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PubMed2004

Analysis of aged red wine pigments by capillary zone electrophoresis.

Red wines of different ages (1-14 years) were analysed by Capillary zone electrophoresis (CZE). Pigments were separated using a fused silica capillary with an effective length of 56 cm and an internal diameter of 75 cm. Disodium tetraborate at 50 mM with a pH of 9.4 was used as buffer solution with methanol as modifier. Electrophoregrams were recorded at 280, 520 and 599 nm and spectra were measured from 200 to 599 nm using a diode array detector. Several differences in the CZE signals obtained for different aged wines were observed, as well as between red and white wines. The signals of a group of seven peaks increased in mature wines. A decrease in free anthocyanins was also identified in aged wine. The migration times of these compounds corresponded to charge/size ratios higher than those of free anthocyanins, and their spectra suggested combinations of anthocyanins with flavanols or tannins. The global CZE response of these pigmented polyphenolic polymers was linearly correlated with the spectrophotometric determination of polymeric pigments (96%) and age (92%).

Electrophoresis, Capillary↗
PubMed2005

Molecular characterisation of birch bark tar by headspace solid-phase microextraction gas chromatography-mass spectrometry: a new way for identifying archaeological glues.

To develop an analytical methodology, as non-destructive as possible, suitable for the identification of natural substances from archaeological origin, we studied the potentiality of solid-phase microextraction (SPME) for analysing birch bark tar, an adhesive commonly used during ancient times. First of all, birch bark tars were produced by a controlled heating of birch bark. The two kinds of samples obtained using different processes of fabrication, one at liquid state, the second one at solid state, were then analysed by headspace HS-SPME-GC-MS. Different conditions of sample treatment were tested (two different fibre coatings, various times and temperatures of extraction) in order to suggest optimal conditions for the analysis of birch bark tar. Both samples were shown to be rich in volatile organic components. Two main groups of constituents, namely phenolic compounds issued from lignin or tannin known to be present in bark and sesquiterpenoid hydrocarbons, secondary metabolites largely distributed in the plant kingdom, were detected for the first time in birch bark tar. HS-SPME-GC-MS appears thus to be a very efficient method for investigating the volatiles emitted by plant tars and could be further used for the study of birch bark tar samples issued from archaeological context.

Adhesives↗
PubMed2004

Pomegranate juice consumption for 3 years by patients with carotid artery stenosis reduces common carotid intima-media thickness, blood pressure and LDL oxidation.

Dietary supplementation with polyphenolic antioxidants to animals was shown to be associated with inhibition of LDL oxidation and macrophage foam cell formation, and attenuation of atherosclerosis development. We investigated the effects of pomegranate juice (PJ, which contains potent tannins and anthocyanins) consumption by atherosclerotic patients with carotid artery stenosis (CAS) on the progression of carotid lesions and changes in oxidative stress and blood pressure. Ten patients were supplemented with PJ for 1 year and five of them continued for up to 3 years. Blood samples were collected before treatment and during PJ consumption. In the control group that did not consume PJ, common carotid intima-media thickness (IMT) increased by 9% during 1 year, whereas, PJ consumption resulted in a significant IMT reduction, by up to 30%, after 1 year. The patients' serum paraoxonase 1 (PON 1) activity was increased by 83%, whereas serum LDL basal oxidative state and LDL susceptibility to copper ion-induced oxidation were both significantly reduced, by 90% and 59%, respectively, after 12 months of PJ consumption, compared to values obtained before PJ consumption. Furthermore, serum levels of antibodies against oxidized LDL were decreased by 19%, and in parallel serum total antioxidant status (TAS) was increased by 130% after 1 year of PJ consumption. Systolic blood pressure was reduced after 1 year of PJ consumption by 12% [corrected] and was not further reduced along 3 years of PJ consumption. For all studied parameters, the maximal effects were observed after 1 year of PJ consumption. Further consumption of PJ, for up to 3 years, had no additional beneficial effects on IMT and serum PON1 activity, whereas serum lipid peroxidation was further reduced by up to 16% after 3 years of PJ consumption. The results of the present study thus suggest that PJ consumption by patients with CAS decreases carotid IMT and systolic blood pressure and these effects could be related to the potent antioxidant characteristics of PJ polyphenols.

