Phytochemical distribution in hull and cotyledon of adzuki bean (Vigna angularis L.) and mung bean (Vigna radiate L.), and their contribution to antioxidant, anti-inflammatory and anti-diabetic activities

Effects of different adzuki bean flour additions on structural and functional characteristics of extruded buckwheat noodles

BACKGROUND

Understanding the effects of different additions of adzuki bean flour (ABF) on structural and functional characteristics of extruded buckwheat noodles is important in developing high-quality starchy foods with desirable glycemic indexes. This study explored how varying amounts of ABF in extruded buckwheat noodles influenced their structural and functional characteristics.

RESULTS

The findings indicated that adding ABF substantially boosted the levels of protein and flavonoids, while decreasing the content of fat and starch. Adding ABF to the noodles extended the optimum cooking time and led to a reduction in both the stickiness of the cooked noodles and the pore size of the starch gel structure, compared with pure buckwheat noodles. Fourier transform infrared spectroscopy indicated that R1047/1022 increased with the content of ABF increased, while R1022/995 decreased. X-ray diffraction showed that the relative crystallinity of buckwheat noodles was enhanced with increasing ABF amount. Adding ABF notably significantly decreased the estimated glycemic index. The buckwheat noodles extruded with 20% ABF addition demonstrated notably stronger α-glucosidase inhibitory effects than those extruded with no ABF addition.

CONCLUSION

The present study demonstrates that the additions of ABF improved the structure and hypoglycemic activity of extruded buckwheat noodles while decreasing starch digestibility, and the optimal value was reached at an ABF addition of 20%. The study might fill gaps in starch noodle research and provide a new strategy for the development of functional food in the food industry. © 2024 Society of Chemical Industry.

The Effects of Single- or Mixed-Strain Fermentation of Red Bean Sourdough, with or without Wheat Bran, on Bread Making Performance and Its Potential Health Benefits in Mice Model

The effects of single- (Lactobacillus fermentum) or mixed-strain (Lactobacillus fermentum, Kluyveromyces marxianus) fermentation of red bean with or without wheat bran on sourdough bread quality and nutritional aspects were investigated. The results showed that, compared to unfermented controls, the tannins, phytic acid, and trypsin inhibitor levels were significantly reduced, whereas the phytochemical (TPC, TFC, and gallic acid) and soluble dietary fiber were increased in sourdough. Meanwhile, more outstanding changes were obtained in sourdough following a mixed-strain than single-strain fermentation, which might be associated with its corresponding β-glucosidase, feruloyl esterase, and phytase activities. An increased specific volume, reduced crumb firmness, and greater sensory evaluation of bread was achieved after mixed-strain fermentation. Moreover, diets containing sourdough, especially those prepared with mixed-strain-fermented red bean with wheat bran, significantly decreased serum pro-inflammatory cytokines levels, and improved the lipid profile, HDL/LDL ratio, glucose tolerance, and insulin sensitivity of mice. Moreover, gut microbiota diversity increased towards beneficial genera (e.g., Bifidobacterium), accompanied with a greater increase in short-chain fatty acid production in mice fed on sourdough-based bread diets compared to their controls and white bread. In conclusion, mixed-strain fermentation's synergistic effect on high fiber-legume substrate improved the baking, sensory quality, and prebiotic effect of bread, leading to potential health benefits in mice.

Effects of Purified Vitexin and Iso-Vitexin from Mung Bean Seed Coat on Antihyperglycemic Activity and Gut Microbiota in Overweight Individuals' Modulation

Exceeding a healthy weight significantly elevates the likelihood of developing type 2 diabetes (T2DM). A commercially available singular constituent, available as either purified vitexin or iso-vitexin, has been associated with a decreased risk of T2DM, but its synergistic effect has not been reported yet. Vitexin and iso-vitexin were extracted using an ethanol-based solvent from mung bean seed coat (MBCE) and subsequently purified using preparative liquid chromatography (Prep-LC). Eleven mixture ratios of vitexin and/or iso-vitexin were determined for their antioxidant and antihyperglycemic activities. The 1:1.5 ratio of vitexin to iso-vitexin from MBCE demonstrated the most synergistic effects for enzyme inhibition and glucose uptake in HepG2 cells within an insulin-resistant system, while these ratios exhibited a significantly lower antioxidant capacity than that of each individual component. In a gut model system, the ratio of 1:1.5 (vitexin and iso-vitexin) regulated the gut microbiota composition in overweight individuals by decreasing the growth of Enterobacteriaceae and Enterococcaceae, while increasing in Ruminococcaceae and Lachnospiraceae. The application of vitexin/iso-vitexin for 24 h fermentation enhanced a high variety of abundances of 21 genera resulting in five genera of Parabacteroides, Ruminococcus, Roseburia, Enterocloster, and Peptacetobacter, which belonged to the phylum Firmicutes, exhibiting high abundant changes of more than 5%. Only two genera of Proteus and Butyricicoccus belonging to Proteobacteria and Firmicutes decreased. The findings suggest that these phytochemicals interactions could have synergistic effects in regulating glycemia, through changes in antihyperglycemic activity and in the gut microbiota in overweight individuals. This optimal ratio can be utilized by industries to formulate more potent functional ingredients for functional foods and to create nutraceutical supplements aimed at reducing the risk of T2DM in overweight individuals.

Extractions, Contents, Antioxidant Activities and Compositions of Free and Bound Phenols from Kidney Bean Seeds Represented by 'Yikeshu' Cultivar in Cold Region

To thoroughly understand the profile of phenolic phytochemicals in kidney bean seeds cultivated in a cold region, the extractions, contents, antioxidant activities, compositions of free and bound phenols in the seed coat and cotyledon, and also relevant color attributes, were investigated. The results indicated that ultrasound-assisted extraction was an efficient method for free phenols. The bound phenols in seed coat and cotyledon were released more efficiently by alkali-acid and acid-alkali sequential hydrolysis, respectively. Under the optimized extractions, total phenols (TPC), flavonoids (TFC), and anthocyanins (TAC) ranged in 7.81-32.89 mg GAE/g dw, 3.23-15.65 mg RE/g dw, and 0-0.21 mg CE/g dw in the whole seeds of the five common kidney beans. There was a big difference in phenolic distribution between red and white seeds. From whole seed, the phenols in the four red cultivars mainly existed in free state (78.84%) and seed coat (71.56%), while the phenols in the white 'Sark' divided equally between free (51.18%) and bound (48.82%) states and consisted chiefly in cotyledon (81.58%). The correlation analyses showed that the antioxidant activities were significantly and positively correlated with TPC and TFC. The phenolic attributes were closely associated with the color of the seed coat. Red seeds had higher total contents of phenols than white seeds. TAC had a positively significant correlation with redness. Brightness and yellowness showed a negatively significant correlation with TPC, TFC, and antioxidant capacities, which were necessarily linked with redness degree and spot in red seeds. The spotted red 'Yikeshu' with the most outstanding performance on phenolic attributes was selected to analyze phenolic compounds with UHPLC-QE-MS. Among the 85 identified phenolics, 2 phenolic acids and 10 flavonoids were dominant. The characteristic phenolics in free and bound states were screened in both seed coat and cotyledon, respectively. The available information on the phenolic profile may expand the utilization of kidney beans as a nutritional ingredient in the food industry.

