Lentil (Lens culinaris Medikus): A Whole Food Rich in Prebiotic Carbohydrates to Combat Global Obesity

Lentil (Lens culinaris Medik.) is a cool season food legume that is high in protein (20–30%) and in a range of micronutrients (e.g., minerals, carotenoids, folates) but very low in phytic acid. Recent research indicates that lentil contains a wide array of low-molecular weight carbohydrates (LMWC) or prebiotic carbohydrates, such as mono- and disaccharides, raffinose-family oligosaccharides (RFO), fructooligosaccharides (FOS), and sugar alcohols, and high-molecular weight resistant starches. Lentil provides more than 13 g of prebiotic carbohydrates per 100 g serving, and this level increases almost two-fold upon cooking, cooling, and reheating. In addition, prebiotic carbohydrate levels vary with lentil genotype and growing location/country. Intestinal microbiome and prebiotic studies suggest a prebiotic-rich, low-calorie diet can reduce the prevalence of obesity and related non-communicable diseases. Lentil thus represents a whole food source of prebiotics that can play a role in efforts to reduce obesity and non-communicable diseases. This chapter provides an overview of the current obesity-related health issues, holistic approaches to reduce obesity, worldwide lentil production, and the promise of pulses, mainly lentil, to be a whole food solution to combat global obesity. In addition, lentil’s superior LMWC profile and the genetic potential for further enrichment of prebiotic carbohydrates are briefly discussed

Variability in Prebiotic Carbohydrates in Different Market Classes of Chickpea, Common Bean, and Lentil Collected From the American Local Market

Pulse crops such as lentil, common bean, and chickpea are rich in protein, low digestible carbohydrates, and range of micronutrients. The detailed information of low digestible carbohydrates also known as “prebiotic carbohydrate” profiles of commonly consumed pulse market classes and their impact on human health are yet to be studied. The objective of this study was to determine the profiles of prebiotic carbohydrates in two commonly consumed lentil market classes, seven common bean market classes, and two chickpea market classes. After removing fat and protein, total carbohydrates averaged 51/100 g for lentil, 53/100 g for common bean, and 54/100 g for chickpea. Among the portion of total carbohydrates, lentil showed 12/100 g of prebiotic carbohydrates (sugar alcohols, raffinose family oligosaccharides, fructooligosaccharides, hemicellulose, cellulose, and resistant starch), 15/100 g in common bean, and 12/100 g in chickpea. Prebiotic carbohydrate concentrations within the market classes for each crop were significantly different (P < 0.05). In conclusion, these three pulses are rich in prebiotic carbohydrates, and considering the variation in these concentrations in the present materials, it is possible to breed appropriate market classes of pulses with high levels of prebiotic carbohydrates

Effect of High Temperature Stress During the Reproductive Stage on Grain Yield and Nutritional Quality of Lentil (Lens culinaris Medikus)

High temperature during the reproductive stage limits the growth and development of lentil (Lens culinaris Medikus). The reproductive and seed filling periods are the most sensitive to heat stress, resulting in limited yield and nutritional quality. Climate change causes frequent incidents of heat stress for global food crop production. This study aimed to assess the impact of high temperature during the reproductive stage of lentil on grain yield, nutritional value, and cooking quality. Thirty-six lentil genotypes were evaluated under controlled conditions for their high temperature response. Genotypic variation was significant (p < 0.001) for all the traits under study. High temperature-induced conditions reduced protein, iron (Fe) and zinc (Zn) concentrations in lentils. Under heat stress conditions, mineral concentrations among lentil genotypes varied from 6.0 to 8.8 mg/100 g for Fe and from 4.9 to 6.6 mg/100 g for Zn. Protein ranged from 21.9 to 24.3 g/100 g. Cooking time was significantly reduced due to high temperature treatment; the range was 3–11 min, while under no stress conditions, cooking time variation was from 5 to 14 min. Phytic acid variation was 0.5–1.2 g/100 g under no stress conditions, while under heat stress conditions, phytic acid ranged from 0.4 to 1.4 g/100 g. All genotypes had highly significant bioavailable Fe and moderately bioavailable Zn under no stress conditions. Whereas under heat stress conditions, Fe and Zn bioavailability was reduced due to increased phytic acid levels. Our results will greatly benefit the development of biofortified lentil cultivars for global breeding programs to generate promising genotypes with low phytic acid and phytic acid/micronutrient ratio to combat micronutrient malnutrition

