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Abstract Ni–Fe‐based oxides are among the most promising catalysts developed to date for the bottleneck oxygen evolution reaction (OER) in water electrolysis. However, understanding and mastering the synergy of Ni and Fe remain challenging. Herein, we report that the synergy between Ni and Fe can be tailored by crystal dimensionality of Ni, Fe‐contained Ruddlesden–Popper (RP)‐type perovskites (La0.125Sr0.875)n+1(Ni0.25Fe0.75)nO3n+1 (n = 1, 2, 3), where the material with n = 3 shows the best OER performance in alkaline media. Soft X‐ray absorption spectroscopy spectra before and after OER reveal that the material with n = 3 shows enhanced Ni/Fe–O covalency to boost the electron transfer as compared to those with n = 1 and n = 2. Further experimental investigations demonstrate that the Fe ion is the active site and the Ni ion is the stable site in this system, where such unique synergy reaches the optimum at n = 3. Besides, as n increases, the proportion of unstable rock‐salt layers accordingly decreases and the leaching of ions (especially Sr2+) into the electrolyte is suppressed, which induces a decrease in the leaching of active Fe ions, ultimately leading to enhanced stability. This work provides a new avenue for rational catalyst design through the dimensional strategy.

Abstract Electrochemical carbon dioxide (CO2) reduction (ECR) is a promising technology to produce valuable fuels and feedstocks from CO2. Despite large efforts to develop ECR catalysts, the investigation of the catalytic performance and electrochemical behavior of complex metal oxides, especially perovskite oxides, is rarely reported. Here, the inorganic perovskite oxide Ag‐doped (La0.8Sr0.2)0.95Ag0.05MnO3–δ (LSA0.05M) is reported as an efficient electrocatalyst for ECR to CO for the first time, which exhibits a Faradaic efficiency (FE) of 84.3%, a remarkable mass activity of 75 A g−1 (normalized to the mass of Ag), and stability of 130 h at a moderate overpotential of 0.79 V. The LSA0.05M catalyst experiences structure reconstruction during ECR, creating the in operando‐formed interface between the perovskite and the evolved Ag phase. The evolved Ag is uniformly distributed with a small particle size on the perovskite surface. Theoretical calculations indicate the reconstruction of LSA0.05M during ECR and reveal that the perovskite–Ag interface provides adsorption sites for CO2 and accelerates the desorption of the *CO intermediate to enhance ECR. This study presents a novel high‐performance perovskite catalyst for ECR and may inspire the future design of electrocatalysts via the in operando formation of metal–metal oxide interfaces.

After undergoing 75% hot deformation and 40% cold deformation, a variant of TWIP (Twin Induced Plasticity) steel with a composition of Fe–22Mn−2.7Al−0.95C−0.75Si (wt.%) was subjected to annealing at various temperatures (850 °C, 650 °C, 550 °C) for 20min. The recovery annealed C550 sample exhibited a yield strength of 1289.20 MPa, a tensile strength of 1442.29 MPa and an elongation of 30.78%. Characterization and comparison of the samples were conducted using XRD, SEM, EBSD, TEM and uniaxial tensile tests. The yield strength of the sample was assessed through different strengthening mechanisms to analysis the exceptional properties of the recovery annealed sample. Experimental findings indicate that the high-density dislocation and the refinement of slip bands in the recovery annealed C550 samples contribute to their superior performance compared to the partially and fully recrystallized samples.

Fermented skim milk is an ideal food for consumers such as diabetic and obese patients, but its low-fat content affects its texture and viscosity. In this study, we developed an effective pretreatment method for fermented skim milk using low-frequency ultrasound (US), and investigated the molecular mechanism of the corresponding quality improvement. The skim milk samples were treated by optimal ultrasonication conditions (336 W power for 7 min at 3 °C), which improved the viscosity, water-holding capacity, sensory attributes, texture, and microstructure of fermented skim milk (P

Abstract In this study, the corrosion behavior of AlMn lightweight weathering steel (LWS) in the simulated marine atmosphere was investigated by means of the dry/wet corrosion cycle test. The results showed that Al was present as FeAl2O4 and enriched in the inner layer, which significantly optimizes the rust layer in terms of compactness, elemental distribution, phase constitution, and electrochemical properties. The Mn oxides promoted the formation of FeAl2O4 and enhanced the anti–rupture ability of the LWS’s rust layer.

Lactobacillus reuteri, which is present in fermented foods, can produce LPxTG motif proteins (LMPs) to help the strain resist gastrointestinal fluid environmental stress and enhance the adherence and colonizing properties. Intestinal nutrient small molecules can interact with LMPs and cooperate with Lactobacillus to exert probiotic effects in the host intestine. However, the mechanism of their correlation with gastrointestinal tolerance needs to be further studied. In this study, different kinds of nutritional food molecules, such as intestinal phenols, sugars, and acids, were screened and the interaction between the LPxTG proteins and small molecules was explored via the molecular docking approach. The docking results showed that phenols and oligosaccharides were more likely to bind to the LPxTG protein (B3XKV5), with the benzene ring, phenolic hydroxyl group, and glycosidic bond in the small molecule more easily binding to the active site of B3XKV5. Furthermore, the gastrointestinal tolerance was enhanced under the rutin, myricetin, quercetin phenols, and stachyose-treated L. reuteri strain groups, especially the phenol group, which revealed the relationship between the molecular interaction of the strain with the small molecules and strain tolerance mechanism. All the findings illustrated the gastrointestinal tolerance escape effect of the Lactobacillus strain under enriched intestinal nutrient small molecular conditions, and they also provide insight regarding the small molecules for the Lactobacillus strain under abnormal growth environments.

