Potential protective effects of sodium butyrate on glycinin-induced oxidative stress, inflammatory response, and growth inhibition in Cyprinus carpio.

Investigated mitigating effects of sodium butyrate (SB) on the inflammatory response, oxidative stress, and growth inhibition of common carp (Cyprinus carpio) (2.94 ± 0.2 g) are caused by glycinin. Six isonitrogenous and isoenergetic diets were prepared, in which the basal diet was the control diet and the Gly group diet contained 80 g/kg glycinin, while the remaining 4 diets were supplemented with 0.75, 1.50, 2.25, and 3.00 g/kg SB, respectively. The feeding trial lasted for 8 weeks, and the results indicated that supplementing the diet with 1.50-2.25 g/kg of SB significantly improved feed efficiency and alleviated the growth inhibition induced by glycinin. Hepatopancreas and intestinal protease activities and the content of muscle crude protein were significantly decreased by dietary glycinin, but supplement 1.50-2.25 g/kg SB partially reversed this result. SB (1.50-2.25 g/kg) increased the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the hepatopancreas and reduced the activities of AST and ALT in the serum. Glycinin significantly reduced immune and antioxidant enzyme activities, whereas 1.50-2.25 g/kg SB reversed these adverse effects. Furthermore, compared with the Gly group, supplement 1.50-2.25 g/kg SB eminently up-regulated the TGF-ß and IL-10 mRNA, and down-regulated the IL-1ß, TNF-α, and NF-κB mRNA in hepatopancreas, mid-intestine (MI), and distal intestine (DI). Meanwhile, supplement 1.50-2.25 g/kg SB activated the Keap1-Nrf2-ARE signaling pathway and upregulate CAT, SOD, and HO-1 mRNA expression in hepatopancreas, MI, and DI. Summarily, glycinin induced inflammatory response, and oxidative stress of common carp ultimately decreased the digestive function and growth performance. SB partially mitigated these adverse effects by activating the Keap1-Nrf2-ARE signaling pathway and inhibiting the NF-κB signaling pathway.

Biomacromolecule assembly of soy glycinin-potato starch complexes: Focus on structure, function, and applications.

The effect of the cross-linking mechanism and functional properties of soy glycinin (11S)-potato starch (PS) complexes was investigated in this study. The results showed that the binding effecting and spatial network structure of 11S-PS complexes via heated-induced cross-linking were adjusted by biopolymer ratios. In particular, 11S-PS complexes with the biopolymer ratios of 2:15, had a strongest intermolecular interaction through hydrogen bonds and hydrophobic force. Moreover, 11S-PS complexes at the biopolymer ratios of 2:15 exhibited a finer three-dimensional network structure, which was used as film-forming solution to enhance the barrier performance and mitigate the exposure to the environment. In addition, the 11S-PS complexes coating was effective in moderating the loss of nutrients, thereby extending their storage life in truss tomato preservation experiments. This study provides helpful to insights into the cross-linking mechanism of the 11S-PS complexes and the potential application of food-grade biopolymer composite coatings in food preservation.

The protective role of vitamin C on intestinal damage induced by high-dose glycinin in juvenile Rhynchocypris lagowskii Dybowski.

This study was to evaluate the mitigative effects of vitamin C (VC) on growth inhibition and intestinal damage induced by glycinin in juvenile Rhynchocypris lagowskii Dybowski. 270 healthy juvenile Rhynchocypris lagowskii Dybowski (4.65 ± 0.04 g) were randomly divided into 3 treatments, and fed with control diet, 80 g/kg glycinin diet and 80 g/kg glycinin+200 mg/kg VC diet respectively for 8 weeks. The results showed that glycinin significantly decreased the weight gain rate, specific growth rate, protein efficiency rate, feed efficiency rate and feeding rate of fish compared with the control group (P < 0.05), while VC supplementation improved the growth performance and feed utilization efficiency, and reached a level similar to the control group. Similarly, VC significantly increased the crude protein content of muscle and whole-body, and hepatopancreas and intestinal protease activities of fish fed with glycinin diet (P < 0.05). The distal intestine of fish in glycinin group showed typical damage characteristics, including breakage and atrophy of intestinal mucosal fold, and increased intestinal mucosal permeability. However, fish fed the glycinin + VC diet showed an unimpaired normal intestinal morphology. Usefully, VC supplementation could also restore impaired immune function and antioxidant capacity. VC down-regulated the mRNA levels of pro-inflammatory cytokines TNF-α and IL-1ß, and up-regulated the mRNA levels of anti-inflammatory cytokines IL-10 and TGF-ß in the distal intestine of fish fed with glycinin. Furthermore, glycinin exposure could reduce the mRNA levels of HO-1, CAT and GPx by inhibiting the activation of Nrf2-Keap1 signaling pathway, while VC supplementation reversed this phenomenon and maintained the homeostasis of antioxidant defense system. Concluded, glycinin causes growth inhibition, digestive dysfunction and intestinal damage of Rhynchocypris lagowskii Dybowski, while sufficient VC intake is beneficial for fish to resist the adverse effects of glycinin.

