Proanthocyanidins, flavonoids exhibiting cardiovascular protection, constitute a major fraction of the flavonoid ingested in the human diet. Although they are poorly absorbed, they are metabolized by the intestinal microbiota into various phenolic acids. An analytical method, based on an optimized 96-well plate solid-phase extraction (SPE) procedure and liquid chromatography tandem mass spectrometry (SPE-LC-MS/MS) for the analysis of 19 phenolic microbial metabolites and monomeric and dimeric flavanols in urine samples, was developed and validated. Human urine samples were obtained before and after ingestion of an acute consumption of 40 g of soluble cocoa powder and rat urines before and after the prolonged administration (2 weeks) of different diets composed of natural cocoa powder. The mean recovery of analytes using the new SPE-LC-MS/MS method ranged from 87% to 109%. Accuracy ranged from 87.5% to 113.8%, and precision met acceptance criteria (<15% relative standard deviation). Procyanidin B2 has been detected and quantified for the first time in human and rat urine after cocoa consumption. Changes in human and rat urinary levels of microbial phenolic acids and flavanols were in the range of 0.001-59.43 nmol/mg creatinine and of 0.004-181.56 nmol/mg creatinine, respectively. Major advantages of the method developed include reduction of laboratory work in the sample preparation step by the use of 96-well SPE plates and the sensitive measurement of a large number of metabolites in a very short run time, which makes it ideal for use in epidemiological studies.

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These results suggest that the intake of cocoa polyphenols may modulate inflammatory mediators in patients at high risk of cardiovascular disease. These antiinflammatory effects may contribute to the overall benefits of cocoa consumption against atherosclerosis. This trial was registered in the Current Controlled Trials at London, International Standard Randomized Controlled Trial Number, at controlled-trials.com as ISRCTN75176807.

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.

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BackgroundThe economic boom in Saudi Arabia indirectly prompted the use of dietary supplements in the last two decades. Our aim is to investigate the prevalence of dietary supplement use and its association with sociodemographic/lifestyle characteristics among Saudi female students.MethodsIn this cross-sectional study, 534 female participants (≥19 years of age) completed a self-administered questionnaire that include sociodemographic and lifestyle characteristics, perceived health status, dietary supplement use, general awareness, attitudes and behavior.ResultsIn all participants, the prevalence of dietary supplement use was 76.6% (n = 409). High level of education (p = 0.002) and more physical activity (p = 0.008) exhibited a significant positive association with users than to non-users. The frequency showed that beta-carotene (54.2%), chamomile (54.2%), and glucosamine (53.8%) were the most preferred diet supplements under the category “when needed”. Cod liver oil (71.3%), omega 3 (68.3%), multi-vitamins (61.5%), ginseng (60%), and vitamin A (60%), were mostly used “from time to time”. Multi-minerals (34.4%) were the preferred choice when it comes to daily use. The main reasons for supplement use were to “maintain healthy hair” and “injury and illness” (both 26.2%). About 38.4% were not aware and 30.3% disagree on differences taking supplements with or without consulting a medical professional. About 36.7% lack information about side effects while, 35.0% were unaware about any health effect of dietary supplements.ConclusionThe prevalence of dietary supplement use was high in Saudi female students and was significantly associated with sociodemographic and lifestyle factors.

Epidemiological studies have demonstrated the beneficial effect of plant-derived food intake in reducing the risk of cardiovascular disease (CVD). The potential bioactivity of cocoa and its polyphenolic components in modulating cardiovascular health is now being studied worldwide and continues to grow at a rapid pace. In fact, the high polyphenol content of cocoa is of particular interest from the nutritional and pharmacological viewpoints. Cocoa polyphenols are shown to possess a range of cardiovascular-protective properties, and can play a meaningful role through modulating different inflammatory markers involved in atherosclerosis. Accumulated evidence on related anti-inflammatory effects of cocoa polyphenols is summarized in the present review.

Oligomers and polymers of flavan-3-ols (proanthocyanidins) are very abundant in the Mediterranean diet, but are poorly absorbed. However, when these polyphenols reach the colon, they are metabolised by the intestinal microbiota into various phenolic acids, including phenylpropionic, phenylacetic and benzoic acid derivatives. Since the biological properties of these metabolites are not completely known, in the present study, we investigated the effect of the following microbial phenolic metabolites: 3,4-dihydroxyphenylpropionic acid (3,4-DHPPA), 3-hydroxyphenylpropionic acid, 3,4-dihydroxyphenylacetic acid (3,4-DHPAA), 3-hydroxyphenylacetic acid, 4-hydroxybenzoic acid and 4-hydroxyhippuric acid (4-HHA), on modulation of the production of the main pro-inflammatory cytokines (TNF-a, IL-1b and IL-6). The production of these cytokines by lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMC) pre-treated with the phenolic metabolites was studied in six healthy volunteers. With the exception of 4-HHA for TNF-a secretion, only the dihydroxylated compounds, 3,4-DHPPA and 3,4-DHPAA, significantly inhibited the secretion of these pro-inflammatory cytokines in LPS-stimulated PBMC. Mean inhibition of the secretion of TNF-a by 3,4-DHPPA and 3,4-DHPAA was 84·9 and 86·4 %, respectively. The concentrations of IL-6 in the culture supernatant were reduced by 88·8 and 92·3 % with 3,4-DHPPA and 3,4-DHPAA pre-treatment, respectively. Finally, inhibition was slightly higher for IL-1b, 93·1 % by 3,4-DHPPA and 97·9 % by 3,4-DHPAA. These results indicate that dihydroxylated phenolic acids derived from microbial metabolism present marked anti-inflammatory properties, providing additional information about the health benefits of dietary polyphenols and their potential value as therapeutic agents.