Efficient mitigation of lithium dendrite by two-dimensional A-type molecular sieve membrane for lithium metal battery.

Uneven lithium deposition poses a primary challenge for lithium-ion batteries, as it often triggers the growth of lithium dendrites, thereby significantly compromising battery performance and potentially giving rise to safety concerns. Therefore, the high level of safety must be guaranteed to achieve the large-scale application of battery energy storage systems. Here, we present a novel separator design achieved by incorporating a two-dimensional A-type molecular sieve coating onto the polypropylene separator surface, which functions as an effective lithium ion redistribution layer. The results demonstrated that even after undergoing 1000 cycles, the cell equipped with a two-dimensional A-type molecular sieve-Polypropylene (2D-A-PP) separator still maintains an impressive capacity retention rate of 70 %. In contrast, cells equipped with Polypropylene (PP) separators exhibit capacity retention rates below 50 % after only 500 cycles. Additionally, the incorporation of a two-dimensional molecular sieve enhances the mechanical properties of the PP separator, thereby bolstering battery safety. This study proposes a novel concept for the design of lithium-ion battery separator materials, offering a fresh perspective on the development of separators with exceptional thermal stability, enhanced porosity, superior electrolyte affinity, and effective inhibition of lithium dendrite formation.

Dexmedetomidine Improves Long-term Neurological Outcomes by Promoting Oligodendrocyte Genesis and Myelination in Neonatal Rats Following Hypoxic-ischemic Brain Injury.

Neonatal hypoxic-ischemic brain injury (HIBI) can lead to white matter damage, which significantly contributes to cognitive dysfunction, emotional disorders, and sensorimotor impairments. Although dexmedetomidine enhances neurobehavioral outcomes, its impact on oligodendrocyte genesis and myelination following hypoxic-ischemic events, as well as the underlying mechanisms, remain poorly understood. Dexmedetomidine was administered 15 min post-HIBI. We assessed neurobehavioral deficits using various tests: surface righting, negative geotaxis, forelimb grip strength, cliff avoidance, sensory reflexes, novel object recognition, T-maze, and three-chamber social interaction. We also investigated the relationship between myelination and neurobehavioral outcomes. Measurements included oligodendrocyte precursor cell (OPC) proliferation and survival 24 h post-injury, early myelination, and oligodendrocyte differentiation by postnatal day 14. Furthermore, we evaluated microglial activation towards the M2 phenotype and the extent of neuroinflammation during the acute phase. Dexmedetomidine significantly ameliorated long-term neurological deficits caused by HIBI. Pearson linear regression analysis revealed a strong correlation between long-term neurological outcomes and myelin maturity. The treatment notably mitigated the long-term deterioration of myelin formation and maturation following HIBI. This protective effect was primarily due to enhanced OPC proliferation and survival post-HIBI during the acute phase and, to a lesser extent, to the modulation of microglial activity towards the M2 phenotype and a reduction in neuroinflammation. Dexmedetomidine offers substantial protection against long-term neurobehavioral disabilities induced by HIBI, primarily by revitalizing the impaired survival and maturation of oligodendrocyte progenitor cells and promoting myelination.

GC-MS-based metabonomic analysis of silkworm haemolymph reveals four-stage metabolic responses to nucleopolyhedrovirus infection.

Silkworm, Bombyx mori, an economically significant insect, plays a crucial role in silk production. However, silkworm breeding is highly susceptible to various pathogens, particularly the Bombyx mori nucleopolyhedrovirus (BmNPV), which poses a serious threat. Recent metabonomic studies have provided insights into the metabolic changes associated with BmNPV infection. BmNPV infection has obvious temporal characteristics. However, few studies have investigated the silkworms infected in different periods. This study employed gas chromatography-mass spectrometry (GC-MS) to perform a comprehensive analysis of haemolymph metabolites in silkworms at 48, 72, 96 and 120 h post-infection (h.p.i.). Through the integration of time-course analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, the study revealed distinct four-stage metabolic characteristics in the silkworm's response to BmNPV infection. At Stage 1 (48 h.p.i.), silkworms activate antioxidant defence mechanisms, with significant enrichment in metabolic pathways involving key antioxidants such as glutathione, to mitigate oxidative stress induced by viral invasion. By Stage 2 (72 h.p.i.), pathways related to amino acid metabolism and protein synthesis become active, indicating an increase in protein synthesis. In Stage 3 (96 h.p.i.), energy metabolism and substance transport pathways are significantly upregulated to support the rapid viral replication and the enhanced locomotor behaviour of silkworm. Finally, at Stage 4 (120 h.p.i.), there is a further enhancement of pathways related to energy metabolism, nucleic acid synthesis, and substance transport, which align with peak viral assembly and release. These findings contribute to an in-depth understanding of the biochemical basis of silkworm resistance to NPV.

