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1.
Separation and analysis of phospholipids in different foods with a light-scattering detector 总被引:1,自引:0,他引:1
Maria Fiorenza Caboni Simonetta Menotta Giovanni Lercker 《Journal of the American Oil Chemists' Society》1996,73(11):1561-1566
A method for the separation of phospholipids (PL) from total lipids by solid-phase extraction (SPE) with reversephase C8 cartridges is described. The method was validated with a standard mixture of PL and applied to natural food matrixes, such
as egg, chicken meat, salami, and ripened cheese. The recovery of PL ranged between 93 and 99.7% and was evaluated by an organic
phosphorus spectrophotometric determination. The egg powder PL fraction obtained by SPE contained about 20% (w/w) nonpolar
PL material when 100–150 mg of lipids were loaded onto the cartridge. Higher percentages of nonphospholipid components (30–43%)
were obtained when the amount of lipids loaded was below or above the 100–150 mg range. The purified PL fractions were analyzed
by high-performance liquid chromatography (HPLC) with an evaporative light-scattering detector. Good HPLC performance was
observed even with low-purity SPE fractions (43% nonphospholipid material). 相似文献
2.
Seong Chea Chua Chin Ping Tan Oi Ming Lai Kamariah Long Hamed Mirhosseini Badlishah Sham Baharin 《European Journal of Lipid Science and Technology》2008,110(4):334-340
Palm‐pressed fiber (PPF) is a by‐product of palm oil milling and it has been found to contain a high percentage of phospholipids (PL). The aim of this work was to evaluate the best solid‐phase extraction (SPE) method to purify PL from PPF. The purified PL were analyzed using high‐performance liquid chromatography (HPLC) with an evaporative light‐scattering detector (ELSD). The oil was extracted from PPF using the Folch method and classes of PL were purified using SPE. Different solvent phases and normal‐phase SPE cartridges [silica (Si), aminopropyl‐bonded silica (NH2) and diol‐bonded silica (2OH)] at the same ratio of oil to sorbent mass were used to study the separation of PL from the extracted oil. The recovery of each standard PL was performed in a model oil system with the same amount of standard PL being added, and the repeatability of the SPE method was investigated. The isolation of PL by SPE diol cartridge and subsequent analysis by HPLC/ELSD have shown to be an accurate and reproducible analytical method for the determination of phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and lysophosphatidylcholine in PPF. This method provided a high yield and rapid separation of PL in PPF with less contamination from other lipid groups. 相似文献
3.
Chicken egg contains a high level of phospholipids (PL) in the yolk. Recovering yolk total lipids and extracting egg PL with efficiency are important to the availability and utilization of these health‐promoting lipid products. In this study, we prepared two structured dry egg yolk materials and used two common solvents to extract and concentrate the PL. We found that drum‐dried flake‐like yolk is an ideal starting material for lipid extraction. Anhydrous ethanol can extract almost all the neutral lipids and PL. PL with purity over 90% can be prepared by cold acetone precipitation from the total lipids. 相似文献
4.
Phospholipid hydroperoxides are detoxified by phospholipase A<Subscript>2</Subscript> and GSH peroxidase in rat gastric mucosa 总被引:1,自引:1,他引:0
The aim of this study was to determine the metabolic fate of phospholipid hydroperoxides (PLOOH) in rat gastric mucosa. Here
we report evidence concering the mechanism for PLOOH detoxification in gastric mucosa homogenate. Analysis by the TLC blot
technique showed that the gastric mucosa has the highest potential to eliminate 1-palmitoyl-2-linoleoyl-phosphatidylcholine
hydroperoxides (PL-PtdChoOOH) compared with the intestinal mucosa and liver. Major products detected after incubation with
gastric mucosa were the partially reduced linoleic acid hydroperoxides (LAOOH) and lysophosphatidylcholine, indicating the
involvement of phospholipase A2 (PLA2) in the elimination pathway. Using unilamellar vesicles, we demonstrated that gastric mucosal PLA2 does not distinguish between PLOOH and intact phospholipids. Although gastric mucosal PLA2 activity efficiently eliminated excess amounts of PLOOH, the complete reduction of LAOOH was dependent on the supply of exogenous
GSH. In a separate experiment, administration of egg yolk PtdChoOOH to rats for 6 d significantly elevated GSH peroxidase
(GPx) activity in the gastric mucosa. We concluded that excess amounts of PLOOH are efficiently eliminated through the hydrolysis
by PLA2, and the subsequent reduction of FA hydroperoxide by GPx is the critical step for complete detoxification of oxidized phospholipids
in the stomach. 相似文献
5.
