Polyphenolic Profiles of Yellow Bean Seed Coats and Their Relationship with Iron Bioavailability

Polyherbal and Multimodal Treatments: Kaempferol- and Quercetin-Rich Herbs Alleviate Symptoms of Alzheimer's Disease

Alzheimer's Disease (AD) is a progressive neurodegenerative disorder impairing cognition and memory in the elderly. This disorder has a complex etiology, including senile plaque and neurofibrillary tangle formation, neuroinflammation, oxidative stress, and damaged neuroplasticity. Current treatment options are limited, so alternative treatments such as herbal medicine could suppress symptoms while slowing cognitive decline. We followed PRISMA guidelines to identify potential herbal treatments, their associated medicinal phytochemicals, and the potential mechanisms of these treatments. Common herbs, including Ginkgo biloba, Camellia sinensis, Glycyrrhiza uralensis, Cyperus rotundus, and Buplerum falcatum, produced promising pre-clinical results. These herbs are rich in kaempferol and quercetin, flavonoids with a polyphenolic structure that facilitate multiple mechanisms of action. These mechanisms include the inhibition of Aβ plaque formation, a reduction in tau hyperphosphorylation, the suppression of oxidative stress, and the modulation of BDNF and PI3K/AKT pathways. Using pre-clinical findings from quercetin research and the comparatively limited data on kaempferol, we proposed that kaempferol ameliorates the neuroinflammatory state, maintains proper cellular function, and restores pro-neuroplastic signaling. In this review, we discuss the anti-AD mechanisms of quercetin and kaempferol and their limitations, and we suggest a potential alternative treatment for AD. Our findings lead us to conclude that a polyherbal kaempferol- and quercetin-rich cocktail could treat AD-related brain damage.

Genome-wide association analysis of anthracnose resistance in the Yellow Bean Collection of Common Bean

Anthracnose caused by Colletotrichum lindemuthianum is a major disease of common bean (Phaseolus vulgaris) worldwide. Yellow beans are a major market class of common bean especially in eastern and southern Africa. The Yellow Bean Collection (YBC), which is comprised of 255 genotypes, and has not been used previously in genetic studies on anthracnose, is an excellent genetic resource for understanding the extent of anthracnose resistance and its genetic architecture in the yellow bean market class. The objectives of this study were i) evaluate the YBC for resistance to races 5, 19, 39, 51, 81, 183, 1050 and 1105 of C. lindemuthianum. and ii) conduct genome-wide association analysis to identify genomic regions and candidate genes associated with resistance to C. lindemuthianum. The YBC was genotyped with 72,866 SNPs, and genome-wide association analysis was conducted using Mixed Linear Model in TASSEL. Andean and Middle American genotypes with superior levels of resistance to the eight races were identified. YBC278 was the only one among 255 genotypes that was highly resistant to all eight races. Resistance to anthracnose in the YBC was controlled by major-effect loci on chromosomes Pv01, Pv03, Pv04, Pv05 and Pv07. The genomic region on Pv01, which overlapped with the Andean locus Co-1 provided resistance to races 81, 1050 and 1105. Significant SNPs for resistance to race 39 were identified on Pv02. The genomic region on Pv04, which overlapped with known major-effect loci Co-3, Co-15, Co-16, Co-y and Co-z, provided resistance to races 5, 19, 51 and 183. Novel genomic regions for resistance to race 39 were identified on Pv05 and Pv07. Plant resistance genes (R genes) with NB-ARC and LRR domains, which occurred in clusters, were identified as positional candidate genes for genomic regions on Pv02 and Pv04.

Hepatoprotective Effect of Kaempferol: A Review of the Dietary Sources, Bioavailability, Mechanisms of Action, and Safety

The liver is the body's most critical organ that performs vital functions. Hepatic disorders can affect the physiological and biochemical functions of the body. Hepatic disorder is a condition that describes the damage to cells, tissues, structures, and functions of the liver, which can cause fibrosis and ultimately result in cirrhosis. These diseases include hepatitis, ALD, NAFLD, liver fibrosis, liver cirrhosis, hepatic failure, and HCC. Hepatic diseases are caused by cell membrane rupture, immune response, altered drug metabolism, accumulation of reactive oxygen species, lipid peroxidation, and cell death. Despite the breakthrough in modern medicine, there is no drug that is effective in stimulating the liver function, offering complete protection, and aiding liver cell regeneration. Furthermore, some drugs can create adverse side effects, and natural medicines are carefully selected as new therapeutic strategies for managing liver disease. Kaempferol is a polyphenol contained in many vegetables, fruits, and herbal remedies. We use it to manage various diseases such as diabetes, cardiovascular disorders, and cancers. Kaempferol is a potent antioxidant and has anti-inflammatory effects, which therefore possesses hepatoprotective properties. The previous research has studied the hepatoprotective effect of kaempferol in various hepatotoxicity protocols, including acetaminophen (APAP)-induced hepatotoxicity, ALD, NAFLD, CCl₄, HCC, and lipopolysaccharide (LPS)-induced acute liver injury. Therefore, this report aims to provide a recent brief overview of the literature concerning the hepatoprotective effect of kaempferol and its possible molecular mechanism of action. It also provides the most recent literature on kaempferol's chemical structure, natural source, bioavailability, and safety.

