Pérez-Jiménez, J., V. Neveu, F. Vos, A. Scalbert, 2010. Identification of the 100 richest dietary sources of polyphenols: an application of the Phenol-Explorer database. European Journal of Clinical Nutrition. 64: S112–S120.
Background/Objectives: The diversity of the chemical structures of dietary polyphenols makes it difficult to estimate their total content in foods, and also to understand the role of polyphenols in health and the prevention of diseases. Global redox colorimetric assays have commonly been used to estimate the total polyphenol content in foods. However, these assays lack specificity. Contents of individual polyphenols have been determined by chromatography. These data, scattered in several hundred publications, have been compiled in the Phenol-Explorer database. The aim of this paper is to identify the 100 richest dietary sources of polyphenols using this database. Subjects/Methods: Advanced queries in the Phenol-Explorer database (www.phenol-explorer.eu) allowed retrieval of information on the content of 502 polyphenol glycosides, esters and aglycones in 452 foods. Total polyphenol content was calculated as the sum of the contents of all individual polyphenols. These content values were compared with the content of antioxidants estimated using the Folin assay method in the same foods. These values were also extracted from the same database. Amounts per serving were calculated using common serving sizes. Results: A list of the 100 richest dietary sources of polyphenols was produced, with contents varying from 15 000mg per 100g in cloves to 10mg per 100 ml in rose´ wine. The richest sources were various spices and dried herbs, cocoa products, some darkly coloured berries, some seeds (flaxseed) and nuts (chestnut, hazelnut) and some vegetables, including olive and globe artichoke heads. A list of the 89 foods and beverages providing more than 1mg of total polyphenols per serving was established. A comparison of total polyphenol contents with antioxidant contents, as determined by the Folin assay, also showed that Folin values systematically exceed the total polyphenol content values. Conclusions: The comprehensive Phenol-Explorer data were used for the first time to identify the richest dietary sources of polyphenols and the foods contributing most significantly to polyphenol intake as inferred from their content per serving.
Razquin, C., J.A. Martínez, M.A. Martínez-González, J. Salas-Salvadó, R. Estruch, A. Marti, 2010. A 3-year Mediterranean-style dietary intervention may modulate the association between adiponectin gene variants and body weight change. Eur J Nutr. 49(5):311-9.
Purpose Adiponectin gene variations have been associated with obesity. There are few interventional studies analyzing this association. The aim of this study was to analyze the effects of a nutritional intervention with Mediterranean-style diet and three (-4034A/C, +45T/G, and +276 G/T) adiponectin gene variants on 3-year body weight changes in high cardiovascular risk patients. Subjects and methods A total of 737 participants, aged 55–80 at high cardiovascular risk were assigned to a low-fat diet or to a Mediterranean-style diet (MD) groups, one with high intake of virgin olive oil (VOO) and the other with high intake of nuts. Anthropometric parameters were taken at baseline and after 3-year follow-up, and the genotyping of the -4034A/C, +45T/G, and +276 G/T polymorphisms was done. Results GG genotype of the +45T/G polymorphism was associated with 3-year higher body weight gain (B = 1.399; B = 0.043). TT genotype of the +276G/T polymorphism was linked to the highest 3-year body weight gain in men. Both Mediterranean diets appeared to reverse this effect (p for interaction = 0.053). Conclusion Adiponectin gene variation appeared to be associated with 3-year body weight changes in a high cardiovascular risk population. This association may be modulated by a nutritional intervention with a Mediterranean-style diet.
Ros, E., L.C. Tapsell, J. Sabaté, 2010. Nuts and berries for heart health. Curr Atheroscler Rep. 12:397–406.
