High-resolution Mass Spectrometry Analysis Research Articles

Extreme shifts in pyrite sulfur isotope compositions reveal the path to bonanza gold

Pyrite is the most common sulfide mineral in hydrothermal ore-forming systems. The ubiquity and abundance of pyrite, combined with its ability to record and preserve a history of fluid evolution in crustal environments, make it an ideal mineral for studying the genesis of hydrothermal ore deposits, including those that host critical metals. However, with the exception of boiling, few studies have been able to directly link changes in pyrite chemistry to the processes responsible for bonanza-style gold mineralization. Here, we report the results of high-resolution secondary-ion mass spectrometry and electron microprobe analyses conducted on pyrite from the Brucejack epithermal gold deposit, British Columbia. Our δ34S and trace element results reveal that the Brucejack hydrothermal system experienced abrupt fluctuations in fluid chemistry, which preceded and ultimately coincided with the onset of ultra-high-grade mineralization. We argue that these fluctuations, which include the occurrence of extraordinarily negative δ34S values (e.g., -36.1‰) in zones of auriferous, arsenian pyrite, followed by sharp increases of δ34S values in syn-electrum zones of nonarsenian pyrite, were caused by vigorous, fault valve-induced episodic boiling (flashing) and subsequent inundation of the hydrothermal system by seawater. We conclude that the influx of seawater was the essential step to forming bonanza-grade electrum mineralization by triggering, through the addition of cationic flocculants and cooling, the aggregation of colloidal gold suspensions. Moreover, our study demonstrates the efficacy of employing high-resolution, in situ analytical techniques to map out individual ore-forming events in a hydrothermal system.

Inhibitory mechanism of carboxymethyl cellulose on advanced glycation end products in plant-based meat alternatives

Plant-based meat alternatives (PBMA) were detected with high advanced glycation end products (AGEs) levels in our previous study, threatening human health. In this study, carboxymethyl cellulose (CMC) exhibited excellent inhibitory effects on AGEs in both PBMA and chemical model systems. Moreover, the inhibitory effects were dependent on the levels of CMC addition. With 4% CMC addition, the contents of Nε-carboxymethy-L-lysine (CML) and Nε-carboxyethy-L-lysine (CEL) in PBMA decreased by 75% and 83%, respectively. Through comprehensive characterizations and high-resolution mass spectrometry analysis, three possible inhibitory pathways were proposed at the molecular level: CMC improved the thermal stability of soy protein isolates (SPI) via covalent bond; CMC occupied the amino reaction sites on SPI and competitively inhibited the reaction between SPI and glucose; CMC scavenged the intermediates of AGEs (i.e glyoxal and methylglyoxal). This research lays a theoretical foundation on the inhibition of AGEs in PBMA through the regulation of hydrocolloids.

Ambient mass spectrometry imaging of food natural products by angled direct analysis in real time high-resolution mass spectrometry

Direct surface analysis in ambient conditions provides information on the position and chemical composition of an object at the time of investigation. An angled sampling probe is developed in this work for direct analysis in real time (DART) ionization high-resolution mass spectrometry. The DART ion source and the interface were modified for improved surface resolution, increased ion transfer efficiency, as well as enabling two-dimensional surface scanning. The angled probe DART-MS system was used for investigating a variety of food samples including fruit peels, ginseng root, plant leaves and sections of radish. Abundant signals and distinct chemical profiles are obtained in seconds, and spatial distribution of different molecules across the sample surfaces can be observed. In addition, the developed system can quickly identify the chemical changes when the surfaces were treated. The method is capable of directly evaluating food sample surfaces with different shapes, hardness, and conditions, without any sample pretreatments.

