismailia, Egypt. Fish were selected to represent different feeding habits and ecological niches in the lake's ecosystem. Fish samples were extracted using organic solvents, and residues of aliphatic and PAHs were separated using column chromatography and detected using gas liquid chromatography. Fish species were Clupea sirm, Mugil sehli, Mugil capito, Morone labrax, and Sciasna sp. Clupea sirm, a surface feeder fish had the highest concentration of aliphatic hydrocarbons, 320 ± 54 ng g^?1, while Morone labrax, a predatory fish that live in the water column, had the highest concentration of PAHs, 315.87 ± 46 ng g^?1. Even-number aliphatic hydrocarbons were more frequently detected in all fish species in comparison to odd-number aliphatic hydrocarbons, suggesting a petrogenic origin of these compounds. Meanwhile, the pattern of PAHs detected in the present study suggested that they originate from atmospheric deposition rather than land-based runoff. Morone labrax fish and Clupea sirm fish were the most suitable candidate bioindicators of exposure to aliphatic hydrocarbons and PAHs through fish consumption of the five fish species examined in this study.     

Acetonitrile-based solvents: Their application in thin-layer chromatography of cyclic nucleotides, nucleosides, purine, and pyrimidines

Acetonitrile-based solvent mixtures have been applied to the separation of nucleotides, nucleosides, purines, pyrimidines, and cyclic nucleotides by thin-layer chromatography. The R_f's of over 35 compounds are presented. Development times with some of the systems were as low as 16 min. The use of acetonitrile-containing solvents in adenyl cyclase and cyclic phosphodiesterase assays and in the nucleotides and nucleic acid fields is discussed.     

Synthesis of Suberin during Wound-healing in Jade Leaves, Tomato Fruit, and Bean Pods

The structure and composition of the aliphatic monomers of the polymeric material deposited during wound-healing of tomato fruit, bean pods, and Jade leaves were examined. After removing the cuticle-containing layer of tissue, the wounds were healed for 14 days and the resulting surface layer was excised, lyophilized, solvent-extracted, and depolymerized by hydrogenolysis with LiAlH₄ or transesterified with BF₃ in methanol. The products obtained by the chemical depolymerization were subjected to thin layer chromatography and combined gas chromatography and mass spectrometry. The major aliphatic components isolated from the hydrogenolysate of the wound polymer produced by tomato fruit were hexadecane-1,16-diol and octadec-9-ene-1,18-diol, which were shown to be derived from a 1:1 mixture of ω-hydroxy and dicarboxylic acids of the appropriate chain length by LiAlH₄ reduction. Also identified in the wound polymer were long chain (>C₂₀) fatty acids and alcohols. This monomer composition is typical of suberin polymers and is in sharp contrast with that of the cutin of tomato fruit which contains dihydroxy C₁₆ acid as the major aliphatic component. The hydrogenolysis of the wound material from bean pods gave octadecene-1,18-diol as the major aliphatic component, and smaller amounts of hexadecane-1,16-diol and long chain alcohols. Similar treatment of the normal cuticular tissue of these pods gave hexadecane triol, as well as C₁₆ and C₁₈ alcohols. Hydrogenolysis of wound material from the Jade leaves gave octadecene-1,18-diol, C₁₆ and C₂₂ diols, as well as alcohols from C₁₆ to C₂₆, whereas similar treatment of the cutin-containing tissue from these leaves gave C₁₆ triol as the major aliphatic component. Thus, the major aliphatic monomers of the polymeric material deposited during the wound-healing of bean pods and Jade leaves are very similar to those of suberin, although the natural protective polymer of these tissues is cutin. From these results, it is concluded that suberization is a fundamental process involved in wound-healing in plants, irrespective of the chemical nature of the natural protective polymer of the tissue.     