Potential anti-obesity effect of saponin metabolites from adzuki beans: A computational approach

In contrast to its widespread traditional and popular culinary use to reduce weight, Vigna angularis (adzuki beans) was not subjected to sufficient scientific scrutiny. Particularly, its saponins whose role was never investigated before to unveil the beans' antidiabetic and anti-obesity effects. Four vital pancreatic and intestinal carbohydrate enzymes were selected to assess the potency of the triterpenoidal saponins of V. angularis to bind and activate these proteins through high-precision molecular modeling and dynamics mechanisms with accurate molecular mechanics Generalized Born Surface Area (MMGBSA) energy calculations; thus, recognizing their anti-obesity potential. Our results showed that adzukisaponin VI and adzukisaponin IV were the best compounds in the α-amylase and α-glucosidase enzymatic grooves, respectively. Adzukisaponin VI and angulasaponin C were the best fitting in the N-termini of sucrase-isomaltose (SI) enzyme, and angulasaponin C was the best scoring compound in maltase-glucoamylase C-termini. All of them outperformed the standard drug acarbose. These compounds in their protein complexes were selected to undergo molecular simulations of the drug-bound protein compared to the apo-protein through 100 ns, which confirmed the consistency of binding to the key amino acid residues in the four enzyme pockets with the least propensity of unfolding. Detailed analysis is given of the different polar and hydrophobic binding interactions of docked compounds. While maltase-adzukisaponin VI complex scored the lowest MMGBSA free energy of -67.77 Kcal/mol, α-amylase complex with angulasaponin B revealed the free binding energy of -74.18 Kcal/mol with a dominance of van der Waals energy (ΔEVDW) and the least change from the start to the end of the simulation time. This study will direct researchers to the significance of isolating the pure adzuki saponin components to conduct future in vitro and in vivo experimental works and even clinical trials.

Chemical derivatization strategies for enhancing the HPLC analytical performance of natural active triterpenoids

Triterpenoids widely exist in nature, displaying a variety of pharmacological activities. Determining triterpenoids in different matrices, especially in biological samples holds great significance. High-performance liquid chromatography (HPLC) has become the predominant method for triterpenoids analysis due to its exceptional analytical performance. However, due to the structural similarities among botanical samples, achieving effective separation of each triterpenoid proves challenging, necessitating significant improvements in analytical methods. Additionally, triterpenoids are characterized by a lack of ultraviolet (UV) absorption groups and chromophores, along with low ionization efficiency in mass spectrometry. Consequently, routine HPLC analysis suffers from poor sensitivity. Chemical derivatization emerges as an indispensable technique in HPLC analysis to enhance its performance. Considering the structural characteristics of triterpenoids, various derivatization reagents such as acid chlorides, rhodamines, isocyanates, sulfonic esters, and amines have been employed for the derivatization analysis of triterpenoids. This review comprehensively summarized the research progress made in derivatization strategies for HPLC detection of triterpenoids. Moreover, the limitations and challenges encountered in previous studies are discussed, and future research directions are proposed to develop more effective derivatization methods.

Deep Eutectic Solvents as New Extraction Media for Flavonoids in Mung Bean

Mung beans contain abundant flavonoids like vitexin and isovitexin, which contribute to their strong bioactivities, such as antioxidant effects, so efforts should focus on extracting bioactive flavonoids as well as aligning with the goal of green extraction for specific applications. Deep eutectic solvent coupled with ultrasound-assisted extraction (DES-UAE) was applied to extract flavonoids from mung beans, and eight different DESs were compared on the extraction yield. In addition, the traditional extraction method with 30% ethanol was performed as the reference. The results showed that ethylene glycol-glycolic acid achieved the highest yield among all the DESs, 1.6 times that of the reference values. Furthermore, the DES-UAE parameters were optimized as a 60 mL/g liquid-solid ratio, 30% water content in DES, 200 W ultrasonic power, 67 °C ultrasonic temperature, and 10 min extraction time, leading to the DES extract with the maximum extraction yield of 2339.45 ± 42.98 μg/g, and the significantly stronger DPPH and ABTS radical scavenging ability than the traditional extract. Therefore, employing DES and ultrasonic extraction together offers a green method for extracting flavonoids from mung beans, advancing the development and utilization of plant-derived effective components in a sustainable manner.

Gut Microbiota Plays Essential Roles in Soyasaponin's Preventive Bioactivities against Steatohepatitis in the Methionine and Choline Deficient (MCD) Diet-Induced Non-Alcoholic Steatohepatitis (NASH) Mice

SCOPE

Gut microbiota (GM) is involved in nonalcoholic steatohepatitis (NASH) development. Phytochemicals soyasaponins can prevent NASH possibly by modulating GM. This study aims to investigate the preventive bioactivities of soyasaponin monomers (SS-A1 and SS-Bb) against NASH and explores the mechanisms by targeting GM.

METHODS AND RESULTS

Male C57BL/6 mice are fed with methionine and choline deficient (MCD) diet containing SS-A1 , SS-Bb, or not for 16 weeks. Antibiotics-treated pseudo germ-free (PGF) mice are fed with MCD diet containing SS-A1 , SS-Bb, or not for 8 weeks. GM is determined by 16S rRNA amplicon sequencing. Bile acids (BAs) are measured by UPLC-MS/MS. In NASH mice, SS-A1 and SS-Bb alleviate steatohepatitis and fibrosis, reduce ALT, AST, and LPS in serum, decrease TNF-α, IL-6, α-SMA, triglycerides, and cholesterol in liver. SS-A1 and SS-Bb decrease Firmicutes, Erysipelotrichaceae, unidentified-Clostridiales, Eggerthellaceae, Atopobiaceae, Aerococcus, Jeotgalicoccus, Gemella, Rikenella, increase Proteobacteria, Verrucomicrobia, Akkermansiaceae, Romboutsia, and Roseburia. SS-A1 and SS-Bb alter BAs composition in liver, serum, and feces, activate farnesoid X receptor (FXR) in liver and ileum, increase occludin and ZO-1 in intestine. However, GM clearance abrogates the preventive bioactivities of SS-A1 and SS-Bb against NASH.

CONCLUSION

GM plays essential roles in soyasaponin's preventive bioactivities against steatohepatitis in MCD diet-induced NASH mice.

Mung bean as a potent emerging functional food having anticancer therapeutic potential: Mechanistic insight and recent updates

Cancer is still a major challenge for humans. In recent years, researchers have focused on plant-based metabolites as a safe, efficient, alternative or combinatorial, as well as cost-effective preventive strategy against carcinogenesis. Mung bean is an important nutritious legume, and known for providing various health benefits due to various bioactive phytochemicals and easily digestible proteins. Regular intake of mung bean helps to regulate metabolism by affecting the growth and survival of good microbes in the host gut. Mung bean has also been reported to have anti-inflammatory, antioxidant, antiproliferative, and immunomodulatory properties. These properties may possess the preventive potential of mung bean against carcinogenesis. Bibliographic databases for peer-reviewed research literature were searched through a structured conceptual approach using focused review questions on mung beans, anticancer, therapeutics, and functional foods along with inclusion/exclusion criteria. For the appraisal of the quality of retrieved articles, standard tools were employed. A deductive qualitative content analysis methodology further led us to analyze outcomes of the research and review articles. The present review provides recent updates on the anticancer potential of mung bean and the possible mechanism of action thereof to prevent carcinogenesis and metastasis. Extensive research on the active metabolites and mechanisms of action is required to establish the anticancer potential of mung bean. Keeping the above facts in view, mung bean should be investigated for its bioactive compounds, to be considered as functional food of the future.

