The role of harmonized, gas and liquid chromatography mass spectrometry in the discovery of the neolignan balanophonin in the fruit wall of Cirsium vulgare

In order to identify and quantify fruit-lignans of Cirsium vulgare – authors introduced a special analysis system: with particular attention to the lignans enrichment/separation course. These synchronized, germination and enzymatic hydrolysis processes were followed by complementary gas and liquid chromatography, coupled with special mass selective detections (GC–MS, LC–MS/MS, LC–TOF/MS) and confirmed by nuclear magnetic resonance (NMR) spectroscopy. Mass fragmentations and NMR evidences, proved that the two main medicinal lignan constituents of the fruits of Cirsium vulgare are the neolignan-type, free balanophonin and the butyrolactone-type tracheloside. As novelty to the field, these two lignans of different chemical structures could be quantitatively extracted, separately from each others, without impurities. Balanophonin and tracheloside do accumulate in the fruits of C. vulgare, separately: balanophonin was found, in enormous high concentrations, in the fruit wall (23.2–24.9 mg/g), while in embryo part tracheloside was determined (20.3 mg/g), exclusively. Consequently, the optimum source of balanophonin proved to be the fruit wall, while tracheloside, – providing trachelogenin upon enzymatic hydrolysis, – could be obtained from the embryo parts of fruits. As further novelties of the study balanophonin was identified and quantified at the first time with on-line chromatographic technique, in free form, without authentic standard compound.