Variability in phytic acid content and protein digestibility of grain legumes

A Review of the Treatments to Reduce Anti-Nutritional Factors and Fluidized Bed Drying of Pulses

Pulses, rich in proteins, dietary fibers, and essential nutrients, play an important role in human nutrition, especially as alternatives to animal proteins. However, the presence of anti-nutritional factors (ANFs), such as trypsin inhibitors, chymotrypsin inhibitors, phytic acid, and tannins, can hinder nutrient absorption, reduce protein digestibility, and impair the overall nutritional value of these foods (pulses). This literature review critically examines fluidized bed drying (FBD) as a promising method for processing pulses, with a focus on the effectiveness of FBD in reducing ANFs while preserving protein quality. The review highlights the impact of FBD on the quality and nutritional properties of pulses, discussing the effect of FBD on different kind of ANFs. Although FBD shows significant potential in reducing certain enzyme inhibitors, it has limitations in removing thermally stable ANFs, such as phytic acid. Furthermore, the review explores energy and exergy efficiencies in FBD systems, emphasizing the need for advanced technologies such as air recycle systems to enhance sustainability. This review identifies significant gaps in existing research, particularly in optimizing FBD methods for the effective removal of ANFs and in developing energy-efficient processing strategies.

Nutritional composition, health benefits and bio-active compounds of chickpea (Cicer arietinum L.)

Chickpea (Cicer arietinum L.), an annual plant of the family Fabaceae is mainly grown in semiarid and temperate regions. Among pulses, cultivated worldwide chickpeas are considered an inexpensive and rich source of protein. Chickpea is a good source of protein and carbohydrate, fiber, and important source of essential minerals and vitamins. The quality of protein is better among other pulses. Consumption of chickpeas is related to beneficial health outcomes. Dietary peptides from the protein of chickpeas gaining more attention. Peptides can be obtained through acid, alkali, and enzymatic hydrolysis. Among all these, enzymatic hydrolysis is considered safe. Various enzymes are used for the production of peptides, i.e., flavorzyme, chymotrypsin, pepsin, alcalase, papain, and trypsin either alone or in combinations. Chickpea hydrolysate and peptides have various bioactivity including angiotensin 1-converting enzyme inhibition, digestive diseases, hypocholesterolemic, CVD, antioxidant activity, type 2 diabetes, anti-inflammatory, antimicrobial, and anticarcinogenic activity. This review summarizes the nutritional composition and bioactivity of hydrolysate and peptides obtained from chickpea protein. The literature shows that chickpea peptides and hydrolysate have various functional activities. But due to the limited research and technology, the sequences of peptides are unknown, due to which it is difficult to conduct the mechanism studies that how these peptides interact. Therefore, emphasis must be given to the optimization of the production of chickpea bioactive peptides, in vivo studies of chickpea bioactivity, and conducting human study trials to check the bioactivity of these peptides and hydrolysate.

Ideotype breeding for crop adaptation to low phosphorus availability on extensive organic farms

Organic farming in extensive production regions, such as the Canadian prairies have a particularly difficult challenge of replenishing soil reserves of phosphorus (P). Organic grains are exported off the farm while resupply of lost P is difficult due to limited availability of animal manures and low solubility of rock organic fertilizers. As a result, many organic farms on the prairies are deficient in plant-available P, leading to productivity breakdown. A portion of the solution may involve crop genetic improvement. A hypothetical 'catch and release' wheat ideotype for organic production systems is proposed to (i) enhance P uptake and use efficiency but (ii) translocate less P from the vegetative biomass into the grain. Root traits that would improve P uptake efficiency from less-available P pools under organic production are explored. The need to understand and classify 'phosphorus use efficiency' using appropriate indices for organic production is considered, as well as the appropriate efficiency indices for use if genetically selecting for the proposed ideotype. The implications for low seed P and high vegetative P are considered from a crop physiology, environmental, and human nutrition standpoint; considerations that are imperative for future feasibility of the ideotype.

