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PubMedDate not supplied

Mass spectrometry in grape and wine chemistry. Part I: polyphenols.

Mass spectrometry, had and still has, a very important role for research and quality control in the viticulture and enology field, and its analytical power is relevant for structural studies on aroma and polyphenolic compounds. Polyphenols are responsible for the taste and color of wine, and confer astringency and structure to the beverage. The knowledge of the anthocyanic structure is very important to predict the aging attitude of wine, and to attempt to resolve problems about color stability. Moreover, polyphenols are the main compounds related to the benefits of wine consumption in the diet, because of their properties in the treatment of circulatory disorders such as capillary fragility, peripheral chronic venous insufficiency, and microangiopathy of the retina. Liquid Chromatography-Mass Spectrometry (LC-MS) techniques are nowadays the best analytical approach to study polyphenols in grape extracts and wine, and are the most effective tool in the study of the structure of anthocyanins. The MS/MS approach is a very powerful tool that permits anthocyanin aglycone and sugar moiety characterization. LC-MS allows the characterization of complex structures of grape polyphenols, such as procyanidins, proanthocyanidins, prodelphinidins, and tannins, and provides experimental evidence for structures that were previously only hypothesized. The matrix-assisted-laser-desorption-ionization-time-of-flight (MALDI-TOF) technique is suitable to determine the presence of molecules of higher molecular weight with high accuracy, and it has been applied with success to study procyanidin oligomers up to heptamers in the reflectron mode, and up to nonamers in the linear mode. The levels of resveratrol in wine, an important polyphenol well-known for its beneficial effects, have been determined by SPME and LC-MS, and the former approach led to the best results in terms of sensitivity.

Agriculture↗
PubMedDate not supplied

Mass spectrometry in grape and wine chemistry. Part II: The consumer protection.

Controls in food industry are fundamental to protect the consumer health. For products of high quality, warranty of origin and identity is required and analytical control is very important to prevent frauds. In this article, the "state of art" of mass spectrometry in enological chemistry as a consumer safety contribute is reported. Gas chromatography-mass spectrometry (GC/MS) and liquid-chromatography-mass spectrometry (LC/MS) methods have been developed to determine pesticides, ethyl carbamate, and compounds from the yeast and bacterial metabolism in wine. The presence of pesticides in wine is mainly linked to the use of dicarboxyimide fungicides on vineyard shortly before the harvest to prevent the Botrytis cinerea attack of grape. Pesticide residues are regulated at maximum residue limits in grape of low ppm levels, but significantly lower levels in wine have to be detected, and mass spectrometry offers effective and sensitive methods. Moreover, mass spectrometry represent an advantageous alternative to the radioactive-source-containing electron capture detector commonly used in GC analysis of pesticides. Analysis of ochratoxin A (OTA) in wine by LC/MS and multiple mass spectrometry (MS/MS) permits to confirm the toxin presence without the use of expensive immunoaffinity columns, or time and solvent consuming sample derivatization procedures. Inductively coupled plasma-mass spectrometry (ICP/MS) is used to control heavy metals contamination in wine, and to verify the wine origin and authenticity. Isotopic ratio-mass spectrometry (IRMS) is applied to reveal wine watering and sugar additions, and to determine the product origin and traceability.

Consumer Product Safety↗
PubMed2004

Antioxidant activity of plant extracts on the inhibition of citral off-odor formation.

Grape seed, pomegranate seed, green tea, and black tea extracts were used to inhibit the off-odor from citral degradation. A 0.1 M citrate buffer (pH 3), containing 100 ppm citral and 200 ppm gallic acid equivalent plant extract, was incubated at 40 degrees C. The reaction mixtures were analyzed by high-performance liquid chromatography (HPLC) at days 0, 6, 10, 13, and 16 to monitor degradation of citral and formation of alpha, p-dimethylstyrene, p-cymene-8-ol, and p-methylacetophenone. The addition of plant phenolic extracts could not inhibit citral degradation, however, all four plant extracts significantly inhibited p-methylacetophenone formation. The samples, with the addition of plant extracts, exhibited higher concentrations of alpha, p-dimethylstyrene and p-cymene-8-ol than the control. This is presumed to be due to the oxygen-scavenging effect of plant extracts blocking the pathway from p-cymene-8-ol to p-methylacetophenone. Our results suggest that these plant extracts act as general antioxidants inhibiting the generation ofp-methylacetophenone regardless of the types of water-soluble phenolic compounds existing in the plant extracts.