Validation of the traditional antimicrobial use of the Iranian medicinal plant Thymus daenensis Celak through phytochemical characterization of its bioactive constituents

Thymus daenensis Celak (Lamiaceae family), known as denaian thyme, is an Iranian endemic plant, commonly used for its carminative, expectorant, antibacterial and antifungal properties. Previous studies report the chemical profile of the essential oil of T. daenensis aerial parts, but little is known about its non volatile constituents. Herein, phytochemical and biological investigation of the polar extract of T. daenensis aerial parts to provide further insight into traditional use of this plant has been accomplished. High-performance liquid chromatography coupled to linear ion-trap and orbitrap high-resolution mass spectrometry (LC-ESI/LTQOrbitrap/MS/MS) analysis of MeOH extract was performed to guide the isolation of specialized metabolites and successive characterization by NMR analysis. MeOH extract displayed antioxidant activity evaluated by DPPH (EC50 = 48.99 ± 1.47 μg/mL) and TEAC assay (1.37 mg/mL). Successively, the biofilm inhibitory activity of extract and isolated compounds against mature biofilms of Escherichia coli, Pseudomonas aeruginosa, Acinetobacter baumannii, Listeria monocytogenes, and Staphylococcus aureus, and their influence on the metabolism of sessile bacterial cells were evaluated. Two previously unreported thymol derivatives have been identified. The biofilm inhibitory activity of isolated compounds highlighted a promising antimicrobial action for the tested compounds. In particular, vanillic acid, (3S,5R,6R,7E,9S)-megastigm-7-ene-3,5,6,9-tetrol 3-O-β-D-glucopyranoside, thymoquinol-2-O-β-D-glucopyranoside and the never reported compound daenol resulted capable of exerting inhibitory activity vs all pathogenic strains. All compounds tested at a concentration of 10 μg/mL inhibited the metabolism of the sessile cells of E. coli at a percentage ranging between 37.7% and 77.39%, and of L. monocytogenes at a percentage ranging between 21.79% and 71.17%.

Utilizing Derivatizing Agents for the Differentiation of Cannabinoid Isomers in Complex Food, Beverage and Personal-care Product Matrices by Ambient Ionization Mass Spectrometry

Recent legalization and decriminalization of marijuana at the state level has not only contributed to a rise in the recreational use of Cannabis sativa, also known simply as Cannabis, but also to an increase in the range of matrices into which cannabinoids are infused. Traditional methods for analyzing these products, which are typically chromatography-based, are often matrix-dependent and demand time-consuming and resource-intensive sample preparation protocols that are highly nuanced and not readily applicable to multiple matrix types. Furthermore, the differentiation of cannabinoids can be troublesome without implementing lengthy run times to achieve resolution of chromatographic peaks. With complex samples such as edibles, beverages, personal-care products, and plant materials, a method that can be more universally applied to rapidly detect and differentiate between cannabinoids is highly desirable. In this study, foods and personal care products under the categories of sweets, spreads, condiments/toppings, beverages, oils, and commercial body products were spiked with cannabinoids including Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabicitran (CBT), and cannabigerol (CBG). Chemical derivatization of the samples with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) followed by direct analysis in real time – high-resolution mass spectrometry (DART-HRMS) analysis readily revealed the presence of cannabinoids in the products despite the matrix complexity (i.e., the contributions from matrix-derived peaks did not interfere with the differentiation of cannabinoids). When analyzed under ambient soft ionization conditions, CBT, THC and CBD are indistinguishable because they are isomers with a molecular formula of C21H30O2 and a protonated monoisotopic mass of 315.2324. However, due to the different number of hydroxyl (-OH) groups (zero in CBT, one in THC, and two in CBD) that engage with the derivatizing agent, the cannabinoids are differentiated based on the mass disparities of the protonated adducts formed (m/z 315.2324, 387.2719 and 459.3119 for CBT, THC, and CBD, respectively), and which are readily revealed by DART-HRMS. This approach circumvents some of the challenges currently encountered by forensic laboratories in the analysis of highly complex and diverse cannabinoid-infused matrices. The results show proof-of-concept for an approach that can aid in the differentiation of cannabinoid isomers by DART-HRMS that accommodates high matrix diversity and complexity, and demonstrates the potential for the approach to be integrated into current workflows for the forensic analysis of Cannabis-related materials and evidence.

Synthesis and Application of Salicylhydrazone Probes with High Selectivity for Rapid Detection of Cu2.

