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1.
The use of a single, commercially available column packing, TabsorbR, 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 dicarboxylic acids (C2-C14), (3) normal aliphatic saturated alcohols (C1-C24), (4) normal aliphatic saturated amines (C1-C12), (5) the common amino acids except arginine, histidine 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 alditol acetates in a single run. In addition, galacturonic, glucuronic and iduronic 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 glycopeptides for neutral hexoses and proteins for the amino acids, can readily be adapted to preparative methods. From the biochemical point of view "Tabsorb" 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. 相似文献
2.
The long-chain saturated and mono-unsaturated hydrocarbon content of the juice sacs of five mandarin cultivars (Mediterranean, Honey, Wilking, Kinnow, King) were examined. Normal homologues accounted for more than 47% of the saturated and more than 75% of the monoene hydrocarbons. In the saturated fraction the major hydrocarbon was n-C25 but in the monoene fraction n-C25 predominated in Kinnow and King while C29 predominated in Mediterranean, Honey and Wilking. All five cultivars could be differentiated from each other and from other citrus species by their hydrocarbon patterns. The noticeably high normal/iso ratios of saturated C23 and C25 hydrocarbons previously shown to be characteristic of mandarin species, Citrus unshiu and C. reticulata, were also found in C. nobilis and C. deliciosa. 相似文献
3.
The spark discharge synthesis of amino acids using an atmosphere of CH4 + N2 + H2O + NH3 has been investigated with variable pNH3. The amino acids produced using higher hydrocarbons (ethane, ethylene, acetylene, propane, butane, and isobutane) instead of CH4 were also investigated. There was considerable range in the absolute yields of amino acids, but the yields relative to glycine (or -amino-n-butyric acid) were more uniform. The relative yields of the C3 to C6 aliphatic -amino acids are nearly the same (with a few exceptions) with all the hydrocarbons. The glycine yields are more variable. The precursors to the C3-C6 aliphatic amino acids seem to be produced in the same process, which is separate from the synthesis of glycine precursors. It may be possible to use these relative yields as a signature for a spark discharge synthesis provided corrections can be made for subsequent decomposition events (e.g. in the Murchison meteorite). 相似文献
4.
The production of labelled aliphatic hydrocarbons in Anacystis montana and Botryococcus braunii has been studied using Na2CO3 [14C] as a carbon source. The major hydrocarbon produced by A. montana is pentadecane (ca 93%) accompanied by a pentadecene (ca 4%) and other hydrocarbons in the range C13-C17. Long chain (C21-C 33) hydrocarbons could not be detected in this organism. The variety of unsaturated hydrocarbons (C25-C31) previously reported in Botryococcus braunii is confirmed and contrasts with the synthesis of unsaturated C17 hydrocarbons only, in axenic cultures prepared from single cell isolates of this colonial alga. 相似文献
5.
M. Luciana Villaverde Juan R. Girotti Sergio J. Mijailovsky Nicols Pedrini M. Patricia Jurez 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2009,154(4):381-386
Many species of tenebrionids produce and secrete a defensive volatile blend containing mainly benzoquinones and alkenes. In this study we characterized the volatile organic compounds (VOC) of the beetle Ulomoides dermestoides (Coleoptera: Tenebrionidae). Solid phase microextraction (SPME) coupled to capillary gas chromatography–mass spectrometry (CGC–MS) analysis was used to identify methyl-1,4-benzoquinone (MBQ), ethyl-1,4-benzoquinone (EBQ), 1-tridecene (C13:1), and 1-pentadecene (C15:1), representing more than 90% of the volatile blend. We also used CGC–MS to analyze the epicuticular hydrocarbons of U. dermestoides. Saturated, unsaturated, and branched structures with chain lengths ranging from 13 to 43 carbons were detected. n-pentacosane (C25:0) and 9,11-pentacosadiene (9,11-C25:2) were the most abundant components, representing more than 40% of the cuticular hydrocarbons. 相似文献
6.