Acyclic Monoterpenes↗
PubMed2005

Dietary grape supplement ameliorates cerebral ischemia-induced neuronal death in gerbils.

Oxidative damage has been implicated as one of the leading causes for neuronal cell death in a number of neurodegenerative diseases including stroke. Many vegetables and fruits are enriched in polyphenolic compounds known to exhibit antioxidant properties. This study is to investigate whether dietary supplement with grape powder (GP) may offer protection against neuronal damage due to global cerebral ischemia induced to Mongolian gerbils by occlusion of the common carotid arteries, a model known to cause delayed neuronal death (DND) in the hippocampal CA1 area. Gerbils were fed either a control diet (AIN76a) or a control diet supplemented with low (5.0 g/kg diet) or high (50 g/kg diet) levels of GP for two months. Four days after ischemia/reperfusion (I/R), the extent of DND, glial cell activation, nuclear DNA oxidation, and apoptotic terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) reaction in hippocampal CA1 region were assessed. Ischemia-induced extensive DND in the CA1 region was accompanied by oxidative and fragmented DNA damage and a marked increase in reactive astrocytes and microglial cells. Dietary GP supplementation significantly protected neurons against I/R-induced DND, DNA damage, and apoptosis as well as attenuated glial cell activation. These results demonstrate that due to the antioxidant properties of polyphenols in GP, nutritional diets supplemented with grape can protect the brain against ischemic damage. The neuroprotective effects of GP supplement may have wide implication in the future for prevention/protection against other neurodegenerative damage.

Animals↗
PubMed2006

Monitoring the mycotoxins in food and their biomarkers in the Czech Republic.

Testing of the presence of toxigenic microfungi and mycotoxins in foodstuffs in the food chain is an important part of the food safety strategy in The Czech Republic. At the national level, control of their presence in the entire food chain is assured by Public Health Protection Agencies, by the Veterinary Administration and by the Czech Agriculture and Food Inspection Authority. This article summarizes surveillance activities of Public Health Protection Agencies and mycotoxins findings in dietary raw materials and foodstuffs from the 1990s to 2004 in the Czech Republic. At present, the health risk from the mycotoxins exposure from foodstuffs is assessed to be relatively low in the Czech Republic, especially as far as the foodstuffs of the Czech origin are concerned. It may result in late toxic effects (e. g., carcinogenic risk) following a single or repeated ingestion of low mycotoxins doses from foodstuffs. Nevertheless, the overall situation may change due to the globalization of the food market. In order to minimize the risk associated with mycotoxins and eliminate their impact on Czech public health, continuous monitoring of the presence of toxigenic moulds, mycotoxins, and their biomarkers is necessary, in conjunction with strict respect to European Union legislation.

Aflatoxin B1↗
PubMed1987

Mobile phospholipid signals in NMR spectra of cultured human adenocarcinoma cells.

An intense peak is visible in the phosphodiester region of the 31P NMR spectra of human colon adenocarcinoma HCT-8R cells. A signal at the same frequency, partially deriving from mobile phospholipids, is also observable in the spectra of total membranes and of perchloric acid extracts prepared from the same cells. The phosphodiester signals of glycerophosphorylcholine, glycerophosphorylethanolamine, and glycerophosphorylserine resonate at lower fields with respect to this broader peak and appear only in aged samples. Enzymatic treatments of the extracts would indicate that ribonucleic acid also contributes to the broad phosphodiester signal. Moreover, 1H NMR spectra show the presence of lipid structures, characterized by high mobility, in the cell and in the membrane samples, similar to what was already observed in other tumor cells and tissues.

Adenocarcinoma↗
PubMed1997

Hormonally induced modulation in the phosphate metabolites of breast cancer: analysis of in vivo 31P MRS signals with a modified prony method.