Aged↗
PubMed2005

A potent sperm motility-inhibiting activity of bioflavonoids from an ethnomedicine of Onge, Alstonia macrophylla Wall ex A. DC, leaf extract.

The methanol extract (ME) and the n-butanol fractions of methanolic extract of Alstonia macrophylla Wall ex A. DC leaves were investigated on the forward motility (FM) of mammalian (goat and human) spermatozoa. The ME at 600 microg mL-1 as well as fraction B at 100 microg mL-1 concentrations showed marked inhibition of sperm FM in both goat and human species when tested by microscopic and spectrophotometric methods. Approximately 60-80% of the goat spermatozoa lost their FM when treated with 600 microg mL-1 of ME and 100 microg mL-1 of fraction B. At 100 microg mL-1 concentration, fraction B showed 90% loss of FM in human spermatozoa, while fraction B at 400 microg mL-1 concentration showed complete inhibition of sperm FM at 0 min. The inhibitory activity of fraction B increases with increasing concentration in a dose-dependent manner. Phytochemical study of the extract revealed that the leaf contains tannins, flavonoids, sterols, triterpenes, alkaloids and reducing sugars. Further fractionation and purification of the bioactive n-butanol part of ME showed the presence of ursolic acid (fraction B), beta-sitosterol (fraction A), beta-sitosterol glucoside and a mixture of minor compounds (fraction C, detected on thin-layer chromatography). The results reveal that fraction B (ursolic acid), a pentacyclic triterpene, has the potential of sperm motility inhibition and can serve as a topical vaginal contraceptive.

Alstonia↗
PubMed2006

Ecotoxicological evaluation of cork-boiling wastewaters.

Toxicity tests with Vibrio fischeri, Daphnia magna, and Lemna minor were used to evaluate acute and chronic toxicity of cork-boiling wastewaters and correlation analysis was performed with physicochemical parameters. Acute toxicity values (EC(50)) ranged from 2.3% to 24.2% in the Microtox test and from 4.4% to 29.5% in the Daphnia test. According to these values, 78% of the samples were classified as acutely toxic to the most sensitive species (V. fischeri). Significant correlation was obtained between EC(50) and chemical oxygen demand, biochemical oxygen demand after 5 days, total organic carbon, tannin and lignin and total solids. No significant correlation was found between the two acute tests. The D. magna chronic test showed significant differences between all tested concentrations and the control, with an EC(50) of 0.32%. An EC(50) value of 26.0% was calculated for L. minor. For the analysis of cork-boiling wastewater toxicity and routine biomonitoring, the use of the Microtox test is suggested, to afford greater environmental protection.

Aliivibrio fischeri↗
PubMed2006

Degradation of xenobiotics originating from the textile preparation, dyeing, and finishing industry using ozonation and advanced oxidation.

Effluents from textile preparation, dyeing, and finishing processes contain high concentrations of biologically difficult-to-degrade or even inert auxiliaries. Under these circumstances, it most often becomes inevitable to apply energy-intense and hence "imperative" treatment technologies (so-called advanced oxidation processes, AOPs) to achieve an acceptable reduction in the organic content of the effluent, thereby improving the biocompatibility of the originally refractory wastewater. The present experimental study focused on three problematic dyehouse effluent streams in order to alleviate the problem of toxicity and recalcitrance arising from the use of certain textile chemicals at source. For that purpose, the textile preparation stage was simulated by a nonionic surfactant (NS), the polyamide dyeing stage by a synthetic tannin (syntan; ST), and an aqueous biocidal finishing (BF) solution was employed to mimic typical textile finishing effluent. Synthetic effluent streams bearing NS, ST, or BF were subjected to treatment with different, well-established AOPs (ozonation at varying pH; advanced oxidation with H(2)O(2)/UV-C at varying H(2)O(2) concentrations) in order to degrade the active ingredients of the auxiliary formulations, thereby eliminating their toxicity and recalcitrance. Baseline experiments were conducted in order to optimize AOP conditions that were consecutively applied to observe changes in the originally poor effluent biodegradability and high toxicity. Obtained experimental findings revealed that (i) the COD content of NS could be reduced by at least 50% after H(2)O(2)/UV-C treatment at pH 9.0 accompanied by a nearly twofold improvement in its already fair biodegradability; (ii) the inhibitory effect of the biochemically reluctant ST on heterotrophic biomass was completely eliminated upon ozonation (dose=900 mg h(-1)) at pH 3.5; and (iii) the microbial toxicity exerted by BF totally disappeared after ozonation (dose=600 mg h(-1)) at pH 7.2. However, the achievement of detoxification and/or biodegradability improvement was accompanied with high electrical energy requirements.