Lentil and Kale: Complementary Nutrient-Rich Whole Food Sources to Combat Micronutrient and Calorie Malnutrition

Lentil (Lens culinaris Medik.) is a nutritious food and a staple for millions of people. Not only are lentils a good source of energy, they also contain a range of micronutrients and prebiotic carbohydrates. Kale (Brassica oleracea v. acephala) has been considered as a health food, but its full range of benefits and composition has not been extensively studied. Recent studies suggest that foods are enrich in prebiotic carbohydrates and dietary fiber that can potentially reduce risks of non-communicable diseases, including obesity, cancer, heart disease, and diabetes. Lentil and kale added to a cereal-based diet would enhance intakes of essential minerals and vitamins to combat micronutrient malnutrition. This review provides an overview of lentil and kale as a complementary nutrient-rich whole food source to combat global malnutrition and calorie issues. In addition, prebiotic carbohydrate profiles and the genetic potential of these crops for further micronutrient enrichment are briefly discussed with respect to developing sustainable and nutritious food systems

Fourier‐transform infrared spectroscopy (FTIR) as a high‐throughput phenotyping tool for quantifying protein quality in pulse crops

Abstract Fourier‐transform mid‐infrared (FT‐MIR) spectroscopy is a high‐throughput, cost‐effective method to quantify nutritional traits, such as total protein and sulfur‐containing amino acid (SAA) concentrations, in plant matter. This study used the spectroscopic technique FT‐MIR coupled with attenuated total internal reflectance sampling interface to develop multivariate models for total protein concentration in chickpea (Cicer arietinum L.), dry pea (Pisum sativum L.), and lentil (Lens culinaris Medik.), in addition to SAA concentration in lentil. Total nitrogen data from combustion analysis and SAA data from high‐performance liquid chromatography analysis following acid hydrolysis were used for model calibration and validation. Models for the total protein concentration of chickpea (calibration root mean square error [RMSE] = 0.093, R2 = 0.948, prediction RMSE = 0.10), dry pea (calibration RMSE = 0.096, R2 = 0.845, prediction RMSE = 0.093), and lentil (calibration RMSE = 0.13, R2 = 0.845, prediction RMSE = 0.11) utilized infrared regions associated with protein structures, namely amide bands A, I, and II. In sulfur‐related models for lentil total SAA (calibration RMSE = 0.014, R2 = 0.827, prediction RMSE = 0.022) and methionine (calibration RMSE = 0.0075, R2 = 0.815, prediction RMSE = 0.014) models utilized the C‐S and S‐CH3 stretching and bending bands. Study findings support the conclusion that FT‐MIR spectroscopy is a promising high‐throughput and cost‐effective phenotyping technique that will allow quantifying protein traits quickly and easily in pulse crops

Fourier‐transform infrared spectroscopy: An inexpensive, rapid, and less‐destructive tool for starch and resistant starch analysis from pulse flour

