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Polyphenolic phytochemicals present in certain plant tissues exhibit multifunctional properties, in terms of expressing in vitroantioxidant activity. In the case of wines, which can be considered as very complex mixtures of polyphenols, a trend has been revealed by previous studies regarding the correlation of values from antioxidant tests based on different chemical backgrounds. In this respect, 25 aged red wines, along with some characteristic polyphenolic antioxidants, were employed to carry out specific antioxidant tests, including the widely used DPPH• stable radical and a ferric reducing assay. The results showed that the values arising from these two tests correlated very well (r2 0.8761) at a 99.9% significance level (p

HPLC-diode array detection-electrospray ionization mass spectrometry was used to determine qualitatively and quantitatively the flavonoid content of several fractions and residues of extracts of Greek navel sweet orange peel (Citrus sinensis) from the region of southern Greece (Leonidi-Tripoli). The main groups of flavonoids found according to HPLC retention times, spectral data and literature references were polymethoxylated flavones, C-glycosylated flavones, O-glycosylated flavones, O-glycosylated flavanones, flavonols and phenolic acids and their derivatives. The ethyl acetate fraction which has been shown in previous work to possess the best radical scavenging activity among the others was found to contain C-glycosylated flavones, polymethoxylated flavones, O-glycosylated flavones, O-glycosylated flavanones, two phenolic acid derivatives and two unknown compounds, all in low concentrations. The group of C-glycosylated flavones was reported for the first time in the peel of Navel sweet orange. The C-glycosylated flavones found according to their spectral characteristics and literature were 6-C-beta-glucosyldiosmin, 6,8-di-C-glucopyranosylapigenin, 6,8-di-C-beta-glucosyldiosmin and two unknown. The results suggest that the ethyl acetate fraction of navel Citrus sinensis peel consists of significant antioxidant compounds and can be used as a food additive of natural origin or a pharmaceutical supplement using as a source of peel the byproducts of the orange juice industry.

Tea and herbal infusions have been studied for their polyphenolic content, antioxidant activity and phenolic profile. The total phenolics recovered by ethyl acetate from the water extract, were determined by the Folin–Ciocalteu procedure and ranged from 88.1 ± 0.42 (Greek mountain tea) to 1216 ± 32.0 mg (Chinese green tea) GAE (Gallic acid equivalents)/cup. The antioxidant activity was evaluated by two methods, DPPH and chemiluminescence assays, using Trolox and quercetin as standards. The EC 50 of herbal extracts ranged from 0.151 ± 0.002 mg extract/mg DPPH (0.38 quercetin equivalents and 0.57 Trolox equivalents), for Chinese green tea, to 0.77 ± 0.012 mg extract/mg DPPH (0.08 quercetin equivalents and 0.13 Trolox equivalents), for Greek mountain tea. Chemiluminescence assay results showed that the IC 50 ranged from 0.17 ± 3.4 × 10 −3 μg extract/ml of the final solution in the measuring cell (1.89 quercetin and 5.89 Trolox equivalents) for Chinese green tea, to 1.10 ± 1.86 × 10 −2 g extract/ml of the final solution in the measuring cell (0.29 quercetin and 0.90 Trolox equivalents) for Greek mountain tea. The phenolic profile in the herbal infusions was investigated by LC-DAD-MS in the positive electrospray ionization (ESI + ) mode. About 60 different flavonoids, phenolic acids and their derivatives have been identified.

Ethyl acetate extracts of seeds originating from nine Hellenic native and international Vitis vinifera varieties cultivated in Greece were screened for their contents of characteristic polyphenols. The compounds determined were principal constituents of low molecular weight, including gallic acid (GA), catechin (CT), epicatechin (ECT), epigallocatechin (EGC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG), and the procyanidins B 1 and B 2 (dimers). Total content varied from 55.1 to 964 mg per 100 g of seeds, the average being 380 mg per 100 g. The most abundant polyphenol was CT, accounting for 49.8% of the total content, followed by ECT (26.0%), ECG (9.3%), procyanidin B 1 (5.8%), and procyanidin B 2 (5.1%), whereas EGC and GA were minor constituents. The assessment of the in vitro antiradical activity ( A AR ), employing the stable radical DPPH , showed that there is a significant correlation with total polyphenol content ( r 2 =0.6499, P 1 may be one of the most important radical scavengers in grape seed extracts ( r 2 =0.7934, P

Browning is a serious problem in relation to white wine quality and mostly affects the sensory attributes, whereas its impact on the dietary value of wines has never been investigated. Browning, however, is well known to be associated with polyphenol oxidation, and therefore it may be accompanied by changes in the antioxidant capacity. On the basis of this consideration, experimental white wines vinified and stored under identical conditions were subjected to accelerated browning, and efforts were made to distinguish compositional parameters that might be related to the extent of browning development. Further, the consequences of browning on the reducing power and antiradical activity were assessed. It was shown that none of the parameters examined (titratable acidity, pH, total SO2, total polyphenols and total flavanols) play an important role in browning onset, but SO2 appeared to exert a statistically significant influence (r2=0.6394, P

Livia PERSANO ODDOa*, Roberto PIROb with the collaboration of: Etienne BRUNEAU, Christine GUYOT-DECLERCK (Belgium); Tzeko IVANOV (Bulgaria); Ji ina PISKULOVA (Czech Republic); Christian FLAMINI, Joel LHERITIER, Monique MORLOT (France); Harald RUSSMANN, Werner VON DER OHE, Katharine Von der OHE (Germany); Panagiota GOTSIOU, Sophia KARABOURNIOTI, Panagiotis KEFALAS, Maria PASSALOGLOU-KATRALI, Andreas THRASYVOULOU, Angeliki TSIGOURI (Greece); Gian Luigi MARCAZZAN, Maria Lucia PIANA, Maria Gioia PIAZZA, Anna Gloria SABATINI (Italy); Jacob KERKVLIET (Netherlands); Joana GODINHO (Portugal); Antonio BENTABOL, Alberto ORTIZ VALBUENA (Spain), Stefan BOGDANOV, Kaspar RUOFF (Switzerland)

