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Antonia Garrido Frenich - One of the best experts on this subject based on the ideXlab platform.

José Luis Martínez Vidal - One of the best experts on this subject based on the ideXlab platform.

Rosa Ma Lamuelaraventos - One of the best experts on this subject based on the ideXlab platform.

  • comprehensive identification of walnut polyphenols by liquid chromatography coupled to linear ion trap Orbitrap Mass Spectrometry
    Food Chemistry, 2014
    Co-Authors: Jorge Regueiro, Claudia Sanchezgonzalez, Maria Izquierdopulido, Rosa Ma Lamuelaraventos, Anna Vallverduqueralt, Jesus Simalgandara
    Abstract:

    Epidemiologic studies and clinical trials have demonstrated consistent benefits of walnut consumption on coronary heart disease risk and other chronic diseases. Walnuts (Juglans regia L.) have been described previously as a rich source of polyphenols with a broad array of different structures. However, an accurate screening of its complete phenolic profile is still lacking. In the present work, liquid chromatography coupled with electrospray ionization hybrid linear trap quadrupole-Orbitrap Mass Spectrometry (LC–LTQ-Orbitrap) was applied for a comprehensive identification of phenolic compounds in walnuts. A total of 120 compounds, including hydrolysable and condensed tannins, flavonoids and phenolic acids were identified or tentatively identified on the base of their retention times, accurate Mass measurements and subsequent Mass fragmentation data, or by comparing with reference substances and literature. The peak area of each signal in Mass chromatograms was used to provide semiquantitative information for comparison purposes. The most abundant ions were observed for ellagitannins, ellagic acid and its derivatives. Furthermore, the high-resolution MS analysis revealed the presence of eight polyphenols that have never been reported in walnuts: stenophyllanin C, malabathrin A, eucalbanin A, cornusiin B, heterophylliin E, pterocarinin B, reginin A and alienanin B.

  • improved characterization of tomato polyphenols using liquid chromatography electrospray ionization linear ion trap quadrupole Orbitrap Mass Spectrometry and liquid chromatography electrospray ionization tandem Mass Spectrometry
    Rapid Communications in Mass Spectrometry, 2010
    Co-Authors: Rosa Ma Lamuelaraventos, Anna Vallverduqueralt, Olga Jauregui, Alexander Medinaremon, Cristina Andreslacueva
    Abstract:

    Tomato (Lycopersicon esculentum Mill.) is the second most important fruit crop worldwide. Tomatoes are a key component in the Mediterranean diet, which is strongly associated with a reduced risk of chronic degenerative diseases. In this work, we use a combination of Mass Spectrometry (MS) techniques with negative ion detection, liquid chromatography/electrospray ionization linear ion trap quadrupole-Orbitrap-Mass Spectrometry (LC/ESI-LTQ-Orbitrap-MS) and liquid chromatography/electrospray ionization tandem Mass Spectrometry (LC/ESI-MS/MS) on a triple quadrupole, for the identification of the constituents of tomato samples. First, we tested for the presence of polyphenolic compounds through generic MS/MS experiments such as neutral loss and precursor ion scans on the triple quadrupole system. Confirmation of the compounds previously identified was accomplished by injection into the high-resolution system (LTQ-Orbitrap) using accurate Mass measurements in MS, MS 2 and MS 3 modes. In this way, 38 compounds were identified in tomato samples with very good Mass accuracy (<2 mDa), three of them, as far as we know, not previously reported in tomato samples. Copyright # 2010 John Wiley & Sons, Ltd.

Cong Kong - One of the best experts on this subject based on the ideXlab platform.

