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.

The mineral content of pulses grown in Saskatchewan, Canada, was examined for magnesium, potassium, iron, zinc, manganese, copper, selenium, and in some cases nickel and calcium. Eight to 18 cultivars of each of field pea (Pisum sativum), common bean (Phaseolus vulgaris), chickpea (Cicer arietinum), and lentil (Lens culinaris) were grown at several locations in southern Saskatchewan in 2005 and 2006 in randomized complete block designs with three replicates. Mineral content was examined by atomic absorption spectrometry. The pulses were found to contain significant proportions of the recommended daily allowance (RDA) for all the tested minerals except calcium. In many cases a 100 g (dry weight) portion of the crop provided over 50% of the RDA. For selenium, pulses grown in some locations provided 100% of the RDA. The effect of location was highly significant in most instances, while that of year and cultivar were generally less so. Pairwise differences among cultivars were examined by Tukey's test. Where possible, crops grown side by side were compared.

Beneficial forms of selenium (Se) and their impact on human health are a global topic of interest in public health. We are studying the genetic potential for Se biofortification of pulse crops to improve human nutrition. Lentils ( Lens culinaris L.) are an important protein and carbohydrate food and are a valuable source of essential dietary components and trace elements. We analyzed the total Se concentration of 19 lentil genotypes grown at eight locations for two years in Saskatchewan, Canada. We observed significant genotypic and environmental variation in total Se concentration in lentils and that total Se concentration in lentils ranged between 425 and 673 microg kg(-1), providing 77-122% of the recommended daily intake in 100 g of dry lentils. Over 70% of the Se was present as selenomethionine (SeMet) with a smaller fraction (<20%) as inorganic Se and very small amounts as selenocysteine (SeCys). We found that soils from the locations where the lentils were grown were rich in Se (37-301 microg kg(-1)) and that lentils grown in Saskatchewan have the potential to provide an excellent natural source of this essential element. Our analyses gave us a preliminary understanding of the genetic basis of Se uptake in lentil and indicated that any potential strategy for micronutrient biofortification in lentil will require choice of field locations that minimize the spatial variability of soil Se content.

Micronutrient malnutrition, the hidden hunger, affects more than 40% of the world's population, and a majority of them are in South and South East Asia and Africa. This study was carried out to determine the potential for iron (Fe) and zinc (Zn) biofortification of lentils ( Lens culinaris Medikus subsp. culinaris ) to improve human nutrition. Lentils are a common and quick-cooking nutritious staple pulse in many developing countries. We analyzed the total Fe and Zn concentrations of 19 lentil genotypes grown at eight locations for 2 years in Saskatchewan, Canada. It was observed that some genetic variation exists for Fe and Zn concentrations among the lentil lines tested. The total Fe and Zn concentrations ranged from 73 to 90 mg of Fe kg(-1) and from 44 to 54 mg of Zn kg(-1). The calculated percentages of the recommended daily allowance (RDA) for Fe and Zn were within the RDA ranges from a 100 g serving of dry lentils. Broad-sense heritability estimates for Fe and Zn concentrations in lentil seed were 64 and 68%, respectively. It was concluded that lentils have great potential as a whole food source of Fe and Zn for people affected by these nutrient deficiencies. This is the first report on the genetic basis for Fe and Zn micronutrient content in lentils. These results provide some understanding of the genetic basis of Fe and Zn concentrations and will allow for the development of potential strategies for genetic biofortification.

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Phytic acid is an antinutrient present mainly in seeds of grain crops such as legumes and cereals. It has the potential to bind mineral micronutrients in food and reduce their bioavailability. This study analyzed the phytic acid concentration in seeds of 19 lentil ( Lens culinaris L.) genotypes grown at two locations for two years in Saskatchewan, Canada. The objectives of this study were to determine (1) the levels of phytic acid in commercial lentil genotypes and (2) the impact of postharvest processing and (3) the effect of boiling on the stability of phytic aid in selected lentil genotypes. The phytic acid was analyzed by high-performance anion exchange separation followed by conductivity detection. The Saskatchewan-grown lentils were naturally low in phytic acid (phytic acid = 2.5-4.4 mg g(-1); phytic acid phosphorus = 0.7-1.2 mg g(-1)), with concentrations lower than those reported for low phytic acid mutants of corn, wheat, common bean, and soybean. Decortication prior to cooking further reduced total phytic acid by >50%. As lowering phytic acid intake can lead to increased mineral bioavailability, dietary inclusion of Canadian lentils may have significant benefits in regions with widespread micronutrient malnutrition.

Micronutrient malnutrition, especially selenium (Se), iron (Fe), and zinc (Zn) deficiency, is a major global health problem. Previous attempts to prevent micronutrient malnutrition through food fortification, supplementation, and enrichment of staple crops has had limited success. Canadian grown lentils are rich in micronutrients Fe (73-90 mg kg -1 ), Zn (44-54 mg kg -1 ), Se (425-673 lg kg -1 ), and have very low concentrations of phytic acid (2.5-4.4 mg g -1 ). Our preliminary studies using a Caco-2 cell model show that the uptake of Fe from lentils is relatively greater than that of most other staple food crops. Moreover, preliminary results from our human nutrition study in Sri Lanka show an increased trend in blood Se concentration after lentil consumption. This article briefly overviews our previously published results as well as data from international lentil field trials, and describes the potential for biofortified lentil to provide a whole food solution to combat global human micronutrient malnutrition.

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