Abstract Recent studies have suggested that long-term application of anti-angiogenic drugs may impair oral mucosal wound healing. This study investigated the effect of sunitinib on oral mucosal healing impairment in mice and the therapeutic potential of Bifidobacterium breve (B. breve). A mouse hard palate mucosal defect model was used to investigate the influence of sunitinib and/or zoledronate on wound healing. The volume and density of the bone under the mucosal defect were assessed by micro-computed tomography (micro-CT). Inflammatory factors were detected by protein microarray analysis and enzyme-linked immunosorbent assay (ELISA). The senescence and biological functions were tested in oral mucosal stem cells (OMSCs) treated with sunitinib. Ligated loop experiments were used to investigate the effect of oral B. breve. Neutralizing antibody for interleukin-10 (IL-10) was used to prove the critical role of IL-10 in the pro-healing process derived from B. breve. Results showed that sunitinib caused oral mucosal wound healing impairment in mice. In vitro, sunitinib induced cellular senescence in OMSCs and affected biological functions such as proliferation, migration, and differentiation. Oral administration of B. breve reduced oral mucosal inflammation and promoted wound healing via intestinal dendritic cells (DCs)-derived IL-10. IL-10 reversed cellular senescence caused by sunitinib in OMSCs, and IL-10 neutralizing antibody blocked the ameliorative effect of B. breve on oral mucosal wound healing under sunitinib treatment conditions. In conclusion, sunitinib induces cellular senescence in OMSCs and causes oral mucosal wound healing impairment and oral administration of B. breve could improve wound healing impairment via intestinal DCs-derived IL-10.

Nitrite has the potential risk of hypoxic poisoning or cancer in pickled food. In our previous study, Limosilactobacillus fermentum (L. fermentum) RC4 is effective in nitrite degradation by producing nitrite reductase B (NirB). To investigate the detailed mechanism from the genome, response, and regulation of NirB, the whole-genome sequence of L. fermentum RC4 was analyzed, the L. fermentum-EGFP-nirB with enhanced green fluorescent protein (EGFP) labeled the nitrite reductase large subunit nirB, and the recombined L. fermentum-NirB with overexpression NirB strain was conducted. The key genes within the dominant metabolism pathways may be involved in stress tolerance to regulate the degrading process. The green fluorescence density of EGFP indicated that NirB activity has a threshold and peaked under 300 mg/L nitrite concentration. NirB overexpressed in L. fermentum RC4 boosted the enzyme activity by 39.6% and the degradation rate by 10.5%, when fermented in 300 mg/L for 40 h, compared to the control group. RNA-seq detected 248 differential genes mainly enriched in carbohydrate, amino acid, and energy metabolism. The ackA gene for pyruvate metabolism and the mtnN gene for cysteine metabolism were up-regulated. NirB regulates these genes to produce acid and improve stress resistance for L. fermentum RC4 to accelerate nitrite degradation.

Background: The increasing morbidity and mortality of cardiovascular disease have become a major factor in human death. Serum cholesterol is considered to be an important risk factor for inducing coronary heart disease, atherosclerosis and other cardiovascular diseases. To screen intestinal absorbable functional small peptides with cholesterol-lowering activity by enzymatic hydrolysis of whey protein and develop cholesterol-based functional food that may become a substitute for chemically synthesized drugs, providing new ideas for diseases caused by high cholesterol. Objective: This study aimed to evaluate the cholesterol-lowering activity of intestinal absorbable whey protein-derived peptides hydrolyzed by alkaline protease, trypsin and chymotrypsin, respectively. Method: The whey protein hydrolysates acquired by enzymatic hydrolysis under optimal conditions were purified by a hollow fiber ultrafiltration membrane with a molecular weight cutoff of 10 kDa. The fractions obtained by Sephadex G-10 gel filtration chromatography were transported through a Caco-2 cell monolayer. The transported peptides were detected in the basolateral aspect of Caco-2 cell monolayers using ultra- performance liquid chromatography-tandem mass spectrometry (UPLC-MS). Results: His-Thr-Ser-Gly-Tyr (HTSGY), Ala-Val-Phe-Lys (AVFK) and Ala-Leu-Pro-Met (ALPM) were unreported peptides with cholesterol-lowering activity. The cholesterol-lowering activities of the three peptides did not change significantly during simulated gastrointestinal digestion. Conclusion: This study not only provides theoretical support for the development of bioactive peptides that can be directly absorbed by the human body, but also provides new treatment ideas for hypercholesterolemia.