Synergetic spin crossover and fluorescence in a mononuclear iron(III) complex.

Two mononuclear iron(III) complexes (XEA)[Fe(azp)2]·H2O (H2azp = 2,2'-azodiphenol, XEA = 2-fluoroethylammonium and 2-chloroethylammonium) are synthesized, which exhibit the counterion dependence of magnetic and fluorescent properties. The synergetic effect between abrupt spin crossover and fluorescence is observed in an iron(III) complex for the first time.

PCSK9 inhibitor protects against myocardial ischemia-reperfusion injury via inhibiting LRP8/GPX4-mediated ferroptosis.

Myocardial ischemia-reperfusion injury is accompanied by ferroptosis mediated by reactive oxygen species and iron ions, which aggravates myocardial tissue damage. The present study aims to explore the molecular mechanism underlying the mitigating effects f PCSK9 on myocardial ischemia-reperfusion injury. MI/R rat model and OGD/R induced H9c2 model were established. The interaction between PCSK9 inhibitor and LRP8 was predicted by STRING database and verified by Immunoprecipitation assay experiment. CCK-8 kit results confirmed that PCSK9 inhibitor effectively protected against cardiomyocyte damage induced by OGD/R. TTC and histological examination via H&E staining revealed a significant alleviation of myocardial infarction and pathological alterations upon treatment with the PCSK9 inhibitor. Besides, DCFH-DA staining and biochemical kit results showed that PCSK9 inhibitor could regulate the changes of ferroptosis related indicators [ROS, iron level, MDA, SOD] and inhibit ferroptosis. Rescue experiments showed that PCSK9 inhibitors targeted LRP8 expression and inhibited GPX4/ROS-mediated ferroptosis in I/R-induced rats. Our study suggested that PCSK9 inhibitors could attenuate myocardial I/R injury, with the underlying mechanism intimately tied to the targeted modulation of LRP8/GPX4-mediated ferroptosis.

In vivo and in vitro reconstitution of biosynthesis of N-prenylated phenazines revealing diverse phenazine-modifying enzymes.

Phenazine natural products play various roles such as signal molecules, antibiotics, or electron carriers in their producer strains. Among these products, phenazinomycin and lavanducyanin, which are produced by Streptomyces species, are characterized by an N-alkyl modification. Herein, we established the biosynthetic pathways for these two phenazine natural products. Gene-disruption experiments and in vitro reconstitution of the phenazine-tailoring pathway revealed the late steps of the biosynthetic pathway of the phenazines. The class II terpene cyclase homolog Pzm1 catalyzes the cyclization reaction of farnesyl diphosphate to form monocyclic farnesyl diphosphate. Additionally, the prenyltransferase homolog PzmP functions as the N-prenyltransferase of 5,10-dihydrophenazine-1-carboxylic acid. The flavin monooxygenase homolog PzmS catalyzes the oxidative decarboxylation of prenylated 5,10-dihydrophenazine-1-carboxylic acid to yield phenazinomycin. This study highlights unprecedented modification enzymes for phenazine natural products.

Role and clinical value of serum hsa_tsr011468 in lung adenocarcinoma.

Transfer RNA­derived small RNAs (tsRNAs) are novel non­coding RNAs that are associated with the pathogenesis of various diseases. However, their association with lung adenocarcinoma (LUAD) has not been studied comprehensively. Therefore, the present study aimed to explore the diagnostic value of a tsRNA, hsa_tsr011468, in LUAD. The OncotRF database was used to screen tsRNAs and reverse transcription­quantitative PCR (RT­qPCR) was performed to detect the expression levels of hsa_tsr011468 in various samples. Subsequently, the diagnostic and prognostic values of hsa_tsr011468 for LUAD were determined via receiver operating characteristic (ROC) curve and survival curve analyses, and by assessing clinicopathological parameters. In addition, both nuclear and cytoplasmic RNA were extracted to assess the location of hsa_tsr011468. The OncotRF database identified high expression of hsa_tsr011468 in LUAD. In addition, the results of RT­qPCR showed that the relative expression levels of hsa_tsr011468 in the serum and tissues of patients with LUAD were higher than those in normal controls. Furthermore, its expression was lower in postoperative serum samples than in preoperative serum samples from patients with LUAD. ROC and survival curves indicated that hsa_tsr011468 had good diagnostic and prognostic value. Furthermore, the clinicopathological analysis revealed that hsa_tsr011468 was associated with tumor size. In addition, hsa_tsr011468 was mainly localized in the cytoplasm of LUAD cells. The present study indicated that hsa_tsr011468 has good diagnostic value and, therefore, could be employed as a serum marker for LUAD.

