Performance Liquid Chromatography-electrospray Ionization-tandem Mass Research Articles

Development of a high-throughput liquid chromatography-tandem mass spectrometry platform for the determination of intact natriuretic peptides in human plasma

We present an innovative, reliable, and antibody-free analytical method to determine multiple intact natriuretic peptides in human plasma. These biomolecules are routinely used to confirm the diagnosis and monitor the evolution of heart failure, so that their determination is essential to improve diagnosis and monitor the efficacy of treatment. However, common immunoassay kits suffer from main limitations due to high cross-reactivity with structurally similar species. In our method, we pre-treated the sample by combining salting-out with ammonium sulfate with microextraction by packed sorbent technique. Analyses were then carried out by ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry. The use of 3-nitrobenzyl alcohol as a supercharger reagent enhanced the ESI ionization and improved the signal-to-noise ratio. The analytical protocol showed good linearity over one order of magnitude, recovery in the range of 94–105 %, and good intra- and inter-day reproducibility (RSD<20 %), and the presence of a matrix effect. Limits of detection were in the range of pg/mL for all peptides (0.2–20 pg/mL). Stability study in plasma samples demonstrated that proper protease inhibitors need to be included in blood collection tubes to avoid peptide degradation. Preliminary analyses on plasma samples from heart failure patients allow the quantification of ANP 1–28 as the most abundant species and the detection of ANP 5–28, BNP 1–32, and BNP 5–32. The method could be used to investigate how cross-reactivity issues among structurally similar species impact determinations by ELISA kits.

Phthalate exposure and blood pressure in U.S. children aged 8–17 years (NHANES 2013–2018)

BackgroundCurrent evidence from epidemiologic studies suggested that phthalate metabolites might be associated with blood pressure (BP) changes. However, the special relationship between phthalate metabolites and BP changes in children has not been clearly elucidated in existing researches.ObjectivesWe investigated the links between phthalate metabolites and various BP parameters, including systolic/diastolic BP, mean arterial pressure (MAP), and the presence of hypertension.MethodsThe population sample consisted of 1036 children aged 8 to 17 years from the 2013–2018 NHANES in the United States. High performance liquid chromatography-electrospray ionization-tandem mass spectrometry was used to measure urinary concentrations of 19 phthalate metabolites. Systolic/diastolic BP were derived from the average of three valid measurements, and MAP was calculated as (systolic BP + 2 × diastolic BP)/3. Hypertension was defined as mean systolic BP and/or diastolic BP that was ≥ 95th percentile for gender, age, and height reference. Linear regression, logistic regression, and weighted quantile sum (WQS) regression models were employed to assess the associations between phthalate exposure and systolic/diastolic BP, MAP, and hypertension.ResultsTen of 19 phthalate metabolites including MCNP, MCOP, MECPP, MBP, MCPP, MEP, MEHHP, MiBP, MEOHP, and MBzP had detection frequencies > 85% with samples more than 1000. MCNP, MCOP, MECPP, MBP, MCPP, MEHHP, MiBP, MEOHP, and MBzP were generally negatively associated with systolic/diastolic BP and MAP, but not protective factors for hypertension. These associations were not modified by age (8–12 and 13–17 years) or sex (boys and girls). The above-mentioned associations were further confirmed by the application of the WQS analysis, and MCOP was identified as the chemical with the highest weight.ConclusionPhthalate metabolites were associated with modest reductions in systolic/diastolic BP, and MAP in children, while appeared not protective factors for hypertension. Given the inconsistent results among existing studies, our findings should be confirmed by other cohort studies.

UPLC-ESI-MS/MS-based widely targeted metabolomics reveals differences in metabolite composition among four Ganoderma species.