With the semi-finished and finished products of pickled and dried mustard in Ningbo as experimental materials, the dominant bacteria strains were isolated by ten-fold dilution method. The results showed that seven and three bacteria were obtained from the semi-finished and finished products, respectively, which were named as strain MGCB1~MGCB7 and strain MGC1~MGC3. The ten strains were identified by morphological observation, physiological and biochemical tests, and 16S rRNA sequence analysis. They were likely belong to Bacillus subtilis (MGCB1), Bacillus aerius (MGCB2), Bacillus altitudinis (MGCB3), Bacillus pumilus (MGCB4), Staphylococcus succinus (MGCB5), Staphylococcus succinus (MGCB6) and Bacillus amyloliquefaciens (MGCB7), Bacillus sp. (MGC1), Virgibacillus halodenitrificans (MGC2), and Cytobacillus gottheilii (MGC3), respectively. The protease activities of MGCB1 and MGCB7 were 16.39±0.79 and 13.45±0.46 U/mL, and the cellulase activities of MGCB1 and MGCB7 were 3.27±0.13 and 1.60±0.02 U/mL, respectively, after cultured at 37 ℃ for 96 h. These findings provide a useful reference for developing appropriate starter cultures to improve the quality of traditional pickled and dried mustard.

Casein was hydrolyzed by neutral protease, alkaline protease and trypsin to determine the best protease for preparation of cholesterol-lowering peptide. The effects of hydrolysis pH value, hydrolysis temperature, enzyme to substrate ratio, substrate concentration and hydrolysis time on casein hydrolysis degree and cholesterol micelle solubility inhibition rate were investigated by single factor and response surface experiments, and the optimal hydrolysis conditions were determined. Then the separation process of cholesterol-lowering peptide was determined by ultrafiltration and gel filtration chromatography. The results showed that the optimal enzyme was neutral protease, and the optimal hydrolysis conditions were as follows: Reaction temperature 51.3 ℃, enzyme to substrate concentration ratio 6.47%, pH6.34, substrate concentration 5 g/100 mL, reaction time 3.5 h , and cholesterol inhibition rate 58.25%±0.59%; The separation conditions of casein cholesterol-lowering peptide by Sephadex G-10 were as follows: Loading concentration 80 mg/mL, loading volume 2.5 mL, elution rate 3.5 mL/min; The inhibition rates of cholesterol solubility of peak 1 and peak 2 samples were 24.2%±0.24% and 4.3%±0.16% at 100 µg/mL after ultrafiltration and chromatography.

ABSTRACT: The by-products of milk fermentation by lactic acid bacteria provide potential health benefits to the balance of host intestinal microflora. In this study, the anti-inflammatory properties of fatty acids from monoculture-strain (Lactiplantibacillus plantarum A3) and multiple-strain (Streptococcus thermophilus, Lactobacillus bulgaricus, and L. plantarum A3 1:1:2) fermented milk were evaluated in a mouse model of dextran sulfate sodium-induced colitis, and the gut microbiota regulation properties of the fatty acids were also investigated. Results showed that fatty acids can attenuate the inflammatory response by inhibiting the expression of inflammatory factors IL-6 and tumor necrosis factor-α, and blocking the phosphorylation of the JNK in MAPK signal pathway. In addition, the relative abundance of the taxa Akkermansia and Lactobacillus were both enriched after the fatty acid intervention. This finding suggests that fatty acids from the milk fermentation with mixed lactic acid bacteria starters can reduce the severity of dextran sulfate sodium-induced colitis and enhance the abundance of the probiotics in the mice intestinal tract.

In order to improve the stability and water solubility of astaxanthin, the snailase was used for the wall-breaking extraction of astaxanthin from Haematococcus pluvialis, and gum arabic and whey protein powder (rich in milk fat globule membrane) were used as wall materials to prepare astaxanthin nanoparticles using a complex coacervation method, in addition, the stability of the nanoparticles was investigated. The results showed that the optimum conditions for the preparation of astaxanthin nanoparticles were pH4.0, protein/gum arabic mass ratio of 2:1 and astaxanthin concentration of 60 μmol/L. The encapsulation rate of astaxanthin under these conditions was 92.93%±0.19%. The average particle size was 265.71±0.55 nm and the Zeta potential was −13.44±0.14 mV. The nanoparticles showed good storage stability with only 6.1% increased in size, 90.78%±0.25% retention of astaxanthin and 79.31%±0.18% clearance of DPPH after 15 d storage at 4 ℃. This study would improve the stability and water solubility of astaxanthin and provide technical support for the efficient utilization of astaxanthin.

