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Glucuronic acid containing diacylglycerols (3-(O-α-d-glucuronopyranosyl)-1,2-diacyl-sn-glycerols, GlcA-DAG) are glycolipids of plant membranes especially formed under phosphate-depletion conditions. An analytical approach for the structural characterization of GlcA-DAG in red ripe tomato (Solanum lycopersicum L.) extracts, based on reversed-phase liquid chromatography (RPLC) coupled with electrospray ionization (ESI) and tandem mass spectrometry (MS/MS) using a linear ion trap, is described in this paper. At least 14 GlcA-DAG (R1/R2) species, including four regioisomers, containing three predominant fatty acyl chains C16:0, C18:2, and C18:3, were identified for the first time. Moreover, 29 GlcA-DAG acylated on the glucuronosyl ring (acyl-R3 GlcA-DAG) were discovered, alongside 15 acylated lyso-forms, i.e., acylated 3-(O-α-d-glucuronosyl)monoacylglycerols, abbreviated as acyl-R3 GlcA-MAG (R1/0) or (0/R2). Although many of these acylated lyso-forms were isomeric with GlcA-DAG (i.e., acyl chains with equivalent sum composition), they were successfully separated by reversed-phase liquid chromatography (RPLC) using a solid-core C18 column packed with 2.6 μm particle size. Tandem MS (and eventually MS3) data obtained from sodium adducts ([M + Na]+) and deprotonated molecules ([M - H]-) were fundamental to detect diagnostic product ions related to the glucuronosyl ring and then determine the identity of all investigated glycolipids, especially to recognize the acyl chain linked to the ring. A classification of GlcA-MAG, GlcA-DAG, and acylated GlcA-DAG and GlcA-MAG was generated by an in house-built database. The discovery of acylated derivatives emphasized the already surprising heterogeneity of glucuronic acid-containing mono- and diacylglycerols in tomato plants, stimulating interesting questions on the role played by these glycolipids.

In the past decade, hydrophilic interaction liquid chromatography (HILIC) has emerged as an efficient alternative to reversed-phase chromatography (RPC) for the analysis of phospholipid (PL) mixtures based on mass spectrometric detection. Since the separation of PL by HILIC is chiefly based on their headgroup, the mass spectrum of each class can be obtained by spectral averaging under the corresponding HILIC band. Using experimental m/z values resulting from high mass resolution/accuracy instruments, the sum compositions of PL in a specific class can be thus inferred but partial overlapping may occur between signals related to the M + 0 isotopologue of one species and the M + 2/M + 4 isotopologues of species having one/two more C═C bonds in their chemical structures. Here, an automated workflow, named LIPIC (lipid isotopic pattern interference correction), is proposed to account for such interferences. Starting from the experimentally verified assumption that peaks in isotope patterns are Gaussian, LIPIC predicts, as a function of m/z ratio, signal intensities due to M + 2 and M + 4 isotopologues of species with one or two more C = C bonds than the target one and calculates the corrected intensity for the M + 0 isotopologue of the latter. Thanks to an iterative procedure, the suggested algorithm compensates also for slight shifts occurring between experimental and theoretical m/z ratios related to isotopologue peaks. Examples of applications to simulated and experimental mass spectra of two PL classes, i.e., phosphatidylcholines (PC) and cardiolipins (CL), emphasize the increased extent of correction at the increase of molecular masses of involved species.

Water-soluble diacyl arsenosugar phospholipids (As-PL) are natural products widespread in marine animals and algae, including the brown alga

The study of negative effects potentially exerted by the exposure to oxygen and/or light and, thus, also by the type of container on the quality of extra virgin olive oil (EVOO) during its prolonged storage requires an appropriate choice of analytical methods and components to be monitored. Here, reverse-phase liquid chromatography coupled to high-resolution/accuracy Fourier transform mass spectrometry with electrospray ionization was exploited to study oxidative/hydrolytic degradation processes occurring on the important bioactive components of EVOO known as secoiridoids, i.e., oleuropein and ligstroside aglycones, oleacin, and oleocanthal, during storage up to 6 months under controlled conditions. Specifically, isomeric oxidative byproducts resulting from the transformation of a carbonylic group of the original secoiridoids into a carboxylic group and compounds resulting from hydrolysis of the ester linkage of secoiridoids, i.e., elenolic and decarboxymethyl elenolic acids and tyrosol and 3-hydroxytyrosol, were monitored, along with their precursors. Data obtained from EVOO storage at room temperature in glass bottles with/without exposure to light and/or oxygen indicated that, although it was more relevant if a periodical exposure to oxygen was performed, a non-negligible oxidative degradation occurred on secoiridoids also when nitrogen was used to saturate the container headspace. In a parallel experiment, the effects of storage of the same EVOO (250 mL) for up to 6 months in containers manufactured with different materials/shapes were considered. In particular, a square dark glass bottle, a stainless-steel can, and a ceramic jar, typically used for EVOO commercialization, and a clear polyethylene terephthalate bottle, purposely chosen to prompt secoiridoid degradation through exposure to light and oxygen, were compared. Dark glass was found to provide the best combined protection of major secoiridoids from oxidative and hydrolytic degradation, yet the lowest levels of oxidized byproducts were observed when the stainless-steel can was used.

