Toxicity and antioxidant activity in vitro and in vivo of two Fucus vesiculosus extracts.

The consumption of seaweeds has increased in recent years. However, their adverse and beneficial effects have scarcely been studied. Two extracts from the brown seaweed Fucus vesiculosus containing 28.8% polyphenols or 18% polyphenols plus 0.0012% fucoxanthin have been obtained and studied to determine their toxicity in mice and rats and also their antioxidant activity. Both extracts were shown to lack any relevant toxic effects in an acute toxicity test following a 4 week daily treatment in rats. The extracts exhibited antioxidant activity in noncellular systems and in activated RAW 264.7 macrophages, as well as in ex vivo assays in plasma and erythrocytes, after the 4 week treatment in rats. Our ex vivo results indicated that compounds from extract 2 may be more easily absorbed and that the antioxidants in their parent or metabolized form are more active. These findings support the view that the daily consumption of F. vesiculosus extract 2 (Healsea) would have potential benefits to humans.

Dealcoholized red and white wines decrease oxidative stress associated with inflammation in rats.

In vitro experiments have demonstrated that polyphenols exhibit antioxidant and anti-inflammatory activities. The present study was designed to test whether dealcoholized red (DRW) and white (DWW) wines can decrease the oxidative stress associated with inflammation in vivo. Rats were fed for 15 d either a control diet or one supplemented with DRW or DWW. Finally, a granuloma was induced by subcutaneous administration of carrageenan. Although DRW showed higher antioxidant activity in vitro than DWW, both wines decreased the number of cells recruited into the granuloma pouch. Malondialdehyde decreased in plasma and inflammatory exudate from rats fed with DRW- and DWW-rich diets. Moreover, the concentration of NO increased in exudate, which correlates with the increase in the citrulline:arginine ratio. Polymorphonuclear leucocytes from the inflammatory exudate of rats fed dealcoholized wines showed decreased superoxide anion (O*2) production and increased NO production ex vivo. This change in NO production resulted from increased expression and activity of inducible NO synthase (EC 1.14.13.39). Moreover, the up regulation of cyclo-oxygenase-2 (EC 1.14.99.1) protein expression observed in rats fed the DRW-rich diet was not related to a direct effect of NO. The present results indicate that the non-alcoholic compounds of wines not only improve antioxidant status in an inflammatory situation, but also limit cell infiltration, possibly through a decrease in O*2 and an increase in NO production.

Polyphenol pattern and antioxidant activity of different tomato lines and cultivars.

BACKGROUND/AIMS: Besides antioxidant vitamins and minerals, fruits and vegetables contain flavonoids and related phenolics. The biological activities of these polyphenols have become well known in recent years evidencing their beneficial effects on human health. In this context, the characterization of the flavonoids present in tomatoes is of great interest. Thus the polyphenol pattern (including flavonols, flavanones and cinnamate derivatives), lycopene and beta-carotene concentrations and the total antioxidant activity (TAA) of the phenolic fraction from different tomato lines and cultivars have been determined. METHODS: The characterization was obtained by means of spectrophotometry and HPLC analyses. RESULTS: Mean values for single flavonoids were 0.68 +/- 0.16 for naringenin, 0.74 +/- 0.12 for rutin and 0.32 +/- 0.06 for a rutin-pentoside. Mean total polyphenol content was 13.15 +/- 1.15 mg/100 g and mean TAA value was 1.3 +/- 0.10 mmol/g. The obtained TAA values resulted in good accordance with the total polyphenol content (R(2) = 0.7928). The main phenolic acids were chlorogenic (mean +/- SE 0.20 +/- 0.03) and caffeic acid (mean +/- SE 0.03 +/- 0.01). Mean levels of lycopene and beta-carotene were 5.38 +/- 0.90 and 1.18 +/- 0.40 mg/100 g, respectively. CONCLUSIONS: Almost all the lines characterised by low carotenoid content produce high levels of polyphenols, and consequently have the most powerful antioxidant potential.

Plasma levels of caffeic acid and antioxidant status after red wine intake.

The aim of this study was to evaluate the bioavailability of caffeic acid and the modification of plasma antioxidant status following red wine intake. Five healthy male volunteers consumed 100, 200, and 300 mL of red wine corresponding to approximately 0.9, 1.8, and 2.7 mg of caffeic acid, respectively. Plasma samples collected at different times (0-300 min) were evaluated for their content of caffeic acid and their total antioxidant status. Both these parameters, i.e., plasma concentration of caffeic acid and antioxidant potential, were dose-dependent and the C(max) was reached at about 60 min after red wine intake. The results indicate that caffeic acid is bioavailable and it may be correlated with the antioxidant potential of plasma.

