首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
D.R. Body 《Phytochemistry》1974,13(8):1527-1530
The neutral lipids of white clover leaves and stems have been separated into wax esters, free fatty acids, free fatty alcohols, free sterols, triglycerides and hydrocarbons. The wax esters were mainly of C18 di- and tri-unsaturated fatty acids and C30 fatty alcohol. Linolenic acid was the predominant free fatty acid and triacontanol was the principal free fatty alcohol. Of the hydrocarbons, C29 and C31 were present in the largest amounts.  相似文献   

2.
The epicuticular waxes of the two sorghum varieties Alliance A and SD 102 have been analyzed, after separation of the leaf blades from the sheaths. The major constituents were found to be free fatty acids but small amounts of esters, aldehydes, alcohols, n-alkanes and sterols were also detected. The typical chain lengths of aldehydes, free alcohols and free fatty acids were C28 and C30.  相似文献   

3.
When n-alkanes with 13 to 20 carbon atoms were fed to a Nocardia closely related to N. salmonicolor, the produced cellular triglycerides and aliphatic waxes invariably contained fatty acids with an even or an odd number of carbon atoms subject to this feature of the n-alkane substrate. Beta-oxidation and C2 addition are both operative, as evidenced by the spectra of fatty acids incorporated into the cellular lipid components. There is no distinction in the rate of microbial incorporation of the odd-or even-numbered carbon chains. The fatty acids are apparently directly derived from the long chain n-alkanes, rather than synthesized via the classic C2-condensation route. The alcohol component of waxes produced by the Nocardia is invariably of the same chain length as the n-alkane substrate.  相似文献   

4.
Cells derived from Antheraea eucalypti were grown in vitro in a medium containing triglycerides, diglycerides, free fatty acids, and sterols as the main ‘neutral’ lipids. The sterol content of the medium was derived chiefly from the haemolymph component. The ‘neutral’ lipids in the cells were triglycerides, free fatty acids, and sterols. During growth over 6 days there was a quantitative balance between cholesterol and β-sitosterol gained by the cells and those sterols removed from the medium when allowance was made for losses from sterile medium. Cells metabolized more triglycerides and free fatty acids than they incorporated.  相似文献   

5.
The composition of the sterols, sterol esters and fatty acids has been determined in 8-, 11- and 14-day cultures of three members of the Xanthophyceae, Botrydium granulatum, Tribonema aequale and Monodus subterraneus. The main sterols, whether esterified or unesterified, were cholesterol and clionasterol, whose proportions do not vary with age of culture. Much smaller quantities of cycloartenol and 24-methylenecycloartanol were also found in all three algae. The C16 fatty acids are the most common fatty acids in all three algae with C16:1 being particularly abundant. B. granulatum and T. aequale, however, differ from M. subterraneus in having polyunsaturated C16 fatty acids and a smaller proportion of C20:5.  相似文献   

6.
Seed triglycerides of Andropogon gayanus contained 17 fatty acid moieties, principally palmitic, oleic and linoleic acids. These were distributed in an essentially random manner amongst the triglycerides to form the following main types: POL, PLL, OOL, LLO and LLL. Triglycerides decreased during both light and dark germination but there was no evidence for selective hydrolysis. Free fatty acids appear to be derived from triglyceride hydrolysis but the free and triglyceride fatty acid composition differed. Less palmitic, oleic and linoleic acids and more stearic, linolenic and C20-acids were found in the free state than combined in the triglycerides. Free fatty acids did not accumulate during germination.  相似文献   

7.
A detailed chemical analysis of the benzene extract of western white pine bark was conducted. The extract consisted of 13% phlobaphenes, 18% strong acids, 21% polar weak acids, 6.5% fatty acids, 9.5% resin acids, and 32% neutrals. The fatty acids consisted mainly of C20:0, C22:0, and C24:0 acids. The resin acids were identified as: isopimaric, anticopalic, dehydroabietic, sandaracopimaric, abietic, 6,8,11,13-abietatetraen-18-oic and pimaric acids. The neutrals on saponification gave fatty acids, sterols, wax alcohols, nonsaponifiables, and other components. The esterified fatty acids consisted primarily of the C16:0, C18:0, C20:0 and C24:0 acids. The sterols included major amounts of sitosterol, campesterol, and stigmasterol, and traces of cholesterol. Over 70 individual compounds were isolated and identified from the nonsaponifiables. These included borneol, sesquiterpenes, diterpenes, steroidal ketones, as well as lanostane and serratane triterpenes. The characterization of12 new natural products or natural products isolated for the first time from Pinus species is reported.  相似文献   

