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1.
Zhou L Zhao M Ennahar S Bindler F Marchioni E 《Analytical and bioanalytical chemistry》2012,403(1):291-300
A liquid chromatographic–electrospray ionization–tandem mass spectrometric (LC–ESI–MS2) method has been developed for determination of the molecular species of phosphatidylethanolamine (PE) in four food matrices
(soy, egg yolk, ox liver, and krill oil). The extraction and purification method consisted of a pressurized liquid extraction
procedure for total lipid (TL) extraction, purification of phospholipids (PLs) by adsorption on a silica gel column, and separation
of PL classes by semi-preparative normal-phase HPLC. Separation and identification of PE molecular species were performed
by reversed-phase HPLC coupled with electrospray ionization tandem mass spectrometry (ESI–MS2). Methanol containing 5 mmol L−1 ammonium formate was used as the mobile phase. A variety of PE molecular species were detected in the four food matrices.
(C16:0–C18:2)PE, (C18:2–C18:2)PE, and (C16:0–C18:1)PE were the major PE molecular species in soy. Egg yolk PE contained (C16:0–C18:1)PE,
(C18:0–C18:1)PE, (C18:0–C18:2)PE, and (C16:0–C18:2)PE as the major molecular species. Ox liver PE was rich in the species
(C18:0–C18:1)PE, (C18:0–C20:4)PE, and (C18:0–C18:2)PE. Finally, krill oil which was particularly rich in (C16:0(alkyl)–C22:6(acyl))plasmanylethanolamine
(PakE), (C16:0–C22:6)PE, and (C16:0–C20:5)PE, seemed to be an interesting potential source for supplementation of food with
eicosapentaenoic acid and docosahexaenoic acid. 相似文献
2.
Rabagny Y Herrmann W Geisel J Kirsch SH Obeid R 《Analytical and bioanalytical chemistry》2011,401(3):891-899
We describe a fast and robust ultra performance liquid chromatography tandem mass spectrometry method for the quantification
of phospholipid (PL) species in EDTA-plasma samples. We quantified total phosphatidylcholine (PC), phosphatidylethanolamine
(PE), lysophosphatidylcholine (LPC), and sphingomyelin (SM) and several species within these classes using one or two external
calibrators and one internal standard for each class. Inter-assay coefficients of variation were <10% for the most abundant
species and <20% for all quantified PC, LPC, and SM species and the three most abundant PE species. Coefficients of linear
regression were R
2 > 0.98. Mean recoveries were between 83% and 123%. The limits of detection were 0.37 μmol/L for PC, 4.02 μmol/L for LPC,
3.75 μmol/L for PE, and 0.86 μmol/L for SM. Quantification was linear over the physiological ranges for PE, LPC, and SM and
up to 500 μmol/L for PC. The concentrations of PLs in the plasma of healthy donors yielded results that were comparable with
those of previous works. 相似文献
3.
S. V. Khotimchenko 《Chemistry of Natural Compounds》2005,41(3):285-288
The composition of lipids and fatty acids from the red alga Gracilaria verrucosa, for which a high content of 20:4n-6 acid is typical, was studied. The principal lipids were digalactosyldiacylglycerides, phosphatidylcholines (PC), monogalactosyldiacylglyderides (MGDG), and sulfoquinovosyldiacylglycerides, the fraction of each was approximately the same. Sphingophospholipids, inositephosphoceramides, were identified among the polar lipids. Each lipid class differed in the ratio of fatty acids (FA). The FA of all glycerolipids contained 20:4n-6 acid but its concentration was greatest in MGDG and PC, 67.2% and 56.5% of the acid mass.__________Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 230–232, May–June, 2005. 相似文献
4.
Qualitative and quantitative profiling of six different categories of urinary phospholipids (PLs) from patients with prostate
cancer was performed to develop an analytical method for the discovery of candidate biomarkers by shotgun lipidomics method.
Using nanoflow liquid chromatography–electrospray ionization–tandem mass spectrometry, we identified the molecular structures
of a total of 70 PL molecules (21 phosphatidylcholines (PCs), 11 phosphatidylethanolamines (PEs), 17 phosphatidylserines (PSs),
11 phosphatidylinositols (PIs), seven phosphatidic acids, and three phosphatidylglycerols) from urine samples of healthy controls
and prostate cancer patients by data-dependent collision-induced dissociation. Identified molecules were quantitatively examined
by comparing the MS peak areas. From statistical analyses, one PC, one PE, six PSs, and two PIs among the PL species showed
significant differences between controls and cancer patients (p < 0.05, Student’s t test), with concentration changes of more than threefold. Cluster analysis of both control and patient groups showed that
18:0/18:1-PS and 16:0/22:6-PS were 99% similar in upregulation and that the two PSs (18:1/18:0, 18:0/20:5) with two PIs (18:0/18:1
and 16:1/20:2) showed similar (>95%) downregulation. The total amount of each PL group was compared among prostate cancer
patients according to the Gleason scale as larger or smaller than 6. It proposes that the current study can be utilized to
sort out possible diagnostic biomarkers of prostate cancer. 相似文献
5.
