Combination of electrochemical unit and ESI‐MS in fragmentation of flavonoids

Abstract

Introduction: Predictive approaches on the activity of natural compounds based on the fragmentation by instrumental techniques are important for consideration of such molecules as drug candidates and defining new structures with promising properties. Since flavonoids are well-known antioxidants, their redox properties can be related to their pharmacological activity. Objectives: In this work, the potential of electrochemical unit coupled to electrospray ionisation mass spectrometry (ESI-MS) was assessed for fragmentation activity relationships studies of selected flavonoids. Methodology: Methodology of this research included electrochemical conversion of standards of flavonoids at different pH values and their further analysis with the use of ESI-MS. In addition, signals obtained from the blank samples were also identified and used for interpretation due to electrochemical nature of the ESI source. Half maximal inhibitory concentration (IC 50 ) values of flavonoids for 2,2 0 -azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant activity assays were analysed for possible correlation with the structures of flavonoids and products of electrochemical conversion.Results: Fragmentation activity relationships were suggested using the proposed approach and for some of the flavonoids it was not specific enough to determine the input of a particular structural feature to the activity, but for others they were in agreement with those found in the literature. Obtained results showed potential of the proposed approach for application in plant sciences as a fast pre-screening tool for newly isolated bioactive compounds.

Thiogenistein—Antioxidant Chemistry, Antitumor Activity, and Structure Elucidation of New Oxidation Products

“…The ROXY™ electrochemical system is a technique that can be applied for mimicking drug metabolism [ 30 , 31 ] or for interaction studies [ 32 ] as well as other electrochemical cells coupled on-line to the electrospray ionisation (ESI)-MS for study of biological redox reactions [ 33 ]. In the work of Sagandykova and co-workers [ 34 ], the electrochemical unit coupled to ESI-MS was used for fragmentation activity relationships of selected flavonoids. Selected compounds were subjected to electrochemical degradation and the differences in formed products were analysed for correlation with their structures and antioxidant activity.…”

Electrochemical Profiling of Plants

“…It ensures the correct analyte identity when compared with a reference library. The confirmation of identities can be achieved by negative ion ESI-MS using authentic reported samples [49]. However, a robust technique to overcome issues of the non-selective extraction and determination of the comprehensive profiling of contents, i.e., folates, polyglutamated status, flavones, etc., has not yet been developed.…”

Comprehensive profiling of chemical composition of Gleditsiae spina using ultra‐high‐performance liquid chromatography coupled with electrospray ionization quadrupole time‐of‐flight mass spectrometry

“…Therefore, it is essential to develop a rapid and effective analytical method for identifying the chemical components of GS systematically and comprehensively. Ultra‐high‐performance liquid chromatography–quadrupole time‐of‐flight–tandem mass spectrometry (UHPLC–QTOF–MS/MS) coupled with data mining strategy allows rapid identification of Chinese herbal medicine constituents and detection of potential new compounds 13–18 ; due to these advantages over traditional extraction and separation methods, the technology is widely utilized in the manifestation of TCM ingredients 19–24 …”

“…Ultra-high-performance liquid chromatography-quadrupole time-offlight-tandem mass spectrometry (UHPLC-QTOF-MS/MS) coupled with data mining strategy allows rapid identification of Chinese herbal medicine constituents and detection of potential new compounds [13][14][15][16][17][18] ; due to these advantages over traditional extraction and separation methods, the technology is widely utilized in the manifestation of TCM ingredients. [19][20][21][22][23][24] At present, only a few comprehensive profiles of GS chemical composition have been reported. 25 Besides, their identification mode mainly depended on the databases susceptible to imperfection accredited to nonuniform liquid-phase MS conditions and incompetency for identifying novel compounds.…”