Study on the purification of polysaccharides from Noscoc flagelliforme with radial flow chromatography

The isolation and purification of polysaccharide from Noscoc flagelliforme by radial flow chromatography were studied. The column (7.7 cm of bed length and 229.6 cm³ of bed volume) was packed with DEAE-01 anion ion-exchange resin and gradient eluted with NaCl solutions. The content of the polysaccharide was determined with the phenol-sulfuric acid method. The effects of sampling weight, elution velocity, and elution concentration gradient on the separation efficiency were examined and three isolated peaks were obtained. The optimal separation conditions are 10 mg of the sampling weight (sampling volume is 20 mL), 1.0 mL/min of the elution velocity, and 1.00 mol/L² of NaCl gradient elution. The adjacent peak resolutions among the three main components (1, 2, and 3 according to their elution order) are 0.660 (R ₁₂) and 0.786 (R ₂₃), respectively. It is deduced that 39.8 cm of the bed length is required for the fully separation of the three polysaccharides. An erratum to this article can be found at     

Catabolism of 1,2-diarylethane lignin model compounds by two brown-rot fungi

The catabolism of dimethoxybenzil, anisoin and hydroanisoin in nitrogen-limited stationary cultures of the brown-rot fungi Wolfiporia cocos and Gloeophyllum trabeum was analyzed. These three 1,2-diarylethane lignin model compounds, which differ in the degree of oxidation of the alkylic chain, gave rise to p-anisaldehyde in both cultures, suggesting that cleavage between the two aliphatic carbons had occurred. In turn, both strains reduced dimethoxybenzil and anisoin to hydroanisoin, whereas only Wolfiporia cocos was able to oxidize hydro-anisoin to anisoin. On the other hand, chemically derived hydroxyl radical, but not superoxide radical, produced p-anisaldehyde plus other unidentified compounds from anisoin and hydroanisoin. Neither radical modified dimethoxybenzil significantly.Abbreviations HGLN high glucose, low nitrogen - HGHN high glucose, high nitrogen - HPLC high performance liquid chromatography - TLC thin layer chromatography - A anisoin - HA hydroanisoin - DMB dimethoxybenzil - OH Hydroxyl radical - O _inf2 ^sup- superoxide radical     

Changes of aliphatic C–H bonds in cyanobacteria during experimental thermal maturation in the presence or absence of silica as evaluated by FTIR microspectroscopy

Aliphatic C–H bonds are one of the major organic signatures detected in Proterozoic organic microfossils, and their origin is a topic of interest. To investigate the influence of the presence of silica on the thermal alteration of aliphatic C–H bonds in prokaryotic cells during diagenesis, cyanobacteria Synechocystis sp. PCC6803 were heated at temperatures of 250–450°C. Changes in the infrared (IR) signals were monitored by micro‐Fourier transform infrared (FTIR) spectroscopy. Micro‐FTIR shows that absorbances at 2,925 cm^?1 band (aliphatic CH₂) and 2,960 cm^?1 band (aliphatic CH₃) decrease during heating, indicating loss of the C–H bonds, which was delayed by the presence of silica. A theoretical approach using solid‐state kinetics indicates that the most probable process for the aliphatic C–H decrease is three‐dimensional diffusion of alteration products under both non‐embedded and silica‐embedded conditions. The extrapolation of the experimental results obtained at 250–450°C to lower temperatures implies that the rate constant for CH₃ (k_CH3) is similar to or lower than that for CH₂ (k_CH2; i.e., CH₃ decreases at a similar rate or more slowly than CH₂). The peak height ratio of 2,960 cm^?1 band (CH₃)/2,925 cm^?1 band (CH₂; R_3/2 values) either increased or remained constant during the heating. These results reveal that the presence of silica does affect the decreasing rate of the aliphatic C–H bonds in cyanobacteria during thermal maturation, but that it does not significantly decrease the R_3/2 values. Meanwhile, studies of microfossils suggest that the R_3/2 values of Proterozoic prokaryotic fossils from the Bitter Springs Group and Gunflint Formation have decreased during fossilization, which is inconsistent with the prediction from our experimental results that R_3/2 values did not decrease after silicification. Some process other than thermal degradation, possibly preservation of specific classes of biomolecules with low R_3/2 values, might have occurred during fossilization.     