S. V. Isai N. G. Busarova A. L. Drozdov Yu. N. El’kin 《Chemistry of Natural Compounds》2007,43(4):387-390
The composition of lipids and their fatty acids in tissues of scalp, gonads, and internal organs of the sand dollar Scaphechinus mirabilis was determined using one-and two-dimensional TLC and GC-MS. Lipids of S. mirabilis scalp consisting of several neutral and phospholipids were characterized for the first time. A significant quantity of eicosapentaenoic
acid (20:5) was found in scalp lipids.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 320–323, July–August, 2007. 相似文献
6.
S. A. Rod’kina 《Chemistry of Natural Compounds》2007,43(5):515-518
The fatty-acid (FA) composition of total lipids from the Okhotsk sea marine sponge Forcepia uschakowi was studied. A total of 56 acids were identified by GC and GC—MS. The principal saturated acids were 16∶0 and 18∶0. The main
monoene acid was 15-Me-24∶1(14), which was observed for the first time in sponge lipids. Polyunsaturated acids represented
of 64.1% of the total FA of F. uschakowi. Of these, the principal ones were non-methylene-separated acids 26∶2(5,9) and 26∶3(5,9,19), which are typical of sponges,
and bromo-acid 6-Br-26∶2(5,9).
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 422–424, September–October, 2007. 相似文献
7.
Beate Fuchs Annabell Bischoff Rosmarie Süß Kristin Teuber Martin Schürenberg Detlev Suckau Jürgen Schiller 《Analytical and bioanalytical chemistry》2009,395(8):2479-2487
Phospholipids (PL) are increasingly analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass
spectrometry (MS). As in the case of polar molecules, however, the careful selection of the matrix is crucial for optimum
results. 9-Aminoacridine (9-AA) was recently suggested as the matrix of choice to analyze PL mixtures because of (a) the improved
sensitivity and (b) the reduction of suppression effects compared to other matrices. However, the distinction of phosphatidylcholine
(PC) and phosphatidylethanolamine (PE) in the negative ion mode is obscured as PC is also detectable as –CH3+ ion if 9-AA is used as matrix. This may result in the erroneous assignment of PC as a PE species. Using an organic extract
from hen egg yolk as example it will be shown that the contribution of PC must be taken into consideration if the negative
ion mass spectra are used to evaluate the fatty acyl compositions of PE mixtures. 9-AA can as well be used in hyphenated thin-layer
chromatography (TLC)-MALDI-TOF MS where PC and PE are chromatographically well separated for unequivocal assignments.
相似文献
8.
Cardiolipin (CL) plays an essential role as a marker for cell apoptosis. Quantitative detection of phospholipids (PLs) by
UV absorbance is problematic due to the presence of few double bonds in the structure. Although 10-N-nonyl acridine orange (NAO) has been utilized for fluorescent visualization of liposomes and mitochondria through its interaction
with CL, in this work, we have developed a specific fluorescent method for CL in solution using NAO. The interaction of sodium n-dodecyl sulfate (SDS), used to treat cells prior to lipid extraction, and other PLs found in cell membranes such as phosphatidic
acid (PA), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), phosphatidiylserine (PS), and
sphingomyelin (SM) with NAO is investigated. The fluorescence intensity of the 0.5 μM NAO signal is strongly quenched by SDS
below 25% methanol in water but with a methanol content above 50%, no quenching of NAO by SDS is observed. No fluorescence
quenching of NAO with a 50% methanol/50% water solvent by the previously mentioned PLs or 4–20 μM cholesterol with the exception
of PG at above 8 μM is noted. Using this 50% methanol/50% water solvent, the fluorescence signal due to the NAO–CL interaction
is quite stable from 3 to at least 15 min. With excitation and emission wavelengths set at 518 and 530 nm, respectively, 20 μM
NAO provides an inverse linear fluorescence response at 0.2–10 μM CL with a correlation coefficient of 0.9929. The detection
limit is 0.2 μM and the limit of quantification is 0.6 μM. Structurally analogous acridine orange and phenosafranin dyes are
less effective as fluorescent probes for CL. The CL in the whole cell and membrane samples is quantitatively determined by
standard addition to range from 0.2 to 1.5 μM. The level of CL in cell membrane samples, previously subjected to staurosporine
which initiates cell apoptosis, is increased but not significantly through use of the t-test. 相似文献
9.
