Red wine does not reduce mature atherosclerosis in apolipoprotein E-deficient mice.
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BACKGROUND: Red wine polyphenols and ethanol reduce fatty streak formation (early atherosclerosis) in various animal models. These experimental results support the observation that alcoholic beverages protect against myocardial infarction in humans. However, fatty streaks may not reflect the pathology of mature and clinically relevant atherosclerosis. The present study examined the effects of red wine polyphenols and ethanol on mature atherosclerosis in apolipoprotein E-deficient mice. METHODS AND RESULTS: Eighty-four 7-week-old mice were randomized to receive water, red wine (diluted to 6% ethanol v/v), 6% ethanol v/v, or red wine powder in water. All mice were fed a normal chow diet. At 26 weeks of age, the mice were killed. HDL cholesterol was raised 12.0% (95% CI, 4.0% to 20.0%) and 9.2% (95% CI, 1.5% to 16.9%) by red wine and ethanol, respectively. At the end of study, all mice exhibited advanced atherosclerosis in the aortic bulb, whereas less mature atherosclerosis predominated in the brachiocephalic trunk. The amount of atherosclerosis in the aortic bulb and the brachiocephalic trunk were similar in all groups (P:=0.92 and P:=0.14, respectively). To evaluate whether ethanol or red wine polyphenols were protective by stabilizing atherosclerotic plaques rather than reducing their size, we measured the percentage of collagen-poor areas in left coronary sinus plaques as a morphological criterion of plaque stability. The percentage of collagen-poor areas did not differ between groups (P:=0.71). CONCLUSIONS: Neither ethanol nor red wine polyphenols reduced mature atherosclerosis or changed the content of collagen in plaques in apolipoprotein E-deficient mice. (+info)
Growth and arginine metabolism of the wine lactic acid bacteria Lactobacillus buchneri and Oenococcus oeni at different pH values and arginine concentrations.
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During malolactic fermentation (MLF) in grape must and wine, heterofermentative lactic acid bacteria may degrade arginine, leading to the formation of ammonia and citrulline, among other substances. This is of concern because ammonia increases the pH and thus the risk of growth by spoilage bacteria, and citrulline is a precursor to the formation of carcinogenic ethyl carbamate (EC). Arginine metabolism and growth of Lactobacillus buchneri CUC-3 and Oenococcus oeni strains MCW and Lo111 in wine were investigated. In contrast to L. buchneri CUC-3, both oenococci required a higher minimum pH for arginine degradation, and arginine utilization was delayed relative to the degradation of malic acid, the main aim of MLF. This allows the control of pH increase and citrulline formation from arginine metabolism by carrying out MLF with pure oenococcal cultures and inhibiting cell metabolism after malic acid depletion. MLF by arginine-degrading lactobacilli should be discouraged because arginine degradation may lead to the enhanced formation of acids from sugar degradation. A linear relationship was found between arginine degradation and citrulline excretion rates. From this data, strain-specific arginine-to-citrulline conversion ratios were calculated that ranged between 2.2 and 3.9% (wt/wt), and these ratios can be used to estimate the contribution of citrulline to the EC precursor pool from a given amount of initial arginine. Increasing arginine concentrations led to higher rates of growth of L. buchneri CUC-3 but did not increase the growth yield of either oenococcus. These results suggest the use of non-arginine-degrading oenococci for inducing MLF. (+info)
Sensorimotor and physiological effects of various alcoholic beverages.
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Effects of a standard dose of alcohol (1.3 g/kg) in the form of Canadian rye whisky, Canadian beer and a sparkling table wine were compared with those of a nonalcoholic carbonated control beverage. Sixteen young male and eight female subjects, all moderate drinkers, were tested in a Latin square design. Measurements were made on the pursuit rotor and quantitative Romberg tests, and of skin temperature, heart rate, malar flush and blood alcohol concentration during the prealcohol baseline period and at regular intervals over the 4-hour drinking period. The three alcoholic beverages produced blood alcohol curves that did not differ significantly. All three alcoholic beverages produced increasing sensorimotor impairment over time, which corresponded in degree to the increasing blood alcohol concentration. There were no significant differences between the three beverages on either the sensorimotor or physiological measures at any blood alcohol value. The results of this study indicate that the degree of impairment after alcohol ingestion in a socially relevant manner is not dependent on the type of beverage consumed, but only on the resulting blood alcohol concentration. (+info)
Yeast population dynamics during the fermentation and biological aging of sherry wines.