8.
Dried fruiting bodies of the basidiomyceteOudemansiella mucida contain 29.1% total lipids. Their qualitative analysis revealed the presence of mono-, di-, triglycerides, sterols, free fatty acids and sterolesters. Quantitatively most significant were triglycerides (37.9%) and free fatty acids (29.7%). The phospholipid fraction contained phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine and phosphatidic acid. Gas chromatography showed the presence of a broad spectrum of fatty acids. The ratio between the neutral and polar fractions was 6: 1, both having linoleic acid as the main component.  相似文献   

9.
Constituents of the venom (1) and Dufour's gland (25) have been characterized in an Australian representative of the highly evolved ant subfamily Formicinae. The venom reservoir of this ant, Camponotus intrepidus, contains formic acid, identified as the benzyl ester. The Dufour's gland contains a major hydrocarbon and a minor fatty acid fraction. Hydrocarbons include the normal alkanes, C10 to C17 (82 per cent); two series of monomethylalkanes, C12, C13, C14, C16, and C17, the 3-methyl derivatives comprise approximately 16 per cent, and the 5-methylalkanes 2 per cent of the total; there are trace proportions of the n-alkenes, C12, C13, and C15. The minor fatty acids, myristic, pentadecanoic, palmitic, and stearic are present in the ratio 2 : 2 : 12 : 11.  相似文献   

10.
《Plant science》1987,53(1):35-38
Experiments were conducted employing saturated C4, C6, C8, C9, C10, C12 and C18 fatty acids, their methyl esters, C8 fatty alcohol, C8, C10 and C12 mono-, di- and triglycerides and C18 mono- and triglycerides on the inhibitory activity against growth of the Avena coleoptiles. The C8, C9 and C10 fatty acids, and the methyl ester of C10 had strong activity which gradually reduced with either increased or decreased carbon chain length. The C10 monoglyceride also exhibited strong activity whereas no effect was found in other glycerides.The C8 fatty alcohol was more active than the C8 methyl ester. The acyl location of the C10 monoglyceride had no effect on the high activity. Concentration of the C10 monoglyceride corresponding to 50% inhibition of the control was 2.3 × 10−4M.  相似文献   

11.
The molecular and isotopic compositions of lipid biomarkers of cultured Aquificales genera have been used to study the community and trophic structure of the hyperthermophilic pink streamers and vent biofilm from Octopus Spring. Thermocrinis ruber, Thermocrinis sp. strain HI 11/12, Hydrogenobacter thermophilus TK-6, Aquifex pyrophilus, and Aquifex aeolicus all contained glycerol-ether phospholipids as well as acyl glycerides. The n-C20:1 and cy-C21 fatty acids dominated all of the Aquificales, while the alkyl glycerol ethers were mainly C18:0. These Aquificales biomarkers were major constituents of the lipid extracts of two Octopus Spring samples, a biofilm associated with the siliceous vent walls, and the well-known pink streamer community (PSC). Both the biofilm and the PSC contained mono- and dialkyl glycerol ethers in which C18 and C20 alkyl groups were prevalent. Phospholipid fatty acids included both the Aquificales n-C20:1 and cy-C21, plus a series of iso-branched fatty acids (i-C15:0 to i-C21:0), indicating an additional bacterial component. Biomass and lipids from the PSC were depleted in 13C relative to source water CO2 by 10.9 and 17.2‰, respectively. The C20–21 fatty acids of the PSC were less depleted than the iso-branched fatty acids, 18.4 and 22.6‰, respectively. The biomass of T. ruber grown on CO2 was depleted in 13C by only 3.3‰ relative to C source. In contrast, biomass was depleted by 19.7‰ when formate was the C source. Independent of carbon source, T. ruber lipids were heavier than biomass (+1.3‰). The depletion in the C20–21 fatty acids from the PSC indicates that Thermocrinis biomass must be similarly depleted and too light to be explained by growth on CO2. Accordingly, Thermocrinis in the PSC is likely to have utilized formate, presumably generated in the spring source region.  相似文献   

