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We 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. [ABSTRACT FROM AUTHOR]

Caries is the most common oral infectious disease in the world. Its development is influenced also by diet components that interfere with pathogen mutans group Streptococci (MGS) activity. A very active research to identify functional foods and their components that are generally recognised as safe has been ongoing, with the aim of developing alternative approaches, to the use of synthetic chlorhexidine, and at the reduction or prevention of caries. Until now convincing evidence exists only for green tea as a functional food for oral health, partly owing to its high content of catechins, especially epigallocatechin-gallate. A number of other foods showed potential anticaries activity. Some other foods able to act against MGS growth and/or their virulence factors in in vitro tests are: apple, red grape seeds, red wine (proanthocyanidins), nutmeg (macelignan), ajowan caraway (nafthalen-derivative), coffee (trigonelline, nicotinic and chlorogenic acids, melanoidins), barley coffee (melanoidins), chicory and mushroom (quinic acid). In vivo anticaries activity has been shown by cranberry (procyanidins), glycyrrhiza root (glycyrrhizol-A), myrtus ethanolic extract, garlic aqueous extract, cocoa extracts (procyanidins), and propolis (apigenin, tt-farnesol). [Copyright &y& Elsevier]

This paper reports the content in macronutrients, free sugars, polyphenols, and inorganic ions, known to exert any positive or negative action on microbial oral disease such as caries and gingivitis, of seven food/beverages (red chicory, mushroom, raspberry, green and black tea, cranberry juice, dark beer). Tea leaves resulted the richestmaterial in all the detected ions, anyway tea beverages resulted the richest just in fluoride. The highest content in zinc was in chicory, raspberry and mushroom. Raspberry is the richest food in strontium and boron, beer in selenium, raspberry and mushroom in copper. Beer, cranberry juice and, especially green and black tea are very rich in polyphenols, confirming these beverages as important sources of such healthy substances. The fractionation, carried out on the basis of the molecular mass (MM), of the water soluble components occurring in raspberry, chicory, and mushroom extracts (which in microbiological assays revealed the highest potential action against oral pathogens), showed that both the high and lowMM fractions are active, with the lowMM fractions displaying the highest potential action for all the fractionated extracts. Our findings show that more compounds that can play a different active role occur in these foods. [ABSTRACT FROM AUTHOR]

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]

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. [ABSTRACT FROM AUTHOR]

The anti- and pro-oxidant activity of water soluble components in Cichorium intybus var. silvestre was investigated. This vegetable is domestically known as Treviso red chicory recalling its cultivation in the area of Treviso (Italy). The vegetable juices, obtained by centrifugation of the vegetable and treated at 2 and 102 °C, were assessed for their antioxidant activity (AA) using the micellar model system linoleic acid–β-carotene. The obtained juice at 2 °C possessed either anti- or pro-oxidant activity. The boiled juice showed only strong AA, proving that the vegetable pro-oxidant components were thermally instable. Juice components were fractionated by sequential dialysis (1000–300 000 Da membrane cut-off), SPE, GFC, and RP-HPLC techniques showing the presence of several highly antioxidant components with different molecular weight (MW), and polar features in Treviso red chicory. The pro-oxidant fraction capable of masking the presence of the antioxidant components in the vegetable juice is retained by a MW>300 000 Da dialysis membrane. [Copyright &y& Elsevier]

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]

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. [ABSTRACT FROM AUTHOR]

Abstract: Red wine is a widely consumed beverage with multiple beneficial effects on human health. In the present paper, the anticaries properties of red wine were studied in vitro and ex vivo. Our in vitro findings shows that dealcoholised red wine, besides exerting antibacterial activity, strongly interferes with Streptococcus mutans adhesion to saliva-coated hydroxyapatite (sHA) beads, promotes its detachment from sHA, and powerfully inhibits in vitro biofilm formation. The main components responsible for such activities were found to be proanthocyanidins. The ability of red wine to inhibit ex vivo S. mutans biofilm formation on the occlusal surface of natural human teeth also was demonstrated. Our data indicates that protection of the oral cavity from the cariogenic action of S. mutans may be another beneficial effect of the moderate consumption of red wine. [Copyright &y& Elsevier]

Chicory 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.

