内容: As one of the adhesion-related surface factors on the cell wall of Lactobacillus strains, Leu-Pro-x-Thr-Gly (LPxTG) motif anchored proteins play a critical role in adhesion and molecular cross-talk with the host in the gastrointestinal tract (GIT). This study allows to understand that the combination of LPxTG-motif surface proteins (LMP) and fructooligosaccharides (FOS) can have a better promoting effect on lactic acid bacteria. In this study, molecular docking and molecular dynamics simulations were employed to investigate the interaction properties of LMP from Limosilactobacillus reuteri SH23 with small nutrient molecules in the host GIT. The thermodynamic parameters ΔG0, ΔH0, and ΔS0 were calculated as −4.850 kJ/mol, −219.071 kJ/mol, and −718.501 J/(mol∙K), respectively, for a binding constant of 1.414 × 104 μmol/L at 298.15 K. Fluorescence spectroscopy and circular dichroism spectroscopy were also utilised to study the interaction of LMP with the small nutrient molecules. It was found that LMP interacts with the small nutrient molecule FOS primarily through van der Waals and electrostatic forces. The transition from β-folding and random coiling to α-helix and β-sheet also indicates structural changes in the protein during the binding process. Furthermore, the binding of LMP to FOS not only improved the adhesion of the strain to intestinal epithelial cells and increased the auto-aggregation of the strain, but also promoted the growth of L. reuteri SH23. These findings provide a better understanding of Lactobacillus and host interactions at the cell surface protein level.

内容: In this study, the different powers (100−500 W) of high intensity ultrasound (HIU) were configured to investigate the mechanism of action on the tropomyosin (TM) structure, immunoglobulin G (IgG) binding capacity and digestive properties in oyster. The α-helix content of the HIU-treated TM decreased from 75.3% (control) to 41.8% (500 W) with the conversion of α-helix to random coil in TM molecules. The tertiary structure was changed with the decrease of particle size (from 165.5 to 85.6 nm) and the variety in aggregation state. Remarkably, the IgG binding capacity of TM decreased resulting from the higher power HIU treatment (300−500 W). After gastrointestinal digestion, the binding capacity of TM to IgG decreased to 1.31 with 500 W treatment, while the digestibility significantly increased. Overall, the present study suggested that the HIU-induced structural changes contributed to improving in vitro digestibility and reducing IgG binding capacity. This study contributes significant potential in terms of oyster allergen reduction.

内容: Diabetic cardiomyopathy (DCM) refers diabetic patients develop cardiomyopathy characterized by cardiac systolic and diastolic dysfunction. Currently, no research has explored the role of ten-eleven translocation (TET)-mediated active DNA demethylation in the development of DCM. Through case-control study, we found that the level of 5-hydroxymethylcystein in peripheral blood DNA of DCM patients was significantly lower than it in the healthy subjects and diabetic patients. Secondly, we had conducted an animal study to explore the effect of thinned young apple polyphenol (TYAP) on DNA demethylation in streptococci-induced diabetic mice. TYAP effectively prevented the ventricular dysfunction and cardiomycyte disarray via alleviating DNA epigenetic modifications metabolic disorders in diabetic mice heart. TYAP increased the stability of TET2 protein via activating phosphorylate AMPK and enhanced the activity of TETs enzymes via improving tricarboxylic acid cycle, then promoted TET-mediated active DNA demethylation. TYAP prevented the occurrence of DCM by promoting TET2-mediated active DNA demethylation in the heart of diabetic mice.

内容: Consuming low-glycemic index foods, such as black highland barley (BHB), is essential for regulating post-meal glucose levels in individuals with type 2 diabetes mellitus (T2DM). This study examined how the starch structure of BHB affected glucose fluctuations. The incorporation of BHB enlarged starch granule size and modified the crystalline structure to an A + Ⅴ type with a relative crystallinity of 31.14%. This alteration facilitated a more organized release of glucose. Population-based trials lasting 6 weeks had demonstrated that that BHB could reduce glucose variation, ghrelin levels, and insulin resistance in T2DM. Additionally, it increased the populations of beneficial gut bacteria such as Akkermansia, Bifidobacterium, and Lactobacillus, while also raising levels of gastric inhibitory peptides, phenolics, and specific gut metabolites. The specific digestion protocol and mathematical model of BHB disclosed its slow gastric emptying and glucose release rates, which were crucial for maintaining stable glucose levels in individuals with T2DM. Understanding the starch structure of BHB provided an effective dietary intervention for managing T2DM-related glucose fluctuations.

