Antioxidants and hormone-mediated health benefits of whole grains

Natural antioxidants from some fruits, seeds, foods, natural products, and associated health benefits: An update

Antioxidants are compounds that inhibit the oxidation of other molecules and protect the body from the effects of free radicals, produced either by normal cell metabolism or as an effect of pollution and exposure to other external factors and are responsible for premature aging and play a role in cardiovascular disease. degenerative diseases such as cataracts, Alzheimer's disease, and cancer. While many antioxidants are found in nature, others are obtained in synthetic form and reduce oxidative stress in organisms. This review highlights the pharmacological relevance of antioxidants in fruits, plants, and other natural sources and their beneficial effect on human health through the analysis and in-depth discussion of studies that included phytochemistry and their pharmacological effects. The information obtained for this review was collected from several scientific databases (ScienceDirect, TRIP database, PubMed/Medline, Scopus, Web of Science), professional websites, and traditional medicine books. Current pharmacological studies and evidence have shown that the various natural antioxidants present in some fruits, seeds, foods, and natural products have different health-promoting effects. Adopting functional foods with high antioxidant potential will improve the effective and affordable management of free radical diseases while avoiding the toxicities and unwanted side effects caused by conventional medication.

Assessment of the Impact of the Application of a Quercetin-Copper Complex on the Course of Physiological and Biochemical Processes in Wheat Plants (Triticum aestivum L.) Growing under Saline Conditions

Salt stress is one of the main stressors limiting plant growth and yield. As a result of salt stress, unfavorable changes in the photosynthesis process take place, leading to a decrease in plant productivity. Therefore, it is necessary to use biologically active substances that reduce the effects of this stress. An example of such a substance is quercetin, classified as a flavonoid, which plays an important role in alleviating the effects of salt stress, mainly by the inactivation of reactive oxygen species (ROS) and by improvement of the photosynthesis process. A study was made of the effect of the quercetin–copper complex (Q-Cu (II)), which has a stronger antioxidant effect than pure quercetin. By means of a pot experiment, the influence of solutions of the Q-Cu (II) complex (100 mg∙L⁻¹ [Q1], 500 mg∙L⁻¹ [Q2] and 1000 mg∙L⁻¹ [Q3]) on the physiological and biochemical processes occurring in wheat plants subjected to salt stress was investigated. The plants were given two sprays of Q-Cu (II) solution, and their physiological parameters were examined both 1 and 7 days after each application of this solution. The level of ROS and the activity of antioxidant enzymes (catalase [CAT], superoxide dismutase [SOD] and guaiacol peroxidase [GPOX]) were also determined. It has been shown that spraying with Q2 and Q3 solutions improves the chlorophyll content, the values of chlorophyll fluorescence parameters (the photochemical efficiency of PS II [F_v/F_m], the maximum quantum yield of primary photochemistry [F_v/F₀], and the performance index of PS II [PI]), and gas exchange (net photosynthetic rate [P_n], stomatal conductance [g_s], transpiration rate [E] and intercellular CO₂ concentration [C_i]). As a result of the application of Q2 and Q3 solutions, the level of ROS and the activity of the antioxidant enzymes tested decreased, which means that these concentrations are most effective in counteracting the effects of salt stress.

What is the Modern Human Eating? Dietary Transition of the Age-Old to the Modern Man of India

Objectives: The objective of this review is to examine the changes in food consumption pattern of Indians over the years and to recommend evidence-based policy making regarding all the factors affecting food consumption. Methods: We have reviewed the articles from major databases such as PubMed and Google Scholar. The keywords used for the search included dietary pattern, dietary trend, dietary intake, food system, nutrition system, prehistoric food systems, drought, famine, whole grains, diets, prices, income, environment, urban food consumption, processed foods, food security, food preferences, demographic transition, fat intake, food production, public distribution system, food consumption pattern, Indian agriculture, and India. Results: There is no facilitating environment for the production and cultivation of healthy and sustainable food. Conclusion: Policymakers should make major amendments to food and agricultural policies, and demotivate the consumption of junk food.

Correlation of elongation factor 1A accumulation with photosynthetic pigment content and yield in winter wheat varieties under heat stress conditions

Heat stress is one of the most important environmental factors that influences wheat growth and development, leading to significant losses in grain yield and has become a significant detrimental factor for worldwide wheat production. In recent years, several studies suggested that eukaryotic elongation factor 1A (eEF1A), may contribute to heat tolerance in plants, therefore the aim of this study was: to investigate the accumulation of eEF1A in wheat under conditions of moderate and high air temperatures; to determine the amount of photosynthetic pigments and to determine the yield traits; and to examine whether there is a correlation between eEF1A accumulation, photosynthetic pigments, and yield in different wheat varieties. The results showed that heat stress induced accumulation of eEF1A significantly different among wheat varieties and showed that varieties with a higher accumulation of eEF1A under heat stress are characterized by a smaller decrease in the photosynthetic pigments. A correlation between higher accumulation of eEF1A under heat stress and yield traits was found. Analyzed parameters from two growing seasons, indicated that the higher accumulation of eEF1A and a smaller decrease in photosynthetic pigments distinguishes the varieties more resistant to heat stress. The analysis of the molecular mechanisms by immunoblot, under conditions of high and moderate air temperatures in two growing seasons, aims to develop agricultural strategy and develop wheat varieties tolerant to heat stress.