Abstract Purpose Uridine diphosphate glucose pyrophosphorylase (UGPase) plays an important role in glucose metabolism, catalyzing the reversible formation and decomposition of UDP-glucose (UDPG). In previous work, we found that UGPase is a key enzyme in lyophilization response for Lactobacillus acidophilus (L. acidophilus). However, its function and regulatory mechanism in the freeze-drying stress response are unknown. Herein, the effect of UGPase on freeze-drying survival rate of Staphylococcus carnosus (S. carnosus) was studied. Methods In this work, the genes LBA1719 encoding UGPase of L. acidophilus ATCC4356 were inserted into plasmid pMG-36e to construct the recombinant plasmid pMG-LBA1719 and then overexpressed in S. carnosus; the control group was S. carnosus transformed by pMG-36e. The lyophilization-survival rate of overexpressed S. carnosus was determined, and the differentially expressed genes (DEGs) were analyzed by transcriptome to disclose the mechanism of LBA1719 in regulating the lyophilization-survival rate. Results Compared with the control group, the UGPase activities of the overexpressed S. carnosus increased by 35.49%, while the lyophilization-survival rates decreased by 11.17% (p < 0.05). Overexpression of LBA1719 decreased the expression of genes gapA, gapB, and pgiA in carbohydrate metabolism and dapA, dapB, and dapE in amino acid metabolism, significantly changing the physiological characteristics of S. carnosus and decreasing its lyophilization-survival rate. Conclusion In summary, overexpression of UGPase accelerated the growth rate of S. carnosus and reduced its lyophilization-survival rates. GapA, gapB, pgiA, dapA, dapB, and dapE are vital to lyophilization protection in lactic acid bacteria (LAB). These findings provide new theoretical basis for analyzing the regulatory and molecular mechanisms of lyophilization resistance in LABs.

A potentially novel probiotic strain, YY-112, was previously isolated and identified as Lactiplantibacillus pentosus using 16S rDNA sequencing. The whole genome analysis showed that strain YY-112 has the potential to metabolize carbohydrates in the gastrointestinal environment and to regulate immunity. Further, comparative genomics analysis revealed that strain YY-112 was Lactiplantibacillus plantarum (L. plantarum) with more unique genes. The results of in vivo tests showed that L. plantarum YY-112 had no adverse effects and restored the damaged spleen and intestinal barrier of immunocompromised mice. L. plantarum YY-112 recovered the normal levels of lymphocytes, serum cytokines (Interferon-γ, tumor necrosis factor α, and interleukin-6), immunoglobulins (Ig) (IgA, IgM, and IgG) and lipids (albumin, cholesterol, triglyceride). Additionally, L. plantarum YY-112 might indirectly enhance the immune system by improving the intestinal microbiota structure. These results supported the potential of L. plantarum YY-112 as a probiotic to regulate the immune system of hosts.

In order to develop and utilize the milk polar lipids, the chloroform-methanol extraction method was used to extract the polar lipids from buttermilk. The phosphorus content as an index, the condition of chloroform-methanol volume ratio, liquid-to-methanol ratio, extraction temperature and time were optimized by single-factor experiment and the analysis of response surface methodology determined the optimum extraction conditions. The obtained samples were analyzed and identified by thin-layer chromatography(TLC). The results indicated that the optimal extraction conditions for polar lipids were: Chloroform-methanol volume ratio 2:1(v/v, %), 1:4(v/v, %) for the ratio of material to liquid, 20 ℃ for extraction temperature, and 10 min for extraction time. The phospholipid contents in the sample under this extracted condition was (1.647±0.010) mg/g, and there were polar lipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin. This process aims to provide a research basis for the extraction and development of milk polar lipids.

Abstract Background Cancer stem cells (CSCs) drive tumor initiation and progression and participate in tumor chemoresistance. We recently discovered that oral squamous cell carcinoma (OSCC) cells that highly express CD10 (CD10H cells) present cancer stem cells (CSC)-associated characteristics, which, in turn, affect the tumor growth, epithelial-mesenchymal transition (EMT), and resistance to cisplatin. In this study, we further investigated this mechanism in vitro and in vivo. We hypothesized that IL8 might regulate migration, invasion, and cisplatin resistance of CD10-positive oral cancer cells through the ERK pathway. Methods CD10 MicroBead Kit was used to select HN6 cells with high and low expression of CD10. The target protein IL8 was screened via protein chip assay. Lentiviral transduction and specific inhibitor were applied to investigate the signaling pathway. Real-time PCR, Western blot, and immunohistochemistry were used to analyze the mRNA and protein expression; transwell assay, spheroid formation assay, and cell viability assay were used to study the cell biological behavior in vitro; xenograft animal model was used to evaluate the tumor formation rate in vivo. Results Overexpression of CD10 promoted CSC-related genes expression and enhanced migration, invasion, spheroid formation, and chemoresistance in HN6 cells. Moreover, the overexpression of IL8 was detected in OSCC tumor tissue and cell lines (HN6 and CAL27) overexpressing CD10. IL8 secreted by CD10H HN6 promoted migration and invasion and restored tumor chemosensitivity via the p-ERK signaling pathway, while the inhibition of IL8 increased the chemosensitivity to cisplatin. Conclusions IL8 secretion by CD10 positive cells promotes migration, invasion, and cisplatin resistance of OSCC via the p-ERK signaling pathway.