Isolation of four high-purity dammarane saponins from extract of Panax notoginseng by centrifugal partition chromatography coupled with evaporative light scattering detection in one operation

Introduction – Centrifugal partition chromatography (CPC), as a continuous liquid–liquid partition chromatography with no solid support matrix, combined with evaporative light scattering detection (ELSD) was employed for systematic separation and purification of weak‐chromophoric saponins from a highly valued and important traditional Chinese herbal medicine, Panax notoginseng. Objective – To separate and isolate high‐purity saponins from extract of Panax notoginseng using CPC‐ELSD with a simple and low toxicity solvent system. Methodology – Samples were preparaed by extracting the root material with acetone, treated with n‐butanol and then freeze‐dried. CPC‐ELSD was applied in the separation and detection of notoginsenoside and ginsenosides from extract of Panax notoginseng using a solvent system composed of ethyl acetate–n‐butanol–water (1:1:2, v/v/v). The saponins were analysed and identified by their retention time with high‐performance liquid chromatography (HPLC) coupled with ELSD, as well as electrospray ionisation tandem mass spectrometry (ESI‐MSⁿ ) in the negative and positive ion modes with the authentic standards. Results – A total of 9.6 mg of notoginsenoside R₁, 67.8 mg of ginsenoside Rg₁, 2.3 mg of Re and 286.5 mg of Rb₁ were purified from 487.2 mg of n‐butanol extract of P. notoginseng. The purities of obtained saponins in a single run were assessed to be over 98% by HPLC‐ELSD. Conclusion – CPC‐ELSD was proved to be a very fast and efficient tool for separation of high‐purity dammarane saponins. Copyright © 2011 John Wiley & Sons, Ltd.     

A Single Column Packing for The Gas-Liquid Chromatographic Separation of Various Biologically Important Compounds

The use of a single, commercially available column packing, Tabsorb_R, is described for the g. l. c. separation of a large number of different compounds. The resolution of the homologous members of the following series of compounds was achieved: (1) saturated fatty acids (C₁-C₁₈), (2) normal aliphatic saturated dlcarboxylic acids (C₂-C₁₄), (3) normal aliphatic saturated alcohols (C₁-C₂₄), (4) normal aliphatic saturated amines (C₁C₁₂), (5) the common amino acids except arginlne, histidlne and cysteine, (6) aliphatic hydrocarbons (C₁₀-C₂₀) and (7) monosaccharides. It should be noted that twenty-two monosaccharides including three hexosamines and two anhydrohexoses, could be resolved as aldltol acetates In a single run. In addition, galacturonic, glucuronic and lduronlc acids could be separated from one another as their 1, 4-lactones. The resolution achieved in these series of compounds was found to be consistent and highly reproducible. It is of further interest that certain Isomers of the higher fatty acids and hydrocarbons with one double bond could also be separated from the normal and saturated compounds, respectively. The applicability of “Tabsorb” for the g. l. c. separation, although noted above to be considerably broad, is by far not yet exhausted. These procedures which form the basis for the quantitative determinations of the various compounds studied as demonstrated by analysis of glycopeptldes for neutral hexoses and proteins for the amino acids, can readily be adapted to preparative methods. From the biochemical point of view “Tab-sorb” is an extremely versatile column packing in that it can be used for the identification of many of the common building blocks of natural products.     