The Chinese name "Lingzhi" refers to Ganoderma genus, which are increasingly used in the food and medical industries. Ganoderma species are often used interchangeably since the differences in their composition are not known. To find compositional metabolite differences among Ganoderma species, we conducted a widely targeted metabolomics analysis of four commonly used edible and medicinal Ganoderma species based on ultra performance liquid chromatography-electrospray ionization-tandem mass spectrometry. Through pairwise comparisons, we identified 575-764 significant differential metabolites among the species, most of which exhibited large fold differences. We screened and analyzed the composition and functionality of the advantageous metabolites in each species. Ganoderma lingzhi advantageous metabolites were mostly related to amino acids and derivatives, as well as terpenes, G. sinense to terpenes, and G. leucocontextum and G. tsugae to nucleotides and derivatives, alkaloids, and lipids. Network pharmacological analysis showed that SRC, GAPDH, TNF, and AKT1 were the key targets of high-degree advantage metabolites among the four Ganoderma species. Analysis of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes demonstrated that the advantage metabolites in the four Ganoderma species may regulate and participate in signaling pathways associated with diverse cancers, Alzheimer's disease, and diabetes. Our findings contribute to more targeted development of Ganoderma products in the food and medical industries.

Chemical profiling of principle active and toxic constituents in herbs containing aristolochic acids

ObjectiveTo clear the amounts of the principal active/toxic components in herbs containing aristolochic acids (HCAAs), which are still used as medicine and/or seasoning in many ethnic minority areas of China. MethodsIn this study, six major active and toxic components in HCAAs were extracted with ultrasonic extraction. With 6-O-methyl guanosine as internal standard, the target compounds were analyzed qualitatively and quantitatively by using ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS) with multiple reaction monitoring-information dependent acquisition-enhanced production ion scanning mode (MRM-IDA-EPI) combined with dynamic background subtraction (DBS) function. ResultsThe method showed good linearity in the linear range of the six analytes. The limit range of detection was from 0.01 ng/mL to 0.27 ng/mL. All of the detection repeatability, extraction repeatability and accuracy of the method were good. After extraction, the samples remained stable at 15 °C within 24 h. Six analytes were all found in samples except aristolactam (AL) in sample 2, and the contents varied greatly. The contents of these compounds decreased in fruits, leaves and stems of Aristolochia delavayi successively. ConclusionThis method has the advantages of less sample dosage, simple operation, short analysis cycle, high sensitivity, specificity and accuracy. It laid a good foundation for guiding the safety of HCAAs, the in-depth study of pharmacological and toxicological effects and the scientific and standardized processing and compatibility of HCAAs.

Rapid screening and in vivo target occupancy quantitative evaluation of xanthine oxidase inhibitors based on drug-target binding kinetics research strategy: A case study of Chrysanthemum morifolium Ramat.

Chrysanthemum morifolium Ramat. is a kind of food and drug dual-use traditional Chinese medicine possessing multiple pharmacological and biochemical benefits. In our study, a rapid and high-throughput method based on Surface plasmon resonance (SPR) biosensor technology was developed and verified for screening potential xanthine oxidase (XOD) inhibitors exemplarily in the Chrysanthemum morifolium Ramat. Coupled with ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS), 14 XOD-binders were identified. In the SPR-based biosensor and molecular docking analysis, most compounds exhibited a strong affinity and binding kinetic property (association rate constant, Kon and dissociation rate constant, Koff) for XOD and could be regarded as potential inhibitors. More importantly, to further accurately assess target occupancy of candidate compounds in vivo, a mathematical model was established and verified involving three crucial intrinsic kinetic processes (Pharmacokinetics, Binding kinetic and Target kinetic). Overall, the proposed screening and assessment strategy could be proved an effective theoretical basis for further pharmacodynamic evaluation.

Metabolism of eriocitrin in the gut and its regulation on gut microbiota in mice.