The preparation of soy glycinin/sugar beet pectin complex network gels catalyzed by laccase under weakly acidic conditions.

BACKGROUND: Traditional soy protein gel products such as tofu, formed from calcium sulfate or magnesium chloride, have poor textural properties and water retention capacity. Soy glycinin (SG) is the main component affecting the gelation of soy protein and can be cross-linked with polysaccharides, such as sugar beet pectin (SBP), and can be modified by changing system factors (e.g., pH) to improve the gel's properties. Soy glycinin/sugar beet pectin (SG/SBP) complex double network gels were prepared under weakly acidic conditions using laccase cross-linking and heat treatment. The structural changes in SG and the properties of complex gels were investigated. RESULTS: Soy glycinin exposed more hydrophobic groups and free sulfhydryl groups at pH 5.0. Under the action of laccase cross-linking, SBP could promote the unfolding of SG tertiary structures. The SG/SBP complex gels contained 46.77% ß-fold content and had good gelling properties in terms of hardness 290.86 g, adhesiveness 26.87, and springiness 96.70 mm at pH 5.0. The T22 relaxation time had the highest peak, and magnetic resonance imaging (MRI) showed that the gel had even water distribution. Scanning electron microscopy (SEM) and confocal scanning laser microscopy (CLSM) indicated that the SG/SBP complex network structure was uniform, and the pore walls were thicker and contained filamentous structures. CONCLUSION: Soy glycinin/ sugar beet pectin complex network gels have good water-holding, rheological, and textural properties at pH 5.0. The properties of soy protein gels can be improved by binding to polysaccharides, with laccase cross-linked, and adjusting the pH of the solution. © 2022 Society of Chemical Industry.

Taurine can improve intestinal function and integrity in juvenile Rhynchocypris lagowskii Dybowski fed high-dose glycinin.

The present study evaluated the protective effect and the regulatory mechanism of taurine on growth inhibition and intestinal damage induced by glycinin in juvenile Rhynchocypris lagowskii Dybowski. The control diets had no glycinin and taurine, the glycinin diets contained only 80 g/kg glycinin, and the glycinin + taurine diets contained 80 g/kg glycinin+10 g/kg taurine. Juvenile Rhynchocypris lagowskii Dybowski (4.65 ± 0.03 g/tail) were respectively fed with these 3 diets for 8 weeks. The results showed that glycinin significantly decreased the final body weight, weight gain rate, specific growth rate, protein efficiency rate, feed efficiency rate and feeding rate of fish compared with the control group (P < 0.05). While taurine supplementation improved the growth performance and feed efficiency, but final body weight, weight gain rate, specific growth rate of the glycinin + taurine group were still significantly lower than the control group (P < 0.05). Compared with the glycinin group, taurine supplementation significantly increased whole-body and muscle crude protein content, and hepatopancreas and intestinal protease activities (P < 0.05). Distal intestinal villous dysplasia and mucosal damage, and increased intestinal mucosal permeability were observed in the glycinin group, while taurine supplementation alleviated these adverse effects. Usefully, taurine supplementation could also partially restore the impaired immune function and antioxidant capacity of fish fed glycinin diets. Compared with the glycinin group, taurine supplementation down-regulated pro-inflammatory cytokines TNF-α and IL-1ß mRNA levels, and up-regulated anti-inflammatory cytokines IL-10 and TGF-ß mRNA levels. Furthermore, taurine partially reversed the reduction of antioxidant genes Nrf2、HO-1, CAT and GPx mRNA levels in distal intestine induced by glycinin. Concluded, 80 g/kg glycinin led to intestinal damage, digestive dysfunction and increased intestinal mucosal permeability in juvenile Rhynchocypris lagowskii Dybowski, and these adverse effects were ultimately manifested in growth inhibition. But taurine supplementation could partially mitigate the negative effects induced by glycinin.