A modified Prony method (MPM) was applied to analyze the main signals present in spatially resolved 31P NMR spectra of MCF7 breast tumors implanted in nude mice. First, the method was tested on synthetic data to establish its limits of reliability. Its performance with respect to peak identification and quantification of signal intensities was then exploited on data from three implanted tumors during hormonal manipulation with estrogen and the antiestrogenic drug tamoxifen. The phosphomonoester peak was resolved into phosphocholine (PC) and phosphoethanolamine (PE). Treatment with tamoxifen led to a significant reduction in the PE to PE+PC peak amplitude ratio in the tumors under consideration. MPM analysis also revealed the presence of two different inorganic phosphate pools: a larger acidic pool and a smaller alkaline pool during estrogen-induced growth and the reverse during tumor regression.

Animals↗
PubMed2004

(1H) MRS studies of signals from mobile lipids and from lipid metabolites: comparison of the behavior in cultured tumor cells and in spheroids.

(1)H magnetic resonance studies on MCF-7 and HeLa cells were undertaken to reveal differences in lipid and lipid metabolite signals during the growth in culture. High intensity mobile lipid (ML) signals were found during the first days in culture, while afterwards the same signals declined and started increasing again at confluence and at late confluence. At the same time, signals from the lipid metabolite phosphocholine decreased in intensity while signals from glycerophosphocholine in MCF-7 and from choline in HeLa increased as cells approached confluence. Spectral parameters from actively proliferating and non-proliferating cells were used to classify cells with respect to the proliferative conditions by means of a multivariate statistical analysis. Furthermore, it was shown that polyunsaturation of mobile lipid chains was lower in the confluent group with respect to the actively proliferating cells. The examination of spectra from suspensions of MCF-7 spheroids with diameter smaller than 500 microm suggests that cells in spheroids are in condition of lipid metabolism similar to that of confluent cultured cells.

Algorithms↗
PubMedDate not supplied

Fractionation of grape tannins and analysis by matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry.

Polymeric tannins, extracted from grape berries (Gamay variety), were fractionated according to their mean degree of polymerisation (mDP) on a styrene-divinylbenzene phase eluted with a gradient of methanol:chloroform. Increasing the percentage of methanol led to the solubilisation of higher molecular weight tannins. The mean mDP of each collected fraction was determined by acid-catalysed degradation in the presence of a nucleophilic reagent. The fractionation method produced a linear gradient of mDP varying between 1.84 and 19.34. The fractions were partially characterised by matrix assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF/MS). The spectra showed a complex mixture of proanthocyanidins and galloylated proanthocyanidins up to 4000 amu.

Anthocyanins↗
PubMed2004

Grape berry biochemistry revisited upon proteomic analysis of the mesocarp.

Major soluble proteins of grapevine ripe berries were extracted from six different cultivars including non vinifera, with trichloroacetic acid acetone and resolved in two-dimensional electrophoresis (2-DE) gels. About three hundred spots were detected on the 2-DE map after colloidal blue staining. From 2-DE map of cv. Gamay mesocarp, 67 proteins were identified (p > 0.95) using matrix-assisted laser desorption/ionization-mass spectrometry analysis. About 34%, 19%, and 13% of identified proteins play, respectively, a role in energy metabolism, defense, and stress response and primary metabolism. 2-DE analysis revealed considerable accumulation of dehydrin, invertase, and a putative transcription factor in the ripe fruit, in addition to pathogenesis-related proteins such as chitinase and thaumatin-like proteins previously documented as prevalent proteins in ripe berries. Actual translation of redundant transcripts of unclear function such as Grip31, Grip32, and Grip61 recently cloned in ripe grape berries was confirmed. The relative abundance of UDP-glucose pyrophosphorylase and vacuolar invertase strongly supported a key role of the apoplastic pathway of sugar loading during ripening. Comparative analysis shows that differences between cultivars were low, but different isoforms of alcohol dehydrogenase and of a transcription factor of hexose transporter were obvious in the six cultivars. Peptide mass fingerprinting suggests that the Adh isoforms would be Adh2/Adh6 or Adh2/Adh7 dimers and unambiguously shows that considerable deletion/insertion inside Adh7 are not cloning artifacts.