Assessment of the risks of copper- and zinc oxide-based nanoparticles used in Vigna radiata L. culture on food quality, human nutrition and health

The present article aims to assess the phytotoxic effects of copper and zinc oxide nanoparticles (Cu NPs, ZnO NPs) on mung bean (Vigna radiata L.) and their possible risk on food quality and safety. We also study the molecular mechanisms underlying the toxicity of nanosized Cu and ZnO. Seeds of mung bean were germinated under increasing concentrations of Cu NPs and ZnO NPs (10, 100, 1000, 2000 mg/L). We analyzed levels of free amino acids, total soluble sugars, minerals, polyphenols and antioxidant capacity. Our results showed that depending on the concentrations used of Cu NPs and ZnO NPs, the physiology of seed germination and embryo growth were modified. Both free metal ions and nanoparticles themselves may impact plant cellular and physiological processes. At 10 mg/L, an improvement of the nutritive properties, in terms of content in free amino acids, total soluble sugars, essential minerals, antioxidant polyphenols and flavonoids, was shown. However, higher concentrations (100-2000 mg/L) caused an alteration in the nutritional balance, which was revealed by the decrease in contents and quality of phenolic compounds, macronutrients (Na, Mg, Ca) and micronutrients (Cu, Fe, Mn, Zn, K). The overall effects of Cu and ZnO nanoparticles seem to interfere with the bioavailability of mineral and organic nutrients and alter the beneficial properties of the antioxidant phytochemicals, mineral compounds, phenolic acids and flavonoids. This may result in a potential hazard to human food and health, at some critical doses of nanofertilizers. This study may contribute in the guidelines to the safe use of nanofertilizers or nanosafety, for more health benefit and less potential risks.

Impacts and Industrial Applications of Phytic Acid and Phytase

Phytic acid is an antinutritional compound that chelates P and essential divalent cations such as Fe, Ca, and Zn in cereals and major staple crops such as wheat, maize, rice, and sorghum. As a result, these cations cannot be absorbed by monogastric animals or humans: phytic acid has an inhibitory effect on nutrient uptake and its levels are negatively correlated with protein and starch digestibility. However, phytic acid can be degraded by the action of the enzyme phytase. Phytase plays important roles in the degradation of phytic acid and in increasing the nutritional quality of staple foods. Microbial phytase is a versatile enzyme that is beneficial for humans, animals, the environment, and the industry. In this review, we summarise the interaction of phytic acid with micronutrients, various approaches to enhancing the nutritional profile of staple foods by reducing the phytic acid content, and current knowledge of microbial-based phytase as a potential reducer of phytic acid.

Integrated breeding approaches to enhance the nutritional quality of food legumes

Global food security, both in terms of quantity and quality remains as a challenge with the increasing population. In parallel, micronutrient deficiency in the human diet leads to malnutrition and several health-related problems collectively known as "hidden hunger" more prominent in developing countries around the globe. Biofortification is a potential tool to fortify grain legumes with micronutrients to mitigate the food and nutritional security of the ever-increasing population. Anti-nutritional factors like phytates, raffinose (RFO's), oxalates, tannin, etc. have adverse effects on human health upon consumption. Reduction of the anti-nutritional factors or preventing their accumulation offers opportunity for enhancing the intake of legumes in diet besides increasing the bioavailability of micronutrients. Integrated breeding methods are routinely being used to exploit the available genetic variability for micronutrients through modern "omic" technologies such as genomics, transcriptomics, ionomics, and metabolomics for developing biofortified grain legumes. Molecular mechanism of Fe/Zn uptake, phytate, and raffinose family oligosaccharides (RFOs) biosynthesis pathways have been elucidated. Transgenic, microRNAs and genome editing tools hold great promise for designing nutrient-dense and anti-nutrient-free grain legumes. In this review, we present the recent efforts toward manipulation of genes/QTLs regulating biofortification and Anti-nutrient accumulation in legumes using genetics-, genomics-, microRNA-, and genome editing-based approaches. We also discuss the success stories in legumes enrichment and recent advances in development of low Anti-nutrient lines. We hope that these emerging tools and techniques will expedite the efforts to develop micronutrient dense legume crop varieties devoid of Anti-nutritional factors that will serve to address the challenges like malnutrition and hidden hunger.