The possibility of utilising chopped and deseeded carob pods (kibbles) as a source of polyphenolic antioxidants was examined by performing extractions with various solvent systems, in order to evaluate and optimize the conditions for the recovery of polyphenols. Maximum quantities of polyphenolic components were found in 80 % acetone extracts, as evaluated by measuring total polyphenol and total flavanol content. By contrast, ethyl acetate was inefficient in extracting polyphenols. The assessment of the antioxidant potency of carob pod extracts employing two characteristic in vitro models showed that carobs contain polyphenols with appreciable antiradical and reducing properties. The values obtained were compared to the data on red wines and pure polyphenolic antioxidants.

The antiradical and hydroxyl free radical scavenging activities were estimated in twenty-five, aged red wines from different areas in Greece. The antiradical activity (AAR) was determined by means of the wellknown DPPH• method, and its values ranged from 24.7 to 125.1. A novel, chemiluminescence-based, highly sensitive assay was applied for determination of the hydroxyl free radical scavenging activity (SAHFR), which varied from 1.62 to 12.22 mM quercetin equivalents. The values from the two assays correlated very well (r2 =0.8542, PHFR and AAR. This tendency in aged red wines, which may be significant in evaluating the antioxidant behaviour of red wine polyphenols, is discussed on the basis of previous research and relevant data.

14 pages, 7 figures, 3 tables., Kinetic studies on thermal stability of anthocyanins isolated from the dry calyces of Hibiscus sabdariffa L. (roselle) were carried out in aqueous solutions (55–98 °C), either as free or copigmented anthocyanins with chlorogenic acid, and in the dry state as free anthocyanins or co-lyophilized with an amorphous polysaccharide (pullulan) and stored in different relative humidity environments (water activities 0.33, 0.53, 0.75 and 0.84) at 40 °C. The rate constants for degradation were obtained from first-order reaction kinetic plots. The degradation kinetics of individual anthocyanin components in solution, as assessed by HPLC, followed an Arrhenius-type response with respect to temperature; activation energies, Ea, varied between 13.3 and 15.1 kcal/mol. Copigmentation of anthocyanins with chlorogenic acid did not seem to improve their stability in solution. In the dry state, the degradation rate constants increased with the water activity, particularly above 0.53. In the freeze-dried pullulan–anthocyanin mixtures, the polysaccharide matrix delayed colour degradation compared to the free anthocyanin preparations by 1.5–1.8 times. The degradation kinetics of anthocyanins did not show any dependence on the molecular mobility of the system, as it relates to the glass–rubber transition (Tg) detectable by calorimetry. Anthocyanin degradation occurred, even at sub-Tg temperatures of the amorphous matrices, whereas no changes in the rate constants were observed in the vicinity of the glass transition; the plot of (lnk)−1 against (T−Tg) was linear with all data fitting into a common line as predicted by the Williams–Landel–Ferry (WLF) equation. Both free and co-lyophilized with pullulan Hibiscus anthocyanins exhibited good antiradical activity throughout storage in all humidity environments studied, despite of a substantial loss in colour intensity., G.G. acknowledges the receipt of a fellowship from MAICh during her MSc studies. This project has been partially supported from the GreekM inistry of Industry, Energy and Technology and the Spanish Ministerio de Asuntos Exteriores through a grant of bilateral cooperation between Greece and Spain.

Polyphenolic substances are of profound significance to both the technological and nutritional value of grapes (Vitis vinifera sp.) and wines. The Hellenic vineyard embraces a large number of native V. vinifera species which have a peculiar polyphenolic composition, as illustrated by a number of recent research works. For this reason it was deemed necessary to gather the bibliographical data that have been published so far, in order to provide a complete insight into the polyphenolic composition of Hellenic wines, with a view to it being a first step towards the creation of a database which might be of assistance in epidemiological research. Emphasis has also been given to some data that revealed valuable information on variety-related patterns for major phenolics in wines made from single, autochthonous cultivars.

Twenty-six white wines of “Appellation of Origin of High Quality”, covering all viticultural areas of Greece were assayed for their polyphenolic content, using high-performance liquid chromatography coupled with diode array detector. Further, the antiradical activity and reducing power of the wines were evaluated. In both cases, the antioxidant potency of the wines was correlated with the total polyphenol concentration, as well as with the concentration of the two major classes of white wine polyphenols, hydroxycinnamates and flavanols. It was found that wines contain in average 324.7 mg l −1 total hydroxycinnamates (THC) and 52.2 mg l −1 total non-hydroxycinnamates (TNHC), (catechin, epicatechin, gallic acid). The antiradical activity was correlated principally with total phenols (THC+TNHC) and with THC, but poorly with TNHC. By contrast, TNHC were found to exert sound reducing effect, as opposed to THC which were weakly correlated with the reducing power.

Selected Greek regional, aged red wines were assessed for their polyphenolic composition using well-established spectrophotometric methodology, and tested for antioxidant potential by three different assays. The total polyphenol (TP) concentration was found to vary from 1217 to 3772 mg L −1 gallic acid equivalents, total anthocyanin (TA) content ranged from 44.3 to 360.1 mg L −1 , and total flavanol (TF) from 291.1 to 664.8 mg L −1 catechin equivalents. The antiradical activity was evaluated using DPPH • , and varied from 0.73 to 1.37 m M Trolox® equivalents, while reducing power values were from 5.29 to 10.80 m M ascorbic acid equivalents, using a modified FRAP assay. The hydroxyl free radical scavenging activity was determined with the deoxyribose method, and ranged from 38.5 to 59.9% decrease in A 532 relative to control. The examinations showed that TP and TF may provide a significant contribution to the overall antioxidant status of wines, but TA appears to be a less important factor in this respect. Reducing power was found to be highly associated with the antiradical activity of wines.

