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1.
The neutral and polar lipids of kenaf seeds of the variety Uzbetskii-1574 from the 1983 crop have been studied. The fatty acid compositions of six acyl-containing classes of neutral lipids have been established for the first time. The acids in the sn-2 positions of the triacylglycerols and of the main classes of phospholipids have been determined. The main triacylglycerol species are those in which the sn-2 position is esterified by linoleic acid.Institute of the Chemistry of Plant Substances of the UzSSR Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 558–564, September–October, 1986.  相似文献   

2.
Neutral lipids ofCitrullus vulgaris seeds   总被引:1,自引:0,他引:1  
The qualitative and quantitative compositions of the neutral lipids of watermelon seeds have been studied. The fatty acid compositions of the acyl-containing lipids have been determined. In the triacylglycerols the main forms are those in which the sn-2 position is substituted by linoleic acid.Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 494–495, May–June, 1995. Original article submitted May 30, 1994.  相似文献   

3.
A reversed-phase high-performance liquid chromatography (HPLC) method with on-line electrospray ionization/collision-induced dissociation/mass spectrometry (ESI/CID/MS) is presented for the regiospecific analysis of synthetic reference compounds of neutral ether lipids. The reference compounds were characterized by chromatographic retention times, full mass spectra, and fragmentation patterns as an aid to clarify the regiospecificity of ether lipids from natural sources. The results clearly show that single quadrupole mass spectroscopic analysis may elucidate the regiospecific structure of neutral ether lipids. Ether lipid reference compounds were characterized by five to six major ions in the positive ion mode. The 1-O-alkyl-sn-glycerols were analyzed as the diacetoyl derivative, and showed the [M - acetoyl](+) ion as an important diagnostic ion. The diagnostic ions of directly analyzed 1-O-alkyl-2-acyl-sn-glycerols and 1-O-alkyl-3-acyl-sn-glycerols were the [M - alkyl](+), [M + H - H(2)O](+) and [M + H](+) ions. Regiospecific characterization of the fatty acid position was evident from the relative ion intensities, as the sn-2 species had relatively high [M + H](+) ion intensities compared with [M + H - H(2)O](+), whereas the reverse situation characterized the sn-3 species. Furthermore, corresponding sn-2 and sn-3 species were separated by the chromatographic system. However, loss of water was promoted as fatty acid unsaturation was raised, which may complicate interpretation of the mass spectra. The diagnostic ions of directly analyzed 1-O-alkyl-2,3-diacyl-sn-glycerols were the [M - alkyl](+), [M - sn-2-acyl](+) and [M - sn-3-acyl](+) ions. Regiospecific characterization of the fatty acid identity and position was evident from the relative ion intensities, as fragmentation of the sn-2 fatty acids was preferred to the sn-3 fatty acids; however, loss of fatty acids was also promoted by higher degrees of unsaturation. Therefore, both structural and positional effects of the fatty acids affect the spectra of the neutral ether lipids. Fragmentation patterns and optimal capillary exit voltages are suggested for each neutral ether lipid class. The present study demonstrates that reversed-phase HPLC and positive ion ESI/CID/MS provide direct and unambiguous information about the configuration and identity of molecular species in neutral 1-O-alkyl-sn-glycerol classes.  相似文献   

4.
The lipid complex of the seeds ofPeganum harmala (fam. Zygophyllaceae) has been investigated. The qualitative and quantitative compositions of the neutral lipids and the phospholipids have been studied. The fatty acid compositions of the acyl-containing lipids have been determined and it has been shown that in the triacylglycerols and phosphatidylethanolamines the sn-2 position is esterified mainly by linoleic acid. Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 625–627, November–December, 1992.  相似文献   

5.
The lipid complex of the seeds ofPeganum harmala (fam. Zygophyllaceae) has been investigated. The qualitative and quantitative compositions of the neutral lipids and the phospholipids have been studied. The fatty acid compositions of the acyl-containing lipids have been determined and it has been shown that in the triacylglycerols and phosphatidylethanolamines the sn-2 position is esterified mainly by linoleic acid.Institute of Chemistry of Plant Substances, Uzbekistan Academy of Sciences, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 625–627, November–December, 1992.  相似文献   

