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N Fuzzati - One of the best experts on this subject based on the ideXlab platform.

Ioannis P Gerothanassis - One of the best experts on this subject based on the ideXlab platform.

  • identification of the major constituents of hypericum perforatum by lc spe nmr and or lc ms
    Phytochemistry, 2007
    Co-Authors: Evangelos C Tatsis, Sjef Boeren, Vassiliki Exarchou, Anastassios N Troganis, Jacques Vervoort, Ioannis P Gerothanassis
    Abstract:

    Abstract The newly established hyphenated instrumentation of LC/DAD/SPE/NMR and LC/UV/(ESI)MS techniques have been applied for separation and structure verification of the major known constituents present in Greek Hypericum perforatum extracts. The chromatographic separation was performed on a C18 column. Acetonitrile-water was used as a mobile phase. For the on-line NMR detection, the analytes eluted from column were trapped one by one onto separate SPE cartridges, and hereafter transported into the NMR flow-cell. LC/DAD/SPE/NMR and LC/UV/MS allowed the characterization of constituents of Greek H. perforatum, mainly naphtodianthrones (hypericin, pseudohypericin, protohypericin, protopseudohypericin), phloroglucinols (hyperforin, Adhyperforin), flavonoids (quercetin, quercitrin, isoquercitrin, hyperoside, astilbin, miquelianin, I3,II8-biapigenin) and phenolic acids (chlorogenic acid, 3-O-coumaroylquinic acid). Two phloroglucinols (hyperfirin and adhyperfirin) were detected for the first time, which have been previously reported to be precursors in the biosynthesis of hyperforin and Adhyperforin.

  • Identification of the major constituents of Hypericum perforatum by LC/SPE/NMR and/or LC/MS.
    Phytochemistry, 2006
    Co-Authors: Evangelos C Tatsis, Sjef Boeren, Vassiliki Exarchou, Anastassios N Troganis, Jacques Vervoort, Ioannis P Gerothanassis
    Abstract:

    Abstract The newly established hyphenated instrumentation of LC/DAD/SPE/NMR and LC/UV/(ESI)MS techniques have been applied for separation and structure verification of the major known constituents present in Greek Hypericum perforatum extracts. The chromatographic separation was performed on a C18 column. Acetonitrile-water was used as a mobile phase. For the on-line NMR detection, the analytes eluted from column were trapped one by one onto separate SPE cartridges, and hereafter transported into the NMR flow-cell. LC/DAD/SPE/NMR and LC/UV/MS allowed the characterization of constituents of Greek H. perforatum, mainly naphtodianthrones (hypericin, pseudohypericin, protohypericin, protopseudohypericin), phloroglucinols (hyperforin, Adhyperforin), flavonoids (quercetin, quercitrin, isoquercitrin, hyperoside, astilbin, miquelianin, I3,II8-biapigenin) and phenolic acids (chlorogenic acid, 3-O-coumaroylquinic acid). Two phloroglucinols (hyperfirin and adhyperfirin) were detected for the first time, which have been previously reported to be precursors in the biosynthesis of hyperforin and Adhyperforin.

F Villa - One of the best experts on this subject based on the ideXlab platform.

B Gabetta - One of the best experts on this subject based on the ideXlab platform.

Piergiorgio Pietta - One of the best experts on this subject based on the ideXlab platform.

  • high performance liquid chromatography electrospray mass spectrometry of hypericum perforatum extracts
    Rapid Communications in Mass Spectrometry, 2000
    Co-Authors: Pierluigi Mauri, Piergiorgio Pietta
    Abstract:

    Hypericum perforatum L. (St. John's Wort) is a widely distributed herbaceous perennial plant which has been well known as a medicinal plant since antiquity. In recent years, H. perforatum has received increasing attention for the treatment of depression and other neuralgic disorders. The main constituents of H. perforatum extract include flavonoids, naphthodianthrones, phloroglucinols, essential oils and xanthones. The present work reports the analysis of naphthodianthrones and phloroglucinols in H. perforatum extracts by means of high performance liquid chromatography (HPLC) coupled simultaneously to a diode array detector (DAD) and electrospray mass spectrometry (ESI-MS). Hypericin, pseudohypericin, hyperforin and Adhyperforin were separated and identified on the base of their on-line UV and mass spectra. Quantitative analysis of hypericin derivatives in different extracts of H. perforatum using DAD and MS detectors was performed. In addition, direct infusion ESI-MS of H. perforatum extracts was applied to obtain rapid mass fingerprints of constituents present in the sample.