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Molecular and physiological analyses were used to study the evolution of the yeast population, from alcoholic fermentation to biological aging in the process of "fino" sherry wine making. The four races of "flor" Saccharomyces cerevisiae (beticus, cheresiensis, montuliensis, and rouxii) exhibited identical restriction patterns for the region spanning the internal transcribed spacers 1 and 2 (ITS-1 and ITS-2) and the 5.8S rRNA gene, but this pattern was different, from those exhibited by non-flor S. cerevisiae strains. This flor-specific pattern was detected only after wines were fortified, never during alcoholic fermentation, and all the strains isolated from the velum exhibited the typical flor yeast pattern. By restriction fragment length polymorphism of mitochondrial DNA and karyotyping, we showed that (i) the native strain is better adapted to fermentation conditions than commercial strains; (ii) two different populations of S. cerevisiae strains are involved in the process of elaboration, of fino sherry wine, one of which is responsible for must fermentation and the other, for wine aging; and (iii) one strain was dominant in the flor population integrating the velum from sherry wines produced in Gonzalez Byass wineries, although other authors have described a succession of races of flor S. cerevisiae during wine aging. Analyzing all these results together, we conclude that yeast population dynamics during biological aging is a complex phenomenon and differences between yeast populations from different wineries can be observed. (+info)
Purification and characterization of an beta-D-xylosidase from Candida utilis IFO 0639.
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An intracellular beta-D-xylosidase from Candida utilis IFO 0639 was purified to homogeneity through four chromatographic steps. The molecular mass of the enzyme was estimated to be 92 kDa by SDS-PAGE. The enzyme had an isoelectric point at 5.6, and was most active at pH 6.0 and at around 40 degrees C. Ethanol at an optimal concentration (10%, v/v) stimulated the initial enzyme activity by 57%. D-Xylose, the product of the beta-D-xylosidase, has no effect on the enzyme activity at 300 mM. The beta-D-xylosidase was highly specific to the beta-D-xylopyranoside configuration. The enzyme hydrolyzed beta-1,4-linked xylo-oligosaccharides with chain lengths from 2 to 5 by releasing xylose from the non-reducing end. It showed no activity against xylan. The enzyme efficiently released monoterpenols from an aroma precursor extracted from Muscat grape juice. The fermentation of Muscat juice coupled with the enzyme addition produced a small increase in the concentration of monoterpenols. (+info)
Lead poisoning from homemade wine: a case study.
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A 66-year-old man suffered the symptoms of severe lead poisoning for 2 years before diagnosis. The man had a blood lead level (PbB) on admission to hospital of 98 microg/dL. A detailed investigation revealed that the poisoning occurred as a result of drinking a homemade red wine, for which analyses showed a lead concentration up to 14 mg/L--70 times the Australian maximum limit for lead in wine. The source of the lead was a highly corroded enamel bathtub in which grape crushings and juice were stored for a week prior to bottling. The corrosion of the enamel surface of the bathtub had resulted in pitted patches up to 1 mm in depth along the side of the bathtub. Powdering of the tub surface was evident below a level where wine had been in contact with the sides of the tub. The homemade wine had a pH of 3.8, which would have greatly contributed to the solubilization of metals from the glaze. We conducted a test in which commercial red wine of similar pH and containing < 0.2 mg/L lead was placed in this tub for 7 days. Subsequent testing revealed a lead level of 310 mg/L. This high lead concentration is consistent with the surface area of enamel on the bathtub being in contact with a small liquid volume as in the case of the leaching test using commercial red wine. This case study highlights the importance of the use of food-grade materials for the preparation and storage of homemade beverages or food. (+info)
Alcohol, red wine and cardiovascular disease.
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The objective of this article is to review the existing literature concerning the effects and mechanisms of action of red wine consumption vs. other alcoholic beverages on the risk of cardiovascular disease (CVD). Of particular interest is the form and quantity of alcohol consumed. This relationship between alcohol consumption and mortality is well supported by epidemiologic studies, which have suggested that different forms of alcohol alter the relative risk values for mortality from CVD. Although not without exception, current evidence from epidemiologic and experimental studies suggests a protective effect against the development of CVD with moderate consumption of red wine. The exact nature of the protective effect remains to be established. However, mechanisms including LDL oxidation and alterations in hemostatic variables are being increasingly recognized as contributory. Key components of red wine thought to be responsible for the protective effects include phenolic compounds and alcohol content. Despite the research presented, some questions relating to the current recommendations regarding moderate alcohol consumption and cardiovascular health remain. However, collectively, the literature aids in understanding some of the ways in which alcoholic beverages and their components affect the health of our population. (+info)
Moderate alcohol consumption in social drinkers raises plasma homocysteine levels: a contradiction to the 'French Paradox'?
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Evidence from observational studies suggests that elevated levels of homocysteine are associated with an increased risk of cardiovascular diseases. We assessed whether moderate alcohol intake in healthy social drinkers, suggested to be cardioprotective according to the 'French paradox', influences the cardiovascular risk factor homocysteine. A total of 60 normal nourished subjects who had no evidence of vascular disease or other risk factors for hyperhomocysteinaemia were assigned to receive mineral water or 30 g of alcohol per day (as beer, red wine or spirits) for a period of 6 weeks. Homocysteine levels of social drinkers, independent of which beverage was consumed, increased during the observation. We postulate that elevated levels of homocysteine in social drinkers with regular moderate alcohol intake are at risk of developing cardiovascular diseases, which contradicts the suggested cardioprotection of alcohol according to the 'French paradox'. (+info)