Nuts are nutrient-dense foods with complex matrices rich in unsaturated fatty acids and other bioactive compounds, such as L-arginine, fiber, minerals, tocopherols, phytosterols, and polyphenols. By virtue of their unique composition, nuts are likely to beneficially impact heart health. Epidemiologic studies have associated nut consumption with a reduced incidence of coronary heart disease in both genders and diabetes in women. Limited evidence also suggests beneficial effects on hypertension and inflammation. Interventional studies consistently show that nut intake has a cholesterol-lowering effect and there is emerging evidence of beneficial effects on oxidative stress, inflammation, and vascular reactivity. Blood pressure, visceral adiposity, and glycemic control also appear to be positively influenced by frequent nut consumption without evidence of undue weight gain. Berries are another plant food rich in bioactive phytochemicals, particularly flavonoids, for which there is increasing evidence of benefits on cardiometabolic risk that are linked to their potent antioxidant power.
Jalali-Khanabadi, B-A., H. Mozaffari-Khosravi, N. Parsaeyan, 2010. Effects of almond dietary supplementation on coronary heart disease lipid risk factors and serum lipid oxidation parameters in men with mild hyperlipidemia. The Journal of Alternative and Complementary Medicine. 16(12):1–5.
Objectives: Oxidation and level of plasma lipids are closely implicated in the development of coronary heart disease (CHD). Dietary almond supplementation may participate in beneficial effects on CHD lipid risk factor levels and their susceptibility to oxidative modification. The aim of this study was to evaluate the effects of dietary supplementation with almond on serum lipid levels and their relation to lipid oxidation parameters in men with mild hyperlipidemia. Design: Thirty (30) healthy volunteer men (age 45.57 ± 7.14 years and body–mass index 24.29 ± 2.15 g/m2) with mild hyperlipidemia received 60 g almond daily for 4 weeks. Outcome measures: Overnight fasting blood samples were obtained before and after supplementation. Serum levels of lipids, lipoproteins, and apolipoproteins and copper-induced serum lipid oxidation were determined. Lipid oxidation was followed by monitoring of the change of conjugated dienes in diluted serum after addition of Cu2+. A number of quantitative parameters including lag-time, maximal rate of oxidation (V-max), and maximal amount of lipid peroxide products (OD-max) were evaluated. Results: After 4 weeks, almond supplementation significantly decreased low-density lipoprotein cholesterol, total cholesterol (TC), and apolipoprotein B100 (apo-B100). At baseline, there was little correlation between lipid risk factors and lipid oxidation parameters, but a positive correlation was observed between TC and lag-time (r = 0.6, p = 0.001), negative correlation between TC with V-max and OD-max (r = -0.65, p<0.001 and r = -0.61, p = 0.001), and also positive correlation between apo-B100 with V-max and OD-max (r = 0.48, p = 0.01 and R = 0.54, p = 0.003) after almond supplementation. Conclusions: These results demonstrated that almond supplementation, in addition to lowering effects on serum levels of CHD lipid risk factors, may contribute to a dramatic change in the relation of lipid risk factors and susceptibility of serum lipids to oxidative modification. This may be due to the distribution of different almond phenolic antioxidants in different components of serum including nonlipoprotein molecules such as serum albumin.
Bolling, B.W., J.B. Blumberg, C.-Y.O. Chen. 2010. The influence of roasting, pasteurisation, and storage on the polyphenol content and antioxidant capacity of California almond skins. Food Chem.doi:10.1016/j. foodchem.2010.05.058.
Polyphenols and antioxidant activity of skins from California almonds subjected to roasting, pasteurisation, and storage were determined by LC-MS quantification, total phenols (TP), and ferric reducing antioxidant power (FRAP). Pasteurisation did not significantly change TP, FRAP, or flavonoids and phenolic acids (FP). Roasted almonds had 26% less TP and 34% less FRAP than raw, but equivalent FP (n = 12). Storing almonds at 4 and 23 ºC for 15 mo resulted in gradual increases in FP, up to 177% and 200%, respectively (n = 13). At 4 ºC and 15 mo, polyphenols increased 18-fold for p-hydroxybenzoic acid, whilst others were 45–200% higher compared to baseline values. Isorhamnetin-3-O-rutinoside accounted for 48% of the increase in FP. After 15 mo, FRAP and TP increased to 200% and 190% of initial values. Accelerated ageing of whole almonds increased FP content by 10% after 3 days, but TP and FRAP values were not significantly different from baseline to day 10. Thus, in almond skins, roasting decreases TP and FRAP but not FP, whilst storage for up to 15 mo doubles F
Mandalari, G., R.M. Faulks, C. Bisignano, K.W. Waldron, A. Narbad, M.S.J. Wickham. 2010. In vitro evaluation of the prebiotic properties of almond skins (Amygdalus communis L.). FEMS Microbiol. Lett.304:116-122.
