Comparison of the Effects of Roasted and Boiled Red Kidney Beans ( Phaseolus vulgaris L.) on Glucose/Lipid Metabolism and Intestinal Immunity in a High‐Fat Diet‐Induced Murine Obesity Model

Non-starch polysaccharides from kidney beans: comprehensive insight into their extraction, structure and physicochemical and nutritional properties

Kidney beans (Phaseolus vulgaris L.) are an important legume source of carbohydrates, proteins, and bioactive molecules and thus have attracted increasing attention for their high nutritional value and sustainability. Non-starch polysaccharides (NSPs) in kidney beans account for a high proportion and have a significant impact on their biological functions. Herein, we critically update the information on kidney bean varieties and factors that influence the physicochemical properties of carbohydrates, proteins, and phenolic compounds. Furthermore, their extraction methods, structural characteristics, and health regulatory effects, such as the regulation of intestinal health and anti-obesity and anti-diabetic effects, are also summarized. This review will provide suggestions for further investigation of the structure of kidney bean NSPs, their relationships with biological functions, and the development of NSPs as novel plant carbohydrate resources.

Comparison of the effects of three forms of soluble dietary fiber on the production of IgA in BALB/cAJcl and BALB/cAJcl-nu/nu mice

BACKGROUND

Their ability to induce the production of IgA, especially in the intestine, is one of the health benefits of soluble dietary fibers (SDFs), but the mechanism involved is unclear.

OBJECTIVE

This study was designed to identify the relationship between the induction of IgA by SDFs and the cecal short-chain fatty acids (SCFAs) content, and to evaluate the importance of T cell-independent IgA production for SDF-induced IgA production.

METHODS

We compared the SDFs fructooligosaccharides (FO), indigestible glucan (IG), and polydextrose (PD). Male BALB/cAJcl mice or T cell-deficient BALB/cAJcl-nu/nu (nude) mice were fed diets supplemented with one SDF (3% w/w) for 10 weeks and we measured IgA content in their feces, plasma, lung, and submandibular gland.

RESULTS

In BALB/cAJcl mice, the consumption of all three SDF diets induced fecal IgA production, but the response was stronger in the IG and PD groups than in the FO group. The IgA concentration of the plasma and lung were also higher in the FO and PD groups, and these groups showed significantly higher cecal acetic and n-butyric acid content. In contrast, in nude mice, the induction of IgA production was identified only in fecal samples of mice fed the three SDF diets, even though there were significant increases in cecal SCFAs content.

CONCLUSIONS

The induction of IgA production by SDFs is occurred T cell-independently in the intestine, but that in the plasma, lung, and submandibular gland is T cell-dependent. SCFAs generated in the large intestine might influence the systemic immune system, but there is no clear relationship between the generation of SCFAs and intestinal IgA production in response to SDF consumption.

Kidney Bean Fermented Broth Alleviates Hyperlipidemic by Regulating Serum Metabolites and Gut Microbiota Composition

Hyperlipidemia with fat accumulation and weight gain causes metabolic diseases and endangers human body health easily which is accompanied by metabolic abnormalities and intestinal flora disorders. In this study, the kidney bean fermented broth (KBF) was used in rats that were fed a high-fat diet to induce hyperlipidemia in order to subsequently analyse the serum metabolomics and gut microbiota modulatoration. The results show that the contents of the total polyphenols and total flavonoids in the KBF were up three and one times, while energy and carbohydrates decreased. In the HFD-induced hyperlipidemic model, body weight, organ weight, and the level of blood lipids (ALT, AST, TG, TC) were lower in rats treated with KBF than in the controls. Metabonomics indicate that there were significant differences in serum metabolomics between the KBF and the HFD. KBF could significantly improve the glycerophospholipids, taurine, and hypotaurine metabolism and amino acid metabolism of hyperlipidemic rats and then improve the symptoms of hypersterol and fat accumulation in rats. The relative abundance of beneficial bacteria increased while pathogenic bacteria decreased after the intervention of KBF. KBF ameliorates dyslipidemia of HFD-induced hyperlipidemic via modulating the blood metabolism and the intestinal microbiota. Collectively, these findings suggest that KBF could be developed as a functional food for anti-hyperlipidemia.