Understanding G × E Interaction for Nutritional and Antinutritional Factors in a Diverse Panel of Vigna stipulacea (Lam.) Kuntz Germplasm Tested Over the Locations

Micronutrient malnutrition or hidden hunger is a serious challenge toward societal well-being. Vigna stipulacea (Lam.) Kuntz (known locally as Minni payaru), is an underutilized legume that has the potential to be a global food legume due to its rich nutrient profile. In the present study, 99 accessions of V. stipulacea were tested for iron (Fe), zinc (Zn), calcium (Ca), protein, and phytate concentrations over two locations for appraisal of stable nutrient-rich sources. Analysis of variance revealed significant effects of genotype for all the traits over both locations. Fe concentration ranged from 29.35-130.96 mg kg-1 whereas Zn concentration ranged from 19.44 to 74.20 mg kg-1 across both locations. The highest grain Ca concentration was 251.50 mg kg-1 whereas the highest grain protein concentration was recorded as 25.73%. In the case of grain phytate concentration, a genotype with the lowest value is desirable. IC622867 (G-99) was the lowest phytate containing accession at both locations. All the studied traits revealed highly significant genotypic variances and highly significant genotype × location interaction though less in magnitude than the genotypic variance. GGE Biplot analysis detected that, for grain Fe, Zn, and Ca concentration the 'ideal' genotypes were IC331457 (G-75), IC331610 (G-76), and IC553564 (G-60), respectively, whereas for grain protein concentration IC553521 (G-27) was the most "ideal type." For phytate concentration, IC351407 (G-95) and IC550523 (G-99) were considered as 'ideal' and 'desirable,' respectively. Based on the desirability index, Location 1 (Kanpur) was identified as ideal for Fe, Zn, Ca, and phytate, and for grain protein concentration, Location 2 (New Delhi) was the ideal type. A significant positive correlation was detected between grain Fe as well as grain Zn and protein concentration considering the pooled analysis over both the locations where as a significant negative association was observed between phytate and protein concentration over the locations. This study has identified useful donors and enhanced our knowledge toward the development of biofortified Vigna cultivars. Promoting domestication of this nutrient-rich semi-domesticated, underutilized species will boost sustainable agriculture and will contribute toward alleviating hidden hunger.

Revisiting phytate-element interactions: implications for iron, zinc and calcium bioavailability, with emphasis on legumes

Myo-Inositol hexakisphosphate or phytic acid concentration is a prominent factor known to impede divalent element bioavailability in vegetal foods including legumes. Both in vivo and in vitro studies have suggested that phytic acid and other plant-based constituents may synergistically form insoluble complexes affecting bioavailability of essential elements. This review provides an overview of existing investigations on the role of phytic acid in the binding, solubility and bioavailability of iron, zinc and calcium with a focus on legumes. Given the presence of various interference factors within legume matrices, current findings suggest that the commonly adapted approach of using phytic acid-element molar ratios as a bioavailability predictor may only be valid in limited circumstances. In particular, differences between protein properties and molar concentrations of other interacting ions are likely responsible for the observed poor correlations. The role of phytate degradation in element bioavailability has been previously examined, and in this review we re-emphasize its importance as a tool to enhance mineral bioavailability of mineral fortified legume crops. Food processing strategies to achieve phytate reduction were identified as promising tools to increase mineral bioavailability and included germination and fermentation, particularly when other bioavailability promoters (e.g. NaCl) are simultaneously added.

Protein, Phytate and Minerals in Grains of Commercial Cowpea Genotypes

The objective of this study was to investigate and characterize cowpea (Vigna unguiculata) genotypes for total grain protein content, storage protein fractions (globulin, albumin, prolamin, basic and acid glutelins), and phytate and minerals contents. Eighteen cowpea genotypes were selected. Total grain protein content varied from 21.4% to 29.2%, for BRS Marataoã and Paulistinha genotypes, respectively. The variation in the concentration of each protein fraction was significant (P<0.05) only for glutelins (basic and acid). The genotypes studied exhibited great similarity in the PAGE electrophoretic profile of the grain protein fractions and also in the mineral content. BRS Paraguaçu genotype exhibited higher Zn content than thegenotypes that have been previously recommended for this characteristic. The lowest phytate grain content was observed in four of the 18 genotypes studied, which also exhibited high protein contents. Although the results did not converge to the selection of a few genotypes, some specific differences were detected that which may be further explored. Considering total grain protein, mineral and phytate contents, the genotype Paulistinha revealed a better balance unveiling high grain total protein content, low grain phytate content and more homogeneous mineral composition.

