High-resolution Mass Spectrometry Research Articles

High-Resolution Mass Spectrometry for Human Exposomics: Expanding Chemical Space Coverage.

In the modern "omics" era, measurement of the human exposome is a critical missing link between genetic drivers and disease outcomes. High-resolution mass spectrometry (HRMS), routinely used in proteomics and metabolomics, has emerged as a leading technology to broadly profile chemical exposure agents and related biomolecules for accurate mass measurement, high sensitivity, rapid data acquisition, and increased resolution of chemical space. Non-targeted approaches are increasingly accessible, supporting a shift from conventional hypothesis-driven, quantitation-centric targeted analyses toward data-driven, hypothesis-generating chemical exposome-wide profiling. However, HRMS-based exposomics encounters unique challenges. New analytical and computational infrastructures are needed to expand the analysis coverage through streamlined, scalable, and harmonized workflows and data pipelines that permit longitudinal chemical exposome tracking, retrospective validation, and multi-omics integration for meaningful health-oriented inferences. In this article, we survey the literature on state-of-the-art HRMS-based technologies, review current analytical workflows and informatic pipelines, and provide an up-to-date reference on exposomic approaches for chemists, toxicologists, epidemiologists, care providers, and stakeholders in health sciences and medicine. We propose efforts to benchmark fit-for-purpose platforms for expanding coverage of chemical space, including gas/liquid chromatography-HRMS (GC-HRMS and LC-HRMS), and discuss opportunities, challenges, and strategies to advance the burgeoning field of the exposome.

Escuzarmycins A-D, Potent Biofungicides to Control Septoria tritici Blotch.

A study targeting novel antifungal metabolites identified potent in vitro antifungal activity against key plant pathogens in acetone extracts of Streptomyces sp. strain CA-296093. Feature-based molecular networking revealed the presence in this extract of antimycin-related compounds, leading to the isolation of four new compounds: escuzarmycins A-D (1-4). Extensive structural elucidation, employing 1D and 2D NMR, high-resolution mass spectrometry, Marfey's analysis, and NOESY correlations, confirmed their structures. The bioactivity of these compounds was tested against six fungal phytopathogens, and compounds 3 and 4 demonstrated strong efficacy, particularly against Zymoseptoria tritici, with compound 3 exhibiting the highest potency (EC50: 11 nM). Both compounds also displayed significant antifungal activity against Botrytis cinerea and Colletotrichum acutatum, with compound 4 proving to be the most potent. Despite moderate cytotoxicity against the human cancer cell line HepG2, compounds 3 and 4 emerge as promising fungicides for combating Septoria tritici blotch, anthracnose, and gray mold.

Selective Profiling of Carboxylic Acid in Crude Oil by Halogen Labeling Combined with Liquid Chromatography and High-Resolution Mass Spectrometry.

Carboxylic acids are a small but essential compound class within petroleum chemistry, influencing crude oil behaviors in production and processing and causing environmental impacts. Detailed structural information is fundamental to understanding their influence on petroleum characteristics. However, characterizing acids in crude oil remains challenging due to matrix effects, structural diversity, and low abundance. In this work, we present a new methodology for profiling carboxylic acids by liquid-liquid extraction and selective derivatization using 4-bromo-N-methylbenzylamine (4-BNMA) followed by liquid chromatography and electrospray ionization Orbitrap mass spectrometry (LC-ESI-Orbitrap MS). The fragmentation of 4-BNMA derivatives produces a unique product ion pair, m/z 169/171, enabling the identification of chromatographic fractions containing carboxylic acids. The mass spectra of the corresponding fractions are extracted, and the acids are further computationally isolated based on the isotopic pattern. The method was optimized and validated using acid standards and systematic experimental designs, assuring robustness and sensitivity for nontarget screening purposes. This method detected up to 380 carboxylic acids in six Danish North Sea crude oils, with up to two carboxyl and other heteroatom functionalities (NSO). The results indicated that the most populated species are fatty acids (double bond equivalent (DBE) = 1) and small aromatic acids (DBE = 2-6). The predominance and diversities of compound classes in different samples are consistent with their corresponding bulk properties. Polyfunctional acids (Ox, NxOx, and SxOx) were observed due to exposure to oxidation and biodegradation. Also, the approach's applicability benefits high-resolution MS analysis by simplifying data processing for crude oil and potentially other high-organic and aqueous samples.

