Milk serum peptidomics revealed the age gelation of direct UHT milk.

Age gelation is undesirable for direct UHT (dUHT) milk, which is closely related to protein hydrolysis. However, little information is available for the role of serum peptides during the age gelation. In this study, the composition and protein morphology of serum phase were characterized by RP-HPLC, ICP-MS and TEM. The results showed significant increases in soluble proteins, free amino acids, calcium, and phosphorus from casein micelles, indicating protein hydrolysis and peptide release into the serum phase. 23,466 peptides derived from caseins and other proteins were identified in serum phase by peptidomics. The serum peptide profiles of age gelation milk changed dramatically. Peptide fingerprinting revealed that plasmin and cathepsin contributed to the protein hydrolysis during age gelation, with a significant increase in their activity observed. 23 characteristic peptides were ultimately selected as potential indicators for age gelation. These findings provide new insights into the age gelation of UHT milk.

New insights into the destabilization of fat globules in ultra-instantaneous UHT milk induced by added plasmin: Molecular mechanisms and the effect of membrane structure on plasmin action.

Residual plasmin activity in whole ultra-instantaneous UHT (UI-UHT) milk causes rapid fat rise during storage, seriously affecting consumers' purchase intentions. In this work, the molecular mechanisms underlying fat destabilization in whole UI-UHT milk by added plasmin were investigated based on the hydrolysis behavior of interfacial proteins. By using SDS-PAGE and peptidomic analysis, we found that the hydrolysis of interfacial proteins by plasmin led to a decrease in the amount and coverage of interfacial proteins and an increase in zeta-potential value, causing the flocculation and coalescence of fat globules. Moreover, the hydrolysis pattern varied in different categories of interfacial proteins by plasmin. In total, 125 peptides in all samples were identified. Plasmin tended to hydrolyze most major milk fat globule membrane (MFGM) proteins into protein fragments (>10 kDa) rather than peptides (<10 kDa). In contrast, peptides derived from caseins were more preferentially identified within a relatively short incubation time. It was the co-hydrolysis of caseins and some major MFGM proteins as anchors that destroyed the stability of MFGM. Furthermore, studies on the effect of trilayer membrane structure remaining at the interface on the hydrolysis rate of major MFGM proteins by plasmin revealed that ADPH and BTN were very sensitive to plasmin action, while PAS 7 was very resistant to plasmin action. Overall, membrane structure reduced the susceptibility of some major MFGM proteins to plasmin and provided protective effects. Therefore, this study provided important insights into the hydrolysis behavior of interfacial proteins in whole UI-UHT milk induced by plasmin.

Alginate oligosaccharide-mediated butyrate-HIF-1α axis improves skin aging in mice.

The "gut-skin" axis has been proved and is considered as a novel therapy for the prevention of skin aging. The antioxidant efficacy of oligomannonic acid (MAOS) make it an intriguing target for use to improve skin aging. The present study further explored whereby MAOS-mediated gut-skin axis balance prevented skin aging in mice. The data indicated the skin aging phenotypes, oxidative stress, skin mitochondrial dysfunction, and intestinal dysbiosis (especially the butyrate and HIF-1α levels decreased) in aging mice. Similarly, fecal microbiota transplantation (FMT) from aging mice rebuild the aging-like phenotypes. Further, we demonstrated MAOS-mediated colonic butyrate-HIF-1α axis homeostasis promoted the entry of butyrate into the skin, upregulated mitophagy level and ultimately improving skin aging via HDAC3/PHD/HIF-1α/mitophagy loop in skin of mice. Overall, our study offered a better insights of the effectiveness of alginate oligosaccharides (AOS), promised to become a personalized targeted therapeutic agents, on gut-skin axis disorder inducing skin aging.

Single-site iron-anchored amyloid hydrogels as catalytic platforms for alcohol detoxification.