Preparation of hydroperoxy and hydroxy derivatives of rat liver phosphatidylcholine and phosphatidylethanolamine 总被引:2,自引:2,他引:0
A convenient method for the preparation of hydroperoxy and hydroxy derivatives of phosphatidylcholine (PC) and phosphatidylethanolamine
(PE) is described. PC and PE obtained from rat liver were oxidized with singlet oxygen by using methylene blue as the photosensitizer,
and their hydroperoxides were isolated with the aid of reverse phase liquid chromatography. The hydroxy derivatives were obtained
by reducing the hydroperoxides with sodium borohydride. The results of gas chromatography mass spectrometry revealed that
hydroxy fatty acid components of the hydroxy derivatives were derived from isomeric hydroperoxides of oleic acid, linoleic
acid, arachidonic acid and docosahexanoic acid. Normal phase high performance liquid chromatography did not separate the hydroperoxy
and hydroxy derivatives from the respective unoxidized phospholipids, although unoxidized PC and PE were separated from each
other. However, the hydroperoxy and hydroxy derivatives could be distinguished from unoxidized phospholipid species on reversed
phase thin layer chromatography. 相似文献
6.
Chicken egg yolk is a concentrated source of phospholipids (PL). Extracting egg PL with high efficiency is vital to the availability and economics of this high-valued lipid product. In this study, two types of structured dry egg yolk materials, yolk flakes and pellets, were prepared. Two commonly used solvents, hexane and ethanol, were tested on the extraction of total yolk lipids including the PL. The PL fraction was obtained by the conventional cold acetone precipitation. The drum-dried yolk flakes were shown to be an ideal starting material for total lipid and PL extraction. Anhydrous ethanol can extract almost all the neutral lipids and PL with little change to the individual components of the native PL. A PL product with a purity of more than 90 % and a yield of 99 % can be prepared using this method. 相似文献
7.
Lisette Steenhorst-Slikkerveer Arjan Louter Hans-Gerd Janssen Christina Bauer-Plank 《Journal of the American Oil Chemists' Society》2000,77(8):837-845
Nonvolatile triacylglyceride (TAG) oxidation products play an important role in the oxidative degradation of lipids. They
serve as a reservoir of oxygen-containing species and hence can act as off-flavor precursors or as initiators for further
oxidation reactions. Possible nonvolatile lipid oxidation products are TAG with a hydroperoxy, hydroxy, epoxy, or oxo (ketone
or aldehyde) group or combination of these groups. The breakdown of TAG hydroperoxides yields nonvolatile glyceride species
with two intact fatty acid chains and one short chain mostly ending in an aldehyde or hydroxy group (2 1/2 glycerides). By
means of normal-phase high-performance liquid chromatography (HPLC) with mass spectrometric (MS) detection, non-volatile lipid
oxidation products can be separated according to polarity. This results in separation into classes of TAG oxidation products,
such as epoxy-TAG, oxo-TAG, hydroperoxy-TAG, hydroxy-TAG and 2 1/2 glycerides, which can be identified using selected ion
chromatograms. The retention times of TAG oxidation products on the normal-phase HPLC system and the signal intensity of the
MS detector are stable enough to enable quantitative analysis based on external calibration. The normal-phase HPLC-MS method
is very suitable for the characterization and quantitation of nonvolatile TAG oxidation products in oxidized TAG reference
compounds as well as in real oils or oil phases isolated from emulsions, spreads, or other fat-based food products. This method
can give detailed information for the study of lipid oxidation mechanisms.
Presented at the 15th Montreux Symposium on Liquid Chromatography/Mass Spectrometry, Montreux, Switzerland, November 9–10,
1998. 相似文献
8.