1,2-diacyl-sn-glycero-3-phospho-N-acyl-ethanolamines (NAPE) are low abundance phospholipids but important constituents of intracellular membranes of plant tissues, responsible to generate bioactive...

A novel strategy based on in situ dual-enzyme digestion of paint layer proteinaceous binders is introduced for faster and more confident identification, resulting in a bottom-up proteomics approach by MALDI-TOF mass spectrometry (MS). In situ sampling/extraction of proteinaceous binders using small pieces of a hydrophilic gel, previously loaded with trypsin and chymotrypsin proteolytic enzymes, was successfully exploited. Along with minimal invasiveness, the synergy of both enzymes was very useful to increase the number of annotated peptide peaks with their corresponding amino acid sequence by database search and subsequent MALDI-TOF/TOF analysis. The protocol was initially aimed at enhancing the identification of egg-based binders and then validated on fresh and aged model pictorial layers; an increased protein coverage was significantly attained regardless of the used painting binders. Optical microscope images and spectrophotocolorimetry analysis evidenced that the painting layers were not damaged or altered because of contact/sampling without leaving hydrogel residues. The proposed protocol was successfully applied on a painted altarpiece "Assumption of the Virgin" dated to the XVI century and on an angel statue of the Nativity crib dated to the XII century, both from Altamura's Cathedral (Apulia, Italy). The occurrence of various protein binders of animal origin was easily and reliably ascertained.

Spirulina microalga (Arthrospira platensis) is an interesting phototrophic organism because of its high content of nutrients including proteins, lipids, essential amino acids, antioxidants, vitamins, polysaccharides, and minerals. Hydrophilic interaction liquid chromatography (HILIC) coupled to linear ion trap (LIT) and Orbitrap Fourier transform mass spectrometry (FTMS) via ESI was employed for the separation and characterization of lipid species in A. platensis. Inositolphosphoceramides (IPC) are minor but important constituents of spirulina; their investigation was accomplished by HILIC-ESI-MS including collision-induced dissociation (MS2 , MS3 ) of deprotonated molecules in the LIT analyzer and a schematic fragmentation pattern is described. All four commercial spirulina samples revealed the occurrence of the same IPC species at m/z 796.6 (d18:0/16:0;1), 810.6 (d18:0/17:0;1), 824.6 (d18:0/18:0;1), and 826.6 (d18:0/17:0;2) but in diverse relative abundance. This study sets the stage for future investigations on IPC in other algae and microalgae.

The chemical identity of arsenosugar phospholipids (As-PL) as mono- (i.e., lyso, L-As-PL) and diacyl-arsenosugar PL in four edible and common marine alga samples, such as nori (Porphyra spp.), waka...

Microgreens are a special type of vegetal product, born as a culinary novelty (traditionally used to garnish gourmet dishes) and then progressively studied for their potentially high content in nutraceuticals, like polyphenolic compounds, carotenoids, and glucosinolates, also in the perspective of implementing their cultivation in space stations/colonies. Among further potential nutraceuticals of microgreens, lipids have received very limited attention so far. Here, glycerophospholipids contained in microgreens of typical oleaginous plants, namely, soybean, chia, flax, sunflower, and rapeseed, were studied using hydrophilic interaction liquid chromatography (HILIC), coupled to high-resolution Fourier transform mass spectrometry (FTMS) or low-resolution collisionally induced dissociation tandem mass spectrometry (CID-MS

