Wet-type grinder-treated okara modulates gut microbiota composition and attenuates obesity in high-fat-fed mice.

Wet-type grinder (WG) is a nanofiber technology used to atomize dietary fiber-rich materials. WG-treated okara (WGO) exhibits high dispersion and viscosity similar to those of viscous soluble dietary fibers. Here, we studied the effect of WGO supplementation on obesity and gut microbiota composition in high-fat diet (HFD)-fed mice. WGO intake suppressed body weight gain and fat accumulation, improved glucose tolerance, lowered cholesterol levels, and prevented HFD-induced decrease in muscle mass. WGO supplementation also led to cecum enlargement, lower pH, and higher butyrate production. The bacterial 16S ribosomal RNA genes (16S rDNA) were sequenced to determine the gut microbiota composition of the fecal samples. Sequencing of bacterial 16S rDNA revealed that WGO treatment increased the abundance of butyrate producer Ruminococcus and reduced the abundances of Rikenellaceae, Streptococcaceae, and Prevotellaceae, which are related to metabolic diseases. Metabolomics analysis of the plasma of WGO- and cellulose-treated mice were conducted using ultra-high-performance liquid chromatography-mass spectrometry. Metabolic pathway analysis revealed that the primary bile acid biosynthesis pathway was significantly positively regulated by WGO intake instead of cellulose. These results demonstrate that WG is useful for improving functional properties of okara to prevent metabolic syndromes, including obesity, diabetes, and dyslipidemia.

Wet Grinder-Treated Okara Improved Both Mechanical Properties and Intermolecular Forces of Soybean Protein Isolate Gels.

The application of okara treated by a wet-type grinder (WG) is discussed in this paper. We examined the effect of WG-treated okara on the mechanical properties and intermolecular forces in soybean protein isolate (SPI) gels. SPI gels were prepared with varying amounts of WG-treated okara, and compression tests were performed. Protein solubility was also examined by homogenizing the gel in four different solutions (S1, 0.6 M sodium chloride (NaCl); S2, 0.6 M NaCl and 1.5 M urea; S3, 0.6 M NaCl and 8.0 M urea; and S4, 1.0 M sodium hydroxide). The gel with WG-treated okara had higher breaking stress but not breaking strain. In contrast, the protein solubility in S3 was lower than those of the gel without okara or with WG-untreated okara. A negative correlation (R2 = 0.86) was observed between breaking stress and protein solubility in S3. These results suggest that WG-treated okara enhanced the hydrophobic interactions of SPI gels because protein solubilization by S3 is caused by the differences in hydrophobic interactions.

Developing Soybean Protein Gel-Based Foods from Okara Using the Wet-Type Grinder Method.

Okara, a by-product of tofu or soymilk, is rich in dietary fibers (DFs) that are mostly insoluble. A wet-type grinder (WG) system was used to produce nanocellulose (NC). We hypothesized that the WG system would increase the dispersion performance and viscosity of okara. These properties of WG-treated okara improve the gel-forming ability of soybean proteins. Here, the suspensions of 2 wt% okara were treated with WG for different passages (1, 3, and 5 times). The particle size distribution (PSD) and viscosity of WG-treated okara decreased and increased, respectively, with different passages. The five-time WG-treated okara homogeneously dispersed in water after 24 h, whereas untreated okara did not. The breaking stress, strain, and water holding capacity of soybean protein isolate (SPI) gels increased upon the addition of WG-treated okara. This effect increased as the number of WG treatments increased. The breaking stress and strain of SPI gels to which different concentrations of the five-time WG-treated okara were added also increased with increasing concentrations of WG-treated okara. These results suggest that NC technology can improve the physicochemical properties of okara and are useful in the development of protein gel-based foods.

Improved effects of okara atomized by a water jet system on α-amylase inhibition and butyrate production by Roseburia intestinalis.