The Effect of Illumination Patterns during Mung Bean Seed Germination on the Metabolite Composition of the Sprouts

Mung bean (Vigna radiata (L.) Wilczek) sprouts are popular over the world because of their taste, nutritional value, well-balanced biochemical composition, and other properties beneficial for human health. Germination conditions affect the composition of metabolites in mung bean sprouts, so a detailed study into its variability is required. This article presents the results of a comparison of the metabolite composition in the leaves of mung bean sprouts germinated first in the dark (DS) and then in the light (LS). Gas chromatography with mass spectrometry (GC-MS) made it possible to identify more than 100 compounds representing various groups of phytochemicals. Alcohols, amino acids, and saccharides predominated in the total amount of compounds. The analysis of metabolomic profiles exposed a fairly high intra- and intervarietal variability in the metabolite content. DS and LS differed in the qualitative and quantitative content of the identified compounds. The intravarietal variability was more pronounced in DS than in LS. DS demonstrated higher levels of saccharides, fatty acids, acylglycerols, and phenolic compounds, while amino acids were higher in LS. Changes were recorded in the quantitative content of metabolites participating in the response of plants to stressors-ornithine, proline, GABA, inositol derivatives, etc. The changes were probably induced by the stress experienced by the sprouts when they were transferred from shade to light. The analysis of variance and principal factor analysis showed the statistically significant effect of germination conditions on the content of individual compounds in leaves. The identified features of metabolite variability in mung bean genotypes grown under different conditions will contribute to more accurate selection of an illumination pattern to obtain sprouts with desirable biochemical compositions for use in various diets and products with high nutritional value.

Integration of comparative transcriptomics and WGCNA characterizes the regulation of anthocyanin biosynthesis in mung bean (Vigna radiata L.)

Mung bean is a dual-use crop widely cultivated in Southeast Asia as a food and medicine resource. The development of new functional mung bean varieties demands identifying new genes regulating anthocyanidin synthesis and investigating their molecular mechanism. In this study, we used high-throughput sequencing technology to generate transcriptome sequence of leaves, petioles, and hypocotyls for investigating the anthocyanins accumulation in common mung bean variety as well as anthocyanidin rich mung bean variety, and to elucidate their molecular mechanisms. 29 kinds of anthocyanin compounds were identified. Most of the anthocyanin components contents were significantly higher in ZL23 compare with AL12. Transcriptome analysis suggested that a total of 93 structural genes encoding the anthocyanin biosynthetic pathway and 273 regulatory genes encoding the ternary complex of MYB-bHLH-WD40 were identified, of which 26 and 78 were differentially expressed in the two varieties. Weighted gene co-expression network analysis revealed that VrMYB3 and VrMYB90 might have enhanced mung bean anthocyanin content by inducing the expression of structural genes such as PAL, 4CL, F3'5'H, LDOX, and F3'H, which was consistent with qRT-PCR results. These findings are envisaged to provide a reference for studying the molecular mechanism of anthocyanin accumulation in mung beans.

Fermentation improves flavors, bioactive substances, and antioxidant capacity of Bian-Que Triple-Bean Soup by lactic acid bacteria

The ancient traditional Chinese drink Bian-Que Triple-Bean Soup made by fermentation (FTBS) of Lactococcus lactis subsp. lactis YM313 and Lacticaseibacillus casei YQ336 is a potential functional drink. The effect of fermentation on the flavor and biological activity of FTBS was evaluated by analyzing its chemical composition. Five volatile flavors were detected in modified FTBS. Fermentation decreased the proportion of nonanal (beany flavor substances) but significantly increased the total flavone contents, phenol contents and many bioactive small molecule substances in FTBS. The changes of these substances led to the significant improvement of FTBS sensory evaluation, antioxidant activity and prebiotic potential. This research provides a theoretical basis for the application of Lactic acid bacteria (LAB) in the fermentation of edible plant-based foods and transformation from traditional food to industrial production.

In vitro and in vivo Inhibitory Activity of C-glycoside Flavonoid Extracts from Mung Bean Coat on Pancreatic Lipase and α-glucosidase

Mung bean is a kind of legume commonly eaten by human. In the present study, a HPLC method for analyzing of two C-glycoside flavonoids, isovitexin and vitexin, in Mung bean was developed. Results showed that the flavonoids are mainly existed in Mung bean coat (MBC), while kernel contains very trace. The extraction of C-glycoside flavonoids from MBC was optimized. MBC extracts with isovitexin and vitexin contents of 29.0 ± 0.28% and 35.8 ± 0.19% were obtained with yield of 1.6 ± 0.21%. MBC extracts exhibited inhibitory activities on pancreatic lipase and α-glucosidase with IC50 values of 0.147 mg/ml and 0.226 mg/ml, respectively. The inhibitory kinetics revealed that MBC extracts showed mixed-type inhibition on these enzymes. Fluorescence quenching titration confirmed the binding of MBC extracts with the enzyme proteins. In vivo study revealed that pre-administration with MBC extracts significantly reduced the triglyceride absorption. Furthermore, it also improved postprandial hyperglycemia in rats through the inhibition of α-glucosidase.

Comprehensive compositional assessment of bioactive compounds in diverse pea accessions

Pea (Pisum sativum L.) is an important legume crop providing a good source of protein, vitamins, minerals and bioactive compounds with health benefits for humans. In this study, an improved method for simultaneous analysis of multiple phytoestrogens among 100 pea accessions was developed. Ipriflavone, (a synthetic isoflavone), was used as an internal standard for the semiquantitative analysis of 17 phytoestrogens including isoflavone aglycones and conjugates, allowing direct analysis of isoflavones in their naturally occurring forms. This comprehensive dataset demonstrated that the isoflavones varied greatly and some accessions tended to have high levels of multiple phytoestrogens among the 100 accessions analyzed. Isoliquiritigenin followed by glycitein were the predominant compounds detected in the accessions and showed the highest correlation with the total phytoestrogens content. Secoisolariciresinol content was consistently higher in yellow cotyledon peas than in green cotyledon peas, whereas the contents of coumestrol, genestein and secoisolariciresinol were significantly correlated with seed coat color. The total phenolics and saponins showed a wide range of variability among the accessions with higher concentrations of total phenolics observed in seeds with pigmented seed coat or yellow cotyledon seeds, suggesting the synthesis of saponins and phenolics are significantly affected by metabolic pathway genes controlling cotyledon color or seed coat color. This study profiled the variability of bioactive compounds of pea seed quality traits in diverse pea accessions and provides an immense resource for continued research, breeding and selection of genotypes for a wide range of applications.

