Gas-Phase Fragmentation of Coenzyme Q Radical Anion Generated by APCI: A Study by High/Low-Resolution Tandem/Sequential Mass Spectrometry.

Coenzyme Q (CoQ) and closely related compounds with varying isoprenoid tail lengths (CoQ, = 6-9) are biochemical cofactors involved in many physiological processes, playing important roles in cellular respiration and energy production. Liquid chromatography (LC) coupled with single or tandem mass spectrometry (MS) using electrospray (ESI) or atmospheric pressure chemical ionization (APCI) is considered the gold standard for the identification and quantification of CoQ in food and biological samples. However, the characteristic fragmentation exhibited by the CoQ radical anion ([M], / 862.

4D-DIA Proteomics Uncovers New Insights into Host Salivary Response Following SARS-CoV-2 Omicron Infection.

Since late 2021, Omicron variants have dominated the epidemiological scenario as the most successful severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sublineages, driving new and breakthrough infections globally over the past two years. In this study, we investigated for the first time the host salivary response of COVID-19 patients infected with Omicron variants (BA.1, BA.

Confirmation of the unexpected occurrence of bitterness-inducing cucurbitacins in edible unripe melons by a two-step workflow based on liquid chromatography with combined UV and high-resolution MS detection.

Plant metabolites known as cucurbitacins are known to impart an unpleasant bitter taste to edible fruits and even lead to severe health complications after the ingestion of relatively high amounts. In this study, an analytical method based on reversed phase liquid chromatography with combined detection by UV spectroscopy and atmospheric pressure chemical ionization high-resolution single/tandem mass spectrometry was applied to confirm the occurrence of four cucurbitacins (B, D, and R, and 23,24-dihydro cucurbitacin B) previously inferred in unexpectedly bitter-tasting fruits of an Italian variety (Scopatizzo) of unripe melon (Cucumis melo L.), known for the sweetness of its fruits.

Look but don't touch: Non-invasive chemical analysis of organic paint binders - A review.

Diagnostics on historical art samples are decisive for assessing degradation and understanding the chemical composition of supports and polychromies. These investigations help us in uncovering the artist's style and techniques and provide invaluable information for restoration, preservation and conservation. In paint formulation, the binder, also known as medium, disperses insoluble pigments and creates a homogeneous, adhesive mixture.

Tandem Mass Spectrometry in Untargeted Lipidomics: A Case Study of Peripheral Blood Mononuclear Cells.

Peripheral blood mononuclear cells (PBMCs), including lymphocytes, are important components of the human immune system. These cells contain a diverse array of lipids, primarily glycerophospholipids (GPs) and sphingolipids (SPs), which play essential roles in cellular structure, signaling, and programmed cell death. This study presents a detailed analysis of GP and SP profiles in human PBMC samples using tandem mass spectrometry (MS/MS).

Integrating Epoxidation, High-Resolution Mass Spectrometry and Ultraviolet Spectroscopy to Unravel the Complex Profile of Boswellic Acids and Related Compounds in the Gum Resin Extract.

The chemical characterization of natural products is often a complex task that demands powerful analytical techniques. Liquid chromatography with high-resolution tandem mass spectrometry (HRMS/MS) is often employed, yet it can face hard challenges when isomeric species are present, and reference standards are lacking. In such cases, the confidence level in compound identification can be significantly improved by the collection of orthogonal information on target analytes.

Corpus luteum proximity alters molecular signature of the small extracellular vesicles and cumulus cells in the bovine ovarian follicle environment.

Progesterone (P4) is predicted to act as a negative regulatory hormone for oocyte maturation events; however, its local effects during follicular development remain poorly understood in bovine. The complex process of oocyte meiosis progression is dependent on cellular communication among follicular cells. Besides, the breakdown of this communication, mainly between cumulus cells (CC) and oocyte, through the retraction of cumulus projections connecting these cells can impact oocyte maturation.

Discovering the Ellagitannin Landscape of Dried Walnut Shells by Liquid Chromatography with Tandem Mass Spectrometry.

Walnut shells, often discarded as waste, hold hidden potential as a source of ellagitannins (ETs), compounds known for their promising antioxidant properties and health benefits. This study employed reversed-phase liquid chromatography (RPLC) coupled with Orbitrap-based high-resolution mass spectrometry (HRMS) via electrospray ionization (ESI) in negative polarity to investigate the ET profile in extracts of dried powdered walnut shells. Several compounds belonging to various ET families were successfully identified as deprotonated molecules ([M - H]) and characterized, including mono-, di-, tri-, tetra-, and pentagalloyl glucopyranoses, as well as ETs containing the hexahydroxydiphenoyl (HHDP) group.

Proteomics for Microalgae Extracts by High-Resolution Mass Spectrometry.

Two protocols of protein extraction from Arthrospira platensis (spirulina) microalgae to study their proteome by mass spectrometry (MS) are here presented. The first is based on an aqueous buffer solution of Tris-HCl and the second on cold acetone. The identification of proteins was carried out by a bottom-up approach, which involves enzymatic digestion of extracted proteins followed by either matrix-assisted laser desorption ionization with time-of-flight (MALDI-TOF) MS or liquid chromatography (LC) coupled with electrospray ionization (ESI) and Fourier-transform tandem MS.

