An integrated approach to the evaluation of a metabolomic fingerprint for a phytocomplex. Focus on artichoke [Cynara cardunculus subsp. scolymus] leaf.

The availability of reliable herbal formulations is essential in order to assure the maximal activity and to limit unwanted side-effects. The correct concentration of declared components of herbal products is a matter of health legislation and regulation, but is still a topic under debate in the field of quality control assessment. In the present work specific constituents of artichoke leaf extracts, considered as a test herbal product, were measured by standard spectrophotometric and HPLC methods (for quantitative determination of some components only), and results were correlated with the ESI-MS (showing the full metabolomic fingerprint). Phytocomplex stability over time was also investigated in batches submitted to different storage conditions. The results indicated excellent agreement between the two approaches in the measurement of total caffeoylquinic acids and chlorogenic acid contents, but the metabolomic ESI-MS method approach provides a more complete evaluation and monitoring of the composition of a herbal product, without focusing only on a single/few compound measurements. Therefore, the ESI-MS method can be proposed for the evaluation of the quality of complex matrices, such as those in a phytocomplex. Another aspect lies in the possibility to obtain a broad-spectrum stability control of herbal formulations, requiring minimal sample pre-processing procedures.