Daily Intake of a Phaseolus vulgaris L. Snack Bar Attenuates Hypertriglyceridemia and Improves Lipid Metabolism-Associated Plasma Proteins in Mexican Women: A Randomized Clinical Trial

Current efforts to prevent dyslipidemia are focused on the development of functional products as an alternative for hypertriglyceridemia management. This study assessed the metabolic effect of the daily consumption of a bean and oats snack bar (BOSB) on hypertriglyceridemia biomarkers among Mexican women. An 8-weeks randomized parallel clinical trial (ID: NCT0496694, https://clinicaltrials.gov/ct2/show/NCT04966494) was conducted with 26 hypertriglyceridemic women allocated to BOSB group (TG = 208.18 ± 56.97 mg/dL) and control group (TG = 182.28 ± 51.39 mg/dL). Only the BOSB group consumed 50 g of the product per day. Fasting blood samples were taken from women with an adherence ≥ 90%. A targeted proteomic analysis with plasma samples of control and BOSB groups were conducted using a human obesity antibody array kit and bioinformatic tools provided by the Ingenuity Pathways Analysis (IPA) software. Serum TG levels in the BOSB group decreased by 37.80% (132.04 ± 27.83 mg/dL) compared with the control group (178.87 ± 32.01 mg/dL); glucose levels decreased by 5.69% in the BOSB group (87.55 ± 3.36 mg/dL). A modest body weight (5%) reduction was also found. Forty proteins were differentially modulated by the BOSB consumption (fold change > 1.2). The proteomic analysis revealed the involvement of BOSB bioactives in prevention of monocytes recruitment and localized inflammatory response, inhibition of pre-adipocyte maturation and adipogenesis, inhibition of hepatic b-oxidation, and potential satiety regulation. These results are promising since the mere intervention with the BOSB reduced serum TG without diet restriction, giving insights for further research in prevention of hypertriglyceridemia.

Cooked Black Turtle Beans Ameliorate Insulin Resistance and Restore Gut Microbiota in C57BL/6J Mice on High-Fat Diets

Colored common beans are associated with health promoting and chronic disease prevention effects. Male C57BL/6J mice were fed high-fat (HF) diets supplemented with cooked black turtle beans (HFB) to prevent obesity related insulin resistance. Mice on both HF and HFB were obese compared to mice fed a low-fat (LF) diet. Plasma low density lipoprotein (LDL) and triglyceride concentrations of mice fed HFB diet were 28% and 36.6% lower than those on HF diet. Homeostatic model assessment of insulin resistance (HOMA-IR) index of mice fed HFB diet was 87% lower than that of mice fed HF diet. Diabetes related biomarkers, gastric inhibitory polypeptide (GIP), leptin, glucagon, and inflammatory cytokines interleukin 4 (IL-4) and IL-5, 10 and 12, IFN-g and TNF-α were significantly affected by HFB diet. Pparα, Cyp7a1 and Fasn were down-regulated by HFB diet while LDL-R, Srebp-2, Adipoq and Slc2a4 were up-regulated by HFB diet. The ratio of Firmicutes/Bacteroidetes (F/B) was also decreased 64.1% by HFB diet compared to HF diet. The results indicated that cooked black turtle bean consumption could ameliorate insulin resistance and lower plasma LDL in mice fed HF diet through glucose signaling pathway and JNK/c-Jun pathway. Meanwhile, cooked black turtle bean consumption restored the gut microbiome.

Prevention of the rise in plasma cholesterol and glucose levels by kaki-tannin and characterization of its bile acid binding capacity

BACKGROUND

Bile acid-binding agents, such as cholestyramine and colesevelam, improve both cholesterol and glucose metabolism. Kaki-tannin, a polymerized condensed tannin derived from persimmon (Diospyros kaki), has been shown to have bile acid-binding capacity and a hypocholesterolemic effect. However, its effects on glucose metabolism have not been well studied, and the binding selectivity of kaki-tannin to bile acid molecules has not been reported.