Antinutritional factors, nutritional improvement, and future food use of common beans: A perspective

Common bean seeds are an excellent source of protein as well as of carbohydrates, minerals, vitamins, and bioactive compounds reducing, when in the diet, the risks of diseases. The presence of bioactive compounds with antinutritional properties (e.g., phytic acid, lectins, raffinosaccharides, protease inhibitors) limits, however, the bean's nutritional value and its wider use in food preparations. In the last decades, concerted efforts have been, therefore, made to develop new common bean genotypes with reduced antinutritional compounds by exploiting the natural genetic variability of common bean and also applying induced mutagenesis. However, possible negative, or positive, pleiotropic effects due to these modifications, in terms of plant performance in response to stresses or in the resulting technological properties of the developed mutant genotypes, have yet not been thoroughly investigated. The purpose of the perspective paper is to first highlight the current advances, which have been already made in mutant bean characterization. A view will be further provided on future research directions to specifically explore further advantages and disadvantages of these bean mutants, their potential use in innovative foods and representing a valuable genetic reservoir of combinations to assess the true functional role of specific seed bioactive components directly in the food matrix.

The Common Bean V Gene Encodes Flavonoid 3'5' Hydroxylase: A Major Mutational Target for Flavonoid Diversity in Angiosperms

The classic V (violet, purple) gene of common bean (Phaseolus vulgaris) functions in a complex genetic network that controls seed coat and flower color and flavonoid content. V was cloned to understand its role in the network and the evolution of its orthologs in the Viridiplantae. V mapped genetically to a narrow interval on chromosome Pv06. A candidate gene was selected based on flavonoid analysis and confirmed by recombinational mapping. Protein and domain modeling determined V encodes flavonoid 3'5' hydroxylase (F3'5'H), a P450 enzyme required for the expression of dihydromyricetin-derived flavonoids in the flavonoid pathway. Eight recessive haplotypes, defined by mutations of key functional domains required for P450 activities, evolved independently in the two bean gene pools from a common ancestral gene. V homologs were identified in Viridiplantae orders by functional domain searches. A phylogenetic analysis determined F3'5'H first appeared in the Streptophyta and is present in only 41% of Angiosperm reference genomes. The evolutionarily related flavonoid pathway gene flavonoid 3' hydroxylase (F3'H) is found nearly universally in all Angiosperms. F3'H may be conserved because of its role in abiotic stress, while F3'5'H evolved as a major target gene for the evolution of flower and seed coat color in plants.

Seed coat color genetics and genotype × environment effects in yellow beans via machine-learning and genome-wide association

Common bean (Phaseolus vulgaris L.) is consumed worldwide, with strong regional preferences for seed appearance characteristics. Colors of the seed coat, hilum ring, and corona are all important, along with susceptibility to postharvest darkening, which decreases seed value. This study aimed to characterize a collection of 295 yellow bean genotypes for seed appearance and postharvest darkening, evaluate genotype × environment (G × E) effects and map those traits via genome-wide association analysis. Yellow bean germplasm were grown for 2 yr in Michigan and Nebraska and seed were evaluated for L*a*b* color values, postharvest darkening, and hilum ring and corona colors. A model to exclude the hilum ring and corona of the seeds, black background, and light reflection was developed by using machine learning, allowing for targeted and efficient L*a*b* value extraction from the seed coat. The G × E effects were significant for the color values, and Michigan-grown seeds were darker than Nebraska-grown seeds. Single-nucleotide polymorphisms (SNPs) were associated with L* and hilum ring color on Pv10 near the J gene involved in mature seed coat color and hilum ring color. A SNP on Pv07 associated with L*, a*, postharvest darkening, and hilum ring and corona colors was near the P gene, the ground factor gene for seed coat color expression. The machine-learning-aided model used to extract color values from the seed coat, the wide variability in seed morphology traits, and the associated SNPs provide tools for future breeding and research efforts to meet consumers' expectations for bean seed appearance.