Isolation of Pure Phospholipid Fraction from Egg Yolk 总被引:1,自引:0,他引:1
Witold Gładkowski Anna Chojnacka Grzegorz Kiełbowicz Tadeusz Trziszka Czesław Wawrzeńczyk 《Journal of the American Oil Chemists' Society》2012,89(1):179-182
The phospholipid (PL) fraction from egg yolk was isolated and purified. In the procedure applied (method 2) the egg yolk was
extracted with ethanol, precipitated using acetone chilled to −20 °C and washed using acetone. The purity of the samples was
checked by HPLC analysis using a Charged Aerosol Detector (CAD). The results were compared with those obtained for the phospholipid
fraction isolated and purified by deoiling yolk before extraction and the precipitation of PL with acetone chilled to 4 °C
(method 1). The use of acetone chilled to −20 °C to precipitate and wash the phospholipids yielded the phospholipid fraction
with 100% purity (78.7 ± 0.2 of phosphatidylcholine and 21.3 ± 0.2 of phosphatidylethanolamine). When deoiling and the 4 °C
purification process was used (method 1) 0.4 ± 0.1% cholesterol and some traces of triacylglycerols remained in the PL fraction. 相似文献
9.
Hydroperoxy derivatives of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) can be separated from their respective
phospholipids by reverse-phase high performance liquid chromatography (HPLC). However, ultraviolet absorption due to conjugated
diene cannot detect the hydroperoxy group. In this work, an electrochemical (EC) detector was first applied to the analysis
of hydroperoxy phospholipids. Both the PC and PE hydroperoxides from rat liver were reduced quantitatively by the glassy carbon
electrode at −300 mV vs Ag/AgCl. Since neither the hydroxy derivatives nor unoxidized phospholipids showed any response, it
would seem this technique can be used to distinguish phospholipid hydroperoxides from their hydroxy derivatives. Thus, the
reverse phase HPLC-EC detection method is proposed for the specific analysis of hydroperoxy phospholipids in biological tissues. 相似文献
10.
Hui Wang Linxing Yao Show-Ling Lee Tong Wang 《Journal of the American Oil Chemists' Society》2017,94(2):309-314
Two alcohols, ethanol and butanol, with different water contents were evaluated for phospholipids (PL) sequential extraction from drum dried egg yolk flakes. It showed that butanol was more effective in extracting total yolk lipids compared to ethanol, but the PL in the extract had the same concentration as in the original yolk total lipid. The use of aqueous ethanol of 95 and 75% resulted in lipid extracts with higher PL concentration during the initial stages of the sequential extraction. When ethanol was further diluted to a concentration of 55%, the solvent lost its PL extraction ability, and the total lipid recovery also decreased dramatically. When both the PL purity and recovery were considered, 75% ethanol was the most effective aqueous alcohol for PL extraction and enrichment from the yolk flakes. In the first stage of extraction using such a solvent, 67% of the total PL in the original yolk was recovered in a lipid fraction with a PL purity of 75%. This study identified the optimal ethanol concentration for PL extraction from dried egg yolk. With this information, the best solid:solvent ratio can be designed to extract and enrich the polar lipids from lipid-bearing materials with known moisture content using a renewable or “green” solvent, ethanol. 相似文献
11.
Characterization of purified phospholipids from krill (Euphausia superba) residues deoiled by supercritical carbon dioxide 总被引:1,自引:0,他引:1
Purification of phospholipids (PL) from the Antarctic krill (Euphausia superba) using a two-step extraction process has been investigated. Using supercritical carbon dioxide (SC-CO2) extraction with optimal extractions conditions of 45 °C, 25MPa, and CO2 flow rate of 22 g/min, most of the neutral lipids were extracted. PC, PE and PI were then extracted in a second step conducted with modified existing method using ethanol, hexane and acetone as solvents. The major PL of krill residues was quantified by high performance liquid chromatography (HPLC-ELSD). The fatty acid compositions of total PL, PC, PE and PI were analyzed by gas chromatography (GC). A significant amount of polyunsaturated fatty acids (PUFA) was present in both total and PLs fractions. The purified PLs were characterized by their acid value, peroxide value, and the oxidative stability. The purity of PL ranged between 93 and 97% and was evaluated by spectrophotometry. 相似文献
12.
A method is described for the purification of a number of phospholipids by preparative high performance liquid chromatography
(HPLC). Purification of digalactosyl-diglyceride from spinach and egg phosphatidylcholine, 1,2-dioleoyl-sn-glycero-3-phosphocholine and 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine from its reaction mixture have been resolved. The lipid separation is performed on a polygosil
column and the individual compounds are monitored directly by refractive index detection. Chloroform/methanol mixtures are
used as eluent systems, providing a wide polarity range to separate the classes of lipids. The developed equipment can be
used for columns between 10 and 50 cm long and 4 and 50 mm inner diameter. The flow rate could be varied between 1 and 100
ml/min and applied pressures between 10 and 450 bars. 相似文献
13.