In this study we investigated the potential prebiotic effect of natural (NS) and blanched (BS) almond skins, the latter being a byproduct of the almond-processing industry. A full model of the gastrointestinal tract, including in vitro gastric and duodenal digestion, followed by colonic fermentation using mixed fecal bacterial cultures, was used. Both NS and BS significantly increased the population of bifidobacteria and Clostridium coccoides/Eubacterium rectale group, resulting in a prebiotic index (3.2 for BS and 3.3 for NS) that compared well with the commercial prebiotic fructo-oligosaccharides (4.2) at a 24-h incubation. No significant differences in the proportion of gut bacteria groups and in short-chain fatty acid production were detected between NS and BS, showing that polyphenols present in almond skins did not affect bacterial fermentation. In conclusion, we have shown that dietary fiber from almond skins altered the composition of gut bacteria and almond skins resulting from industrial blanching could be used as potential prebiotics.
Mandalari, G., C. Bisignano, M. D’Arrigo, G. Ginestra, A. Arena, A. Tomaino, M.S.J. Wickham. 2010. Antimicrobial potential of polyphenols extracted from almond skins. Lett. Appl. Microbiol. 51(1):83–89.
Aims: To evaluate the antimicrobial properties of flavonoid-rich fractions derived from natural and blanched almond skins, the latter being a by-product from the almond processing industry. Methods and Results: Almond skin extracts were tested against Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, Salmonella enterica, Serratia marcescens), Gram-positive bacteria (Listeria monocytogenes, Enterococcus hirae, Staphylococcus aureus, Enterococcus durans) and the yeast Candida albicans. Almond skin fractions were found to have antimicrobial activity against L. monocytogenes and Staph. aureus in the range 250–500 µg ml-1), natural skins showing antimicrobial potential against the Gram-negative Salm. enterica. The interactions between three almond skin flavonoids were also evaluated with isobolograms. Conclusions: Pairwise combinations of protocatechuic acid, naringenin and epicatechin showed both synergistic and indifferent interactions against Salm. enterica and Staph. aureus. Antagonism was observed against L. monocytogenes with all combinations tested. Further studies need to be performed to understand the mechanisms responsible for these interactions. Significance and Impact of the Study: Almond skins are a potential source of natural antimicrobials.
Arena, A., C. Bisignano, G. Stassi, G. Mandalari, M.S.J. Wickham, G. Bisignano. 2010. Immunomodulatory and antiviral activity of almond skins. Immunol. Lett. 132(1-2):18-23.
The elimination of a viral infection requires a proinflammatory host response (type 1 immunity), characterized by activation of mononuclear cells and production of proinflammatory cytokines, such as interferons (IFNs), tumor necrosis factor (TNF)-alpha and interleukin (IL)-12. On the other hand, IL-4 and IL-10 play a role in decreasing the inflammatory response supported by helper T (Th)1 cells. In this study we evaluated the effects of almond skins on the release of cytokines by peripheral blood mononuclear cells (PBMC), either infected or not with herpes simplex virus type 2 (HSV-2). Natural (NS) and blanched almond skins (BS) were subjected to simulated gastric and duodenal digestion and used at not cytotoxic concentrations. NS induced a significant decrease in HSV-2 replication, whereas extracts obtained from BS did not significantly influence the viral replication. High levels of cytokines production, such as IFN-alpha (38±5.3 pg/ml), IL-12 (215±17.1 pg/ml), IFN-gamma (5±0.7 IU/ml), TNF-alpha (3940±201.0 pg/ml), were detected. Moreover, IL-10 (210±12.2 pg/ml) and IL-4 (170±21.4 pg/ml), representative of Th2 responses, were found. Our data suggest that almond skins improve the immune surveillance of PBMC towards viral infection, both by triggering the Th1 and Th2 subsets.
