Pedro Mena

Bioavailability, bioactivity and impact on health of dietary flavonoids and related compounds: an update.

There is substantial interest in the role of plant secondary metabolites as protective dietary agents. In particular, the involvement of flavonoids and related compounds has become a major topic in human nutrition research. Evidence from epidemiological and human intervention studies is emerging regarding the protective effects of various (poly)phenol-rich foods against several chronic diseases, including neurodegeneration, cancer and cardiovascular diseases. In recent years, the use of HPLC–MS for the analysis of flavonoids and related compounds in foods and biological samples has significantly enhanced our understanding of (poly)phenol bioavailability. These advancements have also led to improvements in the available food composition and metabolomic databases, and consequently in the development of biomarkers of (poly)phenol intake to use in epidemiological studies. Efforts to create adequate standardised materials and well-matched controls to use in randomised controlled trials have also improved the quality of the available data. In vitro investigations using physiologically achievable concentrations of (poly)phenol metabolites and catabolites with appropriate model test systems have provided new and interesting insights on potential mechanisms of actions. This article will summarise recent findings on the bioavailability and biological activity of (poly)phenols, focusing on the epidemiological and clinical evidence of beneficial effects of flavonoids and related compounds on urinary tract infections, cognitive function and age-related cognitive decline, cancer and cardiovascular disease.

Rapid and Comprehensive Evaluation of (Poly)phenolic Compounds in Pomegranate (Punica granatum L.) Juice by UHPLC-MSn

The comprehensive identification of phenolic compounds in food and beverages is a crucial starting point for assessing their biological, nutritional, and technological properties. Pomegranate (Punica granatum L.) has been described as a rich source of (poly)phenolic components, with a broad array of different structures (phenolic acids, flavonoids, and hydrolyzable tannins) and a quick, high throughput, and accurate screening of its complete profile is still lacking. In the present work, a method for UHPLC separation and linear ion trap mass spectrometric (MSn) characterization of pomegranate juice phenolic fraction was optimized by comparing several different analytical conditions. The best solutions for phenolic acids, anthocyanins, flavonoids, and ellagitannins have been delineated and more than 70 compounds have been identified and fully characterized in less than one hour total analysis time. Twenty-one compounds were tentatively detected for the first time in pomegranate juice. The proposed fingerprinting approach could be easily translated to other plant derived food extracts and beverages containing a wide array of phytochemical compounds.

Environmental impact of omnivorous, ovo-lacto-vegetarian, and vegan diet

Food and beverage consumption has a great impact on the environment, although there is a lack of information concerning the whole diet. The environmental impact of 153 Italian adults (51 omnivores, 51 ovo-lacto-vegetarians, 51 vegans) and the inter-individual variability within dietary groups were assessed in a real-life context. Food intake was monitored with a 7-d dietary record to calculate nutritional values and environmental impacts (carbon, water, and ecological footprints). The Italian Mediterranean Index was used to evaluate the nutritional quality of each diet. The omnivorous choice generated worse carbon, water and ecological footprints than other diets. No differences were found for the environmental impacts of ovo-lacto-vegetarians and vegans, which also had diets more adherent to the Mediterranean pattern. A high inter-individual variability was observed through principal component analysis, showing that some vegetarians and vegans have higher environmental impacts than those of some omnivores. Thus, regardless of the environmental benefits of plant-based diets, there is a need for thinking in terms of individual dietary habits. To our knowledge, this is the first time environmental impacts of three dietary regimens are evaluated using individual recorded dietary intakes rather than hypothetical diet or diets averaged over a population.

