Liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) has become a workhorse in global metabolomics studies with growing applications across biomedical and environmental ...sciences. However, outstanding bioinformatics challenges in terms of data processing, statistical analysis and functional interpretation remain critical barriers to the wider adoption of this technology. To help the user community overcome these barriers, we have made major updates to the well-established MetaboAnalyst platform ( www.metaboanalyst.ca ). This protocol extends the previous 2011 Nature Protocol by providing stepwise instructions on how to use MetaboAnalyst 5.0 to: optimize parameters for LC-HRMS spectra processing; obtain functional insights from peak list data; integrate metabolomics data with transcriptomics data or combine multiple metabolomics datasets; conduct exploratory statistical analysis with complex metadata. Parameter optimization may take ~2 h to complete depending on the server load, and the remaining three stages may be executed in ~60 min.
“Guava” (Acca sellowiana) is an unconventional edible plant from Brazil. It is used in traditional medicine as an anti-diabetic; however, pharmacological studies on this plant are scarce. This study ...aimed to evaluate the chemical and safety profile of an aqueous A. sellowiana peel extract (ASPE) and its effects on endothelial EA.hy926 cells under glucose overload and in vivo (Artemia salina). An ethanolic extract from A. sellowiana peels (ASPEetOH) was also produced and characterized. Results showed that ASPE did not present in vivo toxicity, and it was found to contain high phenolic content and redox capacity. ASPE (50 µg/mL; 24 h) prevented oxidative stress and mitochondrial dysfunction, besides positively modulating Sirtuins 1 and 3, and prevented the increase of COX-2 and NF-kβ expression levels in EA.hy926 cells under glucose overload. Chromatographic fractionation, metabolite profiling, spectroscopic and bioinformatics analyses revealed the presence of phenolic acids, flavan-3-ols, flavonols, flavones, flavanones, and anthocyanidins, displaying a diversity of compounds in the crude and fractionated ASPEetOH. This study provided evidence on the safety profile, chemical composition, and pharmacological activities of A. sellowiana.
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•Acca sellowiana “guava” is an Unconventional Food Plant from Brazil.•Extract from guava peels (GP) is a source of flavonoids and phenolic acids.•GP improved mitochondrial function in EA.hy92 cells under high glucose.•GP regulated SIRT 1, SIRT 3, COX-2, and NF-kβ endothelial expressions.•GP aqueous extract is in vivo safe.
Microbiotas are a malleable part of ecosystems, including the human ecosystem. Microorganisms affect not only the chemistry of their specific niche, such as the human gut, but also the chemistry of ...distant environments, such as other parts of the body. Mass spectrometry-based metabolomics is one of the key technologies to detect and identify the small molecules produced by the human microbiota, and to understand the functional role of these microbial metabolites. This Review provides a foundational introduction to common forms of untargeted mass spectrometry and the types of data that can be obtained in the context of microbiome analysis. Data analysis remains an obstacle; therefore, the emphasis is placed on data analysis approaches and integrative analysis, including the integration of microbiome sequencing data.
The employment of liquid chromatography-mass spectrometry (LC-MS) untargeted and targeted metabolomics has led to the discovery of novel biomarkers and improved the understanding of various disease ...mechanisms. Numerous strategies have been reported to expand the metabolite coverage in LC-MS-untargeted and targeted metabolomics. To improve the sensitivity of low-abundance or poor-ionized metabolites for reducing the amount of clinical sample, chemical derivatization methods are used to target different functional groups. Proper sample preparation is beneficial for reducing the matrix effect, maintaining the stability of the LC-MS system, and increasing the metabolite coverage. Machine learning has recently been integrated into the workflow of LC-MS metabolomics to accelerate metabolite identification and data-processing automation, and increase the accuracy of disease classification and clinical outcome prediction. Due to the rapidly growing utility of LC-MS metabolomics in discovering disease markers, this review will address the recent advances in the field and offer perspectives on various strategies for expanding metabolite coverage, chemical derivatization, sample preparation, clinical disease markers, and machining learning for disease modeling.
Low-temperature oxidation (LTO) is of great significance for the subsequent oxidation reactions and oil recovery during in-situ combustion. The paper brings an in-depth analysis of crude oil LTO that ...is still not well understood. Firstly, one Xinjiang heavy oil was subjected to LTO reactions under different temperatures conducted in an oxidation reactor. The combustion behaviors of the oxidized oils were then investigated by thermogravimetry and differential scanning calorimetry. The Friedman and Ozawa-Flynn-Wall methods were adopted to perform combustion kinetic analysis of the oxidized oils. Subsequently, both gas chromatograph-mass spectroscopy and negative ion electrospray Fourier transform-ion cyclotron resonance mass spectrometry were introduced as a new route to investigate the compositional changes of crude oil caused by LTO. The condensation of aromatics as well as aromatization and condensation of other compounds was intensified from 40 to 200 °C. Chain saturated aliphatic, monocyclic, bicyclic, and tricyclic naphthenic acids were the main acidic components in the oxidized oils. The relative abundance of chain saturated aliphatic acids and O1 species was decreased from 40 to 200 °C, whereas that of tricyclic naphthenic acids and O3 species was increased. Finally, we summarized LTO reaction pathways of crude oil, which helped to understand LTO mechanisms.
•LTO experiments of heavy oil under different temperatures were implemented.•Effect of LTO on the combustion behaviors and kinetics was investigated.•LTO reactions from 160 to 200 °C contributed to high-temperature combustion.•Compositional changes of heavy oil due to LTO were studied using GC-MS and FT-ICR MS.•LTO reaction pathways of crude oil were summarized.
Improvements in the performance and availability of commercial instrumentation have made ion mobility-mass spectrometry (IM-MS) an increasingly popular approach for the structural analysis of ionic ...species as well as for separation of complex mixtures. Here, a new research instrument is presented which enables complex experiments, extending the current scope of IM technology. The instrument is based on a Waters SYNAPT G2-Si IM-MS platform, with the IM separation region modified to accept a cyclic ion mobility (cIM) device. The cIM region consists of a 98 cm path length, closed-loop traveling wave (TW)-enabled IM separator positioned orthogonally to the main ion optical axis. A key part of this geometry and its flexibility is the interface between the ion optical axis and the cIM, where a planar array of electrodes provides control over the TW direction and subsequent ion motion. On either side of the array, there are ion guides used for injection, ejection, storage, and activation of ions. In addition to single and multipass separations around the cIM, providing selectable mobility resolution, the instrument design and control software enable a range of “multifunction” experiments such as mobility selection, activation, storage, IMS n , and importantly custom combinations of these functions. Here, the design and performance of the cIM-MS instrument is highlighted, with a mobility resolving power of approximately 750 demonstrated for 100 passes around the cIM device using a reverse sequence peptide pair. The multifunction capabilities are demonstrated through analysis of three isomeric pentasaccharide species and the small protein ubiquitin.
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