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1.
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   

2.
Three varieties of midseason oranges, viz. Jaffa, Homosassa and Queen, were examined for their saturated and mono-unsaturated hydrocarbon composition in juice sacs. Hydrocarbons were isolated by lipid extraction of the juice sac powders followed by column, thin-layer and AgNO3-TLC. After hydrogenation, the mono-unsaturated fraction and the saturated fraction were analyzed by GC. In the saturated fraction, the dominant linear hydrocarbon was C23 while C25 predominated in the monoene fraction. iso- And anteiso-branched hydrocarbons comprised between 53 and 63 % of the saturated fraction and only 20–26 % of the monoene fraction. Queen differed from Homosassa and Jaffa in the accumulation of higher percentages of saturated iso- and anteiso-branched hydrocarbons and conversely, showed lower percentages for these branched structures in the monoene fraction. Based on the total relative percentages of the three isomeric hydrocarbons, Homosassa could not be differentiated from Jaffa. The overall profiles for these two oranges, however. showed noticeable differences.  相似文献   

3.
Three varieties of lemon—Lisbon, Malta and Kusner—were examined for their content of juice sac saturated and mono-unsaturated long-chain hydrocarbons. The saturated fractions were 20 times the concentrations of the monoene fractions. The dominant linear hydrocarbon in the saturated fraction was C25 while C29 predominated in the monoene fraction. The saturated hydrocarbon profiles for Lisbon and Kusner were very similar to the profiles previously reported for Eureka lemon and Persian lime. The mono-unsaturated profiles were distinct for each of the three lemon varieties. In addition the lemon mono-unsaturated profiles were quite distinct from the hydrocarbon profiles previously reported for several other citrus species. In general the data support the elongation-decarboxylation mechanism for hydrocarbon synthesis proposed by Kolattukudy.  相似文献   

4.
Dietary hydrocarbons are incorporated into cuticular lipids of the grasshopper Melanoplus sanguinipes. Dietary secondary alcohols and ketones, however, are not incorporated into the cuticular lipids. In typical experiments from 8 to 28 per cent of the fed labeled n-alkanes are recovered in the cuticular lipids. Most of the radioactivity recovered from feeding the C23 n-alkane and a significant amount from the C25 was found as a secondary alcohol in the form of a wax ester. The C29 and C31 n-alkanes were recovered primarily unchanged as the n-alkane. Eighty-five per cent of injected acetate incorporated into the hydrocarbon fraction is in the branched hydrocarbons. These results show that the insect synthesizes its branched hydrocarbons, whereas a large part of the normal hydrocarbons can be dietary.  相似文献   

5.
The composition of the unsaponifiable matter of the lipids of six Adansonia species (A. grandidieri, A. za, A. fony, A. madagascariensis, A. digitata and A. suarezensis) was investigated. The total unsaponifiable content, its general composition and the identity of the components of the hydrocarbon, sterol and tocopherol fractions are presented. The unsaponifiable content in oil ranges from 0.4 to 1.1% (hexane method) and from 0.6 to 2.2% (diethyl ether method). In two species (A. grandidieri and A. suarezensis) the major components are 4-demethylsterols (23–42%) tocopherols (37-10%) and hydrocarbons (15–17%). In both species examined, eight 4-demethylsterols occur in the sterol fraction with sitosterol (81–88%) being predominant. Among the four tocopherols present, γ-tocopherol (68–98%) is the major compound. Each Adansonia species shows a characteristic gas liquid chromatography pattern for the hydrocarbon fraction. Squalene is the major component for five species (40–75%). Iso-, anteiso- and other branched hydrocarbons were not identified but were present in small amounts in comparison with n-alkanes. The dominance of odd- over even-carbon number chain length of n-alkanes was not observed in any species. The results show that C22, C25, C26, C27, C28 and C29 are the most frequent major constituents.  相似文献   

6.
  • 1.1. The Dufour gland secretions of Formica fusca consist mainly of saturated straight and branched chain hydrocarbons (C9–C19), one unsaturated hydrocarbon (C13) and two sesquiterpenoids, farnesene and homofarnesene.
  • 2.2. In F. lemani, the Dufour gland contains branched, saturated and unsaturated hydrocarbons (C9–C19) and two farnesenes.
  • 3.3. The two species were distinguished chiefly by the presence of a relatively large proportion of farnesene in F. fusca, with very little homofarnesene and by contrast, little farnesene but much more homofarnesene in F. lemani.
  • 4.4. The contents of the Dufour gland can be used as a chemotaxonomic clue to distinguish between the species.
  相似文献   