ICP-MS As a Contributing Tool to Nontarget Screening (NTS) Analysis for Environmental Monitoring.

Due to the increasing number of chemicals released into the environment, nontarget screening (NTS) analysis is a necessary tool for providing comprehensive chemical analysis of environmental pollutants. However, NTS workflows encounter challenges in detecting both known and unknown pollutants with common chromatography high-resolution mass spectrometry (HRMS) methods. Identification of unknowns is hindered by limited elemental composition information, and quantification without identical reference standards is prone to errors. To address these issues, we propose the use of inductively coupled plasma mass spectrometry (ICP-MS) as an element-specific detector. ICP-MS can enhance the confidence of compound identification and improve quantification in NTS due to its element-specific response and unambiguous chemical composition information. Additionally, mass balance calculations for individual elements (F, Br, Cl, etc.) enable assessment of total recovery of those elements and evaluation of NTS workflows. Despite its benefits, implementing ICP-MS in NTS analysis and environmental regulation requires overcoming certain shortcomings and challenges, which are discussed herein.

Steroid Profiling and Circadian Cortisol Secretion in Patients with Mild Autonomous Cortisol Secretion: A Cross-Sectional Study.

Mild autonomous cortisol secretion (MACS) is diagnosed based on post-dexamethasone cortisol>1.8 mcg/dL. Scarce evidence exists on steroid circadian secretion and steroid metabolome in MACS. To characterize 24-hour (h) urine steroid metabolome in patients with MACS and determine circadian differences in urine steroid profiling and cortisol concentrations in patients with MACS versus referent subjects. Cross-sectional study, 2018-2023. Referral center. Patients with MACS and age-, sex-, BMI-, and menopausal status-matched referent subjects. Urine was collected over 24h period as separate day- and night-time collections. High-resolution mass spectrometry assay was used to measure 25 steroids. A subgroup of patients and referent subjects were admitted for every 2h serum measurements of free and total cortisol. Steroids, sums, and ratios. Patients with MACS (n=72) had lower mcg/24h median androgens (2084 vs 3283, P<0.001), higher glucocorticoids (15754 vs 12936, P<0.001), and higher glucocorticoid/androgen ratio (8.7 vs 3.9, P<0.001), compared to referent subjects. Patients also had lower steroid day/night ratios compared to referent subjects, reflecting a higher relative nocturnal steroid production in MACS. In a subgroup of 12 patients with MACS and 10 referent subjects, the 24-hour area under the curves for total and free cortisol were similar. However, evening mean total (5.3 vs 4.0 mcg/dL, P=0.056) and free (0.2 vs 0.1 mcg/dL, P=0.035) cortisol was higher in patients vs referent subjects. Patients with MACS demonstrate an abnormal urine steroid metabolome, with a high glucocorticoid to androgen ratio, and a higher nocturnal steroid production.

Preferential Partitioning of Per- and Polyfluoroalkyl Substances (PFAS) and Dissolved Organic Matter in Freshwater Surface Microlayer and Natural Foam.