Using the aldehyde amine condensation procedure and the triphenylamine group as the skeleton structure, the new triphenylamine-aromatic aldehyde-succinylhydrazone probe molecule DHBYMH was created. A newly created acylhydrazone probe was structurally characterized by mass spectrometry (MS), NMR, and infrared spectroscopy (FTIR). Fluorescence and UV spectroscopy were used to examine DHBYMH's sensing capabilities for metal ions. Notably, DHBYMH achieved a detection limit of 1.62 × 10-7 M by demonstrating exceptional selectivity and sensitivity towards Cu2+ ions in an optimum sample solvent system (DMSO/H2O, (v/v = 7/3); pH = 7.0; cysteine (Cys) concentration: 1 × 10-4 M). NMR titration, high-resolution mass spectrometry analysis, and DFT computation were used to clarify the response mechanism. Ultimately, predicated on DHBYMH's reversible identification of Cu2+ ions in the presence of EDTA, a molecular logic gate was successfully designed.

First report on glucocerebrosides from unripe banana peel: Its anti-inflammatory and α-glucosidase inhibition properties

Banana peel represents a significant waste product of banana processing industries that can yield high-value products. Banana peel contains flavonols, tannins, alkaloids, terpenoids, and various phenolic compounds such as catechin, epicatechin, and catecholamines. Recent studies have demonstrated the immunomodulatory, anti-inflammatory, and antidiabetic potential of these compounds. The current work serves as the first report on the glucocerebroside (GC) consortium from the unripe banana peel Musa (AAB) cv. Nendran. Through high resolution mass spectrometry analysis, we have identified eighteen molecular species of GC, containing α- and ω‑hydroxy fatty acids. The in vitro anti-inflammation potential of GC consortium was assessed in RAW 264.7 murine macrophage cell line. The GC consortium at a dose of 50 μg/mL, showed a significant reduction in lipopolysaccharide (LPS)-induced nitric oxide (NO) production. The enzyme-linked immunosorbent assay (ELISA) analysis demonstrated GC's immunomodulation potential by showing a reduction in pro-inflammatory cytokines and increase in anti-inflammatory cytokine production. Furthermore, GC exhibited potent α-glucosidase inhibition with an IC50 value of 5.12 ± 0.51 μg/mL, significantly lower than standard acarbose (IC50 = 87.32 ± 1.99 μg/mL). This research highlights the potential of GC as a promising candidate for therapeutic application due to its anti-inflammatory and α-glucosidase inhibition properties.

Improved analysis of grape seed extract by liquid chromatography–high resolution mass spectrometry (LC-HRMS) reveals that proanthocyanidin-protein interaction mechanisms in cream depend on degree of polymerization

This study aimed to comprehensively characterize chemical profiles of proanthocyanidins (PACs) from grape seed extract (GSE), examine their interactions with proteins in a cream system, and define the mechanisms mediating PAC-protein interactions. GSE PACs were fractionated and characterized by thiolysis followed by liquid chromatography–high resolution mass spectrometry (LC-HRMS) analysis. New PACs with a degree of polymerization (DP) up to 16 were identified by improved HRMS data processing methods. In the model cream system, high-DP PACs exhibited greater precipitation capacity and protein binding than low-DP PACs. Low-DP PACs primarily engaged in hydrogen bonding, while high-DP PACs predominantly utilized multiple hydrophobic interaction sites to form cream protein aggregates. Furthermore, particle size and viscosity measurement of cream revealed a progressively DP-dependent increase in aggregated fat globules and cream viscosity. These findings enhanced our understanding of PACs’ structural intricacies and highlighted their functional role as PAC-rich natural ingredients in creating structured cream systems.

Tracing the biographies of textiles in the transition of medieval to modern times: Wool fabrics and brigandines from an Iberian castle

Findings of archaeological textiles and fibres in Northern Iberia are extremely rare. The occurrence of a set of textile fragments, dated between the 14th and 16th centuries CE at the Pambre castle (Palas de Rei, Lugo, Spain) is exceptional. The original stone roof of the southeastern tower was intact. The dark, cold and moist conditions inside the tower favoured the preservation of a unique series of waterlogged textile remains. In addition, a set of pseudomorphs preserved by mineral replacement were recovered from the east edge of the north wing in the main hall of the castle. Fibres have been identified using optical and scanning electron microscopy (SEM), and they have been chemically characterised using Energy Dispersive X-Ray Spectroscopy (EDX). We also performed analytical pyrolysis-GC-MS (Py-GC-MS) and thermally assisted hydrolysis and methylation (THM-GC-MS) of the wool fabrics and pseudomorphs to assess their state of degradation and the presence of chemical markers associated to the use of these textile remains. High performance liquid chromatography with diode array detection (HPLC-DAD-MS) and ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS) analysis were applied on wool fabrics to identify the chemical markers of dyes but without success. To expand the information related to raw material identification and the technical aspects of the fabrics, further evidence such as adherences identified as opal phytoliths, seeds, and insect remains associated to wool fabrics were examined. These findings offer a unique glimpse into the clothing dated to the end of the Medieval period, and its life-cycle. Wool scraps were probably part of at least two different garments, whereas the mineralised textiles probably formed part of at least two brigandines which were made of bast fibres, flax, or hemp.