Improving the physicochemical properties of okara for various applications in foods is of great importance. Here, okara and microcrystalline cellulose (MCC) were atomized using a water jet (WJ) system. The WJ-treated okara and MCC dispersed homogeneously in water, and their median sizes in particle size distribution were 6.6 µm and 9.5 µm, respectively. The dispersions of WJ-treated okara and MCC showed high apparent viscosity and shear thinning behavior. Moreover, the inhibition of α-amylase activities by WJ-treated okara was more effective than that by untreated MCC and cellulose. Furthermore, the production of short-chain fatty acids by 32 dominant species of human gut microbes was determined. An increase in butyrate production by Roseburia intestinalis was observed in the presence of WJ-treated okara, but not in untreated okara or WJ-treated MCC. These results demonstrate that WJ system can be used on okara to increase inhibited α-amylase activities and butyrate production by gut microbiota.

Effect of dietary cellulose nanofiber and exercise on obesity and gut microbiota in mice fed a high-fat-diet.

Cellulose nanofiber (CN) consumption with exercise could be a potential strategy to control obesity. Here, we studied the effects of CN supplementation and voluntary exercise on obesity and gut microbiota in high-fat diet (HFD)-fed mice. Consumption of CN increased voluntary wheel running activity. CN intake and exercise together suppressed the increase in body weight and fat mass, and improved glucose tolerance. The fecal gut microbiota was analyzed by sequencing 16S ribosomal RNA genes. Principal component analysis revealed a shift in the microbiota composition resulting from exercise, but not from CN supplementation. Erysipelotrichaceae and Rikenellaceae decreased with exercise. Exercise also increased Ruminococcaceae, whereas exercise and CN intake together increased Eubacteriaceae. These two families are butyrate producers. Exercise increased the amount of acetate in the cecum. These results suggest that CN consumption improves exercise performance and exerts anti-obesity effects by modulating the balance of the gut microbiota.

Inhibitory effects of dietary soy isoflavone and gut microbiota on contact hypersensitivity in mice.

Soy isoflavones (SIs) are abundant in soybeans and have inhibitory effects on contact hypersensitivity (CHS), which is often used as a mouse model for allergic contact dermatitis (ACD); however, their therapeutic mechanisms remain unknown. We studied the suppressive activity of dietary SI and gut microbiota on dinitrofluorobenzene (DNFB)-induced CHS. Low-dose SI diets alleviated DNFB-induced ear swelling and oedema and decreased infiltration of Gr-1-positive cells into ear tissue. In addition, dietary SIs also decreased interleukin-1ß and chemokine (C-X-C motif) ligand 1 production in ear tissue compared to controls. Furthermore, ciprofloxacin and metronidazole treatments blocked the suppressive activity of dietary SIs on CHS, whereas vancomycin treatment had a marginal effect. These antibiotic treatments differed in their effects on the gut microbiota composition. These results demonstrated that consumption of physiologically relevant doses of SIs reduced CHS symptoms, and suggested that the gut microbiota influenced their suppressive activities on CHS.

Diets containing pomegranate polyphenol and soy isoflavone attenuate contact hypersensitivity in mice.

Contact hypersensitivity (CHS) is frequently used as an animal model for human allergic contact dermatitis (ACD). Diets of pomegranate polyphenols (PPs) or soy isoflavones (SIs) each alleviated CHS symptoms; however, the effect of diets containing a mixture of PPs and SIs on CHS is unclear. We investigated the CHS-inhibitory effects of diets supplemented with a mixture of PPs and SIs at human physiologically relevant doses. Consuming the mixture of PPs and SIs attenuated ear swelling and reduced infiltration of Gr-1-positive cells. Ear swelling decreased in the PP and SI-treated mice compared to the SI-treated mice. The auricle tissues of the PP and SI-fed mice exhibited decreased production of CXCL2 and MCP-5 compared to the SI- and PP-treated mice, respectively. These results suggest that dietary supplementation with a mixture of PPs and SIs may have ACD-preventive effects and may prove more beneficial than supplementation with PPs or SIs alone.

Impact of soymilk consumption on 2,4-dinitrofluorobenzene-induced contact hypersensitivity and gut microbiota in mice.