Constructing effective antidotes to reduce global health impacts induced by alcohol prevalence is a challenging topic. Despite the positive effects observed with intravenous applications of natural enzyme complexes, their insufficient activities and complicated usage often result in the accumulation of toxic acetaldehyde, which raises important clinical concerns, highlighting the pressing need for stable oral strategies. Here we present an effective solution for alcohol detoxification by employing a biomimetic-nanozyme amyloid hydrogel as an orally administered catalytic platform. We exploit amyloid fibrils derived from ß-lactoglobulin, a readily accessible milk protein that is rich in coordinable nitrogen atoms, as a nanocarrier to stabilize atomically dispersed iron (ferrous-dominated). By emulating the coordination structure of the horseradish peroxidase enzyme, the single-site iron nanozyme demonstrates the capability to selectively catalyse alcohol oxidation into acetic acid, as opposed to the more toxic acetaldehyde. Administering the gelatinous nanozyme to mice suffering from alcohol intoxication significantly reduced their blood-alcohol levels (decreased by 55.8% 300 min post-alcohol intake) without causing additional acetaldehyde build-up. Our hydrogel further demonstrates a protective effect on the liver, while simultaneously mitigating intestinal damage and dysbiosis associated with chronic alcohol consumption, introducing a promising strategy in effective alcohol detoxification.

Improvement in the Sustained-Release Performance of Electrospun Zein Nanofibers via Crosslinking Using Glutaraldehyde Vapors.

Volatile active ingredients in biopolymer nanofibers are prone to burst and uncontrolled release. In this study, we used electrospinning and crosslinking to design a new sustained-release active packaging containing zein and eugenol (EU). Vapor-phase glutaraldehyde (GTA) was used as the crosslinker. Characterization of the crosslinked zein nanofibers was conducted via scanning electron microscopy (SEM), mechanical properties, water resistance, and Fourier transform infrared (FT-IR) spectroscopy. It was observed that crosslinked zein nanofibers did not lose their fiber shape, but the diameter of the fibers increased. By increasing the crosslink time, the mechanical properties and water resistance of the crosslinked zein nanofibers were greatly improved. The FT-IR results demonstrated the formation of chemical bonds between free amino groups in zein molecules and aldehyde groups in GTA molecules. EU was added to the zein nanofibers, and the corresponding release behavior in PBS was investigated using the dialysis membrane method. With an increase in crosslink time, the release rate of EU from crosslinked zein nanofibers decreased. This study demonstrates the potential of crosslinking by GTA vapors on the controlled release of the zein encapsulation structure containing EU. Such sustainable-release nanofibers have promising potential for the design of fortified foods or as active and smart food packaging.

Samarium-Oxo/Hydroxy Cluster: A Solar Photocatalyst for Chemoselective Aerobic Oxidation of Thiols for Disulfide Synthesis.

Oxidation contributes as a secondary driver of the prevailing carbon emission in the chemical industries. To address this issue, photocatalytic aerobic oxidation has emerged as a promising alternative. However, the challenge of achieving satisfactory chemoselectivity and effective use of solar light has hindered progress in this area. In this context, the present study introduces a novel homogeneous photocatalyst, [Sm6O(OH)8(H2O)24]I8(H2O)8 cluster (Sm-OC), via a unique auxiliary ligand-free oxidative hydrolysis. Using Sm-OC as catalyst, a solar photocatalyzed aerobic oxidation of thiols has been developed for the synthesis of valuable disulfides. Remarkably, this catalyst manifested a significant turnover number ≥2000 under tested conditions. Sm-OC-catalyzed aerobic oxidation showcased remarkable chemoselectivity. In thiol oxidations, despite the vulnerability of disulfides toward overoxidation, overoxidized byproducts or oxidation of nontarget functional groups was not detected across all 28 tested substrates. This investigation presents the first application of a lanthanide-oxo/hydroxy cluster in photocatalysis.

Faecalibacterium prausnitzii Supplementation Prevents Intestinal Barrier Injury and Gut Microflora Dysbiosis Induced by Sleep Deprivation.