An ultra-performance liquid chromatography-tandem mass spectrometry method was developed, optimised and validated for the
quantification of synthetic folic acid (FA), also called pteroyl-l-glutamic acid or vitamin B9 and naturally occurring 5-methyltetrahydrofolate (5-MTHF) found in folate-fortified breads. Optimised
sample preparation prior to analysis involved addition of 13C5 labelled internal standards, treatments with α-amylase and rat serum, solid-phase extraction using aromatic-selective cartridges
and ultra-filtration. Analytes were separated on a Waters ACQUITY HSS T3 column during a 6-min run and analysed by positive
ion electrospray selected reaction monitoring MS/MS. Standard calibration curves for the two analytes were linear over the
range of 0.018–14 μg FA/g of fresh bread (r
2 = 0.997) and 9.3–900 ng 5-MTHF/g of fresh bread (r
2 = 0.999). The absolute recoveries were 90% and 76% for FA and 5-MTHF, respectively. Intra-day coefficients of variation were
3% for FA and 18% for 5-MTHF. The limit of detection was 9.0 ng/g for FA and 4.3 ng/g for 5-MTHF, determined using pre-extracted
tapioca starch as the blank matrix. The assay is rugged, fast, accurate and sensitive, applicable to a variety of food matrices
and is capable of the detection and quantification of the naturally occurring low levels of 5-MTHF in wheat breads. The findings
of this study revealed that the FA range in Australian fortified breads was 79–110 μg/100 g of fresh bread and suggest that
the flour may not have the mandated FA fortification level (200–300 μg/100 g of flour), though this cannot be determined conclusively
from experimental bread data alone, as variable baking losses have been documented by other authors. 相似文献
10.
Shih-Yuan Lin Ying-Chung Chen Chih-Ming Wang Chan-Chih Liu 《Journal of Solid State Electrochemistry》2008,12(11):1481-1486
Electrochromic titanium oxide (TiO2) films were deposited on ITO/glass substrates by chemical solution deposition (CSD). The stock solutions were spin-coated
onto substrates and then heated at various temperatures (200–500 °C) in various oxygen concentrations (0–80%) for 10 min.
The effects of the processing parameters on the electrochromic properties of TiO2 films were investigated. X-ray diffraction measurements demonstrated that the amorphous TiO2 films were crystallized to form anatase films above 400 °C. The electrochromic properties and transmittance of TiO2 films were measured in 1 M LiClO4–propylene carbonate (PC) non-aqueous electrolyte. An amorphous 350 nm-thick TiO2 film that was heated at 300°C in 60% ambient oxygen exhibited the maximum transmittance variation (ΔT%), 14.2%, between the bleached state and the colored state, with a ΔOD of 0.087, Q of 10.9 mC/cm2, η of 7.98 cm2/C and x in Li
x
ClO4 of 0.076 at a wavelength (λ) of 550 nm. 相似文献
11.
V. P. Korolev O. A. Antonova N. L. Smirnova A. V. Kustov 《Journal of Thermal Analysis and Calorimetry》2009,96(3):903-910
The heats of solution of tetrabutylammonium bromide have been measured in mixtures of formamide (FA) with methanol (MeOH)
and ethylene glycol (EG) at 313.15 K by calorimetric method. The standard enthalpies of solution in binary mixtures have been
extrapolated to infinite dilution by Redlich–Rosenfeld–Meyer type equation using the literary data at 298.15 K and the present
paper data at 313.15 K. The Debye–Hückel limiting law slope A
H required for calculation of the ∆sol
H
0 value has been obtained with application the new additive scheme of determination of the physic-chemical characteristics
of binaries. The scheme is tested on the example of Bu4NBr solutions in FA–MeOH mixture at 298.15 K. Its application yields the ∆sol
H
0 value very closed on the ones determined with the real (non-additive) characteristics of binaries. The standard enthalpies
of solution extrapolated by Redlich–Rosenfeld–Meyer type equation are in a good agreement with the ones computed in terms
of the Debye–Hückel theory in the second approximation. The heat capacities characteristics of Bu4NBr have been calculated in H2O–FA, MeOH–FA and EG–FA mixtures using the literary and present data. The sequence of solvents H2O > FA > EG > MeOH located on their ability to solvophobic solvation found by us earlier for enthalpic characteristics is
confirmed by the ∆C
p
0 values. The comparison of thermochemical characteristics of Bu4NBr solutions in aqueous and non-aqueous mixtures containing FA has been carried out. The own structure of water remains in
the region of small additions of formamide to co-solvents. It considerably differs the H2O–FA mixture from the investigated non-aqueous systems. 相似文献
12.