Cereal grain-based functional beverages: from cereal grain bioactive phytochemicals to beverage processing technologies, health benefits and product features

Increased consumer awareness of health and wellness has promoted a high demand for foods and beverages with functional and therapeutic properties. Cereals, apart from being important staple crops and primary sources of energy and nutrition, are replete with bioactive phytochemicals with health properties. Cereal grains contain a diverse range of bioactive phytochemicals including phenolic compounds, dietary fibers, carotenoids, tocols, phytosterols, γ-oryzanol, and phytic acid and therefore have great potential for processing into functional beverages. Although there are a variety of cereal grain-based beverages produced world-wide, very little scientific and technological attention has been paid to them. In this review, we have discussed cereal grain-based functional beverages based on 3 main categories: cereal grain-based milk alternatives, roasted cereal grain teas, fermented nonalcoholic cereal grain beverages. The processing techniques, health properties and product features of these beverages are elaborated, and the challenges and future perspectives are proposed. As the food market becomes increasingly diverse, cereal grain-based beverages could be a promising new category of health functional beverages in our daily life.

Chapatti sensory and textural quality in relation to whole meal flour and dough characteristics

Current study was designed to evaluate sensory and textural quality characteristics of chapatti, a commonly consumed flat bread in South-Asia in relation to flour quality parameters. Whole meals of cultivars and commercial wheat samples were analysed for physicochemical, pasting, dough and baking properties. Flours contained medium protein contents (12.4-13.7%) and possessed medium to high gluten strength (51-88). Pasting and dough properties were also suitable for chapatti making. Chapatti sensory attributes were strongly related to gluten content (r = -0.915) and strength (r = 0.851). Moderate relationships were also observed with protein (r = -0.665), falling number (r = -0.750), water absorption (r = -0.623) and maximum viscosity (r = -0.745) of whole meal flours. Tearing force for chapatti was largely related to gluten content (r = -0.893) and dough development time (r = 0.847) but also showed reasonable relationships with gluten index (r = 0.643), ash (r = 0.640), falling number (r = -0.681), maximum (r = -0.743) and breakdown (r = -0.650) viscosities. The information would be useful for household and commercial semi-mechanical chapatti-making process.

Modeling and optimizing microwave-assisted extraction of antioxidants from Thymbra Spicata L. and characterization of their phenolic constituents

Response surface methodology was used for modeling and optimizing microwave-assisted extraction of antioxidants from Thymbra spicata L. as a factor of temperature, extraction time, solvent concentration, and solvent-to-solid ratio. The prepared extracts showed maximum antioxidant properties, including total phenolic content (TPC), total antioxidant capacity (TAC), and radical scavenging activity (RSA) at the optimum operating conditions. All models calculated for the three responses that are TPC, TAC, and RSA were noteworthy (p < 0.0001) and showed a significant relationship between the response and independent parameters. There was a close relationship between the experimental and the predicted values obtained using the proposed method. The phenolic antioxidant profile of Thymbra spicata L. extract was characterized with the UPLC-PDA-ESI-MS/MS system and rosmarinic acid was found as a major component (1089.2 ± 10.9 mg/100 g-DS). In the future, this optimized and modeled MAE method can be applied in food and pharmaceutical industries to effectively extract antioxidants from edible Thymbra spicata L. plant.

Determination of phenolic compounds in ancient and modern durum wheat genotypes

Due to its significant amount of antioxidants, durum wheat (Triticum turgidum ssp. durum) could potentially contribute to the protection against a number of chronic diseases, such as diabetes, cardiovascular disease, and cancer. The increasing interest toward healthy food among both consumers and scientists has moved the focus toward the phytochemical content of whole wheat grains. The aim of this study was to identify the phytochemical composition of 22 cultivars belonging to old and modern durum wheat genotypes, including antioxidant capacity (DPPH and FRAP tests). In addition, five phenolic acids involved in the vanillin biosynthesis pathway and in the defence mechanism of plants were screened using UHPLC-MS/MS. Remarkable quantitative differences in the amount of the five phenolic acids analysed (p < 0.05) were detected among the wheat genotypes investigated. Results showed that among the investigated phenolic compounds, trans-ferulic acid was the most abundant, ranging from 13.28 to 324.69 μg/g; all the other identified compounds were present at lower concentrations. Moreover, significant differences on the antioxidant activity were observed. Collected data suggested possible differences between biosynthetic pathway of secondary metabolites among durum wheat genotypes.