Biodegradation, Environmental↗
PubMed2004

Effects of ozone on the foliar histology of the mastic plant (Pistacia lentiscus L.).

An open-top chamber study was conducted to investigate the tissue and cellular-level foliar effects of ozone (O3) on a Mediterranean evergreen species, the mastic plant (Pistacia lentiscus L.). Plants were exposed at three different O3 levels, and leaf samples were collected periodically from the beginning of the exposure. Although no visible foliar injury was evident, alterations of the plastids and vacuoles in the mesophyll were observed. Senescence processes were accelerated with an anomalous stacking of tannin vacuoles, and a reduction in the size and number of the chloroplasts. Overall, most of the modifications induced by O3 were consistent with previously reported observations on deciduous broadleaf species, with the exception of alterations in the cells covering the secretory channels, reported here as a new finding. Comments on the feasibility of using microscopy to validate O3 related field observations and subtle foliar injury are also given.

Air Pollutants↗
PubMed2005

Changes in the concentrations of phenolics and photosynthates in Scots pine (Pinus sylvestris L.) seedlings exposed to nickel and copper.

Studies were done on the effects of elevated soil concentrations of copper (Cu) and (Ni) on foliar carbohydrates and phenolics in Scots pine (Pinus sylvestris L.). Four year-old seedlings were planted in pots filled with metal-treated mineral forest soil in early June. The experimental design included all combinations of four levels of Cu (0, 25, 40 and 50 mg kg(-1) soil dw) and Ni (0, 5, 15 and 25 mg kg(-1) soil dw). Current year needles were sampled for soluble sugar, starch and phenolics at the end of September. Ni increased sucrose concentration in the needles, indicating disturbances in carbohydrate metabolism. Trees exposed to Ni had higher concentrations of condensed tannins compared with controls. In contrast, concentrations of several other phenolic compounds decreased when seedlings were exposed to high levels of Cu or to a combination of Ni and Cu. The results suggest that concentrations of phenolics in Scots pine needles vary in their responses to Ni and Cu in the forest soil.

Carbohydrates↗
PubMed2005

Dietary unripe apple polyphenol inhibits the development of food allergies in murine models.

The incidence of type I allergic disorders has been increasing worldwide, particularly, the hypersensitivity to food. We first showed that apple condensed tannin (ACT) intake would inhibit the development of the oral sensitization and that the inhibition could correlate with the rise in the population of TCR(gamma)delta-T cells in the intestinal intraepithelial lymphocytes (IEL) using W/W(V) mice and B10A mice which were ovalbumin (OVA)-orally sensitized. Serum OVA-specific immunoglobulin E and immunoglobulin G1 titers in the OVA-orally sensitized W/W(V) and B10A mice ad libitium fed ACT were extremely inhibited compared to those of the control. The ACT intakes of OVA-sensitized W/W(V) and B10A mice inhibited the immediate reduction of the body temperature or the rise in serum histamine induced by active systemic anaphylaxis. The proportions of the TCR(gamma)delta-T cells in the IEL of the OVA-orally sensitized W/W(V) and B10A mice ad libitium fed ACT were significantly greater than that in the controls. Furthermore, ACT feeding by itself could induce the rise in the percentage of the TCR(gamma)delta-T cells among the IEL of the W/W(V) and B10A mice. This suggests that the ACT intake may prevent the development of food allergies and this effect could be correlated with the rise in the percentage of TCR(gamma)delta-T cells among the IEL.

Allergens↗
PubMed2004

Free radical scavenging activity of extracts prepared from fresh leaves of selected Chinese medicinal plants.

The free radical scavenging activity of the 80% methanolic extracts from fresh leaves of 300 Chinese medical woody plants was assessed with the aid of the stable DPPH radical. Among the plants screened, 56 species had strong free radical scavenging capacities, with IC50 values lower than 0.5 mg leaves per milliliter. Analysis of the medical uses of these plants showed that most of them are employed for their effects on hemostasis, as anti-inflammatory, antimicrobial or for treatment of dysentery. These uses may be directly linked to the content in tannins and flavonoids and consequently to their free radical scavenging activities.