Transcriptomic Analysis of Genes Associated with Stinger Development at Different Life Stages of Apis mellifera.

Stingers, evolved from ovipositors, are an important defense organ for the Apidae, Vespidae, and Formicidae species. However, the molecular mechanism of stinger development remains unclear. Here, we show that the earliest time point for the appearance of stingers in Apis mellifera is at the 1-day-old worker pupal stage based on morphological observations and anatomy from the pre-pupal to adult stages. To discover the genes related to stinger development, we first comprehensively compared the stinger transcriptome at different stages and screened 1282, 186, and 166 highly expressed genes in the stingers of 1- and 5-day-old worker pupae and newly emerged worker bees (NEBs), respectively, then identified 25 DEGs involved in the early stage of stinger development. We found that Dll was a key candidate gene in the early development of A. mellifera stingers by combining analyses of the protein-protein interaction network and spatiotemporal expression patterns. An RNAi experiment showed that about 20% of individuals exhibited tip bending in the piercing parts of their stingers in the Dll-dsRNA-treated group, with the morphology presenting as side-side or front-back tip bending. This indicates that Dll plays a vital role in the early development of A. mellifera stingers. Together, our study provides insight into the molecular mechanism of Hymenoptera stinger development and an inspiration for the molecular breeding of gentle honeybee species with stinger abnormalities.

Investigation of the Inhibitory Activity of ß-Arbutin and Its Analogues on Tyrosinase Based on Molecular Docking and Enzyme Inhibition Kinetics.

ß-Arbutin, a natural glucoside hydroquinone derivative known for its skin-whitening properties through tyrosinase inhibition in melanin synthesis, may pose potential risks of allergy and carcinogenicity due to the release of hydroquinone during use. This study explores the inhibitory effects of phenyl-ß-D-pyranoglucoside (compound 1), 4-methoxyphenyl-ß-D-pyranoglucoside (compound 2), 4-hydroxymethylphenyl-ß-D-pyranoglucoside (compound 3), and ß-arbutin (compound 4) on tyrosinase using enzyme kinetics, molecular docking, and molecular dynamics simulations. Results show compounds 1, 3, and 4 exhibit competitive inhibition, while compound 2 shows mixed inhibition. Docking analysis reveals phenyl rings of all compounds interact with the enzyme's active site, with compound 3 forming a metal bond with copper ions. MD simulations indicate high stability for compounds 2, 3, and 4, with compound 3 showing the lowest RMSD and compact Rg, suggesting stronger binding. Compound 1 is less stable and less inhibitory. These insights are valuable for designing effective tyrosinase inhibitors.

Systemic Epstein-Barr virus-positive T-cell lymphoma of childhood combined with hemophagocytic lymphohistiocytosis: a case report.

Background: Systemic Epstein-Barr virus (EBV)-positive T-cell lymphoma of childhood (STCLC) is a rare disease with few clinical reports and high mortality. By exploring the clinical manifestations of a child with STCLC in our hospital auxiliary examination and diagnostic and therapeutic process, to deepen pediatricians' understanding of this disease. Case Description: This paper describes a 5-year-old Chinese girl who presented with acute fever and epistaxis. After admission, relevant ancillary tests indicated the presence of hemophagocytic lymphohistiocytosis (HLH) and the combination of EBV infection in this patient. Pathology of the cervical lymph node biopsy and bone marrow flow cytology examination indicated STCLC, and a diagnosis of STCLC combined with HLH was clear. Although the girl was clearly diagnosed within a few days and treated with chemotherapy and symptomatic support, she eventually died on the 6th day after admission due to progressive worsening of her disease. Conclusions: STCLC is a rare T-cell lymphoproliferative disorder that occurs primarily in the setting of acute EBV infection, usually presenting as HLH. It is a rapidly progressive and fatal disease of children and young adults characterized by monoclonal expansions of EBV-positive T-cells with an activated cytotoxic phenotype and by malignant proliferation. The mortality rate is close to 100%.

