Mireia Urpi-Sarda

Flavanol and Flavonol Contents of Cocoa Powder Products : Influence of the Manufacturing Process

Major brands of cocoa powder products present in the Spanish market were analyzed for monomeric flavanols [(+)-catechin and (-)-epicatechin] and flavonols [quercetin-3-glucuronide, quercetin-3-glucoside (isoquercitrin), quercetin-3-arabinoside, and quercetin]. In addition, the influence of the manufacturing process of cocoa powder products, in particular, the alkalinization treatment ( Dutching), on the original content of these flavonoids has been studied. (-)-Epicatechin was in the range of 116.02-730.26 microg/g, whereas (+)-catechin was in the range of 81.40-447.62 microg/g in the commercial cocoa products studied. Among flavonols, quercetin-3-arabinoside and isoquercitrin were the major flavonols in the cocoa powder products studied, ranging from 2.10 to 40.33 microg/g and from 3.97 to 42.74 microg/g, respectively, followed by quercetin-3-glucuronide (0.13-9.88 microg/g) and quercetin aglycone (0.28-3.25 microg/g). To our knowledge, these results are the first quantitative data in relation to the content of individualized flavonol derivatives in commercial cocoa powder products. The alkalinization treatment resulted in 60% loss of the mean total flavonoid content. Among flavanols, (-)-epicatechin presented a larger decline (67%, as a mean percentage difference) than (+)-catechin (38%), probably because of its epimerization into (-)-catechin, a less bioavailable form of catechin. A decline was also confirmed for di-, tri-, and tetrameric procyanidins. In the case of flavonols, quercetin presented the highest loss (86%), whereas quercetin-3-glucuronide, quercetin-3-arabinoside, and isoquercitrin showed a similar decrease (58, 62, and 61%, respectively). It is concluded that the large decrease found in the flavonoid content of natural cocoa powder, together with the observed change in the monomeric flavanol profile that results from the alkalinization treatment, could affect the antioxidant properties and the polyphenol biovailability of cocoa powder products.

Dealcoholized Red Wine Decreases Systolic and Diastolic Blood Pressure and Increases Plasma Nitric Oxide

Rationale: Experimental studies have shown a potential blood pressure (BP) lowering effect of red wine polyphenols, whereas the effects of ethanol and polyphenols on BP in humans are not yet clear. Objective: The aim of the present work was to evaluate the effects of red wine fractions (alcoholic and nonalcoholic) on BP and plasma nitric oxide (NO) in subjects at high cardiovascular risk. Methods and Results: Sixty-seven men at high cardiovascular risk were studied. After a 2-week run-in period, subjects were randomized into 3 treatment periods in a crossover clinical trial, with a common background diet plus red wine (30g alcohol/day), the equivalent amount of dealcoholized red wine, or gin (30g alcohol/day), lasting 4 weeks each intervention. At baseline and after each intervention, anthropometrical parameters, BP and plasma NO were measured. Systolic and diastolic BP decreased significantly after the dealcoholized red wine intervention and these changes correlated with increases in plasma NO. Conclusions: Dealcoholized red wine decreases systolic and diastolic BP. Our results point out through an NO-mediated mechanism. The daily consumption of dealcoholized red wine could be useful for the prevention of low to moderate hypertension. Trial registered at controlled-trials.com: ISRCTN88720134.

Contribution of Bioactive Foods and Their Emerging Role in Immunomodulation, Inflammation, and Arthritis

Bioactive food components among which polyphenols are the most widely distributed groups exhibit the capacity to influence the immune system and modulate several metabolic processes allowing for beneficial effects in diseases like inflammation and arthritis.

Reply to Iqbal and Kazory

We thank Drs Iqbal and Kazory1 for their interest in our work and appreciate the concerns raised in their letter to address them in future studies. Regarding the usefulness of office measurement of blood pressure (BP) in the detection of changes in BP in intervention studies, measurement of office BP is considered a reliable method according to the guidelines for management of arterial hypertension in a clinical setting2 and it has been useful in large clinical trials.3 To uniform the BP recordings in our study, a fixed preplanned interval between beverage intake and BP measurement was established (12 hours), as volunteers were asked to come at the same hour after each intervention period and were also asked to maintain their dietary pattern (ie, meal times) throughout the study, emphasizing the fact that the last week of the 1-month intervention was the most important in maintaining this pattern to avoid variability in the BP measurements. The biphasic impact of acute and repeated alcohol intake is a matter of interest, but …