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"nuclear magnetic resonance spectrometry"
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Ecometabolomics for a Better Understanding of Plant Responses and Acclimation to Abiotic Factors Linked to Global Change
by
Klem, Karel
,
Walker, Tom W.N.
,
Peñuelas, Josep
in
flavonoids
,
free amino acids
,
gas chromatography-mass spectrometry (GC-MS)
2020
The number of ecometabolomic studies, which use metabolomic analyses to disentangle organisms’ metabolic responses and acclimation to a changing environment, has grown exponentially in recent years. Here, we review the results and conclusions of ecometabolomic studies on the impacts of four main drivers of global change (increasing frequencies of drought episodes, heat stress, increasing atmospheric carbon dioxide (CO2) concentrations and increasing nitrogen (N) loads) on plant metabolism. Ecometabolomic studies of drought effects confirmed findings of previous target studies, in which most changes in metabolism are characterized by increased concentrations of soluble sugars and carbohydrate derivatives and frequently also by elevated concentrations of free amino acids. Secondary metabolites, especially flavonoids and terpenes, also commonly exhibited increased concentrations when drought intensified. Under heat and increasing N loads, soluble amino acids derived from glutamate and glutamine were the most responsive metabolites. Foliar metabolic responses to elevated atmospheric CO2 concentrations were dominated by greater production of monosaccharides and associated synthesis of secondary metabolites, such as terpenes, rather than secondary metabolites synthesized along longer sugar pathways involving N-rich precursor molecules, such as those formed from cyclic amino acids and along the shikimate pathway. We suggest that breeding for crop genotypes tolerant to drought and heat stress should be based on their capacity to increase the concentrations of C-rich compounds more than the concentrations of smaller N-rich molecules, such as amino acids. This could facilitate rapid and efficient stress response by reducing protein catabolism without compromising enzymatic capacity or increasing the requirement for re-transcription and de novo biosynthesis of proteins.
Journal Article
Various Analytical Techniques Reveal the Presence of Damaged Organic Remains in a Neolithic Adhesive Collected During Archeological Excavations in Cantagrilli (Florence Area, Italy)
2026
In this work, an archeological adhesive collected at Cantagrilli (near Florence) was chemically analyzed by applying gas chromatography/mass spectrometry, infrared spectroscopy, and nuclear magnetic resonance spectrometry combined with the archeobotanical investigations. Data identify triterpenes, aged anhydride, benzoyl resin, and gelatinized starch in the sample. The multi-analytical approach allowed us to identify some molecular compounds, as well as their state of chemical decomposition (especially by applying the mass spectrometry techniques). On the other hand, archeobotanical measurements have provided useful but not unequivocal information regarding the possible origin of triterpenes from some terrestrial plants, combined with the presence of microorganisms and transformed chemicals (such as starch modified into gelatin). All this information is very useful to Prehistoric Archeologists for understanding the cultural processes and technologies used by ancient populations.
Journal Article
Effects of Longer-Term Mixed Nut Consumption on Lipoprotein Particle Concentrations in Older Adults with Overweight or Obesity
by
Plat, Jogchum
,
Nijssen, Kevin M. R.
,
Chavez-Alfaro, Marco A.
in
Aged
,
Alcohol
,
Apolipoproteins
2025
Background: Recently, we reported that longer-term mixed nut intake significantly reduced serum total and low-density lipoprotein (LDL)-cholesterol, but these markers may not fully capture lipoprotein-related cardiovascular disease (CVD) risk. Objectives: This randomized, controlled, single-blinded, crossover trial in older adults with overweight or obesity examined the effects of longer-term mixed nut consumption on lipoprotein particle size, number, and lipid distribution. Methods: Twenty-eight participants (aged 65 ± 3 years; BMI 27.9 ± 2.3 kg/m2) completed two 16-week periods (control [no nuts] vs. mixed nuts (60 g/day: 15 g of walnuts, pistachios, cashews, and hazelnuts), separated by an 8-week washout. Plasma lipoprotein particle numbers, sizes, and lipid distributions across subclasses were analyzed using high-throughput nuclear magnetic resonance (NMR) spectroscopy. Results: Mixed nut consumption significantly reduced Apolipoprotein B (ApoB) concentrations (−0.07 g/L; p = 0.009), total cholesterol (−0.27 mmol/L; p = 0.047), non-HDL cholesterol (−0.28 mmol/L; p = 0.022), and total triacylglycerol (TAG) (−0.27 mmol/L; p = 0.008). Total very large-density lipoprotein (VLDL) particle numbers decreased by 24 nmol/L (p < 0.001), with reductions observed across all VLDL subclasses. Total LDL particle numbers (p = 0.044), specifically intermediate-density lipoprotein (IDL) (p = 0.002) and large LDL particles (p = 0.015), were also reduced, while HDL particle numbers and sizes were unaffected. The mixed nut intervention significantly reduced cholesterol concentrations across all VLDL subclasses and IDL (all p < 0.01), with no changes in LDL or HDL subclasses. TAG concentrations showed reductions across all lipoprotein subclasses (all p < 0.05). Conclusions: Longer-term mixed nut consumption may lower CVD risk in older adults and favorable shifts in apoB-containing lipoprotein subclasses towards a less atherogenic profile.