The effect of irrigation and harvest time was studied with respect to almond kernel quality with two almond cultivars. Kernel quality analyses included kernel weight, moisture content, kernel oil quality and composition, and sugar content and composition. ‘Ferragnes’ kernels had similar oil content and quality but higher oleic acid content than ‘Texas’ almonds. Various differences were also found in sugar content and composition between the two cultivars. Irrigation delayed almond maturation, had no effect on oil and sugar content, but improved oil composition with higher oleic acid content and sugar composition with higher sucrose content compared to dry-grown almonds. Late harvested almonds contained more dry matter per kernel, higher oil content but of lower quality, based on the UV absorption coefficients and oil composition, and higher sugar content mainly due to further sucrose accumulation compared to early harvested almonds.

A simple, rapid, sensitive, and enzyme-free analytical method for estimating scavenging of hydrogen peroxide (H2O2) was developed.Peroxyoxalate chemiluminescence (POCL) was measured, using 9,10-diphenylanthracene as fluorophore.The chemiluminescence signal was found to be linear in response to increasing amounts of H2O2 in ethyl acetate/acetonitrile (9:1) (r2 = .9990), within a range of concentrations varying from 9.0 to 72.0 microM. In contrast, acetonitrile was highly unsuitable because of poor linearity (r2 = .3736) and poor signal stability. The linearity of POCL inhibition, as a measure of H2O2 scavenging, was tested employing well-known, lipid-soluble antioxidants, including beta-carotene, butylated hydroxytoluene (BHT) and alpha-tocopherol, and also the more polar flavonol quercetin, and the water-soluble L-ascorbic acid (AA). Under the experimental conditions, the corresponding values of H2O2 scavenging activity (SA(HP)) for quercetin, beta-carotene, alpha-tocopherol, and L-AA were 19.1 +/- 0.4, 70.9 +/- 20.1, 8.4 +/- 0.4, and 44.8 +/- 5.6 x 10(-3) microM(-1)The data establish the assay as a method for assessing the H2O2 quenching activity of lipid-soluble antioxidants.

A general and convenient synthesis of beta-ketols and alpha,beta-alkenones has been achieved by a Knoevenagel condensation of a beta-ketoacid with an aldehyde in aqueous medium. Saponification of a beta-ketoester by an aqueous KOH 10% solution gives the potassium salt of the beta-ketoacid, which is condensed in situ with an aldehyde at pH 7.8-8.0, at 60 degrees C for 5-6 h. The intermediate beta-ketocarboxylate is smoothly decarboxylated in the reaction medium, giving the beta-ketol in high yield (75-90%). Acidification of the reaction mixture at pH 1 and heating at 70 degrees C under vigorous stirring for 6 h, leads directly to the corresponding alpha,beta-unsaturated ketone in good yield (65-75%).

Twenty-seven Greek aged red wines were evaluated for their colour characteristics using well-established spectrophotometric methodology. Further, the analytical anthocyanin composition was assayed employing reversed-phase high performance liquid chromatography HPLC with diode array detection (HPLC-DAD). As additional parameters for the interpretation of differences observed between wines, the total phenol (TP) and total flavanol (TF) contents were also determined. Total anthocyanin (TA) content varied from 44.3 mg l -1 to 363.1 mg l -1 as determined spectrophotometrically, whereas the HPLC analyses showed that monomeric anthocyanin content was from 0.0 mg l -1 to 203.8 mg l -1 . Coloured (ionised) anthocyanin content ranged from 2.3 mg l -1 to 37.2 mg l -1 . On average, 9.7% of the anthocyanins were found to be co-pigmented and 66.4% polymerised. In addition, it was observed that the chemical age of the wines was correlated with - log(TA HPLC /TP) but less so with - log(TA HPLC /TF).

The total hydroxycinnamate (THC) and total flavanol (TF) contents were determined in 26 selected Greek white wines of 'Appellation of Origin of High Quality' using well-established spectrophotometric methodology. Furthermore, two parameters related to the antioxidant capacity of wines, the antiradical activity (A AR ) and the reducing power (P R ), were also determined using the stable DPPH radical and a ferric reducing power assay respectively. THC content varied from 64.4 to 197.1 mg l 1 chlorogenic acid equivalents (CGAE), whereas TF content exhibited larger variation, ranging from 3.3 to 205.3mg l 1 catechin equivalents (CTE). A AR and P R were found to range from 0.47 to 0.60mM Trolox equivalents (TRE) and from 0.32 to 2.05 mM quercetin equivalents (QE) respectively. Regression analysis at 95% significance level indicated that reducing effects are likely to be exerted by the flavanol fraction (SF Cette etude evalue la composition en polyphenols de 26 vins blancs grecs et examine la relation entre les 2 classes principales de polyphenols, les hydroxycinnamates et les flavonols, et les proprietes antiradicalaires et reductrices des vins blancs. Les resultats indiquent que le pouvoir reducteur est plutot relie a la fraction flavonol alors que l'activite antiradicalaire serait influencee par la somme des teneurs en hydroxycinnamates et flavonols.

