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Identification of phenolic constituents in red chicory salads (Cichorium intybus) by high-performance liquid chromatography with diode array detection and electrospray ionisation tandem mass spectrometry
No full textPhenolic acids and flavonoids extracted from several types of Cichorium intybus var. silvestre salads
(‘‘Chioggia’’, ‘‘Treviso’’, ‘‘Treviso tardivo’’, and ‘‘Verona’’) were characterised by high-performance liquid
chromatography–electrospray ionisation/mass spectrometry. Among the 64 compounds detected, several
hydroxycinnamic acid derivatives including 8 mono- and dicaffeoylquinic acids, 3 tartaric acid derivatives,
31 flavonol and 2 flavone glycosides, as well as 10 anthocyanins were characterised based on UV
spectra and MSn fragmentation patterns. Furthermore, several isomers of caffeic acid derivatives were
distinguished for the first time by their specific mass spectral data. This is the first study reporting the
glycosylation type and position of mono- and diglycosylated flavonoids in red salads
Phenolic compounds in Cichorium endivia vegetables
No full textPolyphenols are biologically active compounds widely distributed in the plant kingdom and so present in plant-derived foods and intrinsic components of human diets. They have been shown to possess a range of biological activities that are consistent with them contributing to the protection afforded by a diet rich in fruit and vegetables against degenerative diseases1-2. In particular, caffeic acid derivatives act as anti-inflammatory3, skin photo damage protectors and recently chicoric acid showed anti HIV-1 activity4-5. The levels and chemical forms of these compounds vary markedly depending on the plant source. It is known that endive is a rich source of hydroxycinnamic acids and flavonols6-8, in particular kaempferol derivatives, but until now, the qualitative evaluation of flavonoids and phenolic acids in different commercial endive samples, commonly used as food, is far to be complete.
In this work we analyzed the methanolic extract of different commercial endive varieties largely consumed in Italian diet. The investigation was carried out using HPLC-DAD-ESI-MSn. The obtained results indicated the presence of different mono- and di-caffeoylquinic acid isomers, of cis-caftaric acid, and of different flavonol conjugates (kaempferol and quercetin derivatives)
Identification of Phenolic Constituents in Cichorium endivia Var. crispum and Var. latifolium Salads by High-Performance Liquid Chromatography with Diode Array Detection and Electrospray Ioniziation Tandem Mass Spectrometry
No full textChicory is a widely consumed vegetable and a source of phenolic compounds. Phenolic acid and flavonoid
derivatives were identified in Cichorium endivia var. crispum and var. latifolium and fully characterized using complementary
information from two different high-performance liquid chromatography detectors, diode array and mass spectrometer, in
positive and negative modes. We describe about 40 phenolic compounds, some of which have never previously been reported in
these plants, such as hydroxycinnamic acid derivatives (i.e., different mono- and dicaffeoylquinic acid isomers) and mono- and
diglycosides of quercetin, kaempferol, and myricetin (differing also by the glycosylation site). These data provide a contribution
to a more exhaustive identification of phenolic compounds in C. endivia vegetables
Effect of in vitro digestion on free α-dicarbonyl compounds in balsamic vinegars
No full textWe investigated the influence of an in vitro simulated digestion process on the content of the free α-dicarbonyl compounds most frequently found in food. A Glyoxal (GO), methylglyoxal (MGO), and diacetyl (DA) aqueous standard mixture and 2 brands of balsamic vinegar were analyzed before and after exposure to digestive enzymes. A strong matrix effect required adoption of validated RP-HPLC-DAD standard addition methods. The results showed that the digestive enzymes markedly alter the concentrations of the exogenous free α-dicarbonyl compounds ingested with food; the extent of such changes varied with the α-dicarbonyl compound itself and the diet components, which determined important but different food matrix effects also during digestion. The data also indicate that digestion can reduce the bioavailability of the toxic α-dicarbonyl compounds ingested with food. However, no firm conclusions can be drawn about a putative positive influence of digestion on the toxic potential of dietary α-dicarbonyl compounds, because their reaction in the presence of digestive enzymes likely gives rise to advanced glycation end products, which are involved in the development of chronic diseases
Isolation and identification of alfa-dicarbonyl compounds by RP-HPLC-ESI/MS in roasted barley
No full textToday barley is considered to be a minor cereal and is largely used as fodder. However, it is still important for human nutrition. In germinated form, it is the main ingredient in beer brewing. In recent years, due to its high content in beta-glucans, tocols, and polyphenols, it has been used in the preparation of functional foods. Furthermore, the secular custom in China of drinking barley or malt coffee instead of traditional coffee as a tasty beverage has greatly spread in Western regions, because the children and adults alike are highly susceptible to the negative effects of caffeine. Such beverages use roasted barley.