Eriocitrin, found in lemon fruit, has shown a wide range of biological properties. Herein, we investigated the intestinal metabolic profile of eriocitrin in colon, and the regulation of dietary intervention of eriocitrin on gut microbiota. We performed ultra performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UPLC-ESI-MS/MS), 16S rDNA gene sequencing and gas chromatography-mass (GC-MS) on colon contents from the eriocitrin group (n=6), and compared them with control participants (n=6). A total of 136 flavonoids were found in colon contents, including eriocitrin and its six metabolites (eriodictyol, homoeriodictyol, hesperetin, eriodictyol-3'-O-glucoside, hesperetin-7-O-glucoside and eriodictyol-7-O-(6″-O-galloyl) glucoside). Moreover, dietary intervention of eriocitrin significantly alters the beta diversity of the gut microbiota, the probiotics such as Lachnospiraceae_UCG_006 were significantly enriched, and the production of butyrate, valerate and hexanoate in the colon pool of short-chain fatty acids were significant increased. The spearman's association analysis performed some intestinal bacteria may be involved in the metabolism of eriocitrin. Collectively, our results preliminarily suggest the metabolism of eriocitrin in the gut, demonstrating alterations of eriocitrin in gut microbiota, which warrants further investigation to determine its potential use in food and biomedical applications.

Validated QuEChERS-based UHPLC-ESI-MS/MS method for the postharvest control of patulin (mycotoxin) contamination in red-pigmented fruits

The paper outlines a procedure based on ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry and QuEChERS pretreatment for the determination of patulin in selected berries and stone fruits. The mycotoxin was determined in the positive electrospray ionization mode utilizing the formation of its methanol adduct. The method was validated for 4 fruit matrices: strawberry (Rosaceae, Fragaria), raspberry (Rosaceae, Rubus), redcurrant (Rosaceae, Prunus) and sour cherry (Grossulariaceae, Ribes). The fruits were characterized by total phenolics, flavonoids, and anthocyanin contents and obtained results were within the ranges of 2.65–11.22 mg GAE/g, 1.06–4.67 mg CE/g, 0.05–1.44 mg cyd-3-glu/g, respectively. The limits of quantification ranged from 0.65 µg/kg to 3.01 µg/kg depending on the fruit type. The method was applied to 71 fruit samples collected in Poland. Analysis of moldy fruit samples has shown a high incidence of patulin contamination.

Simultaneous determination of deuterium-labeled ergosterol and brassicasterol in stroke-prone spontaneously hypertensive rats by ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry.

A previous study has shown that brassicasterol-d1 was detected in the serum of stroke-prone spontaneously hypertensive rats after oral administration of ergosterol-d1. To quantitatively evaluate the serum concentration of brassicasterol-d1, an ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry method was developed for the simultaneous determination of picolinyl ester-derivatized ergosterol-d1 and brassicasterol-d1. The separation was performed on an ODS column (Waters Acquity UPLC BEH C18) with a mobile phase consisting of methanol and water containing 0.1% acetic acid (95/5, v/v). Linear calibration curves in the presence of the serum were obtained in a concentration range of 0.04-8 μg mL-1. Recovery rates of 95.6-119% were obtained with an RSD (n = 6) of less than 7.5%. The method was applied to the determination of time-concentration curves of ergosterol-d1 and brassicasterol-d1 in stroke-prone spontaneously hypertensive rats, showing a pharmacokinetic profile of ergosterol-d1 where the peak serum concentration of brassicasterol-d1 was 3-fold higher than that of ergosterol-d1.

Comparative Analysis of Flavonoid Metabolites in Foxtail Millet (Setaria italica) with Different Eating Quality.

Foxtail millet (Setaria italica) is an important minor cereal crop in China. The yellow color of the de-husked grain is the most direct aspect for evaluating the foxtail millet quality. The yellow pigment mainly includes carotenoids (lutein and zeaxanthin) and flavonoids. To reveal the diversity and specificity of flavonoids in foxtail millet, we chose three high eating quality and two poor eating quality varieties as research materials. A total of 116 flavonoid metabolites were identified based on Ultra Performance Liquid Chromatography-Electrospray Ionization-Tandem Mass Spectrometry (UPLC-ESI-MS/MS) system. The tested varieties contained similar levels of flavonoid metabolites, but with each variety accumulating its unique flavonoid metabolites. A total of 33 flavonoid metabolites were identified as significantly discrepant between high eating quality and poor eating quality varieties, which were mainly in the flavonoid biosynthesis pathway and one of its branches, the flavone and flavonol biosynthesis pathway. These results showed the diversified components of flavonoids accumulated in foxtail millets and laid the foundation for further research on flavonoids and the breeding for high-quality foxtail millet varieties.