Iron Bioavailability from Infant Cereals Containing Whole Grains and Pulses: A Stable Isotope Study in Malawian Children

BACKGROUND

Compared with infant cereals based on refined grains, an infant cereal containing whole grains (WGs) and pulses with adequate amounts of ascorbic acid to protect against absorption inhibitors could be a healthier source of well-absorbed iron. However, iron absorption from such cereals is uncertain.

OBJECTIVE

We measured iron bioavailability from ferrous fumarate (Fefum) added to commercial infant cereals containing 1) refined wheat flour (reference meal), 2) WG wheat and lentil flour (WG-wheat-lentil), 3) WG wheat and chickpea flour (WG-wheat-chickpeas), and 4) WG oat flour (WG-oat) and from ferrous bisglycinate (FeBG) added to the same oat-based cereal (WG-oat-FeBG).

METHODS

In a prospective, single-blinded randomized crossover study, 6- to 14-mo-old Malawian children (n = 30) consumed 25-g servings of all 5 test meals containing 2.25 mg stable isotope-labeled iron and 13.5 mg ascorbic acid. Fractional iron absorption (FIA) was assessed by erythrocyte incorporation of isotopes after 14 d. Comparisons were made using linear mixed models.

RESULTS

Seventy percent of the children were anemic and 67% were iron deficient. Geometric mean FIA percentages (-SD, +SD) from the cereals were as follows: 1) refined wheat, 12.1 (4.8, 30.6); 2) WG-wheat-lentil, 15.8 (6.6, 37.6); 3) WG-wheat-chickpeas, 12.8 (5.5, 29.8); and 4) WG-oat, 9.2 (3.9, 21.5) and 7.4 (2.9, 18.9) from WG-oat-FeBG. Meal predicted FIA (P ≤ 0.001), whereas in pairwise comparisons, only WG-oat-FeBG was significantly different compared with the refined wheat meal (P = 0.02). In addition, FIAs from WG-wheat-lentil and WG-wheat-chickpeas were significantly higher than from WG-oat (P = 0.002 and P = 0.04, respectively) and WG-oat-FeBG (P < 0.001 and P = 0.004, respectively).

CONCLUSION

In Malawian children, when given with ascorbic acid at a molar ratio of 2:1, iron bioavailability from Fefum-fortified infant cereals containing WG wheat and pulses is ≈13-15%, whereas that from FeBG- and Fefum-fortified infant cereals based on WG oats is ≈7-9%.

Iron Bioavailability from Multiple Biofortified Foods Using an In Vitro Digestion, Caco-2 Assay for Optimizing a Cyclical Menu for a Randomized Efficacy Trial

BACKGROUND

Inadequate nutritional status contributes to substantial losses in human health and productivity globally. A multiple biofortified food crop trial targeting iron, zinc, and vitamin A deficiencies among young children and their breastfeeding mothers is being conducted in India.

OBJECTIVE

We sought to determine the relative iron bioavailability from biofortified and conventional crops and crop combinations representative of a cyclical menu using crops targeted for inclusion in the feeding trial.

METHODS

Crops were procured from India, cooked, freeze-dried, and analyzed with an established in vitro digestion/Caco-2 iron bioavailability assay using a fixed sample weight. Crop proportions representative of meals planned for the human study were determined and combined such that samples included either all biofortified or all control crops. Crops were analyzed as single crops (n = 4) or crop combinations (n = 7) by variety (biofortified or control) in triplicate. The primary outcome was iron uptake measured by Caco-2 ferritin production normalized to total Caco-2 protein (nanograms of ferritin/milligrams of cell protein) analyzed for effects of crop variety and crop proportion using generalized linear models.

RESULTS

Biofortified pearl millet alone demonstrated higher iron uptake than conventional varieties (5.01 ± 1.66 vs. 2.17 ± 0.96; P = 0.036). Addition of sweet potato or sweet potato + pulse improved iron uptake for all proportions tested in control varieties and select proportions for biofortified varieties (P ≤ 0.05). Two multiple crop combinations demonstrated modestly higher iron uptake from biofortified crops.

CONCLUSIONS

Optimizing total iron delivery should consider matrix effects, processing, and promoters/inhibitors of iron absorption in addition to total iron concentration. Future directions include evaluating recipes as prepared for consumption and comparison against human iron bioavailability studies.

