內(nèi)容: Emerging evidence of the beneficial effects of defatted rice bran (DFRB) on gut health has advanced the development of fermented defatted rice bran as a potential functional food. However, less is known about its effects and underlying mechanisms on gut health. In this study, a mouse model together with fecal microbiota transplantation (FMT) was utilized to study the effects and mechanisms of fermented DFRB (FR) on gut barrier function. We found that FR improved the intestinal morphology, gut tight junction proteins, mucin, antimicrobial peptides, and interleukin 22 (IL-22) and promoted the gut Clostridium butyricum and butyrate. Notably, correlation analysis indicated gut C. butyricum and butyrate were two FR-induced effectors that improved gut health. FMT results suggested that C. butyricum, butyrate, and fecal microbiota from the FR group all reduced prolyl hydroxylase 2 (PHD2) expression by activating peroxisome proliferator-activated receptor gamma (PPARγ) in the mouse colon. This decrease in gut PHD2 subsequently upregulated the hypoxia-inducible factor-1 alpha (HIF-1α) expression, which in turn increased the expression of its targeted downstream tight junction proteins, mucin and antimicrobial peptides, and colonic IL-22 secretion. Overall, FR-derived C. butyricum and butyrate might improve gut barrier function through the HIF-1 signaling pathway, which provides a reference for the application of fermented DFRB as a potential functional food for improving of gut barrier function.

內(nèi)容: This study provides different opinion for exploring the mechanism of catechin (CAT) relieving nonalcoholic steatohepatitis (NASH), it is more innovative to explore from the perspective of intestinal microorganism. Through in vitro fermentation experiments, CAT could improve the abundance of Enterococcus, and Enterococcus faecalis (EF) accounts for the vast majority of Enterococcus in human gut. The experimental results in vivo showed that EF group and CAT + EF group could reduce the body weight, liver index and epididymal fat index of NASH mice, and improve the changes of serum and liver indexes. Hematoxylin-eosin staining observation showed that these two groups have greatly improved the fatty degeneration, balloon degeneration and necrotic focus caused by NASH. The alleviation of CAT + EF group was more obvious. Results of targeted metabonomics showed that CAT could promote EF to produce more methyl palmitate (C16:0), which plays a great role in relieving NASH. Our results indicated that EF could alleviate NASH and CAT + EF group had better alleviation may due to more production of methyl palmitate (C16:0) by EF. This study provides a new idea for CAT to alleviate NASH.

內(nèi)容: In this work, a novel electrochemical sensor based on covalent organic framework@carbon black@molecularly imprinted polydopamine (COF@CB@MPDA) was developed for selective recognition and determination of ciprofloxacin (CF). COF@CB@MPDA possessed good water dispersibility and was synthesized by the selfpolymerization of dopamine under alkaline conditions in the presence of the COF, CB and CF. The high surface area COF enhanced the adsorption of CF, whilst CB gave the composites high electrical conductivity to improve the sensitivity of the proposed COF@CB@MPDA/glassy carbon electrode (GCE) sensor. The specific recognition of CF by COF@CB@MPDA involved hydrogen bonding and van der Waals interactions. Under optimized conditions, the sensor showed a good linear relationship with CF concentration over the range of 5.0 × 10–7 and 1.0 × 10–4 mol/L, with a limit of detection (LOD) of 9.53 × 10–8 mol/L. Further, the developed sensor exhibited high selectivity, repeatability and stability for CF detection in milk and milk powders. The method used to fabricate the COF@CB@MPDA/GCE sensor could be easily adapted for the selective recognition and detection of other antibacterial agents and organic pollutants in the environment.

內(nèi)容: The valorization of vegetable by-products is a promising strategy to combat climate change and achieve global carbon neutrality goals. This study aimed to exploit the high-value utilization of garlic by-products and to investigate the antihypertensive effects and potential mechanisms of the resulting angiotensin I-converting enzyme (ACE) inhibitory peptides. After protein extraction, enzymatic hydrolysis, and activity-directed fractionation, a potent and highly stable ACE inhibitory peptide (IC50: 31.38 μmol/L) was obtained, which was identified as VWAS and acted as a competitive inhibitor. VWAS stably bound to key residues in the ACE active center mainly through hydrogen bonding interactions and effectively lowered blood pressure in spontaneously hypertensive rats via alleviating renal and cardiac injuries, improving endothelial dysfunction, and regulating the renal renin-angiotensin system, antioxidant system, and anti-inflammatory system. These findings suggested that garlic protein-derived peptide (VWAS) was a desirable candidate for antihypertensive functional foods and provided guidance for the high-value utilization of garlic by-products.