Polyphenol content and total antioxidant activity of vini novelli (young red wines).

Eight commercial Italian vini novelli (red wines prepared by carbonic maceration and supposed to be consumed within three months from their wine-making) were evaluated for their total antioxidant activity. The wines had an average total phenol content (1605.4 +/- 337.4 mg/L gallic acid equivalents) lower than that of wines prepared by traditional maceration and consumable after aging (2057. 3 +/- 524.0 mg/L gallic acid equivalents). The average flavanol content (424.7 +/- 121.3 mg/L catechin equivalents) and the total antioxidant activity (16.8 +/- 3.8 mmol/L Trolox equivalents) of vini novelli were higher than the corresponding values (382.7 +/- 174.5 mg/L catechin equivalents and 12.3 +/- 3.3 mmol/L Trolox equivalents) found for aged wines. Three couples of experimental wines were prepared from the same grapes by traditional or carbonic maceration. These wines showed a different phenolic pattern, anthocyanins being more abundant in vini novelli. However, the average total antioxidant activities of the wines were similar, suggesting that aging (and not the wine-making technique) is the main factor influencing the antioxidant activity of red wines.

Relationship between rate and extent of catechin absorption and plasma antioxidant status.

Flavonoids are described to exert a large array of biological activities, which are mostly ascribed to their radical-scavenging, metal chelating and enzyme modulation ability. Most of these evidences have been obtained by in vitro studies on individual compounds and at doses largely exceeding those dietary. Little is known about a possible relationship between rate and extent of the absorption and modifications of plasma antioxidants. To elucidate this aspect, human volunteers were supplemented with single doses of green tea catechins in free (Greenselect) or phospholipid complex form (Greenselect Phytosome) equivalent to 400 mg epigallocatechingallate (EGCg). EGCg was chosen as biomarker for green tea catechin absorption, and its time course plasma concentration was correlated to the subsequent percent variations of plasma ascorbate, total glutathione, alpha-tocopherol, beta-carotene and Total Radical Antioxidant Parameter (TRAP). Green tea catechins were absorbed more extensively when administered as phospholipid complex rather than as free catechins. Single dose intake of both forms of catechins produced a transient decrease (10-20%) of plasma ascorbate and total glutathione and an increase of plasma TRAP (16-19%). These variations were consistent with the plasmatic levels of EGCg, ascorbate and total glutathione.

Effects of moderate consumption of red wine on platelet aggregation and haemostatic variables in healthy volunteers.

OBJECTIVE: To evaluate the effect of moderate consumption of red wine on platelet aggregation and haemostatic variables, discriminating the effect of alcohol from that of non-alcoholic components. DESIGN: A randomised crossover study. SETTING: The Department of Food Science and Technology, University of Milan. SUBJECTS: Eleven healthy male volunteers who were moderate drinkers. INTERVENTIONS: For three periods of four weeks, subjects drank three different beverages [320 ml of red wine (providing 30 g/day of alcohol), 30 g/day of alcohol diluted in 320 ml of clear fruit juice or 320 ml of dealcoholised red wine] during the two main meals. Each treatment was preceded by a period of four weeks of complete withdrawal from any alcoholic beverage. At the end of each period platelet aggregation after collagen and ADP stimulus, and levels of fibrinogen, plasminogen, tissue-type plasminogen activator (t-PA) antigen and von Willebrand factor (vWF) were determined. RESULTS: Consumption for a period of four weeks of 30 g/day of alcohol either from red wine or alcohol resulted in similar decreases of collagen-induced platelet aggregation and fibrinogen levels. ADP-induced platelet aggregation, t-PA antigen, vWF and plasminogen levels were not affected by any treatment. No differences were detected when we compared platelet function and the other haemostatic variables at the end of red wine and dealcoholised treatments with findings at the end of alcohol treatment and abstinence. CONCLUSIONS: The well known positive effect of moderate consumption of red wine on haemostasis seems due to alcohol and not to the non-alcoholic fraction present in red wine.

Red wine effects on peroxidation indexes of rat plasma and erythrocytes.