Journal Article
Prediagnostic Plasma Metabolomic Profiles Using NMR for Exfoliation Glaucoma Among US Health Professionals
2025
Background: Exfoliation glaucoma (XFG) represents a form of deleterious ocular aging of unclear etiology. We evaluated prediagnostic nuclear magnetic resonance (NMR)-based metabolites in relation to XFG risk, expanding on our prior findings of XFG-related metabotypes using liquid chromatography-mass spectrometry (LC-MS). Methods: We identified 217 XFG cases and 217 matched controls nested within three prospective health professional cohorts with plasma collected a mean 11.8 years before case identification. Plasma metabolites were analyzed using the targeted NMR Nightingale platform. Conditional logistic models and Metabolite Set Enrichment Analysis were performed. Multiple comparison issues were addressed using the number of effective tests (NEF) and false discovery rate (FDR). Results: Among 235 profiled metabolites, higher glucose was significantly associated with a lower risk of XFG (odds ratio (95%CI) = 0.42 (0.26, 0.7); NEF = 0.03). Among metabolite classes, lipoprotein subclasses and branched-chain amino acids were inversely associated, while relative lipoprotein lipid concentrations were adversely associated (FDR < 0.05). Conclusion: NMR profiling revealed that glucose, branched-chain amino acids, lipoprotein subclasses, and relative lipoprotein lipid concentrations may play important roles in XFG etiology.
Journal Article
Metabolomics: A New Tool in Our Understanding of Congenital Heart Disease
2022
Although the genetic origins underpinning congenital heart disease (CHD) have been extensively studied, genes, by themselves, do not entirely predict phenotypes, which result from the complex interplay between genes and the environment. Consequently, genes merely suggest the potential occurrence of a specific phenotype, but they cannot predict what will happen in reality. This task can be revealed by metabolomics, the most promising of the “omics sciences”. Though metabolomics applied to CHD is still in its infant phase, it has already been applied to CHD prenatal diagnosis, as well as to predict outcomes after cardiac surgery. Particular metabolomic fingerprints have been identified for some of the specific CHD subtypes. The hallmarks of CHD-related pulmonary arterial hypertension have also been discovered. This review, which is presented in a narrative format, due to the heterogeneity of the selected papers, aims to provide the readers with a synopsis of the literature on metabolomics in the CHD setting.
Journal Article
The Effect of Alpine Herbs on the Microbiota of In Vitro Rumen Fermentation
2025
Milk from cows grazing on alpine pastures has higher quality than milk from indoor-fed cows, likely due to diet-driven differences in rumen microbiota. We assessed the effects of supplementing alpine herbs—each varying in its content of fiber, protein, and polyphenol—on rumen microbiota via in vitro fermentation, comparing these to a grass hay control using metagenomic sequencing. Fermentations with alpine herbs compared to grass hay control had higher content of fibrolytic Prevotella and lower abundances of Butyrivibrio, Ruminococcaceae, Anaerovibrio, Succiniclasticum, and Desulfovibrio. Fermentations with high starch content (Alchemilla vulgaris, Gallium odoratum and Sanguisorba officinalis) had low, microbial diversity, while fermentations with high content of structural fibre (Sisymbrium officinale, Tanacetum vulgare, and Cicerbita alpina) had high microbial diversity. C. alpina, Sa. officinalis, and T. vulgare fermentations that had high lignin content showed a higher abundance of Bacteroidetes and a lower abundance of Firmicutes. Fermentations with high protein content (G. odoratum and T. vulgare) induced higher abundance of fibrolytic Lachnospiraceae. Sa. officinalis and A. vulgaris fermentations with high content of polyphenols were associated with increased abundances of Streptococcus and family RF-16 and lower abundances of family BS11 and Desulfovibrio. Fermentations with C. alpina and Si. Officinale induced higher abundance of fibrolytic Fibrobacter succinogenes. The beta diversity between fermentations corresponded to differences in the contents of protein, lignin, and polyphenols in the plant material. In conclusion, different herbs can promote the abundance of various fibrinolytic bacteria and change the microbial diversity, which has potential to increase the feed efficiency and the robustness of microbiota and reduce methane production.
Journal Article
The blood serum metabolome profile after different phases of a 4‐km cycling time trial: Secondary analysis of a randomized controlled trial
by
Azevedo, Rafael A.
