Mung bean coat ameliorates hyperglycemia and the antioxidant status in type 2 diabetic db/db mice

Dietary mung bean as promising food for human health: gut microbiota modulation and insight into factors, regulation, mechanisms and therapeutics-an update

Plant-based functional foods have gained wider attention in current scenario with mung bean harboring several bioactive compounds with promising gut health benefits and pharmacological importance. Consumption of mung bean has a positive impact on beneficial gut microbes and microbial metabolite production. The effects of dietary mung bean on gut microbial homeostasis and the management of gut-related diseases along with the possible mechanism of action, have been highlighted through this review paving a way for a promising role of dietary mung bean as a functional food in the management of gut-related diseases for example mung bean peptides can help not only in treating prediabetes but also delaying the aging process by targeting the intestinal microflora. In addition, expanding our knowledge of how diets affect host health and disease, including the effects of mung bean dietary components on gut microbiota-derived metabolites, will eventually allow for the development of tailored diets and nutrients.

Pathophysiology of diabetic hepatopathy and molecular mechanisms underlying the hepatoprotective effects of phytochemicals

Patients with diabetes are at risk for liver disorders including glycogen hepatopathy, non-alcoholic fatty liver disease, cirrhosis, and hepatic fibrosis. The pathophysiological mechanisms behind diabetic hepatopathy are complex, some of them include fatty acid accumulation, increased reactive oxygen species, increased advanced glycation end-products, hyperactivity of polyol pathways, increased apoptosis and necrosis, and promotion of fibrosis. A growing number of studies have shown that herbal extracts and their active phytochemicals have antihyperglycemic properties and beneficial effects on diabetic complications. The current review, for the first time, focused on herbal agents that showed beneficial effects on diabetic hepatopathy. For example, animal studies have shown that Moringa oleifera and Morus alba improve liver function in both type-1 and type-2 diabetes. Also, evidence from clinical trials suggests that Boswellia serrata, Juglans regia, Melissa officinalis, Portulaca oleracea, Silybum marianum, Talapotaka Churna, and Urtica dioica reduce serum liver enzymes in diabetic patients. The main active ingredient of these plants to protect the liver seems to be phenolic compounds such as niazirin, chlorogenic acid, resveratrol, etc. Mechanisms responsible for the hepatoprotective activity of herbal agents include improving glucose metabolism, restoring adipokines levels, antioxidant defense, and anti-inflammatory activity. Several signaling pathways are involved in hepatoprotective effects of herbal agents in diabetes, such as phosphoinositide 3-kinase, adenosine monophosphate-activated protein kinase, mitogen-activated protein kinase, and c-Jun NH2-terminal kinase.

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.

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.

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.

Gut Microbiota Modulation, Anti-Diabetic and Anti-Inflammatory Properties of Polyphenol Extract from Mung Bean Seed Coat (Vigna radiata L.)

The present study investigated the gut health, anti-diabetic, and anti-inflammatory activities of mung bean seed coat extract (MSE). MSE was obtained by pressurized liquid extraction (PLE) using 50% ethanol as the extracting solvent. After 24 h of in vitro human fecal fermentation, MSE exhibited higher productions of total short-chain fatty acids (SCFA) than those of the control group (CON) and other polyphenol-rich substrates, including gallic acid (GA) and vitexin (VIT) (p > 0.05), but still lower than the fructo-oligosaccharide (FOS). In 16S-rRNA next-generation sequencing, MSE regulated the composition of gut microbiota by stimulating the growth of the beneficial bacteria Enterococcus, Ruminococcus, Blautia, and Bacteroides and decreasing the growth of the potential pathogenic bacteria Escherichia-Shigella. Similarly, qPCR showed increased numbers of Bifidobacterium, Lactobacillus, Faecalibacterium prausnitzii, and Prevotella, compared with those of CON (p < 0.05). MSE also reduced reactive oxygen species and increased glucose uptake in insulin-resistant HepG2 cells dose-dependently. The anti-inflammatory activity of MSE was observed in LPS-stimulated THP-1 monocytes with the reduction of TNFα, IL-1β, IL-6, and IL-8 genes. The data demonstrated the potential applications of MSE as a dietary supplement with gut health benefits and its ability to mitigate diabetes and inflammatory-related diseases.

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.

Dietary supplementation with mung bean coat alleviates the disorders in serum glucose and lipid profile and modulates gut microbiota in high-fat diet and streptozotocin-induced prediabetic mice

As amajor by-product of mung bean processing, mung bean coat (MBC), which is rich in polyphenols and dietary fiber, is deemed to be mainly responsible for the health benefits of mung bean. However, its beneficial effects on the hyperglycemia, hyperlipidemia, and gut microbiota composition in prediabetic mice is not fully understood. The objective of this study was to investigate the efficacy of MBC in alleviating high-fat diet and streptozotocin-induced prediabetes. Herein, compared with the model control, dietary supplementation with MBC (3%, w/w) for 12 weeks significantly decreased the fasting blood glucose (24.60%), total cholesterol (15.72%), triglyceride (14.41%), and low-density lipoprotein cholesterol (22.45%). Furthermore, the improvements in glucose tolerance were reflected in the reduction of the area under the curve (AUC) and incremental AUC by approximately 23.08% and 51.18%, respectively. 16S rRNA gene sequencing of fecal microbiota suggested that MBC promoted the enrichment of beneficial bacteria (Roseburia and Bifidobacterium) and the production of short-chain fatty acids. All of the results from this study provided a scientific reference for avoiding the functional ingredients waste of MBC and expanding its application value.