Influence of mild oxidation induced through DBD-plasma treatment on the structure and gelling properties of glycinin.

The effects of dielectric-barrier discharge (DBD) plasma treatment (20 s to 120 s treatment time with 40 kV, 12 kHz) induced mild oxidation on the gelling properties, and related structural changes of glycinin were investigated. The gelling ability of glycinin was improved by the mild oxidation induced by the plasma treatment. Treated glycinin gels exhibited a continuous and uniform network microstructure. Samples treated for 120 s had a 2.07-, 3.99- and 2.03-fold increase in hardness, chewiness, and resilience compared to the 20 s treated samples. Structural analyses showed that primary and secondary structures of glycinin were unaffected. The tertiary structure was shifted, accompanied by a decrease in free sulfhydryl (-SH) content. At the same time, carbonyl content and average particle diameter were increased by DBD treatment. The DBD treatment facilitated the generation/exchange of intermolecular disulfide bonds and enhanced gelling properties of glycinin. It is concluded that controlled plasma-induced protein oxidation can improve protein functionality.

Oxidation induced by dielectric barrier discharge (DBD) plasma treatment reduces IgG/IgE binding capacity and improves the functionality of glycinin.

The effect of dielectric barrier discharge (DBD) plasma treatment times from 2 to 5 min at 40 kV on IgG/IgE binding capacity and functionality of soybean glycinin was examined. A substantial reduction in the binding capacity (91.64% for IgG and 81.49% for IgE) was obtained after 5 min of plasma treatment, as determined by western-blot and ELISA analyses. Further studies demonstrated that the elimination of antigenicity and allergenicity of glycinin was directly related to plasma-induced structural changes on two aspects. A conformational alteration caused by oxidation of peptide bond amino groups, accompanied with an oxidation of Trp, Tyr, and Phe amino acid residues, which was confirmed by surface hydrophobicity, multi-spectroscopic analysis, and amino acid analysis. The cleavage of polypeptide chains inevitably partially diminished the linear epitopes, resulting in a primary decline in IgG/IgE binding capacity. Additionally, an increase in the solubility from 10.78 ± 0.35 to 65.96 ± 1.86% and significant increase in the emulsifying ability from 21.08 ± 2.64 to 160.29 ± 4.12 m2/g were observed after treatment of the plasma for 2 min. The present results confirm the potential use of DBD for the production of hypoallergenic soy protein-based products and improving their technical functions such as solubility and emulsifying ability.

Sodium butyrate can improve intestinal integrity and immunity in juvenile Chinese mitten crab (Eriocheir sinensis) fed glycinin.

Butyrate is a fermentation byproduct of gut microbiota and is susceptible to chronic oxidative stress. This study investigates the mitigative effects of sodium butyrate (SBT) on growth inhibition and intestinal damage induced by glycinin in juvenile Chinese mitten crab (Eriocheir sinensis). All four experimental diets containing 80 g/kg glycinin were formulated with 0, 10, 20 and 40 g/kg SBT respectively. There was no glycinin or SBT in the control diet. Juvenile crabs (0.33 ± 0.01g) were respectively fed with these five diets for eight weeks. The diets with 10 and 20 g/kg SBT significantly improved the survival and weight gain of the crabs compared with those in the 0 g/kg SBT group, and showed no difference with the control group. The crabs fed diets containing glycinin without SBT had lower glutathione and glutathione peroxidase activities but higher malondialdehyde in the intestine than those in the control group. Moreover, dietary glycinin decreased the lysozyme and phenoloxidase activities and improved the level of histamine in the intestine compared with the control group, while the supplementation of SBT counteracted these negative effects. The addition of SBT could also restore the impaired immunity and morphological structure of the intestine. Dietary SBT could increase the mRNA expression of antimicrobial peptides genes (anti-lipopolysaccharide factor 1 and 2) and decrease the content of pro-inflammatory factor TNF-α. The SBT could restore the intestinal microbial community disorganized by glycinin. The abundance of pathogenic bacteria (Aeromonas, Vibrio and Pseudomonas) decreased significantly and the potential probiotic bacteria (Bacillus, Lactobacillus, Chitinibacter and Dysgonomonas) increased significantly in the 10 g/kg SBT group. This study suggests that sodium butyrate supplementation can mitigate the negative effects induced by glycinin such as growth inhibition, intestinal inflammation and reduction of beneficial flora in the gut.