A. I. Ukolov E. D. Kessenikh A. S. Radilov N. V. Goncharov 《Journal of Evolutionary Biochemistry and Physiology》2017,53(1):25-36
The metabolic profile of plasma of white non-linear rats was investigated under normal conditions and after chronic inhalation exposure to low doses of aliphatic hydrocarbons (HC) with the number of carbon atoms from 6 to 10. The metabolic profile was determined by a combination of gas chromatography/mass spectrometry and high-performance liquid chromatography/high-resolution mass spectrometry with the subsequent use of chemometrical methods for data treatment and presentation. It was shown that continuous 90-day exposure to a mixture of C6–C10 saturated hydrocarbons at a concentration of 160 ± 20.5 mg/m3 leads to various metabolic impairments in the liver and kidneys. Exposure to hydrocarbon mixtures at doses of 31.4 ± 5.6 and 5.2 ± 1.8 mg/m3 evoked significantly smaller changes. Novel metabolic markers of the toxic effect of low concentrations of C6–C10 aliphatic hydrocarbons were revealed. The concentration ratio of pyrophosphoric and oxalic acids in rat blood plasma was found to be the most sensitive marker called a pyrophosphate index. A hypothesis was proposed about the disturbance of the redox balance as a leading pathogenetic mechanism of neuropathies and concomitant pathologies associated with chronic HC intoxication. 相似文献
7.
Determination of structure and composition of suberin from the roots of carrot, parsnip, rutabaga, turnip, red beet, and sweet potato by combined gas-liquid chromatography and mass spectrometry 总被引:7,自引:7,他引:0
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Suberin from the roots of carrots (Daucus carota), parsnip (Pastinaca sativa), rutabaga (Brassica napobrassica), turnip (Brassica rapa), red beet (Beta vulgaris), and sweet potato (Ipomoea batatas) was isolated by a combination of chemical and enzymatic techniques. Finely powdered suberin was depolymerized with 14% BF3 in methanol, and soluble monomers (20-50% of suberin) were fractionated into phenolic (<10%) and aliphatic (13-35%) fractions. The aliphatic fractions consisted mainly of ω-hydroxyacids (29-43%), dicarboxylic acids (16-27%), fatty acids (4-18%), and fatty alcohols (3-6%). Each fraction was subjected to combined gas-liquid chromatography and mass spectrometry. Among the fatty acids very long chain acids (>C20) were the dominant components in all six plants. In the alcohol fraction C18, C20, C22, and C24 saturated primary alcohols were the major components. C16 and C18 dicarboxylic acids were the major dicarboxylic acids of the suberin of all six plants and in all cases octadec-9-ene-1, 18-dioic acid was the major component except in rutabaga where hexadecane-1, 16-dioic acid was the major dicarboxylic acid. The composition of the ω-hydroxyacid fraction was quite similar to that of the dicarboxylic acids; 18-hydroxy-octadec-9-enoic acid was the major component in all plants except rutabaga, where equal quantities of 16-hydroxyhexadecanoic acid and 18-hydroxyoctadec-9-enoic acid (42% each) were found. Compounds which would be derived from 18-hydroxyoctadec-9-enoic acid and octadec-9-ene-1, 18-dioic acid by epoxidation, and epoxidation followed by hydration of the epoxide, were also detected in most of the suberin samples. The monomer composition of the six plants showed general similarities but quite clear taxonomic differences. 相似文献
8.
Particulate material recovered over an 18-month period from sediment traps deployed at a shallow-water nearshore Antarctic
site was analysed for photosynthetic pigments, aliphatic hydrocarbons and fatty acids. All components showed a distinct seasonal
variation, with high recovery rates during the summer open-water phytoplankton bloom and low rates under winter fast ice.
The amount of trapped material differed between the two summers, indicating inter-annual variability of vertical flux associated
with differences in the intensity of the summer phytoplankton bloom. Particulate material trapped in summer was dominated
by that which originated in diatoms. High recoveries of chlorophyll a, fucoxanthin, n-C21:6 hydrocarbon, 20:5(n-3) fatty acid and shorter chain (C15–C24) aliphatic hydrocarbons all pointed to a significant summer flux of ungrazed diatoms. There were, however, also signals of
zooplankton grazing activity (notably pyrophaeophorbide a), and the presence of C18:4(n-3) and C22:6(n-3) fatty acids suggested a small flux of material from flagellates and other
sources. Longer chain n-alkanes (C25–C34) indicative of nanoplankton were detected all year, but there was no significant deposition of zooplankton material in any
sample. The major recovery rate of photosynthetic pigments was in late summer (February to April), and the major grazing signal
occurred after the peak of the summer diatom bloom. Most of the diatom bloom appeared to settle out from the water column
without being grazed. The major seasonal contrast in the biochemistry of the trapped material was the dominance of the diatom
signature in summer, and in winter the predominance (but at much lower recovery rates) of material from nanoplankton.
Received: 2 March 1998 / Accepted: 12 June 1998 相似文献
9.
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. 相似文献
10.