12.
Lipid composition and hydrocarbon structure of two colonial green algae of the genus Botryococcus, i.e., a museum strain and a field sample collected for the first time from Lake Shira (Khakasia, Siberia), have been compared. Polar lipids, diacylglycerols, alcohols, triacylglycerols, sterols, sterol esters, free fatty acids and hydrocarbons have been identified among lipids in the laboratory culture. The dominant fraction in the museum strain was formed by polar lipids (up to 50% of the lipids) made up of fatty acids from C12 to C24. Palmitic, oleic, C16 - C18 dienoic and trienoic acids were the main fatty acids of the museum strain. Aliphatic hydrocarbons were found in the lipid of the museum strain. However, these amounted maximally to about 1% of the dry biomass at the end of exponential growth phase. The qualitative and quantitative compositions of FAs and hydrocarbons of the museum strain of Botryococcus, (registered at the Cambridge collection as Botryococcus braunii Kutz No LB 807/1 Droop 1950 H-252) differed from those of the Botryococcus strain described in the literature as Botryococcus braunii. The Botryococcus sp. found in Lake Shira is characterized by a higher lipid content (<40% of the dry weight). Polar lipids, sterols, triacylglycerols, free fatty acids and hydrocarbons have been identified among lipids in the field sample. The main lipids in this sample were dienes and trienes (hydrocarbons <60% of total lipid). Monounsaturated and very long chain monounsaturated fatty acids, including C28:1 and C32:1 acids, were identified in the Botryococcus found in Lake Shira. The chemo-taxonomic criteria allow us to unequivocally characterize the organism collected from Lake Shira as Botryococcus braunii, race A.  相似文献   

13.
  1. Endomycopsis vernalis was cultivated on media with different N supply: series A 1%, series B 0,125% asparagine. Sonified cells were extracted and yielded 14.3% (A) and 65.3 (B) total lipids/non lipid dry matter respectively.
  2. Neutral and complex lipids were separated by rubber membrane dialysis. There is no difference in the percentage of complex lipids of both series. The increase of lipids in cells grown on low N level is due to a higher content of neutral lipids.
  3. Components of the neutral lipids, analysed by DC, were diglycerides, triglycerides, free and esterified ergosterol. Their percentage is influenced by the nutritional conditions. There is a significant increase of triglycerides and of sterol esters in the high lipid cells of series B.
  4. Methyl esters of component fatty acids of glycerides and sterol esters were analyzed by GLC. Saturated acids C14, C15, C16, C17, C18, monoenic acids C16 and C18, linoleic and linolenic acids were found to be present. Major acids were in all cases 18:1 (17–57%), 18:2 (18–50%) and 16:0 (10–18%). Linolenic acid is higher in di-and triglycerides of low lipid cells of series A than in high lipid cells of series B. Both qualitative and quantitative differences of fatty acids were found in sterol esters of series A and B respectively.
  5. The major components of complex lipids, identified by DC and isolated by CC, in both series, were phosphatidyl choline (A:36.5, B:41.0%) and phosphatidyl ethanolamine (A:24.9, B:20.5%) in addition to small amounts of lysophosphatidyl choline, lysophosphatidyl ethanolamine, phosphatidyl serine, monophosphoinositide, diphosphatidyl glycerol and, possibly cerebroside like substances.
  6. Methyl esters of the fatty acids of phosphatidyl choline and ethanolamine from both series were determined by GLC. In all samples 16:0, 18:0, 18:1, 18:2 and 18:3 acids were present besides of traces of 16:1 and 17:0. In contrast to neutral lipids the major acid of phospholipids is linoleic (53–58%), followed by oleic (8–24%) and linolenic acid (1–18%). The percentages of palmitic (4–8%) and stearic acids (tr.-1%) are small. Low lipid cells of series A differ from high lipid cells of series B by an increase of linolenic, and a decrease of linoleic acids, both in phosphatidyl choline and phosphatidyl ethanolamine.
  相似文献   

14.
This is the first report devoted to study of the hydrocarbon composition of the extract of buds of European birch Betula pendula (family Betulacea). We have identified saturated (C16 to C28, even number of carbon atoms) and unsaturated (linoleic and linolenic) fatty acids, β-caryophyllene, α-humulene, and the components of epicuticular waxes of cover scales, such as n-alkanes (C21 to C26), esters of fatty acids (C16 to C28, even number of carbon atoms), and fatty alcohols (C18 to C30, even number of carbon atoms). The gas chromatographic retention indices of all identified compounds have been determined.  相似文献   