Extracts from three Origanum species, including Origanum microphyllum, Origanum dictamnus and Origanum vulgare subsp. hirtum, native to the island of Crete (southern Greece), were partly fractionated through successive partition with ethyl acetate and n-butanol. All the fractions obtained were profiled with regard to their major polyphenolic constituents, using liquid chromatography-diode array-mass spectrometry. Furthermore, the antioxidant potency of each fraction was assessed by estimating the antiradical activity (A(AR)) and the hydroxyl free radical scavenging activity (SA(HFR)). The chromatographic analyses revealed a rich profile mainly for the ethyl acetate fractions, composed principally by flavones, which were accompanied by a limited number of phenylpropanoids, flavanones and dihydroflavonols. The highest values of antioxidant activity were displayed by the ethyl acetate extract of O. dictamnus, which also possessed the richest polyphenolic composition.

mRNA from human polymorphonuclear neutrophil leucocytes (PMNs) was probed with cDNA encoding human skeletal muscle arginine-specific ADP-ribosyltransferase (ART1). A single 2.6-kb transcript was identified, which was similar in size to that observed in human skeletal muscle RNA. An 872-bp cDNA fragment, corresponding to the amino acid sequence of the processed human skeletal muscle enzyme, was generated by reverse transcription–PCR amplification of RNA from human PMNs, and was found to be identical to the ART1 cDNA derived from human skeletal muscle. ART1 was expressed as a fusion protein with glutathione S-transferase (GST) in insect cells, and antibodies were raised against the fusion protein in a rabbit. Following removal of GST immunoreactivity by immunoprecipitation, these antibodies were used to measure the abundance of immunoreactive ART1 on the surface of PMNs. Exposure of PMNs to formyl-Met-Leu-Phe (FMLP) was followed by a rapid increase in the abundance of cell surface ART1 (T1/2 = 1.9 min), and the concentration of FMLP for half-maximum response was 28.6 n m. Similar responses were observed after exposure of the cells to platelet-activating factor or interleukin-8, and we conclude that some of the effects of these chemotaxins are mediated by translocation of an intracellular pool of ART1 to its site of catalytic activity on the outer aspect of the plasma membrane.

A rapid and sensitive method has been developed for the determination of trans -resveratrol in wine. This method consists of a solid phase extraction step followed by a rapid HPLC quantification step (30 min). The improvement of this method consists of the washing step of the solid phase extraction method carried out at pH 8.0 (12% ethanol in a phosphate buffer solution), thus permitting a more efficient removal of the interfering phenolic compounds in conjunction with the required low volume of tested sample. Trans -resveratrol content was determined for 29 red Greek wines of appellation of origin. The concentrations found varied between 0.550 and 2.534 mg/l. The wines produced by grape varieties grown in the Greek islands (Rhodes, Crete and Paros) were richer in trans -resveratrol. The grape variety Mandilaria, in particular, was the Greek variety with the highest trans -resveratrol content.

Wine is one of the most important products of Greece and other Mediterranean countries. Adulteration of wines, either in terms of geographical origin or variety, has been a major topic of debate and extensive research. Various instrumental methods (gas chromatography, high pressure liquid chromatography) and sensory analysis, in conjunction with statistical analysis, were developed and applied in an attempt to provide reliable answers to this issue. This research aimed at classifying 33 greek wines from various regions by employing both instrumental and sensory analysis. Application of principal component analysis (PCA) to our experimental data resulted in satisfactory classifications of only Greek red wines in terms of their geographical origin. Greek wines were effectively distinguished in two or three groups (depending on PCA figure); wines from Aegean/Ionean islands. North Greece and South Greece. However, further work with greater numbers of samples is required in order to draw more valid conclusions and to obtain a detailed map of greek wines according to their geographical origin and variety.

The potential of a crude peroxidase (POD) from onion solid waste as a biocatalyst for the synthesis of a naturally occurring aurone is described. The crude enzyme preparation effectively promotes the cyclization of 2′,3,4,4′,6′-pentahydroxy-chalcone (which is not a natural substrate of onion POD) into aureusidin.

The scavenging activities of three standard antioxidants, quercetin, ascorbic acid, and trolox, were evaluated by Co(II)/ethylenediamine-tetraacetic acid (EDTA)-induced luminol chemiluminescence and the 2,2-diphenyl-1-picrylhydrazyl (DPPH*) free radical assay. Therefore, the aim of this study was to characterise an enzyme-free and time-independent chemiluminescence method for the assessment of the scavenging profile of compounds in a cell-free system using the Co(II)/EDTA-luminol-peroxide system. These results showed that the three standards were efficient and effective in inhibiting both Co(II)/EDTA-induced luminol chemiluminescence and the free radical DPPH*. For all the data obtained in this work, the scavenging activity for the standards tested decreased in the following order: quercetin > trolox > ascorbic acid. The present study has applied a simple and precise procedure for the study of hydroxyl radical scavenging activity by Co(II)/EDTA-induced luminol chemiluminescence, and this was assessed by DPPH* free radical scavenging.

1 Arginine-specific ADP-ribosyltransferase (ART) activity has been implicated in white cell chemotaxis. In this study, we examined the capacity of a panel of structurally unrelated inhibitors and pseudo-substrates of ART to inhibit chemotaxis of A7r5 rat vascular smooth muscle cells in response to PDGF-BB. 2 The IC50 values for nicotinamide (12 mM) and novobiocin (165 μM) were similar to those observed for inhibition of chemotaxis by human polymorphonuclear neutrophil leucocytes (PMN), whereas vitamins K3 (IC50=22 μM) and K1 (IC50=95 μM) were less potent than previously described in PMNs. The pseudo-substrates for the enzyme (DEA-BAG, agmatine and arginine-methylester) also inhibited A7r5 chemotaxis, and in addition inhibited cell adhesion at similar concentrations. Vitamin K3 was unique among the inhibitors of ART, in that it also inhibited cell adhesion. 3 A rat ART1 transcript was amplified by rtPCR from rat skeletal muscle, and was noted to share 94% homology with the mouse ART1 cDNA sequence. No such transcript could be detected in A7r5 cells by Northern blot analysis or rtPCR. 4 Evidence for ART activity on the surface of A7r5 cells was investigated using 32P-NAD+ as substrate, and labelled membrane proteins were observed with MWt values of 116, 100, 90 and 70 kDa. Exposure of the labelled proteins to phosphodiesterase yielded 32P-AMP, and hydrolysis with NaOH yielded 32P-NAD+. These results indicated that the labelled proteins were adducts with NAD+, and not the products of ART activity. The absence of ART catalytic activity in A7r5 cells was confirmed in protocols designed to show ADP-ribosylation of agmatine. 5 We conclude that the chemotactic activity of A7r5 cells is independent of ART activity, and the mechanism whereby the novel panel of inhibitors reduced cell migration remains undefined. British Journal of Pharmacology (1998) 125, 152–158; doi:10.1038/sj.bjp.0702027