7.
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   

8.
Material from the testa of decorticated barley grains contained hydrocarbons, esters, triglycerides, free sterols, 5-n-alkylresorcinols, and traces of free alcohols, carbonyl compounds, and various polar, acidic materials. The hydrocarbon fraction was mainly a series of n-alkanes, extending at least from C11 to C36, in which the C29 and C31 components were prominent. Two minor series of alkanes were also present. Sometimes a trace of an unsaturated hydrocarbon was detected. The ester fraction contained sterols and alkanols esterified by fatty acids, which differed in relative amounts from the fatty acids found in the triglycerides. The triglycerides were thought to have leached from within the grain. At least five free sterols were present, including sitosterol and campesterol. The 5-n-alkylresorcinols were at least twelve members of a homologous series, of which four, C25, C27, C29, and C31, made 98% of the total. Members of the series with even numbers of carbon atoms were also present. It is suggested that they are partly responsible for excluding microorganisms from the interior of the grain. The testa membrane, with the associated pigment strand, contained an estolide of fatty acids and various hydroxyacids, a polysaccharide component, and uncharacterized material.  相似文献   

9.
The carbon source markedly influenced the qualitative and quantitative composition of cellular hydrocarbons in Cladosporium resinae. Total lipid and hydrocarbon content was greater in cells grown on n-alkanes than in cells grown on glucose or glutamic acid. Glucose-grown cells contained a spectrum of aliphatic hydrocarbons from C7 to C36; pristane and n-hexadecane comprised 98% of the total. Cells grown on glutamic acid contained C7 to C23 hydrocarbons; n-tridecane, n-tetradecane, n-hexadecane, and pristane made up 74% of the total. n-Decane-grown cells yielded C8 to C32 compounds, and n-hexadecane (96%) was the major hydrocarbon. Cells grown on individual n-alkanes from C11 to C15 all contained C11 to C28 hydrocarbons, and cells grown on n-hexadecane contained C11 to C32 hydrocarbons. In n-undecane-grown cells, n-hexadecane and pristane made up 92% of the total, but in cells grown on C12 to C16 n-alkanes the major cellular hydrocarbon was the one on which the cells were grown. This suggests that cells cultured on n-alkanes of C12 or longer accumulate n-alkanes prior to oxidizing them.  相似文献   

10.
IR assay for sapogenin of Balanites wilsoniana revealed 0.2% in the root wood, 0.7% in the root bark, 0.3% in the stem bark, 1.4% in the fatty seed and 0.6%. w/w in the leaf. The 25 α-epimers predominated in all parts except in the root wood. Six glucosideshaving diosgenin or yamogenin as aglycones were found and one was characterized diosgenin 3 β-d-glucopyranoside from IR, MS and NMR studies. Cholesterol, stigmasterol, sitosterol, 25 α-spirosta-3:5-diene and 25-β-spirosta-3:5-diene were also present. Free diosgenin and dienes were detected in appreciable quantities in the fat from the bark. The ‘unsaponifiable’ fraction of this fat contained phthalyl esters (mainly dioctyl and dibutyl) and saturated hydrocarbons C10C32 (with C10C20 predominating), together with the above mentioned steroids.  相似文献   

11.
《Insect Biochemistry》1985,15(1):25-34
Epicuticular hydrocarbons of Drosophila pseudoobscura were analyzed by gas chromatography and mass spectrometry. Methyl-branched alkanes and alkadienes were the predominant hydrocarbons, with lesser amounts of monoenes (14%) and trienes (9%) also present. Alkanes (49%) were mostly odd carbon number 2-methylalkanes (C25–C31). Alkadienes (27%) were odd carbon number components (C25–C33), with the (Z,Z)-5,9-isomer predominating. Monounsaturated hydrocarbons were a mixture of 5-, 7-, 9-, 11-, 13-, 14- and 15-isomers containing 25–33 carbon atoms. The major alkatriene components contained 29–31 carbon atoms and were either 5,19,17- or 5,9,19-isomers. Sodium[1-14C]acetate was incorporated into each class of hydrocarbon and into each of the major alkadienes.  相似文献   