Nutrient transfer and antioxidant effect of adzuki bean before and after GABA enrichment

In order to study the nutritional changes of γ-aminobutyric acid (GABA) enrichment in adzuki bean germination, vacuum combined with monosodium glutamate (MSG) was used as the germination stress of adzuki bean. The nutrient transfer before and after GABA enrichment in adzuki bean germination under vacuum combined with MSG stress were studied by means of chromatography and scanning electron microscope (SEM). The antioxidant activity and hypoglycemic effect of different solvent extracts before and after germination of adzuki bean were evaluated by experiments in vitro. The results showed that the nutritional characteristics of adzuki bean rich in GABA changed significantly (P < 0.05), the total fatty acids decreased significantly (P < 0.05), and the 21 amino acids detected increased significantly. After germination, the starch granules of adzuki bean became smaller and the surface was rough Germination stress significantly increased the antioxidant and hypoglycemic activities of the extracts from different solvents (P < 0.05), and the water extracts had the best effect on DPPH and ⋅OH radical scavenging rates of 88.52 and 83.56%, respectively. The results indicated that the germinated adzuki bean rich in GABA was more nutritious than the raw adzuki bean and had good antioxidant activity. It hoped to provide technical reference for rich food containing GABA.

Transcriptomic and biochemical analyses of drought response mechanism in mung bean (Vignaradiata (L.) Wilczek) leaves

Drought is a major factor that limiting mung bean development. To clarify the molecular mechanism of mung bean in response to drought stress, 2 mung bean groups were established, the experimental group (drought-treated) and the control group (normal water management). With prominent difference of 2 groups in stomatal conductance, relative water content and phenotype, leaf samples were collected at 4 stages, and the physiological index of MDA, POD, chlorophyll, and soluble proteins were estimated. RNA-seq was used to obtain high quality data of samples, and differentially expressed genes were identified by DESeq2. With GO and KEGG analysis, DEGs were enriched into different classifications and pathways. WGCNA was used to detect the relationship between physiological traits and genes, and qPCR was performed to confirm the accuracy of the data. We obtained 169.49 Gb of clean data from 24 samples, and the Q30 of each date all exceeded 94%. In total, 8963 DEGs were identified at 4 stages between the control and treated samples, and the DEGs were involved in most biological processes. 1270 TFs screened from DEGs were clustered into 158 TF families, such as AP2, RLK-Pelle-DLSVA, and NAC TF families. Genes related to physiological traits were closely related to plant hormone signaling, carotenoid biosynthesis, chlorophyll metabolism, and protein processing. This paper provides a large amount of data for drought research in mung bean.

Effect of enrichment of rice snacks with pulse seed coats on phenolic compound content, product features and consumer hedonic response

This study investigated the impact of seed coats from peas (PC) and chickpeas (CC) (at 15 % and 30 % levels) on rice-based co-extruded snacks. Using PC and CC reduced the content of soluble (29 %) and cell-wall bound phenolic acids (21 %), but it enhanced the amount and the profile of flavonoids of rice-based snacks (up to 16 times with PC), resulting in significantly higher antioxidant activity (134 %). Snacks with 15 % CC showed a higher section area (about 335 versus 191 mm2) and a lower average pore radius (20.1 versus 23.9 mm) than PC-snacks; however, such features did not affect either texture or porosity. At 30 % level, PC resulted in a more porous structure (porosity: 73.1 versus 66.7 %) with smaller pores (17.2 versus 27.3 mm) and high firmness (55.9 versus 40.1 N). Consumers' acceptability evaluation revealed that samples containing pulse seed coat were comparable and preferred to the control (i.e., 100 % polished rice).

Nutritional, functional, and bioactive properties of african underutilized legumes

Globally, legumes are vital constituents of diet and perform critical roles in maintaining well-being owing to the dense nutritional contents and functional properties of their seeds. While much emphasis has been placed on the major grain legumes over the years, the neglected and underutilized legumes (NULs) are gaining significant recognition as probable crops to alleviate malnutrition and give a boost to food security in Africa. Consumption of these underutilized legumes has been associated with several health-promoting benefits and can be utilized as functional foods due to their rich dietary fibers, vitamins, polyunsaturated fatty acids (PUFAs), proteins/essential amino acids, micro-nutrients, and bioactive compounds. Despite the plethora of nutritional benefits, the underutilized legumes have not received much research attention compared to common mainstream grain legumes, thus hindering their adoption and utilization. Consequently, research efforts geared toward improvement, utilization, and incorporation into mainstream agriculture in Africa are more convincing than ever. This work reviews some selected NULs of Africa (Adzuki beans (Vigna angularis), African yam bean (Sphenostylis stenocarpa), Bambara groundnut (Vigna subterranea), Jack bean (Canavalia ensiformis), Kidney bean (Phaseolus vulgaris), Lima bean (Phaseolus lunatus), Marama bean (Tylosema esculentum), Mung bean, (Vigna radiata), Rice bean (Vigna Umbellata), and Winged bean (Psophocarpus tetragonolobus)), and their nutritional, and functional properties. Furthermore, we highlight the prospects and current challenges associated with the utilization of the NULs and discusses the strategies to facilitate their exploitation as not only sources of vital nutrients, but also their integration for the development of cheap and accessible functional foods.

Mung Bean (Vigna radiata (L.) R. Wilczek) from Burkina Faso Used as Antidiabetic, Antioxidant and Antimicrobial Agent

Chronic non-communicable diseases are becoming more and more recurrent and require the addition of functional foods in our eating habits. Legumes due to their composition in biomolecules could meet this need. Much used in Chinese medicine, the mung bean arouses interest in Burkina Faso. The objective of this study is to perform phytochemical profiling and to evaluate certain biological properties of the mung bean in its natural or germinated state. Qualitative phytochemical screening was carried out by precipitation and differential staining tests. The antimicrobial activity was tested on in vitro growth by the agar medium diffusion method. DPPH and FRAP methods were used to assess antioxidant activity. The antidiabetic activity of hydroethanolic extracts was evaluated on rats rendered diabetic by streptozotocin, with metformin as a reference molecule. Phytochemistry has revealed the presence of phenolic compounds and derivatives in the mung bean, whether in its natural state (MBN) or in its germinated state (MBG). Only the MBG exhibits antimicrobial activity on 70% of the strains used. It appears that the MBG has a reducing power of the DPPH radical with an IC₅₀ of 28 mg/mL compared to the same extract of the MBN, which had an IC₅₀ of 32.5 mg/mL with a difference (p < 0.05) between the extracts. MBN extracts at a dose of 300 milligrams per kilogram of body weight (mg/kg.bw) showed a reduction (p < 0.0001) in glycaemia and kept the body weight of the animals constant throughout the treatment. In addition, the MBN regulated the level of total cholesterol, tryglicerides of LDL, ASAT, ALAT, urea and creatine. These results show that the mung bean grown in Burkina Faso is a health food, which, integrated into dietary habits, could contribute to the prevention of chronic diseases.

