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In this work the enantiomeric distribution of chiral coumarins (meranzin and epoxyaurapten), and furocoumarins (oxypeucedanin, byakangelicol, and epoxybergamottin) in different Citrus essential oils (lemon, lime, grapefruit, and bitter orange) was determined by means of a heart-cutting multidimensional-liquid chromatography (MD-LC) system, equipped with a microsilica column in the first dimension in a combination to a cellulosic-based chiral column used in the second dimension. The normal phase-liquid chromatography-liquid chromatography (NP-LC-LC) instrumentation was equipped with a photodiode array detector and a multiport valve as interface. For method optimization and the determination of absolute configuration, natural compounds were isolated and racemic mixture was synthesized. The NP-LC-LC/PDA (where PDA is photodiode array) method provided a good baseline separation of chiral coumarins (meranzin and epoxyaurapten) and furocoumarins (epoxybergamottin and byakangelicol) present in cold-pressed Citrus essential oils without any sample pretreatment. Results obtained showed that for all the chiral compounds present in Citrus essential oils analyzed, there is always a clear prevalence of one of the two enantiomers, and do not appear influenced by the different geographical origin of the oils.

In this work, the suitability of a new polymer family has been investigated as capillary coatings for the analysis of peptides and basic proteins by CE. This polymer family has been designed to minimize or completely prevent protein-capillary wall interactions and to modify the EOF. These coating materials are linear polymeric chains bearing as side cationizable moiety a dentronic triamine derived from N,N,N',N'-tetraethyldiethylenetriamine (TEDETA), which is linked to the backbone through a spacer (unit labeled as TEDETAMA). Four different polymers have been prepared and evaluated: a homopolymer which comprised only of those cationizable repetitive units of TEDETAMA, and three copolymers that randomly incorporate TEDETAMA together with neutral hydrosoluble units of N-(2-hydroxypropyl) methacrylamide (HPMA) at different molar percentages (25:75, 50:50 and 75:25). It has been demonstrated that the composition of the copolymers influences the EOF and therefore the separation of the investigated biopolymers. Among the novel polymers studied, poly-(TEDETAMA-co-HPMA) 50:50 copolymer was successfully applied as coating material of the inner capillary surface in CE-UV and CE-MS, providing EOF reversing together with fast and efficient baseline separation of peptides and basic proteins. Finally, the feasibility of the polymer-coated capillary was shown through the analysis of lysozyme in a cheese sample.

A number of studies have demonstrated positive effects of pistachio consumption in modifying lipid risk factors for coronary heart disease. The aim of the present study was to characterize pistachio polyphenols, carotenoids and tocopherols and investigate their bioaccessibility during digestion. A dynamic gastric model of digestion which provides a realistic and predictive simulation of the physical and chemical processing and accurately mimics both the transit time and the luminal environment within the human stomach was used for the digestion studies. Raw, roasted salted pistachios and muffins made with raw pistachios were tested. Results showed that pistachio polyphenols (59–63 mg/100 g), carotenoids (lutein 11–16 mg/100 g) and tocopherols (227–236 mg/100 g) are bioaccessible during digestion and therefore available for absorption in the gastrointestinal tract. No significant differences in bioaccessibility were observed between raw and roasted pistachios in the stomach and small intestine.However, the presence of muffin limited the release of protocatechuic acid and luteolin in the gastric and duodenal compartment. Polyphenols, carotenoid and tocopherol absorption would contribute to the beneficial relationship between pistachio consumption and health‐related outcomes.This work has been funded by the American Pistachio Growers.