A comparison between whole mung bean and decorticated mung bean: beneficial effects on the regulation of serum glucose and lipid disorders and the gut microbiota in high-fat diet and streptozotocin-induced prediabetic mice

The aim of this study is to investigate the beneficial effects of whole mung bean (WMB) and decorticated mung bean (DMB) on the regulation of serum glucose and lipid disorders in high-fat diet (HFD) and streptozotocin (STZ)-induced prediabetic mice, and to further explore their gut microbiota modulatory effects. In the present study, the ability of mung bean-based diets to combat prediabetes-related metabolic disorders was determined by assessing the changes in the physiological, biochemical, and histological parameters, and the gut microbiota composition of prediabetic mice. The supplementation of both WMB and DMB can effectively alleviate HFD and STZ-induced impaired glucose tolerance (P < 0.05), which was accompanied by improvements in pancreatic β-cell damage and hepatic steatosis. However, only WMB supplementation significantly decreased the fasting blood glucose and fasting serum insulin levels by sensitizing insulin action (P < 0.05), and reduced the serum lipid profiles and glycosylated serum protein levels (P < 0.05). Furthermore, high-throughput pyrosequencing of the 16S rRNA gene revealed that WMB and DMB supplementation could prevent HFD and STZ-induced gut microbiota dysbiosis, especially for the enrichment of some benign bacteria, such as Bifidobacterium and Akkermansia, and the reduction of some harmful bacteria (Staphylococcus and Enterococcus). Overall, although decortication processing had an impact on the beneficial effects of mung bean, it did not cause the loss of all health benefits.

Water Extract of Mungbean (Vigna radiata L.) Inhibits Protein Tyrosine Phosphatase-1B in Insulin-Resistant HepG2 Cells

The present study aimed to investigate the effects of mungbean water extract (MWE) on insulin downstream signaling in insulin-resistant HepG2 cells. Whole seed mungbean was extracted using boiling water, mimicking a traditional cooking method. Vitexin and isovitexin were identified in MWE. The results showed that MWE inhibited protein tyrosine phosphatase (PTP)-1B (IC₅₀ = 10 μg/mL), a negative regulator of insulin signaling. MWE enhanced cellular glucose uptake and altered expression of genes involved in glucose metabolism, including forkhead box O1 (FOXO1), phosphoenolpyruvate carboxykinase (PEPCK), and glycogen synthase kinase (GSK)-3β in the insulin-resistant HepG2 cells. In addition, MWE inhibited both α-amylase (IC₅₀ = 36.65 mg/mL) and α-glucosidase (IC₅₀ = 3.07 mg/mL). MWE also inhibited the formation of advanced glycation end products (AGEs) (IC₅₀ = 2.28 mg/mL). This is the first study to show that mungbean water extract increased cellular glucose uptake and improved insulin sensitivity of insulin-resistant HepG2 cells through PTP-1B inhibition and modulating the expression of genes related to glucose metabolism. This suggests that mungbean water extract has the potential to be a functional ingredient for diabetes.

Novel Short-Clustered Maltodextrin as a Dietary Starch Substitute Attenuates Metabolic Dysregulation and Restructures Gut Microbiota in db/db Mice

Molecular structure of starch in daily diet is closely associated with diabetes management. By enzymatically reassembling α-1,4 and α-1,6 glycosidic bonds in starch molecules, we have synthesized an innovative short-clustered maltodextrin (SCMD) which slowly releases glucose during digestion. Here, we investigated the potential benefits of the SCMD-containing diet using diabetic db/db mice. As compared to a diet with normal starch, this dietary style greatly attenuated hyperglycemia and repaired symptoms associated with diabetes. Additionally, in comparison with acarbose (an α-glucosidase inhibitor) administration, the SCMD-containing diet more effectively accelerated brown adipose activation and improved energy metabolism of db/db mice. Furthermore, the SCMD-containing diet was a more suitable approach to improving the intestinal microflora than acarbose administration, especially the proliferation of Mucispirillum, Akkermansia, and Bifidobacterium. These results reveal a novel strategy for diabetes management based on enzymatically rebuilding starch molecules in the daily diet.

Beneficial effects of mung bean seed coat on the prevention of high-fat diet-induced obesity and the modulation of gut microbiota in mice

PURPOSE

Our recent study has reported that whole mung bean showed better beneficial effects on high-fat diet (HFD)-induced obesity and gut microbiota disorders when compared with the decorticated mung bean at the same intervention dose level, suggesting that the mung bean seed coat (MBC) may play a crucial role in its health benefits. This study aims to investigate whether MBC has beneficial benefits on the prevention of HFD-induced obesity and the modulation of gut microbiota in mice when it was supplemented in HFD.

