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A new method using Hydrophilic Interaction Liquid Chromatography and UV detection was developed for the determination of free quinic acid in fourteen commercial beverages (fruit juices, red wine, coffee, vinegar, and edible mushroom extract). Samples were directly injected into the HPLC system after dilution and centrifugation. All separations were carried out by gradient elution on a ZIC ® -cHILIC column, using an eluent consisting of acetonitrile and aqueous phosphate buffer at pH 6. Quinic acid eluted in 12 min as a symmetric peak well separated from all other peaks in the chromatograms. The total turnaround time per sample was 60 min. The method was validated using cranberry juice as model beverage matrix. Linearity was demonstrated on spiked juice between 200 and 600 μg/mL ( r 2 = 0.999), and precision and accuracy were satisfactory (RSD ≤ 10% and recovery 100 ± 1%, respectively). The method was proven to be suitable for its purpose. Quinic acid levels ranged from undetectable (<15 μg/mL in red grape juice, elderberry juice, and in red wine vinegar) to 740 ± 30 μg/mL (in mushroom extract). The results were discussed in comparison with the previous reports on similar matrices using different HPLC separation modes. [ABSTRACT FROM AUTHOR]

Today the consumption of fresh vegetables is highly recommended not only for the intake of nutrients, but also for the healthy properties of secondary metabolites involved in the prevention of many disorders. In the present work, phenolic acids and flavonoids extracted from four green ( Cichorium intybus var. sativus and var. foliosum ) and a red spotted (a cross between C. intybus var. silvestre cv “Treviso” and C. endivia var. foliosum ) salads were characterized by high-performance liquid chromatography–electrospray ionization/mass spectrometry. Among the 76 compounds detected in this work, five organic acids (two malic acid derivatives, two pyroglutamic hexoside isomers, and cis -aconitic acid), ten hydroxycinnamic acid derivatives (ferulic, malonyl caffeoylquinic, and caffeoylmethylglutaroylquinic acids, cinnamoyl- and caffeoyl-malate, coumaroyl, sinapoyl, feruloyl, and coumaroylcaffeoyl glycosides, dicaffeoyl lactone, 3- O -caffeoyl-4- O -(3-hydroxyglutaroylquinic acid), four flavonols (quercetin-di- O -glucoside, quercetin-3- O -malonylh exo syl-7- O -h exo side, myricetin-3- O- glucoside, and isorhamnetin-3- O -glucoside), and cyanidin-3- O -glucuronyl-5- O -h exo side have been identified in chicory salads for the first time. These data, together with the results obtained in our previous investigations on Cichorium genus Italian salads, provide a contribution to a more exhaustive identification of the secondary metabolites profile of each considered plant, that could be also useful in building/selecting hybrids with agronomic and peculiar healthy features, even using traditional methods of cultivation. [ABSTRACT FROM AUTHOR]