Soymilk is rich in phytochemicals such as soy isoflavones (SIs) and soyasaponins (SSs). Dietary SIs and SSs display inhibitory effects on contact hypersensitivity (CHS), which was reported in a mouse model for allergic contact dermatitis (ACD); however, the beneficial effects of soymilk consumption on CHS remain unknown. Here, we studied the effects of drinking soymilk on CHS and gut microbiota. Soymilk consumption attenuated ear oedema and swelling, decreased the infiltration of Gr-1-positive cells into ear tissues, and reduced the production of chemokine (C-X-C motif) ligand 2 and triggering receptor expressed on myeloid cells-1 in ear tissues. The analysis of bacterial 16S ribosomal RNA gene sequences indicated that CHS caused changes in the gut microbiota structure and that consuming soymilk reduced these changes. These results suggest that soymilk consumption may be of therapeutic value for patients with ACD and may help control the balance of intestinal microbiota.

Inhibitory effects of dietary soyasaponin on 2,4-dinitrofluorobenzene-induced contact hypersensitivity in mice.

Soyasaponins (SSs) abundant in soybean have anti-inflammatory activities; however, their therapeutic effects on allergic contact dermatitis (ACD) remain unknown. To assess the effects of SS-enriched diets on ACD, we used a mouse model of contact hypersensitivity (CHS). Mice were fed low-dose or high-dose SS-containing diets for 3 weeks prior to CHS induction with 2,4-dinitrofluorobenzene (DNFB). The low-dose SS diet attenuated DNFB-induced ear swelling and tissue oedema, and reduced the number of infiltrating Gr-1-positive myeloid cells. Low-dose, but not high-dose, SSs decreased chemokine (C-X-C motif) ligand 2 (CXCL2) and triggering receptor expressed on myeloid cells (TREM)-1 production in ear tissues, compared to a control. Taxonomic 16S rRNA analysis revealed significant alterations in faecal microbiota caused by CHS, which were reversed by low-dose SSs. The low-dose SS and non-CHS groups clustered together, while the high-dose SS group split between CHS and non-CHS clusters. Our results demonstrated that low-dose SSs alleviated CHS symptoms by attenuating inflammation and improving the intestinal microbiota composition, suggesting that dietary SSs may have beneficial effects on ACD.

The inhibitory effect of soybean and soybean isoflavone diets on 2,4-dinitrofluorobenzene-induced contact hypersensitivity in mice.

Murine contact hypersensitivity (CHS) is one of the most frequently used animal models of human allergic contact dermatitis. We investigated the inhibitory effects of soybean and soy isoflavone (SI) diets on 2,4-dinitrofluorobenzene- (DNFB) induced CHS in mice. The DNFB-induced ear swelling was inhibited in the soy- and SI-treated groups. Histopathological investigations revealed that oral feeding of soybean and SI attenuated ear tissue edema and reduced the number of Gr-1(+) cell infiltrations into ear tissues. DNA microarray analysis showed that the expression of Ccl24, Xcl1, Ifng, and Ccl17 in the ear tissues was lower in the soy-treated mice than in the positive controls. In addition, CCL24 mRNA and protein expression in the ear tissues were more highly suppressed in the soy- and SI-treated groups. These results suggest that soybean and SI consumption downregulated the gene and protein expression of CCL24, thereby affording protection against CHS in mice.

Inhibitory effect of ellagitannin metabolites on IgE-mediated allergic responses in RBL-2H3 cells.

The effects of four ellagitannin metabolites (M1-M4) and ellagic acid on immunoglobulin E-mediated allergic responses in rat basophilic leukemia-2H3 cells were investigated. M1-M4 inhibited the antigen-induced degranulation and secretion of interleukin-4 and tumor necrosis factor-α, but ellagic acid only slightly did so under the same experimental conditions. M1 inhibited the activation of the mitogen-activated protein kinases in antigen-stimulated cells.

Exercise-independent wheat-induced anaphylaxis caused by ω-5 gliadin in mice.