Sleep deprivation (SD) leads to impaired intestinal barrier function and intestinal flora disorder, especially a reduction in the abundance of the next generation of probiotic Faecalibacterium prausnitzii (F. prausnitzii). However, it remains largely unclear whether F. prausnitzii can ameliorate SD-induced intestinal barrier damage. A 72 h SD mouse model was used in this research, with or without the addition of F. prausnitzii. The findings indicated that pre-colonization with F. prausnitzii could protect against tissue damage from SD, enhance goblet cell count and MUC2 levels in the colon, boost tight-junction protein expression, decrease macrophage infiltration, suppress pro-inflammatory cytokine expression, and reduce apoptosis. We found that the presence of F. prausnitzii helped to balance the gut microbiota in SD mice by reducing harmful bacteria like Klebsiella and Staphylococcus, while increasing beneficial bacteria such as Akkermansia. Ion chromatography analysis revealed that F. prausnitzii pretreatment increased the fecal butyrate level in SD mice. Overall, these results suggested that incorporating F. prausnitzii could help reduce gut damage caused by SD, potentially by enhancing the intestinal barrier and balancing gut microflora. This provides a foundation for utilizing probiotics to protect against intestinal illnesses.

Age Gelation in Direct Steam Infusion Ultra-High-Temperature Milk: Different Heat Treatments Produce Different Gels.

To investigate the gelation process of direct ultra-high-temperature (UHT) milk, a pilot-scale steam infusion heat treatment was used to process milk samples over a wide temperature of 142-157 °C for 0.116-6 s, followed by storage at 4 °C, 25 °C, and 37 °C. The results of the physicochemical properties of milk showed that the particle sizes and plasmin activities of all milk samples increased during storage at 25 °C, but age gelation only occurred in three treated samples, 147 °C/6 s, 142 °C/6 s, and 142 °C/3 s, which all had lower plasmin activities. Furthermore, the properties of formed gels were further compared and analyzed by the measures of structure and intermolecular interaction. The results showed that the gel formed in the 147 °C/6 s-treated milk with a higher C* value had a denser network structure and higher gel strength, while the 142 °C/6 s-treated milk had the highest porosity. Furthermore, disulfide bonds were the largest contributor to the gel structure, and there were significant differences in disulfide bonds, hydrophobic interaction forces, hydrogen bonds, and electrostatic force among the gels. Our results showed that the occurrence of gel was not related to the thermal load, and the different direct UHT treatments produced different age gels in the milk.

Age-Dependent Inflammatory Microenvironment Mediates Alveolar Regeneration.

Lung aging triggers the onset of various chronic lung diseases, with alveolar repair being a key focus for alleviating pulmonary conditions. The regeneration of epithelial structures, particularly the differentiation from type II alveolar epithelial (AT2) cells to type I alveolar epithelial (AT1) cells, serves as a prominent indicator of alveolar repair. Nonetheless, the precise role of aging in impeding alveolar regeneration and its underlying mechanism remain to be fully elucidated. Our study employed histological methods to examine lung aging effects on structural integrity and pathology. Lung aging led to alveolar collapse, disrupted epithelial structures, and inflammation. Additionally, a relative quantification analysis revealed age-related decline in AT1 and AT2 cells, along with reduced proliferation and differentiation capacities of AT2 cells. To elucidate the mechanisms underlying AT2 cell functional decline, we employed transcriptomic techniques and revealed a correlation between inflammatory factors and genes regulating proliferation and differentiation. Furthermore, a D-galactose-induced senescence model in A549 cells corroborated our omics experiments and confirmed inflammation-induced cell cycle arrest and a >30% reduction in proliferation/differentiation. Physiological aging-induced chronic inflammation impairs AT2 cell functions, hindering tissue repair and promoting lung disease progression. This study offers novel insights into chronic inflammation's impact on stem cell-mediated alveolar regeneration.

Solobacterium moorei promotes the progression of adenomatous polyps by causing inflammation and disrupting the intestinal barrier.