An improved method for the analysis of phospholipids by normal-phase HPLC is described. Addition of methanol and acetonitrile
to a gradient based on 2-propanol/hexane/water promoted a rapid separation of major classes of bovine surfactant phospholipids
(PL) by using a conventional silica column. The use of an ELSD permitted an accurate analysis of a mixture of PL. Calibration
curves were linear within the range of 5–40 μg with detection limits below 1 μg for PE and PC, and CV ranged from 0.6 to 9.6%.
PL present in surfactant homogenates were separated by a solid-phase extraction (SPE) procedure before HPLC analysis. This
methodology gave a recovery of 95% and combined SPE-HPLC and quantification of biological PL within a 30-min run. The use
of ELSD detection of the eluted compounds was precise, linear, and sensitive. 相似文献
14.
Limitations of the method using peroxidase activity of hemoglobin for detecting lipid hydroperoxides
The method using peroxidase activity of hemoglobin (Hb) for the determination of lipid peroxides was examined by using pure
methyl linoleate hydroperoxides, trilinoleoylglycerol hydroperoxides and egg yolk phosphatidylcholine hydroperoxides as substrates
and tetramethyl benzidine as electron donor for the peroxidase reaction of Hb. The reactivities of these substrates were quite
varied. Furthermore, some electron donors were tested for peroxidase activity of Hb, but none showed a complete reduction
of methyl linoleate hydroperoxides. From these results, it seems the Hb method needs to be carefully applied to biological
materials that contain mixtures of different types of lipid classes. 相似文献
15.
Normal-phase high-performance liquid chromatography separations of phospholipids (PL) depend heavily on the variation in mobile
phases. Incorporation of pure tetrahydrofuran to a mobile phase of chloroform, methanol, and ammonium hydroxide improved the
separation of polar phospholipids. However, impurities were often found to be present in tetrahydrofuran that caused severe
peak interferences with PL analytes. The use of a common chromatographic solventtert.-butyl methyl ether, in lieu of tetrahydrofuran in mobile phases, eliminated problems associated with solvent contamination
and yielded reproducible results. The modified method has been applied for the quantitative analysis of phospholipids in crude
soybean oils. 相似文献
16.
The molecular species in mixtures of phospholipid hydroperoxides are difficult to separate and identify by typical chromatographic
and mass spectrometric techniques. As reported by Havrilla and coworkers, silver ion coordination ionspray mass spectrometry
(CIS-MS) has proven to be a powerful technique for the identification of mixtures of hydroperoxides. This ionization technique,
which involves the formation of Ag+ adducts of the hydroperoxides, provides valuable, unambiguous structural information about the hydroperoxides. Herein, we
report a method for the analysis and identification of phospholipid hydroperoxides using CIS-MS. We also report an improved
method for the separation of phospholipid hydroperoxides by reversed-phase high-performance liquid chromatography (RP-HPLC),
which, for the first time, separates some of the hydroperoxide isomers. CIS-MS can be coupled with this RP-HPLC method by
the addition of AgBF4 to the mobile phase or to the HPLC effluent postcolumn, thus allowing powerful HPLC-MS techniques to be used to identify
complex mixtures of phospholipid hydroperoxides. 相似文献
17.
The effect of N-ethyl-maleimide (NEM) on Δ5-and Δ6-desaturase activities and the incorporation of substrates and products into different
microsomal lipid classes and phospholipid (PL) subclasses were studied in human fetal liver microsomes, obtained after legally
approved therapeutic abortion. Desaturase activities were measured by a radiochemical method using reversed-phase high-performance
liquid chromatography (HPLC). After nonphospholipid (NPL) and PL separation on silica cartridges, the radioactivity in different
lipids of the NPL group was assessed by two-dimensional thin-layer chromatography, and their fatty acid (FA) composition by
gas-liquid chromatography. The PL subclasses were separated, and the distribution of radioactivity between products and substrates
was determined in PL subclasses. NEM inhibited the Δ5- and Δ6-desaturase activities in the n−6 series of FA but not the Δ6-desaturase
activity in the n−3 series, which suggests the existence of two distinct Δ6-desaturases, one for the n−6 series and another
for the n−3 series. Whether NEM was present or absent, most of the radioactivity was recovered in the free FA form (about
80%). The desaturation products, obtained in the presence or absence of NEM, were preferentially incorporated into PL, suggesting
a channeling of the newly synthesized FA toward microsomal PL. The comparison of the distribution of substrates and products
incorporated into the different PL classes showed that most of the labeled FA were incorporated into phosphatidylcholine and
to a lesser degree into phosphatidylethanolamine. 相似文献
18.