Biosynthesis of Lactobionic Acid in Whey-Containing Medium by Microencapsulated and Free Bacteria of Pseudomonas taetrolens

The aim of this research was to develop a method of its production from whey using bacteria of the species Pseudomonas taetrolens. Analyses of the lactobionic acid production method from whey showed that the following factors have a significant effect on its efficiency: the frequency of whey batch feeding, pH and the type of bacteria application, i.e. microencapsulated vs. free. Lactose and lactobionic acid were assayed using high performance liquid chromatography (HPLC) and liquid chromatography-electrospray ionization-tandem mass spectrometry (LC–ESI–MS). The highest concentration of lactobionic acid of 22.03 mg/cm3 was obtained when whey was batch fed at 72-h intervals, pH was maintained at 6.25 and bacteria were enclosed in alginate microcapsules.

Metabolomics Analyses of Cotyledon and Plumule Showing the Potential Domestic Selection in Lotus Breeding

Lotus (Nelumbo nucifera) seeds are widely consumed as functional food or herbal medicine, of which cotyledon (CL) is the main edible part, and lotus plumule (LP) is commonly utilized in traditional Chinese medicine. However, few studies have been conducted to investigate the chemical components of CL and LP in dry lotus seeds, not to mention the comparison between wild and domesticated varieties. In this study, a widely targeted metabolomics approach based on Ultra Performance Liquid Chromatography-electrospray ionization-Tandem mass spectrometry (UPLC-ESI-MS/MS) was utilized to analyze the metabolites in CL and LP of China Antique (“CA”, a wild variety) and Jianxuan-17 (“JX”, a popular cultivar). A total of 402 metabolites were identified, which included flavonoids (23.08% to 27.84%), amino acids and derivatives (14.18–16.57%), phenolic acids (11.49–12.63%), and lipids (9.14–10.95%). These metabolites were classified into ten clusters based on their organ or cultivar-specific characters. Most of these metabolites were more abundant in LP than in CL for both varieties, except for metabolites belonging to organic acids and lipids. The analysis of differentially accumulated metabolites (DAMs) demonstrated that more than 25% of metabolites detected in our study were DAMs in CL and LP comparing “JX” with “CA”, most of which were less abundant in “JX”, including 35 flavonoids in LP, 23 amino acids and derivatives in CL, 7 alkaloids in CL, and 10 nucleotides and derivatives in LP, whereas all of 11 differentially accumulated lipids in LP were more abundant in “JX”. Together with the fact that the seed yield of “JX” is much higher than that of “CA”, these results indicated that abundant metabolites, especially the functional secondary metabolites (mainly flavonoids and alkaloids), were lost during the process of breeding selection.

Development of a highly sensitive method for the quantitative analysis of modified nucleosides using UHPLC-UniSpray-MS/MS

There are more than 150 types of naturally occurring modified nucleosides, which are believed to be involved in various biological processes. Recently, an ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) technique has been developed to measure low levels of modified nucleosides. A comprehensive analysis of modified nucleosides will lead to a better understanding of intracellular ribonucleic acid modification, but this analysis requires high-sensitivity measurements. In this perspective, we established a highly sensitive and quantitative method using the newly developed ion source, UniSpray. A mass spectrometer was used with a UniSpray source in positive ion mode. Our UHPLC-UniSpray-MS/MS methodology separated and detected the four major nucleosides, 42 modified nucleosides, and dG15N5 (internal standard) in 15 min. The UniSpray method provided good correlation coefficients (>0.99) for all analyzed nucleosides, and a wide range of linearity for 35 of the 46 nucleosides. Additionally, the accuracy and precision values satisfied the criteria of <15% for higher concentrations and <20% for the lowest concentrations of all nucleosides. We also investigated whether this method could measure nucleosides in biological samples using mouse tissues and non-small cell lung cancer clinical specimens. We were able to detect 43 and 31 different modified nucleosides from mouse and clinical tissues, respectively. We also found significant differences in the levels of N6-methyl-N6-threonylcarbamoyladenosine (m6t6A), 1-methylinosine (m1I), 2′-O-methylcytidine (Cm), 5-carbamoylmethyluridine (ncm5U), 5-methoxycarbonylmethyl-2-thiouridine (mcm5S2U), and 5-methoxycarbonylmethyl-2′-O-methyluridine (mcm5Um) between cancerous and noncancerous tissues. In conclusion, we developed a highly sensitive methodology using UHPLC-UniSpray-MS/MS to simultaneously detect and quantify modified nucleosides, which can be used for analysis of biological samples.