Availability and dose response of phytophenols from a wheat bran rich cereal product in healthy human volunteers

SCOPE

Phytophenols present in cereals are metabolised to compounds that could be partly responsible for the reduced risk of chronic diseases and all-cause mortality associated with fibre-rich diets. The bioavailability, form and in vivo concentrations of these metabolites require to be established.

MATERIALS AND METHODS

Eight healthy volunteers consumed a test meal containing a recommended dose (40 g) and high dose (120 g) of ready-to-eat wheat bran cereal and the systemic and colonic metabolites determined quantitatively by LC-MS.

CONCLUSION

Analysis of the systemic metabolomes demonstrated that a wide range of phytophenols were absorbed/excreted (43 metabolites) within 5 h of consumption. These included 16 of the 21 major parent compounds identified in the intervention product and several of these were also found to be significantly increased in the colon. Not all of the metabolites were increased with the higher dose, suggesting some limitation in absorption due to intrinsic factors and/or the food matrix. Many compounds identified (e.g. ferulic acid and major metabolites) exhibit anti-inflammatory activity and impact on redox pathways. The combination of postprandial absorption and delivery to the colon, as well as hepatic recycling of the metabolites at these concentrations, is likely to be beneficial to both systemic and gut health.

Whole Grains in Amelioration of Metabolic Derangements

Daily diet influences whole body metabolism, and intricately linked to the prevention or progression of metabolic diseases including obesity, diabetes and cardiovascular diseases. Several epidemiological and large scale studies have shown that diets enriched with whole grains improves metabolic function and protect from the development of metabolic diseases. Direct impact of whole grain diet can be mediated on several levels of metabolic functions i.e. reduced glycemic index, improved fat oxidation potential, increased cholesterol clearance or decreased cholesterol biosynthesis and modulation of gut microbiome. In this article we reviewed several studies indicating the beneficial effects of whole grain diets on metabolic functions, as well as discussed the potential active phytochemicals present in these whole grain foods to contribute in modulation of metabolic function in our body.

Note. β—Carotene, α—tocopherol and γ—tocopherol contents in dry legumes. Influence of cooking Nota. Contenido de β—caroteno, α—tocopherol y γ—tocopherol en legumbres secas. Influencia de la cocción

Three essential fat-soluble micronutrients—β-carotene, α-tocopherol and γ-tocopherol-were de termined by HPLC in different varieties of three dry legumes, namely, beans, chick peas and lentils. Their distribution between skin and albumen was also determined. After cooking legumes were found significantly to preserve most of these micronutrients.

Whole Grain Intake Reduces Pancreatic Cancer Risk: A Meta-Analysis of Observational Studies

Mounting evidence from epidemiology studies suggests that whole grain intake may reduce pancreatic cancer risk, but convincing evidence is scarce. We conducted a meta-analysis to assess the association between whole grain intake and pancreatic cancer risk. Relevant observational studies were identified by searching PubMed, Embase, Scopus, and Cochrane library databases for the period from January 1980 to July 2015, with no restrictions. We calculated the summary odds ratios (ORs) for pancreatic cancer using random-effects model meta-analysis. Between-study heterogeneity was analyzed using the I statistic. A total of 8 studies regarding whole grain intake were included in the meta-analysis. The pooled OR of pancreatic cancer for those with high versus low whole grain intake was 0.76 (95% confidence interval [CI], 0.64-0.91; P = 0.002). There was no significant heterogeneity across these studies (I² = 11.7%; Pheterogeneity = 0.339). In the subgroup analysis by geographic area, the summary ORs of developing pancreatic cancer were 0.64 (95% CI, 0.53-0.79; P < 0.001; I ²= 0%; Pheterogeneity = 0.482) in the United States (n = 4) and 0.95 (95% CI, 0.63-1.43; P = 0.803; I ²= 45.6%; Pheterogeneity = 0.175) in Europe (n = 2). In the subgroup analysis by type of whole grain, the summary ORs were 0.72 (95% CI, 0.60-0.87; P = .001; I² = 0; Pheterogeneity = 0.876) for grains (n = 4) and 0.74 (95% CI, 0.27-2.02; P = 0.554; I² = 86.3%; Pheterogeneity = 0.007) for wheat (n = 2). A high intake of whole grains was associated with a reduced risk of pancreatic cancer. Because of the absent of more cohort studies, further prospective studies need to be conducted to ensure conclusions that are more robust.