In Vitro Gastrointestinal Bioaccessibility, Bioactivities and Colonic Fermentation of Phenolic Compounds in Different Vigna Beans

Beans are widely consumed throughout the world, rich in non-nutrient phenolic compounds and other bioactive constituents, including alkaloids, lectins, and others. However, research about in vitro digestion impacts on the changes of bioactive compounds' release and related antioxidant potential in different Vigna beans is limited. This research aimed to assess the modifications that occur in the content and bioaccessibility of phenolic compounds in four Vigna samples (adzuki bean, black urid whole, black eye bean, and mung bean), their antioxidant properties, and short chain fatty acids (SCFAs) production through static in vitro gastrointestinal digestion and colonic fermentation. Adzuki bean exhibited relatively higher total phenolic content (TPC; 4.76 mg GAE/g) and antioxidant activities after in vitro digestion. The black eye beans' total flavonoid content (0.74 mg QE/g) and total condensed tannins (10.43 mg CE/g) displayed higher tendencies. For colonic fermentation, the greatest TPC value of entire samples was detected through a 2-h reaction. In most selected beans, phenolic compounds were comparably more bioaccessible during the oral phase. Acetic acid showed the highest level through SCFAs production, and the total SCFAs in adzuki beans was the greatest (0.021 mmol/L) after 16-h fermentation. Adzuki beans may be more beneficial to gut health and possess a stronger antioxidant potential after consumption.

Microwave-Assisted Extraction of Bioactive Compounds from Lentil Wastes: Antioxidant Activity Evaluation and Metabolomic Characterization

The recovery of industrial by-products is part of the zero-waste circular economy. Lentil seed coats are generally considered to be a waste by-product. However, this low-value by-product is rich in bioactive compounds and may be considered an eco-friendly source of health-promoting phytochemicals. For the first time, a sustainable microwave-assisted extraction technique was applied, and a solvent screening was carried out to enhance the bioactive compound content and the antioxidant activity of green and red lentil hull extracts. With respect to green lentil hull extracts that were obtained with different solvents, the aqueous extract of the red lentil seed coats showed the highest total phenolic and total flavonoid content (TPC = 28.3 ± 0.1 mg GAE/g dry weight, TFC = 1.89 ± 0.01 mg CE/100 mg dry weight, respectively), as well as the highest antioxidant activity, both in terms of the free radical scavenging activity (ABTS, 39.06 ± 0.73 mg TE/g dry weight; DPPH, IC50 = 0.39 μg/mL) and the protection of the neuroblastoma cell line (SH-SY5Y, IC50 = 10.1 ± 0.6 μg/mL), the latter of which has never been investigated so far. Furthermore, a metabolite discovery analysis was for the first time performed on the aqueous extracts of both cultivars using an HPLC separation which was coupled with an Orbitrap-based high-Resolution Mass Spectrometry technique.

Foods of the Mediterranean diet: garlic and Mediterranean legumes

The Mediterranean diet is a dietary regime derived from the one followed by the ancient civilizations of the Mediterranean region. It is characterized by many healthy constituents, among which are cereals, legumes, fruits, vegetables, olives, and white meat. Many studies suggest that this dietary regime is the key to obtaining a healthy and long life, like that of the Mediterranean peoples. Despite its popularity among health professionals, this diet is still confined to a certain geographical area of the world. Due to globalization and the modern busy lifestyle, this cultural diet is losing ground even in its home region, with more and more people embracing the so-called Western diet. An awareness of health benefits of the individual components of the Mediterranean diet will therefore draw attention from all over the world to this healthy and affordable dietary pattern, which can not only improve the overall health, but also reduce the risk of developing chronic and infectious diseases. In this regard, garlic and Mediterranean legumes present a huge repertoire of phytochemicals having both nutritive and nutraceutical properties, which therefore should be included in our daily dietary routines in moderate proportions. This narrative review aims at summarizing the principal components and health benefits of the Mediterranean diet, in particular of garlic and legumes.

Polyphenols, Saponins and Phytosterols in Lentils and Their Health Benefits: An Overview

The lentil (Lens culinaris L.) is one of the most important legumes (family, Fabaceae). It is a natural functional food rich in many bioactive compounds, such as polyphenols, saponins and phytosterols. Several studies have demonstrated that the consumption of lentils is potentially important in reducing the incidence of a number of chronic diseases, due to their bioactive compounds. The most common polyphenols in lentils include phenolic acids, flavan-3-ol, flavonols, anthocyanidins, proanthocyanidins or condensed tannins, and anthocyanins, which play an important role in the prevention of several degenerative diseases in humans, due to their antioxidant activity. Furthermore, lentil polyphenols are reported to have antidiabetic, cardioprotective and anticancer activities. Lentil saponins are triterpene glycosides, mainly soyasaponins I and βg. These saponins have a plasma cholesterol-lowering effect in humans and are important in reducing the risk of many chronic diseases. Moreover, high levels of phytosterols have been reported in lentils, especially in the seed coat, and β-sitosterol, campesterol, and stigmasterol are the most abundant. Beyond their hypocholesterolemic effect, phytosterols in lentils are known for their anti-inflammatory activity. In this review, the current information on the nutritional composition, bioactive compounds including polyphenols, saponins and phytosterols, and their associated health-promoting effects are discussed.

Protective effects of the phenolic compounds from mung bean hull against H2O2-induced skin aging through alleviating oxidative injury and autophagy in HaCaT cells and HSF cells

To add value to food waste and seek skin aging suppressor, petroleum ether, ethyl acetate, n-butanol and water phenolic extracts were produced from mung bean hulls subjected to ultrasound-assisted ethanolic extraction. The four extracts all contained protocatechuic acid, isovitexin, vitexin, caffeic acid, 4-coumaric acid, ferulic acid, rutin and chlorogenic acid (revealed by UHPLC-MS/MS). The effects of the four extracts and their main phenolic compounds against H₂O₂-caused cell damage and aging in HaCaT and HSF cells were examined (including cell viability, ROS, MDA, SOD, GSH-px and β-galactosidase levels). The four extracts and the eight phenolic compounds exhibited different protective effects on H₂O₂-treated HaCaT/HSF cells viability, with the ethyl acetate extract among the extracts, and isovitexin and vitexin among the eight compounds, exerting the greatest protection. Therefore, isovitexin and vitexin may be the key oxidative stress and autophagy modulators of mung bean hull, and they inhibit skin aging and damage likely through suppressing Nrf2/keap1/HO-1 related oxidative damage and LC3II/p62/GATA4 related autophagy.

An update on nutritional profile, phytochemical compounds, health benefits, and potential applications in the food industry of pulses seed coats: A comprehensive review

Pulses, as a sustainable source of nutrients, are an important choice for human diets, but vast quantities of seed coats generated in pulses processing are usually discarded or used as low-value ruminant feed. It has been demonstrated that pulses seed coats are excellent sources of dietary nutrients and phytochemicals with potential health benefits. With growing interest in the sustainable use of resources and the circular economy, utilization of pulses seed coats to recover these valuable components is a core objective for their valorization and an important step toward agricultural sustainability. This review comprehensively provides a comprehensive insight on the nutritional and phytochemical profiles presented in pulses seed coats and their health benefits obtained from the findings of in vitro and in vivo studies. Furthermore, in the food industry, pulses seed coats can be acted as potential food ingredients with nutritional, antioxidant and antimicrobial characteristics or as the matrix or active components of films for food packaging and edible coatings. A better understanding of pulses seed coats may provide a reference for increasing the overall added value and realizing the pulses' sustainable diets.