Per- and polyfluoroalkyl substances (PFAS) are surfactants that can accumulate in the surface microlayer (SML) and in natural foams, with potential elevated exposure for organisms at the water surface. However, the impact of water chemistry on PFAS accumulation in these matrices in freshwater systems is unknown. We quantified 36 PFAS in water, the SML, and natural foams from 43 rivers and lakes in Wisconsin, USA, alongside measurements of pH, cations, and dissolved organic carbon (DOC). PFAS partition to foams with concentration ranging 2300-328,200 ng/L in waters with 6-139 ng/L PFAS (sum of 36 analytes), corresponding to sodium-normalized enrichment factors ranging <50 to >7000. Similar enrichment is observed for DOC (∼70). PFAS partitioning to foams increases with increasing chain length and is positively correlated with [DOC]. Modest SML enrichment is observed for PFOS (1.4) and FOSA (2.4), while negligible enrichment is observed for other PFAS and DOC due to low specific surface area and turbulent conditions that inhibit surfactant accumulation. However, DOC composition in the SML is distinct from bulk water, as assessed using high-resolution mass spectrometry. This study demonstrates that natural foams in unimpacted and impacted waters can have elevated PFAS concentrations, whereas SML accumulation in surface waters is limited.

Characterization of the Polyphenolic Profile in Tomato (Lycopersicon esculentum P. Mill) Peel and Seeds by LC-HRMS/MS.

Peel and seeds are the main byproducts from tomato (Lycopersicon esculentum P. Mill) processing with high concentrations of polyphenols that have been underexploited. Herein, polyphenolic profiles in tomato peel and seeds were elucidated by untargeted liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) with an LTQ Orbitrap analyzer. Samples from two Spanish regions─"Murcia" and "Almería"─were analyzed to obtain complementary results. 57 compounds were found, mainly phenolic acids and flavonoids, of which eight were identified for the first time in tomato. Polyphenols were more abundant in byproducts from "Murcia" samples than in those from"Almería" samples, where the abundance of compounds like coutaric, caffeic, neochlorogenic, dicaffeoylquinic and ferulic acids, vanillic acid hexoside, catechin, naringenin, prunin, apigenin-O-hexoside, rutin, and rutin-O-pentoside was even much higher in byproducts than that in whole fruits. These results reveal the wide range of polyphenols found in tomato byproducts, with potential applications in pharmaceutical research, food preservation, and cosmetic development, among others.

Small and Large Extracellular Vesicles of Porcine Seminal Plasma Differ in Lipid Profile

Seminal plasma contains a heterogeneous population of extracellular vesicles (sEVs) that remains poorly characterized. This study aimed to characterize the lipidomic profile of two subsets of differently sized sEVs, small (S-) and large (L-), isolated from porcine seminal plasma by size-exclusion chromatography and characterized by an orthogonal approach. High-performance liquid chromatography–high-resolution mass spectrometry was used for lipidomic analysis. A total of 157 lipid species from 14 lipid classes of 4 major categories (sphingolipids, glycerophospholipids, glycerolipids, and sterols) were identified. Qualitative differences were limited to two cholesteryl ester species present only in S-sEVs. L-sEVs had higher levels of all quantified lipid classes due to their larger membrane surface area. The distribution pattern was different, especially for sphingomyelins (more in S-sEVs) and ceramides (more in L-sEVs). In conclusion, this study reveals differences in the lipidomic profile of two subsets of porcine sEVs, suggesting that they differ in biogenesis and functionality.

Profiling of Organosulfur Compounds in Onions: A Comparative Study between LC-HRMS and DTD-GC-MS

Onions are known not only for their culinary importance but also for their nutritional and health-promoting properties. Both properties are closely linked to their content of organosulfur compounds, which account for up to 5% of the dry weight of an onion. Given the importance of these compounds, suitable analytical methods are required for their study. Two techniques should be highlighted in this context: gas chromatography coupled to mass spectrometry (GC-MS), and liquid chromatography coupled to mass spectrometry (LC-MS). In this study, eight different onion varieties were analyzed using two distinct analytical techniques: direct thermal desorption–gas chromatography–mass spectrometry (DTD-GC-MS) and high-resolution mass spectrometry (HRMS) on an LC-ESI-QqTOF instrument. Each method identified different organosulfur compounds, with LC-HRMS targeting 15 non-volatile compounds, such as cysteine sulfoxides, and GC-MS targeting 18 volatiles, such as disulfides and trisulfides. The results obtained were studied using Pearson correlations and principal component analysis. No precise correlation was found between the initial organosulfur compounds in onions and their hydrolysates. Consequently, although GC is one of the most employed techniques in the scientific literature, the use of LC-HRMS or a combination of both techniques may offer a more comprehensive and accurate description of the metabolomic profile of onions.