Marine benthic diatom Psammodictyon panduriforme (MACC 35) as a potent producer of long chain hydrocarbons and fatty acids of biofuel significance

Marine diatoms are promising feedstock for biofuel industries as a source of hydrocarbons and fatty acids. In the present study, eleven marine diatom isolates from the west coast of India were analysed for hydrocarbons and lipids. The comparative analyses indicated that Psammodictyon panduriforme (MACC 35), a diatom isolate from the water samples collected from 1000 m depth, with a hydrocarbon yield of 37.27 mg g−1 L−1 and 2.1 % of the total biomass of 0.56 gL−1 was a promising species followed by Biddulphia sp. (MACC 6) with hydrocarbon yield of 25.4 mg g−1 L−1 and 1.3 % of the total biomass of 0.48 g L−1. Hydrocarbon analyses by gas chromatography with high resolution mass spectrometry (GCMS) showed that the long chain hydrocarbons found in the majority of the marine diatoms were undecane 4,7 dimethyl, hexadecane, octadecane,3-ethyl-5-(2-ethyl-butyl), tetradecane, tetracosane, eicosane-2 methyl, heptacosaneand hexacosane. The fatty acid profile showed the presence of stearic acid, 9-octadecenoic acid, myristic acid, palmitic acid, and arachidic acid with excellent biodiesel properties. Hydrocarbons of high fuel quality can be produced by optimizing hydrocarbon production in the potent marine diatom Psammodictyon panduriforme and catalytic cracking of long chain hydrocarbons to short chain alkanes with high octane ratings.

Syntheses and reactivities of polymethylated ferrocenes: The effect of methylation upon electrophilic addition

A series of ferrocene derivatives with three, four, five, six and seven methyl group substituents has been prepared and characterized by multinuclear NMR, high resolution mass spectrometry and elemental analyses. Chemical oxidation of heptamethylferrocene with silver tetrafluoroborate produced paramagnetic heptamethylferricenium tetrafluorborate and the structure of one isomer of [C5Me4HFeC5Me3H2][BF4] was determined by single crystal X-ray diffraction. Electrochemical studies of the entire series of iron sandwich compounds from ferrocene to decamethylferrocene reveal a highly linear shift of the reversible half-wave potential (E1/2) for the FeIII/FeII couple such that each additional methyl group lowers E1/2 by an average of 54 mV. A new triple-decker complex has been synthesized by the addition of a ruthenium electrophile, [Cp*Ru(NCMe)3][PF6], (Cp* = C5Me5) to heptamethylferrocene, Me7FcH. While previous work established that reactions between [Cp*Ru(NCMe)3][PF6] and ferrocene derivatives with eight or more methyl group substituents readily form bimetallic complexes, reactions with ferrocene derivatives with six or fewer methyl groups brought about ring abstraction and afforded only monometallic products. Thus it may be concluded that there is a “tipping point” in the series of polymethylated ferrocenes such that the electron donating ability and/or steric influence of seven methyl groups is just sufficient to stabilize a ruthenium-iron tripledecker complex.

Innovative analytical methodologies for characterizing chemical exposure with a view to next-generation risk assessment

The chemical burden on the environment and human population is increasing. Consequently, regulatory risk assessment must keep pace to manage, reduce, and prevent adverse impacts on human and environmental health associated with hazardous chemicals. Surveillance of chemicals of known, emerging, or potential future concern, entering the environment-food-human continuum is needed to document the reality of risks posed by chemicals on ecosystem and human health from a one health perspective, feed into early warning systems and support public policies for exposure mitigation provisions and safe and sustainable by design strategies. The use of less-conventional sampling strategies and integration of full-scan, high-resolution mass spectrometry and effect-directed analysis in environmental and human monitoring programmes have the potential to enhance the screening and identification of a wider range of chemicals of known, emerging or potential future concern. Here, we outline the key needs and recommendations identified within the European Partnership for Assessment of Risks from Chemicals (PARC) project for leveraging these innovative methodologies to support the development of next-generation chemical risk assessment.