BACKGROUND: Adenomatous polyps (APs) with inflammation are risk factors for colorectal cancer. However, the role of inflammation-related gut microbiota in promoting the progression of APs is unknown. METHODS: Sequencing of the 16S rRNA gene was conducted to identify characteristic bacteria in AP tissues and normal mucosa. Then, the roles of inflammation-related bacteria were clarified by Spearman correlation analysis. Furthermore, colorectal HT-29 cells, normal colon NCM460 cells, and azoxymethane-treated mice were used to investigate the effects of the characteristic bacteria on progression of APs. RESULTS: The expression levels of inflammation-related markers (diamine oxidase, D-lactate, C-reactive protein, tumor necrosis factor-α, interleukin-6 and interleukin-1ß) were increased, whereas the expression levels of anti-inflammatory factors (interleukin-4 and interleukin-10) were significantly decreased in AP patients as compared to healthy controls. Solobacterium moorei (S. moorei) was enriched in AP tissues and fecal samples, and significantly positively correlated with serum inflammation-related markers. In vitro, S. moorei preferentially attached to HT-29 cells and stimulated cell proliferation and production of pro-inflammatory factors. In vivo, the incidence of intestinal dysplasia was significantly increased in the S. moorei group. Gavage of mice with S. moorei upregulated production of pro-inflammatory factors, suppressed proliferation of CD4+ and CD8+cells, and disrupted the integrity of the intestinal barrier, thereby accelerating progression of APs. CONCLUSIONS: S. moorei accelerated the progression of AP in mice via activation of the NF-κB signaling pathway, chronic low-grade inflammation, and intestinal barrier disruption. Targeted reduction of S. moorei presents a potential strategy to prevent the progression of APs.

Decoding Molecular Mechanism Underlying Human Olfactory Receptor OR8D1 Activation by Sotolone Enantiomers.

Sotolone, a chiral compound, plays an important role in the food industry. Herein, (R)-/(S)-sotolone were separated to determine their odor characteristics and thresholds in air (R-form: smoky, burned, herb, and green aroma, 0.0514 µg/m3; S-form: sweet, milk, acid, and nutty aroma, 0.0048 µg/m3). OR8D1 responses to (R)-/(S)-sotolone were detected in a HEK293 cell-based luminescence assay. (S)-Sotolone was a more potent agonist than (R)-sotolone (EC50 values of 84.98 ± 1.05 and 167.20 ± 0.25 µmol/L, respectively). Molecular dynamics simulations and molecular mechanics Poisson-Boltzmann surface area analyses confirmed that the combination of (S)-sotolone and OR8D1 was more stable than that of (R)-sotolone. Odorant docking, multiple sequence alignments, site-directed mutagenesis, and functional studies with recombinant odorant receptors (ORs) in a cell-based luminescence assay identified 11 amino-acid residues that influence the enantioselectivity of OR8D1 toward sotolone significantly and that N2065.46 was indispensable to the activation of OR8D1 by (S)-sotolone.

Preparation of pH-responsive chitosan microspheres containing aminopeptidase and their application in accelerating cheese ripening.

Microencapsulated enzymes have been found to effectively accelerate cheese ripening. However, microencapsulated enzyme release is difficult to control, often resulting in enzyme release during cheese processing and causing texture and flavor defects. This study aims to address this issue by developing aminopeptidase-loaded pH-responsive chitosan microspheres (A-CM) for precise enzyme release during cheese ripening. An aminopeptidase with an isoelectric point (pH 5.4) close to the pH value of cheese ripening was loaded on chitosan microspheres through electrostatic interaction. Turbidity titration measurements revealed that pH 6.5 was optimal for binding aminopeptidase and microspheres, affording the highest loading efficiency of 58.16%. Various characterization techniques, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy confirmed the successful loading of aminopeptidase molecules on the chitosan microspheres. In vitro release experiments conducted during simulated cheese production demonstrated that aminopeptidase release from A-CM was pH responsive. The microspheres retained the enzyme during the coagulation and cheddaring processes (pH 5.5-6.5) and only released it after entering the cheese-ripening stage (pH 5.0-5.5). By loading aminopeptidase on chitosan microspheres, the loss rate of the enzyme in cheese whey was reduced by approximately 79%. Furthermore, compared with cheese without aminopeptidase and cheese with aminopeptidase added directly, the cheeses made with A-CM exhibited the highest proteolysis level and received superior sensory ratings for taste and smell. The content of key aroma substances, such as 2/3-methylbutanal and ethyl butyrate, in cheese with A-CM was more than 15 times higher than the others. This study provides an approach for accelerating cheese ripening through the use of microencapsulated enzymes.