Metabolic and Lipid Biomarkers for Pathogenic Algae, Fungi, Cyanobacteria, Mycobacteria, Gram-Positive Bacteria, and Gram-Negative Bacteria

The utilization of metabolomics and lipidomics analytical platforms in the study of pathogenic microbes is slowly expanding. These research approaches will significantly contribute to the establishment of microbial metabolite and lipid databases of significant value to all researchers in microbiology. In this review, we present a high-level overview of some examples of biomarkers that can be used to detect the presence of microbes, monitor the expansion/decline of a microbe population, and add to our understanding of microbe biofilms and pathogenicity. In addition, increased knowledge of the metabolic functions of pathogenic microbes can contribute to our understanding of microbes that are utilized in diverse industrial applications. Our review focuses on lipids, secondary metabolites, and non-ribosomal peptides that can be monitored using electrospray ionization high-resolution mass spectrometry (ESI-HRMS).

A comparative metabolomics analysis of Açaí (Euterpe oleracea Mart.) fruit, food powder, and botanical dietary supplement extracts.

Euterpe oleracea Mart. (açaí) is a botanical of interest to many who seek functional foods that provide antioxidant and anti-inflammatory properties. Cancer patients are increasingly taking botanical dietary supplements containing açaí to complement their conventional therapeutics, which may lead to serious adverse events. Before testing our açaí extracts in vitro for botanical-drug interactions, the goal is to chemically characterize our extracts for compounds whose biological activity in açaí is unknown. The objective of this work was to develop a chemical fingerprinting method for untargeted characterization of açaí samples from a variety of sources, including food products and botanical dietary supplement capsules, made with multiple extraction solvents. An optimized LC-MS method was generated for in-depth untargeted fingerprinting of chemical constituents in açaí extracts. Statistical analysis models were used to describe relationships between the açaí extracts based on molecular features found in both positive and negative mode ESI. In an attempt to elucidate the differences in metabolites among açaí extracts from different cultivars, we identified or tentatively identified 173 metabolites from the 16 extracts made from 6 different sources. Of these compounds, there are 138 reported in açaí for the first time. Statistical models showed similar yet distinct differences between the extracts tested based on the polarity of compounds present and the origin of the source material. A high-resolution mass spectrometry method was generated that allowed us to greatly characterize 16 complex extracts made from different sources of açaí with different extraction solvent polarities.

Enhancing Molecular Characterization of Dissolved Organic Matter by Integrative Direct Infusion and Liquid Chromatography Nontargeted Workflows.

Dissolved organic matter (DOM) in aquatic systems is a highly heterogeneous mixture of water-soluble organic compounds, acting as a major carbon reservoir driving biogeochemical cycles. Understanding DOM molecular composition is thus of vital interest for the health assessment of aquatic ecosystems, yet its characterization poses challenges due to its complex and dynamic chemical profile. Here, we performed a comprehensive chemical analysis of DOM from highly urbanized river and seawater sources and compared it to drinking water. Extensive analyses by nontargeted direct infusion (DI) and liquid chromatography (LC) high-resolution mass spectrometry (HRMS) through Orbitrap were integrated with novel computational workflows to allow molecular- and structural-level characterization of DOM. Across all water samples, over 7000 molecular formulas were calculated using both methods (∼4200 in DI and ∼3600 in LC). While the DI approach was limited to molecular formula calculation, the downstream data processing of MS2 spectral information combining library matching and in silico predictions enabled a comprehensive structural-level characterization of 16% of the molecular space detected by LC-HRMS across all water samples. Both analytical methods proved complementary, covering a broad chemical space that includes more highly polar compounds with DI and more less polar ones with LC. The innovative integration of diverse analytical techniques and computational workflow introduces a robust and largely available framework in the field, providing a widely applicable approach that significantly contributes to understanding the complex molecular composition of DOM.