Mayonnaise samples were prepared using DAG oil as the oil phase; the properties and stability were compared with mayonnaise
samples prepared from TAG oil. Normal (nontreated) egg yolk and phospholipase A2 (PLA2)-treated egg yolk were used as emulsifiers. The DAG oil mayonnaise prepared with nontreated egg yolk (DAG-M) was unstable,
with cracks forming within 4 wk at 40°C. This type of fracture was not observed for TAG oil mayonnaise prepared with nontreated
egg yolk (TAG-M). 31P NMR and quantitative analyses of phospholipids suggested that the phospholipids of egg yolk lipoprotein were dissolved in
DAG-M oil droplets, which might result in the coalescence and fracture of the DAG-M. Phospholipids were not dissolved in TAG-M
oil droplets. No crack formation was observed for DAG oil mayonnaise prepared with PLA2-treated egg yolk (DAG-PLM) after storage
for more than 4 wk at 40°C. 31P NMR spectroscopy and quantitative analyses of phospholipids indicated that the dissolution of phospholipid molecules into
the oil droplets was almost prevented in DAG-PLM. The stability of DAG-PLM is improved probably because the PLA2 treatment
changes the molecular polarity of egg yolk phospholipids and prevents them from dissolution into the DAG oil droplets from
oil/water interface. 相似文献
19.
Sahar Navidghasemizad Alexandra Acero-Lopez Jonathan Curtis Feral Temelli Jianping Wu 《Journal of the American Oil Chemists' Society》2014,91(11):1857-1866
The objective of this study was to destabilize the protein–lipid complex in egg yolk precipitate obtained after the removal of soluble proteins, referred to as the pellet, through enzymatic treatment for further phospholipids extraction. A combination of proteolytic and lipolytic enzymes was applied to release the lipids from the pellet or weaken the pellet emulsion. Emulsions prepared using Protease P/Lipase AY30, Protease II/Lipase AY30 and Protease M/Lipase AY30 treated pellets had larger oil droplets (78, 65, 56 µm) and higher coalescence rates (51, 41, 35 %) than those of Protex 51FP, pellet, Protex 7L and Protease A with oil droplet size of 20, 18, 15 and 13 µm and coalescence rates of 31, 8, 7.5 and 8 %, respectively. Cream and liquid subnatant fractions obtained after further centrifugation of hydrolysates were subjected to lipid analyses. Over 90 % of phosphatidylcholine (PC) present in the pellet and 80 % of that in the original egg yolk were recovered in the cream from Protease P/Lipase AY30 treatment, while the recovery of PC from the egg yolk was significantly lower in creams from Protex 7L or Protease 51FP treatments (12 and 10 %, respectively). Pellets treated with Protease M, Protex 7L or Protex 51FP in combination with Lipase AY30 led to a significant loss of PC due to the conversion of PC to lysophosphatidylcholine or its degradation. Cream fractions obtained from the study represented a better material for the recovery of PL than intact egg yolk using environmentally-friendly techniques such as supercritical carbon dioxide (SC-CO2) extraction. 相似文献
20.
Two unsymmetric polyunsaturated lecithins were allowed to air oxidize and the primary products of autoxidation were isolated
and characterized. 1-Palmitic-2-linoleic-phosphatidylcholine undergoes significant oxidation after 16 hr at room temperature
under air. A new phospholipid product may be isolated by reverse phase high pressure liquid chromatography (HPLC) and this
HPLC fraction is shown to be made up of lipid hydroperoxides formed by free radical oxidation of the homoconjugated diene
of the linoleate component of the lecithin. 1-Stearic-2-arachidonic-phosphatidylcholine undergoes a similar oxidation with
the arachidonate polyunsaturated functionality being oxidized. The structure of the oxidation products was established by
reduction of hydroperoxide with triphenylphosphine, snake venom hydrolysis of the C-2 ester, and HPLC analysis of the resulting
hydroxy fatty acids or their methyl esters. 相似文献