Soy glycinin-soyasaponin mixtures at oil-water interface: Interfacial behavior and O/W emulsion stability.

Soy glycinin (11S) was mixed with soyasaponin (Ssa) to elucidate the mechanism(s) involved in the stabilization of emulsions by mixed systems based on dynamic interfacial tension and dilatational rheology at the oil-water interface. The short/long-term properties of oil-in-water emulsions stabilized by 11S-Ssa mixtures included droplet-size distribution, droplet ζ-potential, microstructure, and Turbiscan stability index. The combination of Ssa (0.05%) with 11S significantly affected the interfacial dilatational and emulsion properties although the interfacial properties were still dominated by the protein. Higher concentrations (0.1% and 0.2%) of Ssa combined with 11S synergistically decreased the interfacial tension, which was attributed to the interaction between 11S and Ssa. Using high Ssa concentrations (0.25%-0.5%) enhanced the long-term stability of emulsions (in response to external deformations) after 42 d. These results will aid the basic understanding of protein-Ssa interfacial adsorption during emulsion formation and can help prepare natural food additives for designing emulsions.

Dietary supplementation of soybean glycinin can alter the growth, carcass traits, blood biochemical indices, and meat quality of broilers.

The current research aimed to estimate the effect of dietary supplementation with glycinin isolated from soybeans on the growth performance, carcass traits, and selected blood metabolites of broiler chicks. A total of 200 1-wk-old broiler chicks were administered diets without glycinin (control treatment) or diets supplemented with 3 concentrations of soy glycinin (0.5, 1.0, or 1.5 g/kg of feed) for 6 wk. At the end of the feeding period, body weight was significantly higher in broiler chicks with glycinin supplementation (P < 0.05 or 0.01). The best values for body weight and body weight gain were recorded in the groups fed diets supplemented with 0.5 and 1.0 g glycinin/kg feed. Feed conversion was significantly (P < 0.05) improved in broilers in the glycinin-supplemented groups during the 1 to 6 and 3 to 6 wk growth periods. The highest value of breast yield was observed in broiler chicks supplemented with glycinin at a concentration of 1.0 g/kg of feed. Water-holding capacity increased with increasing concentrations of glycinin in the feed, up to 1.0%. Serum creatinine and urea concentrations decreased gradually (P < 0.01) as the concentration of glycinin in the feed increased. Broiler chicks receiving increasing concentrations of glycinin exhibited significantly (P < 0.01) lower levels of serum triglycerides, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol. All meat samples from broiler chicks supplemented with glycinin had significantly higher catalase activities. These data suggest that feeding broiler chicks diets supplemented with soy glycinin (0.5 to 1.5 g/kg of feed) can improve feed conversion, enhance body weight gain, and lower abdominal fat.

MHC II-PI3K/Akt/mTOR Signaling Pathway Regulates Intestinal Immune Response Induced by Soy Glycinin in Hybrid Grouper: Protective Effects of Sodium Butyrate.