Halogen-Driven Single-Crystal to Single-Crystal Transformation Engineering the Cluster-based Spin Crossover Frameworks.

Cluster-based spin crossover (SCO) frameworks are a new class of smart metal-organic frameworks (MOFs) with diverse structures and topologies and unique bistable physicochemical properties. Here, we report a cluster-based SCO framework [Fe3{Ag4(CN)6(H2O)}2(TPBA)3](ClO4)2·7DMF (1) with an extremely rare 3,4,6-T108 topology, in which the tripodal [Ag{Ag(CN)2}3(H2O)]2- clusters axially link the Fe2+ ions to form 2D→3D n-fold Borromean entangled networks. Under the guidance of reticular chemistry, the post-synthetic modification (PSM) from 1 with 3,4,6-T108 topology to [Fe3{Ag8X8(CN)6}(TPBA)3] (2_X, X = Cl, Br, I) with urk topology is firstly achieved via single-crystal to single-crystal (SCSC) transformation. Moreover, the successive SCSC transformations from 2_Cl to 2_Br and then to 2_I are realized for the first time. Their SCO behaviors are also modified by halogen-driven stepwise cluster transformations. Hence, these findings provide new strategies for the development of cluster-based SCO MOFs towards the smart functional porous materials.

Bifunctional Photothermal Evaporator Based on an MXene/Fe-MOF Collaborative Effect toward Efficient Solar Steam Generation and Simultaneous VOC Removal.

Solar-driven interfacial water evaporation has become one of the most promising approaches to effectively harvesting freshwater, yet the fabrication of high-performance and multifunctional solar interfacial evaporators (SIEs) still remains a huge challenge to date. In this study, a multifunctional MXene and Fe-MOF@cellulose acetate/polyvinylpyrrolidone (MXM@CP) SIE was prepared via a facile "electrospinning and suction filtration deposition" coupling strategy. Thanks to the incorporation of MXene, MXM@CP displayed excellent photothermal conversion performance. Together with the fast water transport channel provided by the porous cellulose acetate electrospinning substrate, a remarkable solar-driven water evaporation property was achieved for MXM@CP, showing a higher water evaporation rate of 1.1 kg m-2 h-1 under one sun irradiation. Moreover, the resultant composite film also exhibited excellent Fenton catalytic activity to effectively degrade volatile organic compounds (VOCs) due to the synergistic effect of the MXene and Fe-based MOF (Fe-MOF). Particularly, a relatively higher degradation rate of 82.8% was acquired for the resulting evaporator toward the benzene contaminant. These results provide new insights into the construction of high-performance and multifunctional SIEs toward clean freshwater collection from the VOC-contaminated water system.

Pathologic Response of Phase III Study: Perioperative Camrelizumab Plus Rivoceranib and Chemotherapy Versus Chemotherapy for Locally Advanced Gastric Cancer (DRAGON IV/CAP 05).

PURPOSE: This multicenter, randomized phase III trial evaluated the efficacy and safety of perioperative camrelizumab (an anti-PD-1 antibody) plus low-dose rivoceranib (a VEGFR-2 inhibitor) and S-1 and oxaliplatin (SOX) (SOXRC), high-dose rivoceranib plus SOX (SOXR), and SOX alone (SOX) for locally advanced gastric or gastroesophageal junction (G/GEJ) adenocarcinoma. METHODS: Patients with T3-4aN + M0 G/GEJ adenocarcinoma were randomly assigned (1:1:1) to receive perioperative treatment with SOXRC, SOXR, or SOX. The primary end points were pathologic complete response (pCR) and event-free survival. The Independent Data Monitoring Committee recommended stopping enrollment in the SOXR group on the basis of the safety data of the first 103 randomly assigned patients in the three groups. The patients were then randomly assigned 1:1 to the SOXRC or SOX groups. This report presents the pCR results obtained per protocol for the first 360 randomly assigned patients who had the opportunity for surgery in the SOXRC and SOX groups. RESULTS: In the SOXRC and SOX groups, of the 180 patients in each group, 99% and 98% of patients received neoadjuvant therapy, 91% and 94% completed planned neoadjuvant therapy, and 86% and 87% underwent surgery, respectively. The pCR was significantly higher in the SOXRC group at 18.3% (95% CI, 13.0 to 24.8) compared with 5.0% (95% CI, 2.3 to 9.3) in the SOX group (difference of 13.7%; 95% CI, 7.2 to 20.1; odds ratio of 4.5 [95% CI, 2.1 to 9.9]). The one-sided P value was <.0001, crossing the prespecified statistical significance threshold of P = .005. Surgical complications and grade ≥3 neoadjuvant treatment-related adverse events were 27% versus 33% and 34% versus 17% for SOXRC and SOX, respectively. CONCLUSION: The SOXRC regimen significantly improved pCR compared with SOX alone in patients with G/GEJ adenocarcinoma with a tolerable safety profile.