METHODS

Herein, male C57BL/6 J mice were fed with normal control diet, HFD, and HFD supplemented with MBC (3-6%, w/w) for 12 weeks. The changes in physiological, histological, biochemical parameters, serum endotoxin, proinflammatory cytokines, and gut microbiota composition of mice were determined to assess the ability of MBC to alleviate HFD-induced obesity and modulate gut microbiota disorders in mice.

RESULTS

MBC supplementation exhibited significant reductions in the HFD-induced adiposity, fat accumulation, serum lipid levels, lipopolysaccharide, and proinflammatory cytokines concentrations (P < 0.05), which was accompanied by improvements in hepatic steatosis and adipocyte size. Especially, the elevated fasting blood glucose and insulin resistance were also significantly improved by MBC supplementation (P < 0.05). Furthermore, high-throughput sequencing of the 16S rRNA gene revealed that MBC could normalize HFD-induced gut microbiota dysbiosis. MBC not only could promote the bloom of Akkermansia, but also restore several HFD-dependent taxa (Blautia, Ruminiclostridium_9, Bilophila, and unclassified_f_Ruminococcaceae) back to normal status, co-occurring with the decreases in obesity-related indices.

CONCLUSIONS

This study provides evidence that MBC may be mainly responsible for the beneficial effects of whole mung bean on preventing the HFD-induced changes, thus enlarging the application value of MBC.

Integrated Transcriptomic and Metabolic Framework for Carbon Metabolism and Plant Hormones Regulation in Vigna radiata during Post-Germination Seedling Growth

During mung bean post-germination seedling growth, various metabolic and physiological changes occurred, leading to the improvement of its nutritional values. Here, transcriptomic and metabolomic analyses of mung bean samples from 6-hour, 3-day and 6-day after imbibition (6-HAI, 3-DAI, and 6-DAI) were performed to characterize the regulatory mechanism of the primary metabolites during the post-germination seedling growth. From 6-HAI to 3-DAI, rapid changes in transcript level occurred, including starch and sucrose metabolism, glycolysis, citrate cycle, amino acids synthesis, and plant hormones regulation. Later changes in the metabolites, including carbohydrates and amino acids, appeared to be driven by increases in transcript levels. During this process, most amino acids and monosaccharides kept increasing, and accumulated in 6-day germinated sprouts. These processes were also accompanied with changes in hormones including abscisic acid, gibberellin, jasmonic acid, indole-3-acetic acid, etc. Overall, these results will provide insights into molecular mechanisms underlying the primary metabolic regulation in mung bean during post-germination seedling growth.

Mungbean seed coat water extract inhibits inflammation in LPS-induced acute liver injury mice and LPS-stimulated RAW 246.7 macrophages via the inhibition of TAK1/IκBα/NF-κB

Inflammation plays an important role in pathogenesis and progression of many chronic diseases. Although, anti-inflammatory activities of mungbean have been suggested, the underlying mechanism have not been fully understood. The present study aimed to reveal the anti-inflammatory effects of mungbean seed coat water extract (MSWE) in lipopolysaccharide (LPS)-stimulated inflammation in RAW 246.7 macrophages and LPS-induced acute liver injury mice. MSWE pretreatment downregulated the elevated expression of inflammatory markers induced by LPS in the transcriptional and protein level. MSWE inhibited NF-κB activation through the suppression of phosphorylated p65 subunit, IκBα degradation, and transforming growth factor-β-activated kinases 1 (TAK1) phosphorylation in LPS-stimulated RAW 246.7 cells. Vitexin, the major flavonoid in MSWE showed similar effects. In in vivo experiments, we found that oral administration of MSWE downregulated iNOS expression in LPS-induced acute liver injury mice. The mRNA expression of inflammatory markers and macrophage infiltration was also decreased in the livers. Collectively, MSWE exerts anti-inflammatory role, in part possibly through its active compound vitexin, by inhibiting NF-κB activation via inhibition of TAK1 phosphorylation and IκBα degradation. This suggests that MSWE is beneficial to combat various inflammatory diseases.

Mung Bean (Vigna radiata L.): Bioactive Polyphenols, Polysaccharides, Peptides, and Health Benefits

Mung bean (Vigna radiata L.) is an important pulse consumed all over the world, especially in Asian countries, and has a long history of usage as traditional medicine. It has been known to be an excellent source of protein, dietary fiber, minerals, vitamins, and significant amounts of bioactive compounds, including polyphenols, polysaccharides, and peptides, therefore, becoming a popular functional food in promoting good health. The mung bean has been documented to ameliorate hyperglycemia, hyperlipemia, and hypertension, and prevent cancer and melanogenesis, as well as possess hepatoprotective and immunomodulatory activities. These health benefits derive primarily from the concentration and properties of those active compounds present in the mung bean. Vitexin and isovitexin are identified as the major polyphenols, and peptides containing hydrophobic amino acid residues with small molecular weight show higher bioactivity in the mung bean. Considering the recent surge in interest in the use of grain legumes, we hope this review will provide a blueprint to better utilize the mung bean in food products to improve human nutrition and further encourage advancement in this field.