In silico genome-wide identification and characterization of the glutathione S-transferase gene family in Vigna radiata

Plant glutathione S-transferases (GSTs) are integral to normal plant metabolism and biotic and abiotic stress tolerance. The GST gene family has been characterized in diverse plant species using molecular biology and bioinformatics approaches. In the current study, in silico analysis identified 44 GSTs in Vigna radiata. Of the total 44 GSTs identified, chromosomal locations of 31 GSTs were confirmed. The pI value of GST proteins ranged from 5.10 to 9.40. The predicted molecular weights ranged from 13.12 to 50 kDa. Subcellular localization analysis revealed that all GSTs were predominantly localized in the cytoplasm. The active site amino acids were confirmed to be serine in tau, phi, theta, zeta, and TCHQD; cysteine in lambda, DHAR, and omega; and tyrosine in EF1G. The gene architecture conformed to the two-exon/one-intron and three-exon/two-intron organization in the case of tau and phi classes, respectively. MEME analysis identified 10 significantly conserved motifs with the width of 8-50 amino acids. The motifs identified were either specific to a specific GST class or were shared by multiple GST classes. The results of the current study will be of potential importance in the characterization of the GST gene family in V. radiata, an economically important leguminous crop.

Phytase from Citrobacter koseri PM-7: Enhanced production using statistical method and application in ameliorating mineral bioaccessibility and protein digestibility of high-phytate food

The present study was aimed at enhancing phytase (Phy-Ck) production from Citrobacter koseri PM-7 using response surface methodology (RSM) and improving the bioaccessibility of minerals (Fe and Zn) and protein digestibility in high-phytate food using Phy-Ck. A five-variable and three-level central composite design of RSM using wheat bran (6.681%, w/v), inoculum level (2.5%, v/v), and triton X-100 (0.2%, v/v) resulted in up to 5.57-fold (1.047 U/ml) improvement in Phy-Ck yield from C. koseri PM-7 when compared with fermentation media I and II. The model was successfully validated in the design space by taking a random set of variable combinations. Treatment of high-phytate food with partially purified Phy-Ck showed improvement in mineral bioaccessibility maximally for defatted sesame flour (DSF) (Fe 45.5%; Zn 50.7%) followed by wheat flour (WF) (Fe 13.5%; Zn 14.4%), green gram flour (GGF) (Fe 0.7%; Zn 3.8%) and defatted groundnut flour (DGF) (Zn 5.6%). The in vitro protein digestibility (IVPD) of WF increased from 48.83 to 65.04%, GGF from 45.04 to 57.12%, and DSF from 47.34 to 55.7% after Phy-Ck treatment.

Identification of chickpea seed proteins resistant to simulated in vitro human digestion

Proteins and peptides able to resist gastrointestinal digestion and reach the intestinal mucosa have the potential to influence human health. Chickpea (Cicer arietinum L.) seed proteins are able to resist cooking (86.9% total protein) and/or in vitro simulated human digestion (15.9% total protein resists soaking, cooking and digestion with pepsin and pancreatin). To identify and characterize proteins resisting digestion we made use of different MS methodologies. The efficiency of several proteases (trypsin, AspN, chymotrypsin and LysC) was tested, and two technologies were employed (MALDI-MS/MS and LC-nESI-MS/MS). Digestion with trypsin and AspN were most successful for the identification of seed proteins. When analyzed by MALDI- MS/MS, trypsin allowed the identification of at least one protein in 60% of the polypeptide bands, while AspN allows the identification in 48%. The use of LC-nESI-MS/MS, allowed the identification of much more proteins/polypeptides from digested seeds (232 vs 17 using trypsin). The majority of the proteins found to be able to resist simulated digestion were members of the 7S vicilin and 11S legumin seed storage protein classes, which are reported to contain bio-active functions. In addition, we have found proteins that had not yet been described as potentially able to cause an impact on human health.

