Quantitative determination of isoflavonoids inOnonisspecies by UPLC-UV-DAD

Introduction The root of theOnonisspecies has been used internally and externally in ethnomedicine for centuries and contains biologically valuable isoflavonoid compounds. Therefore, it is important to obtain quantitative information about the isoflavonoid profile of these plants. Objectives In this article we aimed to develop an optimised sample preparation protocol alongside a validated method for the quantitative measurement of isoflavones, isoflavanones and pterocarpans in the form of glucosides and aglycones, in order to compare the specialised metabolites ofOnonis spinosaL. andO. arvensisL. Material and methods Quantitative determination was carried out by the means of ultra-performance liquid chromatography coupled with ultraviolet diode-array detection (UPLC-UV-DAD). Results An optimised sample preparation method was developed to transform malonyl glucosides to their glucosidic forms. Chromatographic methods were created for the baseline separation of isoflavones, isoflavanones and pterocarpans alongside with their glucosides. Altogether 12 compounds were evaluated quantitatively in samples ofO. spinosaandO. arvensis. Conclusion As a result, no characteristic change could be observed between the two species regarding their isoflavonoid pattern.

Automated summary

Quantitative determination of isoflavones, isoflavanones and pterocarpans was carried out using ultra-performance liquid chromatography coupled with ultraviolet diode-array detection. An optimised sample preparation method was developed to convert malonyl glucosides to their glucosidic forms. Chromatographic methods were established for the baseline separation of the compounds in Ononis spinosa and O. arvensis, with no characteristic change observed between the two species in terms of their isoflavonoid pattern.