Antioxidant properties of diverse cereal grains: A review on in vitro and in vivo studies

Cereal grains and products have gained popularity in contributing to healthy eating behavior because of their antioxidant properties associated with protection against chronic diseases. In this review, notable studies on the in vitro and in vivo antioxidant activity of commonly consumed cereal grains are summarized. Cereals contain phytochemicals or certain minor components with antioxidant properties. The antioxidant potential of cereals depends on their bioaccessibility, absorption in the gastrointestinal and their bioavailability utilization in vivo. The in vitro gastrointestinal digestion and fermentation of cereals increased their antioxidant potentials which are significantly correlated with their total phenolic contents. Most studies performed in vivo have been concerned with the antioxidant properties of colored rice, wheat bran and rye products. There are inadequate in vitro and in vivo studies on antioxidative potentials of fermented versus unfermented cereals. Therefore, further studies are necessary to maximize possible health benefits of cereal antioxidative phytochemicals.

The impact of milling and thermal processing on phenolic compounds in cereal grains

Consumption of wholegrain foods has been recommended for healthy diets. The beneficial health properties of wholegrain products have been associated with the presence of higher amounts of dietary fiber and antioxidants and lower calories as compared to their respective refined ones. Phenolic compounds are mainly attributed to antioxidant properties of wholegrain foods. This review article provides a single comprehensive source that describes effects of milling and thermal processing on phenolic compounds and antioxidant properties in cereals. In general, milling and pearling processes affect the distribution of phenolic, compounds and thus antioxidant properties vary among the milling fractions. Thermal processes such as baking and extrusion could cause negative or positive effects on phenolic compounds and antioxidant properties of the end product subject to grain type and processing conditions. Thus factors that enhance health benefits of wholegrain cereal products have been discussed.

Significance of coarse cereals in health and nutrition: a review

This review assesses the nutritional attributes of coarse cereals and also their utilization as food and as formulated foods. These cereals are laden with phytochemicals including phenolic acids, tannins, anthocyanins, phytosterols, avenenathramides and policosanols. They possess high antioxidant properties in vitro than staple cereals and fruits by different purported pathways. There are also some anti-nutritional factors that may be reduced by certain processing treatments. Several epidemiological studies show that these cereals are helpful in reducing several kinds of chronic diseases like cancers, cardiovascular diseases, type II diabetes and various gastrointestinal disorders. Being coarse in nature, they cannot replace our staple cereals, but can be used in different proportions with rice and wheat to formulate various nutritional products. They can be used to make porridges, biscuits, cakes, cookies, tortillas, bread, probiotic drinks, ladoo, ghatta, flakes and several fermented foods. The coarse cereals also have good potential in manufacturing bioethanol, paper, oil and biofilms.

Health-promoting phytochemicals of Italian common wheat varieties grown under low-input agricultural management

BACKGROUND

The increasing interest in organic food products and environmental friendly practices has emphasised the importance of selecting crop varieties suitable for the low-input sector. Moreover, in recent years the relationship between diet and human health has gained much attention among consumers. The aim of this study was to comparatively evaluate the agronomic performance and the nutrient and phytochemical composition of old and modern Italian wheat genotypes grown under low-input management.

RESULTS

Research highlighted that several old wheat genotypes were comparable to the modern ones in terms of agronomic performance and nutrient content. Genotype and environmental conditions (growing season), as well as their interaction, significantly affected the phytochemical composition of wheat grains for most of the analysed bioactive compounds. High variability was observed among the wheat genotypes for dietary fibre (154.7-183.3 g kg⁻¹), polyphenol (1.94-2.77 mg g⁻¹), tocopherol (9.1-21.2 mg kg⁻¹) and carotenoid (701.4-3243 µg kg⁻¹) content.

CONCLUSION

The comparative study of old and modern wheat varieties highlighted that, under low-input conditions, ancient genotypes may equal modern ones in terms of agronomic traits and additionally provide nutraceutical value-added wheat grains. The most promising ancient varieties for the unique phytochemical profiles are Gentil rosso, Marzuolo d'aqui and Verna.

Prebiotic effect of soluble fibres from modern and old durum-type wheat varieties on Lactobacillus and Bifidobacterium strains

BACKGROUND

Wheat grains are a rich source of dietary fibres, particularly in the western human diet. Many of the health effects attributed to dietary fibres are believed to be related to their microbial fermentation in the gut. This study evaluated the ability of two potentially probiotic strains, Lactobacillus plantarum L12 and Bifidobacterium pseudocatenulatum B7003, to ferment soluble dietary fibres (SDFs) from modern and ancient durum-type wheat grains.

RESULTS

Fibre microbial utilisation was highly variable and dependent on the strain. SDFs from the varieties Svevo and Solex supported the growth of L. plantarum L12 the best, whereas those from the varieties Anco Marzio, Solex and Kamut(®) Khorasan were good carbohydrate substrates for B. pseudocatenulatum B7003. The highest prebiotic activity scores (describing the extent to which prebiotics support selective growth of probiotics) for B7003 were obtained with SDFs from the varieties Solex (0.57), Kamut(®) Khorasan (0.56) and Iride (0.55), whereas for L12 the highest scores were achieved with the varieties Orobel (0.63), Kamut(®) Khorasan (0.56) and Solex (0.53).