Electrophoresis, Gel, Two-Dimensional↗
PubMed2005

Design, construction, and characterization of a large synthetic human antibody phage display library.

Advances in proteomic research allow the identification of several hundred protein components in complex biological specimens. Structural information is typically lost during proteomic investigations. For this reason, the rapid isolation of monoclonal antibodies specific to proteins of interest would allow the study of structurally intact biological specimens, thus providing complementary proteomic information. Here, we describe the design, construction, characterization, and use of a large synthetic human antibody phage display library (ETH-2-Gold) containing three billion individual antibody clones. A large repertoire of antibodies with similar biochemical properties was produced by appending short variable complementarity-determining region 3 (CDR3) onto three antibody germline segments (DP47, DPK22, and DPL16), which are frequently found in human antibodies. The ETH-2-Gold library exhibits efficient display of antibody fragments on filamentous phage, as assessed by immunoblot. Furthermore, the library is highly functional, since >90% of clones express soluble antibodies in bacteria and since good quality monoclonal antibodies have been isolated against 16 different antigens. The usefulness of the library as a tool for generating monoclonal antibodies for biomedical applications was tested using the C-domain of tenascin-C (a marker of angiogenesis) as antigen and showing that specific antibodies to this target were able to stain vascular structures in tumor sections.

Antibodies, Monoclonal↗
PubMed2005

Simazine dynamics in a vineyard soil at Casablanca valley, Chile.

Field dissipation, soil movement and laboratory leaching studies were performed to elucidate the effect of two rainfall amounts in the behaviour and environmental fate of simazine under climatic conditions at Casablanca Valley, Chile. Dissipation and soil movement were studied in a field vineyard with a sandy loam soil (Inceptisol; 74.08% sand; 14.87% silt and 11.04% clay). Simazine was applied to bare soil at 2.0 kg AI ha(-1), and its concentration was measured using immunoassay (ELISA) at 0, 10, 20, 40 and 90 days after application under two rainfall amounts, natural field conditions (39 mm) and modified conditions (39 + 180 mm). Simazine leaching was studied using soil core PVC lysimeters (0.9 m height; 0.22 m diameter). Field dissipation data were adjusted with a bi-exponential model. Half-life (DT(50)) values varied between 31.3 (+/-2.5) and 19.0 (+/-4.2) days under natural and modified conditions, respectively. Simazine K(d) varied from 0.42 to 2.15 (K(oc) 32.6-216.2) in the soil profile. Simazine was detected at a 90-cm soil depth in concentrations of 0.0085 (+/-0.0043) mg kg(-1) and 0.0321 (+/-0.001) mg kg(-1) under field and modified conditions, respectively. The maximum simazine leachate concentrations were 0.013 (+/-0.00084) mg litre(-1) (0.012% of total applied simazine) and 0.0084 (+/-0.00082) mg litre(-1) (0.11% of total applied simazine) for field and modified conditions respectively. These data indicate that water quantity has a significant effect on the DT(50) and the amount of simazine that moved through the soil profile, but not on the soil depth reached by this herbicide.

Agriculture↗
PubMed2006

Effect of dose rate and mixtures of fungicides on selection for QoI resistance in populations of Plasmopara viticola.