Seven undescribed compounds from dried flower buds of Ochrocarpus longifolius.

Seven unreported compounds were isolated from dried flower buds of Ochrocarpus longifolius in this study, including an alkaloid ochrocaracid A (1), five coumarins ochrocarpins I (2), J (3), K (4), L (5), and M (6), and one styryl-2-pyranone compound iresinoacid (7) and nine known compounds (8-16). All these compounds were found in O. longifolius for the first time. Their structural elucidation was achieved through NMR, HR-ESI-MS, and ECD data. Additionally, a glucose uptake-promoting activity assay revealed that compounds 10 (128.21 µM) and 16 (123.15 µM) increased the glucose uptake capacity of L6 cells by 1.49-fold and 1.48-fold, respectively. These bioactive compounds could be potential candidates for further pharmaceutical applications.

A mutation in the Bombyx mori BmSPI51 gene results in alterations protein abundance in cocoon and unveils compensatory mechanism of silk gland proteinase inhibitors.

Proteinase inhibitors constitute a significant component of Lepidoptera cocoon. BmSPI51 is the most abundant protease inhibitors in silkworm cocoons. In this study, we aimed to elucidate the biological function of BmSPI51 in both the silkworm silk gland and cocoon formation. To achieve this, we utilized CRISPR/Cas9 gene editing to target the BmSPI51 gene, resulting in premature termination of translation at the 33rd amino acid residue. The mutation of BmSPI51 did not affect the growth and development. Nevertheless, it led to a substantial decrease in the economic traits of silkworm cocoons. Proteomic analysis indicated the abundance of fibroin heavy chain (Fib-H), fibroin light chain (Fib-L), and fibrohexamerin (P25) decreased significantly in the homozygous mutants. Further analysis of cocoon proteins found that the mutants significantly increased the secretion of other protease inhibitors in order to deal with the increased environmental stress resulting from the absence of BmSPI51. Surprisingly, homozygous mutant cocoons exhibited an enhanced inhibitory ability against Saccharomyces cerevisiae compared to the WT cocoons. In conclusion, our study provides a valuable insight into the biological function of protease inhibitors and revealed their roles in cocoon formation and potential applications in biotechnology.

The value of tissue quantitative diffusion analysis of ultrasound elastography in the diagnosis of early-stage chronic kidney disease.

PURPOSE: To explore the value of tissue quantitative diffusion analysis of ultrasound elastography in the diagnosis of early-stage chronic kidney disease (CKD). METHODS: The observation group comprised 54 patients with early-stage CKD treated at Fuzhou No 7 Hospital, and the control group consisted of 40 healthy individuals who underwent physical examinations at the same hospital. The renal parenchyma of the participants were examined using ultrasonography, color Doppler ultrasonography, and tissue quantitative diffusion analysis of ultrasound elastography. Renal dimensions (diameter, thickness, and renal parenchyma thickness), interlobar artery blood flow parameters, and 11 elastic characteristic values were analyzed and compared between the two groups. The area under the receiver-operating characteristic (ROC) curve, cut-off values, sensitivity, and specificity were calculated using the ROC curve analysis. RESULTS: There were no significant differences in the blood flow parameters of the interlobar artery and the dimensions of renal meridians between the two groups. In the observation group, the mean (MEAN) decreased, while the blue area ratio and skewness, increased, compared to the control group (p < 0.05). In addition, the ROC curve revealed that the blue area ratio, MEAN, and skewness had significant diagnostic value (the area under the curve > 0.7). Notably, the best cut-off value of the MEAN was found to be 106, indicating that a MEAN value less than 106 represented early-stage CKD. Also, this cutoff value had a sensitivity of 80% and a specificity of 81%. CONCLUSION: Tissue quantitative diffusion analysis of ultrasound elastography can quantitatively evaluate renal parenchymal damage in early-stage CKD using quantitative diffusion parameters, with the MEAN parameter, having a cutoff of 106, being particularly effective. This parameter and cutoff value offer a valuable tool for the early detection and diagnosis of CKD, potentially improving patient outcomes through earlier intervention. CLINICAL TRIAL NUMBER: Not applicable.