Hexane extracts obtained by percolation from the leaves of nine Mediterranean plants ( Daphne oleoides , Myrtus communis , Pelargonium zonale , Phillyrea latifolia , Pistacia terebinthus , Quercus pubescens , Rhamnus lucioides , Sideritis syriaca , Smilax aspera ) and from five leaf spices ( Rosmarinum officinalis , Coridothymus capitatus , Laurus nobilis , Salvia fruticosa , Salvia pomifera ) were examined for the presence of tocopherols by thin layer chromatography, gas chromatography, high performance liquid chromatography and combined gas chromatography–mass spectrometry. With the exception of Sideritis syriaca , in all the plants and spices examined α-tocopherol was found to be present. The β - and γ -homologues were detected only in the extracts of Pelargonium zonale and Smilax aspera . Quantitative analysis by HPLC gave values ranging from 250 to 1325 ppm total tocopherols (on a dry leaf basis). These values are higher than those reported for oil seeds (sunflower seed, cottonseed, rapeseed, sesame seed) or other oil sources (peanut, soybean, maize).

Terpenes have numerous applications, ranging from pharmaceuticals to fragrances and biofuels. With increasing interest in producing terpenes sustainably and economically, there has been significant progress in recent years in developing methods for their production in microorganisms. In Saccharomyces cerevisiae, production of the 20-carbon diterpenes has so far proven to be significantly less efficient than production of their 15-carbon sesquiterpene counterparts. In this report, we identify the modular structure of geranylgeranyl diphosphate synthesis in yeast to be a major limitation in diterpene yields, and we engineer the yeast farnesyl diphosphate synthase Erg20p to produce geranylgeranyl diphosphate. Using a combination of protein and genetic engineering, we achieve significant improvements in the production of sclareol and several other isoprenoids, including cis-abienol, abietadiene and β-carotene. We also report the development of yeast strains carrying the engineered Erg20p, which support efficient isoprenoid production and can be used as a dedicated chassis for diterpene production or biosynthetic pathway elucidation. The design developed here can be applied to the production of any GGPP-derived isoprenoid and is compatible with other yeast terpene production platforms.

A method is described for the evaluation of the peroxide value (PV, meq. O 2 kg −1 ) in olive oil. The method is based on the chemiluminogenic energy-transfer reaction of bis(2,4,6-(trichlorophenyl)oxalate (TCPO) with hydrogen peroxide or total peroxides in the presence of Mn(II) as catalyst and 9,10-dimethylanthracene as fluorophore. The procedure developed allows the evaluation of PV within the range of 0.6–100 meq. O 2 kg −1 (CL intensity = 1.76 × PV (meq. O 2 kg −1 ) + 23.2, r 2 = 0.994, n = 9) and relative standard deviation within the range 1–5% by using a simple manual measurement.

The bioactive metabolites derived from weeds have attracted the interest of the food and pharmaceutical industries due to their health benefits.To evaluate the anti-oxidant and acetylcholinesterase activity of Dittrichia viscosa extracts and characterise the polyphenolic metabolites using the LC coupled with diode-array detection (DAD) and positive mode electrospray ionisation (ESI) MS method with a view to evaluating the exploitation potential of this invasive weed.Roots and aerial parts of D. viscosa were extracted with solvents of increasing polarity and their major polyphenolic metabolites were identified by LC - DAD/ESI(+)/MS. The total phenolic content of the extracts was determined using the Folin-Ciocalteu method, while their anti-oxidant activity was evaluated on the basis of their ability to scavenge the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydrogen peroxide. Thin-layer chromatography was used to screen for acetylcholinesterase inhibitors.Stem extracts gave the highest phenolic content, whereas the roots showed the lowest content. Twenty-five polyphenolic constituents of the extracts were tentatively characterised according to their MS and UV spectroscopic data. Among the extracts studied, roots-ethyl acetate and flowers-diethyl ether revealed the highest activity according to the DPPH and chemiluminescence assays respectively.The metabolic profile of D. viscosa was studied and the structures of the major polyphenolic metabolites were tentatively assigned based on their MS and UV-vis spectra. The extracts exhibited high levels of anti-oxidant and acetylcholinesterase inhibitory activity and the inhibitors are probably localised mainly in flowers and roots.

Summary Pickled peppers are preferred by certain consumer groups at reduced pungency. To investigate the reduction in pepper pungency and capsaicin content, fresh ‘Makedoniko’ hot peppers were treated with 0, 0.5 or 1% NaOH before preserved in acid brine for 60 days. Pepper physicochemical traits were monitored following NaOH treatment and during preservation. Capsaicin content was measured in the beginning and at the end of preservation, and the peppers were also tested organoleptically. Preservation in acid brine induced the typical green–yellow product colour, increased firmness and decreased the dry mass in all treatments. NaOH-treated pepper increased phenolics, chlorophyll and antioxidant content in dry mass during preservation faster than the control. Capsaicin content was reduced by 25 or 50% following 0.5 or 1% NaOH treatment, respectively. Pepper organoleptic pungency was also decreased following 1% NaOH treatment. NaOH reduces capsaicin content and pungency of ‘Makedoniko’ pepper, with minor effects on its processed product quality.