Biphenyl Compounds↗
PubMed2004

CNS activity of Alstonia macrophylla leaf extracts: an ethnomedicine of Onge of Bay Islands.

Methanol extract at 100-200 mg/kg p.o. and major nonpolar fraction B at 50 mg/kg of Alstonia macrophylla leaves caused a significant reduction in spontaneous activity, remarkable decrease in exploratory behavioural pattern, a reduction in muscle relaxant activity and also significantly potentiated phenobarbitone sodium-induced sleeping time. The phytochemical study of crude leaf extract revealed the presence of tannin, triterpenoid, flavonoid, sterol, alkaloid and reducing sugars. Further fractionation and purification of the n-butanol part of methanol extract yielded fraction A, fraction B and fraction C along with some minor fatty acids as the major compounds.

Alstonia↗
PubMed2004

A new diglycosyl megastigmane from Carallia brachiata.

A new megastigmane diglycoside was isolated from the leaves of Carallia brachiata. The structure was determined by spectroscopic methods as 3-hydroxy-5,6-epoxy-beta-ionol -3-O-beta-apiofuranosyl-(1-->6)-beta-glucopyranoside (1). Additionally, 29 known compounds consisting of two megastigmanes, one 1,2-dithiolane derivative, seven aromatic compounds, five condensed tannins, 12 flavonoids, and two glyceroglycolipids were isolated and identified.

Cyclohexanones↗
PubMed2005

Sedative and anticonvulsant effects of hydroalcoholic extract of Equisetum arvense.

The hydroalcoholic extract of Equisetum arvense (HAE) tested at the doses of 200 and 400 mg/kg showed a significant activity on the open-field, enhanced the number of falls in the rota-rod reducing the time of permanence in the bar and increased the sleeping time (46% and 74%) in the barbiturate-induced sleeping time. In the pentylenetetrazole-seizure, it increased the first convulsion latency, diminished the severity of convulsions, reduced the percentage of animals which developed convulsion (50% and 25%) and protected animals from death. On the contrary, in the elevated plus maze, the doses 50, 100 and 150 mg/kg did not affect the evaluated parameters. Thus, HAE presented anticonvulsant and sedative effects. Phytochemical analysis detected the presence of tannins, saponins, sterols and flavonoids.

Animals↗
PubMed2005

Partial 26S rDNA restriction analysis as a tool to characterise non-Saccharomyces yeasts present during red wine fermentations.

Restriction patterns of amplified regions of ribosomal large subunit RNA encoding genes (26S rDNA) were evaluated as a routine methodology to examine yeast species diversity during red wine fermentation. The results were confirmed by sequencing of D1/D2 region of 26S rDNA. Red wine production was carried out using a yeast starter culture together with different commercial products, namely enzymes, fermentation activators and tannins and their influence on the non-Saccharomyces yeast population was studied. Yeast strains were isolated using lysine agar as a selective medium for non-Saccharomyces yeasts, after morphological characterisation of colonies. Amplification of 26S rDNA followed by digestion with three restriction enzymes applied to the 121 isolates, generated 19 profiles and a very high correlation with sequencing results was achieved. Although a starter yeast culture was added, results showed that several yeast species were present during all stages of fermentation, independent of the conditions tested, emphasizing the diversity of microorganisms associated with winemaking. On the other hand commercial additives did not significantly influence the diversity of yeast population during the fermentation process. For non-Saccharomyces strains, restriction patterns of a PCR amplified 26S rDNA region proved to be an adequate tool for clustering strains at species level and enabled the monitoring of yeast population dynamics during red wine fermentation.

Base Sequence↗
PubMed2005

Both arginine and fructose stimulate pH-independent resistance in the wine bacteria Oenococcus oeni.

The wine bacteria Oenococcus oeni has to cope with harsh environmental conditions including an acidic pH, a high alcoholic content, and growth inhibitory compounds such as fatty acids, phenolic acids and tannins. So how can O. oeni bacteria naturally present on the surface of grape berries acquire a natural resistance that will alleviate the effect of wine stresses? One mechanism displayed by O. oeni and many other bacteria against the damaging effects of acid environments is arginine consumption through the arginine deiminase pathway. Various studies have shown that the bacterial protection conferred by arginine depends on the rise in pH associated with ammonia production. However, many experimental results disagree with this point of view. The aim of this study was to clarify the protective effect of arginine on O. oeni stress adaptation. Is it only by increasing the pH through ammonia production that this effect is triggered, or does stimulation of appropriate cellular responses play an additional role? This study shows that: (a) arginine in combination with fructose triggers the expression of a subset of genes which are also stress-responsive; (b) cultivation of O. oeni in a fructose- and arginine-supplemented medium prior to wine exposure protects bacteria against subsequent wine shock, and (c) this acquired stress resistance is independent of pH.