SIGNIFICANCE

This is the first proteomic study to analyze the effect of processing and simulated human gastrointestinal digestion on the proteome of chickpea seed. Chickpea is reported to have anti-nutritional effects as well as nutraceutical properties, so the identification and characterization of the proteins able to resist digestion is crucial to understand the targets underlying such properties.

The impact of using chickpea flour and dried carp fish powder on pizza quality

Pizza being the most popular food worldwide, quality and sensory appeal are important considerations during its modification effort. This study was aimed to evaluate the quality of pizza made using two different sources of proteins, chickpea (Cicer arietinum) flour and dried carp fish powder (Cyprinus carpio). Analysis indicated nutrients richness specificity of chickpea flour (higher fiber, energy, iron, zinc, linoleic acid and total nonessential amino acids) and dried carp fish powder (higher contents of protein, fats, ash, oleic acid and total essential amino acids) complementing wheat flour to enhance nutritional value of pizza. Total plate count and thiobarbituric acid were increased (P<0.05) in dried carp fish powder after 45 days of storage, but no Coliform were detected. Wheat flour was substituted with 5, 7.5 and 10% chickpea flour or dried carp fish powder and chemical, textural, sensory and storage evaluation parameters of in pizza were investigated. Dried carp fish powder increased (P<0.05) contents of protein, ash, fats, zinc and protein digestibility of pizza. Chickpea flour increased iron and zinc contents of the pizza. Water activity (a_w) was decreased in fish powder and chickpea pizza. Pizza firmness and gumminess were significantly (p<0.05) increased at every level of protein source, but cohesiveness was decreased with 10% chickpea flour. Pizza chewiness was the same (P>0.05) across the levels of two protein sources. Springiness was decreased (P<0.05) with high level (10%) dried fish powder and low/intermediate level of chickpea flour. Chickpea and dried carp fish incorporation up to 7.50% in pizza at the expense of wheat flour had no effect (P>0.05) on all sensorial parameters except for odor values. The results could be useful in utilization of chickpea flour and carp fish powder in designing nutritious pizza for consumers.

Impact of a novel synbiotic supplementation during gestation and lactation on immune responses in the Swiss albino mice offspring

BACKGROUND

Prebiotics from various regularly consumed cereals and novel substrates are currently being utilised as functional foods. The aim of this study was to determine the effect of synbiotic, formulated with prebiotic extracted from natural resources like green gram (Vigna radiata) along with probiotic Lactobacillus rhamnosus GG (LGG) in modulating immune responses in the offspring when supplemented during gestation and lactation.

RESULTS

Synbiotic supplementation was effective in improving cell mediated immunity and humoral immunity among F0 dams. Among F1 pups (F1 Syn + and F1 Syn-), synbiotic supplementation showed significantly heightened (P < 0.05) splenocyte proliferation, increased interleukin-10, interferon gamma and interleukin-17 responses, leucocyte phagocytic ability and increased secretory-immunoglobulin A. However, four-fold increase in IgG titres to Hepatitis-B vaccine was observed only in those mice that were supplemented with synbiotic postweaning (F1 Syn+).

CONCLUSION

Synbiotic supplementation to pregnant dams affected the offspring's cellular and mucosal immunity favorably. However, IgG response to Hepatitis-B vaccine was influenced positively only when the supplementation was extended to the offsprings in the post weaning period. © 2016 Society of Chemical Industry.

Genetic variability for iron and zinc as well as antinutrients affecting bioavailability in black gram (Vigna mungo (L.) Hepper)

The mineral content of pulses is generally high, but the bioavailability is poor due to the presence of phytate and polyphenols which inhibits Fe absorption. In the present study, the genetic variability and heritability for seed Fe and Zn content was studied. The effect of genotypes was significant for all the quality traits indicating presence of enough variability among the blackgram genotypes for the traits. The Fe content in 26 blackgram genotypes ranged from 71.02 to 100.20 ppm, whereas Zn content ranged from 18.93 to 60.58 ppm. Maximum Fe as well as Zn was recorded in genotype SHEKHAR 2 (100.2 and 60.58 ppm respectively). The Phytic acid and polyphenol content among genotypes varied significantly and it ranged from 0.06-0.37% to 5.88-9.03 mg/g, respectively. High phytic acid content was recorded in black gram genotypes COBG 653, Nodai Urd, NP 03 and PKG U 03, whereas high polyphenol content was recorded in PU 31, IPU 99-200, PDU 1 and YAKUBPUR 2. Blackgram genotype COBG 653 had high phytic acid but low polyphenol content. The genotype × year interaction was significant for all the traits under study which indicates differential reaction to the expression of quality characters over years. Fe content in blackgram genotypes showed significant positive phenotypic correlation with Zn content while at genotypic level in addition to Zn, it showed positive correlation with phytic acid and polyphenol content as well. This indicates that although the traits are genotypically correlated, the expression is masked by the environmental influence. This is further exhibited from low heritability estimates for phytic acid and polyphenol content among the genotypes.

