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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.

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 (r2 = 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 (

α-Dicarbonyl (α-DC) compounds were characterised in roasted (coffee, barley coffee) and in fermented (soy sauce) food matrices. Glyoxal (GO), methylglyoxal (MGO), diacetyl (DA) and 3-deoxyglucosone (3-DG) were found in all samples, and hydroxypyruvaldehyde and 5-hydroxypentane-2,3-dione in barley and soy. Cis and trans 3,4-dideoxyglucosone-3-ene (3,4-DGE) isomers and 4-glucosyl-5,6-dihydroxy-2-oxohexanal (4-G,3-DG) were found only in barley, and 3,4-DGE only in soy sauce with molasses. GO, MGO, and DA were quantified. Findings indicate that i) α-DC profiles depend on the food matrix and any technological treatments applied; ii) α-DC quantitation by HPLC requires matrix-specific, validated methods; iii) GO and MGO were the most abundant α-DCs; and iv) barley coffee was the matrix richest in α-DCs both qualitatively and quantitatively. In vitro simulated digestion reduced (coffee) or strongly increased (barley, soy sauce) free α-DC content. These findings suggest that α-DC bioavailability could actually depend not on food content but rather on reactions occurring during digestion.

Red skin radishes (Raphanus savitus L. var. “Cherry Belle”) were extracted employing an environmentally friendly method and the obtained polyphenolic extract was characterized and studied for its applicability as a natural antioxidant colorant in nutraceutical/food and cosmetic fields. Fourteen anthocyanins, fourteen phenolic acid derivatives, and twelve flavonoids were detected. Color stability of the extract submitted to different stress conditions (thermal treatment, light and oxygen exposure) was studied both in liquid and in solid state by monitoring the absorbance at the wavelength of maximum absorption of anthocyanins when present in solutions and by estimating CIEL*a*b* parameters when mixed with mPEG. The investigation indicated a good stability at low temperatures and up to 20 °C, that was higher in the absence of oxygen and at the solid state, whereas the stability decreased at higher temperature. Therefore the extract could be used to color or improve the color of packaged food and cosmetic products to be stored at room temperature.

Two sensitive and selective methods were developed for the evaluation of α-phenylethylamine (α-PEA), an impurity possibly present in the antibiotic phosphomycin (PHO). The reversed-phase high-performance liquid chromatographic method uses a LiChrosorb NH2 column with acetonitrile-0.1M NaH2PO4 · H2O buffer as eluent and allows the simultaneous detection of PHO and α-PEA in a complex matrix such as pharmaceutical preparations. The amine gives a linear detection response over the range 15–85 μg/ml. The derivative spectrophotometric method can specifically discriminate the amine in the range 230–280 nm. The α-PEA concentration is determined by measuring the distance between the maximum at 250 nm and the adjoining minimum at 248 nm in the second-derivative spectrum. A linear correlation was found in the concentration range 15–160 μg/ml. For both procedures, no sample pretreatment is required.

The effect of water activity (aw 0.98, 0.84 and 0.60) and reaction temperature (100, 120, 140 and 160 degrees C) on the mutagenic activity of the Maillard reaction products in heated ribose-lysine and glucose-lysine model systems, was investigated. In the ribose-lysine system, heated at 100 degrees C, the mutagenic activity of the mixture increased as the water activity was lowered. On the contrary, no dependence between mutagenic activity and water activity was observed in the glucose-lysine system. At higher temperatures, in both systems, the presence in the browned mixtures of an antibacterial activity interfering with the bacterial mutagenicity assay was observed. Under all the conditions tested, the ribose-lysine system turned out to be the most reactive by producing higher levels of mutagens. Furthermore, in this system, the antimicrobial interference was more easily detectable. In the model systems used, the browning reaction mixtures were analysed for their absorption spectrum between 200-460 nm, and for the accumulation of furfurals. The results obtained showed that, at temperatures between 120 and 140 degrees C there is a correlation among reaction temperature, absorbance at 420 and around 280 nm, mutagenic activity of the mixture and the level of furfurals. Changes in the levels of furfurals can be related to changes in mutagenicity of the browned mixtures.

The stability with time of browned mixtures characterized by different water activities (aw 0.98, 0.84 and 0.60) and heating temperatures (100, 120, 140 and 160 degrees C) was analysed using the ribose-lysine model system. The results obtained demonstrated the occurrence, during storage, of changes both in the composition of the browned mixtures and in their mutagenic properties, as detected with the Ames test. Only the browned mixtures obtained at 100 degrees C showed a progressive increase in mutagenicity during storage, matched by an increase in ultraviolet and visible light absorbance and of furfural content. In the browning mixtures characterized by a more advanced stage of the Maillard reaction, in which mutagenic activity had initially been found to be undetectable, such activity became evident during storage.