Metabolomics Based on UHPLC-Orbitrap-MS and Global Natural Product Social Molecular Networking Reveals Effects of Time Scale and Environment of Storage on the Metabolites and Taste Quality of Raw Pu-erh Tea

2019 ◽  
Vol 67 (43) ◽  
pp. 12084-12093 ◽  
Author(s):  
Shanshan Xu ◽  
Jing-Jing Wang ◽  
Yuming Wei ◽  
Wei-Wei Deng ◽  
Xiaochun Wan ◽  
...  
Keyword(s):  
Natural Product ◽  
Time Scale ◽  
Taste Quality ◽  
Molecular Networking ◽  
Orbitrap Ms

Targeted and nontargeted metabolomics analysis for determining the effect of storage time on the metabolites and taste quality of keemun black tea

2021 ◽  
Vol 359 ◽  
pp. 129950
Author(s):  
Ai Huang ◽  
Zongde Jiang ◽  
Meng Tao ◽  
Mingchun Wen ◽  
Zhipeng Xiao ◽  
...  
Keyword(s):  
Storage Time ◽  
Black Tea ◽  
Taste Quality ◽  
Metabolomics Analysis

scholarly journals The Tripod for Bacterial Natural Product Discovery: Genome Mining, Silent Pathway Induction, and Mass Spectrometry-Based Molecular Networking

mSystems ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Daniela B. B. Trivella ◽  
Rafael de Felicio
Keyword(s):  
Mass Spectrometry ◽  
Natural Products ◽  
Natural Product ◽  
Biosynthetic Pathway ◽  
Genome Mining ◽  
Chemical Compounds ◽  
Gene Clusters ◽  
Tandem Mass ◽  
Molecular Networking ◽  
Natural Product Discovery

ABSTRACT Natural products are the richest source of chemical compounds for drug discovery. Particularly, bacterial secondary metabolites are in the spotlight due to advances in genome sequencing and mining, as well as for the potential of biosynthetic pathway manipulation to awake silent (cryptic) gene clusters under laboratory cultivation. Further progress in compound detection, such as the development of the tandem mass spectrometry (MS/MS) molecular networking approach, has contributed to the discovery of novel bacterial natural products. The latter can be applied directly to bacterial crude extracts for identifying and dereplicating known compounds, therefore assisting the prioritization of extracts containing novel natural products, for example. In our opinion, these three approaches—genome mining, silent pathway induction, and MS-based molecular networking—compose the tripod for modern bacterial natural product discovery and will be discussed in this perspective.

scholarly journals Molecular Networking: A Useful Tool for the Identification of New Psychoactive Substances in Seizures by LC–HRMS

2020 ◽  
Vol 8 ◽  
Author(s):  
Flaminia Vincenti ◽  
Camilla Montesano ◽  
Francesca Di Ottavio ◽  
Adolfo Gregori ◽  
Dario Compagnone ◽  
...  
Keyword(s):  
Natural Product ◽  
Illicit Drugs ◽  
Synthetic Cannabinoids ◽  
New Psychoactive Substances ◽  
Nmr Analysis ◽  
Psychoactive Substances ◽  
Molecular Networking ◽  
Fentanyl Analogs ◽  
Global Concern ◽  
Product Search

New Psychoactive Substances (NPS) are a global concern since they are spreading at an unprecedented rate. Despite their commerce still being limited compared to traditional illicit drugs, the identification of NPS in seizures may represent a challenge because of the variety of possible structures. In this study we report the successful application of molecular networking (MN) to identify unexpected fentanyl analogs in two seizures. The samples were extracted with 1 mL of methanol and analyzed with an untargeted data-dependent acquisition approach by LC–HRMS. The obtained data were examined using the MN workflow within the Global Natural Product Search (GNPS). A job was submitted to GNPS by including both seizures and standard mixtures containing synthetic cannabinoids and fentanyls raw files; spectra obtained from standards were used to establish representative networks for both molecular classes. All synthetic cannabinoids in the mixture were linked together resulting in a molecular network despite their different fragmentation spectra. Looking at fentanyls, all the molecules with the typical 188.143 and 105.070 fragments were combined in a representative network. By exploiting the standard networks two unexpected fentanyls were found in the analyzed seizures and were putatively annotated as para-fluorofuranylfentanyl and (iso)butyrylfentanyl. The identity of these two fentanyl analogs was confirmed by NMR analysis. Other m/z ratios in the seizures were compatible with fentanyl derivatives; however, they appeared to be minor constituents, probably impurities or synthetic byproducts. The latter might be of interest for investigations of common fingerprints among different seizures.

scholarly journals A catalogue of Locus Algorithm pointings for optimal differential photometry for 23 779 quasars

2020 ◽  
Vol 498 (3) ◽  
pp. 3720-3729
Author(s):  
Oisín Creaner ◽  
Kevin Nolan ◽  
Niall Smith ◽  
David Grennan ◽  
Eugene Hickey
Keyword(s):  
Time Scale ◽  
Figure Of Merit ◽  
Target Object ◽  
Sloan Digital Sky Survey ◽  
Field Of View ◽  
Computing Paradigm ◽  
Sky Survey ◽  
Differential Photometry ◽  
Suitable Reference

ABSTRACT This paper presents a catalogue of optimized pointings for differential photometry of 23 779 quasars extracted from the Sloan Digital Sky Survey (SDSS) Catalogue and a Score for each indicating the quality of the Field of View (FoV) associated with that pointing. Observation of millimagnitude variability on a time-scale of minutes typically requires differential observations with reference to an ensemble of reference stars. For optimal performance, these reference stars should have similar colour and magnitude to the target quasar. In addition, the greatest quantity and quality of suitable reference stars may be found by using a telescope pointing which offsets the target object from the centre of the FoV. By comparing each quasar with the stars which appear close to it on the sky in the SDSS Catalogue, an optimum pointing can be calculated, and a figure of merit, referred to as the ‘Score’ is calculated for that pointing. Highly flexible software has been developed to enable this process to be automated and implemented in a distributed computing paradigm, which enables the creation of catalogues of pointings given a set of input targets. Applying this technique to a sample of 40 000 targets from the fourth SDSS quasar catalogue resulted in the production of pointings and Scores for 23 779 quasars based on their magnitudes in the SDSS r-band. This catalogue is a useful resource for observers planning differential photometry studies and surveys of quasars to select those which have many suitable celestial neighbours for differential photometry.

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