Resistance to QoI fungicides (strobilurins, famoxadone and fenamidone) in populations of Plasmopara viticola (Berk & Curt) Berlese & de Toni developed soon after their introduction in France and Italy. Current resistance management strategies include limitation of the number of applications, use of mixtures and alternation of fungicides with different modes of action. The selection pressure resulting from QoI fungicides applied alone or in mixtures with non-QoI fungicides was investigated in whole plant experiments under controlled conditions. QoI-resistant populations of P. viticola gradually reverted to full sensitivity following consecutive transfers to untreated plants, suggesting that resistant phenotypes were less competitive than sensitive ones. When cycled on QoI-treated plants, reduction in sensitivity was greater for the QoI fungicide which had greater intrinsic activity on P. viticola. Sensitivity decreased at each subsequent cycle, resulting in almost full resistance after four generations. Mixture experiments indicated that selection pressure was affected most by the dose of the QoI fungicide and the nature of the partner fungicide. Folpet delayed selection pressure most effectively when it was associated with famoxadone or azoxystrobin. Mancozeb was least effective at reducing the rate of selection compared with the QoI alone, and fosetyl-aluminium was intermediate. Higher rates of selection were recorded when the dose of the QoI fungicide, solo or in a mixture, was increased from 1 to 4 microg ml(-1). Increasing the dose of the non-QoI partner fungicide in the mixture from 10 to 30 microg ml(-1) resulted in reduced selection pressure. These results suggest that the choice of the fungicide partner and its dosage in the mixture can significantly affect the success of QoI resistance management strategies under practical conditions.

Drug Interactions↗
PubMed2006

In vitro selection of an effective fungicide against Armillaria mellea and control of white root rot of grapevine in the field.

Armillaria mellea (Vahl ex Fr) Kummer is an aggressive pathogen which causes white root rot in a wide range of hosts. Most chemicals tested so far against Armillaria, both in vitro and in the field, have not been effective in reducing fungal growth and/or preventing plant decline and mortality. In the present work the effects of four DMI (sterol demethylation inhibitor) fungicides, cyproconazole, hexaconazole, propiconazole and tetraconazole, and another six downwardly mobile systemic chemicals, azoxystrobin, cubiet (copper bis(ethoxy-dihydroxy-diethylamino)sulfate), fosetyl-Al, potassium phosphite, sodium tetrathiocarbonate (STTC) and 2-(thiocyanomethylthio)benzothiazole (TCMTB), on the mycelial growth of A. mellea were compared and evaluated; the product yielding the best results in in vitro experiments was selected to determine its efficacy in preventing decline and mortality of grapevines in the field. Best results on in vitro fungal growth reduction were obtained with the four azoles tested, in particular with cyproconazole and hexaconazole, achieving 67-72% mycelial growth inhibition at the lowest dose. Results obtained in the field showed that a dose of 50 mg AI litre(-1) of cyproconazole once or twice a year was efficient in controlling the disease even in vines seriously affected by the pathogen. However, further research is required to study minimum effective doses, residual effects and the convenience of the application of annual dressings in damaged vineyards, so as to gradually reduce the pathogen inoculum potential in soil and control the disease while reducing chemical residues in the plant and preventing development of fungal resistance.

Agaricales↗
PubMed2007

Assessment of QoI resistance in Plasmopara viticola oospores.

QoI fungicides, inhibitors of mitochondrial respiration at the Qo site of cytochrome b in the mitochondrial bc(1) enzyme complex, are commonly applied in vineyards against Plasmopara viticola (Berk. & MA Curtis) Berl. & De Toni. Numerous treatments per year with QoI fungicides can lead to the selection of resistant strains in the pathogen population owing to the very specific and efficient mode of action. In order to evaluate the resistance risk and its development, two different methods, biological and molecular, were applied to measure the sensitivity of oospores differentiated in vineyards, both treated and untreated with azoxystrobin, from 2000 to 2004. Assays using oospores have the advantage of analysing the sensitivity of bulked samples randomly collected in vineyards, describing accurately the status of resistance at the end of the grapevine growing season. Both methods correlated well in describing the resistance situation in vineyards. QoI resistance was not observed in one vineyard never treated with QoI fungicides. In the vineyard where azoxystrobin had been used in mixture with folpet, the selection of QoI-resistant strains was lower, compared with using solely QoI. In vineyards where QoI treatments have been stopped, a decrease in resistance was generally observed.

Biological Assay↗
PubMed2004

Oral intake of proanthocyanidin-rich extract from grape seeds improves chloasma.