Surfactants are surface-active agents widely used in numerous applications in our daily lives as personal care products, domestic, and industrial detergents. To determine complex mixtures of surfactants and their degradation products, unselective and rather insensitive methods, based on colorimetric and complexometric analyses are no longer employable. Analytical methodologies able to determine low concentration levels of surfactants and closely related compounds in complex matrices are required. The recent introduction of robust, sensitive, and selective mass spectrometry (MS) techniques has led to the rapid expansion of the surfactant research field including complex mixtures of isomers, oligomers, and homologues of surfactants as well as their chemically and biodegradation products at trace levels. In this review, emphasis is given to the state-of-the-art MS-based analysis of surfactants and their degradation products with an overview of the current research landscape from traditional methods involving hyphenate techniques (gas chromatography-MS and liquid chromatography-MS) to the most innovative approaches, based on high-resolution MS. Finally, we outline a detailed explanation on the utilization of MS for mechanistic purposes, such as the study of micelle formation in different solvents.

The uncontrolled activation of endogenous enzymes may introduce both qualitative and quantitative artefacts when lipids are extracted from vegetal matrices. In the present study, a method based on hydrophilic interaction liquid chromatography coupled either to high-resolution/accuracy Fourier-transform mass spectrometry (HILIC-ESI-FTMS) or to linear ion trap multiple stage mass spectrometry (HILIC-ESI-MSn , with n = 2 and 3) with electrospray ionization was developed to unveil one of those artefacts. Specifically, the artificial generation of methyl esters of phosphatidic acids (MPA), catalysed by endogenous phospholipase D (PLD) during lipid extraction from five oleaginous microgreen crops (chia, soy, flax, sunflower and rapeseed), was studied. Phosphatidylcholines (PC) and phosphatidylglycerols (PG) were found to be the most relevant precursors of MPA among glycerophospholipids (GPLs), being involved in a transphosphatidylation process catalysed by PLD and having methanol as a coreactant. The combination of MS2 and MS3 measurements enabled the unambiguous recognition of MPA from their fragmentation pathways, leading to distinguish them from isobaric PA including a further CH2 group on their side chains. PLD was also found to catalyse the hydrolysis of PC and PG to phosphatidic acids (PAs). The described transformations were confirmed by the remarkable decrease of MPA abundance observed when isopropanol, known to inhibit PLD, was tentatively adopted instead of water during the homogenization of microgreens. The unequivocal identification of MPA might be exploited to assess if GPL alterations are actually triggered by endogenous PLD during lipid extractions from specific vegetal tissues.

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.

RATIONALE Several bioactive compounds, including phenolic acids and secoiridoids, are transferred from olive drupes to olive oil during the first stage of production. Here, the characterization of these low molecular weight (LMW) compounds in olive oil and in closely related processing materials, like olive leaves (OL) and olive mill wastewaters (OMW), was faced up, for the first time, by matrix-assisted laser desorption/ionization (MALDI) time-of-flight mass spectrometry (TOF MS). METHODS A novel binary matrix composed of 1,8-bis(tetramethylguanidino)naphthalene (TMGN) and 9-aminoacridine (9AA) (1:1 molar ratio), displaying excellent ionization properties at low levels of laser energy, was employed in reflectron negative ion mode by a MALDI TOF/TOF system equipped with a neodymium-doped yttrium lithium fluoride (Nd:YLF) laser (345 nm). MS/MS experiments were performed by using ambient air as the collision gas. RESULTS Four major secoiridoids typically present in olive oil, i.e., the aglycones of oleuropein and ligstroside, and oleacein and olecanthal at m/z 377.1, 361.1, 319.1 and 303.1, respectively, were detected in virgin olive oil (VOO) extracts, along with some of their chemical/enzymatic hydrolysis by-products, such as elenolic (m/z 241.1), decarboxymethyl-elenolic acids (m/z 183.1) and hydroxytyrosol (m/z 153.1). Besides oleuropein aglycone and oleacein, hydroxylated derivatives of decarboxymethyl-elenolic acid and hydroxytyrosol were evidenced in OMW. CONCLUSIONS While oleuropein was confirmed in OL extracts, several interesting phenolic compounds, including hydroxytyrosol, were recognized in OMW. The proposed approach based on the use of a novel binary matrix for MALDI MS/MS analyses of LMW bioactive compounds can be considered a promising analytical tool for a rapid screening of the phenolic fraction in olive oils and related processing wastes.