15.
Lipids of Rhizopus arrhizus Fischer   总被引:1,自引:1,他引:0       下载免费PDF全文
The lipids of Rhizopus arrhizus Fischer mycelia and sporangiospores were extracted, isolated, and separated by thin-layer, liquid, and gas chromatography. Structural confirmations of the compounds were made by a gas chromatographmass spectrometer combination. The n-heptane fraction contained squalene (1%) as a major hydrocarbon constituent. Other major lipid classes detected were free fatty acids, naturally occurring methyl esters of fatty acids, triglycerides, sterols, and polar lipids. The polar lipids (44.4%) were found in the highest concentrations, and the triglycerides (22.1%), sterols (16.7%), and free fatty acids (11.7%) were present in lesser concentrations. This is the first report of naturally occuring methyl esters of long-chain fatty acids being present in fungal mycelium. There appears to be a preference for incorporation of unsaturated acids into the complex lipids, with the exception of the triglycerides. The major saturated fatty acids in the mycelium were palmitic (C(16)) and arachidic (C(20)), whereas the major unsaturated acids were oleic (C(18:1)) and linoleic (C(18:2)), respectively.  相似文献   

16.
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   

17.
In isolated tobacco leaves l-valine-U-14C gave rise to labeled even-numbered isobranched fatty acids containing 16 to 26 carbon atoms and iso C29, iso C31, and iso C33 paraffins. l-Isoleucine-U-14C on the other hand produced labeled odd-numbered anteiso C17 to C27 fatty acids and anteiso C30 and C32 paraffins. Trichloroacetic acid inhibited the incorporation of isobutyrate into C20 and higher fatty acids and paraffins without affecting the synthesis of the C16 and C18 fatty acids. Thus the very long branched fatty acids are biosynthetically related to the paraffins. In Senecio odoris leaves acetate-1-14C was incorporated into the paraffins (mainly n-C31) only in the epidermis although acetate was readily incorporated into fatty acids in the mesophyll tissue. Similarly only the epidermal tissue incorporated acetate into fatty acids longer than C18 suggesting that the epidermis is the site of synthesis of both paraffins and the very long fatty acids. In broccoli leaves n-C12 acid labeled with 14C in the carboxyl carbon and 3H in the methylene carbons was incorporated into C29 paraffin without the loss of 14C relative to 3H. Since n-C18 acid is known to be incorporated into the paraffin without loss of carboxyl carbon these results suggest that the condensation of C12 acid with C18 acid is not responsible for n-C29 paraffin synthesis in this tissue. Thus all the experimental evidence thus far obtained strongly suggests that elongation of fatty acids followed by decarboxylation is the most likely pathway for paraffin biosynthesis in leaves.  相似文献   

18.
The fatty acid pattern in hydrocarbon- and ketone-utilizing bacteria after growth on various substrates was examined. The fatty acid composition of one hydrocarbon-utilizing organism (Mycobacterium sp. strain OFS) was investigated in detail after growth on n-alkanes, 1-alkenes, ketones, and n-alcohols. n-Alkanes shorter than C13 or longer than C17 were not incorporated into cellular fatty acids without some degradation. Strain OFS incorporated C14 to C17 1-alkenes into cellular fatty acids as the ω-monoenoic fatty acid. Methyl ketones were incorporated into strain OFS after removal of one- or two-carbon fragments from the carbonyl end of the molecule. An organism isolated by enrichment on methyl ketones was incapable of n-alkane utilization but could grow on, although not incorporate, ketones or long chain n-alcohols into cellular fatty acids.  相似文献   

19.
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   

20.
Fatty acids in vesicular and leaf monogalactosyl diglycerides (MGDG) of citrus were studied. Vesicular MGDG contained front 94.4 to 97.3% C16, C16:1, C18:1, C18:2, and C18:3; whereas leaf MGDG contained ca 90% C18:3, 3% C16 and 1.8 to 9.5% C18:2. Species varied considerably in their percentages of vesicular C18:2, C18:3 and to a lesser degree, C16:1 and C18:1 fatty acids with lemons being the most distinctive. Branched fatty acids were present to the extent of 5.6% in vesicular and to only 0.1% in leaf MGDG.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号