Galactosyltransferase (GalT) is an important enzyme in synthesizing exopolysaccharide (EPS), the major polymer of biofilms protecting cells from severe conditions. However, the contribution to, and regulatory mechanism of GalT, in stressor resistance are still unclear. Herein, we successfully overexpressed GalT in Lactobacillus acidophilus NCFM by genetic engineering. The GalT activity and freeze-drying survival rate of the recombinant strain were significantly enhanced. The EPS yield also increased by 17.8%, indicating a positive relationship between freeze-drying resistance and EPS. RNA-Seq revealed that GalT could regulate the flux of the membrane transport system, pivotal sugar-related metabolic pathways, and promote quorum sensing to facilitate EPS biosynthesis, which enhanced freeze-drying resistance. The findings concretely prove that the mechanism of GalT regulating EPS biosynthesis plays an important role in protecting lactic acid bacteria from freeze-drying stress.

Nitrite is a common color and flavor enhancer in fermented meat products, but its secondary amines may transfer to the carcinogen N-nitrosamines. This review focuses on the sources, degradation, limitations, and alteration techniques of nitrite. The transition among NO3− and NO2−, NH4+, and N2 constitutes the balance of nitrogen. Exogenous addition is the most common source of nitrite in fermented meat products, but it can also be produced by contamination and endogenous microbial synthesis. While nitrite is degraded by acids, enzymes, and other metabolites produced by lactic acid bacteria (LAB), four nitrite reductase enzymes play a leading role. At a deeper level, nitrite metabolism is primarily regulated by the genes found in these bacteria. By incorporating antioxidants, chromogenic agents, bacteriostats, LAB, or non-thermal plasma sterilization, the amount of nitrite supplied can be decreased, or even eliminated. Finally, the aim of producing low-nitrite fermented meat products is expected to be achieved.

Abstract Background Brain death (BD) has been suggested to induce coronary endothelial dysfunction. Ischemia/reperfusion (IR) injury during heart transplantation may lead to further damage of the endothelium. Previous studies have shown protective effects of conditioned medium (CM) from bone marrow-derived mesenchymal stem cells (MSCs) against IR injury. We hypothesized that physiological saline-supplemented CM protects BD rats’ vascular grafts from IR injury. Methods The CM from rat MSCs, used for conservation purposes, indicates the presence of 23 factors involved in apoptosis, inflammation, and oxidative stress. BD was induced by an intracranial-balloon. Controls were subjected to a sham operation. After 5.5 h, arterial pressures were measured in vivo. Aortic rings from BD rats were harvested and immediately mounted in organ bath chambers (BD group, n = 7) or preserved for 24 h in 4 °C saline-supplemented either with a vehicle (BD-IR group, n = 8) or CM (BD-IR+CM group, n = 8), prior to mounting. Vascular function was measured in vitro. Furthermore, immunohistochemistry and quantitative real-time polymerase chain reaction (qRT-PCR) have been performed. Results BD in donors was associated with significantly impaired hemodynamic parameters and higher immunoreactivity of aortic myeloperoxidase (MPO), nitrotyrosine, caspase-3, caspase-8, caspase-9, and caspase-12 compared to sham-operated rats. In organ bath experiments, impaired endothelium-dependent vasorelaxation to acetylcholine in the BD-IR group compared to BD rats was significantly improved by CM (maximum relaxation to acetylcholine: BD 81 ± 2% vs. BD-IR 50 ± 3% vs. BD-IR + CM 72 ± 2%, p

ABSTRACT More and more people are aware of the importance of intestinal flora to human health, and people are interested in the regulation of intestinal flora and its interaction with the host. The survival status of the probiotics in the gastrointestinal environment and the microbial interactions between the lactic acid bacteria have also received considerable attention. In this study, the gastrointestinal environment tolerance, adhesion ability, and biofilm formation of the Lactobacillus strain in the coculture system were explored through the real-time fluorescence-based quantitative PCR, UPLC-MS/MS metabolic profiling analysis, and Live/Dead BacLight cell staining methods. The results showed that the coculture system could promote the release of signal molecules autoinducer-2 and effectively protect the viability of the Lactobacillus acidophilus in the gastrointestinal environment. Meanwhile, amino acid-derived characteristic metabolite l-alanine (1%) could effectively enhance the communication of the cells in the complex fermentation model, which led to an increase in the tolerance ability of the L. acidophilus by 28% in the gastrointestinal-like environment. IMPORTANCE It was deduced from the study that amino acid-derived metabolites play an important role in cell communication in the gastrointestinal tract (GIT) environment, thus enhancing the communication of Lactobacillus strains in the complex fermentation model. Meanwhile, the viability of Lactobacillus acidophilus can be increased in the coculture system during the gastrointestinal stress environment treated with the amino acid-derived quorum sensing (QS) molecule l-alanine. It will shed some light on the application of amino acid-derived QS molecules in the fermentation stater industry.