Abstract Pulse crops are a rich source of resistant starch (RS) (5–7 g/100 g), a prebiotic carbohydrate that promotes gut health. The standard method to measure total starch (TS) and RS is through enzymatic assay; however, this is both time consuming and expensive. Fourier‐transform mid‐infrared (FT‐MIR) spectroscopy is a high‐throughput, cost‐effective method to quantify nutritional traits in seeds, but models have not been developed for starch in pulse crops. Therefore, this study aimed to develop and validate an FT‐MIR chemometric technique to estimate TS and RS in dry pea (Pisum sativum L.), chickpea (Cicer arietinum L.), and lentil (Lens culinaris, Medikus) flours to accelerate global pulse breeding efforts, support industrial carbohydrate utilization, and develop healthier food‐feed calorie contents. Breeding lines were selected to capture the diversity of starch concentrations in each crop and were analyzed using an enzymatic assay. Models for each trait–crop combination were calibrated using partial least squares regression, resulting in R2 and root means square error of prediction ranging from 0.91 to 0.96 and 0.16 to 4.0 g/100 g, respectively. These results demonstrate that FT‐MIR spectroscopy is a promising tool for estimating TS and RS concentrations in pulse crops at a reduced analysis time and cost, expediting plant breeding and starch use efforts in the food processing industry

Selecting Lentil Accessions for Global Selenium Biofortification

The biofortification of lentil (Lens culinaris Medikus.) has the potential to provide adequate daily selenium (Se) to human diets. The objectives of this study were to (1) determine how low-dose Se fertilizer application at germination affects seedling biomass, antioxidant activity, and Se uptake of 26 cultivated lentil genotypes; and (2) quantify the seed Se concentration of 191 lentil wild accessions grown in Terbol, Lebanon. A germination study was conducted with two Se treatments [0 (control) and 30 kg of Se/ha] with three replicates. A separate field study was conducted in Lebanon for wild accessions without Se fertilizer. Among cultivated lentil accessions, PI533690 and PI533693 showed &gt;100% biomass increase vs. controls. Se addition significantly increased seedling Se uptake, with the greatest uptake (6.2 µg g−1) by PI320937 and the least uptake (1.1 µg g−1) by W627780. Seed Se concentrations of wild accessions ranged from 0 to 2.5 µg g−1; accessions originating from Syria (0–2.5 µg g−1) and Turkey (0–2.4 µg g−1) had the highest seed Se. Frequency distribution analysis revealed that seed Se for 63% of accessions was between 0.25 and 0.75 µg g−1, and thus a single 50 g serving of lentil has the potential to provide adequate dietary Se (20–60% of daily recommended daily allowance). As such, Se application during plant growth for certain lentil genotypes grown in low Se soils may be a sustainable Se biofortification solution to increase seed Se concentration. Incorporating a diverse panel of lentil wild germplasm into Se biofortification programs will increase genetic diversity for effective genetic mapping for increased lentil seed Se nutrition and plant productivity

Fatty acid composition and genome-wide associations of a chickpea (Cicer arietinum L.) diversity panel for biofortification efforts

Abstract Chickpea is a nutritionally dense pulse crop with high levels of protein, carbohydrates, micronutrients and low levels of fats. Chickpea fatty acids are associated with a reduced risk of obesity, blood cholesterol, and cardiovascular diseases in humans. We measured four primary chickpea fatty acids; palmitic acid (PA), linoleic acid (LA), alpha-linolenic acid (ALA), and oleic acid (OA), which are crucial for human health and plant stress responses in a chickpea diversity panel with 256 accessions (Kabuli and desi types). A wide concentration range was found for PA (450.7–912.6 mg/100 g), LA (1605.7–3459.9 mg/100 g), ALA (416.4–864.5 mg/100 g), and OA (1035.5–1907.2 mg/100 g). The percent recommended daily allowances also varied for PA (3.3–6.8%), LA (21.4–46.1%), ALA (34.7–72%), and OA (4.3–7.9%). Weak correlations were found among fatty acids. Genome-wide association studies (GWAS) were conducted using genotyping-by-sequencing data. Five significant single nucleotide polymorphisms (SNPs) were identified for PA. Admixture population structure analysis revealed seven subpopulations based on ancestral diversity in this panel. This is the first reported study to characterize fatty acid profiles across a chickpea diversity panel and perform GWAS to detect associations between genetic markers and concentrations of selected fatty acids. These findings demonstrate biofortification of chickpea fatty acids is possible using conventional and genomic breeding techniques, to develop superior cultivars with better fatty acid profiles for improved human health and plant stress responses