12.
Abstract: Hydrocarbons associated with the developing microspores in the anther loculus of Tulipa cv. Apeldoorn were investigated. They occurred mainly at chain lengths between C19 and C29. At the lower chain lengths the n-alkanes, at higher chain lengths the alkenes dominated. During microspore development the ratio of unsaturated to saturated hydrocarbons in the extracts changed. While the content of all main hydrocarbons increased, the content of the alkanes C19, C21 and C23 increased to 3.8, 3.4 and 3.3 times the initial value compared to 2.1, 2.0 and 2.2 times in case of the alkenes C25, C27 and C29. Surface lipids from petals, leaves and ripe pollen were analyzed in comparison and these analyses confirmed that a high amount of alkenes was unique for microspores. Iso-heptacosane was the main hydrocarbon from ripe pollen, heptacosene was a main component when microspore extracts were analyzed.  相似文献   

13.
The analysis of fatty acids and hydrocarbons in the sporophytes of three Lycopodium species has revealed a characteristic distribution of C16 and C18 acids. The hydrocarbon fraction of the lipids contain a homologous series of monounsaturated alkenes in the C17C30 range with an even to odd preference. Maxima at both C17 and C27 among the n-alkanes reveals similarities both to the distribution of hydrocarbons in other plant groups. The production of spores and their inclusion with one sporophyte does not alter the fatty acid pattern but does decrease the alkene concentration and modifies the alkane distribution, shifting both maxima. The presence of pristane and phytane in all specimens, the dual maxima of alkanes and slight odd to even preference of alkanes is noteworthy in that these characteristics are possessed by geological deposits derived from Lycopodium ancestors.  相似文献   

14.
Samples of the green colonial alga Botryococcus braunii, collected from various localities, were grown in the laboratory and examined for their hydrocarbon content and morphology. Although few differences appeared between the ultrastructures of the samples, the nature of their hydrocarbons, which remains unchanged at any stage of growth, allows the distinction of two physiological races viz algae producing odd-numbered unbranched alkadienes and trienes (C25C31) (the A race) and those producing polymethylated triterpenes CnH2n-10 (C30C37), the botryococcenes (the B race). In laboratory culture, the hydrocarbon content of these new strains is very high, from 30 to 60% of the dry biomass. For the two races the greatest hydrocarbon productivity takes place during the active growth phase. The important variability observed in botryococcene distribution could originate both from genetic and environmental factors.  相似文献   

15.
Two nanoplanktonic marine coccolithophores, Emiliania huxleyi and Gephyrocapsa oceanica, were grown at 23°C with a 16-hour light and 8-hour darkness regimen. The cells were dried at room temperature and then subjected to pyrolysis at 100° to 500°C under anoxygenic conditions to produce hydrocarbons. Temperature-dependent profiles of the liquid-saturated hydrocarbons (saturates) produced during pyrolysis were very similar for the two strains, although the total amount was higher in E. huxleyi than in G. oceanica. The amount of saturates produced was only 0.05% to 0.15% below 200°C, but about 2.1% to 2.8% at 300°C. Their major components were normal alkanes in a series ranging from nC11 to nC35 with the predominant peak at nC15. At 400° and 500°C most of saturates transformed into gaseous compounds. The major saturates identified in all pyrolysates were normal C31 monounsaturated and diunsaturated alkenes, a series of normal alkanes, phytenes, C28 sterenes, and steranes. Profiles of saturates in gas chromatography–mass spectroscopy varied with increasing pyrolysis temperature and also differed between E. huxleyi and G. oceanica. The two coccolithophores are useful candidates for the production of renewable liquid fuel through pyrolysis—especially E. huxleyi, which has higher production. The results also provide information for further studies on the characterization, source, and paleogeographic distribution of marine sediment. Received October 28, 1998; accepted February 15, 1999  相似文献   