The reactivity of the sulfur-containing nucleoside 4-thio-(2 '-deoxy)-thymidine usually abbreviated as 4-thio-thymidine, (S-4-TdR) under Fenton conditions, ie, in the presence of H2O2 and catalytic amounts of Fe(II), was investigated by UV-vis spectroscopy and electrospray ionization single and tandem mass spectrometry (ESI-MS and MS/MS). S-4-TdR hydroxylated on the S atom was found to be a key reaction intermediate, ultimately leading to (2 '-deoxy)-thymidine usually abbreviated as thymidine, (TdR) as the main reaction product. This finding was in accordance with the outcome of the reaction between S-4-TdR and H2O2, previously investigated in our laboratory. On the other hand, the additional presence of center dot OH radicals, induced by the Fe(II)/H2O2 combination, led to the increased generation of another interesting S-4-TdR product, already observed after its reaction with H2O2 alone, ie, the covalent dimer including a S-S bridge between two S-4-TdR molecules. More importantly, multihydroxylated derivatives of S-4-TdR and TdR were detected as peculiar products obtained under Fenton conditions. Among them, a product bearing an OH group both on the methyl group linked to the thymine ring and on the C5 atom of the ring was found to prevail. The results obtained during this study, integrated by those found previously in our laboratory, indicate 4-thiothymidine as a promising molecular probe for the recognition, through a careful characterization of its reaction products, of the prevailing species among reactive oxygen species (ROS) corresponding to singlet-state oxygen, hydrogen peroxide, and hydroxylic radical.

Several mobile phase additives (i.e., organic acids and their ammonium salts) were used to modulate the chromatographic retention of cyanocobalamin and its cis-diaminemonochloroplatinum(II) conjugate, depending on the specific nature of the stationary phase. Regardless of the mobile phase additive, the positively charged cyanocobalamin-cis-diaminemonochloroplatinum(II) conjugate was systematically less retained than cyanocobalamin on a conventional octadecyl-silica column. In contrast, the amide-embedded C18 column exhibited a progressive increase in the conjugate retention time upon changing the mobile phase additive from organic (acetic, formic and trifluoroacetic) acids to ammonium salts, ultimately leading to an inversion of the elution order. This change of retention was interpreted by invoking the interplay between hydrophobic interactions, hydrogen bonding between the conjugate and the polar amide groups and the ion-pairing ability of the lyophilic counterions, whereby the acetate anion was found to be the most suitable to control the solute retention.

Croconaine dyes are appealing molecules synthesized via the condensation of croconic acid and reactive electron-donating aromatic or heterocyclic systems. Here, matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) investigation of indolenine-based croconaines is presented for the first time. Archetype proton-transfer matrices, such as 2,5-dihydroxybenzoic acid (DHB) and α-cyano-4-hydroxycinnamic acid (CHCA), 9-aminoacridine (9AA) as the protonating/deprotonating matrix, and electron-transfer (ET) secondary-reaction matrices, such as 1,5-diaminonapthalene (DAN) and trans-2-[3-(4-t-butyl-phenyl)-2-methyl-2-propenylidene]malononitrile (DCTB), were investigated. DHB, CHCA, and 9AA generate a mix of odd-electron molecular ions and protonated, sodiated, and potassiated adducts. Among the ET matrices, DAN was found to be capable of directing the ionization process toward the exclusive formation of odd-electron molecular ions M+• without fragmentation. MALDI tandem MS provides useful structural characterization of croconaine dyes, thus making identification very straightforward for all investigated compounds. Interestingly the fragmentation of bromo-containing croconaines revealed, for the first time, the gas-phase formation of a bromime cation [Br]+.

The contribution of dysregulation of lipid signaling and metabolism to neurodegenerative diseases including Alzheimer’s and Parkinson’s is the focus of this special issue. Here, the matter of three reviews and one research article is summarized.