  • Multi-Residue Screening of Pesticides in Aquaculture Waters through Ultra-High-Performance Liquid Chromatography-Q/Orbitrap Mass Spectrometry
    Water, 2020
    Co-Authors: Shou-ying Wang, Essy Kouadio Fodjo, Cong Kong
    Abstract:

    Pesticide residues in foodstuffs can lead to several undesirable effects. A simple and high-throughput targeted screening method analyzing multi-residue pesticide in aquaculture water based on ultra-high-performance liquid chromatography-Q/Orbitrap Mass Spectrometry (UHPLC-Q/Orbi MS) was developed and validated. In this technique, the peaks of the compound using precursor ions were recorded by the full scan, which was used for rough quantitative analysis with single point matrix matched calibration. The qualitative identification was performed following the stringent confirmation criteria with fragment ions, retention time, and an isotopic pattern. Additionally, solid-phase extraction with an HLB (Hydrophilic/Lipophilic Balanced) column was selected to enrich and separate target pesticides from water. The screening detection limit of 33 compounds are less than 2 ng·L−1, while 26 compounds range from 2 ng·L−1 to 10 ng·L−1, 19 compounds are at the range of 10–200 ng·L−1, and the other two compounds are 200 ng·L−1 and 1000 ng·L−1. Most of the recovery results were found to be between 60~130%. Finally, the method was successfully applied to the analysis of pesticide residues in 30 water samples from aquaculture environment in Shanghai, indicating its applicability in pesticide screening for environmental monitoring.

  • Simultaneous determination of ten aminoglycoside antibiotics in aquatic feeds by high-performance liquid chromatography quadrupole-Orbitrap Mass Spectrometry with pass-through cleanup.
    Chirality, 2019
    Co-Authors: Xiaoyi Lou, Yunyu Tang, Changling Fang, Cong Kong, Yongfu Shi, Dongmei Huang, Yaoguang Guo, Dongxue Xiao
    Abstract:

    A simple and sensitive method has been established based on pass-through cleanup and high-performance liquid chromatography quadrupole-Orbitrap Mass Spectrometry (HPLC-Q/Orbitrap MS) for the simultaneous determination of ten aminoglycosides (AGs) in aquatic feeds. The extraction solution and cleanup procedure had been optimized, and good sensitivity, accuracy, and precision were obtained. The calibration curves of AGs were linearity (R2 > 0.99) in the range of 2.0 to 200 μg/L (or 5.0 to 500 μg/L). The limits of detection of AGs were between 10 and 25 μg/kg. The recoveries of AGs ranged from 74.9% to 94.3%, and the intraday and interday relative standard deviations were less than 15%. Finally, this method was successfully applied to determine ten AGs in 30 aquatic feed samples. It might be the first time to use pass-through cleanup approach combined with HPLC-Q/Orbitrap MS method for AGs determination in aquatic feed samples.

  • Multiclass screening of >200 pharmaceutical and other residues in aquatic foods by ultrahigh-performance liquid chromatography-quadrupole-Orbitrap Mass Spectrometry.
    Analytical and bioanalytical chemistry, 2018
    Co-Authors: Cong Kong, Wang Yang, Yuanfei Huang
    Abstract:

    A quick screening method of more than 200 pharmaceutical and other residues in aquatic foods based on ultrahigh-performance liquid chromatography–quadrupole-Orbitrap Mass Spectrometry (UHPLC-Q/Orbitrap MS) was established. In this method, after the addition of 200 μL of 1 M EDTA-Na2, 2 g of each sample homogenate was extracted successively with 10 mL of acetonitrile and 10 mL of ethyl acetate. The extracts were combined, dried under nitrogen flow, and redissolved in 0.1% formic acid in acetonitrile/water (4:6, v/v) for analysis. The prepared samples were analyzed by UHPLC- Q/Orbitrap MS system in Full MS/ddMS2 (full-scan data-dependent MS/MS) mode. Compound identification was performed through comparison of the sample data with the database for standard chemicals, including the retention time, precursor ion, product ions, and isotope pattern for all 206 compounds. Five different aquatic food matrices (carp, shrimp, crab, eel, and mussel) spiked with the analytes at 1, 10, and 50 ng/g were evaluated to assess recoveries, precision, matrix effects, stability, and detection limits using the method. UHPLC analyses required 25 min, and 178–200 analytes met identification criteria at 50 ng/g depending on the matrix. Furthermore, practical application of this method for real samples displayed strong screening capability.

Vadims Bartkevics - One of the best experts on this subject based on the ideXlab platform.