Mandalari, G., A. Tomaino, G.T. Rich, R. Lo Curto, T. Arcoraci, M. Martorana, C. Bisignano, A. Saija, M.L. Parker, K.W. Waldron, M.S.J. Wickham. 2010. Polyphenol and nutrient release from skin of almonds during simulated human digestion. Food Chem. 122:1083-1088.
The bioaccessibility of nutrients and phytochemicals from almond skin has not been previously evaluated. We quantified the release of lipid, protein and polyphenols during simulated human digestion from natural (NS) and blanched (BS) skins, the latter being a by-product of the almond industry. Higher percentages of polyphenols were released from NS compared to BS during in vitro digestion. Most of the limited release of lipid and protein occurred during gastric digestion, with no significant differences between NS and BS. The total dietary fiber content was 45% for NS and 46% for BS, glucose and galacturonic acid being the major sugars present. No changes in dietary fiber composition and distribution of autofluorescent phenolics were observed in the cell walls of almond skin after simulated digestion. In the GI tract, the cell walls may therefore function as a useful source of fermentable fiber with beneficial implications for gut health.
Li, S.-C., Y.-H. Liu, W.-H. Chang, C.-M. Chen, C.-Y. O. Chen, J.-F. Liu. 2010. Almond consumption improved glycemic control and lipid profiles in patients with type 2 diabetes. Metabolism.doi:10.1016/j.metabol.2010.04.009.
Almond consumption is associated with ameliorations in obesity, hyperlipidemia, hypertension, and hyperglycemia. The hypothesis of this 12-week randomized crossover clinical trial was that almond consumption would improve glycemic control and decrease the risk for cardiovascular disease in 20 Chinese patients with type 2 diabetes mellitus (T2DM) (9 male, 11 female; 58 years old; body mass index, 26 kg/m(2)) with mild hyperlipidemia. After a 2-week run-in period, patients were assigned to either a control National Cholesterol Education Program step II diet (control diet) or an almond diet for 4 weeks, with a 2-week washout period between alternative diets. Almonds were added to the control diet to replace 20% of total daily calorie intake. Addition of approximately 60 g almonds per day increased dietary intakes of fiber, magnesium, polyunsaturated fatty acid, monounsaturated fatty acid, and vitamin E. Body fat determined with bioelectrical impedance analysis was significantly lower in patients consuming almonds (almonds vs control: 29.6% vs 30.4%). The almond diet enhanced plasma alpha-tocopherol level by a median 26.8% (95% confidence intervals, 15.1-36.6) compared with control diet. Furthermore, almond intake decreased total cholesterol, low-density lipoprotein cholesterol, and the ratio of low-density lipoprotein cholesterol to high-density lipoprotein cholesterol by 6.0% (1.6-9.4), 11.6% (2.8-19.1), and 9.7% (0.3-20.9), respectively. Plasma apolipoprotein (apo) B levels, apo B/apo A-1 ratio, and nonesterified fatty acid also decreased significantly by 15.6% (5.1-25.4), 17.4% (2.8-19.9), and 5.5% (3.0-14.4), respectively. Compared with subjects in the control diet, those in the almond diet had 4.1% (0.9-12.5), 0.8% (0.4-6.3), and 9.2% (4.4-13.2) lower levels of fasting insulin, fasting glucose, and homeostasis model assessment of insulin resistance index, respectively. Our results suggested that incorporation of almonds into a healthy diet has beneficial effects on adiposity, glycemic control, and the lipid profile, thereby potentially decreasing the risk for cardiovascular disease in patients with type 2 diabetes mellitus.