內(nèi)容: Bigeye tuna is a protein-rich fish that is susceptible to spoilage during cold storage, however, there is limited information on untargeted metabolomic profiling of bigeye tuna concerning spoilage-associated enzymes and metabolites. This study aimed to investigate how cold storage affects enzyme activities, nutrient composition, tissue microstructures and spoilage metabolites of bigeye tuna. The activities of cathepsins B, H, L increased, while Na+/K+-ATPase and Mg2+-ATPase decreased, α-glucosidase, lipase and lipoxygenase first increased and then decreased during cold storage, suggesting that proteins undergo degradation and ATP metabolism occurs at a faster rate during cold storage. Nutrient composition (moisture and lipid content), total amino acids decreased, suggesting that the nutritional value of bigeye tuna was reduced. Besides, a logistic regression equation has been established as a food analysis tool and assesses the dynamics and correlation of the enzyme of bigeye tuna during cold storage. Based on untargeted metabolomic profiling analysis, a total of 524 metabolites were identified in the bigeye tuna contained several spoilage metabolites involved in lipid metabolism (glycerophosphocholine and choline phosphate), amino acid metabolism (L-histidine, 5-deoxy-5′-(methylthio) adenosine, 5-methylthioadenosine), carbohydrate metabolism (D-gluconic acid, α-D-fructose 1, 6-bisphosphate, D-glyceraldehyde 3-phosphate). The results of tissue microstructures of tuna showed a looser network and visible deterioration of tissue fiber during cold storage. Therefore, metabolomic analysis and tissue microstructures provide insight into the spoilage mechanism investigations on bigeye tuna during cold storage.

內(nèi)容: The gut microbiota and it’s metabolism are vital targets of probiotics regulating high fat-diet (HFD) induced hyperlipidemia, which can relieve the pressure caused by the striking growth of sub-health people. Pediococcus pentosaceus PP04 (PP04) could colonize in intestine to regulate gut microbiota and it’s metabolites directly, the rebalanced intestinal flora mediated by PP04 could facilitate the secretion of short chain fatty acids to control body weight gain, PP04 intervention also changed bile acid (BA) profiles and enhanced the ileal concentrations of antagonists including tauro-α/β-muricholic acid sodium salt and ursodeoxycholic acid to inhibit intestinal farnesoid X receptor/fibroblast growth factor 15 (FXR/FGF15) signaling coupled with the activation of hepatic FXR/small heterodimer partners signaling, which accelerated the hepatic BA de novo synthesis and excretion with feces to eliminate HFD caused hyperlipemia effectively. This study provided important evidence regarding PP04 as dietary supplement to relieve hyperlipidemia by influencing BA enterohepatic circulation.

內(nèi)容: Aeromonas spp. are commonly found in spoilage of chilled meat. Aeromonas salmonicida NCM 29 and A. salmonicida NCM 57 have been discovered the spoilage heterogeneity in degrading myofibrillar protein. In this study, the two strains were tested to uncover the discrepancy of meat spoilage in collagen-rich chilled meat and extracted collagen. The results revealed that chicken claws, riched in collagen, inoculated with NCM 29 showed higher values of total viable counts (TVC), total volatile basic nitrogen (TVB-N), pH, adhered cells, trichloroacetic acid (TCA)-soluble peptides, and protease activity compared to those inoculated with NCM 57. Furthermore, NCM 29 generated higher quantity of volatile organic compounds related to meat spoilage. The collagenase ((hemagglutinin protease (Hap)) secreted by NCM 29 has been identified as the key factor responsible for the observed discrepancies in spoilage, which gradually degraded collagen into peptides and hydroxyproline. The capacity of Hap to degrade type I collagen in vitro indicated that it has apparent proteolytic activity, which could reduce the average particle size and alter secondary structure of collagen. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) further confirmed the degradation of the β-chain in collagen. These findings not only provide a theoretical basis for in-depth investigation of the meat spoilage mechanisms of Aeromonas spp., but also encourage us to take measures to avoid the spoilage of related bacteria such as Aeromonas spp. during the preservation process.