G. I. Kovylyaeva G. A. Bakaleinik I. Yu. Strobykina V. I. Gubskaya R. R. Sharipova V. A. Al’fonsov V. E. Kataev A. G. Tolstikov 《Chemistry of Natural Compounds》2007,43(1):81-85
A new laboratory method for isolating the glycosides stevioside and rebaudiosides A and C from leaves of Stevia rebaudiana was proposed. According to HPLC, the glycoside contents in plants grown in Russia (Voronezh Oblast’) and Ukraine (Crimea)
were 5–6% (stevioside) and 0.3–1.3% (rebaudiosides A and C).
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–71, January–February, 2007 相似文献
13.
The sterol composition of macromycete fungus Laetiporus sulphureus was analyzed by GC-MS. The fungus contained mainly C16 to C20 fatty acids, C16 to C24 fatty acid ethyl esters, and C28, C29,
and C30, Δ5, Δ7, and Δ5,7 conventional sterols, and in minor amounts Δ0 analogues with saturated and unsaturated side chains. Moreover, ergosterol peroxide and cerevisterol were identified. This
sterol pattern was compared with those of other members of the family Polyporaceae reported in the literature.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 170–172, March–April, 2009. 相似文献
14.
Li Wang Shuguang Jian Peng Nan Jimei Liu Yang Zhong 《Chemistry of Natural Compounds》2005,41(5):491-493
The chemical constituents of leaf oils of Elephantopus scaber L. from 12 locations in Southern China, including three provinces and Hong Kong, were investigated using GC/MS. A total of
24 compounds were detected, of which 20 were identified by their mass spectra fragmentation patterns. The major compounds
include hexadecanoic acid (8.19–39.22%), octadecadienoic acid (trace - 29.22%), five alkane homologues, i.e., n-tetradecane
(1.19–5.26%), n-pentadecane (3.22–12.05%), n-hexadecane (2.38–16.26%), n-heptadecane (2.48–15.32%), and n-octadecane (1.39–9.59%),
as well as tetramethylhexadecenol (2.06–4.31%). Hierarchical cluster analysis classified the leaf oils into two groups. Two
main chemotypes of leaf oils in E. scaber were thus identified, one rich in hexadecanoic acid and octadecadienoic acid, and the other rich in the five alkane homologues.
__________
Published in Kimiya Prirodnikh Soedinenii No. 5, pp. 403–404, September–October, 2005. 相似文献
15.
Kh. T. Mirzaazimova S. D. Gusakova A. I. Glushenkova 《Chemistry of Natural Compounds》1999,35(6):616-618
The content and composition by class and fatty acid of neutral (NL), glyco- (GL), and phospholipids (PL) in leaves ofEphedra equizetina Bunge (Ephedraceae) are determined. The acid composition of NL, GL, and PL includes saturated 12∶0–32∶0 acids and unsaturated
15∶1, 16∶1, 18∶1, 18∶2, and 18∶3 acids. Unsaponified components of the total lipids also contained biologically active substances
such as α-tocopherol, carotenoids, high-molecular-weight fatty alcohols, triterpenes, and sterols.
Academician S. Yu. Yunusov Institute of the Chemistry of Plant Substances. Academy of Sciences of the Republic of Uzbekistan,
Tashkent, fax (371) 120 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 718–721, November–December, 1999. 相似文献
16.
The root of Carlina acanthifolia All. (Asteraceae) contained 1.0% of essential oil (expressed in g per 100 g of dried plant material). Using GC and GC/MS,
nine components were identified (100% of total oil). The structure of benzyl 2-furylacetylene (carlina oxide), which is the
principal component of the oil (91.5%), was spectrometrically identified.
__________
Published in Khimiya Prirodnykh Soedinenii, No. 4, pp. 331–332, July–August, 2005. 相似文献
17.
Aerial parts of Sideritis cilicica Boiss. & Bal. and Sideritis bilgerana P.H. Davis (Lamiaceae) were hydrodistilled to obtain essential oils that were then analyzed by GC and GC/MS. β-Pinene (39%),
α-pinene (28%), and β-phellandrene (20%) were the main components in the oil of S. cilicica, while β-pinene (48%), and α-pinene (32%) were the major constituents in the oil of S. bilgerana. The antimicrobial activities of the oils were evaluated by using the microdilution broth method. Both of the oils showed
good inhibitory effects on C. albicans.