Total phenolic content, antioxidant activity and phenolic profiles of six herbal infusions – namely rosemary, Cretan dittany, St. John’s Wort, sage, marjoram and thyme were assayed. Additionally, the infusion anticarcinogenic effect as to their ability to (a) scavenge free radicals, (b) inhibit cell growth, (c) decrease IL-8 levels and (d) regulate p65 subunit in epithelial colon cancer (HT29) and prostate (PC3) cancer cells was investigated. LC-DAD-MS and GC–MS analyses showed major qualitative and quantitative differences in phenolic profiles of the infusions. All herbal infusions exhibited antiradical activity which correlated strongly with their total phenolic content. Infusions exhibited the potential to inhibit cell growth and to reduce IL-8 levels in HT29 colon and PC3 prostate cancer cells. The regulation reported in p65 subunit in HT29 treated with St John’s Wort and in PC3 treated with thyme might point to the NF-κB as the molecular target underlying the effect of these infusions.

1. Mono(ADP-ribosyl)transferase activity has been identified on the external surface of human polymorphonuclear neutrophil leucocytes (PMNs). The enzyme is released from the plasma membrane by phosphoinositide-specific phospholipase C, suggesting a glycosylphosphatidylinositol (GPI) linkage of the enzyme to the plasma membrane. Partial sequence of cDNA encoding the enzyme suggests that it is identical to the GPI-linked mono(ADP-ribosyl)-transferase identified previously on human skeletal muscle. 2. A panel of inhibitors of mono(ADP-ribosyl)transferase (including vitamins K1 and K3, novobiocin and nicotinamide) showed a rank order of inhibitory potency similar to that described for other mono(ADP-ribosyl)transferases. Furthermore, the mono(ADP-ribosyl)ation of agmatine was inhibited also by diethylamino (benzylidineamino)guanidine (DEA-BAG), another substrate of the enzyme related structurally to arginine. 3. There was a close linear correlation between the IC50 values for inhibition of mono(ADP-ribosyl)ation of agmatine by DEA-BAG or the enzyme inhibitors and their IC50 values for inhibition of receptor-dependent polymerization of cytoskeletal actin and chemotaxis. 4. These results suggest a role for mono(ADP-ribosyl)transferase in the transduction pathway involved in receptor-dependent re-alignment of the cytoskeleton during neutrophil chemotaxis.

An Arg-specific mono(ADP-ribosyl)transferase activity on the surface of human polymorphonuclear neutrophil leucocytes (PMNs) was confirmed by the use of diethylamino(benzylidineamino)guanidine (DEA-BAG) as an ADP-ribose acceptor. Two separate HPLC systems were used to separate ADP-ribosyl-DEA-BAG from reaction mixtures, and its presence was confirmed by electrospray mass spectrometry. ADP-ribosyl-DEA-BAG was produced in the presence of PMNs, but not in their absence. Incubation of DEA-BAG with ADP-ribose (0.1-10 mM) did not yield ADP-ribosyl-DEA-BAG, which indicates that ADP-ribosyl-DEA-BAG formed in the presence of PMNs was not simply a product of a reaction between DEA-BAG and free ADP-ribose, due possibly to the hydrolysis of NAD(+) by an NAD(+) glycohydrolase. The assay of mono(ADP-ribosyl)transferase with agmatine as a substrate was modified for intact PMNs, and the activity was found to be approx. 50-fold lower than that in rabbit cardiac membranes. The K-m of the enzyme for NAD(+) was 100.1 +/- 30.4 mu M and the V-max 1.4 +/- 0.2 pmol of ADP-ribosylagmatine/h per 10(6) cells. The enzyme is likely to be linked to the cell surface via a glycosylphosphatidylinositol anchor, since incubation of intact PMNs with phosphoinositol-specific phospholipase C (PI-PLC) led to a 98 %, decrease in mono(ADP-ribosyl)transferase activity in the cells. Cell surface proteins were labelled after exposure of intact PMNs to [P-32]NAD(+). Their molecular masses were 79, 67, 46, 36 and 26 kDa. The time course for labelling was non-linear under these conditions over a period of 4 h. The labelled products were identified as mono(ADP-ribosyl)ated proteins by hydrolysis with snake venom phosphodiesterase to yield 5'-AMP.

In this survey, we analyzed the phenolic profile of six herbal infusions namely Cretan marjoram, pink savory, oregano, mountain tea, pennyroyal and chamomile by LCDAD–MS and by GC–MS. Further, we investigated their anticarcinogenic effect as to their ability to (a) scavenge free radicals (b) inhibit proliferation (c) decrease IL-8 levels and (d) regulate nuclear factor-kappa B in epithelial colon cancer (HT29) and prostate (PC3) cancer cells. All herbal infusions exhibited antiradical activity correlated positevely with total phenolic content. Further, infusions exhibited the potential to inhibit cell proliferation and to reduce IL-8 levels in HT29 colon and PC3 prostate cancer cells. The molecular target for chamomile in HT29 seemed to be the NF-κB, while for the other herbal infusions needs to be identified. This study is the first to show the potential chemopreventive activity of infusions prepared from the examined herbs.

Polyphenolic phytochemicals are of particular importance to the food, pharmaceutical and cosmetics industry, because of their unique antioxidant properties. Red grape pomace is a solid waste of the wine manufacturing process and possesses a very high polyphenolic load, hence its significance as a rich and abundant residua source. However, in many instances there is a lack of analytical data regarding its polyphenolic composition. In this study, red grape pomace originating from the Greek native cultivar Vitis vinifera var. Agiorgitiko was efficiently extracted with 57% aqueous ethanol, which is a non-toxic and environmentally benign solvent, with the aim of obtaining a polyphenol-enriched extract. The extract was subsequently analyzed by liquid chromatography-diode array-mass spectrometry analysis, in order to tentatively characterize the major phytochemicals recovered. The compounds identified were a p-coumaric acid derivative, three flavonol conjugates (two glucosides and a glucuronide), along with three anthocyanin pigments that occur in grape berries. Three other major phenolics detected could not be assigned to a tentative formula and their structural elucidation merits further investigation. The data generated from this study could be used in assessing the overall polyphenolic profile of the pomace from this particular Greek, native variety, which could be of value in producing commercial formulations with high antioxidant activity.