Ultra-HPLC–MSn (Poly)phenolic Profiling and Chemometric Analysis of Juices from Ancient Punica granatum L. Cultivars: A Nontargeted Approach

This study deals with the qualitative characterization of the phenolic profile of pomegranate juices obtained from ancient accessions. Composition data, together with genetic, morphological, and agronomical parameters, may lead to a full characterization of such germplasm, with the aim of its retrieval and biodiversity valorization. Environmental adaptation, indeed, may contribute to an enrichment of the phenolic content in pomegranate, with important effects on its nutritional properties. More than 65 punicalagins, ellagic acid derivatives, flavonoids, anthocyanins, and phenylpropanoids were simultaneously detected from four centuries old Punica granatum L. ecotypes from northern Italy and compared with those of P. granatum cv. Dente di Cavallo, a widely cultivated Italian cultivar, using a simple ultra-HPLC (uHPLC) separation and MS(n) linear ion trap mass spectrometric characterization. Fingerprinting phytochemical discrimination of the accessions was obtained by chemometric analysis despite their limited geographical distribution, confirming the great intraspecific variability in pomegranate secondary metabolism. The combined recourse to uHPLC-MS(n) qualitative fingerprinting and multivariate analysis may represent a useful tool for the discrimination and selection of pomegranate germplasm with specific properties related to polyphenolic content.

Brassica Foods as a Dietary Source of Vitamin C: A Review

Brassica genus includes known horticultural vegetables with major economical importance worldwide, and involves vegetables of economical importance being part of the diet and source of oils for industry in many countries. Brassicales own a broad array of health-promoting compounds, emphasized as healthy rich sources of vitamin C. The adequate management of pre- and postharvest factors including crop varieties, growth conditions, harvesting, handling, storage, and final consumer operations would lead to increase or preserve of the vitamin C content or reduced losses by interfering in the catalysis mechanisms that remains largely unknown, and should be reviewed. Likewise, the importance of the food matrix on the absorption and metabolism of vitamin C is closely related to the range of the health benefits attributed to its intake. However, less beneficial effects were derived when purified compounds were administered in comparison to the ingestion of horticultural products such as Brassicas, which entail a closely relation between this food matrix and the bioavailability of its content in vitamin C. This fact should be here also discussed. These vegetables of immature flowers or leaves are used as food stuffs all over the world and represent a considerable part of both western and non-Western diets, being inexpensive crops widely spread and reachable to all social levels, constituting an important source of dietary vitamin C, which may work synergistically with the wealth of bioactive compounds present in these foods.

Sustained deficit irrigation affects the colour and phytochemical characteristics of pomegranate juice

BACKGROUND No information exists on the consequences of water stress on the pomegranate (Punica granatum L.) tree in terms of the quality and health/nutritional properties of its juice. In this study the influence of two different sustained deficit irrigation treatments on the colour, antioxidant activity and total phenolic compound, total anthocyanin, punicalagin and ellagic acid contents of pomegranate juice was assessed. RESULTS Control plants were irrigated at 75% ETo (crop reference evapotranspiration) in order to ensure non-limiting soil water conditions, while others were subjected to sustained deficit irrigation at 43 and 12% ETo throughout the experimental period. Both moderate (43%) and severe (12%) water stress treatments led to pomegranate juices with a more yellowish colour, lower antioxidant activity and lower total phenolic compound, punicalagin and total anthocyanin contents than those from control plants. CONCLUSION Pomegranate juice from trees under sustained deficit irrigation was of lower quality and less healthful than that from trees without water stress. From a nutritional point of view, this means that a reduction in irrigation provides a dramatic decrease in bioactive phenolic compounds, especially anthocyanins and punicalagin, and consequently a lower visual attraction of the juice owing to the weak red colour of the fruit.

Flavan‐3‐ols, anthocyanins, and inflammation

The process of inflammation constitutes a reactive response of the organism to tissue damage and is an important factor making part of a number of degenerative pathologies as insulin resistance, dyslipidemia, and hypertension, all of them comprised in the metabolic syndrome. There is an increasing interest in plant products rich in flavan‐3‐ols and anthocyanins because of their potential beneficial effects observed in epidemiological studies against inflammatory‐related diseases. Their anti‐inflammatory effects are exerted by modulation of cell redox status and inhibition of signaling pathways as NF‐κB activation. The effects depend on their concentrations in target tissues and hence the bioavailability pathways followed by each particular compound. In this sense, in vitro studies performed with parental compounds at doses exceeding to those found in vivo may be drawing erroneous conclusions about their real efficacy. Contradictory results have been observed in human intervention trials, which may be ascribed to the type of population studied, length of study, source of flavan‐3‐ol/anthocyanin, and dose provided. Human studies are required to confirm the positive effects found in vitro and in animal models. Future research should be focused on the understanding of dose/flavonoid intake–response relationship with pharmacokinetic studies, evaluating proper biomarkers of intake. Long‐term dietary interventions are necessary to observe effects on markers of late activation as well as the possible preventive effects of these compounds on long‐term inflammation‐related diseases.