Superoxide dismutase (SOD) is an important antioxidant enzyme with different physiological functions, which can be used as a nutritional fortifier in food. Cereal-based fermented products are becoming popular worldwide. In this study, novel millet-based flavored yogurt enriched with SOD was developed. Lactiplantibacillus plantarum subsp. plantarum was screened, which manufactured SOD activity of 2476.21 ± 1.52 U g−1. The SOD content of millet yogurt was 19.827 ± 0.323 U mL−1, which was 63.01, 50.11, and 146.79% higher than that of Bright Dairy Yogurt 1911, Junlebao and Nanjing Weigang, respectively. Fifty-four volatile flavor substances and 22,571 non-volatile flavor substances were found in yogurt. Compared to traditional fermented yogurt, 37 non-volatile metabolites in yogurt with millet enzymatic fermentation broth were significantly upregulated, including 2-phenyl ethanol, hesperidin, N-acetylornithine and L-methionine, which were upregulated by 3169.6, 228.36, 271.22, and 55.67 times, respectively, thereby enriching the sensory and nutritional value of yogurt. Moreover, the manufacture of unpleasant volatile flavor substances was masked, making the product more compatible with consumers' tastes.

Microvascular dysfunction (MVD) in cardiac allografts is associated with an impaired endothelial function in the coronary microvasculature. Ischemia/reperfusion injury (IRI) deteriorates endothelial function. Hearts donated after circulatory death (DCD) are exposed to warm ischemia before initiating ex vivo blood perfusion (BP). The impact of cytokine adsorption during BP to prevent MVD in DCD hearts is unknown. In a porcine DCD model, we assessed the microvascular function of hearts after BP with (DCD-BPCytoS, n = 5) or without (DCD-BP, n = 5) cytokine adsorption (CytoSorb®). Microvascular autoregulation was assessed by increasing the coronary perfusion pressure, while myocardial microcirculation was measured by Laser-Doppler-Perfusion (LDP). We analyzed the immunoreactivity of arteriolar oxidative stress markers nitrotyrosine and 4-hydroxy-2-nonenal (HNE), endothelial injury indicating cell adhesion molecules CD54, CD106 and CD31, and eNOS. We profiled the concentration of 13 cytokines in the perfusate. The expression of 84 genes was determined and analyzed using machine learning and decision trees. Non-DCD hearts served as a control for the gene expression analysis. Compared to DCD-BP, relative LDP was improved in the DCD-BPCytoS group (1.51 ± 0.17 vs. 1.08 ± 0.17). Several pro- and anti-inflammatory cytokines were reduced in the DCD-BPCytoS group. The expression of eNOS significantly increased, and the expression of nitrotyrosine, HNE, CD54, CD106, and CD31, markers of endothelial injury, majorly decreased in the DCD-BPCytoS group. Three genes allowed exact differentiation between groups; regulation of HIF1A enabled differentiation between perfusion (DCD-BP, DCD-BPCytoS) and non-perfusion groups. CAV1 allowed differentiation between BP and BPCytoS. The use of a cytokine adsorption device during BP counteracts preload-dependent MVD and preserves the microvascular endothelium by preventing oxidative stress and IRI of coronary arterioles of DCD hearts.

The tumor microenvironment (TME) has a crucial role in tumor development, progression, and treatment response. Yet, the exact interaction between cancer biology and the TME is not fully understood. The following study analyzed the correlation between immune/stromal/estimate scores and survival prognosis in head and neck squamous cell carcinoma (HNSC) using a bioinformatic method. As a result, a predictive biomarker, UDP-glucose-specific G(i) protein-coupled P2Y receptor (P2RY14), was discovered. The potential role of P2RY14-driven signaling pathways in the immune-remodeling of TME was then investigated. Briefly, low immune scores were associated with unfavorable prognosis and clinical-stage, larger tumor size, and the down-regulation of P2RY14 in HNSC patients. In addition, the survival analysis showed that HNSC patients with high expression had longer survival than patients with low expression from both TCGA databases and our own patients. We further discovered that P2RY14 is involved in the immune activity in the TME of HNSC; a downregulation of P2RY14 resulted in being an indicator for the conversion of TME status (from immune-dominant to metabolic-dominant status). The intersection analysis of genes co-expressed with P2RY14 indicated that the T-cell receptor signaling pathway and PD-L1 expression and PD-1 checkpoint pathway were candidate signaling pathways driven by the P2RY14 gene in HNSC. Further investigation of immune-associated signaling pathways regulated by P2RY14 may help HNSC patients gain higher immunotherapy benefits.