The oxidation products of a previously tested prooxidant mixture of quercetin (Q) and caffeic acid (CA) at 1:2 ratio were analysed by LC–MS. The UV–Vis and MS spectra of three chromatographic peaks eluting at t R = 9.11 min, t R = 14.36 min and t R = 30.30 min were studied further. The structures of the tentatively identified compounds indicate polymeric molecules. A pentamer formed by 3 units of quercetin and 2 units of caffeic acid was attributed in the case of peaks t R = 9.11 min and t R = 14.36 min. The quercetin quinone (QQ) – a polymerization intermediate – is a fragment of the compound identified in the MS spectrum with the m / z = 323 coming from Q o -quinone m / z = 300 plus 23 from Na + . According to the UV–Vis spectrum, we suggest a different intermolecular arrangement which gives a more extended e-delocalisation. At t R = 30.30 min, the spectra helped us to tentatively identify this oxidation product as being a polymer of 4 CA units and 1 QQ.

National audience; The 2012 edition of Mediterra takes the mobilising potential of the Mediterranean Diet as a basis and proposes a multidimensional itinerary involving sociodemographics, health, ecology, enterprise, geo-economics and citizens’ initiative. Consumers in the countries of the Mediterranean Basin have progressively changed their dietary practices as they have gradually become caught up in the dynamics of urbanisation and the globalisation of agricultural trade. They are adhering less and less to the Mediterranean Diet, despite the fact that it is the basis of their identity and one of the major assets of the region. Pressures on natural resources and the emergence of new private actors are compounding the complexity of diet-related issues. Already the subject of widespread sociocultural and scientific debate and research, the Mediterranean Diet merits reconsideration from the political point of view given the growing awareness of the strategic dimension of agriculture and the crucial role played by food production in the stability and development of societies. This diet, whose health-promoting virtues are widely recognised and which UNESCO has now listed as part of the intangible cultural heritage of humanity, is now raising questions in the fields of environmental responsibility and political action to promote greater regional cooperation.; L’édition 2012 de Mediterra fonde sa réflexion sur le potentiel mobilisateur de la diète méditerranéenne en proposant un itinéraire multidimensionnel qui fait appel à l’histoire, à la sociodémographie, à la santé, à l’écologie, à l’entreprise, à la géoéconomie et à l’initiative citoyenne. Aspirés par les dynamiques de l’urbanisation et de la mondialisation des échanges agricoles, les consommateurs du pourtour méditerranéen ont progressivement modifié leurs pratiques alimentaires. Socle identitaire et richesse de cet espace, la diète méditerranéenne y est pourtant de moins en moins observée. Les tensions sur les ressources naturelles et l’émergence de nouveaux acteurs privés catalysent la complexité des enjeux liés aux régimes alimentaires. Alors qu’elle fait l’objet de nombreux débats et recherches sur le plan socioculturel et scientifique, la diète méditerranéenne mérite d’être reconsidérée sur le terrain politique à l’heure où l’on constate de nouveau la dimension stratégique de l’agriculture et le rôle central de l’alimentation pour la stabilité et le développement des sociétés. Reconnue pour ses vertus sanitaires, inscrite au patrimoine culturel immatériel de l’humanité, la diète méditerranéenne interroge désormais les champs de la responsabilité environnementale et de l’action politique en faveur d’une plus grande coopération régionale.

Phytochemical analyses of weeds, many of which have been used in traditional medicine worldwide, could lead to the identification of secondary metabolites with significant biological activity.To perform an assessment of the chemical composition and exploitation potential of the invasive weed Oxalis pes-caprae. To evaluate the anti-oxidant activity of its extracts and isolate and characterise polyphenolic metabolites using LC-DAD-MS (ESI+) and NMR methods.Aerial parts of the invasive weed O. pes-caprae were extracted with solvents of increasing polarity and their major polyphenolic metabolites were identified by LC-DAD-MS (ESI+). The total phenolic content of the extracts was determined using the Folin-Ciocalteu method, while their anti-oxidant activity was evaluated on the basis of their ability to scavenge the stable free radical 1,1-diphenyl-2-picrylhydrazyl and hydrogen peroxide.The major polyphenolic constituents of the extracts were tentatively characterised as chlorogenic acid, quinic ferulate, luteolin glucoside and cernuoside according to their MS and UV spectroscopic data. Cernuoside, an aureusidin glucoside, was isolated from the methanolic extract of the weed's flowers and its structure was unambiguously identified by 1D- and 2D-NMR spectroscopy. The butanol extract of O. pes-caprae displayed the highest anti-oxidant activity.The metabolic profile of O. pes-caprae was studied and the structures of the major polyphenolic metabolites based on their MS and UV-vis spectra were tentatively assigned. The aureusidin glucoside cernuoside was isolated and characterised for the first time from O. pes-caprae. The extracts exhibited high levels of anti-oxidant activity.

High-performance liquid chromatography with confirmation by UV-visible photodiode array detector-positive electrospray ionization-mass spectrometry [HPLC-UV-vis-DAD-(+ESI)-MS] with enhanced fragmentation by appropriate adjustment of the cone voltage was used to determine bioflavonoid content of five citrus species (tangerine, sanguine, sour orange, lemon and grapefruit) cultivated in Greece which come from citrus varieties analyzed for the first time. The main groups of bioflavonoids found in the juice of the citrus species according to HPLC retention times, spectral data and literature references were O-glycosylated flavanones and flavones, C-glucosylated flavones, O-glucosylated flavones, O-C-glucosylated flavones like saponarin and a phenolic derivative.