Elucidation of the low resistant starch phenotype in Phaseolus vulgaris exhibited in the yellow bean Cebo Cela

Dry beans(Phaseolus vulgaris) are rich in complex carbohydrates including resistant starch (RS). RS, the starch fraction that escapes digestion, typically ranges from 35% in raw beans to 4% in cooked beans. A low RS bean genotype, Cebo Cela, was identified with 96% less RS (1.5% RS) than normal raw beans. The goal of this research was to elucidate the factors responsible for this low RS phenotype. The low RS phenotype was evaluated in whole bean flour and starch in Cebo Cela (yellow), Canario (yellow), Alpena (navy) and Samurai (otebo). α-Amylase activation was found to be a major contributor of the low RS content phenotype of the whole bean flour for Cebo Cela (-21.9% inhibition). Total starch (43.6%-40.2%), amylose (31.0%-31.5%), molecular weight and chain length distributions of amylose and amylopectin did not contribute to the low RS phenotype. Yellow bean starches were digested nearly 1.5 times (95%-94%) faster than starch granules from otebo and navy beans (65%-73%) due to lower proportions of amylopectin chains. PRACTICAL APPLICATION: This study is of value to the food industry because the yellow bean, Cebo Cela, is easily hydrolyzed by α-amylase and also has α-amylase promotion properties. Therefore, Cebo Cela can be used as an alternate starch source for ethanol fermentation and for the production of maltodextrins and fructose/glucose syrups which are used as food thickeners and sweeteners.

Redefining Bean Iron Biofortification: A Review of the Evidence for Moving to a High Fe Bioavailability Approach

Iron biofortification of the common bean (Phaseolus vulgaris) commenced in earnest ~18 years ago. Based on knowledge at the time, the biofortification approach for beans was simply to breed for increased Fe concentration based on 3 major assumptions: (1) The average bean Fe concentration is ~50 μg/g; (2) Higher Fe concentration results in more bioavailable Fe delivered for absorption; (3) Breeding for high Fe concentration is a trait that can be achieved through traditional breeding and is sustainable once a high Fe bean sample is released to farmers. Current research indicates that the assumptions of the high Fe breeding approach are not met in countries of East Africa, a major focus area of bean Fe biofortification. Thus, there is a need to redefine bean Fe biofortification. For assumption 1, recent research indicates that the average bean Fe concentration in East Africa is 71 μg/g, thus about 20 μg/g higher than the assumed value. For assumption 2, recent studies demonstrate that for beans higher Fe concentration does not always equate to more Fe absorption. Finally, for assumption 3, studies show a strong environment and genotype by environment effect on Fe concentration, thus making it difficult to develop and sustain high Fe concentrations. This paper provides an examination of the available evidence related to the above assumptions, and offers an alternative approach utilizing tools that focus on Fe bioavailability to redefine Fe biofortification of the common bean.

Role of Flavonoids in the Treatment of Iron Overload

Iron overload, a high risk factor for many diseases, is seen in almost all human chronic and common diseases. Iron chelating agents are often used for treatment but, at present, most of these have a narrow scope of application, obvious side effects, and other disadvantages. Recent studies have shown that flavonoids can affect iron status, reduce iron deposition, and inhibit the lipid peroxidation process caused by iron overload. Therefore, flavonoids with iron chelating and antioxidant activities may become potential complementary therapies. In this study, we not only reviewed the research progress of iron overload and the regulation mechanism of flavonoids, but also studied the structural basis and potential mechanism of their function. In addition, the advantages and disadvantages of flavonoids as plant iron chelating agents are discussed to provide a foundation for the prevention and treatment of iron homeostasis disorders using flavonoids.

Investigation of Genotype by Environment Interactions for Seed Zinc and Iron Concentration and Iron Bioavailability in Common Bean