Dynamic Transformation of Nano-MoS2 in a Soil-Plant System Empowers Its Multifunctionality on Soybean Growth.

Molybdenum disulfide (nano-MoS2) nanomaterials have shown great potential for biomedical and catalytic applications due to their unique enzyme-mimicking properties. However, their potential agricultural applications have been largely unexplored. A key factor prior to the application of nano-MoS2 in agriculture is understanding its behavior in a complex soil-plant system, particularly in terms of its transformation. Here, we investigate the distribution and transformation of two types of nano-MoS2 (MoS2 nanoparticles and MoS2 nanosheets) in a soil-soybean system through a combination of synchrotron radiation-based X-ray absorption near-edge spectroscopy (XANES) and single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS). We found that MoS2 nanoparticles (NPs) transform dynamically in soil and plant tissues, releasing molybdenum (Mo) and sulfur (S) that can be incorporated gradually into the key enzymes involved in nitrogen metabolism and the antioxidant system, while the rest remain intact and act as nanozymes. Notably, there is 247.9 mg/kg of organic Mo in the nodule, while there is only 49.9 mg/kg of MoS2 NPs. This study demonstrates that it is the transformation that leads to the multifunctionality of MoS2, which can improve the biological nitrogen fixation (BNF) and growth. Therefore, MoS2 NPs enable a 30% increase in yield compared to the traditional molybdenum fertilizer (Na2MoO4). Excessive transformation of MoS2 nanosheets (NS) leads to the overaccumulation of Mo and sulfate in the plant, which damages the nodule function and yield. The study highlights the importance of understanding the transformation of nanomaterials for agricultural applications in future studies.

Efficacy of Bifidobacterium animalis subsp. lactis BL-99 in the treatment of functional dyspepsia: a randomized placebo-controlled clinical trial.

Current treatment for functional dyspepsia (FD) has limited and unsustainable efficacy. Probiotics have the sustainable potential to alleviate FD. This randomized controlled clinical trial (Chinese Clinical Trial Registry, ChiCTR2000041430) assigned 200 FD patients to receive placebo, positive-drug (rabeprazole), or Bifidobacterium animalis subsp. lactis BL-99 (BL-99; low, high doses) for 8-week. The primary outcome was the clinical response rate (CRR) of FD score after 8-week treatment. The secondary outcomes were CRR of FD score at other periods, and PDS, EPS, serum indicators, fecal microbiota and metabolites. The CRR in FD score for the BL-99_high group [45 (90.0%)] was significantly higher than that for placebo [29 (58.0%), p = 0.001], BL-99_low [37 (74.0%), p = 0.044] and positive_control [35 (70.0%), p = 0.017] groups after 8-week treatment. This effect was sustained until 2-week after treatment but disappeared 8-week after treatment. Further metagenomic and metabolomics revealed that BL-99 promoted the accumulation of SCFA-producing microbiota and the increase of SCFA levels in stool and serum, which may account for the increase of serum gastrin level. This study supports the potential use of BL-99 for the treatment of FD.

Up-regulation of sortase-dependent pili in Bifidobacterium longum BBMN68 in response to bile stress enhances its adhesion to HT-29 cells.