During roasting treatment, caramelization and the Maillard reaction occur and dicarbonyl compounds are formed as reactive intermediates.
The most extensively studied alfa-dicarbonyl compounds are methylglyoxal and glyoxal, which have attracted considerable attention as lipid peroxidation product. Glyoxal can also derive from sugar fragmentation and has been isolated in many foodstuffs such as roasted coffee and cocoa.
The toxicological profile of these compounds is not completely clear. In recent years, the interest has focused on the implications of the glycation process and the role of dietary glycation products is debated.
Various methods have been developed to determine alfa-dicarbonyl compounds. The best current assays involve derivatization of these substances with 1,2-diaminobenzene followed by quantification of the resulting quinoxaline by GC or by HPLC.
The aim of this study was to devise a method allowing simultaneous and accurate determination of alfa-dicarbonyl compounds by RP-HPLC-DAD-ESI/MS.
Eight different beverages prepared using commercial roasted conventional and organic barley samples, were tested. The applied method involved the elimination of interfering compounds by solid phase extraction (SPE), the derivatization of alfa-dicarbonyl compounds with 1,2-diaminobenzene to give quinoxaline derivatives, the purification and concentration of quinoxaline fractions by SPE, and finally RP-HPLC-DAD-ESI/MS analysis.
The obtained results indicated the presence in different amounts of glyoxal, methylglyoxal, and diacetyl in all the tested samples
Isolation and identification of alfa-dicarbonyl compounds by RP-HPLC-ESI/MS in roasted barley
No full textHPLC-DAD-ESI-MSn screening of phenolic compounds in Cichorium endivia vegetables
No full textPurpose. Polyphenols are biologically active compounds widely distributed in the plant kingdom and so present in plant-derived foods and intrinsic components of human diets. They have been shown to possess a range of biological activities that are consistent with them contributing to the protection afforded by a diet rich in fruit and vegetables against degenerative diseases (1-2). In particular, caffeic acid derivatives act as anti-inflammatory (3), skin photo damage protectors and recently chicoric acid showed anti HIV-1 activity (4-5). The levels and chemical forms of these compounds vary markedly depending on the plant source. It is known that endive is a rich source of hydroxycinnamic acids and flavonols (6-8), in particular kaempferol derivatives, but until now, the qualitative evaluation of flavonoids and phenolic acids in different commercial endive samples, commonly used as food, is far to be complete.
Methods.In this work we analyzed the methanolic extract of different commercial endive varieties largely consumed in Italian diet. The investigation was carried out using HPLC-DAD-ESI-MSn. Results. The obtained results indicated the presence of different mono- and di-caffeoylquinic acid isomers, of cis-caftaric acid, and of different flavonol conjugates (kaempferol and quercetin derivatives)
Analisi della frazione polifenolica di vegetali del genere Cichorium mediante RP-HPLC-DAD-ESI/MSn
No full textAlimenti funzionali e nutraceutici
No full textNegli ultimi decenni riguardo gli alimenti funzionali sono state formulate numerose definizioni, tuttavia a oggi non esiste una definizione ufficiale o comunemente accettata.