Isolation of bioactive peptides and multiple nutraceuticals of antidiabetic and antioxidant functionalities through sprouting: Recent advances

The employment of proteases directly from enzymes or indirectly from microorganisms during fermentation for the purpose of proteolysis of food proteins has been the conventional trend for the derivation of bioactive peptides from food matrices. However, recent studies have shown that inherent protease enzymes can be activated for this activity for vegetable foods using the sprouting process. The benefits of ease of operation, and reduced processing costs are formidable advantages for the optimal consideration of this technique. On another note, the demand for functional foods with therapeutic health effects has increased in recent years. Globally, plant foods are perceived as dietetic choices bearing sufficient quantities of concomitant nutraceuticals. In this manuscript, the sprouting route for the isolation of peptides and glucosinolates, and for the enhancement of total phenolic contents, polyunsaturated fatty acid profiles, and other bioactive constituents was explored. Advances regarding the phytochemical transformations in the course of sprouting, the therapeutic functionalities, and microbiological safety concerns of vegetable sprouts are delineated. In addition, consumption of vegetable sprouts has been shown to be more efficient in supplying nutraceutical components relative to their unsprouted counterparts. Biochemical mechanisms involving the inhibition of digestive enzymes such as α-amylase, β-glucosidase, and dipeptidyl peptidase IV (DPP-IV), single electron transfer, and metal chelation, for impartation of health benefits, have been reported to occur from bioactive components isolated from vegetable sprouts. PRACTICAL APPLICATIONS: Sprouting initiates proteolysis of vegetable proteins for the release of bioactive peptides. Abiotic stresses can be used as elicitors during the sprouting process to achieve enhanced phytochemical profiles of sprouts. Sprouting is a relatively more convenient approach to the improvement of the health benefits of vegetable foods. Vegetable sprouts are potential for the management of metabolic syndrome disorders.

Interactive deciphering electron-shuttling characteristics of agricultural wastes with potential bioenergy-steered anti-COVID-19 activity via microbial fuel cells

Background

This first-attempt study explored indigenous herbs from agricultural waste with bioenergy and biorefinery-stimulating potentials for possible anti-COVID-19 drug development. As prior novel study revealed, medicinal herbs abundant in ortho-dihydroxyl substituents and flavonoid-bearing chemicals were likely not only electron shuttle (ES)-steered, but also virus transmission-resisted.

Methods

Herbal extract preparation from agricultural wastes were implemented via traditional Chinese medicine (TCM) decoction pot. After filtration and evaporation, a crude extract obtained was used for evaluation of bioenergy-stimulating and electron-mediating characteristics via microbial fuel cells (MFCs). Combined with cyclic voltammetric analysis, MFCs provided a novel platform to distinguish electron shuttles from antioxidants with electron-transfer steered antiviral potentials of herbal extracts.

Significant findings

After 50 serial cyclic voltammogram traces, considerable ES activities of herbal extracts still stably remained, indicating that possible medication-associated capabilities could be persistent. This work also extended to explore bioenergy-stimulating herbs from agricultural waste recycling for bioenergy and biorefinery applications. Water extract of Coffea arabica was more biotoxic than ethanolic extract, resulting in its lower power-generating capability. The findings revealed that water extract of Trichodesma khasianum and Euphorbia hirta could exhibit considerable bioenergy-enhancing effects. For cradle-to-cradle circular economy, agricultural waste could be specifically screened for possible regeneration of value-added anti-COVID-19 drugs via bioenergy selection.

Antioxidant Activities of Aqueous Extracts and Protein Hydrolysates from Marine Worm Hechong (Tylorrhynchus heterochaeta)

Hechong (Tylorrhynchus heterochaeta) is an edible marine worm widely distributed in the estuary area. The objective of this study is to determine the antioxidant activities of extracts and protein hydrolysates from Hechong. Results showed that the aqueous extracts of steamed Hechong had the highest antioxidant values using the methods of DPPH, ABTS, and FRAP testing (76.29 μmol TE/g, 181.04 μmol TE/g, and 10.40 mmol Fe²⁺/100 g, respectively). Furthermore, protein hydrolysates of Hechong were observed significant antioxidant activities when compared to crude Hechong. The purification was carried out by DEAE-52 cellulose and Sephadex G-100 column chromatography. The microspatial structure of glycoprotein showed fibrous shapes and cracks with uniform distribution. The study has concluded that the extract and protein hydrolysates of Hechong have significant antioxidant activities, which is merited to be further investigated in the food and pharmaceutical fields.

Variability of Anthocyanin Concentrations, Total Metabolite Contents and Antioxidant Activities in Adzuki Bean Cultivars

In this study, adzuki bean cultivars including Arari, Chilbopat, Geomguseul, and Hongeon were recently cultivated, and the concentrations of seven individual anthocyanins were determined in their seed coats for the first time. Moreover, the variations of total saponin content (TSC), total phenolic content (TPC), 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, Trolox equivalent antioxidant capacity (TEAC), and ferric reducing antioxidant power (FRAP) between defatted and undefatted extracts of whole seeds, seed coats, and dehulled seeds of each were analyzed. The anthocyanins were detected only in the black seed-coated cultivars and delphinidin-3-O-glucoside was dominant in both Geomguseul (12.46 mg/g) and Chilbopat (10.88 mg/g) followed by delphinidin-3-O-galactoside. TSC and TPC were in the ranges of 16.20−944.78 mg DE/g and 0.80−57.35 mg GAE/g, respectively, and each decreased in the order of seed coats > whole seeds > dehulled seeds regardless of extract type. The antioxidant activities also showed similar patterns of variation. Geomguseul seed coats outweighed the remaining cultivars in terms of TPC and FRAP activity (p < 0.05). Generally, significant variations of metabolite contents and antioxidant activities were observed between cultivars and across their seed parts (p < 0.05). Thence, black seed-coated adzuki beans could be excellent sources of anthocyanins and antioxidants.

Effect of Microwave Treatment on Adzuki Beans (Vigna angularis L.) under Dry State-Analyzing Microstructure, Water Absorption, and Antioxidant Properties

In this study, a microwave was used on adzuki beans (Arari and Geomguseul) without water, in order to investigate their changes in microstructure, water absorption, and antioxidative properties. As the microwave treatment time increased (2450 MHz, 0 to 60 s), the lightness, redness, and yellowness were reduced, and moisture content significantly decreased in both varieties. The microstructure space between the seed coat, cotyledon, and pores within the cotyledon were observed, due to the loss of moisture. Regardless of microwave treatment, the water absorption behavior of the adzuki beans was sigmoidal. However, the water absorption kinetics of Arari increased after microwave treatment, whereas with microwave-treated Geomguseul, the water absorption rate decreased, compared to the control, except for the sample treated for 30 s. During soaking, the water absorption and softening rates in the microwave-treated adzuki bean were twice as fast as the untreated beans. Antioxidant activity, total phenolic compounds, and total flavonoid compounds were greatly improved by microwave treatment. These results indicate that microwave treatment affects the color, hydration, and bioactive compounds, and it can be used as a pretreatment method before processing adzuki beans.