In previous studies we demonstrated that green and roasted coffee contains low molecular weight (LMW) compounds capable of inhibiting the ability of Streptococcus mutans, the major causative agent of human dental caries, to adhere to hydroxyapatite (HA) beads. This study addressed the ability of the whole high molecular weight coffee fraction (cHMW) and of its melanoidin and non-melanoidin components (GFC1-5), applied at concentrations that occur in coffee beverages, to (i) inhibit S. mutans growth; (ii) affect S. mutans sucrose-dependent adhesion to and detachment from saliva-coated HA beads (sHA); and (iii) inhibit biofilm development on microtiter plates. The results indicated that only cHMW is endowed with antimicrobial activity. The cHMW fraction and each of the five GFC components inhibited S. mutans adhesion, the strongest effect being exerted by cHMW (91%) and GFC1 (88%). S. mutans detachment from sHA was four times greater (∼20%) with cHMW and the GFC1 and GFC4 melanoidins than with controls. Finally, biofilm production by S. mutans was completely abolished by cHMW and was reduced by 20% by the melanoidin components GFC2 and GFC4 and by the non-melanoidin component GFC5 compared with controls. Altogether these findings show that coffee beverage contains both LMW compounds and HMW melanoidin and non-melanoidin components with a strong ability to interfere in vitro with the S. mutans traits relevant for cariogenesis.

One of the most extensively studied and best-established properties of coffee is its antioxidant activity. We have shown that coffee brew has the ability to inhibit lipid peroxidation completely in a rat liver microsome biological system. The inhibitory activity was mainly due to the high molecular weight (HMW) fraction; this consisted of five components that were isolated, purified, and seen to occur in different amounts in the brew. Each component had different spectra and element compositions, although they all contained nitrogen. HMW, nitrogen content, and brown color enabled three components to be attributed to the melanoidin family; the two nonbrown components could not be considered as melanoidins. Each melanoidin and nonmelanoidin component contributes to a different extent to the protective action exerted by coffee brew. None of the isolated components completely inhibited microsomal lipid peroxidation alone, suggesting that each acts at different sites and/or possesses different mechanisms of action. The protective activity of coffee brew is thus underpinned by the antiradical properties, reducing power, and metal chelating ability of the individual components, each contributing to a different extent.

Coffee brew is a widely consumed beverage with multiple biological activities due both to naturally occurring components and to the hundreds of chemicals that are formed during the roasting process. Roasted coffee extract possesses antibacterial activity against a wide range of microorganisms, including Staphylococcus aureus and Streptococcus mutans, whereas green coffee extract exhibits no such activity. The naturally occurring coffee compounds, such as chlorogenic acids and caffeine, cannot therefore be responsible for the significant antibacterial activity exerted by coffee beverages against both bacteria. The very low minimum inhibitory concentration (MIC) found for standard glyoxal, methylglyoxal, and diacetyl compounds formed during the roasting process points to these alpha-dicarbonyl compounds as the main agents responsible for the antibacterial activity of brewed coffee against Sa. aureus and St. mutans. However, their low concentrations determined in the beverage account for only 50% of its antibacterial activity. The addition of caffeine, which has weak intrinsic antibacterial activity, to a mixture of alpha-dicarbonyl compounds at the concentrations found in coffee demonstrated that caffeine synergistically enhances the antibacterial activity of alpha-dicarbonyl compounds and that glyoxal, methylglyoxal, and diacetyl in the presence of caffeine account for the whole antibacterial activity of roasted coffee.

Glyoxal, methylglyoxal, and diacetyl formed as Maillard reaction products in heat-treated food were determined in coffee extracts (coffee brews) obtained from green beans and beans with different degrees of roast. The compounds have been reported to be mutagenic in vitro and genotoxic in experimental animals in a number of papers. More recently, alpha-dicarbonyl compounds have been implicated in the glycation process. Our data show that small amounts of glyoxal and methylglyoxal occur naturally in green coffee beans. Their concentrations increase in the early phases of the roasting process and then decline. Conversely, diacetyl is not found in green beans and forms later in the roasting process. Therefore, light and medium roasted coffees had the highest glyoxal and methylglyoxal content, whereas dark roasted coffee contained smaller amounts of glyoxal, methylglyoxal, and diacetyl. For the determination of coffee alpha-dicarbonyl compounds, a reversed-phase high performance liquid chromatography with a diode array detector (RP-HPLC-DAD) method was devised that involved the elimination of interfering compounds, such as chlorogenic acids, by solid phase extraction (SPE) and their derivatization with 1,2-diaminobenzene to give quinoxaline derivatives. Checks of SPE and derivatization conditions to verify recovery and yield, respectively, resulted in rates of 100%. The results of the validation procedure showed that the proposed method is selective, precise, accurate, and sensitive.