Adhesion to gastrointestinal tract is crucial for bifidobacteria to exert their probiotic effects. Our previous work found that bile salts significantly enhance the adhesion ability of Bifidobacterium longum BBMN68 to HT-29 cells. In this study, trypsin-shaving and LC-MS/MS-based surface proteomics were employed to identify surface proteins involved in bile stress response. Among the 829 differentially expressed proteins, 56 up-regulated proteins with a fold change >1.5 were subjected to further analysis. Notably, the minor pilin subunit FimB was 4.98-fold up-regulated in response to bile stress. In silico analysis and RT-PCR confirmed that gene fimB, fimA and srtC were co-transcribed and contributed to the biosynthesis of sortase-dependent pili Pil1. Moreover, scanning electron microscopy and immunogold electron microscopy assays showed increased abundance and length of Pil1 on BBMN68 under bile stress. As the major pilin subunit FimA serves as adhesion component of Pil1, an inhibition assay using anti-FimA antibodies further confirmed the critical role of Pil1 in mediating the adhesion of BBMN68 to HT-29 cells under bile stress. Our findings suggest that the up-regulation of Pil1 in response to bile stress enhances the adhesion of BBMN68 to intestinal epithelial cells, highlighting a novel mechanism of gut persistence in B. longum strains.

The activator protein-1 complex governs a vascular degenerative transcriptional programme in smooth muscle cells to trigger aortic dissection and rupture.

BACKGROUND AND AIMS: Stanford type A aortic dissection (AD) is a degenerative aortic remodelling disease marked by an exceedingly high mortality without effective pharmacologic therapies. Smooth muscle cells (SMCs) lining tunica media adopt a range of states, and their transformation from contractile to synthetic phenotypes fundamentally triggers AD. However, the underlying pathomechanisms governing this population shift and subsequent AD, particularly at distinct disease temporal stages, remain elusive. METHODS: Ascending aortas from nine patients undergoing ascending aorta replacement and five individuals undergoing heart transplantation were subjected to single-cell RNA sequencing. The pathogenic targets governing the phenotypic switch of SMCs were identified by trajectory inference, functional scoring, single-cell regulatory network inference and clustering, regulon, and interactome analyses and confirmed using human ascending aortas, primary SMCs, and a ß-aminopropionitrile monofumarate-induced AD model. RESULTS: The transcriptional profiles of 93 397 cells revealed a dynamic temporal-specific phenotypic transition and marked elevation of the activator protein-1 (AP-1) complex, actively enabling synthetic SMC expansion. Mechanistically, tumour necrosis factor signalling enhanced AP-1 transcriptional activity by dampening mitochondrial oxidative phosphorylation (OXPHOS). Targeting this axis with the OXPHOS enhancer coenzyme Q10 or AP-1-specific inhibitor T-5224 impedes phenotypic transition and aortic degeneration while improving survival by 42.88% (58.3%-83.3% for coenzyme Q10 treatment), 150.15% (33.3%-83.3% for 2-week T-5224), and 175.38% (33.3%-91.7% for 3-week T-5224) in the ß-aminopropionitrile monofumarate-induced AD model. CONCLUSIONS: This cross-sectional compendium of cellular atlas of human ascending aortas during AD progression provides previously unappreciated insights into a transcriptional programme permitting aortic degeneration, highlighting a translational proof of concept for an anti-remodelling intervention as an attractive strategy to manage temporal-specific AD by modulating the tumour necrosis factor-OXPHOS-AP-1 axis.

Emulsion stability of hydroxybutyl chitosan as emulsifier at low pH: Effects of the degree of substitutions of hydroxybutyl groups.

Keeping the stability of emulsions at low pH is necessary for their successful applications in food and delivery systems. To achieve this goal, hydroxybutyl chitosan (HBC) with three degrees of substitution (DSs) was used as an emulsifier to investigate the effect of HBC structure on the emulsion stability. The DSs of HBC-5, HBC-10, and HBC-20 were 0.66, 1.51, and 2.19, respectively. The stability of oil-in-water emulsions against creaming/coalescence was positively correlated with the DS. As pH decreased to 2, HBC-20-stabilized emulsions were most stable without creaming or coalescence. After 30 days of storage, no changes in the droplet sizes of HBC-20-stabilized emulsions were observed, whereas the droplet sizes of HBC-5/10- stabilized emulsions significantly increased at low pH. The stability of HBC-20- stabilized emulsions at low pH was attributed to the higher surface activity and electrostatic repulsion. Our research revealed that the emulsion stability of HBC under low pH conditions can be controlled by the density of the hydroxybutyl groups in HBC. In vitro digestion further revealed the excellent stability of HBC-20-stabilized emulsions in simulated gastric fluid, which highlighted the enormous potential of HBC-20 to protect liposoluble drugs and nutrients from the extreme pH environment.