Antioxidant Capacity and Antiplatelet Activity of Aqueous Extracts of Common Bean (Phaseolus vulgaris L.) Obtained with Microwave and Ultrasound Assisted Extraction

Phaseolus vulgaris L. has beneficial effects on several chronic non-communicable diseases (e.g., cardiovascular diseases) related to oxidative stress. This redox state may influence platelet activation and aggregation; which is crucial in thrombus formation. In this work, the antiplatelet and antioxidant potential of aqueous extracts obtained by green processes, microwave-assisted extraction and ultrasound-assisted extraction, from 25 landraces of common beans were investigated. Phenol content and antioxidant potential were determined using the Folin-Ciocalteu method, total monomeric anthocyanin and ORAC assay, respectively. The antiplatelet potential of the extracts was explored by turbidimetry. Microwave extraction showed higher phenol content and antioxidant activity in most extracts. Soja landrace extract obtained by microwave-assisted extraction showed higher phenol content and antioxidant activity (893.45 ± 87.30 mg GAE/g and 35,642.85 ± 2588.88 ORAC μmolTE/g, respectively). Although most of the extracts obtained by microwave-assisted extraction showed antiplatelet activity, the extract of Hallado Aleman landrace obtained by ultrasound-assisted extraction (IC50 = 0.152 ± 0.018 mg/mL) had the highest antiplatelet potential. The extraction method, MAE and UAE, influences the biological potential of the beans, specifically the antiplatelet activity and antioxidant activity. The functional value of this legume for direct consumption by the population was evidenced, as well as its inclusion in food formulations.

Optimization Extraction and Antioxidant Activity of Crude Polysaccharide from Chestnut Mushroom (Agrocybe aegerita) by Accelerated Solvent Extraction Combined with Response Surface Methodology (ASE-RSM)

The present work is conducted to investigate the optimal extraction technology of polysaccharide from chestnut mushroom (Agrocybe aegerita) using a new method based on accelerated solvent extraction combined with response surface methodology (ASE-RSM). The conventional reflux extraction (CRE) method and ultrasonic-assisted extraction (UAE) method were also carried out. Additionally, the in vitro antioxidant activities, including ABTS and DPPH assay, were evaluated. The RSM method, based on a three level and three variable Box–Behnken design (BBD), was developed to obtain the optimal combination of extraction conditions. In brief, the polysaccharide was optimally extracted with water as extraction solvent, extraction temperature of 71 °C, extraction time of 6.5 min, number of cycles of 3, and extraction pressure of 10 MPa. The 3D response surface plot and the contour plot derived from the mathematical models were applied to determine the optimal conditions. Under the above conditions, the experimental value of polysaccharide yield was 19.77 ± 0.12%, which is in close agreement with the value (19.81%) predicted by the model. These findings demonstrate that ASE-RSM produce much higher polysaccharide and consumed environmentally friendly extraction and solvent systems, have less extraction discrimination and shorter time and provide scientific basis for industrialization of polysaccharide extraction. Moreover, it was proved that the polysaccharide had the potential ability to scavenge ABTS and DPPH.

Adzuki bean (Vigna angularis): Chemical compositions, physicochemical properties, health benefits, and food applications

Adzuki bean (Vigna angularis), also called red bean, is a legume of Fabaceae (Leguminosae) family. This crop is native to East Asia and is also commercially available in other parts of the world. It is becoming a research focus owing to its distinct nutritional properties (e.g., abundant in polyphenols). The diverse health benefits and multiple utilization of this pulse are associated with its unique composition. However, there is a paucity of reviews focusing on the nutritional properties and potent applications of adzuki beans. This review summarizes the chemical compositions, physicochemical properties, health benefits, processing, and applications of adzuki beans. Suggestions on how to better utilize the adzuki bean are also provided to facilitate its development as a functional grain. Adzuki bean and its components can be further developed into value-added and nutritionally enhanced products.

Extraction of Phenolic and Flavonoid Compounds from Mung Bean (Vigna radiata L.) Seed Coat by Pressurized Liquid Extraction

Mung bean seed coat (MBC) is a by-product of the mung bean processing industry. It contains a large number of phenolic compounds with therapeutic anti-inflammatory, anti-diabetic and antioxidant properties. This research aimed to investigate the optimum conditions for phenolic and flavonoid extraction from MBC by pressurized liquid extraction (PLE). Response surface methodology (RSM) was used to study the effects of temperature (80-160 °C), pressure (1200-1800 psi) and ethanol concentration (5-95%) on total phenolic content (TPC), total flavonoid content (TFC) and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity (ABTS). Scale-up extraction was also performed. The optimum conditions for extraction were 160 °C, 1300 psi and 50% ethanol. Under optimum conditions, the TPC was 55.27 ± 1.14 mg gallic acid equivalent (GAE)/g MBC, TFC was 34.04 ± 0.72 mg catechin equivalent (CE)/g MBC and ABTS scavenging activity was 195.05 ± 2.29 mg trolox equivalent (TE)/g MBC. The TFC and ABTS scavenging activity of the extracts obtained at the pilot scale (10 L) was not significantly different from the laboratory scale, while TPC was significantly increased. The freeze-dried MBC extract contained vitexin and isovitexin 130.53 ± 17.89, 21.21 ± 3.22 mg/g extract, respectively. In conclusion, PLE was able to extract phenolics, flavonoids with ABTS scavenging activity from MBC with the prospect for future scale-up for food industry.

Black Truffle Extract Exerts Antidiabetic Effects through Inhibition of Inflammation and Lipid Metabolism Regulation

Black truffle, a culinary and medical fungus, is highly valued worldwide for its nutritional and therapeutic importance. To enhance the existing knowledge about the beneficial properties, this study investigates the antioxidant, antihyperlipidemic, and anti-inflammatory effects of black truffle extract in in vitro biochemical assays and animal study. Briefly, black truffle extract was administered orally to treat streptozotocin- (STZ-) induced diabetic Wistar rats for 45 days. At the end of the experimental duration, rats were sacrificed to perform biochemical and gene expression analyses related to lipid regulatory and inflammatory pathways. Our results indicated that total cholesterol, triglycerides, free fatty acids, phospholipids, and low-density lipoprotein in different tissues and circulation were significantly increased in diabetic rats. Furthermore, the β-hydroxy β-methylglutaryl-CoA enzyme was also significantly increased; lipoprotein lipase and lecithin-cholesterol acyltransferase enzymes were significantly decreased in diabetic rats. However, the above conditions were reversed upon black truffle extract feeding. Furthermore, black truffle extract was also found to downregulate the expression of proinflammatory cytokines (tumor necrosis factor-α and interleukin-6) and lipid regulatory genes (serum regulatory element-binding protein-1 and fatty acid synthase). The truffle extract-treated effects were comparable to glibenclamide and medication commonly used to treat diabetes mellitus. Overall, our results suggested that black truffle possesses strong antihyperlipidemic and anti-inflammatory effects on diabetic rats. These findings will enhance the current knowledge about the therapeutic importance of black truffles. They might be exploited as a possible food supplement or even as a natural source of pharmaceutical agents for diabetes prevention and treatment.