Perturbations in human bile acid profiles following drug-induced liver injury investigated using semitargeted high-resolution mass spectrometry.

Acetaminophen (APAP) overdose is the leading cause of acute liver failure (ALF) in North America. To investigate the effect of drug-induced liver injury (DILI) on circulating bile acid (BA) profiles, serum from ALF patients and healthy controls were analyzed using a semitargeted high-resolution mass spectrometry approach to measure BAs in their unconjugated and amidated forms and their glucuronide and sulfate conjugates. Human serum samples from 20 healthy volunteers and 34 ALF patients were combined with deuterated BAs and extracted, prior to liquid chromatography high-resolution tandem mass spectrometry analysis. A mix of 46 standards helped assign 26 BAs in human serum by accurate mass and retention time matching. Moreover, other isomers of unconjugated and amidated BAs, as well as glucuronide and sulfate conjugates, were assigned by accurate mass filtering. In vitro incubations of standard BAs provided increased information for certain peaks of interest. A total of 275 BA metabolites, with confirmed or putative assignments, were measured in human serum samples. APAP overdose significantly influenced the levels of most BAs, promoting glycine conjugation, and, to a lesser extent, taurine conjugation. When patient outcome was considered, 11 BAs were altered significantly, including multiple sulfated species. Although many of the BAs measured did not have exact structures assigned, several putatively identified BAs of interest were further characterized using in vitro incubations. An optimized chromatographic separation tailored to BAs of ranging polarities was combined with accurate mass measurements to investigate the effect that DILI has on their complex profiles and metabolism to a much wider extent than previously possible. The analysis of complex BA profiles enabled in-depth analysis of the BA metabolism perturbations in ALF, including certain metabolites related to patient outcomes.

The Interaction between Human Microbes and Advanced Glycation End Products: The Role of Klebsiella X15 on Advanced Glycation End Products' Degradation.

Previous studies have shown that advanced glycation end products (AGEs) are implicated in the occurrence and progression of numerous diseases, with dietary AGEs being particularly associated with intestinal disorders. In this study, methylglyoxal-beta-lactoglobulin AGEs (MGO-β-LG AGEs) were utilized as the exclusive nitrogen source to investigate the interaction between protein-bound AGEs and human gut microbiota. The high-resolution mass spectrometry analysis of alterations in peptides containing AGEs within metabolites before and after fermentation elucidated the capacity of intestinal microorganisms to enzymatically hydrolyze long-chain AGEs into short-chain counterparts. The 16S rRNA sequencing revealed Klebsiella, Lactobacillus, Escherichia-Shigella, and other genera as dominant microbiota at different fermentation times. A total of 187 potential strains of AGE-metabolizing bacteria were isolated from the fermentation broth at various time points. Notably, one strain of Klebsiella exhibited the most robust growth capacity when AGEs served as the sole nitrogen source. Subsequently, proteomics was employed to compare the changes in protein levels of Klebsiella X15 following cultivation in unmodified proteins and proteins modified with AGEs. This analysis unveiled a remodeled amino acid and energy metabolism pathway in Klebsiella in response to AGEs, indicating that Klebsiella may possess a metabolic pathway specifically tailored to AGEs. This study found that fermenting AGEs in healthy human intestinal microbiota altered the bacterial microbiota structure, especially by increasing Klebsiella proliferation, which could be a key factor in AGEs' role in causing diseases, particularly intestinal inflammation.