RESULTS

In vivo experiments using mice with high-fat diet-induced obesity showed that kaki-tannin intake (20 g kg^-1 of the diet) increased fecal bile acid excretion by 2.3-fold and prevented a rise in plasma cholesterol levels and fasting plasma glucose levels. Kaki-tannin also suppressed the development of impaired glucose tolerance. To characterize the bile acid-binding capacity of kaki-tannin, we investigated its capacity to bind to eight types of bile acid and cholesterol in vitro. Kaki-tannin showed strong capacity to bind to lithocholic acid (85.5%), which has one hydroxy group. It also showed moderate capacity to bind to bile acids with two hydroxy groups (53.3%), followed by those with three hydroxy groups (39.0%), but kaki-tannin did not show binding capacity to cholesterol. These results suggest that the binding capacity of kaki-tannin to bile acids tends to decrease as the number of hydroxy groups increases. Interestingly, the binding capacity of kaki-tannin correlated with that of cholestyramine (correlation coefficient: r = 0.900).

CONCLUSION

Our findings indicate that kaki-tannin binds preferentially to bile acids with fewer hydroxy groups and has beneficial effects on glucose metabolism as well as cholesterol metabolism. © 2020 Society of Chemical Industry.

Processing method modulates the effectiveness of black beans for lowering blood cholesterol in spontaneously hypertensive rats

BACKGROUND

Various foods are known to have beneficial effects on health when consumed whole; however, there is a trend towards preparing foods from processed ingredients, and it remains unclear whether the benefits of the whole food are retained. The purpose of this study was therefore to examine whether different processing techniques affect the lowering of cholesterol and the vascular effects of black beans (Phaseolus vulgaris L.).

RESULTS

Beans were prepared by overnight soaking and boiling - the standard method - and by micronization, extrusion, or dehulling and boiling, and they were then fine milled. Beans prepared by the standard method were also coarse milled. These five materials were incorporated into semi-purified diets (30% wt/wt) and fed to spontaneously hypertensive rats for 4 weeks. Body weight, blood pressure, and aorta morphology were unaltered by the diets. Fasting total cholesterol was significantly reduced in rats fed micronized beans compared with extruded beans (both fine-milled) or the bean-free diet, while boiling combined with coarse milling lowered low-density lipoprotein (LDL) cholesterol. The lack of cholesterol lowering in rats fed extruded bean compared to micronized was not explained by the amount or composition of dietary fiber or resistant starch. Differences in the polyphenolic profile as determined by high-performance liquid chromatography (HPLC) were also unable to explain the variations in cholesterol-lowering capacity.

CONCLUSION

The present study demonstrates that processing of black beans alters the health effects observed with the whole pulse, and suggests that products prepared with processed ingredients will need to be tested empirically to establish whether the biological effects are maintained in vivo. © 2020 Society of Chemical Industry.

Dietary resistant starch preserved through mild extrusion of grain alters fecal microbiome metabolism of dietary macronutrients while increasing immunoglobulin A in the cat

Dietary digestion-resistant starch (RS) provides health benefits to the host via gut microbiome-mediated metabolism. The degree to which cats manifest beneficial changes in response to RS intake was examined. Healthy cats (N = 36) were fed identically formulated foods processed under high (n = 17) or low (n = 19) shear extrusion conditions (low and high RS levels [LRS and HRS], respectively). Fecal samples collected after 3 and 6 weeks' feeding were assayed for stool firmness score, short-chain fatty acids, ammonia, and changes to the global metabolome and microbiome; fecal immunoglobulin A (IgA) was analyzed at week 6. Few differences were seen in proximate analyses of the foods; stool firmness scores did not differ. In cats consuming HRS food, concentrations of fecal butyrate and the straight chain:branched chain fatty acid ratio were significantly greater in feces at both weeks 3 and 6, while fecal ammonia was reduced at week 6 relative to feces from LRS-fed cats. Fecal IgA concentrations were significantly higher at week 6 with HRS food. RS consumption altered 47% of the fecal metabolome; RS-derived sugars and metabolites associated with greater gut health, including indoles and polyamines, increased in the cats consuming HRS food relative to those fed the LS food, while endocannabinoid N-acylethanolamines decreased. Consumption of HRS food increased concentrations of the ketone body 3-hydroxybutyrate in feces and elevated concentrations of reduced members of NADH-coupled redox congeners and NADH precursors. At the microbiome genus-level, 21% of operational taxonomic units were significantly different between food types; many involved taxa with known saccharolytic or proteolytic proclivities. Microbiome taxa richness and Shannon and Simpson alpha diversity were significantly higher in the HRS group at both weeks. These data show that feline consumption of grain-derived RS produces potentially beneficial shifts in microbiota-mediated metabolism and increases IgA production.

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.