6.
The acyl-containing classes of neutral lipids have been studied and the amounts of phospholipids and their fatty acid composition have been determined in the pericarps and seeds ofZizyphus jujuba. The fatty oil of the seeds contains oleic acid while in the neutral lipids of the pericarps the main acid is the biologically active palmitoleic. In the qualitative respect, the set of phospholipids in the seeds is more diverse, while the main classes quantitatively in both parts of the fruit are phosphatidylcholines and phosphatidylglycerols. The phospholipids of the pericarps are more saturated than those of the seeds.Institute of Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 21–24, January–February, 1990.  相似文献   

7.
An innovative procedure to separate the 3 isomeric sn-monoacylglycerols (MAG) classes (sn-1-, sn-2-, sn-3-MAG) is described. MAGs, obtained by chemical deacylation of triacylglycerols (TAGs), have been derivatized with (S)-(+)-1-(1-naphtyl)ethyl-isocyanate, and the resulting urethane derivatives have been separated by normal-phase high-performance liquid chromatography. This procedure allows resolution as diasteroisomers of the 2 enantiomeric classes (sn-1-MAG and sn-3-MAG), without the need of a chiral column, and to separate also the isomeric sn-2-MAG class; moreover, by introducing a chromophoric moiety, this reagent makes possible the ultraviolet detection of the analyte molecules. This procedure has been used to obtain the stereospecific analysis of the TAG fraction of extra virgin olive oil samples. The use of a nondestructive detector permitted the collection of the individual urethane classes; the fatty acid composition of each was determined by high-resolution gas chromatography, obtaining directly from the data the fatty acid distribution within each sn- position of TAGs. To validate this new method, the results have been compared with those obtained by 2 other procedures for TAG stereospecific analysis, and the obtained results were satisfactory since the proposed method gave data very similar to the other procedures.  相似文献   

8.
The composition and amounts of various classes of lipids of the seeds of Hibiscus sp. have been investigated. Seven classes of neutral lipids, five of phospholipids, and five of glycolipids have been identified and their fatty-acid and triglyceride compositions have been established. The presence has been shown of 16 main types of triacylglycerols and 25 types of epoxyacyldiacylglycerols. An epoxy-18.0 and an epoxy-18:1 acid in a combined amount of 1.4% have been detected among the acids of the free lipids, together with 8.1% of cyclopropenoid acids.Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 40–44, January–February, 1995. Original article submitted October 24, 1994.  相似文献   

9.
The surface lipids of the coat and the lipids of the kernel of the seeds of a wild form of the medium-fibered cotton plantGossypium mexicanum var.nervosum have been studied in comparison with cultured species. Using the methods of CC, TLC, and GLC, and UV and mass spectrometry, in the cuticular lipids ofG. mexicanum three classes of neutral lipids have been detected, and in the kernel lipids 10 classes of neutral lipids, 2 classes of glycolipids, and 7 classes of phospholipids. The structures of the epoxyacyl-, hydroxyacyl-, and diacylglycerols of the kernel have been established. The greatest differences between the seeds of the wild form of the cotton plant and the cultured species are the greater weight of the seed coat, the presence in it of a considerable amount of the 18:1 and of medium-molecular-weight fatty acids, and a higher level in the kernel of gossypol pigments, polar lipids, and acylglycerols containing the 18:2 acid.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 57–62, January–February, 1987.  相似文献   

10.
The lipid complex of the seeds ofHeracleum lehmannianum B. has been studied. The qualitative and quantitative compositions of the neutral lipids and the phospho- and glycolipids, and the fatty acid compositions of the acyl-containing classes of lipids have been determined. It has been shown that the neutral and the polar lipids differ considerably from one another with respect to the level of certain fatty acids. The position-species compositions of the TAGS and of the main components of the phospholipids have been calculated from the results of lipolytic hydrolysis.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 89 14 75. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 10–14, January–February, 1996. Original article submitted June 12, 1995.  相似文献   

11.
Lipid components of the seeds ofViburnum opulus (Caprifoliaceae family) were investigated. The neutral lipids consist of eight classes, the glycolipids consist of three classes, and the phospholipids contain seven classes. The fatty-acid contents of all of the acyl-containing lipids were determined. The 18∶2 fatty acid is the main component of all the lipid fractions. The content of saturated acids is greater in the glycolipids and phospholipids. The lipophilic components, higher fatty alcohols and sterols, were identified.  相似文献   