Workflow to facilitate the detection of new psychoactive substances and drugs of abuse in influent urban wastewater

The complexity around the dynamic markets for new psychoactive substances (NPS) forces researchers to develop and apply innovative analytical strategies to detect and identify them in influent urban wastewater. In this work a comprehensive suspect screening workflow following liquid chromatography – high resolution mass spectrometry analysis was established utilising the open-source InSpectra data processing platform and the HighResNPS library. In total, 278 urban influent wastewater samples from 47 sites in 16 countries were collected to investigate the presence of NPS and other drugs of abuse. A total of 50 compounds were detected in samples from at least one site. Most compounds found were prescription drugs such as gabapentin (detection frequency 79%), codeine (40%) and pregabalin (15%). However, cocaine was the most found illicit drug (83%), in all countries where samples were collected apart from the Republic of Korea and China. Eight NPS were also identified with this protocol: 3-methylmethcathinone 11%), eutylone (6%), etizolam (2%), 3-chloromethcathinone (4%), mitragynine (6%), phenibut (2%), 25I-NBOH (2%) and trimethoxyamphetamine (2%). The latter three have not previously been reported in municipal wastewater samples. The workflow employed allowed the prioritisation of features to be further investigated, reducing processing time and gaining in confidence in their identification.

Design, Synthesis, and Characterization of Organometallic BODIPY-Ru(II) Dyads: Redox and Photophysical Properties with Singlet Oxygen Generation Capability†.

A series of Ru(II)-acetylide complexes (Ru1, Ru2, and Ru1m) with alkynyl-functionalized borondipyrromethene (BODIPY) conjugates were designed by varying the position of the linker that connects the BODIPY unit to the Ru(II) metal center through acetylide linkage at either the 2-(Ru1) and 2,6-(Ru2) or the meso-phenyl (Ru1m) position of the BODIPY scaffold. The Ru(II) organometallic complexes were characterized by various spectroscopic methods, including nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, CHN, and high-resolution mass spectrometry (HRMS) analyses. The Ru(II)-BODIPY conjugates exhibit fascinating electrochemical and photophysical properties. All BODIPY-Ru(II) complexes exhibit strong absorption (εmax = 29,000-72,000 M-1 cm-1) in the visible region (λmax = 502-709 nm). Fluorescence is almost quenched for Ru1 and Ru2, whereas Ru1m shows the residual fluorescence of the corresponding BODIPY core at 517 nm. The application of the BODIPY-Ru(II) dyads as nonporphyrin-based triplet photosensitizers was explored by a method involving the singlet oxygen (1O2)-mediated photo-oxidation of diphenylisobenzofuran. Effective π-conjugation between the BODIPY chromophore and Ru(II) center in the case of Ru1 and Ru2 was found to be necessary to improve intersystem crossing (ISC) and hence the 1O2-sensitizing ability. In addition, electrochemical studies indicate electronic interplay between the metal center and the redox-active BODIPY in the BODIPY-Ru(II) dyads.

Identification and nitric oxide production inhibitory activity of phenolic derivatives from the trunks of Gnetum latifolium

Phytochemical investigation of the trunks from Gnetum latifolium led to the isolation of a novel phenolic glucoside, 2E-2,4-di-(3,4-dihydroxyphenyl)but-2-en-1-yl-O-β-D-glucopyranoside (1), along with five known stilbene derivatives (2–6). Their structures were determined mainly using high-resolution electrospray ionisation mass spectrometry and nuclear magnetic resonance spectroscopic analyses, followed by comparisons of observed spectral data with reported values. The novel compound 1 in G. latifolium was found to be useful as a chemotaxonomic marker. Biological evaluation revealed that compound 6 had remarkable inhibitory effects on nitric oxide production, with a half-maximal inhibitory concentration (IC50) value of 4.85 ± 0.20 µM, which was much higher than that of the positive control dexamethasone (IC50 = 14.20 ± 0.54 µM).

Optimization, Metabolomic Analysis, Antioxidant Potential andDepigmenting Activity of Polyphenolic Compounds fromUnmature Ajwa Date Seeds (Phoenix dactylifera L.) Using Ultrasonic-Assisted Extraction.