Adaptation, Physiological↗
PubMed2004

Anti-nociceptive and anti-inflammatory activities of the methanolic extract of Parinari polyandra stem bark in rats and mice.

The methanolic extract of the stem bark of Parinari polyandra (family Rosaceae) was investigated for possible anti-nociceptive and anti-inflammatory effects in mice and rats. Three models were used to study the extracts effects on nociception which were the acetic acid-induced abdominal constriction test, hot-plate method (both in mice) and the formalin test in rats. The anti-inflammatory effects were investigated employing the albumin-induced hind-paw oedema in rats. Results of the study revealed the extract to have significant (P<0.05) anti-nociceptive effect at a dose of 200 mg/kg p.o. in mice and rats in all the models for anti-nociception while 100 mg/kg p.o. showed significant (P<0.05) effect in the acetic acid-induced abdominal constriction test and in phase I of the formalin test. The extract also exhibited anti-inflammatory effects which were found to be significant (P<0.05) at 200 mg/kg p.o. in the rats tested. Preliminary phytochemical screening of the extract showed the presence of flavonoids, tannins, and saponin glycoside. The results suggest the extract contains pharmacologically active principles. The result is in agreement with the local application of the plant in painful and inflammatory conditions.

Analgesics↗
PubMed2004

In vitro antitrypanosomal activity of ethnopharmacologically selected Beninese plants.

The in vitro antitrypanosomal activity of methylene chloride, methanol and aqueous extracts of the leaves and twigs of five plant species traditionally used in Benin for the treatment of sleeping sickness were evaluated on Trypanosoma brucei brucei and their selectivity was analysed on Leishmania mexicana mexicana and J774 macrophage-like murine cells. The results showed that the four most active extracts had MIC values < or =19 microg/ml (Hymenocardia acida twig and leaf, Strychnos spinosa leaf, Trichilia emetica leaf methylene chloride extracts). All these extracts had a lower activity on L. m. mexicana and J774 cells. Determination of the IC50 values of the methylene chloride leaf extracts on two strains of trypanosomes (T. b. brucei and T. b. rhodesiense) and two mammalian cell lines (L6 and J774 cells) showed that all extracts possessed some antitrypanosomal activity with IC50's ranging from 1.5 to 39 microg/ml. All were also toxic to the mammalian cells, but usually with higher IC50's. The only exception was the S. spinosa methylene chloride leaf extract which had no toxicity on J774 cells. Although tannins have been identified in most of the species studied, they could not be detected in the most active extracts, just as alkaloids. The presence of flavonoids and quinones may at least in part explain the observed activities of some of the active extracts.

Animals↗
PubMed2004

In vitro effects of aqueous seeds extract of Acacia cyanophylla on the opsonized zymosan-induced superoxide anions production by rat polymorphonuclear leukocytes.

In vitro studies were carried out in rat pleural polymorphonuclear leukocytes (PMNs) activated by opsonized zymosan (OZ) to investigate the effects of aqueous extract from Acacia cyanophylla seeds on superoxide anions generation. PMNs were collected, after induction of an acute inflammatory reaction, by injection in the rat pleural cavity, of a suspension of calcium pyrophosphate (CaPP) crystals (pleurisy with CaPP) or serum (pleurisy with serum). The results obtained indicate that Acacia cyanophylla aqueous seeds extract had, in vitro, a significant stimulatory effect, in a dose dependent manner, on the PMN superoxide anions generation. It also corrected the diminution of superoxide anions production induced by diclofenac pre-treated PMNs. It could be concluded from the results of this study that the stimulatory properties of Acacia cyanophylla seeds aqueous extract may at least be due to the presence of polyphenols such tannins and/or lignins. Further investigations are needed to determine clearly the mechanisms mediating the generation of superoxide radicals in this phenomenon.

Acacia↗

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