A Diterpenoid of the Medicinal Plant Andrographis paniculata Targets Cutaneous TRPV3 Channel and Relieves Itch.

Transient receptor potential vanilloid subtype 3 (TRPV3) is an ion channel implicated in skin physiology and itch. TRPV3 inhibitors can present a novel strategy for combating debilitating itch conditions, and medicinal plants are a natural pool of such compounds. Here, we report the isolation of a TRPV3-inhibiting compound from Andrographis paniculata, a medicinal plant with anti-inflammatory properties whose bioactive components are poorly characterized in terms of molecular targets. Using 1H and 13C NMR and high-resolution mass spectrometry, the compound was identified as a labdane-type diterpenoid, 14-deoxy-11,12-didehydroandrographolide (ddA). The activity of the compound was evaluated by fluorescent calcium assay and manual whole-cell patch-clamp technique. ddA inhibited human TRPV3 in stably expressing CHO and HaCaT keratinocytes, acting selectively among other TRP channels implicated in itch and inflammation and not showing toxicity to HaCaT cells. Antipruritic effects of the compound were evaluated in scratching behavior models on ICR mice. ddA suppressed itch induced by the TRPV3 activator carvacrol. Additionally, ddA potently suppressed histamine-induced itch with efficacy comparable to loratadine, a clinically used antihistamine drug. These results suggest the potential of ddA as a possible safe and efficacious alternative for antipruritic therapy.

The Antiaromatic Nucleophilic Substitution Reaction (SNAAr) in Cycloheptatrienyl-Anion Containing Zwitterions with a Möbius-Aromatic Intermediate.

Antiaromatic nucleophilic substitution reactions in cycloheptatrienide pyridinium and phosphonium zwitterions with initial formation of a cycloheptatetraene intermediate are explored. The mechanism was supported by quantum chemical calculations, first-order reaction kinetics, and high-resolution mass spectrometry. The pyridinium zwitterion exhibited weak antiaromaticity, whereas the intermediate displayed Möbius aromaticity, as evidenced by nuclear independent chemical shift values and the shape of its HOMO. This study represents the eighth confirmed instance of a Möbius-aromatic organic species in its ground state.

Deciphering Transcriptomic and Metabolomic Wood Responses to Grapevine Trunk Disease-Associated Fungi

Esca is one of the main grapevine trunk diseases affecting vineyards worldwide. Phaeoacremonium minimum and Phaeomoniella chlamydospora are thought to be two of the main causal agents of this disease. However, the molecular mechanisms underlying plant defense responses in the grapevine trunk against esca-associated pathogens are poorly understood. To provide a first glimpse at the trunk responses to P. minimum and P. chlamydospora, transcriptomic and metabolomic analyses were performed to compare and contrast host responses to these pathogens. Transcriptomic analysis revealed different gene expression reprogramming in the trunk in response to each fungus. The main significant differences were found among genes associated with secondary metabolism, signaling, and hormone signaling. An untargeted liquid chromatography–high resolution mass spectrometry metabolomic approach performed 3 weeks after inoculation was used, and dereplication mainly highlighted flavonoids and stilbenes as plant defense metabolites in the infected trunk. Some metabolites were overproduced with both fungi, but specific responses were also observed. Particularly, a lipophilic flavonoid cluster was emphasized after P. minimum inoculation. The assessment of fungal infection 6 weeks postinfection showed more copies of P. minimum than P. chlamydospora. This dissimilarity in the level of colonization could be linked to the metabolomic responses observed. Our results reveal both different gene expression reprogramming and metabolomic-specific signatures depending on the wood pathogen. Altogether, these observations suggest that grapevine trunks can differently perceive and respond to P. minimum and P. chlamydospora. [Formula: see text] Copyright © 2024 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .

Hydroponic Growth of [13C]-Labeled Tobacco for DNA Damage Studies in Cigarette Smokers.

Cigarette smoking is the acknowledged major cause of cancers of the lung and oral cavity and is an established important risk factor for multiple other cancers. DNA addition products (DNA adducts) caused by cigarette smoking are critical factors in its mechanism of carcinogenesis. However, most DNA adducts detected to date in humans cannot be specifically ascribed to smoking but rather have multiple exogenous and endogenous sources. In the study reported here, we prepared [13C]-labeled tobacco to address this problem. We report for the first time the successful growth from seeds to flowering under hydroponic conditions of highly [13C]-labeled tobacco in a controlled 13CO2 environment. The standard growth procedure with optimized conditions is described in detail. The [13C]-enrichment rate was assessed by quantifying nicotine and sugars and their [13C]-isotopologues in this tobacco using high-resolution mass spectrometry, reaching >94% in the tobacco leaves. The [13C]-labeled leaves after curing will be used to make cigarettes, allowing investigation of the specific contributions of tobacco smoke carcinogens to identified DNA adducts in smokers.

Synthesis of Silver Nanoparticles Using Extracts from Different Parts of the Paullinia cupana Kunth Plant: Characterization and In Vitro Antimicrobial Activity

The green synthesis of silver nanoparticles (AgNPs) can be developed using safe and environmentally friendly routes, can replace potentially toxic chemical methods, and can increase the scale of production. This study aimed to synthesize AgNPs from aqueous extracts of guarana (Paullinia cupana) leaves and flowers, collected in different seasons of the year, as a source of active biomolecules capable of reducing silver ions (Ag+) and promoting the stabilization of colloidal silver (Ag0). The plant aqueous extracts were characterized regarding their metabolic composition by liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-HRMS/MS), phenolic compound content, and antioxidant potential against free radicals. The synthesized AgNPs were characterized by UV/Vis spectrophotometry, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and scanning electron microscopy coupled to energy-dispersive X-ray spectrometry (EDX). The results demonstrated that the chemical characterization indicated the presence of secondary metabolites of many classes of compounds in the studied aqueous extracts studied, but alkaloids and flavonoids were predominant, which are widely recognized for their antioxidant capabilities. It was possible to notice subtle changes in the properties of the nanostructures depending on parameters such as seasonality and the part of the plant used, with the AgNPs showing surface plasmon resonance bands between 410 and 420 nm using the leaf extract and between 440 and 460 nm when prepared using the flower extract. Overall, the average hydrodynamic diameters of the AgNPs were similar among the samples (61.98 to 101.6 nm). Polydispersity index remained in the range of 0.2 to 0.4, indicating that colloidal stability did not change with storage time. Zeta potential was above −30 mV after one month of analysis, which is adequate for biological applications. TEM images showed AgNPs with diameters between 40.72 to 48.85 nm and particles of different morphologies. EDX indicated silver content by weight between 24.06 and 28.81%. The synthesized AgNPs exhibited antimicrobial efficacy against various pathogenic microorganisms of clinical and environmental interest, with MIC values between 2.12 and 21.25 µg/mL, which is close to those described for MBC values. Therefore, our results revealed the potential use of a native species of plant from Brazilian biodiversity combined with nanotechnology to produce antimicrobial agents.

Soil Metaproteomics for Microbial Community Profiling: Methodologies and Challenges.