Chloasma (melasma), an acquired hypermelanosis, is often recalcitrant to various treatments and an amenable, as well as safe, pigment-reducing modality is needed. We investigated that the reducing effect of proanthocyanidin, a powerful antioxidant, on chloasma in a one-year open design study. Proanthocyanidin-rich grape seed extract (GSE) was orally administered to 12 Japanese woman candidates with chloasma for 6 months between August 2001 and January 2002 and to 11 of these 12 for 5 months between March and July 2002. Clinical observation, L* value (lightening) and melanin index, and size (length and width) measurements of chloasma were performed throughout the study period. The first 6 months of GSE intake improved or slightly improved chloasma in 10 of the 12 women (83%, p < 0.01) and following 5 months of intake improved or slightly improved chloasma in 6 of the 11 candidates (54%, p < 0.01). L* values also increased after GSE intake (57.8 +/- 2.5 at the start vs 59.3 +/- 2.3 at 6 months and 58.7 +/- 2.5 at the end of study). Melanin-index significantly decreased after 6 months of the intake (0.025 +/- 0.005 at the start vs 0.019 +/- 0.004 at 6 months) (p < 0.01), and also decreased at the end of study (0.021 +/- 0.005) (p < 0.05). GSE is effective in reducing the hyperpigmentation of women with chloasma. The beneficial effects of GSE was maximally achieved after 6 months and these was no further improvement after this period. The latter GSE intake for 5 months may prevent chloasma from becoming worse prior to the summer season. GSE is safe and useful for improving chloasma.

Administration, Oral↗
PubMed2004

Protection of urinary bladder function by grape suspension.

Urinary bladder dysfunction secondary to BPH is a major affliction of aging men. A rabbit model of partial outlet obstruction was used to evaluate the ability of a standardized grape suspension to protect the bladder against obstructive bladder dysfunction.Twenty-four New Zealand White rabbits were separated into four groups of six rabbits each. Groups 1 and 3 were pretreated by oral gavage for 3 weeks with a standardized grape suspension suspended in water; groups 2 and 4 were treated with vehicle. Groups 1 and 3 received sham operations after 3 weeks of treatment; groups 2 and 4 received partial outlet obstruction by surgically placing a silk ligature loosely around the urethra. At 3 weeks following surgery, in vivo and in vitro bladder functions were evaluated. Based on both in vivo and in vitro studies, the grape suspension significantly reduced the severity of obstructed bladder dysfunction. This is consistent with the hypothesis that ischemia is a major etiological factor in obstructive dysfunction, and treatment with antioxidants and membrane stabilization compounds such as those in the grape suspension can be effective in the treatment of obstructive bladder pathology.

Adrenergic alpha-Antagonists↗
PubMed2003

Quantification of the ratio of positional isomer dilinoleoyl-oleoyl glycerols in vegetable oils.

The distribution of fatty acids in a triacylglycerol is of great importance from nutritional, biochemical, quality and technological points of view. The ratio of triacylglycerol positional isomers containing two linoleic acid (18:2) and one oleic acid (18:1) moieties--namely, 1(3),2-dilinoleoyl-3(1)-oleoyl glycerol (LLO) and 1,3-dilinoleoyl-2-oleoyl glycerol (LOL)--were quantified in grape seed, olive, pumpkin seed, soybean, sunflower and wheat germ oils by high-performance liquid chromatography/atmospheric pressure chemical ionization mass spectrometry (HPLC/APCI-MS) in selected ion monitoring (SIM) mode. Relative LOL contents (LOL/(LLO+LOL)) of the oils were calculated from the mass abundances of the [LL]+ and [LO]+ diacylglycerol fragment ions ([M+H-RCOOH]+) using a calibration curve. The calibration curve of the relative diacylglycerol mass abundances was measured in SIM mode. The relative LOL contents were found to be relatively consistent for each oil variety. The relative LOL content in grape seed, sunflower, pumpkin seed, soybean and wheat germ oils accounted for 44.2 +/- 2.6, 26.8 +/- 3.2, 16.7 +/- 4.6, 15.9 +/- 2.9 and 13.9 +/- 4.3%, respectively. Only olive oils contained practically 100% of the LLO isomer. These results indicate that the unsaturated fatty acids such as linoleic and oleic acids have 'non-random' distribution patterns in various oils.

Cucurbita↗