,
Bertuzzi, Romulo
,
Silva‐Cavalcante, Marcos D.
in
Adult
,
Bicycling
,
Bicycling - physiology
2024
It has been assumed that exercise intensity variation throughout a cycling time trial (TT) occurs in alignment of various metabolic changes to prevent premature task failure. However, this assumption is based on target metabolite responses, which limits our understanding of the complex interconnection of metabolic responses during exercise. The current study characterized the metabolomic profile, an untargeted metabolic analysis, after specific phases of a cycling 4‐km TT. Eleven male cyclists performed three separated TTs in a crossover counterbalanced design, which were interrupted at the end of the fast‐start (FS, 600 ± 205 m), even‐pace (EP, 3600 ± 190 m), or end‐spurt (ES, 4000 m) phases. Blood samples were taken before any exercise and 5 min after exercise cessation, and the metabolomic profile characterization was performed using Nuclear Magnetic Resonance metabolomics. Power output (PO) was also continually recorded. There were higher PO values during the FS and ES compared to the EP (all p < 0.05), which were accompanied by distinct metabolomic profiles. FS showed high metabolite expression in TCA cycle and its related pathways (e.g., glutamate, citric acid, and valine metabolism); whereas, the EP elicited changes associated with antioxidant effects and oxygen delivery adjustment. Finally, ES was related to pathways involved in NAD turnover and serotonin metabolism. These findings suggest that the specific phases of a cycling TT are accompanied by distinct metabolomic profiles, providing novel insights regarding the relevance of specific metabolic pathways on the process of exercise intensity regulation. Highlights Untargeted metabolomic profile analysis may reveal unexplored bioenergetic pathways activated throughout a self‐paced cycling time trial. Exercise intensity variations throughout a cycling time trial are accompanied by different blood serum metabolomic profiles. The current new insights may encourage future investigation on the underpinning mechanisms of specific metabolomic profiles according to each time trial phase.
Journal Article
Research on the quality evaluation of crude drugs
2025
As crude drugs are natural products, their quality may vary. However, the degradation of the active ingredients in the compositional changes that occur during processing and preparation also affects the medicinal properties of the Kampo formula, which uses herbal medicines; therefore, a detailed investigation of the effects of compositional changes during preparation is required. Plant constituents vary in content depending on the year of cultivation and the plant part; however, detailed studies have rarely been reported for some crude drugs. Liquid chromatography-nuclear magnetic resonance/mass spectrometry revealed the degradation process of saponins, which are unstable components of the crude drug “Achyranthes root.” The presence of diterpenes unstable with respect to drying temperature in the leaves of the crude drug “Leonurus herb” was revealed and their structures were elucidated. At the examination stage of the degradation process of perillaldehyde, the characteristic aromatic component of Perilla herb, it was elucidated that some specimens contained a small amount of perillaldehyde and that they contained more α-asarone. A trend toward lower ephedrine content was observed toward the tip of the above-ground branching of the Ephedra herb. Multivariate analysis was also introduced into the quality assessment of crude drugs and was established as a tool to identify bioactive compounds using the component diversity of crude drugs and to elucidate component differences due to the cultivation environment.
Graphic abstract
Journal Article
Singular Structural Features on Humic Fractions in Solution: Statistical Analysis of Diverse Analytical Techniques Spectra
by
González-Vila, Francisco J
,
Baigorri, Roberto
,
Fuentes, Marta
in
accuracy
,
Acids
,
Agronomy. Soil science and plant productions
2010
An adequate knowledge of the chemical and structural features that characterize the main fractions of humic substances in solution is of great interest to better understand a number of processes occurring in nature. Qualitative analysis of the spectra derived from diverse analytical techniques is frequently complicated, however, partially due to the quantity and complexity of the data. In this context, multivariate statistical analysis has proven to be a useful tool to integrate and interpret all this information. In this study, we applied Pareto analysis to the spectrum data derived from the application of diverse analytical techniques to several samples of humic substances. The humic substances considered in the study belong to the following groups: gray humic acid (GHA), brown humic acid (BHA), and fulvic acid (FA). The analytical techniques applied were ultraviolet–visible light, synchronous fluorescence, and Fourier transform infrared spectroscopies, 13C nuclear magnetic resonance spectrometry, and pyrolysis gas chromatography–mass spectrometry. The results show the efficiency of Pareto analysis at discriminating between the different groups of humic substances. This discrimination corresponded to specific spectral regions for each group, which corresponded to singular structural features. Thus, GHA presented a marked aliphatic character and low functionality. The BHA group presented high structural homogeneity characterized by a high aromatic character, including significant ring condensation and complexity, and significant functionality. The FA group was very disperse, with high diversity in functional arrangements of simpler organic molecules, low condensed aromatic rings, and a very high concentration of O-containing functional groups that might be involved in metal intermolecular bridges. A discriminant analysis of data derived from the Pareto analysis confirmed the validity of these singular structural features as representative of each humic substance group.
Journal Article
Synthesis of G0 aminopolyol and aminosugar dendrimers, controlled by NMR and MALDI TOF mass spectrometry
by
Bartkowiak, Grażyna
,
Pyziak, Mikołaj A
,
Popenda, Łukasz
in
Chemical synthesis
,
Dendrimers
,
Fragmentation
2017
Organic compounds designed to serve as stable dendrimer cores were developed. A series of aminosugar and amino polyol containing G0 dendrimers were synthesized. The reaction mixture composition was checked by MALDI TOF mass spectrometry, while that of purified products – by 1H and 13C NMR combined with 2D NMR spectroscopy as well as MALDI TOF MSMS mass spectra. Mass spectrometric fragmentation experiments were performed in positive ion mode in order to determine common fragmentation patterns of [M+H]+ ions.
Journal Article