Finger on the Pulse: Pumping Iron into Chickpea

Iron deficiency is a major problem in both developing and developed countries, and much of this can be attributed to insufficient dietary intake. Over the past decades several measures, such as supplementation and food fortification, have helped to alleviate this problem. However, their associated costs limit their accessibility and effectiveness, particularly amongst the financially constrained. A more affordable and sustainable option that can be implemented alongside existing measures is biofortification. To date, much work has been invested into staples like cereals and root crops-this has culminated in the successful generation of high iron-accumulating lines in rice and pearl millet. More recently, pulses have gained attention as targets for biofortification. Being secondary staples rich in protein, they are a nutritional complement to the traditional starchy staples. Despite the relative youth of this interest, considerable advances have already been made concerning the biofortification of pulses. Several studies have been conducted in bean, chickpea, lentil, and pea to assess existing germplasm for high iron-accumulating traits. However, little is known about the molecular workings behind these traits, particularly in a leguminous context, and biofortification via genetic modification (GM) remains to be attempted. This review examines the current state of the iron biofortification in pulses, particularly chickpea. The challenges concerning biofortification in pulses are also discussed. Specifically, the potential application of transgenic technology is explored, with focus on the genes that have been successfully used in biofortification efforts in rice.

Repeat length variation in the 5'UTR of myo-inositol monophosphatase gene is related to phytic acid content and contributes to drought tolerance in chickpea (Cicer arietinum L.)

Myo-inositol metabolism plays a significant role in plant growth and development, and is also used as a precursor for many important metabolites, such as ascorbate, pinitol, and phytate. Phytate (inositol hexakisphosphate) is the major storage pool for phosphate in the seeds. It is utilized during seed germination and growth of the developing embryo. In addition, it is implicated in protection against oxidative stress. In the present study, a panel of chickpea accessions was used for an association analysis. Association analysis accounting for population structure and relative kinship identified alleles of a simple sequence repeat marker, NCPGR90, that are associated with both phytic acid content and drought tolerance. These alleles varied with respect to the dinucleotide CT repeats present within the marker. NCPGR90 located to the 5'UTR of chickpea myo-inositol monophosphatase gene (CaIMP) and showed transcript length variation in drought-tolerant and drought-susceptible accessions. CaIMP from a drought-tolerant accession with a smaller repeat was almost 2-fold upregulated as compared to a susceptible accession having a longer repeat, even under control non-stressed conditions. This study suggests an evolution of simple sequence repeat length variation in CaIMP, which might be regulating phytic acid levels to confer drought tolerance in natural populations of chickpea.

The AVRDC - The World Vegetable Center mungbean (Vigna radiata) core and mini core collections

Background

Large ex situ germplasm collections generally harbor a wide range of crop diversity. AVRDC – The World Vegetable Center is holding in trust the world’s second largest mungbean (Vigna radiata) germplasm collection with more than 6,700 accessions. Screening large collections for traits of interest is laborious and expensive. To enhance the access of breeders to the diversity of the crop, mungbean core and mini core collections have been established.

Results

The core collection of 1,481 entries has been built by random selection of 20% of the accessions after geographical stratification and subsequent cluster analysis of eight phenotypic descriptors in the whole collection. Summary statistics, especially the low differences of means, equal variance of the traits in both the whole and core collection and the visual inspection of quantile-quantile plots comparing the variation of phenotypic traits present in both collections indicated that the core collection well represented the pattern of diversity of the whole collection. The core collection was genotyped with 20 simple sequence repeat markers and a mini core set of 289 accessions was selected, which depicted the allele and genotype diversity of the core collection.