Fluorescein isothiocyanate-labeled insulin (FITC-insulin) has been widely used for bioanalytical applications. Due to the high cost of commercial FITC-insulin and tedious labeling procedures described in the literature, there is still a need to develop a cost effective, reliable and quick labeling method for insulin. The purpose of the present work was to develop a quick and affordable method for FITC labeling of human insulin and to determine the effect of different conjugations of FITC to human insulin on its permeability through the MDCK cell monolayer. FITC labeling of insulin gives mono-, di- or tri-conjugates depending on the reaction time and the molar ratio of FITC:insulin. Mono-conjugate with unlabeled insulin, mixture of di- and tri-conjugate, and tri-conjugate with very little amount of di-conjugate were synthesized in less than 4 h. Degree of conjugation had an effect on the permeability of insulin through the MDCK cell monolayer. Mono-conjugate had higher permeability than the unlabeled insulin due to increase in partition coefficient. However, tri-conjugate showed lower permeability than the unlabeled insulin due to the increase in molecular weight. Keywords: Insulin, FITC labeling, Conjugates, MDCK cells, Mono-conjugate, Tri-conjugate

Probiotic candidate Lactobacillus reuteri DMSZ 8533 was screened out in vitro based on a relatively higher gastrointestinal tolerance and moderate adhesiveness. The organ index (spleen, thymus and liver), Interleukin-12 (IL-12), tumor necrosis factor-α (TNF-α), T-lymphocytes (CD3-, CD4- and CD-8 positive cells) and fecal microbiota composition were also investigated in BALB/c mice. Results showed a significant higher level of IL-12 at low-dose L. reuteri treated group in both females and males. The relative abundance of phylotypes in the phylum Bacteroidetes and Firmicutes exhibited a reserve shift between sexes after L. reuteri intervention. Meanwhile, the relative abundance of several taxa also differed markedly between sexes at low-dose group, together with microbiota diversity. Our finding demonstrates the importance of L. reuteri DMSZ 8533 as a potential probiotic strain with an immunomodulatory effect, which could also alter the microbiota composition depending on the sex of the host.

In spite of the high added value and tremendous output from duck processing industries, duck liver (DLv) is underutilized and a major factor is related to its prominent off-flavor perception which hampers the consumption and processing attributes. This work was designed to investigate the impact of low-frequency ultrasound (US) pretreatments on the headspace volatilome evolution of DLv and its isolated protein (DLvP) microstructure, aiming at exploring the potential of US technology to inhibit off-flavor perception and possible mechanisms behind. Results suggested that US pretreatment resulted in decreased lipid oxidation and off-flavor perception, simultaneously without significantly causing physicochemical influence including texture, pH and color. US induced obvious tertiary structural changes of DLvP, as revealed by the intrinsic fluorescence and surface hydrophobicity (H0), whereas the SH, S-S, secondary structure and molecular weight of DLvP remained unaffected, suggesting the presence of molten globule state (MG-state) under ultrasonic conditions. Besides, the headspace contents of flavor compounds, mainly aldehydes and alcohols, were significantly decreased whereas acids were increased. Multivariate analysis suggested an obvious US-induced effect on the volatilome evolution of DLv samples. Discriminant analysis recognized the aroma compounds including aldehydes and alkenals as the major contributors leading to the change of olfactory characteristics of DLv after ultrasonic treatment. Correlation analysis demonstrated the positive relationship between the volatile markers variation and the increased H0 values, a characteristic attribute of MG-state protein. The results obtained in this work suggested that US technology matched with suitable parameters could be a very promising approach to modulate the off-flavor perception of liver products by altering DLvP conformation.

Recent advances in immunotherapy, as a part of the multidisciplinary therapy, has gradually gained more attention. However, only a small proportion of patients who sensitive to the therapy could gain benefits. An increasing number of studies indicate that intestinal microbiota could enhance the efficiency of cancer immunotherapy. As one of the main probiotics, Bifidobacterium plays an important role in immune regulation, which has been proved by animal research and human clinical study. But the detailed mechanism was not clearly elucidated. Here we found oral administration of Bifidobacterium breve (B. breve) lw01 could significantly inhibit tumor growth and up-regulate tumor cell apoptosis, which relied on the recruitment of tumor-infiltrating lymphocytes and dendritic cells (DCs) in tumor microenvironment, but not Lactobacillus rhamnosus (L. rhamnosus) CGMCC 1.3724 or Escherichia coli (E. coli) MG1655. In the in situ ligated intestine loop model, B. breve’s stimulation triggered the upregulated expression of DC-related chemokine CCL20 and recruited more DCs in the intestinal villi. Further study revealed the enhancement of interleukin 12 (IL-12) secretion derived from DCs is essential to B. breve’s antitumor effect, which was counteracted by the treatment of neutralizing antibody for IL-12. Meanwhile, the modulation of intestinal microbiota caused by exogenous B. breve might enhance its antitumor effect. This study provides a simple and easy way to promote antitumor immunity via B. breve.