Hetero Diels-Alder reaction of diene 7, obtained in four steps from aldehyde 4, with Troc-NO 8 produced the dihydro-2H-1,2-oxazine 9 in 48% yield. Conversion of this intermediate to the N-deprotected tosylate 10 followed by ring closure gave the bicyclic product 11 which was converted to the indolizidine derivative 13 by N‒O bond cleavage (H2, RaNi) and recyclization under Mitsunobu conditions. Final deprotection of 13 with mild acid gave the target triepicastanospermine analog 3.

Hetero Diels-Alder reaction of diene 10 , obtained in one step from aldehyde 4 , with nitroso dienophile 6 produced the dihydro-2H-1,2-oxazines 12 . Treatment of the tosylates 13 derived from 12 with TBAF induced a ring contraction process leading directly to pyrrole 16 . Cyclization of this intermediate furnished the pyrrolo-castanospermine derivative 17 .

Hetero Diels-Alder reaction of diene 10 , obtained in one step from aldehyde 4 , with nitroso dienophile 6 produced the dihydro-2H-1,2-oxazines 12 . Treatment of the tosylates 13 derived from 12 with TBAF induced a ring contraction process leading directly to pyrrole 16 . Cyclization of this intermediate furnished the pyrrolo-castanospermine derivative 17 .

A series of 2'-hydroxy-chalcones and their oxidative cyclization products, aurones, have been synthesized and tested for their antioxidant and lipoxygenase inhibitory activity. The natural product aureusidin (31) was synthesized in high yield by a new approach. An extensive structure-relationship study was performed and revealed that several chalcones and aurones possess an appealing pharmacological profile combining high antioxidant and lipid peroxidation activity with potent soybean LOX inhibition.

The development of browning as a function of basic compositional parameters, including phenolics, Fe3+ and SO2, was studied on the basis of white wine-like model matrices. The influence of these three factors was approached through the implementation of a 23 full factorial design and response surface methodology. The model implemented produced a satisfactory fitting of the data (R2 = 0.94, P = 0.0136). The second order equation that was extracted out of the model indicated that the concentration of the phenolic substrate is the major determinant in the onset of A420 (browning), whereas the role of either Fe3+ or SO2 was less pronounced. The outcome of the study was discussed with regard to the applicability of the model established on more complex mixtures and real matrices (white wines). PRACTICAL APPLICATIONS Browning development during storage of white wines is a serious defect, with important consequences to the quality and eventually the marketability of these commodities. To date, the examinations pertaining to the clarification of factors that can affect browning were based on rather unilateral assessment, while it is generally accepted that browning depends on several compositional parameters, which render the phenomenon a particular complexity. In this view, the implementation of factorial design with respect to investigating in parallel several factors pertaining to browning development becomes imminent. Thus, the establishment of models on such a sound experimental basis is expected to provide a reliable background for more accurate and thorough evaluation, with a potential direct industrial applicability.

An experimental setup based on a 2(3) full-factorial, central-composite design was implemented with the aim of optimising the recovery of polyphenols from olive leaves by employing reusable and nontoxic solutions composed of water/ethanol/citric acid as extracting media. The factors considered were (i) the pH of the medium, (ii) the extraction time and (iii) the ethanol concentration. The model obtained produced a satisfactory fit to the data with regard to total polyphenol extraction (R(2) = 0.91, p = 0.0139), but not for the antiradical activity of the extracts (R(2) = 0.67, p = 0.3734). The second-order polynomial equation obtained after analysing the experimental data indicated that ethanol concentration and time mostly affected the extraction yield, but that increased pH values were unfavourable in this regard. The maximum theoretical yield was calculated to be 250.2 +/- 76.8 mg gallic acid equivalent per g of dry, chlorophyll-free tissue under optimal conditions (60% EtOH, pH 2 and 5 h). Liquid chromatography-electrospray ionisation mass spectrometry of the optimally obtained extract revealed that the principal phytochemicals recovered were luteolin 7-O-glucoside, apigenin 7-O-rutinoside and oleuropein, accompanied by smaller amounts of luteolin 3',7-O-diglucoside, quercetin 3-O-rutinoside (rutin), luteolin 7-O-rutinoside and luteolin 3'-O-glucoside. Simple linear regression analysis between the total polyphenol and antiradical activity values gave a low and statistically insignificant correlation (R(2) = 0.273, p > 0.05), suggesting that it is not the sheer amount of polyphenols that provides high antioxidant potency; instead, this potency is probably achieved through interactions among the various phenolic constituents.

The exploitation of food residuals can be a major contribution in reducing the polluting load of food industry waste and in developing novel added-value products. Plant food residues including trimmings and peels might contain a range of enzymes capable of transforming bioorganic molecules, and thus they may have potential uses in several biocatalytic processes, including green organic synthesis, modification of food physicochemical properties, bioremediation, etc. Although the use of bacterial and fungal enzymes has gained attention in studies pertaining to biocatalytic applications, plant enzymes have been given less consideration or even disregarded. Therefore, we investigated the use of a crude peroxidase preparation from solid onion by-products for oxidizing ferulic acid, a widespread phenolic acid, various derivatives of which may occur in food wastes. The highest enzyme activity was observed at a pH value of 4, but considerable activity was retained up to a pH value of 6. Favorable temperatures for increased activity varied between 20-40 degrees C, 30 degrees C being the optimal. Liquid chromatography-mass spectrometry analysis of a homogenate/H(2)O(2)-treated ferulic acid solution showed the formation of a dimer as a major oxidation product.