内容: Black tea is a kind of full-fermented tea with therapeutic potential for metabolic diseases. Ectopic lipid deposition (ELD) is an essential risk factor for organ injury in metabolic syndrome, especially in liver and kidney, for which effective interventions are lacking. Here, we explored whether black tea extract (BTE) improves fatty liver and fatty kidney, as well as identified the potential lipid biomarkers for ELD and lipid targets of BTE on the improvement of ELD. Transcriptome data from diet-induced obese mice were analyzed to confirm high-fat-diet feeding disturbs lipid metabolism in the liver and kidney. BTE prominently inhibited body weight gain, improved glucose metabolism, as well as reduced lipid droplet accumulation in the liver and kidney. Moreover, lipidomic profiling analyses identified 28 lipid classes in the liver while 29 in the kidney with that up-regulated glycerides and phosphatidylcholines, as well as down-regulated cardiolipin were the characteristic changes in ELD. BTE prominently reduced glycerides in ELD, thereby constituting the basis of its anti-ELD effect. Specifically, BTE displayed stronger effects on lowering cholesterol ester (CE) in fatty liver, while also affecting phospholipids and sphingolipids in fatty kidney. Ultimately, integrative analysis identified CE18:2 and triglyceride (TAG)56:4 (20:2) as the potential lipid biomarkers for BTE in improvement of ELD. BTE could be an effective food supplement for the prevention and treatment of ELD. Notably, CE18:2 and TAG56:4(20:2), as the potential lipid biomarkers, may facilitate the research and development of anti-ELD drug.

内容: Phenylethanol glycosides (PhGs) constitute crucial bioactive compounds in Cistanche Herba. However, their bioavailability is notably low. Research indicates that intestinal flora can metabolize PhGs into small polyphenols, enhancing bioavailability and pharmacological activities. In this paper, for the first time, a single strain, Beauveria bassiana, was found to be effective in converting PhGs from the crude extract of Cistanche tubulosa into small molecule polyphenols like hydroxytyrosol (HT), decaffeoylacteoside (HT-glu-rha), and caffeic acid through fermentation. We assessed the impact of pre- and post-fermentation on Propionibacterium acnes-induced acne related to a western diet through in vitro cellular experiments. Both pre- and post-fermentation exhibited efficacy in inhibiting inflammation, oxidative stress, and mitochondrial membrane damage in P. acnes-induced HaCaT. Moreover, post-fermentation, unlike pre-fermentation, displayed stronger and a dose-dependent reduction in insulin-stimulated lipid synthesis in sebaceous gland cells. To further understand the increased efficacy of fermentation in inhibiting lipid synthesis, we investigated HT-glu-rha, the predominant small molecules produced during fermentation. It was shown that the compound inhibited lipid synthesis by decreasing gene expression of sterol regulatory element binding transcription factor 1 (SREBP-1) and peroxisome proliferator activated receptor gamma (PPARγ) in sebaceous gland cells.

内容: This study investigated the protective effect of ferulic acid (FA) on the digestibility of oxidized beef myofibrillar protein (MP). MP were treated with varying concentrations of FA (20, 40, and 80 μmol/g pro) and then exposed to oxidation. The results showed that FA inhibited carbonyl in a dose-dependent manner. Fluorescence spectroscopy and molecular docking studies revealed FA was bonded to MP via hydrophobic interactions and hydrogen bonds. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and transmission electron microscope analysis indicated that FA mitigated the aggregation of oxidized MP. Peptidomic analysis showed FA protected 34.24% peptides recover from oxidation loss, and theses recovered peptide were mainly distributed in hydrophobic regions and lysine sites. In vitro digestion showed FA remarkably improved digestibility of oxidized MP (P < 0.05), with 80 μmol/g pro FA mitigating 67.85% loss in digestibility. Overall, FA effectively preserved the release of peptides by inhibiting hydrophobic aggregation and oxidation of lysine residues, thereby alleviating the decrease in digestibility of oxidized MP.