Lipidomic Signatures of Post-Hepatectomy Liver Failure Using Porcine Hepatectomy Models

Introduction: Clinical diagnosis of post-hepatectomy liver failure (PHLF) can only be made on or after 5th postoperative day. Biomarker for early diagnosis is considered as a critical unmet need. Method: Pigs underwent sham operation (n=6), 70% (n=7) and 90% (n=7) partial hepatectomy (PH). A comprehensive lipidomic analysis was conducted using sera collected at pre-operation (PO), 14 h, 30 h, and 48 h after PH using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry. Results: Of the 184 quantified lipids, 14 lipids showed significant differences between the two resection groups starting at 30 h after surgery. Four phosphatidylcholine (PC) plasmalogen species (p-16:0/16:0, p-18:0/18:2, p-18:0/20:4, and p-18:0/22:6) and PC 32:2 significantly increased in the 90% PH group while these returned to PO level after 30 h in the 70% PH group, presumably implying the failure markers. However, eight triacylglycerol (TG) species (40:0, 42:1, 42:0, 44:1, 44:2, 46:1, 46:2, and 48:3) and sphingomyelin d18:1/20:0 showed an opposite trend, wherein they significantly decreased in the 90% PH group while these in the 70% PH group were abruptly increased until 30 h but returned to near PO levels at 48 h , implying the recovery markers. Same trends were also observed in PC plasmalogen and TG classes in addition to selected individual lipid species. Conclusions: Characteristic lipidomic signatures of PHLF could be identified using large animal models. These candidates have potentials to serve as a tool for early diagnosis and may open new path to the study to overcome PHLF.

Lipidomic signatures of post-hepatectomy liver failure using porcine hepatectomy models.

BackgroundClinical diagnosis of post-hepatectomy liver failure (PHLF) can only be made on or after the 5th postoperative day. Biomarker for early diagnosis is considered as a critical unmet need.MethodsTwenty domestic female crossbreed (Yorkshire-landrace and duroc) pigs underwent sham operation (n=6), 70% (n=7) and 90% (n=7) partial hepatectomy (PH). A comprehensive lipidomic analysis was conducted using sera collected at pre-operation (PO), 14, 30, and 48 h after PH using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry.ResultsOf the 184 quantified lipids, 14 lipids showed significant differences between the two resection groups starting at 30 h after surgery. Four phosphatidylcholine (PC) plasmalogen species (P-16:0/16:0, P-18:0/18:2, P-18:0/20:4, and P-18:0/22:6) and PC 32:2 significantly increased in the 90% PH group while these returned to PO level after 30 h in the 70% PH group, presumably implying the failure markers. In contrast, eight triacylglycerol (TG) species (40:0, 42:1, 42:0, 44:1, 44:2, 46:1, 46:2, and 48:3) and sphingomyelin d18:1/20:0 showed an opposite trend, wherein they significantly decreased in the 90% PH group while these in the 70% PH group were abruptly increased until 30 h but returned to near PO levels at 48 h, implying the recovery markers. Same trends could also be observed in the level of whole lipid classes of PC plasmalogens and TGs, in addition to selected individual lipid species.ConclusionsCharacteristic lipidomic signatures of PHLF could be identified using large animal models. These candidates have a potential to serve as a tool for early diagnosis and may open new paths to the study to overcome PHLF.