Assessment of pomegranate wine lees as a valuable source for the recovery of (poly)phenolic compounds

Wine lees are the residue formed at the bottom of recipients containing wine after fermentation and are mainly composed of yeast. They can be applied for the recovery of value-added phytochemicals owing to the ability of yeast to form molecular interactions with (poly)phenolic compounds. This study aimed to evaluate the potential use of lees obtained as by-products after winemaking of pomegranate (Punica granatum L.) juice. Pomegranate wine lees showed high both phenolic content (about 30 mg GAE/g dry matter) and antioxidant capacity by DPPH and ABTS(+) assays. The phytochemical screening of this by-product by UHPLC-ESI-MS(n) allowed the identification of up to 39 chemicals, being hydrolysable tannins and anthocyanins the predominant structures. Ellagic acid and gallic acid were present in high amounts. In addition, mineral composition was also assessed. Overall, pomegranate wine lees resulted in a promising source for the recovery of bioactive polyphenols with potential applications in different industrial fields.

Evaluation of sensorial, phytochemical and biological properties of new isotonic beverages enriched with lemon and berries during shelf life

BACKGROUND The aim of this work was to design new isotonic drinks with lemon juice and berries: maqui (Aristotelia chilensis (Molina) Stuntz), açaí (Euterpe oleracea Mart.) and blackthorn (Prunus spinosa L.), following previous research. Quality parameters, sensorial attributes, antioxidant activities (ABTS(+), DPPH(•) and O2(•-) assays) and biological capacities (α-glucosidase and lipase inhibitory assays) were evaluated over 70 days of shelf-life period. RESULTS Maqui isotonic blends were the most active in all antioxidant assays (8.35 and 3.07 mmol L(-1) Trolox for ABTS(+) and DPPH(•)), in the lipase inhibitory assay (43.19 U L(-1)), and showed the highest total phenol content by the Folin-Ciocalteu test (80.97 mg 100 mL(-1) gallic acid), as a result of its higher content of total anthocyanins (42.42 mg 100 mL(-1)). Berry mixtures were also the most potent inhibitors of α-glucosidase between all samples, and displayed an attractive red colour and good sensorial attributes. CONCLUSIONS All the studied parameters remained quite stable during preservation, in general, and the new isotonic drinks can be useful to equilibrate redox balance in acute and intense exercise, and support weight loss programmes, avoiding triglyceride absorption and hyperglycaemia involved in obesity and diabetes mellitus, respectively. Further research in vivo is necessary to verify their beneficial effects for sports, nutrition and health.

New Beverages of Lemon Juice with Elderberry and Grape Concentrates as a Source of Bioactive Compounds

UNLABELLED Considering the health potential of lemon and berry fruits, different functional beverages rich in antioxidant phytochemicals, which demonstrated beneficial effects, were developed. To fulfill this objective, lemon juice was combined with 2 different concentrates, elderberry and grape, in a proportion of 5% (w/v). Bioactive composition (flavonoids and vitamin C) and color stability, as well as the antioxidant capacity of mixtures, during a period of 56 d of storage, were studied. A protective role of anthocyanins on ascorbic acid preservation was noted for both lemon-berry blends, keeping vitamin C stable until the end of the storage. In addition, the new drink combining lemon and elderberry performed better than the grape-lemon mixture in terms of health-promoting phytochemicals content, just as in vitro antioxidant capacity and color characteristics. PRACTICAL APPLICATION Beverages made from lemon juice and berries could contribute to develop new drinks with a prolonged preservation of bioactive compounds throughout storage, keeping an attractive color and a high antioxidant activity during long periods of time. The information obtained in the present work is in agreement to the rules of health and safety for juices established by the Directive of European Commission Dir2001/112/CE incorporated to the Spanish law through the RD1050/2003 regulation. Consequently, an improved performance of industrial products would be achieved.