Mass spectrometric characterization of aminophospholipids containing N-(2-hydroxyethyl)glycine in kombu algae extracts.

Rationale: 1,2-Diacyl-sn-glycero-3-phospho-O-[N-(2-hydroxyethyl)glycines] (PHEGs) are a class of rare aminophospholipids found specifically in brown algae, including kombu seaweed. Despite their potential importance in algal physiology, a comprehensive mass spectrometry (MS) characterization, useful to understand their biological behaviour, is still lacking.

Methods: To establish the structural regiochemical features of PHEGs, we employed hydrophilic interaction liquid chromatography (HILIC).

Development of a New Binary Matrix for the Comprehensive Analysis of Lipids and Pigments in Micro- and Macroalgae Using MALDI-ToF/ToF Mass Spectrometry.

While edible algae might seem low in fat, the lipids they contain are crucial for good health and preventing chronic diseases. This study introduces a binary matrix to analyze all the polar lipids in both macroalgae (Wakame-, Dulse-, and Nori- spp.) and microalgae (Spirulina-, and Chlorella-) using matrix-assisted laser desorption ionization mass spectrometry (MALDI-MS).

Lipidomics reveals the reshaping of the mitochondrial phospholipid profile in cells lacking OPA1 and mitofusins.

Depletion or mutations of key proteins for mitochondrial fusion, like optic atrophy 1 (OPA1) and mitofusins 1 and 2 (Mfn 1 and 2), are known to significantly impact the mitochondrial ultrastructure, suggesting alterations of their membranes' lipid profiles. In order to make an insight into this issue, we used hydrophilic interaction liquid chromatography coupled with electrospray ionization-high resolution MS to investigate the mitochondrial phospholipid (PL) profile of mouse embryonic fibroblasts knocked out for OPA1 and Mfn1/2 genes. One hundred sixty-seven different sum compositions were recognized for the four major PL classes of mitochondria, namely phosphatidylcholines (PCs, 63), phosphatidylethanolamines (55), phosphatidylinositols (21), and cardiolipins (28).

Exploration of the Lipid Profile of Edible Oleaginous Microgreens by Mass Spectrometry-Based Lipidomics.

The spreading awareness of the health benefits associated with the consumption of plant-based foods is fueling the market of innovative vegetable products, including microgreens, recognized as a promising source of bioactive compounds. To evaluate the potential of oleaginous plant microgreens as a source of bioactive fatty acids, gas chromatography-mass spectrometry was exploited to characterize the total fatty acid content of five microgreens, namely, chia, flax, soy, sunflower, and rapeseed (canola). Chia and flax microgreens appeared as interesting sources of α-linolenic acid (ALA), with total concentrations of 2.

Matrix Selection Strategies for MALDI-TOF MS/MS Characterization of Cyclic Tetrapyrroles in Blood and Food Samples.

Cyclic tetrapyrrole derivatives such as porphyrins, chlorins, corrins (compounds with a corrin core), and phthalocyanines are a family of molecules containing four pyrrole rings usually coordinating a metal ion (Mg, Cu, Fe, Zn, etc.). Here, we report the characterization of some representative cyclic tetrapyrrole derivatives by MALDI-ToF/ToF MS analyses, including heme b and c, phthalocyanines, and protoporphyrins after proper matrix selection.

Histologic and proteomic profile of two methods to decellularize human dental pulp tissue.

Objective: The present study compared the structural and proteomic architecture of extracellular matrices (ECM) of decellularized human dental pulp using two previously described protocols.

Design: Pulp tissue from 150 molars was extracted and three treatments took place, based on the Matoug-Elwerfelli Group (MG) and the Song Group (SG) protocols and an untreated pulp group (CG), to examine histoarchitecture and the effectiveness of the decellularization process, using histological analysis (n = 12) and scanning electron microscopy (SEM) (n = 3). Protein extraction took place using 100 mg dry weight of pulp, in triplicates for each group, and the shotgun proteome analysis was performed by nanoUPLC-MS.

Proteomics approach reveals urinary markers for early pregnancy diagnosis in buffaloes.

This study aimed to compare urine proteomics from non- and pregnant buffaloes in order to identify potential biomarkers of early pregnancy. Forty-four females underwent hormonal ovulation synchronization and were randomly divided into two experimental groups: inseminated (n = 30) and non-inseminated (n = 14). The pregnant females were further divided into two groups: pregnant at Day 12 (P12; n = 8) and at Day 18 (P18; n = 8) post-ovulation.

Uterine secretome: What do the proteins say about maternal-fetal communication in buffaloes?

The aim was to compare the UF proteomics of pregnant and non-pregnant buffalo during early pregnancy. Forty-four females were submitted to hormonal estrus synchronization and randomly divided into two groups: pregnant (n = 30) and non-pregnant (n = 14). The pregnant group was artificially inseminated and divided into a further two groups: P12 (n = 15) and P18 (n = 15).