Wine contains a number of biologically active compounds with beneficial effects on human health. The antibacterial action of commercial red and white wines against oral streptococci responsible for caries development and against S. pyogenes responsible for pharyngitis was studied. Its postcontact effect against S. mutans was also studied. Both wines displayed activity. The compounds responsible for such activities were succinic, malic, lactic, tartaric, citric, and acetic acid. The synthetic mixtures of the organic acids tested at the concentrations found in wine had greater antibacterial activity than the beverages, indicating that in wine they are inhibited by other components. Wine polyphenols displayed no activity against oral streptococci or S. pyogenes. Findings show that wine is active against oral streptococci and S. pyogenes and suggest that it enhances oral health.

Some beverages and foods protect tooth surfaces against Streptococcus mutans colonization. Adhesion of S. mutans is a crucial step in the initiation and development of dental caries. In this study, we showed that barley coffee (BC), a beverage made from roasted barley, interferes with S. mutans adsorption to hydroxyapatite (HA), and we identified its antiadhesive components. The effects of sublethal concentrations (sub-MICs) of BC on the adhesion of S. mutans to saliva-coated HA beads were assessed using three experimental approaches: (A) Beads were pretreated with BC before adding bacteria, (B) BC and bacteria were added to the beads simultaneously, and (C) streptococci grown in the presence of sub-MICs of BC were added to the beads. All treatments induced variable but significant inhibition of S. mutans sucrose-dependent and -independent adherence to HA. Similar results were obtained with other oral streptococci. BC components were fractioned by dialysis and gel filtration chromatography; the <1000 Da molecular mass (MM) fraction, which contains polyphenols, zinc, and fluoride ions, and the >1000 kDa MM fraction, which consists of a potent brown antioxidant, melanoidin, both displayed antiadhesive properties. High-MM melanoidin was not detected in unroasted barley, indicating that it forms during the roasting process. Results suggest that BC consumption may influence the colonization of tooth surfaces by cariogenic bacteria.

The antiradical properties of water-soluble components of both natural and roasted barley were determined in vitro, by means of DPPH* assay and the linoleic acid-beta-carotene system, and ex vivo, in rat liver hepatocyte microsomes against lipid peroxidation induced by CCl4. The results show the occurrence in natural barley of weak antioxidant components. These are able to react against low reactive peroxyl radicals, but offer little protection against stable DPPH radicals deriving from peroxidation in microsomal lipids. Conversely, roasted barley yielded strong antioxidant components that are able to efficiently scavenge free radicals in any system used. The results show that the barley grain roasting process induces the formation of soluble Maillard reaction products with powerful antiradical activity. From roasted barley solution (barley coffee) was isolated a brown high molecular mass melanoidinic component, resistant to acidic hydrolysis, that is responsible for most of the barley coffee antioxidant activity in the biosystem.

A water-soluble lipoxygenase enzyme (EC 1.13.11.12; LOX) occurring in the red cultivar produced in the geographical area of Chioggia (Italy) of Cichorium intybus var. silvestre was isolated and characterized. The molecular mass of the enzyme was estimated to be 74,000 Da by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography. The isoelectric point was pH 6.85. The optimum values of pH, ionic strength, and temperature, shown by isoresponse surface calculated by a randomized multilevel factorial design, were 7.58, 30 mM, and 38.5 degrees C, respectively. The enzyme showed high specificity toward linoleic acid, and the study of the variation of linoleic acid concentration between 30 and 300 microM, in the presence of Tween 20 at a concentration lower than the critical micelle concentration (0.01 v/v), resulted in a typical Michaelis-Mentem curve with KM and Vmax values of 1.49 x 10(-4) M and 2.049 microM min(-1) mg(-1), respectively. The biochemical properties, the kinetic parameters found, and the carotene-bleaching activity shown in aerobic conditions seem to indicate that the isolated enzyme is a lipoxygenase type III according to the indications given for soybean isoenzymes.

The specific antiradical activity against the hydroxyl radical of the water soluble components in green and dark roasted Coffea arabica and Coffea robusta coffee samples, both in vitro by the chemical deoxiribose assay and ex vivo in a biological cellular system (IMR32 cells), were determined. All the tested coffee solutions showed remarkable antiradical activity. In the deoxiribose assay, all the tested solutions showed similar inhibitory activity (IA%) against the sugar degradation (IA values ranged from 45.2 to 46.9%). In the cell cultures, the survival increase (SI%) ranged from 197.0 to 394.0% with C. robusta roasted coffee being significantly more active than the other samples. The coffee solutions underwent dialysis (3500 Da cutoff membrane) to fraction their components. In both systems, the dialysates (MW < 3500 Da) either from green or roasted coffee, showed antiradical activity, while the only retentates (MW > 3500 Da) from the roasted coffee samples were active. The preparative gel-filtration chromatography of roasted coffee C. robusta dialysate gave three fractions active in the biological system, all containing chlorogenic acid derivatives. The most active fraction was found to be that containing the 5-O-caffeoilquinic acid, which shows a linear relation dose-response ranging from 0.02 to 0.10 mM. The results show that both green and roasted coffee possess antiradical activity, that their more active component is 5-O-caffeoyl-quinic acid, and moreover that roasting process induces high MW components (later Maillard reaction products, i.e., melanoidins), also possessing antiradical activity in coffee. These results could explain the neuroprotective effects found for coffee consumption in recent epidemiological studies.