Soy glycinin (11S) is involved in immune regulation. As an additive, sodium butyrate (SB) can relieve inflammation caused by 11S. To further delve into the mechanisms. A diet containing 50% fishmeal was the control group (FM group), and the experimental groups consisted of the FM group baseline plus 2% glycinin (GL group), 8% glycinin (GH group), and 8% glycinin + 0.13% sodium butyrate (GH-SB group). The specific growth ratio (SGR), feed utilization, and density of distal intestinal (DI) type II mucous cells were increased in the GL group. In the serum, IFN-γ was significantly upregulated in the GL group, and IgG and IL-1ß were upregulated in the GH group. IgG, IL-1ß, and TNF-α in the GH-SB group were significantly downregulated compared to those in the GH group. The mRNA levels of mTOR C1, mTOR C2, and Deptor were upregulated in the GL, GH, and GH-SB groups in the DI compared with those in the FM group, while the mRNA levels of mTOR C1 and Deptor in the GH group were higher than those in the GL and GH-SB groups. 4E-BP1, RICTOR, PRR5, MHC II, and CD4 were upregulated in the GH group. TSC1, mLST8, and NFY mRNA levels in the GL and GH-SB groups were upregulated compared with those in the FM and GH groups. Western blotting showed P-PI3KSer294/T-PI3K, P-AktSer473/T-Akt, and P-mTORSer2448/T-mTOR were upregulated in the GH group. Collectively, our results demonstrate that low-dose 11S could improve serum immune by secreting IFN-γ. The overexpression of IgG and IL-1ß is the reason that high-dose 11S reduces serum immune function, and supplementing SB can suppress this overexpression. Low-dose 11S can block the relationship between PI3K and mTOR C2. It can also inhibit the expression of 4E-BP1 through mTOR C1. High-dose 11S upregulates 4E-BP2 through mTOR C1, aggravating intestinal inflammation. SB could relieve inflammation by blocking PI3K/mTOR C2 and inhibiting 4E-BP2. Generally speaking, the hybrid grouper obtained different serum and DI immune responses under different doses of 11S, and these responses were ultimately manifested in growth performance. SB can effectively enhance serum immunity and relieve intestinal inflammation caused by high dose 11S.

Effects of glycinin and ß-conglycinin on growth performance and intestinal health in juvenile Chinese mitten crabs (Eriocheir sinensis).

This study investigates the effects of two soybean antigens (glycinin and ß-conglycinin) as an antinutritional substance in the diet on the growth, digestive ability, intestinal health and microbiota of juvenile Chinese mitten crabs (Eriocheir sinensis). The isonitrogenous and isolipidic diets contained two soybean antigens at two levels each (70 and 140 g/kg ß-conglycinin, 80 and 160 g/kg glycinin) and a control diet without ß-conglycinin or glycinin supplementation, and were used respectively to feed juvenile E. sinensis for seven weeks. Dietary inclusion of either glycinin or ß-conglycinin significantly reduced crab survival and weight gain. The crabs fed diets containing soybean antigens had higher malondialdehyde concentrations and lower catalase activities in the intestine than those in the control. The activities of trypsin and amylase in the intestine were suppressed by dietary ß-conglycinin and glycinin. Dietary glycinin or ß-conglycinin impaired the immunity and morphological structure of intestine, especially the peritrophic membrane. The mRNA expression of constitutive and inducible immune responsive genes (lipopolysaccharide-induced TNF-α factor and interleukin-2 enhancer-binding factor 2) increased while the mRNA expression of the main genes related to the structural integrity peritrophic membrane (peritrophin-like gene and peritrophic 2) significantly decreased in the groups with soybean antigen addition. Soybean antigen could also change the intestinal microbial community. The abundance of pathogenic bacteria (Ochrobactrum, Burkholderia and Pseudomonas) increased significantly in both soybean antigen groups. Although pathogenic bacteria Vibrio were up-regulated in the glycinin group, the abundance of Dysgonomonas that degraded lignocellulose and ameliorated the gut environment decreased in the glycinin group. This study indicates that existence of soybean antigens (glycinin or ß-conglycinin) could induce gut inflammation, reshape the community of gut microbiota, and cause digestive dysfunction, ultimately leading to impaired growth in crabs.

Molecular Mechanism for Improving Emulsification Efficiency of Soy Glycinin by Glycation with Soy Soluble Polysaccharide.