CONCLUSION

The present study has identified some SDFs from durum-type wheat grains as suitable prebiotic substrates for the selective proliferation of B. pseudocatenulatum B7003 and L. plantarum L12 in vitro. The results provide the basis for the potential utilisation of wheat-based prebiotics as a component of synbiotic formulations.

Diet for the prevention of asthma and allergies in early childhood: much ado about something?

In the last decades there has been an increase in allergic disease throughout the world, particularly in children. Attempts have been made to identify the causes of this "allergy epidemic" in environmental changes and changes in population hygiene, lifestyle, socioeconomic level, and eating habits that would exert epigenetic effects. Dietetic hypotheses have been mainly focussed in long-chain polyunsaturated fatty acids, vitamin D, antioxidants, Mediterranean diet, and fruits, vegetables and fish consumption. Although the data suggest a certain association between diet and the development of asthma/allergy, there is no evidence that diet has an impact upon the prevalence of such diseases after early infancy. If indeed there is such an impact, it is likely to be confined to the prenatal period and the first months of life - when it is still possible to modulate the development of the respiratory, digestive and immune systems. Thus, once the most appropriate preventive measures have been defined, these should be implemented during pregnancy and lactation. The existing scientific evidence is unable to recommend any primary preventive measure in the general population or in different population subgroups. Special or restrictive diets in pregnant or nursing women are not indicated. Exclusive breastfeeding for six months is questioned, since solid foods should begin to be introduced at around four months of age. Once the atopic process has started, no nutritional strategies have been found to be effective as secondary or tertiary preventive measures. Longitudinal studies in cohorts of pregnant women or newborn infants could help clarify these issues.

Profiles of phenolic compounds in modern and old common wheat varieties determined by liquid chromatography coupled with time-of-flight mass spectrometry

The health-promoting properties of common wheat (Triticum aestivum L.) have been largely attributed to the presence of unique phytochemicals of whole grains. The aim of this study was to profile the phenolic content of 16 old and 6 modern Italian wheat varieties, cropped in the same location and growing season. High variability was observed among the investigated wheat genotypes, both in the free and bound phenolic extracts. The total polyphenol content ranged from 885.5 to 1715.9 μmol GAE/100 g of grain and, on average, the bound fraction contributed for 72.0% to the total phenolic content. As regards the flavonoid content, the free fraction ranged from 50.7 to 106.1 μmol CE/100 g of grain and the bound fraction from 78.3 to 148.9 μmol CE/100 g of grain. Moreover, the interpretation of the mass spectra allowed the characterization of 34 phenolic compounds (104 including isomer forms) belonging to the phenolic acid, flavonoid, coumarin, stilbene, proanthocyanidin and lignan chemical classes. HPLC-ESI-TOF-MS analysis highlighted remarkable differences in the phytochemical fingerprints of old and modern wheat varieties. Six ancient wheat genotypes (Bianco Nostrale, Frassineto, Gentil Rosso, Gentil Rosso Mutico, Marzuolo d'Aqui, Verna) showed phenolic profiles with a number of total compounds and isomer forms much higher than that identified in the modern cultivars. The present findings confirm that ancient wheat may represent a valuable source of biodiversity, especially as regards phenolic compounds. The investigated old wheat genotypes may be successfully used in breeding programs for developing bread wheat varieties with added value in terms of health-promoting phytochemicals.

Effects of environment and genotype on phenolic acids in wheat in the HEALTHGRAIN diversity screen

Phenolic acid content and composition have been determined in 26 wheat genotypes grown in Hungary over three consecutive years and at three additional locations (France, United Kingdom, and Poland) during the third year. Fractions comprising free, soluble conjugated, and bound phenolic acids were analyzed using HPLC with measurements being made for individual phenolic acids in each fraction. Statistically significant differences in phenolic acid content occurred across the different growing locations with the average total phenolic acid content being highest in the genotypes grown in Hungary. The growth year in Hungary also had a large impact, especially on the free and conjugated phenolic acid contents. Certain genotypes were more resistant to environmental impacts than others. Of the genotypes with high levels of total phenolic acids, Lynx, Riband, Tommi, and Cadenza were most stable with respect to their total contents, whereas Valoris, Herzog, and Malacca, also high in phenolic acid content, were least stable. Of the three fractions analyzed, the free and conjugated phenolic acids were most variable and were also susceptible to the effect of environment, whereas bound phenolic acids, which comprised the greatest proportion of the total phenolic acids, were the most stable.