內(nèi)容: Chinese dwarf cherry (Cerasus humilis) is a fruit unique to China, which is considered to have osteoprotective effects. However, no systematic experimental characterization was available. In this study, the osteoprotective activity and mechanism of Chinese dwarf cherry polyphenol extract (OPE) was studied. In vitro, OPE stimulated the alkaline phosphatase activity in the early differentiation stage, increased the osteocalcin level in the middle differentiation stage, and induced the formation of more bonemineralized nodules in the late osteogenic stage. In vivo, OPE improved cancellous bone structure and maximum load of the femur in ovariectomized (OVX) rats. The balance between bone formation and resorption was regulated. Oxidative stress levels in the peripheral blood, liver and femur were reduced. OPE alleviated the disturbance in energy metabolism, muscle development, and muscle regulation-related signaling pathways caused by OVX and activated the calcium/adenosine monophosphate-activated protein kinase signaling pathway. Therefore, OPE is a potential dietary supplement for the prevention and treatment of osteoporosis.

內(nèi)容: The hurdle technology for food preservation effectively addresses the limitations of individual antimicrobial technologies by integrating their strengths. It can not only prolong the storage time of food but also maintains its high quality. In this study, three antimicrobial and bactericidal technologies, namely soluble gas stabilization (SGS), modified atmosphere packaging (MAP), and cold plasma (CP), were applied to chilled chicken breasts. The packaging, total viable count (TVC), and physicochemical properties of chilled chicken breasts after treatments and storage at 4 ℃ were monitored. The microbial diversity at the initial and end points of the storage time of each group was also analyzed. The results indicated that a 3?5 h SGS treatment can effectively increase the proportion of carbon dioxide in the MAP during the storage process of chilled chicken breasts, thereby alleviating the packaging collapse problem. Simultaneously, the effect of SGS, MAP, and CP combinational treatments significantly extended the storage time of chilled chicken breasts while maintaining the physicochemical qualities of samples. Compared to the control group, the TVC of chicken breast treated with SGS, MAP, and CP treatments decreased by 0.58 (lg(CFU/g)) at 0 day. The shelf life was extended by 5 days. After 8 days, the total volatile basic nitrogen (TVB-N) was 26.67 vs. 19.50 mg/100 g, thiobarbituric acid reactive substances (TBARS) was 0.99 vs. 0.72 mg MDA/kg, and TVC was 8.22 vs. 6.52 (lg(CFU/g)). High-throughput sequencing results showed that SGS and MAP treatments significantly reduce the proportion of Pseudomonas and Psychrobacter, which are sensitive to carbon dioxide, in the total bacterial genera. This study underscores the potential of integrating multiple antimicrobial technologies for effective food preservation.

內(nèi)容: Obesity has brought great challenges to global human health, and how to effectively prevent and control the occurrence and development of obesity has become an urgent problem. The role and mechanism of 4-[(α-Lrhamnosyloxy) benzyl] isothiocyanate (MITC), an active ingredient of Moringa oleifera Lam., in the regulation of lipid metabolism have not been comprehensively investigated. In the present study, we investigated the mechanism of MITC in inhibiting lipid accumulation in mice fed with a high-fat diet (HFD) in terms of both lipolysis and central appetite regulation mediated by the gut microbe-gut-brain axis. MITC enhanced the characteristic indices associated with HFD mice and also promoted adipocytolysis and brown fat thermogenesis. Moreover, MITC was observed to improve leptin resistance, modulate the composition of gut microbiota such as Ruminococcaceae, Parasutterella, and Acetatifactor, promote 5-hydroxytryptamine secretion, further enhance the secretion of glucagon-like peptide-1 (GLP-1) and peptide tyrosine-tyrosine (PYY) to activate peroxisome proliferator-activated receptor (PPAR) signaling in the hypothalamus, and modulate feeding behavior to inhibit lipid accumulation in HFD mice. These data suggest that MITC supplementation can help to alleviate obesity or obesity-related diseases.