Conclusions

The mungbean core and mini core collections plus their phenotypic and genotypic data are available for distribution to breeders. It is expected that these collections will enhance the access to biodiverse mungbean germplasm for breeding.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1556-7) contains supplementary material, which is available to authorized users.

Horse gram- an underutilized nutraceutical pulse crop: a review

Horse gram is an underutilized pulse crop grown in wide range of adverse climatic conditions. It occupies an important place in human nutrition and has rich source of protein, minerals, and vitamins. Besides nutritional importance, it has been linked to reduced risk of various diseases due to presence of non-nutritive bioactive substances. These bioactive substances such as phytic acid, phenolic acid, fiber, enzymatic/proteinase inhibitors have significant metabolic and/or physiological effects. The importance of horse gram was well recognized by the folk/alternative/traditional medicine as a potential therapeutic agent to treat kidney stones, urinary diseases, piles, common cold, throat infection, fever etc. The inception of nutraceutical concept and increasing health consciousness the demand of nutraceutical and functional food is increased. In recent years, isolation and utilization of potential antioxidants from legumes including horse gram are increased as it decreases the risk of intestinal diseases, diabetes, coronary heart disease, prevention of dental caries etc. Keeping in view the increasing demand of food having nutraceutical values, the present review ascribed with recent scientific knowledge towards the possibilities of exploring the horse gram, as a source of food and nutraceuticals compounds.

Biofortification of mungbean (Vigna radiata) as a whole food to enhance human health

Mungbean (Vigna radiata (L.) R. Wilczek var. radiata) is one of the most important pulse crops grown in South, East and Southeast Asia. It provides significant amounts of protein (240 g kg(-1)) and carbohydrate (630 g kg(-1)) and a range of micronutrients in diets. Mungbean protein and carbohydrate are easily digestible and create less flatulence than proteins derived from other legumes. In addition, mungbean is lower in phytic acid (72% of total phosphorus content) than pigeonpea (Cajanus cajan L. Millsp.), soybean (Glycine max L.) and cereals; phytic acid is commonly found in cereal and legume crops and has a negative impact on iron and zinc bioavailability in plant-based diets. Owing to its palatable taste and nutritional quality, mungbean has been used as an iron-rich whole food source for baby food. The wide genetic variability of mineral concentrations (e.g. 0.03-0.06 g Fe kg(-1), 0.02-0.04 g Zn kg(-1)) in mungbean indicates possibilities to improve its micronutrient content through biofortification. Therefore biofortification of existing mungbean varieties has great potential for enhancing the nutritional quality of diets in South and Southeast Asia, where protein and micronutrient malnutrition are among the highest in the world. This review paper discusses the importance of mungbean in agricultural production and traditional diets and the potential of enhancing the nutritional quality of mungbean through breeding and other means, including agronomic practices.

Impact of antinutritional factors in food proteins on the digestibility of protein and the bioavailability of amino acids and on protein quality

Dietary antinutritional factors have been reported to adversely affect the digestibility of protein, bioavailability of amino acids and protein quality of foods. Published data on these negative effects of major dietary antinutritional factors are summarized in this manuscript. Digestibility and the quality of mixed diets in developing countries are considerably lower than of those in developed regions. For example, the digestibility of protein in traditional diets from developing countries such as India, Guatemala and Brazil is considerably lower compared to that of protein in typical North American diets (54-78 versus 88-94 %). Poor digestibility of protein in the diets of developing countries, which are based on less refined cereals and grain legumes as major sources of protein, is due to the presence of less digestible protein fractions, high levels of insoluble fibre, and/or high concentrations of antinutritional factors present endogenously or formed during processing. Examples of naturally occurring antinutritional factors include glucosinolates in mustard and canola protein products, trypsin inhibitors and haemagglutinins in legumes, tannins in legumes and cereals, gossypol in cottonseed protein products, and uricogenic nucleobases in yeast protein products. Heat/alkaline treatments of protein products may yield Maillard reaction compounds, oxidized forms of sulphur amino acids, D-amino acids and lysinoalanine (LAL, an unnatural nephrotoxic amino acid derivative). Among common food and feed protein products, soyabeans are the most concentrated source of trypsin inhibitors. The presence of high levels of dietary trypsin inhibitors from soyabeans, kidney beans or other grain legumes have been reported to cause substantial reductions in protein and amino acid digestibility (up to 50 %) and protein quality (up to 100 %) in rats and/or pigs. Similarly, the presence of high levels of tannins in sorghum and other cereals, fababean and other grain legumes can cause significant reductions (up to 23 %) in protein and amino acid digestibility in rats, poultry, and pigs. Normally encountered levels of phytates in cereals and legumes can reduce protein and amino acid digestibility by up to 10 %. D-amino acids and LAL formed during alkaline/heat treatment of lactalbumin, casein, soya protein or wheat protein are poorly digestible (less than 40 %), and their presence can reduce protein digestibility by up to 28 % in rats and pigs, and can cause a drastic reduction (100 %) in protein quality, as measured by rat growth methods. The adverse effects of antinutritional factors on protein digestibility and protein quality have been reported to be more pronounced in elderly rats (20-months old) compared to young (5-weeks old) rats, suggesting the use of old rats as a model for assessing the protein digestibility of products intended for the elderly.