Adsorption characterisation of water and ethanol on wheat starch and wheat gluten using inverse gas chromatography

Adsorption of water and ethanol on wheat starch and wheat gluten has been studied in the temperature range of 60–150 °C using inverse gas chromatography (IGC). From the chromatographic retention data it is able to calculate the separation factors for the two solutes and obtain values for thermodynamic parameters such as Gibbs free energy (ΔG_s) and the enthalpy (ΔH_s) of adsorption of water and ethanol. The results indicate that water is adsorbed more strongly than ethanol at all temperatures, and the low temperature is found to facilitate the adsorptive separation of water from ethanol. It is also shown that the starch definitely plays a crucial role for the water and ethanol separation, despite that wheat flour includes both gluten and starch. The wheat starch is seen to have potential application in biomass water–ethanol separation to obtain fuel ethanol through the preferential adsorption of water from aqueous ethanol.     

Molecular structure of the resistant biopolymer in zygospore cell walls of Chlamydomonas monoica

The unicellular green alga Chlamydomonas monoica Strehlow is known to produce zygospores with a cell wall that is resistant against microbial and chemical attack. This resistance is thought to be due to the presence of a sporopollenin-like material. However, the resistant nature of sporopollenin-like materials seriously hampers their structural analysis. With complementary techniques such as ¹³C-nuclear magnetic resonance spectroscopy, Curie-point pyrolysis-gas chromatography/mass spectroscopy and RuO₄ chemical degradation, the chemical composition of resistant biopolymer in the isolated cell walls of C. monoica zygospores was determined. This material is composed of C₂₂–C₃₀ linear alcohols and carboxylic acids, intermolecularly linked via ester and ether-linkages similar to the resistant aliphatic biopolymers encountered in the walls of the vegetative cells of the algae Tetraedron minimum, Scenedesmus communis and Pediastrum boryanum. Received: 29 April 1998 / Accepted: 2 October 1998     

Chiral separation of neonicotinoid insecticides by polysaccharide‐type stationary phases using high‐performance liquid chromatography and supercritical fluid chromatography

The enantiomeric separations of three neonicotinoid insecticides (identified as compounds 1 , 2 , and 3 ) were performed on three polysaccharide‐type chiral columns, that is, Chiralcel OD‐H, Chiralpak AD‐H, and Chiralpak IB, by high‐performance liquid chromatography (HPLC) and supercritical fluid chromatography (SFC). Effects of the modifier percentage and column temperature on chiral recognitions of chiral stationary phases were also studied. Both 1 and 2 could be resolved on all three columns selected, with the highest R_s values obtained on Chiralpak AD‐H and Chiralcel OD‐H, respectively. However, satisfactory separation of the four stereoisomers of 3 was only achieved on Chiralcel OD‐H. Considering the effects of ethanol on the values of k, α, and R_s, we concluded that hydrogen bonding, π–π, and/or dipole–dipole interactions might be all responsible for the chiral separation. In comparison to HPLC, a shorter run time was achieved for 1 and 2 by SFC. However, 3 could not be stereoselectively resolved using SFC. On the basis of the calculated thermodynamic parameters, we found that the separation processes of enantiomers of 1 and 2 were entropy controlled and enthalpy controlled, respectively. Chirality, 2011. © 2010 Wiley‐Liss, Inc.     

Rapid Chromatographic Separation of Ribosomax Ribonucleic Acids

Reversed-phase chromatography has been applied to the rapid separation of E. coli 5S rRNA and has also been adapted for use on an analytical scale for the rapid (about 30 min) separation of small quantities (0.1 Ap₂₆₀ unit) of l6s and 23S rRNAs. Compared to other techniques, this nondestructive method is faster, more sensitive, and gives better resolution.     

Preparation and Studies of Chiral Stationary Phases Containing Enantiopure Acridino‐18‐Crown‐6 Ether Selectors

The enantiomeric separation ability of the newly prepared chiral stationary phases containing acridino‐18‐crown‐6 ether selectors was studied by high‐performance liquid chromatography (HPLC). The chiral stationary phases separated the enantiomers of selected protonated primary aralkylamines efficiently. The best results were found for the separation of the mixtures of enantiomers of NO₂‐PEA. Chirality 26:651–654, 2014. © 2014 Wiley Periodicals, Inc.