Soil represents a complex and dynamic ecosystem, hosting a myriad of microorganisms that coexist and play vital roles in nutrient cycling and organic matter transformation. Among these microorganisms, bacteria and fungi are key members of the microbial community, profoundly influencing the fate of nitrogen, sulfur, and carbon in terrestrial environments. Understanding the intricacies of soil ecosystems and the biological processes orchestrated by microbial communities necessitates a deep dive into their composition and metabolic activities. The advent of next-generation sequencing and 'omics' techniques, such as metagenomics and metaproteomics, has revolutionized our understanding of microbial ecology and the functional dynamics of soil microbial communities. Metagenomics enables the identification of microbial community composition in soil, while metaproteomics sheds light on the current biological functions performed by these communities. However, metaproteomics presents several challenges, both technical and computational. Factors such as the presence of humic acids and variations in extraction methods can influence protein yield, while the absence of high-resolution mass spectrometry and comprehensive protein databases limits the depth of protein identification. Notwithstanding these limitations, metaproteomics remains a potent tool for unraveling the intricate biological processes and functions of soil microbial communities. In this review, we delve into the methodologies and challenges of metaproteomics in soil research, covering aspects such as protein extraction, identification, and bioinformatics analysis. Furthermore, we explore the applications of metaproteomics in soil bioremediation, highlighting its potential in addressing environmental challenges.

DART-HRMS reveals metabolic changes of whey through microparticulation and fermentations

Despite native whey (hereafter termed WHEY) being a watery by-product rich in high-value nutritional components, it poses environmental concerns. Recently, the techniques of thermal-mechanical microparticulation to produce microparticulated whey (MPW) and a further process to ferment MPW (FMPW) were suggested, in order to recycle whey into a protein concentrated soft dairy cream that acquires also fat mimicking functionality. Aiming at monitoring the effects of this recycling process on the products’ metabolic profiles, samples (n = 8) of WHEY, MPW and two sub-types of FMPW were analysed by combining direct analysis in real time coupled with high resolution mass spectrometry (DART-HRMS). The most informative ions were used to build a partial least squared discriminant analysis (PLS-DA) model to assess the biochemical compounds that characterize and differentiate WHEY from MPW and FMPW. The DART-HRMS fingerprints acquired in negative mode accurately differentiated samples throughout the steps of microparticulation and fermentation. Post-fermentation, greater relative abundances of lactic acid, glucosamine and histidyl-aspartic acid were detected in both subtypes of FMPW, which were moderately differentiated by DART-HRMS. Moreover, while WHEY and MPW contained high relative abundances of hydroxyglutaric and malic acids, the fermented derivates (FMPW) were characterised by elevated levels of volatile compounds (tetradecanal, hexadecene and tetradecene) and fermentative end-products (diethyltartrate and histidyl-aspartic acid). DART-HRMS successfully captured a pool of informative biomarkers useful to understand the chemical and metabolomic changes occurring in microparticulation and fermentation processes used to recycle whey. This analytical technique is an operative supporting step needed for comprehensive assessment of the nutritional and organoleptic properties of the proposed whey-based soft cream dairy food.

Water-induced reversible deformation materials: Synthesis and UV polymerization of sulfonic based polyacrylates

Reversible deformable materials driven by water or humidity have crucial applications in many areas. A novel sulfonic based cross-linked polyacrylates were prepared by simple UV emulsion copolymerization of functional sulfonic based acrylates with conventional acrylates and epoxy acrylate resins. The structure of sulfonic based acrylates was characterized by FT-ATR,1H-NMR, high-resolution mass spectrometry. The thermal properties, surface morphology and structure of the cured polymers were analyzed. The reversible deformation induced by water and humidity were explored. Based on analysis of surface morphology, XPS and etching experiments, a reasonable deformation mechanism is proposed that the hydrophilic groups migrate to the surface of the oil-in-water colloidal particle film due to the difference in polarity and show a gradient distribution, and hydration of hydrophilic groups results in water absorption and film expansion. Reversible deformation materials driven by water or humidity are of great significance in the field of research on smart material systems.