Determination of phenolic compounds in modern and old varieties of durum wheat using liquid chromatography coupled with time-of-flight mass spectrometry

An evaluation of the grain functional components of Italian durum wheat cultivars was conducted. The raw material was obtained from the field trial performed in 2006-2007 at the Experimental Farm of the University of Bologna, (Bologna, Italy). The aim of this study was to define the phytochemical profile of ten varieties, comprised of old and modern durum wheat genotypes, including quantitative and qualitative phenolic and flavonoid content (free and bound forms). The results showed that mean values of total phenolic compound and total flavonoid content in old wheat varieties (878.2+/-19.0 micromol gallic acid equivalent/100g of grain and 122.6+/-25.4 micromol catechin equivalent/100g of grain, respectively) did not differ significantly from those detected in modern genotypes (865.9+/-128.9 micromol gallic acid equivalent/100g and 123.5+/-20.6 micromol catechin equivalent/100g, respectively). However, the HPLC-ESI-TOF-MS analysis highlighted remarkable differences between modern and old cultivars. The interpretation of the mass spectra allowed the identification of 70 phenolic compounds, including coumarins, phenolic acids, anthocyanins, flavones, isoflavones, proanthocyanidins, stilbenes and lignans. The free extracts of ancient wheat varieties showed the presence of a mean number of phenolic compounds and isomer forms (8.7+/-2.5 and 7.7+/-4.7 respectively) significantly higher than in modern genotypes (4.4+/-2.9 and 2.0+/-2.4, respectively). A similar trend was observed also for the bound phenolic fraction. Moreover, the phytochemical profiles showed the presence of unique phenolic compounds in both free and bound fractions of some of the investigated wheat genotypes. Results highlighted that investigated old wheat cultivars may offer unique nutraceutical values for their peculiar contents in bioactive phytochemicals, suggesting their uses into a wide range of regular and specialty products naturally enriched with health-promoting compounds.

Maize authentication: quality control methods and multivariate analysis (chemometrics)

Maize is one of the most important cereals because of its numerous applications in processed foods where it is the major or minor component. Apart from maize authenticity issues related to cultivar and geographical origin (national and/or international level), there is another important issue related to genetically modified maize. Various objective parameters such as fatty acids, phenolic compounds, pigments, heavy metals were determined in conjunction with subjective (sensory analysis) in order to identify the maize authenticity. However, the implementation of multivariate analysis (principal component analysis, cluster analysis, discriminant analysis, canonical analysis) is of great importance toward reaching valid conclusions on authenticity issues. This review summarized the most important finding of both objective and subjective evaluations of maize in five comprehensive tables in conjunction with the discussion.

Phenolic acids in wheat varieties in the HEALTHGRAIN Diversity Screen

The amounts and compositions of free, conjugated, bound, and total phenolic acids were determined in 175 samples of wheat flour grown on a single site in 2005. The highest contents of total phenolic acids were found in flours of winter wheat (1171 microg/g) with average levels of 658 microg/g total phenolics across all of the wheat genotypes. Winter wheats showed a range of >3.5-fold across the concentration range for total phenolic acids. Spelt genotypes displayed the narrowest (1.9-fold) range of total phenolic acid concentration. The concentrations of phenolic acids in the different phenolic acid fractions were in the order bound > conjugated > free, with bound phenolic acids making up around 77% of the total phenolic acid concentration and free phenolic acids constituting between 0.5 and 1%. The results indicate that there is genetic diversity in phenolic acid content and that it should be possible to selectively breed for lines with high contents of phenolic components.

Effects of laccase and xylanase on the chemical and rheological properties of oat and wheat doughs

The effects of Trametes hirsuta laccase and Pentopan Mono BG xylanase and their combination on oat, wheat, and mixed oat-wheat doughs and the corresponding breads were investigated. Laccase treatment decreased the content of water-extractable arabinoxylan (WEAX) in oat dough due to oxidative cross-linking of feruloylated arabinoxylans. Laccase treatment also increased the proportion of water-soluble polysaccharides (WSNSP) apparently due to the beta-glucanase side activity present in the laccase preparation. As a result of the laccase treatment, the firmness of fresh oat bread was increased. Xylanase treatment doubled the content of WEAX in oat dough and slightly increased the amount of WSNSP. Increased stiffness of the dough and firmness of the fresh bread were detected, probably because of the increased WEAX content, which decreased the amount of water available for beta-glucan. The combination of laccase and xylanase produced slight hydrolysis of beta-glucan by the beta-glucanase side activity of laccase and enhanced the availability of AX for xylanase with concomitant reduction of the amount and molar mass of WSNSP. Subsequently, the volume of oat bread was increased. Laccase treatment tightened wheat dough, probably due to cross-linking of WEAX to higher molecular weight. In oat-wheat dough, laccase slightly increased the proportion of WSNSP between medium to low molecular weight and increased the specific volume of the bread. Xylanase increased the contents of WEAX and WSNSP between medium to low molecular weight in oat-wheat dough, which increased the softness of the dough, as well as the specific volume and softness of the bread. The results thus indicate that a combination of laccase and xylanase was beneficial for the textures of both oat and oat-wheat breads.

