Identification of flavonoids using liquid chromatography with electrospray ionization and ion trap tandem mass spectrometry with an MS/MS library

Abstract

Searchable MS/MS spectra libraries, constructed using the results of liquid chromatography coupled with electrospray ionization (ESI) tandem mass spectrometry (LC/MS/MS) with data-dependent acquisition on an ion trap mass spectrometer, are presented with regard to the identification and confirmation of a variety of closely related flavonoids in a set of biological samples. Flavonoids were found to exhibit a maximum amount of structurally specific MS/MS spectra at 45% of normalized collision energy on the instrument used, without wideband activation. These MS/MS spectra were then searched automatically against a 297-substance MS/MS library that contains many previously acquired spectra of standard flavonoids. The possible applications of this powerful technique to biological samples are also discussed. Daidzein and genistein were identified through the MS/MS spectra library while searching through LC/MS/MS data for plant and microbial extracts. Moreover, these compounds proved completely distinguishable from other flavonoids of closely related structures in the MS/MS spectra library, using the NIST MS search program. The applicability of the library-searchable spectra at low concentrations was demonstrated by successful identification of daidzein and genistein at 0.05 and 0.5 microg/mL, respectively.

Biosynthesis of plant-specific phenylpropanoids by construction of an artificial biosynthetic pathway in Escherichia coli

“…We further analyzed these compounds by LC-MS in negativeion mode. Naringenin was identiWed by LC-MS (m/z 271.26 [M-H] ¡ ) through comparison of the obtained fragmentation pattern with that of an authentic standard and literature data [16]. The production of naringenin using our strategy was 5.3 § 1.3 mg/L.…”

“…HPLC separations were performed using a Finnigan Surveyor HPLC System unit (Thermo Electron) using a hydrosphere C18 column (50 £ 2.0 mm, 5 m; YMC, Kyoto, Japan). The system was operated using a previously described procedure with minor modiWcation [16]. Data-dependent tandem mass spectrometry experiments were controlled using menudriven software provided with the Xcalibur system.…”

Evaluation of glycosylation and malonylation patterns in flavonoid glycosides during LC/MS/MS metabolite profiling

“…The construction of a universal database of CID/MS/MS spectra of flavonoid glycoconjugates joining information obtained in different laboratories will be possible only by taking these MS parameters into account. 40 This is particularly important for inter-laboratory comparison of the MS patterns of isomeric compounds.…”

Systematic bottom-up approach for flavonoid derivative screening in plant material using liquid chromatography high-resolution mass spectrometry

“…Attraction towards mass spectrometry (MS)-based profiling methods of flavonoids has also increased in the recent years [12,[16][17][18][19]. Mass spectrometry usually with electrospray ionization often combined with a diode array detector appeared to be the most important technique for flavonoid profiling.…”