BACKGROUND: ω-5 Gliadin is known as a major allergen in wheat-dependent exercise-induced anaphylaxis. The characteristics that make ω-5 gliadin an allergen remain unclear. METHODS: Mice were sensitized by means of intraperitoneal injection of gliadin fractions together with the adjuvant alum. Anaphylactic responses were assessed by measuring body temperature and voluntary physical activity. Specific IgE levels in mouse serum were evaluated by ELISA. After oral administration of proteins to mice, concentrations of administered proteins in their portal blood were also analyzed by competitive inhibition ELISA. RESULTS: Oral administration of ω-5 gliadin evoked significant decreases in body temperature and physical activity of sensitized mice, whereas the gliadin fraction did not induce these effects at the same dose. These responses were exercise independent. ELISA analysis revealed that IgE antibodies from sensitized mice react to ω-5 gliadin with great efficacy. After oral administration of either the gliadin fraction or ω-5 gliadin, blood levels of ω-5 gliadin were much higher than those of the gliadin fraction. CONCLUSIONS: ω-5 Gliadin caused anaphylaxis in sensitized mice, whereas the gliadin fraction did not at the same dose. The anaphylactic response was exercise independent. It is likely that IgE of sensitized mice reacts strongly to ω-5 gliadin and that ω-5 gliadin is better absorbed from the gastrointestinal tract than other components of the gliadin fraction. These results indicated that ω-5 gliadin has prominent characteristics as an allergen and that exercise might be an indirect factor in anaphylaxis induction.

Impact of ω-5 gliadin on wheat-dependent exercise-induced anaphylaxis in mice.

The effects of ω-5 gliadin on wheat-dependent exercise-induced anaphylaxis (WDEIA) were investigated by using a mouse model. The gliadin fraction was prepared as a 70% ethanol-soluble solution, and ω-5 gliadin was purified by chromatography. Purified ω-5 gliadin was run on SDS-PAGE gel to reveal three bands with a molecular mass of 53-60 kDa and had the characteristic N-terminal sequence of ω-5 gliadin. The mice were sensitized to the gliadin fraction, and the anaphylactic response was assessed by measuring the body temperature and voluntary physical activity. An oral administration of ω-5 gliadin evoked a significant drop in both the body temperature and voluntary physical activity, similar to the effects of the whole gliadin fraction. ELISA and immunoblotting analyses revealed that the IgE expression from sensitized mice reacted most strongly to ω-5 gliadin. Taken together, these results indicate ω-5 gliadin to be a major allergen responsible for stimulating WDEIA in mice, with the characteristic potential for stimulating IgE production.

SmI2-promoted Reformatsky-type reaction and acylation of alkyl 1-chlorocyclopropanecarboxylates.

In the presence of HMPA in THF, highly stereoselective SmI(2)-promoted substitutions of alkyl 1-chlorocyclopropanecarboxylates 1 using various ketones, aldehydes (Reformatsky-type reaction), and acyl chlorides (acylation) proceeded to give trans-adducts (2 or 5) in good to high yield with excellent trans-stereoselectivity (trans-add/cis-add = > 99/1). The Reformatsky-type reaction of 1 with aldehydes and unsymmetrical ketones proceeded with moderate diastereoselectivity (re-face-adduct/si-face-adduct = 60/40-75/25).

Highly stereoselective radical carbonylations of gem-dihalocyclopropane derivatives with CO.

A couple of radical carbonylations of gem-dihalocyclopropanes 1 using CO and Bu3SnH (formylation) or Bu3Sn(CH2CH=CH2) (allylacylation) successfully proceeded to give trans and cis adducts (2 and 3) with good to excellent stereoselectivity (trans/cis = >99/1-75/25 or 17/83-1/99). The formylation of 2,3-cis-disubstituted 1,1-dihalocyclopropanes enhanced trans selectivity (trans/cis = >99/1-95/5), whereas both 2,3-cis-disubstituted and 2-monosubstituted 1,1-dihalocyclopropanes underwent allylacylation with nearly complete trans selectivity (trans/cis = >99/1). Inherently less reactive gem-dichloro- and bromochlorocyclopropanes than gem-dibromocyclopropanes served as favorable substrates. [reaction: see text].