__________
Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 559–561, November–December, 2005. 相似文献
18.
T. Nochaiya W. Wongkeo K. Pimraksa A. Chaipanich 《Journal of Thermal Analysis and Calorimetry》2010,100(1):101-108
The effect of calcium hydroxide (CH) on the properties of Portland–fly ash cement pastes, at up to high-volume fly ash mixes
has been investigated using normal consistency, setting time, compressive strength, thermal analysis and scanning electron
microscope. CH as an additive material (5 and 10 wt%), lignite fly ash (FA) up to 50 wt% was used to produce Portland cement
(PC)–FA–CH pastes at w/PC + FA ratio of 0.5. Water requirement for normal consistency was found to increase with increasing
CH content while a decrease in initial setting time was found. Furthermore, the compressive strengths of all FA mixes with
CH were found to be higher than the mixes without CH. Thermal analysis and scanning electron microscope were used to study
the hydration of PC–FA–CH system. The results showed that the first phase transition detected by thermal analyses was attributed
to ettringite, calcium silicate hydrate, gehlenite hydrate and was found to be higher in PC–FA–CH mixes than in pure Portland–FA
cement paste resulting in an increase in compressive strength. Moreover, the hydration phases were also found to increase
with increasing curing time. Overall, the results show that the additional of 5 wt% CH in Portland–FA mixes especially at
high-volume FA mixes was found to accelerate FA pozzolanic reaction at early ages (7 and 28 days), resulting to an increase
in compressive strength. 相似文献
19.
Galactomannans with galactose:mannose ratios 1:1.48 and 1:1.33, [α]D +67.9 and +76.4°, [η] 870.3 and 1337.1 mL/g, and molecular weights 999 and 1549 kDa, respectively, were isolated in 0.59
and 4.65% yields (of seed mass) from seeds of Astragalus alpinus and A. tibetanus (Fabaceae). Physicochemical methods (CrO3 oxidation; methylation–GC/MS; IR, NMR, and 13C spectroscopy) found that the main polysaccharide chain consisted of 1,4-β-D-mannopyranose units substituted 67.5% (A. alpinus) and 75.2% (A. tibetanus) at the C-6 position by single α -D-galactopyranose units. The contents of mannobiose blocks Man–Man, (Gal)Man–Man/Man–Man(Gal), and (Gal)Man–Man(Gal) variously
substituted with galactose were according to 13C NMR spectroscopy 15.9, 55.5, and 28.6% in A. alpinus galactomannan and 9.9, 42.3, and 47.8% in A. tibetanus galactomannan. 相似文献
20.
Davide Coniglio Mariachiara Bianco Giovanni Ventura Cosima D. Calvano Ilario Losito Tommaso R. I. Cataldi 《Molecules (Basel, Switzerland)》2021,26(15)
The lipidome of a brown seaweed commonly known as wakame (Undaria pinnatifida), which is grown and consumed around the world, including Western countries, as a healthy nutraceutical food or supplement, was here extensively examined. The study was focused on the characterization of phospholipids (PL) and glycolipids (GL) by liquid chromatography (LC), either hydrophilic interaction LC (HILIC) or reversed-phase LC (RPLC), coupled to electrospray ionization (ESI) and mass spectrometry (MS), operated both in high and in low-resolution mode. Through the acquisition of single (MS) and tandem (MS/MS) mass spectra more than 200 PL and GL of U. pinnatifida extracts were characterized in terms of lipid class, fatty acyl (FA) chain composition (length and number of unsaturations), and regiochemistry, namely 16 SQDG, 6 SQMG, 12 DGDG, 5 DGMG, 29 PG, 8 LPG, 19 PI, 14 PA, 19 PE, 8 PE, 38 PC, and 27 LPC. The FA (C16:0) was the most abundant saturated acyl chain, whereas the monounsaturated C18:1 and the polyunsaturated C18:2 and C20:4 chains were the prevailing ones. Odd-numbered acyl chains, iJ., C15:0, C17:0, C19:0, and C19:1, were also recognized. While SQDG exhibited the longest and most unsaturated acyl chains, C18:1, C18:2, and C18:3, in the sn-1 position of glycerol, they were preferentially located in the sn-2 position in the case of PL. The developed analytical approach might pave the way to extend lipidomic investigations also for other edible marine algae, thus emphasizing their potential role as a source of bioactive lipids. 相似文献