Conserved responses of water use to evaporative demand in mixed forest across seasons in low subtropical China.

The positive correlation between diversity and production has been extensively documented. Given the intrinsic relationship between production and plant water consumption, it was anticipated that mixed forests would exhibit different water use compared to pure forests. In this study, the responses of water use to vapour pressure deficit were analyzed by monitoring the sap flow of Schima superba in both pure and mixed forests, as well as Castanopsis chinensis in mixed forest. Additionally, the relationships among leaf and stem traits were examined by measuring specific leaf area (SLA), N and P concentration per unit leaf mass, leaf δ18O and δ13C and wood density of sapwood (WD) during both wet and dry seasons. The results showed that S. superba demonstrated a comparable regulation of water use during both wet and dry seasons in mixed forest, whereas it exhibited less strict water use regulation during the wet season in comparison to the dry season in pure forest. Regardless of whether the forests were pure or mixed, both leaf δ13C and WD remained consistent across seasons, while there was an increase in SLA during the wet season compared to the dry season for S. superba. There was a different seasonal change in leaf δ18O for S. superba in pure and mixed forests. Water use and leaf economic spectrum may determine the adaptive strategies of coexisting species, and the coexisting tree species in mixed forest exhibited a resource-use differentiation, as indicated by seasonal variations in leaf and stem traits, likely explaining the conserved responses of sap flow to evaporative demand. Our research might provide insights into the impact of tree interaction on water use strategies and the water use-based forest management under current climate change.

[NF-κB transcription factors regulate the expression of immunity-related genes in different cell lines of silkworm (Bombyx mori)].

The Toll and immune deficiency (IMD) signaling pathways in insects are highly conserved in evolution and regulate the expression of antimicrobial peptides (AMPs) and other immune-related genes mainly through nuclear factor-kappa B (NF-κB) transcription factors. However, the differences of NF-κB transcription factors Rels and Relish in the expression regulation of AMPs and other immune-related genes in silkworm (Bombyx mori) have not been systematically reported. In this study, the BmRelA, BmRelB and BmRelish1 genes were cloned and their eukaryotic cell overexpression vectors were constructed. After the recombinant vectors were transfected into BmE and BmN cells, the expression of AMPs and immune-related genes was detected by real-time fluorescence quantitative PCR. The results showed that the expression of AMP genes Defensin2 and Gloverin2 was mainly regulated by Relish, the expression of Moricin was mainly regulated by RelA and RelB, and the expression of other AMP genes was jointly regulated by both. In addition, the expression levels of peptidoglycan recognition proteins (PGRPs), ß-1, 3-glucan recognition proteins (ßGRPs), lysozymes (Lys) and lysozyme-like proteins (LLPs), and nitric oxide synthase (NOS) were up-regulated to varying degrees in different cell lines in response to RelA, RelB and Relish1, suggesting that the expression of these immune-molecules was also regulated by Toll or IMD pathways in silkworm. Compared with the regulatory specificity of transcription factors in Drosophila Toll and IMD signaling pathways on the expression of AMPs, this study found that the regulatory patterns of Rels and Relish1 on the expression of AMPs in silkworm are more complex, which provides an experimental basis for further analysis of the effect mechanism and feedback mechanism of Toll and IMD pathways in insects.

Taste characterization and molecular docking study of novel umami flavor peptides in Yanjin black bone Chicken meat.

Five polypeptides with a potential umami taste were isolated and purified from Yanjin black bone chicken. However, the flavor characteristics and umami mechanism have not been clarified. The umami properties of these five peptides were investigated in this work using a range of analytical techniques, computer simulation, and sensory evaluation. HE-10 and TP-7 exhibited the strongest umami flavors. Furthermore, dose-response experiments showed that the umami peptides enhanced umami by generating peptide mineral chelates. Environmental scanning electron microscopy (ESEM) microstructural analyses supported this finding. The molecular docking results indicated that the five polypeptides bind to four critical amino acid residues, namely Glu217, Glu148, Asp216, and His145, of the T1R1/T1R3 receptor. The binding occurred through van der Waals, electrostatic interactions, hydrogen bonding, and hydrophobic interactions. The main surface forces implicated include aromatic interactions, hydrogen bonding, hydrophilicity, and solvent accessibility.