In the last two decades, phenolic compounds occurring in olive oils known as secoiridoids have attracted a great interest for their bioactivity. Four major olive oil secoiridoids, i.e., oleuropein and ligstroside aglycones, oleacin and oleocanthal, were previously characterized in our laboratory using reversed-phase liquid chromatography with electrospray ionization-Fourier transform-mass spectrometry (RPLC-ESI-FTMS). The same analytical approach, followed by multivariate statistical analysis (i.e., Principal Component Analysis), was applied here to a set of 60 Italian extra-virgin olive oils (EVOO). The aim was to assess the secoiridoid contents as a function of olive cultivars, place of cultivation (i.e., different Italian regions) and olive oil processing, in particular two- vs. three-phase horizontal centrifugation. As expected, higher secoiridoid contents were generally found in olive oils produced by two-phase horizontal centrifugation. Moreover, some region/cultivar-related trends were evidenced, as oleuropein and ligstroside aglycones prevailed in olive oils produced in Apulia (Southern Italy), whereas the contents of oleacin and oleocanthal were relatively higher in EVOO produced in Central Italy (Tuscany, Lazio and Umbria). A lower content of all the four secoiridoids was generally found in EVOO produced in Sicily (Southern Italy) due to the intrinsic low abundance of these bioactive compounds in cultivars typical of that region.

Operating micro-invasive sampling when dealing with the chemical investigation of precious historical works of art is, without doubts, mandatory. Recently, scientific research in the field of Cultural Heritage has been often devoted to the development of innovative strategies for quasi non-invasive sampling on works of art to extract, for example, proteins and/or lipids composing the pictorial binders gaining extensive awareness about the materials employed by the artist. In this work, we propose a novel minimally invasive method for the sampling and characterization of protein-based painting binders. We apply a hydrophilic gel, previously functionalized with trypsin and chymotrypsin, on the artwork surface to perform an in-situ digestion of proteinaceous binders. Peptides are identified by means of a proteomic bottom-up approach combined with a high resolution/accuracy mass spectrometry technique. A wooden polychrome statue belonging to the XV century was chosen as a sample to assess the proposed protocol on a historical painting layer, as illustrated herein.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is largely recognized as an important tool in the analysis of many biomolecules such as proteins and peptides. The MS analysis of digested peptides to identify a protein or some of its modifications is a key step in proteomics. MALDI-MS is well suited for the peptide mass fingerprinting (PMF) technique, as well as selected fragmentation of various precursors using collisional-induced dissociation (CID) or post-source decay (PSD).In the last few years, MALDI-MS has played a significant role in food chemistry, especially in the detection of food adulterations, characterization of food allergens, and investigation of protein structural modifications induced by various industrial processes that could be an issue in terms of food quality and safety.Here, we present simple extraction protocols of allergenic proteins in food commodities such as milk, egg, hazelnut , and lupin seeds. Classic bottom-up approaches based on Sodium Dodecyl Sulphate (SDS) gel electrophoresis separation followed by in-gel digestion or direct in-solution digestion of whole samples are described. MALDI-MS and MS /MS analyses are discussed along with a comparison of data obtained by using the most widespread matrices for proteomic studies, namely, α-cyano-4-hydroxy-cinnamic acid (CHCA) and α-cyano-4-chloro-cinnamic acid (CClCA). The choice of the most suitable MALDI matrix is fundamental for high-throughput screening of putative food allergens.

Matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is largely recognized as an important tool in the analysis of many biomolecules such as proteins and peptides. The MS analysis of digested peptides to identify a protein or some of its modifications is a key step in proteomics. MALDI-MS is well suited for the peptide mass fingerprinting (PMF) technique, as well as selected fragmentation of various precursors using collisional-induced dissociation (CID) or post-source decay (PSD).In the last few years, MALDI-MS has played a significant role in food chemistry, especially in the detection of food adulterations, characterization of food allergens, and investigation of protein structural modifications induced by various industrial processes that could be an issue in terms of food quality and safety.Here, we present simple extraction protocols of allergenic proteins in food commodities such as milk, egg, hazelnut , and lupin seeds. Classic bottom-up approaches based on Sodium Dodecyl Sulphate (SDS) gel electrophoresis separation followed by in-gel digestion or direct in-solution digestion of whole samples are described. MALDI-MS and MS /MS analyses are discussed along with a comparison of data obtained by using the most widespread matrices for proteomic studies, namely, α-cyano-4-hydroxy-cinnamic acid (CHCA) and α-cyano-4-chloro-cinnamic acid (CClCA). The choice of the most suitable MALDI matrix is fundamental for high-throughput screening of putative food allergens.