The key importance of soy isoflavone bioavailability to understanding health benefits

Research over the past two decades has provided significant epidemiological and other evidence for the health benefits of the consumption of soy-based foods. A large number of dietary intervention studies have examined the effects of soy isoflavones on risk factors for cardiovascular disease and hormone-dependent cancers. However, these report large variability in outcome measures, very limited reproducibility between studies, and in some cases, controversy between the results of clinical trials using dietary soy or soy protein and isoflavone supplementation. This highlights a major gap in our understanding of soy isoflavone uptake, metabolism, distribution, and overall bioavailability. There are many potential factors that may influence bioavailability and a better knowledge is necessary to rationalize the inconsistencies in the intervention and clinical studies. This review focuses attention on our current state of knowledge in this area and highlights the importance of metabolism of the parent soy isoflavones and the critical role of gut microbiota on the bioavailability of these compounds and their metabolites.

Oat: unique among the cereals

This review is intended to focus on the composition of oat and its therapeutic potential in the pharmacology that supports its use to cure various maladies. Oat (Avena sativa) is distinct among the cereals due to its multifunctional characteristics and nutritional profile. Recent advancement in food and nutrition has revealed the importance of its various components. It is a good source of dietary fiber especially beta-glucan, minerals and other nutrients. Oat and oat by products have been proven to be helpful in the treatment of diabetes and cardiovascular disorders. Oat bran in particular, is good source of B complex vitamins, protein, fat, minerals besides heart healthy soluble fiber beta-glucan. The beta-glucan has outstanding functional properties and is of immense importance in human nutrition. Different physiological effects of beta-glucan are related to its viscosity, attenuation of postprandial plasma glucose and insulin responses, high transport of bile acids towards lower parts of the intestinal tract and high excretion of bile acids thereby lowering of serum cholesterol levels. Moreover, it is helpful against coeliac disease. The incorporation of oat grains and oat bran in the food products improves not only the nutrition but also a therapy against various maladies.

Intake of whole grains, refined grains, and cereal fiber measured with 7-d diet records and associations with risk factors for chronic disease

BACKGROUND

Research studies examining foods are important, because they account for biological interactions that might otherwise be lost in the analysis of individual nutrients. Single-nutrient studies are also needed to explore the mechanisms by which foods may be protective.

OBJECTIVE

Our objective was to examine associations between whole grains, refined grains, and cereal fiber and chronic disease risk factors.

DESIGN

In a cross-sectional analysis of participants in the Baltimore Longitudinal Study of Aging, associations between dietary intakes and risk factors were examined with multivariate linear regression analysis. Dietary intakes were assessed with 7-d dietary records and quantified in g/d.

RESULTS

Compared with subjects in the lowest quintile (Q1) of whole-grain intake, subjects in the highest quintile (Q5) had lower body mass index (BMI; in kg/m(2); Q1: 25.5; Q5: 24.8; P for trend <0.0001) and weight (Q1: 75.0 kg; Q5: 72.4 kg; P for trend = 0.004) and smaller waist circumference (Q1: 87.4 cm; Q5: 85.0 cm; P for trend = 0.002). Whole grains were also inversely associated with total cholesterol (P for trend = 0.02), LDL cholesterol (P for trend = 0.04), and 2-h glucose (P for trend = 0.0006). Associations between cereal fiber and anthropometrics and plasma lipids were similar. In subgroup analyses, refined grains were positively associated with fasting insulin among women (P for trend = 0.002).

CONCLUSIONS

Similar associations of whole grains and cereal fiber with weight, BMI, waist circumference, plasma cholesterol, and 2-h glucose were observed, suggesting that cereal fiber and its constituents may in part mediate these relations. Refined grains were associated with fasting insulin among women but not men. Additional research should explore potential interaction effects with BMI, sex, age, and genes.

Hypoglycemic effects of a phenolic acid fraction of rice bran and ferulic acid in C57BL/KsJ-db/db mice

Rice bran contains many phenolic acids, the most abundant of which is the antioxidant, ferulic acid (FA). We evaluated the hypoglycemic effects of a phenolic acid fraction (the ethyl acetate fraction, EAE) of rice bran and of FA in C57BL/KsJ db/db mice. Type 2 diabetic mice were allocated to a control group, an EAE group, or an FA group. Animals were fed a modified AIN-76 diet, and EAE or FA was administered orally for 17 days. There was no significant difference in body weight gain between groups. Administration of EAE and FA significantly decreased blood glucose levels and increased plasma insulin levels. EAE or FA groups had significantly elevated hepatic glycogen synthesis and glucokinase activity compared with the control group. Plasma total cholesterol and low density lipoprotein (LDL) cholesterol concentrations were significantly decreased by EAE and FA administration. These findings suggest that EAE and FA may be beneficial for treatment of type 2 diabetes because they regulate blood glucose levels by elevating glucokinase activity and production of glycogen in the liver.