CO2 electrocatalytic reduction to ethylene and its application outlook in food science.

The efficient conversion of CO2 is considered to be an important step toward carbon emissions peak and carbon neutrality. Presently, great efforts have been devoted to the study of efficient nanocatalysts, electrolytic cell, and electrolytes to achieve high reactivity and selectivity in the electrochemical reduction of CO2 to mono- and multi-carbon (C2+) compounds. However, there are very few reviews focusing on highly reactive and selective ethylene production and application in the field of electrochemical carbon dioxide reduction reaction (CO2RR). Ethylene is a class of multi-carbon compounds that are widely applied in industrial, ecological, and agricultural fields. This review focuses especially on the convertibility of CO2 reduction to generate ethylene technology in practical applications and provides a detailed summary of the latest technologies for the efficient production of ethylene by CO2RR and suggests the potential application of CO2RR systems in food science to further expand the application market of CO2RR for ethylene production.

Characteristics and antioxidant activity of Maillard reaction products from ß-lactoglobulin and isomaltooligosaccharide.

Starch-derived isomaltooligosaccharide (IMO) is potentially used as prebiotics in infant formulas. Given that they are non-digestible carbohydrates rich in reducing substrates, it's crucial to understand if they can interact with ß-lactoglobulin (ß-LG) to produce Maillard reaction products (MRPs) and how these MRPs might influence the nutritional properties of ß-LG. In our investigation, we conjugated ß-LG with IMO to generate MRPs. Using a spectrophotometer, we identified the intermediates and assessed browning. We also evaluated changes in free amino groups and structural alterations. The antioxidative activity of the resulting compounds was assessed using DPPH and the ferric reducing/antioxidant power (FRAP) assay. Our data revealed increased visible absorption and fluorescence intensity, suggesting the formation of intermediate and browning products. The content of free amino groups diminished by 33%, supporting the conjugation of IMO with ß-LG. However, circular dichroism results indicated no significant alterations in the secondary structure of ß-LG. Notably, the ß-LG-IMO MRPs exhibited enhanced 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity and ferric reducing/antioxidant power (FRAP). The findings provide insights into the characteristics and antioxidant activities of the conjugates derived from IMO and dairy protein in infant formula.

Metagenome-wide analysis uncovers gut microbial signatures and implicates taxon-specific functions in end-stage renal disease.

BACKGROUND: The gut microbiota plays a crucial role in regulating host metabolism and producing uremic toxins in patients with end-stage renal disease (ESRD). Our objective is to advance toward a holistic understanding of the gut ecosystem and its functional capacity in such patients, which is still lacking. RESULTS: Herein, we explore the gut microbiome of 378 hemodialytic ESRD patients and 290 healthy volunteers from two independent cohorts via deep metagenomic sequencing and metagenome-assembled-genome-based characterization of their feces. Our findings reveal fundamental alterations in the ESRD microbiome, characterized by a panel of 348 differentially abundant species, including ESRD-elevated representatives of Blautia spp., Dorea spp., and Eggerthellaceae, and ESRD-depleted Prevotella and Roseburia species. Through functional annotation of the ESRD-associated species, we uncover various taxon-specific functions linked to the disease, such as antimicrobial resistance, aromatic compound degradation, and biosynthesis of small bioactive molecules. Additionally, we show that the gut microbial composition can be utilized to predict serum uremic toxin concentrations, and based on this, we identify the key toxin-contributing species. Furthermore, our investigation extended to 47 additional non-dialyzed chronic kidney disease (CKD) patients, revealing a significant correlation between the abundance of ESRD-associated microbial signatures and CKD progression. CONCLUSION: This study delineates the taxonomic and functional landscapes and biomarkers of the ESRD microbiome. Understanding the role of gut microbiota in ESRD could open new avenues for therapeutic interventions and personalized treatment approaches in patients with this condition.