Both the pro- and antiradical water soluble activity, toward DPPH(*), ROO(*), OH(*) radicals found in seven diet vegetables belonging to the Cichorium genus, and the effects of boiling, freezing, and freeze-drying on such activities were investigated. The vegetables were three red cultivars of Cichorium intybus var. silvestre from three different areas of production, that is, chicory from Chioggia, Treviso, and Verona, C. intybus var. foliosum (Belgian chicory), C. endivia var. latifolium (escarole), C. endiviavar. crispum ("crispa"), and a hybrid vegetable obtained by the cross between C. intybus var. silvestre and C. endivia var. latifolium (chicory from Castelfranco). The juices obtained by simple centrifugation of vegetables operating at 2 or 25 degrees C and submitted to the thermal technological treatments were assessed for antiradical activity using the DPPH(*) assay, the linoleic acid-beta-carotene system, and the deoxyribose assay. In all three assays used, each vegetable juice was shown to possess antiradical activity; there was a significant level in the C. endivia and the Belgian chicories and higher levels in the red C. intybus vegetables and the hybrid vegetable. All juice behaviors in the linoleic acid-beta-carotene system indicate that they also contain a thermally unstable component, which in a cold medium promptly promoted and accelerated linoleic acid peroxidation, therefore masking the presence of any thermally stable antiperoxyl radical components. The presence of these components, which efficiently protect linoleic acid from peroxidation, can be singled out only after inactivation by heating, or separation by dialysis, of the pro-oxidant components. Dialysis fractions showed that the pro-oxidant component has MW > 50000 Da and that the juices contain a number of antioxidant components which contribute to their antiradical activity.

The antiradical activity of water-soluble components contained in mushrooms (Psalliota campestris), onions (Allium cepa), white cabbage (Brassica oleracea var. alba), and yellow bell peppers (Capsicum annuum) against hydroxyl radicals was tested in a chemical and biological system. The vegetable juices were obtained by centrifugation of a vegetable homogenate processed at 2 degrees C or heated at 102 degrees C. The chemical system consisted of a buffered reaction mixture composed of Fe(III)-EDTA, 2-deoxy-D-ribose, ascorbic acid, and H(2)O(2) generating the hydroxyl radical. The antiradical activity was expressed as an inhibition of deoxyribose degradation. The biological system consisted of IMR32 neuroblastoma cells exposed to H(2)O(2) in the presence or absence of the vegetable juices. Cells were pretreated for either 24 h or 1 h with the vegetable juices, and reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was used as a cell viability assay. All vegetable juices inhibited the degradation of deoxyribose and increased the viability of H(2)O(2) treated cells. Raw mushroom juice proved to be the most active in both cases. Boiling significantly affected the activity of mushroom juice, but did not change significantly the effect on onions and yellow bell peppers, and partially increased the activity of white cabbage juice. Mushroom antiradical activity was also confirmed by a cytofluorimetric analysis.

Green and roasted coffees of the two most used species, Coffea arabica and Coffea robusta, several commercial coffee samples, and known coffee components were analyzed for their ability to interfere with Streptococcus mutans' sucrose-independent adsorption to saliva-coated hydroxyapatite (HA) beads. All coffee solutions showed high antiadhesive properties. The inhibition of S. mutans' adsorption to HA beads was observed both when coffee was present in the adsorption mixture and when it was used to pretreat the beads, suggesting that coffee active molecules may adsorb to a host surface, preventing the tooth receptor from interacting with any bacterial adhesions. Among the known tested coffee components, trigonelline and nicotinic and chlorogenic acids have been shown to be very active. Dialysis separation of roasted coffee components also showed that a coffee component fraction with 1000 Da < MW < 3500 Da, commonly considered as low MW coffee melanoidins, may sensibly contribute to the roasted coffee's antiadhesive properties. The obtained results showed that all coffee solutions have antiadhesive properties, which are due to both naturally occurring and roasting-induced molecules.