Phytoestrogens: perpetrators or protectors?

Phytoestrogens are estrogen-like substances produced by plants that account for some of the constituents present in vegetation that may be responsible for the health benefits of a diet rich in fruit and vegetables. Phytoestrogens have a plethora of different actions that they are capable of exerting on cellular metabolism. This review will focus on some of the major non-estrogen receptor-mediated cellular effects used by phytoestrogens and will draw attention to the fact that while they may have a number of beneficial effects, particularly in offering a protective effect against some hormone-dependent cancers, such as breast and prostate cancer, they may also have possible unfavorable effects by interfering with the functioning of normal cellular activities such as receptor-mediated signal transduction and DNA replication, as well as being genotoxic, mutagenic and promoting the proliferation of some cancer cells.

Relationship between phenolic compounds, anthocyanins content and antioxidant activity in colored barley germplasm

Barley and its products are good sources of antioxidants. This experiment was conducted to examine the classification and concentration of phenolic compounds, proanthocyanidins, and anthocyanins in 127 lines of colored barley. Their relationship with 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity was also examined. Barley was placed into seven groups using the colorimeter: hulled (black 1, black 2, black 3, and purple) and unhulled (black, blue, and purple). The contents of phenolic compounds and anthocyanins were analyzed by using HPLC. The average content of phenolic compounds in unhulled barley groups (268.6 microg/g) was higher than that in hulled (207.0 microg/g) (P > 0.05). The proanthocyanidins content was determined by modified vanillin assay. The average content of proanthocyanidins was significantly higher in purple and blue barley groups compared with black (P < 0.05). The content of anthocyanins varied from 13.0 to 1037.8 microg/g. Purple and blue barley groups contained higher average contents of anthocyanins than black (P < 0.05). The most common anthocyanin in the purple barley groups was cyanidin 3-glucoside, whereas delphinidin 3-glucoside was the most abundant anthocyanin in the blue and black groups. In colored barley, DPPH radical scavenging activity had high positive correlation to the content of phenolic compounds and proanthocyanidins.

Whole-grain and refined wheat flours show distinct metabolic profiles in rats as assessed by a 1H NMR-based metabonomic approach

The protection against diabetes and cardiovascular disease provided by whole-grain cereal consumption has been attributed to the fiber and micronutrients present in the bran. But exactly how this occurs remains unclear due to both diversity of bran constituents and the complexity of the metabolic responses to each of these constituents. We investigated the metabolic responses of 2 groups of rats (n = 10/group) fed 2 diets, for 2 wk each, in a crossover design. One diet contained 60 g/100 g whole-grain wheat flour (WGF) and the other contained 60 g/100 g refined wheat flour (RF). Markers of oxidative stress [urinary isoprostanes and malondialdehydes (MDA), plasma ferric-reducing ability of plasma, MDA, and vitamins E and C] and lipid status (liver and plasma triglycerides and cholesterol) were measured. Urine samples collected during the feeding periods and plasma and liver samples collected at the end of experiment were analyzed by (1)H NMR spectroscopy. Metabonomic analyses showed that each group reached a new metabolic balance within 48 h of changing the diet. Urinary excretion of some tricarboxylic acid cycle intermediates, aromatic amino acids, and hippurate was significantly greater in rats fed the WGF diet. Although the diets did not affect conventional lipid and oxidative stress markers, there were decreases in some liver lipids and increases in liver reduced glutathione and betaine as shown by metabonomic analyses. These suggest that the WGF diet improved the redox and lipid status.

Behavioural, attitudinal and dietary responses to the consumption of wholegrain foods

Whole grains are important dietary constituents as they provide a plethora of nutrients and protective chemicals that may have synergistic actions in promoting health. Regular consumption of wholegrain foods has been associated with a reduced risk of several chronic diseases such as CHD and certain cancers, although their exact role in disease prevention is not yet fully elucidated. Studies reporting levels of whole grain consumption reveal that those subjects who include higher levels of whole grain foods in their diets also have many other favourable dietary and lifestyle practices. While the actions of these practices and whole grains may not be mutually exclusive, these variables do not appear to explain the reduction in risk of disease observed for high-whole grain consumers. Actual whole grain consumption levels are extremely low and many practical barriers exist to consumer uptake of these foods. Effective communication of the whole grain health message is an important strategy to increase awareness of the importance of whole grains in the diet. Increasing the variety and availability of acceptable wholegrain foods is also important. Whole grain consumption at breakfast can have an important impact on total daily nutrient intakes. This simple dietary modification is potentially relatively easy to achieve and could greatly contribute to increased whole grain intake for many individuals.