The application of in-source fragmentation in ultra-high performance liquid chromatography-electrospray ionization -tandem mass spectrometry for pesticide residue analysis

In this study, in-source fragmentation in ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) was investigated and applied for pesticide residue analysis. Over 400 pesticides were tested, among which 26 pesticides were found to be sensitive to in-source fragmentation, producing 33 in-source fragments. The fragment pathways were studied and severe in-source fragmentation was observed due to the cleavage of C-O bond of carbamate, phosphate, ester, and ether groups, especially for isocarbophos and methoprene, leading to false negative results. High source temperatures could significantly increase the extent of in-source fragmentation. A multiple reaction monitoring (MRM) based multiresidue method was established for the pesticide residue analysis in vegetables and fruits, applying both pesticides and in-source fragments as precursors. The quantification ability of the method was validated and compared in terms of recovery, linearity, and the limit of quantification. In-source fragmentswere found to be more suitable than their parent pesticides as precursor ions for MRM analysis.

Simultaneous quantification of the lipids phosphatidylcholine, 3-sn-phosphatidylethanolamine, sphingomyelin, and L-α-lysophosphatidylcholine extracted from the tissues of the invasive golden apple snail (Pomacea canaliculata) using UHPLC-ESI-MS/MS

Lipids such as phosphatidylcholine (PC), 3-sn-phosphatidylethanolamine (PE), sphingomyelin (SM) and L-α-lysophosphatidylcholine (LPC) are the major components of biological membranes and play important roles in physiological functions. Here, PC, PE, SM, and LPC were extracted from golden apple snails (GAS, Pomacea canaliculata) and GAS flesh (GASF) using an ethanol/hexane sequential scheme and quantified simultaneously using ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) to evaluate whether the GAS could be the source of the four lipids. Our results suggest that ethanol extracts contained the most crude lipids, and the yield of dry (evaporated) lipids were 3.45 g per 100 g fresh GASF and 1.82 g per 100 g of fresh GAS. Quantification of the lipids using UHPLC-ESI-MS/MS suggested that GAS contained PE, PC, SM and LPC, with SM being the most abundant lipid (after purification: 1.71 and 1.42 mg g−1 dry weight from 100 g of GASF and GAS, respectively). The method we used is cost-effective, and the recovery rates of ethanol and hexane ranged from 80−91% and 87−91% respectively. Overall, GAS and GASF are potential raw materials for lipids such as SM and PC extraction using the ethanol/hexane method. Comparatively, lipids extraction from the GAS is more effective and timesaving. Our finding would provide a way to utilize GAS and potentially control its invasion.

Exercise-induced recovery of plasma lipids perturbed by ageing with nanoflow UHPLC-ESI-MS/MS.

Daily physical exercise is an essential part of life and is required for remaining healthy; it enhances therapeutic efficacy in the elderly and prevents age-related diseases associated with lipid profile alterations, such as cardiovascular disease, diabetes mellitus, and dementia. To more efficiently analyse the lipid profiles and unveil the effect of exercise in aged mice, we optimized our study by examining the effects of using ionization modifiers in the mobile phase and in-source fragmentation of lysophospholipids on the simultaneous analysis of fatty acids (FAs) including hydroxyl fatty acids, glycerophospholipids, sphingolipids, and glycerolipids using nanoflow ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry. We applied the optimization to investigate the lipidomic plasma alterations in young (7weeks old) and aged (84weeks old) mice (C57BL/6) subjected to treadmill exercise. Of the 390 identified lipid species, 159 were quantified to investigate ageing-related lipid species responsive to physical exercise. In particular, circulating lysophosphatidylcholine and lysophosphatidylethanolamine levels showed a significant decrease, and lysophosphatidic acid showed a simultaneous increase with ageing. The saturated FA (16:0 and 18:0) increased with ageing while the unsaturated FA 22:6 decreased. Dihydroxy fatty acid (18:1_2OH) showed an exercise-induced recovery against ageing. It is notable that the levels of five triacylglycerol species significantly increased by as much as threefold with ageing, but their levels largely recovered to those observed in the young mice after exercise. These findings can help understand the influence of ageing on lipid perturbation and the role of physical exercise on lipidomic recovery in response to ageing-associated loss of physical status. Graphical abstract.