16.
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   

17.
Soil vapor data for benzene and four aliphatic and aromatic hydrocarbon fractions from five volatile petroleum hydrocarbon (VPH)-contaminated sites in western Canada were used together with the Canadian Council of Ministers of the Environment (CCME) Canada-Wide Standard for petroleum hydrocarbons to investigate the relative importance of benzene and the different fractions in human health risk assessment. VPH concentrations in soil vapor samples ranged from 4.0 to 4200?mg/m3, of which 0 to 4.6% was BTEX and 90 to 95% was hydrocarbons of the C5–8 aliphatic fraction. VPH inhalation exposure by an adult receptor in a hypothetical, commercial building was modelled deterministically assuming 16- and 70 year occupational tenures. The magnitude of hazard quotients varied widely between sites, but their hydrocarbon fraction signatures were consistent, and characterized by higher hazard quotients in the C5–8 and C9–10 aliphatic and C9–10 aromatic fractions relative to benzene and the TEX aromatic fraction. This work has shown that the C5– and C9–10 aliphatic fractions yield greater relative risk than the commonlyregulated TEX compounds, and that benzene becomes the primary chemical of potential concern only when an occupational tenure approaching 70 years is assumed.  相似文献   

18.
Proteinase production by Pseudomonas aeruginosa was studied in medium containing noncarbohydrate materials, especially various hydrocarbons, as the sole carbon source. On heavy oil, kerosene, n-paraffinic hydrocarbon of C12, C14, or C16, and propylene glycol, the bacteria grew well and high protinase production was observed. However, production on paraffinic hydrocarbon differed remarkably with strains of varied origins. The elastase-positive strain, IFO 3455, showed abundant growth and high proteinase production on medium containing a paraffin of C12, C14, or C16, whereas the elastase-negative strain, IFO 3080, showed little growth on the same medium. Neither elastase-positive nor elastase-negative strains, however, utilized n-paraffins of C5 to C10, or various aromatic hydrocarbons such as benzene, naphthalene, phenanthrene, and anthracene. The proteinases produced on the noncarbohydrate medium were identical with those produced in glucose medium.  相似文献   

19.
The role of clay minerals in crude oil saturated hydrocarbon removal during biodegradation was investigated in aqueous clay/saturated hydrocarbon microcosm experiments with a hydrocarbon degrading microorganism community. The clay minerals used for this study were montmorillonite, palygorskite, saponite and kaolinite. The clay mineral samples were treated with hydrochloric acid and didecyldimethylammonium bromide to produce acid activated- and organoclays respectively which were used in this study. The production of organoclay was restricted to only montmorillonite and saponite because of their relative high CEC. The study indicated that acid activated clays, organoclays and unmodified kaolinite, were inhibitory to biodegradation of the hydrocarbon saturates. Unmodified saponite was neutral to biodegradation of the hydrocarbon saturates. However, unmodified palygorskite and montmorillonite were stimulatory to biodegradation of the hydrocarbon saturated fraction and appears to do so as a result of the clays’ ability to provide high surface area for the accumulation of microbes and nutrients such that the nutrients were within the ‘vicinity’ of the microbes. Adsorption of the saturated hydrocarbons was not significant during biodegradation.  相似文献   

20.
A strain Botryococcus braunii Kütz. that produces high levels of branched hydrocarbons (botryococcenes) was grown under different environmental conditions to investigate the relationship between growth and hydrocarbon production. Carbon dioxide concentration had the most significant influence on growth; 0.3% CO2-enriched cultures demonstrated a minimum mass doubling time of ca. 40 h, compared to ca. 6 days for ambient air cultures grown on the same buffered growth medium. The botryococcene fraction, which consisted of 10 identified compounds (CnH2n-10; n = 30–34), usually constituted ca. 25–40% of the culture dry weight under various growth regimes, including nitrogen- and/or phosphate-deficiencies. CO2 enrichment initially favored the production of the lower botryococcenes (C30–C32), whereas relatively slow-growing ambient air cultures accumulated C33 and C34 compounds. Colony color changed in response to different light intensities. High light increased the carotenoid/chlorophyll ratio, which resulted in orange colonies. Cultures exposed to low light intensity appeared green. This change in coloration was reversible over a period of a few days, and at no time were the linear hydrocarbons characteristic of the other form of the alga detected. Ostensible colony color is not, therefore, a reliable indicator of qualitative hydrocarbon content. Sequential solvent extraction experiments indicated that up to ca. 7% of the botryococcene fraction was intracellular and that the remainder was located within the colonial matrix. The internal (cellular) pool principally consisted of C30–C32 botryococcenes, whereas the external (colonial matrix) pool contained >99% of the C33 and C34 compounds, in addition to large amounts of the lower botryococcenes. These results, taken in conjunction with other data, are compatible with the hypothesis that the C30 botryococcene is the precursor, presumably via methylation, of the higher botryococcenes.  相似文献   

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