This study sought to optimize the ultrasonic-assisted extraction of polyphenolic compounds from unmature Ajwa date seeds (UMS), conduct untargeted metabolite identification and assess antioxidant and depigmenting activities. Response surface methodology (RSM) utilizing the Box-Behnken design (BBD) and artificial neural network (ANN) modeling was applied to optimize extraction conditions, including the ethanol concentration, extraction temperature and time. The determined optimal conditions comprised the ethanol concentration (62.00%), extraction time (29.00 min), and extraction temperature (50 °C). Under these conditions, UMS exhibited total phenolic content (TPC) and total flavonoid content (TFC) values of 77.52 ± 1.55 mgGAE/g and 58.85 ± 1.12 mgCE/g, respectively, with low relative standard deviation (RSD%) and relative standard error (RSE%). High-resolution mass spectrometry analysis unveiled the presence of 104 secondary metabolites in UMS, encompassing phenols, flavonoids, sesquiterpenoids, lignans and fatty acids. Furthermore, UMS demonstrated robust antioxidant activities in various cell-free antioxidant assays, implicating engagement in both hydrogen atom transfer and single electron transfer mechanisms. Additionally, UMS effectively mitigated tert-butyl hydroperoxide (t-BHP)-induced cellular reactive oxygen species (ROS) generation in a concentration-dependent manner. Crucially, UMS showcased the ability to activate mitogen-activated protein kinases (MAPKs) and suppress key proteins including tyrosinase (Tyr), tyrosinase-related protein-1 and -2 (Trp-1 and -2) and microphthalmia-associated transcription factor (MITF), which associated melanin production in MNT-1 cell. In summary, this study not only optimized the extraction process for polyphenolic compounds from UMS but also elucidated its diverse secondary metabolite profile. The observed antioxidant and depigmenting activities underscore the promising applications of UMS in skincare formulations and pharmaceutical developments.

Characterization of Hair Metabolome in 5xFAD Mice and Patients with Alzheimer's Disease Using Mass Spectrometry-Based Metabolomics.

Hair emerged as a biospecimen for long-term investigation of endogenous metabolic perturbations, reflecting the chemical composition circulating in the blood over the past months. Despite its potential, the use of human hair for metabolomics in Alzheimer's disease (AD) research remains limited. Here, we performed both untargeted and targeted metabolomic approaches to profile the key metabolic pathways in the hair of 5xFAD mice, a widely used AD mouse model. Furthermore, we applied the discovered metabolites to human subjects. Hair samples were collected from 6-month-old 5xFAD mice, a stage marked by widespread accumulation of amyloid plaques in the brain, followed by sample preparation and high-resolution mass spectrometry analysis. Forty-five discriminatory metabolites were discovered in the hair of 6-month-old 5xFAD mice compared to wild-type control mice. Enrichment analysis revealed three key metabolic pathways: arachidonic acid metabolism, sphingolipid metabolism, and alanine, aspartate, and glutamate metabolism. Among these pathways, six metabolites demonstrated significant differences in the hair of 2-month-old 5xFAD mice, a stage prior to the onset of amyloid plaque deposition. These findings suggest their potential involvement in the early stages of AD pathogenesis. When evaluating 45 discriminatory metabolites for distinguishing patients with AD from nondemented controls, a combination of l-valine and arachidonic acid significantly differentiated these two groups, achieving a 0.88 area under the curve. Taken together, these findings highlight the potential of hair metabolomics in identifying disease-specific metabolic alterations and developing biomarkers for improving disease detection and monitoring.

Novel Flurbiprofen Derivatives as Antioxidant and Anti-Inflammatory Agents: Synthesis, In Silico, and In Vitro Biological Evaluation.

In this study, we present the synthesis of five novel compounds by combining flurbiprofen with various substituted 2-phenethylamines. The synthesized derivatives underwent comprehensive characterization using techniques such as 1H- and 13C-NMR spectroscopy, UV-Vis spectroscopy, and high-resolution mass spectrometry (HRMS). Detailed HRMS analysis was performed for each of these newly created molecules. The biological activities of these compounds were assessed through in vitro experiments to evaluate their potential as anti-inflammatory and antioxidant agents. Furthermore, the lipophilicity of these derivatives was determined, both theoretically using the cLogP method and experimentally through partition coefficient (RM) measurements. To gain insights into their binding affinity, we conducted an in silico analysis of the compounds' interactions with human serum albumin (HSA) using molecular docking studies. Our findings reveal that all of the newly synthesized compounds exhibit significant anti-inflammatory and antioxidant activities, with results statistically comparable to the reference compounds. Molecular docking studies further explain the observed in vitro results, shedding light on the molecular mechanisms behind their biological activities. Using in silico method, toxicity was calculated, resulting in LD50 values. Depending on the administration route, the novel flurbiprofen derivatives show lower toxicity compared to the standard flurbiprofen.