Revealing the Hypoglycemic Effects and Mechanism of GABA-Rich Germinated Adzuki Beans on T2DM Mice by Untargeted Serum Metabolomics

Type 2 diabetes mellitus (T2DM) is one of the most common metabolic diseases, and exploring strategies to prevent and treat diabetes has become extremely important. In recent decades the search for new therapeutic strategies for T2DM involving dietary interventions has attracted public attention. We established a diabetic mouse model by feeding mice a high-fat diet combined with injection of low-dose streptozotocin, intending to elucidate the effects and possible mechanisms of different dosages of γ-aminobutyric acid (GABA)-rich germinated adzuki beans on the treatment of diabetes in mice. The mice were treated for 6 weeks either with increasing doses of GABA-enriched germinated adzuki beans, with non-germinated adzuki beans, with GABA, or with the positive control drug metformin. Then, the blood glucose levels and blood lipid biochemical indicators of all the mice were measured. At the same time, serum differential metabolite interactions were explored by UPLC-Q/TOF-MS-based serum metabolomic analysis. The results showed that body weight and fasting blood glucose levels were significantly reduced (P < 0.05). We also report improved levels of total cholesterol, triglycerides, aspartate aminotransferase, alanine aminotransferase, urea, and serum creatinine. We observed a significant improvement in the homeostasis model assessment of the beta cell function and insulin resistance (HOMA-β and HOMA-IR) scores (P < 0.05) in the group of mice treated with the highest dose of GABA-enriched germinated adzuki beans. In addition, the metabolic profiles of the serum were analyzed, and 31 differential metabolites including amino acids and lipids were obtained. According to the Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis, this was found to be correlated with nine significantly enriched metabolic pathways involving the up-regulation of levels of L-serine, SM (d18:1/22:1(13Z)), L-histidine, creatine, and 3-indoleacetic acid. Our data suggest that the hypoglycemic effect of GABA-enriched germinated adzuki beans on diabetic mice may be related to improving tryptophan metabolism, glycerol phospholipid metabolism, sphingosline metabolism, and the glycine, serine, and threonine metabolic pathways. This study provides a reference for the application of GABA-enriched germinated foods in type 2 diabetes and could provide a cue for searching biomarkers to be adopted for T2DM diagnosis.

iTRAQ based protein profile analysis revealed key proteins involved in regulation of drought-tolerance during seed germination in Adzuki bean

Adzuki bean is an important legume crop due to its high-quality protein, fiber, vitamins, minerals as well as rich bioactive substances. However, it is vulnerable to drought at the germination stage. However, little information is available about the genetic control of drought tolerance during seed germination in adzuki bean. In this study, some differential expression proteins (DEPs) were identified during seed germination between the drought-tolerant variety 17235 and drought-sensitive variety 17033 in adzuki bean using iTRAQ method. A total of 2834 proteins were identified in the germinating seeds of these two adzuki beans. Compared with the variety 17033, 87 and 80 DEPs were increased and decreased accumulation in variety 17235 under drought, respectively. Meanwhile, in the control group, a few DEPs, including 9 up-regulated and 21 down-regulated proteins, were detected in variety 17235, respectively. GO, KEGG, and PPI analysis revealed that the DEPs related to carbohydrate metabolism and energy production were significantly increased in response to drought stresses. To validate the proteomic function, the ectopic overexpression of V-ATPase in tobacco was performed and the result showed that V-ATPase upregulation could enhance the drought tolerance of tobacco. The results provide valuable insights into genetic response to drought stress in adzuki bean, and the DEPs could be applied to develop biomarkers related to drought tolerant in adzuki bean breeding projects.

Protective mechanism of mung bean coat against hyperlipidemia in mice fed with a high-fat diet: insight from hepatic transcriptome analysis

Mung bean coat (MBC) is a good source of dietary fibre and phenolic compounds with medical properties, and can alleviate metabolic diseases. In the present study, the effects of MBC on high fat diet (HFD)-induced hyperlipidemia mice were evaluated, and the underlying mechanisms of MBC against hyperlipidemia from hepatic transcriptional analysis were explored. Four groups of mice were fed a normal control diet or a HFD with or without MBC supplementation (6%, w/w) for 12 weeks. The results demonstrated that MBC supplementation could effectively alleviate HFD-induced obese symptoms, such as body weight gain and white adipose tissue accumulation. Notably, the serum lipid profiles, including total triglyceride, total cholesterol, and low-density lipoprotein cholesterol, were significantly lowered, accompanied by a significant improvement in hepatic steatosis. RNA-sequencing analysis indicated 1126 differential expression genes responding to MBC supplementation, and the PPAR signaling pathway was significantly enriched. Furthermore, MBC supplementation could significantly upregulate the transcriptional expression of lipid transformation (lipidolysis)-related genes (Cpt1b, Cyp7a1, and PPAR-α) and downregulate the transcriptional expression of lipid synthesis-related genes (Scd1, Cd36, and PPAR-γ) to protect against the HFD-induced hyperlipidemia, and they were confirmed by qRCR and western blotting validation. Taken together, the present study provides valuable information for understanding the curative effects and action mechanism of MBC in alleviating hyperlipidemia, and thus may contribute to the development and application of MBC as functional foods or dietary supplement to protect against hyperlipidemia.

Nutritional, phytochemical and antioxidant properties of 24 mung bean (Vigna radiate L.) genotypes

Abstract

This study aimed to investigate the proximate and phytochemicals present in seeds of 24 mung bean (Vigna radiate L.) genotypes from four provinces of China for estimating their nutritional and antioxidant properties. Proximate analysis of mung bean genotypes revealed that starch, protein, fat, ash and water-soluble polysaccharide ranged from 39.54–60.66, 17.36–24.89, 4.24–12.18, 2.78–3.53 and 1.99–2.96 g/100 g respectively. The five principal fatty acids detected in mung beans were stearic acid, palmitic acid, linoleic acid, oleic acid, and linolenic acid. The contents of insoluble-bound phenolic compounds, soluble phenolic compounds, and flavonoids ranged from 0.78 to 1.5 mg GAE g− 1, 1.78 to 4.10 mg GAE g− 1, and 1.25 to 3.52 mg RE g− 1, respectively. The black seed coat mung bean genotype M13 (Suheilv 1) exhibited highest flavonoid and phenolic contents which showed strong antioxidant activity. Two flavonoids (vitexin and isovitexin) and four phenolic acids (caffeic, syringic acid, p-coumaric, and ferulic acids) were identified by HPLC. Vitexin and isovitexin were the major phenolic compounds in all mung bean genotypes. The content of soluble phenolic compounds had positive correlation with DPPH (r2 = 0.713) and ABTS (r2 = 0.665) radical scavenging activities. Principal component analysis indicated that the first two principal components could reflect most details on mung bean with a cumulative contribution rate of 66.1%. Twenty-four mung bean genotypes were classified into four groups based on their phenolic compounds contents and antioxidant activities. The present study highlights the importance of these mung bean genotypes as a source of nature antioxidant ingredient for the development of functional foods or a source of health promoting food.

Graphical Abstract