Klaus Haas 《Phytochemistry》1982,21(3):657-659
The mosses Andreaea rupestris, Pogonatum aloides and P. urnigerum contain surface waxes in amounts of 0.05–0.12% dry wt. The waxes consisted of esters (C38-C54), primary alcohols (C20-C32), free fatty acids (C16-C30), and alkanes (C21-C31). Additionally, aldehydes (C22-C30) were major constituents in the wax of P. urnigerum. The classes and their chain length distributions in the surface waxes of these mosses are comparable to those of epicuticular waxes of higher plants. 相似文献
11.
《Phytochemistry》1987,26(12):3265-3268
Seven species of fresh mangrove leaves were found to contain saturated normal and branched chain hydrocarbons, mostly between C16 and C36 with both odd and even carbon numbers. Significant quantitative variations were found between species. Wax esters were found to contain fatty acids with chain lengths between C12 and C22. Palmitic (16:0) and stearic (18:0) acids were the major component saturated fatty acids, whereas, oleic (18:1) and linolenic (18:3) acids were the major unsaturate α-acids. Chain lengths of the alcohols of wax esters were between C14 and C36. Significant quantitative and minor qualitative differences were noted in the alcohol composition of wax esters. Hydrocarbon and wax ester compositions were characterised by the presence of low M, components in high proportions. 相似文献
12.
《Biochimica et Biophysica Acta (BBA)/Lipids and Lipid Metabolism》1982,710(3):485-492
The major hydrocarbons of Synechococcus sp., a marine blue-green alga isolated from the Gulf of Mexico, were identified as 1-nonadecene and 1,14-nonadecadiene. The content of 1-nonadecene increased with culture age from about 0.5 mg/g dry weight in young cells to about 2.3 mg/g dry weight in old cells, while the content of 1,14-nonadecadiene remained constant with culture age at about 1 mg/g dry weight. Both [1-14C]acetate and [2-14C]acetate were incorporated to equal extents into the hydrocarbons. [1-14C]Stearate was incorporated into the hydrocarbons, but [3H]arachidate was not. The fatty acids of Synechococcus sp. were typical of blue-green algae, consisting of C16:0, C16:1, C16:1, C16:0, C18:0, C18:1, C18:2 and C18:3 fatty acids were detected. The hexadecenoic acid was shown to be 9-C16:1 while the octadecenoic acid was a mixture of 93% 11-C18:1 and 7% 9-C18:1. The fatty acid content increased during the first 4 days of growth and then decreased slightly. 相似文献
13.
The composition of the epicuticular waxes from the adaxial and abaxial surfaces of peach leaves varies considerably during one season's growth. Triterpenoid acids are major components 84–95% of the waxes from the youngest leaves but the proportions of these constituents decrease as the leaves expand. The waxes from the abaxial surfaces of fully expanded leaves consist primarily of hydrocarbons (C22–C34) and triterpenoid acids, whereas the adaxial surface waxes also contain large proportions of primary alcohols (C26-C34) and esters (C42-C52). The latter include sitosteryl esters of hexacosanoic, octacosanoic and eicosanoic acids. Variations were also noted between fully expanded leaves of different ages, the abaxial surface waxes of the oldest leaves containing the highest proportions of hydrocarbons, whilst the wax from the adaxial surface of the corresponding leaves contained the largest amounts of esters, sitosterol and hydrocarbons. 相似文献
14.
Authigenic mineralization and detrital clay binding by freshwater biofilms: The Brahmani river,India
Alexander Likhoshvay Tatiana Khanaeva Alexander Gorshkov Tamara Zemskaya Mikhail Grachev 《Geomicrobiology journal》2013,30(3):209-213
This study sought to understand the origin and fate of one of the bitumen mounds found on the bottom of Lake Baikal. These mounds are located at a depth of 900 m beneath oil spots detected on the surface of Lake Baikal (53° 18′24″, 108° 23′20″). The two mounds were sampled with a manipulator from a “MIR” deep-water manned submersible. Mature mound No. 8 was subjected to chemical and microbiological studies. Mound No. 3 was subjected only to chemical studies; we failed to perform microbiological analyses of this mound for logistic reasons. Oil spots collected from the water surface, samples of mound No. 3 and No. 8, were subjected to GC/MS analysis. The water contained aliphatic hydrocarbons with chains between C8 and C23, with the most abundant chain length being C18. Mound No. 3 with the most abundant chain length being C18 actively released oil droplets into the water. It contained 770 mg/g of C13-C32 n-alkanes, with a maximum at C23 (160 mg/g). Mound No. 8 was inactive and contained 148 mg/g of aliphatic C22-C34 n-alkanes, with a maximum at C25. Mound No. 8 also consisted of 3% inorganic matter, 48% unresolved complex mixture (UCM) and less than 1% other compounds (polyaromatic hydrocarbons, isoprenoids, carotenoids, and hopanes). The core of this sample used as inoculate, yielded Rhodococci when cultivated on oil as the only source of carbon. Cultivation of the sample on agar-containing Raymond inorganic medium with crude West Siberian oil as the only source of carbon revealed colonies of these bacteria, which all appeared identical. PCR was performed with DNA isolated from 5 colonies, using primers for 16S rRNA genes. Comparison of the sequences of the 5 PCR products over a length of 714 bp revealed that they were almost identical. Phylogenetic analysis of these homologous sequences showed that they were similar to the corresponding sequences of the genus Rhodococcus. Substrate demands, the morphology of the colonies, and SEM and TEM data confirmed that the isolates obtained could indeed be Rhodococci. All of the isolates could grow in bulk cultures with inorganic medium supplemented with crude oil. Moreover, all of the isolates degraded aliphatic hydrocarbons with lengths between C11 and C29. C23-C29 hydrocarbons were degraded completely. The isolates could grow at 4–37°C. The most unexpected finding was that of the many microorganisms capable of consuming oil, only Rhodococci exhibited this ability in the inactive bitumen mound. The possible mechanisms of how crude oil is transformed into bitumen mounds and mature bitumen are discussed. 相似文献
15.