Rationale Cisplatin (CP) is a widely used anticancer drug characterized by toxic side effects that could be alleviated using novel delivery systems including CP prodrugs. The in vitro incubation of a putative prodrug, obtained from cyanocobalamin (CNCbl) and cis-diamminemonochloroplatinum(II) (mCP), with nucleoside monophosphates (NMPs) was investigated. Methods The in vitro reactions between the putative prodrug CNCbl-mCP and the NMPs of adenosine (AMP), guanosine (GMP), cytidine (CMP) and uridine (UMP) were carried out in slightly acidic water-methanol solutions at 37°C for 24 h. Each sample was examined using reversed-phase liquid chromatography coupled with electrospray ionization in positive ion mode and tandem mass spectrometry (RPLC/ESI-MS/MS) by collision-induced dissociation in a linear ion-trap mass spectrometer. Results Seven adducts were recognized as formed by substitution reactions of the chloride ligand in planar CP. Comparison between observed and theoretical isotopic patterns together with MS/MS fragmentation pathways revealed the presence of single or multiple binding sites depending on the NMP involved. The CNCbl-mCP conjugate was found to interact with N7 or O4 atoms of GMP and UMP, respectively, generating single adducts, while two isomeric adducts were observed for CMP. Finally, AMP gave rise to three isomeric adducts. Conclusions In agreement with literature data relevant to the interaction between CP and NMPs, the most reactive nucleotides were AMP and GMP. The present RPLC/ESI-MS/MS approach is very promising for investigation of the reactions of CP conjugates with ribonucleotides not only in vitro but also in vivo.

Nitrate and nitrite as sodium or potassium salts are usually added to meat products to develop the characteristic flavor, to inhibit the growth of microorganisms (particularly Clostridium botulinum), and effectively control rancidity by inhibiting lipid oxidation. However, both nitrate and nitrite ions need to be monitored for ensuring the quality and safety of cured meats. In this work, for the first time the content of nitrite and nitrate ions in homogenized meat samples of baby foods was determined by a validated method based on ion chromatography (IC) coupled with conductivity detection. Recoveries of nitrate and nitrite ions in meat samples were not lower than 84 &plusmn, 6%. The detection limits of nitrate and nitrite were 0.08 mg L&minus, 1 and 0.13 mg L&minus, 1, respectively. Five commercial samples of homogenized meat, namely lamb, rabbit, chicken, veal, and beef, for infant feeding were investigated, while nitrite content was below the detection limit, nitrate ranged from 10.7 to 21.0 mg kg&minus, 1. The results indicated that nitrate contents were below the European (EU) fixed value of 200 mg kg&minus, 1, and an acceptable daily intake of 3.7 mg kg&minus, 1 was estimated.

Lipidomics suffers from the lack of fast and reproducible tools to obtain both structural information on intact phospholipids (PL) and fatty acyl chain composition. Hydrophilic interaction liquid chromatography with electrospray ionization coupled to an orbital-trap Fourier-transform analyzer operating using all ion fragmentation mode (HILIC-ESI-FTMS-AIF MS) is seemingly a valuable resource in this respect. Here, accurate m/z values, HILIC retention times and AIF MS scan data were combined for PL assignment in standard mixtures or real lipid extracts. AIF scans in both positive and negative ESI mode, achieved using collisional induced dissociation for fragmentation, were applied to identify both the head-group of each PL class and the fatty acyl chains, respectively. An advantage of the AIF approach was the concurrent collection of tandem MS-like data, enabling the identification of linked fatty acyl chains of precursor phospholipids through the corresponding carboxylate anions. To illustrate the ability of AIF in the field of lipidomics, two different types of real samples, i.e., the lipid extracts obtained from human plasma and dermal fibroblasts, were examined. Using AIF scans, a total of 253 intact lipid species and 18 fatty acids across 4 lipid classes were recognized in plasma samples, while FA C20:3 was confirmed as the fatty acyl chain belonging to phosphatidylinositol, PI 38:3, which was found to be down-regulated in fibroblast samples of Parkinson&rsquo, s disease patients.

The chemical identity of arsenosugar phospholipids (As-PL) as mono- (i.e., lyso, L-As-PL) and diacyl-arsenosugar PL in four edible and common marine alga samples, such as nori (