12.
Composition of the neutral lipids of Chlorella vulgaris   总被引:1,自引:0,他引:1  
Summary The qualitative and quantitative compositions of the neutral lipids and the fatty-acid composition of the individual classes of neutral lipids isolated from fresh, freeze-dried, and air-dry cells of the algaChlorella vulgaris have been investigated.The presence of natural fatty acid methyl esters in the lipid extract of the fresh and air-dry chlorella cells has been established.It has been shown that the fatty acid methyl ester fraction is enriched with palmitic acid as compared with the triglyceride and free fatty acid fractions.The main unsaturated acids of the chlorella lipids contain the first double bond in the 9 position.Division of Microbiology of the Academy of Sciences of the Uzbek SSR, Tashkent. Institute of the Chemistry of Plant Substances, Academy of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 49–53, January–February, 1978.  相似文献   

13.
By chromatographic methods, about 30 groups of various lipid compounds belonging to the classes of neutral lipids, glycolipids, and phospholipids have been identified from the fruit of the fig tree. The main groups are triacylglycerols, free and esterified sterols, mono- and digalactosyldiglycerides, ceramide oligosides, cerebrosides, esterified sterol glycosides, and phosphatidylglycerols. In the fatty acid composition, linoleic, linolenic, oleic, and palmitic acids predominated (>90%).  相似文献   

14.
Lysoglycerophosphocholine lipids (lyso-GPC) are important intermediates in the synthesis and metabolism of glycerophosphocholine lipids which are major components of the cellular lipid bilayer. Significant differences in the collisional induced decomposition (CID) behavior were observed for each of the four different subtypes of lyso-GPC in both positive and negative ions. A major difference was observed in the initial CID product ions derived from lyso-GPC [M + H]+ with the loss of water that was very abundant for acyl lyso-GPC which have a fatty acid ester substituent at either the sn-1 or sn-2 positions. Loss of neutral water was not very prominent in the case of plasmenyl and plasmanyl lyso-GPC species. The mechanism responsible for this difference in behavior of lyso-GPC subtypes was consistent with a higher proton affinity of carboxyl carbonyl oxygen atoms and vinyl ether oxygen atoms found in acyl and plasmenyl lyso-GPC lipids, respectively, as compared to the carbinol oxygen atom common to all lyso-GPC species. Collisional activation of lyso-GPC negative ions [M - 15]- also revealed distinctive differences in product ions derived from acyl and ether lyso-GPC species. The acyl compounds showed the facile elimination of a highly stable carboxylate anion, whereas plasmenyl species underwent fragmentation with loss of a neutral aldehyde, likely a result of rearrangement involving the double bond in the vinyl ether moiety. The alkyl ether species (plasmanyl lyso-GPC lipids) did not undergo either decomposition reaction observed for the other lyso-GPC subtypes which permitted differentiation of acyl, plasmenyl, and plasmanyl lyso-GPC subtypes.  相似文献   

15.
The composition of ethanolic (I) and gasoline (II) extracts of the cultivated microalgaChlorella vulgaris has been studied. With the aid of CC, TLC, qualitative reactions, GLC, and UVS the following classes of compounds have been detected in them. From the neutral lipids: hydrocarbons, carotenoids, traces of sterols and their esters, fatty acid esters, tri- and diacylglycerols, free fatty acids, and chlorophylls; and from the polar lipids: di- and monogalactosylglycerols, phosphatidylethanolamine, lecithin, phosphatidylinositol, phosphatidylserine, and three sphingosine bases. The polar lipids I and II made up 52.4 and 50.2% of the total, respectively. As compared with extract I, extract II was somewhat enriched with neutral lipids, including provitamins of the A group and vitamins of the F group. In the fatty acids of chlorella, 19 components were detected, the main ones being the 16:0 acid and 18:2 and 18:3 acids.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 284–288, May–June, 1986.  相似文献   

16.
The composition of the neutral lipids of leaves of a cotton plant of the wilt-resistant variety 175-F, the set of components in the fatty acid composition of the lipid classes, and the partial structures of the triacylglycerides have been determined. The changes taking place in the composition and structure of these lipids on artificial infection of the plant by the fungal pathogenVerticillium dahliae have been elucidated.  相似文献   