Thomas G. Waddell Mark H. Thomasson Michael W. Moore Houston W. White Dorothy Swanson-Bean Margaret E. Green Gene S. Van Horn Henry M. Fales 《Phytochemistry》1982,21(7):1631-1633
The hexane extract of Wyethia mollis contains the n-alkanes C15-C18, C20-C25, C27 and C29. Linoleic acid was the only detectable acidic component. A mass spectral analysis of the wax ester fraction indicated that it was a mixture of homologues, the saturated even-carbon acids n-C16-C30 esterfield with the saturated even-carbon alcohols n-C18-C26. The chloroform extract yielded the known isoflavones santal and 3′-O-methylorobol along with a new lanostane-type triterpene, 22,25-epoxy-lanosta-7:9(11)-dien-3-one. The wide distribution of n-alkanes and the decreased odd-even carbon ratio are consistent with the proposed primitive nature of this plant. 相似文献
16.
J. Oro 《Journal of biological physics》1995,20(1-4):135-147
Keeping in mind the importance of amphiphilic lipids for the formation of semipermeable membranes, a review summary of the sources of appropriate precursors, and chemical reactions for the abiotic synthesis of lipids is presented here within the framework of the theory of chemical evolution. It covers the presence in different cosmic environments of precursors for the formation of the biochemical molecules necessary for the emergence of life on Earth. It starts (1) with a short introduction. Then the following matters are briefly reviewed: (2) The circumstellar and interstellar molecules, some of which, could generate straight chain fatty acids through C9. (3) The possible reactions of hydrogenation and hydrolysis of cyanopolyynes which in the presence first of hydrogen and then liquid water could lead to the formation of aliphatic acids. (4) The composition of comets, where the preliminary analysis by mass spectrometry indicate straight chain hydrocarbons through only C5. (5) The organic compounds in carbonaceous chondrites where aliphatic acids through C12 have been identified, although the branched chain isomers are abundant. (6) The synthesis of some biochemical compounds, such as amino acids present in carbonaceous chondrites, which were probably formed by condensation of presolar precursors, aldehydes and ketones, with HCN in the presence of ammonia and liquid water in the meteorite parent body. The isotopic evidence seems to support this interpretation. (7) The formation of the Earth-Moon system by the catastrophic impact of a Mars-size body with the proto-Earth. (8) The subsequent capture of cometary water, organic and inorganic compounds, which must have led to a very reactive primitive Earth's atmospheric environment. The cometary iron-nickel grains could have catalyzed the formation of fatty acids by Fischer-Tropsch reactions. (9) The laboratory synthesis of straight chain fatty acids from C5 through C20 by Fischer-Tropsch processes. The amounts are usually in excess of the yields of aliphatic hydrocarbons. The chemical synthesis of glycerophospholipids including phosphatidylcholine. (10) The formation of liposomes, primarily, from phosphatidylcholine and the encapsulation within them of biopolymers. (11) Speculations on protocellular models of increasing complexity based on liposomes enclosing catalytic biomolecules. (12) Finally, some of the important problems remaining to be solved concerning the experimental approach to the study of the origin of life are briefly considered. It is hoped that in the next century, significant advances will be made in our understanding of the origin of life on Earth. 相似文献
17.