Nutritional quality and health benefits of chickpea (Cicer arietinumL.): a review

Chickpea (Cicer arietinumL.) is an important pulse crop grown and consumed all over the world, especially in the Afro-Asian countries. It is a good source of carbohydrates and protein, and protein quality is considered to be better than other pulses. Chickpea has significant amounts of all the essential amino acids except sulphur-containing amino acids, which can be complemented by adding cereals to the daily diet. Starch is the major storage carbohydrate followed by dietary fibre, oligosaccharides and simple sugars such as glucose and sucrose. Although lipids are present in low amounts, chickpea is rich in nutritionally important unsaturated fatty acids such as linoleic and oleic acids. β-Sitosterol, campesterol and stigmasterol are important sterols present in chickpea oil. Ca, Mg, P and, especially, K are also present in chickpea seeds. Chickpea is a good source of important vitamins such as riboflavin, niacin, thiamin, folate and the vitamin A precursor β-carotene. As with other pulses, chickpea seeds also contain anti-nutritional factors which can be reduced or eliminated by different cooking techniques. Chickpea has several potential health benefits, and, in combination with other pulses and cereals, it could have beneficial effects on some of the important human diseases such as CVD, type 2 diabetes, digestive diseases and some cancers. Overall, chickpea is an important pulse crop with a diverse array of potential nutritional and health benefits.

An estimate of phytate intake and molar ratio of phytate to zinc in the diet of the people in the United Kingdom

Objective

To estimate the phytate intake and molar ratio of phytate to zinc in the diet of the people in the United Kingdom.

Design

Tables of the phytate content of foods were developed from twenty-eight published and unpublished studies. They were then applied to the nutrient databank of the National Diet and Nutrition Survey (NDNS). The study is a retrospective analysis of data on daily consumption of foods and drinks from the NDNS of children, adolescents, adults and the elderly based on 4–7 d weighed intakes.

Subjects

A total of 6786 British participants aged 1·5 years and above, who participated in the NDNS, 1992–2001.

Setting

England, Scotland and Wales.

Results

The median daily intakes of phytate for children, adolescents, adults and the elderly population were 496, 615, 809 and 629 mg/d, respectively. Although there were differences in phytate intakes between men and women, and for children, adolescents and elderly populations, after adjusting for differences in energy intake, there was no significant variation. The median phytate-to-zinc molar ratios for children, adolescents, adults and the elderly population were 11·8, 10·4, 9·7 and 8·7, respectively. Overall, the main sources of phytate were cereal and cereal products (e.g. breakfast cereals and breads), vegetables, potatoes and savoury snacks (e.g. chips and crisps), hot drinks and miscellaneous foods (e.g. commercial toddler foods and drinks, chocolate and soups), fruits and nuts.

Conclusions

The present study estimated the dietary intake of phytate and the phytate-to-zinc molar ratio of the diet of the UK population, which can be used for estimating the average requirement of zinc. Further research should focus on the completion and validation of the tables of phytate content of UK foods, to assess (and if necessary improve) the accuracy and precision of these findings.