Separation and characterization of peanut phospholipid molecular species using high-performance liquid chromatography and fast atom bombardment mass spectrometry

Fate of phospholipids during aqueous extraction processing of peanut and effect of demulsification treatments on oil-phosphorus-content

PC (phosphatidylcholine), PE (phosphatidylethanolamine), PI (phosphatidylinositol), and PA (phosphatidic acid) in 9 peanut matrices obtained during the AEP (aqueous extraction processing) of peanut were quantified employing HPLC-ELSD analysis in this study. Phosphorus contents of crude oils obtained from different demulsification treatments were also investigated. Decantation had a larger effect than grinding in terms of phospholipids loss due to alkaline-hydrolysis, indicating this processing step was vital for the manipulation of phospholipids levels remained in oil. Over 80% of initial phospholipids were lost during AEP and only 19.8% of initial phospholipids ended up in cream, skim and sediment phase. 52.55% of the remained phospholipids trapped in cream phase. Just 22.16-32.61 mg/kg phosphorus content could be detected in crude oils, which indicated the separation of phospholipids from the cream phase into aqueous medium. Degumming was not essential in AEP of peanut and the waste generated after demulsification could be a source of phospholipids.

Natural phospholipids: Occurrence, biosynthesis, separation, identification, and beneficial health aspects

During the last years, phospholipids (PLs) have attracted great attention because of their crucial roles in providing nutritional values, technological and medical applications. There are considerable proofs that PLs have unique nutritional benefits on human health, such as reducing cholesterol absorption, improving liver functions, and decreasing the risk of cardiovascular diseases. PLs are the main structural lipid components of cell and organelle membranes in all living organisms, and therefore, they occur in all organisms and the derived food products. PLs are distinguished by the presence of a hydrophilic head and a hydrophobic tail, consequently they possess amphiphilic features. Due to their unique characteristics, the extraction, separation, and identification of PLs are critical issues to be concerned. This review is focused on the content of PLs classes in several sources (including milk, vegetable oils, egg yolk, and mitochondria). As well, it highlights PLs biosynthesis, and the methodologies applied for PLs extraction and separation, such as solvent extraction and solid-phase extraction. In addition, the determination and quantification of PLs classes by using thin layer chromatography, high-performance liquid chromatography coupled with different detectors, and nuclear magnetic resonance spectroscopy techniques.

Comparison and characterization of soybean and sunflower lecithins used for chocolate production by high-performance thin-layer chromatography with fluorescence detection and electrospray mass spectrometry

The scarce availability of nongenetically modified soybeans on the world market represents a growing problem for food manufacturers. Hence, in this study the effects of substituting soybean with sunflower lecithin were investigated with regard to chocolate production. The glycerophospholipid pattern of the different lecithin samples was investigated by high-performance thin-layer chromatography fluorescence detection (HPTLC-FLD) and by HPTLC-positive ion electrospray ionization mass spectrometry (ESI(+)-MS) via the TLC-MS Interface and by scanning HPTLC-matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS). Especially, the contents of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were of interest due to the influencing effects of these two glycerophospholipids on the rheological parameters of chocolate production. The lecithin substitution led to only slight differences in the rheological parameters of milk and dark chocolate. Limits of detection (LODs) and limits of quantification (LOQs) of seven glycerophospholipids were studied for three detection modes. Mean LODs ranged from 8 to 40 mg/kg for HPTLC-FLD and, using a single-quadrupole MS, from 10 to 280 mg/kg for HPTLC-ESI(+)-MS as well as from 15 to 310 mg/kg for HPTLC-FLD-ESI(+)-MS recorded after derivatization with the primuline reagent.

Identification of glycerophospholipids in rapeseed, olive, almond, and sunflower oils by LC–MS and LC–MS–MS

HPLC employing a thermostatted Lichrospher 100 diol column was used to separate mixtures of glycerophospholipids of rapeseed, olive, almond, and sunflower oils. Elution was performed with a binary gradient of two mixed solvents A: hexane – isopropanol – acetic acid – triethylamine (82:17:1.0:0.08 v/v/v/v) and B: isopropanol – water – acetic acid – triethylamine (85:14:1.0:0.08 v/v/v/v). The LC effluent was directly introduced into the mass spectrometer through an electrospray capillary. Information about the fatty acid composition of each glycerophos pho lipid class was given by tandem mass spectrometry (MS–MS). These techniques permitted a rapid separation and identification of complex mixtures of glycerophospholipids. The relative abundance of each lipid class in each oil was also determined. The resulting glycerophospholipid signature may provide an efficient means of identifying oil origin and possible adulteration.Key words: glycerophospholipids, vegetable oils, tandem mass spectrometry, LC–MS.

Phospholipids from Bombycis corpus and their neurotrophic effects

Three phospholipids (4-6) and three aromatic amines (1-3) were obtained from the methanol extract of Bombycis corpus. Based on spectral data, their structures have been elucidated as nicotiamide (1), cytidine (2), adenine (3), 1-O-(9Z-octadecenoyl)-2-O-(8Z,11Z-octadecadienoyl) sn-glycero-3-phosphorylcholine (4), 1,2-di-O-hexadecanoyl-sn-glycero-3-phosphorylcholine (5) and 1,2-di-O-9Z-octadecenoyl-sn-glycero-3-phosphorylcholine (6). We examined the effects of compounds on synthesis of NGF in cultured astrocytes. By RT-PCR analysis, expresison of NGF mRNA in astrocytes cultured in serum-starvation increased after the addition of phospholipid (10 microM). The NGF content in the culture medium was significantly increased by compound 5, compared with the control value. These results suggest that three phospholipid compounds isolated from the methanol extract of Bombycis corpus may exert neurotrophic effects by stimulation of NGF synthesis in astrocytes.

Analysis of phospholipid molecular species by liquid chromatography--atmospheric pressure chemical ionisation mass spectrometry of diacylglycerol nicotinates

A method using liquid chromatography - atmospheric pressure chemical ionisation mass spectrometry was evaluated for determining the molecular species composition of phospholipids (phosphatidylcholines from soybean, egg yolk and bovine liver) after conversion to diacylglycerol nicotinate derivatives. The structures could be deduced from pseudo-molecular ions ([MH-123](+)) and three pairs of monoacyl containing fragment ions. All molecular species in mixed peaks were readily identified and many minor components, earlier not encountered in the samples under investigation, were identified. Acyl chain regioisomers were readily distinguished by the ratio of the [MH-RCHCO](+) ions. Molecular species differing only in the position of the double bonds in one polyunsaturated acyl chain were separated on the basis of retention times. A half quantitative estimation of the molecular species composition of complex samples was achieved by a combination of UV detection and, for mixed peaks, the areas of [MH-123](+) ions.

In situ derivatisation using pressurized liquid extraction to determine phenols, sterols and carboxylic acids in environmental samples and microbial biomasses

Pressurized liquid extraction was combined with in-situ derivatisation to extract polar analytes such as phenols (including chlorophenols) sterols and carboxylic acids from environmental and microbial samples. This one-step protocol uses acetic anhydride as an acetylation agent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA) as an silylation agent, and boron trifluoride-methanol, phenyltrimethyl ammoniumhydroxide and trimethyl sulfoniumhydroxide as methylation agents. It results in faster extraction rates and better or comparable extraction efficiencies when compared to classical approaches. The addition of a silylation agent also facilitates the extraction kinetics of analytes not accessible to silylation (e.g. polycyclic aromatic hydrocarbons or alkylbenzenes). This may be attributed to a dissociative action of the agent to weaken analyte-matrix interactions.