RATIONALE The anionic surfactants, among which are alkyl ether sulfates (AESs), are the most used class of surfactants in cleansing applications. The negatively charged head group of AESs is a sulfate moiety linked with a variable number of ethylene oxide units, i.e. a polyethylene glycol chain. The hydrophobic part of an AES is constituted by a linear alkyl chain of carbon atoms, generally obtained from natural fatty acids. Coconut oil fatty acids, including the sodium salts of coceth sulfate (CES) with chemical formula Cx Hy (OCH2 CH2 )n OSO3 Na, are widely used as feedstock for AESs synthesis. CES is added to many cleaning products and detergents defined as non-aggressive. Currently, no detailed structural information concerning the alkyl chain length x and, more importantly, the degree of ethoxylation n has been reported. METHODS A commercial standard solution of CES was characterized by tandem mass spectrometry, employing direct injection into the electrospray ionization (ESI) source of a a linear quadrupole ion trap mass spectrometer. RESULTS Two series of oligomeric species, characterized by a C12 and C14 alkyl chains, i.e. [C12 H25 (OCH2 CH2 )nOSO3 ]- and [C14 H29 (OCH2 CH2 )n OSO3 ]- with n ranging from 0 to 7, were successfully identified. The interpretation of these data was very useful for CES identification in three commercial dishwasher cleaning products. CONCLUSIONS Direct injection MS/MS analysis of CES revealed a well-defined molecular weight distribution and allowed the alkyl chain composition and the number of ethylene oxide units to be to identified.

Autism spectrum disorder (ASD) is a broad and heterogeneous group of neurological developmental disorders characterized by impaired social interaction and communication, restricted and repetitive behavioural patterns, and altered sensory processing. Currently, no reliable ASD molecular biomarkers are available. Since immune dysregulation has been supposed to be related with ASD onset and dyslipidaemia has been recognized as an early symptom of biological perturbation, lipid extracts from peripheral blood mononuclear cells (PBMCs), consisting primarily of lymphocytes (T cells, B cells, and NK cells) and monocytes, of 38 children with ASD and their non-autistic siblings were investigated by hydrophilic interaction liquid chromatography (HILIC) coupled with electrospray ionization and Fourier-transform mass spectrometry (ESI-FTMS). Performances of two freeware software for data extraction and processing were compared with acquired reliable data regardless of the used informatics. A reduction of variables from 1460 by the untargeted XCMS to 324 by the semi-untargeted Alex123 software was attained. All-ion fragmentation (AIF) MS scans along with Alex123 software were successfully applied to obtain information related to fatty acyl chain composition of six glycerophospholipid classes occurring in PBMC. Principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were explored to verify the occurrence of significant differences in the lipid pool composition of ASD children compared with 36 healthy siblings. After rigorous statistical validation, we conclude that phospholipids extracted from PBMC of children affected by ASD do not exhibit diagnostic biomarkers. Yet interindividual variability comes forth from this study as the dominant effect in keeping with the existing phenotypic and etiological heterogeneity among ASD individuals. Graphical abstract.

An extensive characterization and quantification of intact phospholipids (PLs) in strawberry (Fragaria × ananassa cv San Andreas) seed and pulp was carried out by hydrophilic interaction liquid chromatography (HILIC) and electrospray ionization (ESI) coupled to either Fourier-transform (FT) orbital-trap or linear ion-trap tandem mass spectrometry (LIT-MS/MS). More than 150 intact polar lipids including phosphatidylcholines (PCs), phosphatidylethanolamines (PEs), phosphatidylglycerols (PGs), phosphatidic acids (PAs), phosphatidylinositols (PIs), lysophosphatidylcholines (LPCs), and lysophosphatidylethanolamines (LPEs) were identified in negative ESI mode. PC 18:2/18:2 and 18:2/18:3 were found to be the major components of strawberry lipid extracts at concentrations of 230 ± 36 and 189 ± 32 μg/g, respectively, in seeds and at concentrations of 330 ± 50 and 140 ± 22 μg/g, respectively, in pulp. The lipidic extracts of both strawberry seeds and pulp exhibited the dominance of LPC 16:0/0:0 at a content of 132 ± 19 and 114 ± 16 μg/g, respectively, and LPC 0:0/18:2 at 236 ± 20 and 150 ± 20 μg/g, respectively. The other most abundant species of strawberry seeds and pulp were PE 18:2/18:2, 40 ± 9 and 190 ± 40 μg/g, followed by PI 16:0/18:2, 51 ± 15 and 24 ± 8 μg/g, respectively, while PG, PA, and LPE show comparable abundance below 10 μg/g. The most recurrent fatty acyl substituents of PLs were C18:3 (α-linolenic acid), C18:2 (linoleic acid), C18:1 (oleic acid), C18:0 (stearic acid), C16:0 (palmitic acid), and relatively high contents of a shorter chain such as C14:0 (myristic acid).