The monocarboxylic fatty acids and hydroxy fatty acids of three species of freshwater microalgae—Vischeria punctata Vischer, Vischeria helvetica (Vischer et Pascher) Taylor, and Eustigmatos vischeri (Hulbert) Taylor, all from the class Eustigmatophyceae— were examined. Each species displayed a very similar distribution of fatty acids, the most abundant of which were 20:5n-3, 16:0, and 16:1n-7; C18 polyunsaturated fatty acids were minor components. These fatty acid distributions closely resemble those found in marine eustigmatophytes but are quite distinct from those found in most other algal classes. These microalgae also contain long-chain saturated and unsaturated monohydroxy fatty acids. Two distinct types of hydroxy fatty acids were found: a series of saturated α-hydroxy acids ranging from C24 to C30 with a shorter series of monounsaturated α-hydroxy acids ranging from C26 to C30 together with a series of saturated β-hydroxy acids ranging from C26 to C30. The latter have not previously been reported in either marine or freshwater microalgae, although C30 to C34 midchain (ω-18)-hydroxy fatty acids have been identified in hydrolyzed extracts from marine eustigmatophytes of the genus Nannochloropsis, and C22 to C26 saturated and monounsaturated α-hydroxy fatty acids have been found in three marine chlorophytes. These findings have provided a more complete picture of the lipid distributions within this little studied group of microalgae as well as a range of unusual compounds that might prove useful chemotaxonomic markers. The functions of the hydroxy fatty acids are not known, but a link to the formation of the lipid precursors of highly aliphatic biopolymers is suggested. 相似文献
18.
Yu Suen Gunther U. Holzer Jerry S. Hubbard Thomas G. Tornabene 《Journal of industrial microbiology & biotechnology》1988,2(6):337-348
Summary The hydrocarbon composition ofPseudomonas maltophilia was determined by gas chromatography-mass spectrometry. Mono-, di- and tri-unsaturated alkenes were identified with a predominance of polyunsaturated components. The carbon chains of the alkenes contained single methyl branches iniso andanteiso position and double methyl branches in theiso-iso andanteiso-anteiso configurations. The composition of the hydrocarbons from cells grown in synthetic media enriched with amino acids or volatile fatty acids demonstrated that the probable precursors incorporated into individual hydrocarbons were branched and normal fatty acid chains in the range from C3 to C16. The probable fatty acid precursors which were connected together to form the major triunsaturated hydrocarbon chains were two monounsaturated chains, whereas the major liunsaturated chains resulted from condensation of saturated and monounsaturated chains. The probable precursors for the major monounsaturated hydrocarbons were C14 (C15) and C16 (C15) fatty acids. The accumulation of hydrocarbons was not detected until the cells were in the late exponential phase of growth; the maximal levels were reached at the mid-stationary phase of growth. 相似文献
19.
Biosurfactants from Bacillus licheniformis: structural analysis and characterization 总被引:6,自引:0,他引:6
Katharina Jenny Othmar Käppeli Armin Fiechter 《Applied microbiology and biotechnology》1991,36(1):5-13
Summary The surface-active compounds of the strain Bacillus licheniformis were isolated and their structure was elucidated. The high surface-active capacity of the crude extract was basically due to traces of long-chain saturated fatty acids, especially of palmitic and stearic acids, to a mixture of small amounts of hydrocarbons with chain lengths of 20 and 22 carbons, and mainly to appreciable amounts of four slightly different lipopeptides. The lipopeptides were found to be a mixture of four closely related compounds. The lipophilic part consisting of i-, n-C14 or i-, ai-C15 -OH fatty acids was linked to the hydrophilic peptide moiety, which contained seven amino acids (Glu, Asp, Val, three Leu and Ile) by a lactone linkage. Fifteen milligrams per litre of the purified lipopeptide product decreased the surface tension of water from 72 mN m–1 to 27 mN m–1, characterizing the product as a powerful surface-active agent that compares favourably to other (bio)surfactants. Antibiotic activity was demonstrated against bacteria and yeasts.
Offsprint requests to: O. Käppeli 相似文献
20.
The lipid fraction of the green alga Botryococcuscultured in a batch mode was found to contain polar lipids (more than 50% of the total lipids), di- and triacylglycerols, sterols and their esters, free fatty acids, and hydrocarbons. In aging culture, the content of polar lipids somewhat decreased and that of triacylglycerols increased by more than four times. The content of hydrocarbons in the algal biomass did not exceed 0.9% and depended little on the culture age. Intracellular lipids contained saturated and unsaturated (mono-, di-, and trienoic) fatty acids. The maximum content of C16 : 3and -C18 : 3fatty acids (up to 35% of the total fatty acids) was detected in the phase of active growth. The extracellular and intracellular lipids of the alga differed in the proportion of particular lipids and in the fatty acid pattern. 相似文献