Moderate wine intake has been associated with low risk for cardiovascular disease, possibly due to its polyphenol content. We investigated the influence of these compounds on peroxidative indices of blood. Forty Sprague-Dawley rats were divided into four groups given the same AIN-76 diet but different types of isocaloric beverage: red wine, alcohol and dealcoholated wine and water with added sucrose. Rats consumed about 35 ml day(-1) of beverage and 17 g day(-1) of diet for a total of about 95 kcal day(-1). Plasma alpha-tocopherol was higher in the alcohol group and the peroxidation kinetic slope was higher in the control and dealcoholated wine groups. Ascorbic acid in whole blood was higher in the alcohol group than the others. Erythrocytic glutathione peroxidase activity was lower in the red wine group. The other variables studied, were not significantly different in the four groups. Despite the significant differences observed, the oxidative status of blood does not appear seriously altered by heavy ingestion of wine and thus of polyphenols. Probably the balanced diet and adequate intake of micronutrients were sufficient to counteract any oxidative damage.

Effect of red wine consumption on rat liver peroxidation.

To evaluate the role of wine polyphenols and that of alcohol on lipid peroxidation indexes and membrane composition in the liver, 40 Sprague-Dawley rats were fed for 28 days with a commercial AIN-76 diet to which was added one of four different beverages: red wine, alcohol solution, dealcoholated wine, or water. The beverage provided 26% of the caloric intake. Peroxidation indexes and antioxidative enzymes were determined: no significant differences were detected in catalase and glutathione peroxidase whereas superoxide dismutase was significantly lower in the wine-treated animals (220.3 +/- 15.4 vs. 342.2 +/- 43.0 U/mg protein of controls). The following significant differences in hepatic variables were observed: increased alpha-tocopherol concentration in the alcohol group (0.17 +/- 0.02 vs. 0.11 +/- 0.01 microgram/mg protein of controls); increased concentration of cytochrome P450 in the rats given wine (0.75 +/- 0.06 vs. 0.51 +/- 0.08 nmol/mg protein of the alcohol group); increased concentration of cytochrome b5 in wine and dealcoholated wine treatment groups (0.30 +/- 0.01 vs. 0.23 +/- 0.02 nmol/mg protein of controls). The liver membrane fatty acid composition of the wine and dealcoholated wine groups was similar and showed an increase in the saturated fatty acid percentage and a decrease in the polyunsaturated one. The data presented indicate that the main action of polyphenols seems to be an induction of cytochrome activity and that the modality of red wine administration adopted combined with an adequate diet does not provoke any apparent physiological effect on the animals.

Evaluation of the effect of alcohol consumption on erythrocyte lipids and vitamins in a healthy population.

There is epidemiological evidence that a moderate consumption of alcohol could reduce coronary heart disease. To corroborate this statement and to see how the consumption of red wine affects phospholipid and fatty acid patterns and antioxidant status, a survey was conducted on 58 adult males (20-75 years old). A questionnaire was used to discover their medical history, various constitutional and life-style factors, food habits, and nutrient intake; and the type and amount of alcoholic intake were investigated by means of a questionnaire. Subjects were divided into two groups of nondrinkers and average drinkers (mean 46.5 +/- 4.4, range 30.2-63.4 g/day), and the effect of alcohol was made on the following variables: gamma-glutamyltranspeptidase, apolipoprotein AI, apolipoprotein B, total and high-density lipoprotein-cholesterol, triglycerides, and antioxidant vitamins were determined in plasma; and phospholipids the fatty acids of phosphatidylcholine (PC) and phosphatidylethanolamine total cholesterol, alpha-tocopherol, beta-carotene, and retinol were determined in red blood cells (RBCs). There were no significant differences between the two groups in protein, fat, carbohydrate, retinol equivalent, alpha-tocopherol content, and cholesterol/saturated fat index of their diet. Analysis of the plasma levels of biochemical variables--adjusted for age, smoking (number of cigarettes/day), and body mass index--showed a significant increase of gamma-glutamyltranspeptidase and apolipoprotein AI concentration in the average drinkers compared with nondrinkers. Plasma alpha-tocopherol and retinol levels were also significantly higher in average drinkers. In the latter group, ANCOVA demonstrated a lower percentage of sphingomyelin in RBCs, with a lower sphingomyelin/PC ratio.(ABSTRACT TRUNCATED AT 250 WORDS)