C’è chi ritiene che tutti gli alimenti possano in pratica essere considerati funzionali poiché ci forniscono i nutrienti e presentano pertanto effetti fisiologici. Altri ritengono che possano essere indicati come alimenti funzionali solo gli alimenti arricchiti o fortificati con un componente che presenta proprietà salutistiche. Più diffusa è l’opinione di chi considera alimenti funzionali quegli alimenti naturali o prodotti alimentari che contengono particolari componenti che producono effetti benefici sulla salute che vanno oltre i normali effetti nutrizionali.
Gli studi sugli alimenti funzionali e i nutraceutici sono iniziati quando indagini di tipo epidemiologico hanno indicato che alcune diete producono effetti positivi sulla salute delle popolazioni che le consumano, mentre altre diete provocano un aumento del rischio di sviluppare malattie croniche. Da ulteriori numerosissimi studi è emerso che le diete che hanno mostrato effetti positivi sono tutte caratterizzate da elevata presenza di frutta, verdura, legumi, cereali integrali e pesce e sono, pertanto povere in colesterolo, grassi saturi e acidi grassi trans e, diversamente, ricche di polifenoli, fibra, acidi grassi 3. Questi studi nel loro complesso hanno dimostrato che gli alimenti contengono componenti bioattivi, diversi dai nutrienti che influiscono sulla nostra salute con azione negativa o positiva e in questo caso sono definiti nutraceutici. Con tale neologismo, coniato alla fine degli anni ’80, secondo la definizione più comune, si intende indicare una sostanza che viene assunta in quanto alimento o costituente di un alimento e al tempo stesso ha effetti protettivi sulla salute e diminuisce il rischio di sviluppare malattie croniche.
Riportiamo infine la definizione per alimento funzionale formulata da FUFOSE (Functional Food Science in Europe): un alimento che influenza in modo positivo una o più funzioni dell’organismo, al di là di adeguati effetti nutrizionali, in un modo che risulta rilevante per un miglioralo stato di salute e/o benessere, e/o per una riduzione del rischio di malattia. Non è una pillola, una capsula o qualsiasi forma di supplemento dietetico. Sotto forma di dosaggio vengono, diversamente, somministrati i nutraceutici.
Tra le attività più comuni e più importanti riscontrate per questi composti vi sono: l’attività antiossidante, la capacità di modulazione degli enzimi detossificanti e del metabolismo ormonale, la proprietà di stimolare il sistema immunitario, la capacità di ridurre l’aggregazione piastrinica e la pressione sanguigna. Alcuni composti presentano inoltre attività antibatterica e altri antivirale
Derivati dell’acido idrossicinnamico nel radicchio variegate di Castelfranco
No full textTra i derivati dell’acido idrossicinnamico molto diffusi in natura sono gli esteri che si formano da uno o più residui di acidi trans-cinnamici (ad esempio acido p-cumarico, acido ferulico o acido caffeico) con l’acido chinico, composti oggetto di numerosi studi volti a definire le loro caratteristiche chimiche [1-3] e la loro attività biologica [4-7]. La loro caratterizzazione chimica negli estratti di origine vegetale risulta solitamente molto difficile sia per la presenza, in quantità spesso molto basse, di numerosi isomeri di posizione nella stessa matrice vegetale, sia per il fatto che in commercio sono disponili pochi derivati da utilizzare come standards.
Questa ricerca ha permesso di caratterizzare i derivati dell’acido idrossicinnamico presenti nel radicchio Variegato di Castelfranco, noto anche come “fiore d’inverno”, vegetale ottenuto per incrocio del Cichorium intybus var. silvestre cultivar tipica di Treviso (radicchio rosso di Treviso) e del Cichorium endivia var. latifolium (scarola). Grazie ai caratteristici patterns di frammentazione, ottenuti utilizzando la cromatografia liquida accoppiata alla spettrometria di massa (HPLC-MSn), è stato possibile mettere in evidenza la presenza nel vegetale dei diversi isomeri di posizione dei mono-acil e dei di-acil derivati dell’acido clorogenico (acidi dicaffeoilchinici, acidi caffeoil-feruloilchinici, acidi p-cumaroil-caffeoilchinici
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