Iron and zinc malnutrition are global public health concerns afflicting mostly infants, children, and women in low- and middle-income countries with widespread consumption of plant-based diets. Common bean is a widely consumed staple crop around the world and is an excellent source of protein, fiber, and minerals including iron and zinc. The development of nutrient-dense common bean varieties that deliver more bioavailable iron and zinc with a high level of trait stability requires a measurement of the contributions from genotype, environment, and genotype by environment interactions. In this research, we investigated the magnitude of genotype by environment interaction for seed zinc and iron concentration and seed iron bioavailability (FeBIO) using a set of nine test genotypes and three farmers' local check varieties. The research germplasm was evaluated for two field seasons across nine on-farm locations in three agro-ecological zones in Uganda. Seed zinc concentration ranged from 18.0 to 42.0 μg g^-1 and was largely controlled by genotype, location, and the interaction between location and season [28.0, 26.2, and 14.7% of phenotypic variability explained (PVE), respectively]. Within a genotype, zinc concentration ranged on average 12 μg g^-1 across environments. Seed iron concentration varied from 40.7 to 96.7 μg g^-1 and was largely controlled by genotype, location, and the interaction between genotype, location, and season (25.7, 17.4, and 13.7% of PVE, respectively). Within a genotype, iron concentration ranged on average 28 μg g^-1 across environments. Seed FeBIO ranged from 8 to 116% of Merlin navy control and was largely controlled by genotype (68.3% of PVE). The red mottled genotypes (Rozi Koko and Chijar) accumulated the most seed zinc and iron concentration, while the yellow (Ervilha and Cebo Cela) and white (Blanco Fanesquero) genotypes had the highest seed FeBIO and performed better than the three farmers' local check genotypes (NABE-4, NABE-15, and Masindi yellow). The genotypes with superior and stable trait performance, especially the Manteca seed class which combine high iron and zinc concentrations with high FeBIO, would serve as valuable parental materials for crop improvement breeding programs aimed at enhancing the nutritional value of the common bean.

Opportunities for plant-derived enhancers for iron, zinc, and calcium bioavailability: A review

Understanding of the mechanism of interactions between dietary elements, their salts, and complexing/binding ligands is vital to manage both deficiency and toxicity associated with essential element bioavailability. Numerous mineral ligands are found in both animal and plant foods and are known to exert bioactivity via element chelation resulting in modulation of antioxidant capacity or micobiome metabolism among other physiological outcomes. However, little is explored in the context of dietary mineral ligands and element bioavailability enhancement, particularly with respect to ligands from plant-derived food sources. This review highlights a novel perspective to consider various plant macro/micronutrients as prospective bioavailability enhancing ligands of three essential elements (Fe, Zn, and Ca). We also delineate the molecular mechanisms of the ligand-binding interactions underlying mineral bioaccessibility at the luminal level. We conclude that despite current understandings of some of the structure-activity relationships associated with strong mineral-ligand binding, the physiological links between ligands as element carriers and uptake at targeted sites throughout the gastrointestinal (GI) tract still require more research. The binding behavior of potential ligands in the human diet should be further elucidated and validated using pharmacokinetic approaches and GI models.

Iron Concentrations in Biofortified Beans and Nonbiofortified Marketplace Varieties in East Africa Are Similar

BACKGROUND

The predominant bean iron (Fe) biofortification approach is to breed for high Fe concentration and assumes the average Fe concentration is 50 μg/g. This approach also assumes that a 40 μg/g increase is sustainable and Fe bioavailability will not decrease to negate the increase in Fe.

OBJECTIVE

The overall objective was to determine if bean Fe biofortification via breeding for high Fe is producing beans with higher Fe concentration relative to nonbiofortified lines found in the East Africa marketplace.

METHODS

Seventy-six marketplace samples (East Africa Marketplace Collection; EAMC), and 154 genotypes known to be representative of the marketplace were collected from breeders in the Pan-Africa Bean Research Alliance (designated the East Africa Breeder Collection; EABC). Within the EAMC and EABC were 18 and 35 samples, respectively, that were released as biofortified lines. All samples were measured for Fe concentration. The Caco-2 cell bioassay assessed Fe bioavailability of the EAMC. Biofortified versus nonbiofortified samples were compared by the appropriate t-test or ANOVA.

RESULTS

The Fe concentration of the 58 nonbiofortified EAMC lines was (mean ± SD [range]) 71 ± 9 μg/g (52-93 μg/g) which did not differ significantly from the 18 biofortified EAMC varieties (71 ± 11 μg/g [55-94 μg/g]). The Fe concentration of the 119 nonbiofortified EABC varieties was 66 ± 7 μg/g (51-90 μg/g) which was significantly different (P < 0.0001) from the 35 EABC biofortified lines (73 ± 9 μg/g [60-91 μg/g]). However, the EABC biofortified lines were not different from the nonbiofortified EAMC samples. In the Caco-2 cell bioassay, biofortified EAMC varieties did not deliver more Fe compared with nonbiofortified EAMC varieties.

CONCLUSIONS

The assumptions of the high Fe bean biofortification approach are not met in the East African marketplace. Iron concentration and bioavailability measurement indicate the biofortified bean varieties are providing no additional dietary Fe.