Glycation with carbohydrates has been considered to be an effective strategy to improve the emulsifying properties of plant storage globulins, but the knowledge is inconsistent and even contradictory. This work reported that the glycation with soy soluble polysaccharide (SSPS) progressively improved the emulsification efficiency of soy glycinin (SG) in a degree-of-glycation (DG)-dependent manner. The glycation occurred in both the acidic (A) and basic (B) polypeptides to a similar extent. The physicochemical and structural properties of glycated SG samples with different DG values of 0-35% were characterized. The emulsifying properties of unglycated and glycated SG were performed on the emulsions at an oil fraction of 0.3 and a protein concentration in the aqueous phase, produced using microfluidization as the emusification process. The glycation with increasing the DG led to a progressive decrease in solubility and surface hydrophobicity but remarkably increased the magnitude of ζ-potential. Dynamic latter scattering and spectroscopic results showed that the glycation resulted in a gradual dissociation of the 11S-form SG at the quaternary level (into different [AB] subunits), in a DG-dependent way, while their tertiary ([AB] subunits) and secondary structure were slightly affected. Besides the emulsification efficiency, the glycation progressively accelerated the droplet flocculation and facilitated the adsorption of the proteins at the interface and formation of bridged emulsions. The results demonstrated that the improvement of the emulsification efficiency of SG by the glycation with SSPS was largely attributed to the enhanced conformation flexibility at the [AB] subunit level as well as facilitated formation of bridged emulsions. It was also confirmed that once the glycated SG adsorbed at the interface, it would readily dissociated into subunits; the dissociated [AB] subunits exhibited an outstanding Pickering stabilization. The findings would be of importance for providing new knowledge about the molecular mechanism for the modification of emulsifying properties of oligomeric globulins by the glycation with polysaccharides.

The α' subunit of ß-conglycinin and various glycinin subunits of soy are not required to modulate hepatic lipid metabolism in rats.

PURPOSE: This study examined the effect of soy proteins with depletion of different subunits of the two major storage proteins, ß-conglycinin and glycinin, on hepatic lipids and proteins involved in lipid metabolism in rats, since the bioactive component of soy responsible for lipid-lowering is unclear. METHODS: Weanling Sprague Dawley rats were fed diets containing either 20% casein protein in the absence (casein) or presence (casein + ISF) of isoflavones or 20% alcohol-washed soy protein isolate (SPI) or 20% soy protein concentrates derived from a conventional (Haro) or 2 soybean lines lacking the α' subunit of ß-conglycinin and the A1-3 (1TF) or A1-5 (1a) subunits of glycinin. After 8 weeks, the rats were necropsied and liver proteins and lipids were extracted and analysed. RESULTS: The results showed that soy protein diets reduced lipid droplet accumulation and content in the liver compared to casein diets. The soy protein diets also decreased the level of hepatic mature SREBP-1 and FAS in males, with significant decreases in diets 1TF and 1a compared to the casein diets. The effect of the soy protein diets on female hepatic mature SREBP-1, FAS, and HMGCR was confounded since casein + ISF decreased these levels compared to casein alone perhaps muting the decrease by soy protein. A reduction in both phosphorylated and total STAT3 in female livers by ISF may account for the gender difference in mechanism in the regulation and protein expression of the lipid modulators. CONCLUSIONS: Overall, soy protein deficient in the α' subunit of ß-conglycinin and A1-5 subunits of glycinin maintain similar hypolipidemic function compared to the conventional soy protein. The exact bioactive component(s) warrant identification.

Effects of ultrasound pre-treatment on the structure of ß-conglycinin and glycinin and the antioxidant activity of their hydrolysates.

The effect of power, time and temperature of ultrasound on the structure of ß-conglycinin (7S) and glycinin (11S), and on the antioxidant activity of their hydrolysates were investigated. All ultrasound treated 7S and 11S fractions showed an increase in the α-helix and ß-turn proportions, and a decrease in ß-sheet and random coil proportions. The polarity of 7S and 11S microenvironment increased after ultrasound treatment. Ultrasound treatment significantly increased the reduction capacity and iron chelating capacity of 7S and 11S hydrolysates. The degree of hydrolysis and free SH groups of 7S and 11S hydrolysates increased after ultrasound pre-treatment. The relative content of high molecular weight peptides reduced, and the relative content of low molecular weight peptides increased in ultrasound treated 7S and 11S hydrolysates. The ultrasonication exposed certain groups of 7S and 11S fractions, improved contact with enzymes, and increased the content of highly active soybean antioxidant peptides.