Phytochemical Characterization and Effects on Cell Proliferation of Lentisk (Pistacia lentiscus) Berry Oil: a Revalued Source of Phenolics.

The ethno-pharmaceutical use of the edible fixed oil produced from lentisk (Pistacia lentiscus) berries covers a long tradition in several Mediterranean regions. Many of the health-promoting properties of lentisk berry oil (LBO) have been associated with the content of polar (poly)phenolic compounds. However, the polar fraction (methanol 80%, v/v) of LBO (LBO-pf) remains poorly and inadequately characterized. We assessed the phytochemical composition (fatty acids, phytosterols and polyphenols) of cold-pressed LBO produced in Cilento (Campania region, Italy) over four years of production (2015-2018). Main phenolic compounds present in LBO-pf were identified and semi-quantified combining ultra-high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) and HPLC with diode array detection. Phenolic compounds, also responsible for oil stability and antioxidant properties, are relatively abundant in LBO, compared to other edible oils. LBO-pf induced clear dose-dependent effects on the growth of HT-29 cell line derived from human colorectal adenocarcinoma, as evidenced by the cell cycle arrest. Our data support the health-promoting properties of cold-pressed LBO, which is obtained with good yield from spontaneous plants growing in semiarid regions.

Perturbations of Lipids and Oxidized Phospholipids in Lipoproteins of Patients with Postmenopausal Osteoporosis Evaluated by Asymmetrical Flow Field-Flow Fractionation and Nanoflow UHPLC-ESI-MS/MS.

Osteoporosis, a degenerative bone disease characterized by reduced bone mass and high risk of fragility, is associated with the alteration of circulating lipids, especially oxidized phospholipids (Ox-PLs). This study evaluated the lipidomic changes in lipoproteins of patients with postmenopausal osteoporosis (PMOp) vs. postmenopausal healthy controls. High-density lipoproteins (HDL) and low-density lipoproteins (LDL) from plasma samples were size-sorted by asymmetrical flow field-flow fractionation (AF4). Lipids from each lipoprotein were analyzed by nanoflow ultrahigh performance liquid chromatography–electrospray ionization–tandem mass spectrometry (nUHPLC–ESI–MS/MS). A significant difference was observed in a subset of lipids, most of which were increased in patients with PMOp, when compared to control. Phosphatidylethanolamine plasmalogen, which plays an antioxidative role, was increased in both lipoproteins (P-16:0/20:4, P-18:0/20:4, and P-18:1/20:4) lysophosphatidic acid 16:0, and six phosphatidylcholines were largely increased in HDL, but triacylglycerols (50:4 and 54:6) and overall ceramide levels were significantly increased only in LDL of patients with PMOp. Further investigation of 33 Ox-PLs showed significant lipid oxidation in PLs with highly unsaturated acyl chains, which were decreased in LDL of patients with PMOp. The present study demonstrated that AF4 with nUHPLC–ESI–MS/MS can be utilized to systematically profile Ox-PLs in the LDL of patients with PMOp.

A validated UHPLC-MS/MS method for simultaneous quantification of 9 exocyclic DNA adducts induced by 8 aldehydes

Human exposure to aldehydes is implicated in several diseases including cancer. These strong electrophilic compounds can react with nucleophilic sites in DNA to form reversible and irreversible modifications. These modifications, if not repaired, can contribute to pathogenesis. The aim of our study was to provide a mass spectrometry (MS)-based profiling method for identifying potential biomarkers of aldehydes exposure. We have developed and validated a highly sensitive method using ultra high performance liquid chromatography-electrospray ionization-tandem mass spectrometry (UHPLC-ESI-MS/MS) for the simultaneous quantitation of 9 exocyclic DNA adducts derived from 8 main exogenous and endogenous aldehydes, namely formaldehyde, acetaldehyde, acrolein, crotonaldehyde, malondialdehyde, 4-hydroxy-2-nonenal, glyoxal and methylglyoxal. Finally, we applied the established method to quantify adducts in genomic DNA isolated from the blood of a smoker and a non-smoker blood samples in order to demonstrate its applicability.