内容: Changes in lipids in light salt dry-curing (LSD) grass carp muscle stored at 4 ℃ for 15 days were investigated to clarify the effect of LSD on lipid transformation. A total of 1265 lipid molecules from 35 subclasses were identified in the grass carp muscle. LSD promoted lipid conversion in early cold stage (0−6 days) but inhibited it later (6−15 days). Phosphatidylethanolamine (16:1e/22:6), phosphatidylcholine (16:0/20:4) and triacylglycerol (18:0/16:0/20:4) might be biomarkers of inhibited lipid corruption. The metabolisms of glycerophospholipid, fatty acids and arachidonic acid were crucial in restraining lipid transformations. Thiobarbituric acid reactive substances in LSD-pretreated muscle were significantly increased. LSD significantly increased acid lipase and phospholipase activities during early cold stage, but this effect decreased with refrigeration time. The lipid profile of LSD-pretreated grass carp muscle showed no significant change on day 15 of refrigeration. Consequently, LSD inhibited the lipid degradation of grass carp muscle during extended cold storage.

内容: Foodborne pathogens are the leading causes of human diseases that result in hundreds of thousands of deaths annually. Clostridium perfringens is a notorious foodborne pathogen of global significance that is known to produce a large repertoire of toxic factors, several of which can severely destroy the gut lining to lead to abdominal pain, diarrhea, and even death. However, like many other foodborne pathogens, there is no specific treatment for infections caused by C. perfringens and rehydration therapy is largely ineffective at reducing symptoms and preventing transmission. Given this, there is an urgent need to discover new therapeutic targets that can be harnessed to treat C. perfringens infection. We recently discovered that a highly toxic factor produced by C. perfringens named perfringolysin O (PFO) activates the innate immune sensor NLR family pyrin domain containing 3 (NLRP3). We characterized that PFO is the specific agonist of NLRP3 inflammasome and mechanistically, the intracellular entrance of PFO is required for active assembly of NLRP3 inflammasome. Further, PFO targets the mitochondria resulting in mitochondrial destabilization and reactive oxygen species (ROS) release. Mito-TEMPO scavenging mitochondrial ROS (mtROS) specifically inhibits the level of Caspase-1 p20 and interleukin (IL)-1β in both in vitro and in vivo models. Additionally, 5-hydroxydecanoate (5-HD), a selective mitochondrial ATP-sensitive potassium channel (KATP) inhibitor, could relieve PFO-induced NLRP3 inflammasome activation as well as mitochondrial destabilization, indicating that potassium ion flux is necessary for mitochondrial damage upstream of NLRP3 inflammasome activation. We expect that the information gathered from this study will develop insights into features of the immune response that can be targeted for the treatment of food poisoning and other foodborne pathogenic infections.

内容: This study investigated the effects of cinnamaldehyde on putrescine production by Obesumbacterium proteus in pure cultures and Xinjiang sausage. Scanning electron microscopy was used to analyze the cell morphology of the test bacteria, and reverse transcription real-time fluorescence quantitative polymerase chain reaction was employed to analyze the gene expression of arginine decarboxylase and ornithine decarboxylase of the test bacteria at different cinnamaldehyde concentrations. Single-molecule real-time sequencing was utilized to identify the species composition of the sausage. Moreover, relevant parameters such as putrescine accumulation and microbial growth were evaluated. The results indicated that cinnamaldehyde inhibited the growth of O. proteus by leaking its contents and changing membrane permeability, and significantly reducing putrescine accumulation by inhibiting the expression of arginine decarboxylase (adiA) and ornithine decarboxylase (speF) genes. The cinnamaldehyde concentration revealed an inverse relationship between gene expression and putrescine accumulation. Besides, cinnamaldehyde significantly reduced the abundance of harmful bacteria (Enterobacteriaceae and Pseudomonas), alleviate putrescine content and stimulate the release of amino acids in the sausage. Therefore, adding cinnamaldehyde is an effective method to inhibit putrescine accumulation and reduce the growth of spoilage microorganisms in the sausage.