Vegetables are a major source of carotenoids and carotenoids are identified as potentially important natural antioxidants that may aid in the prevention of several human chronic degenerative diseases. Characterization of carotenoids in organic biological matrices is a crucial step in any research valorization trajectory. This study reports for the first time the use of high mass resolution and exact mass orbitrap technology for the elucidation of carotenoid fragmentation pathways. This contributes to the generation of new tools for identifying unknown carotenoids based on fragmentation patterns. Two different chromatographic methods making use of different mobile phases resulted in the generation of different ion species because of the large influence of the mobile phase solvent composition on ionization. It was shown that depending on the molecular ion species that are generated (protonated ions or radical molecular ions), different fragments are formed when applying higher energy collisional dissociation. Fragmentation and the abundance of fragments provide valuable structural information on the type of functional groups, the polyene backbone and the location of double bonds in ring structures of carotenoids. Furthermore, coherence between specific substructures in the molecules and characteristic fragmentation patterns was observed allowing the assignment of fragmentation patterns for carotenoid substructures that can theoretically be extrapolated to carotenoids with similar (sub)structures. Differentiation between isomeric carotenoids by compound specific fragments could however not be made for all the isomeric groups under study. As a wide variety of isomeric forms of carotenoids exist in nature, the combination of good chromatographic separation with high resolution mass spectrometry and other complementary qualitative structure elucidation techniques such as a photo diode array detector and/or nuclear magnetic resonance spectroscopy are indispensable for unambiguous identification of unknown carotenoids.

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Several medicinal plants are currently used by the food industry as functional additives, for example botanical extracts in herbal drinks. Moreover, the scientific community has recently begun focusing on halophytes as sources of functional beverages. Helichrysum italicum subsp. picardii (everlasting) is an aromatic halophyte common in southern Europe frequently used as spice and in traditional medicine. In this context, this work explored for the first time H. italicum subsp. picardii as a potential source of innovative herbal beverages with potential health promoting properties. For that purpose, infusions and decoctions were prepared from roots, vegetative aerial-organs (stems and leaves) and flowers and evaluated for in vitro antioxidant and anti-diabetic activities. Samples were also assessed for toxicity in different mammalian cell lines and chemically characterized by spectrophotometric methods and ultra-high performance liquid chromatography-photodiode array-mass-spectrometry (UHPLC-PDA-MS). Results were expressed relating to 'a cup-of-tea' and compared with those obtained with green tea (Camellia sinensis) and rooibos tisane (Aspalathus linearis). Tisanes from the everlasting's above-ground organs, particularly flowers, have high polyphenolic content and several phenolics were identified; the main compounds were chlorogenic and quinic acids, dicaffeoylquinic-acid isomers and gnaphaliin-A. The antioxidant activity of beverages from the everlasting's above-ground organs matched or surpassed that of green tea and rooibos. Its anti-diabetic activity was moderate and toxicity low. Overall, our results suggest that the everlasting is a potential source of innovative and functional herbal beverages.