Food allergen detection by mass spectrometry: From common to novel protein ingredients.

Food allergens are molecules, mainly proteins, that trigger immune responses in susceptible individuals upon consumption even when they would otherwise be harmless. Symptoms of a food allergy can range from mild to acute; this last effect is a severe and potentially life-threatening reaction. The European Union (EU) has identified 14 common food allergens, but new allergens are likely to emerge with constantly changing food habits.

The Effect of Milling on the Ethanolic Extract Composition of Dried Walnut ( L.) Shells.

This study investigates the ethanolic extract of dried walnut ( L.) shells upon hammer milling (HM) and ball milling (BM) grinding processes. Marked differences were observed in the attenuated total reflection Fourier-transform infrared (ATR-FTIR) spectra.

Methyl carbamates of phosphatidylethanolamines and phosphatidylserines reveal bacterial contamination in mitochondrial lipid extracts of mouse embryonic fibroblasts.

The occurrence of methyl carbamates of phosphatidylethanolamines and phosphatidylserines in the lipid extract of mitochondria obtained from mouse embryonic fibroblasts was ascertained by hydrophilic interaction liquid chromatography with electrospray ionization single and multi-stage mass spectrometry, performed using sinergically a high resolution (quadrupole-Orbitrap) and a low resolution (linear ion trap) spectrometer. Two possible routes to the synthesis of methyl carbamates of phospholipids were postulated and evaluated: (i) a chemical transformation involving phosgene, occurring as a photooxidation by-product in the chloroform used for lipid extraction, and methanol, also used for the latter; (ii) an enzymatic methoxycarbonylation reaction due to an accidental bacterial contamination, that was unveiled subsequently on the murine mitochondrial sample. A specific lipid extraction performed on a couple of standard phosphatidyl-ethanolamines/-serines, based on purposely photo-oxidized chloroform and deuterated methanol, indicated route (i) as negligible in the specific case, thus highlighting the enzymatic route related to bacterial contamination as the most likely source of methyl carbamates.

Strategies for the analysis of arsenolipids in marine foods: A review.

Arsenic-containing lipids, also named arsenolipids (AsLs), are a group of organic compounds usually found in a variety of marine organisms such as fish, algae, shellfish, marine oils, and microorganisms. Numerous AsLs have been recognised so far, from simple compounds such as arsenic fatty acids (AsFAs), arsenic hydrocarbons (AsHCs), and trimethylarsenio fatty alcohols (TMAsFOHs) to more complex arsenic-containing species, of which arsenophospholipids (AsPLs) are a case in point. Mass spectrometry, both as inductively coupled plasma (ICP-MS) and liquid chromatography coupled by an electrospray source (LC-ESI-MS), was applied to organic arsenicals playing a key role in extending and refining the characterisation of arsenic-containing lipids in marine organisms.

A targeted GC-MS/MS approach for the determination of eight sterols in microgreen and mature plant material.

Over the past decades, a remarkable number of scientific studies supported the correlation between an adequate dietary intake of phytosterols (PS) and the reduced risk of cardiovascular diseases. PS are known to inhibit the intestinal absorption of cholesterol, thus promoting the reduction of the low-density lipoproteins (LDL) amount in the bloodstream. Despite the fact that a non-negligible atherogenicity was recognized to PS, thus requiring a careful risk-benefits assessment for plant sterol supplementation, the potential role of PS as cholesterol-lowering agents has been contributing to the spreading awareness of the health benefits associated with the consumption of plant-based foods.

Uncovering heterogeneity of anacardic acids from pistachio shells: A novel approach for structural characterization.

Anacardic acids (AnAs) are important secondary metabolites that occur primarily in plants of the Anacardiaceae family, such as pistachio (Pistacia vera L.). Some AnAs have been associated with health benefits, and the position of the CC double bonds is a crucial feature of these metabolites.

Oxidative NHC Catalysis: An Unconventional Tool for Macrocyclic Oligoesters Synthesis.

The application of N-heterocyclic carbene (NHC) catalysis under highly diluted oxidative condition to the polycondensation of dialdehydes and diols is herein presented as an alternative, atom-economical synthetic route to macrocyclic oligoesters (MCOs). The disclosed protocol paves the way to the straightforward access to MCOs, starting from commercial dialdehydes, avoiding the use of toxic diacyl chlorides, commonly employed in traditional MCOs synthetic processes. The method is totally metal-free, takes place in the green Me-THF solvent and requires the use of a fully recyclable quinone oxidant.

Type I-like metalloproteinase in the venom of the West African saw-scaled carpet viper (Echis ocellatus) has anti-trypanosomal activity against African trypanosomes.

African trypanosomiasis is an infectious disease caused by hemoparasites of the genus Trypanosoma and remains a major health problem in Africa - killing around 4000 people and animals worth an estimated $5 billion, annually. The absence of a vaccine and satisfactory drug against African trypanosomiasis (AT) necessitates the continued search for new chemotherapy options. Owing to the rich biochemical diversity in snake venom, it has recently become a source of therapeutic peptides that are being explored for the development of novel drug candidates for diverse ailments such as cancers and infectious diseases.