17.
Characterisation of phospholipids was achieved using collision-induced dissociation (CID) with an ion-trap mass spectrometer. The product ions were compared with those obtained with a triple quadrupole mass spectrometer. In the negative ion mode the product ions were mainly sn-1 and sn-2 lyso-phospholipids with neutral loss of ketene in combination with neutral loss of the polar head group. Less abundant product ions were sn-1 and sn-2 carboxylate anions. CID using a triple quadrupole mass spectrometer, however, gave primarily the sn-1 and sn-2 carboxylate anions together with lyso-phosphatidic acid with neutral loss of water. For the ion trap a charge-remote-type mechanism is proposed for formation of the lyso-phospholipid product ions by loss of alpha-hydrogen on the fatty acid moiety, electron rearrangement and neutral loss of ketene. A second mechanism involves nucleophilic attack of the phosphate oxygen on the sn-1 and sn-2 glycerol backbone to form carboxylate anions with neutral loss of cyclo lyso-phospholipids. CID (MS(3) and MS(4)) of the lyso-phospholipids using the ion-trap gave the same carboxylate anions as those obtained with a triple quadrupole instrument where multiple collisions in the collision cell are expected to occur. The data demonstrate that phospholipid species determination can be performed by using LC/MS(n) with an ion-trap mass spectrometer with detection of the lyso-phospholipid anions. The ion-trap showed no loss in sensitivity in full scan MS(n) compared to multiple reaction monitoring data acquisition. In combination with on-line liquid chromatography this feature makes the ion-trap useful in the scanning modes for rapid screening of low concentrations of phospholipid species in biological samples as recently described (Uran S, Larsen A, Jacobsen PB, Skotland T. J. Chromatogr. B 2001; 758: 265).  相似文献   

18.
The compositions and the amounts of various groups of liposoluble compounds in the component elements of the fruits ofCitrus unshiu Marc. [satsuna variety of mandarin orange] — the flavedo, the albedo, the membrane, and the flesh — have been determined by chromatographic and chemical methods. About 30 groups of lipid compounds belonging to the classes of neutral lipids and glyco- and phospholipids have been identified and characterized. The fatty-acid compositions of the main classes of lipids have been studied. About 30 different carotenoids have been determined in the various elements of the satsuma orange.M. V. Lomonosov Odessa Technological Institute of the Food Industry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 342–348, May–June, 1989.  相似文献   

19.
The chemical composition of lipids from six human brains (60–73 years) is reported. The total lipids out of cortex, white matter, diencephalon and cerebellum, pons, and medulla oblongata have been isolated and the neutral lipids have been separated in cerebrosides, sphingomyelines, and lecithins. The highest amount of pure lipids is found in the white matter, the lowest in the cortex. The relation of neutral lipids to acid lipids as well as the amount of cholesterol are about equal for all regions. The white matter shows more cerebrosides and sphingomyelines than the cortex, the opposite being the case for lecithins. The differences are strongly significant. The fatty acids out of the different pure lipid fractions have been analysed as esters by gas chromatography. Stearic and lignoceric acid, and cerebronic and hydroxy nervonic acid respectively are main components of cerebrosides, with only little differences for the different brain regions. The fatty acids of sphingomyelines consist mainly of stearic and nervonic acid; in the white matter these two acids are present about in the same quantity, whereas stearic acid dominates in the cortex and the other sections. Lecithins contain above all palmitic and oleic acid. The amount of the latter in the white matter is higher than that of palmitic acid.  相似文献   

20.
Summary The compositions of the neutral lipids of the mycelium and of the culture liquid from the pathogenic fungusVerticillium dahliae Kleb. have been investigated for the first time. The fatty-acid compositions of the main lipid fractions and the glyceride composition of the triglyceride fraction have been determined. The main acids of all the fractions are the 16:0 and 18:1 acids and in the triglyceride fraction, additionally, the 18:2 acid. Diisobutyl phthalate has been found in the combined neutral lipids of the fungal mycelium.V. I. Lenin Tashkent State University, Institute of the Chemistry of Plant Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 431–435, July–August, 1976.  相似文献   

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