Objective: Refractory infection is an important factor affecting the progression of medication-related osteonecrosis of the jaw (MRONJ) from clinical stage I to stage II/III. The aim of this study was to explore the distribution of bacteria and their association with the inflammatory pathway of stage II/III MRONJ. Materials and Methods: Nine specimens of fresh inflammation tissue, located next to the necrotic bone or sequestrum, were collected from MRONJ patients. Nine specimens from normal oral mucosa were collected from healthy patients. The 16S rRNA gene sequencing method was used to determine the distribution characteristics of the bacterial colony. The protein microarray analysis was used to detect the expression of inflammatory cytokines. Results: The average relative abundance of Bacteroidetes, Spirochaetes, Synergistetes, and Tenericutes was higher, while Proteobacteria and Actinobacteria were lower in the MRONJ group. Most pro-inflammatory cytokines were up-regulated in the MRONJ group; yet, only IFNγ, TNFα, and IL8 showed statistical differences (P

Lactobacillus acidophilus NCFM is widely used in the fermentation industry; using it as a freeze-dried powder can greatly reduce the costs associated with packaging and transportation, and even prolong the storage period. Previously published research has reported that the expression of galU (EC: 2.7.7.9) is significantly increased as a result of freezing and drying. Herein, we aimed to explore how galU plays an important role in improving the resistance of Lactobacillus acidophilus NCFM to freeze-drying. For this study, galU was first knocked out and then re-expressed in L. acidophilus NCFM to functionally characterize its role in the pertinent metabolic pathways. The knockout strain ΔgalU showed lactose/galactose deficiency and displayed irregular cell morphology, shortened cell length, thin and rough capsules, and abnormal cell division, and the progeny could not be separated. In the re-expression strain pgalU, these inhibited pathways were restored; moreover, the pgalU cells showed a strengthened cell wall and capsule, which enhanced their resistance to adverse environments. The pgalU cells showed GalU activity that was 229% higher than that shown by the wild-type strain, and the freeze-drying survival rate was 84%, this being 4.7 times higher than that of the wild-type strain. To summarize, expression of the galU gene can significantly enhance gene expression in galactose metabolic pathway and make the strain form a stronger cell wall and cell capsule and enhance the resistance of the bacteria to an adverse external environment, to improve the freeze-drying survival rate of L. acidophilus NCFM.

This research sought to assess the anticancer effects of Lactobacillus acidophilus CICC 6074 and its underlying mechanism of action. L. acidophilus CICC 6074 inhibited HT-29 cell activity and induced its apoptosis in a dose- and time-dependent manner. HT-29 cells exposed to L. acidophilus CICC 6074 showed mitochondrial membrane potential (ΔΨm) loss, as well as Cyt c is released from the mitochondria into the cytoplasm, causing Bax, Caspase-9 and Caspase-3 to be up-regulated and Bcl-2 to be down-regulated. To further explore the mechanism by which L. acidophilus CICC 6074 achieves its anti-cancer effect, a HT-29 cell-induced colon cancer mouse model was used. Compared with a colon cancer model control group, the high-dose L. acidophilus CICC 6074 group showed obvious colon cancer cell apoptosis as measured by histological morphology, electron microscopy, and terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay. An in vivo study showed that L. acidophilus CICC 6074 induced colon cancer apoptosis by up-regulating Bax, down-regulating Bcl-2, releasing Cyt c from the mitochondria into the cytoplasm, and activating Caspase-3 and Caspase-9. These results demonstrate that L. acidophilus CICC 6074 exerts anticancer effects via the activation of mitochondrial pathways which then induce apoptosis. The research could provide new ideas and theoretical basis for development of probiotics functional food market.

Lactic acid bacteria (LAB) are demonstrably beneficial on the digestive and immune systems. S-layer protein (SlpA), as the outermost component of the cell wall, exerts an anti-inflammatory activity in lactobacilli, while the pro-inflammatory properties of SlpA in cross-talk with immune cells have rarely been investigated. Here, we showed that SlpA isolated from Lactobacillus acidophilus CICC 6074 exhibits more pronounced pro-inflammatory behavior through activating MAPK and NF-κB signaling, which was further corroborated by an increase in the NF-κB translocation from cytoplasm to the nucleus and DNA binding activity of NF-κB, triggered by SlpA treatment. Notably, a specific PKC inhibitor, chelerythrine, significantly blocked SlpA-elicited pro-inflammatory response, indicating that SlpA could act as stimulators of the innate immune system by triggering PKC to MAPK and NF-κB signaling pathway. This study provides important insights on the immunomodulatory properties of cell surface components in lactobacilli.

Neonatal necrotizing enterocolitis (NEC) is a serious inflammatory gastrointestinal disease in premature infants. Lactobacillus acidophilus is a probiotic, which exhibits many beneficial effects on the digestive and immune systems. In a rat model of NEC, administration of L. acidophilus CICC6074 reduced NEC symptoms, intestinal apoptosis and the levels of inflammatory cytokines TNF-α and IL-6. LiCl-treated L. acidophilus CICC6074 had less influence on the apoptosis index and TNF-α levels than untreated LA. In a TNF-α-infected Caco-2 cell model, purified L. acidophilus CICC6074 surface-layer protein (SLP) caused lower intestinal epithelial apoptosis, while decreasing IL-6 secretion in both the apical and basolateral compartments. SLP also reduced IL-6 and caspase-3 production in a lipopolysaccharide (LPS)-induced Caco-2 cell model. The results showed that L. acidophilus CICC6074 has the ability to reduce NEC symptoms. SLP of LA may play a role in reducing NEC symptoms by suppressing intestinal cell apoptosis and modulating intestinal immune function.