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关键词： 1-kestose   Fructooligosaccharides   Immobilization   Komagataella phaffii   Levansucrase   Prebiotics  

摘要： Fructooligosaccharides (FOS) are widely recognized prebiotics that selectively stimulate beneficial gut microbiota. Among short-chain FOS, 1-kestose has been reported to exert superior bifidogenic activity compared to longer-chain oligosaccharides, and its enrichment in FOS mixtures is increasingly valued for therapeutic and nutritional applications. However, industrial production of FOS from sucrose often results in mixtures contaminated with residual sucrose and glucose, which diminish prebiotic efficacy and limit use in populations with metabolic disorders. To address this, we developed a recombinant Komagataella phaffii strain expressing a mutated levansucrase (LsdA R171K–H172S) from Gluconoacetobacter diazotrophicus for the synthesis and purification of FOS. Fed-batch culture experiments revealed an imbalance between periplasmic retention and extracellular secretion of the enzyme, despite the presence of a secretion signal. To overcome this limitation, cells were immobilized in calcium alginate beads, enabling simultaneous sucrose hydrolysis and glucose consumption. Optimal biomass loading was determined to be 300 g/L, balancing enzymatic activity and bead stability. Semicontinuous purification was performed in a fixed column at 35 °C with varying carbohydrate concentrations. The highest FOS purity (91.8%) and recovery (90.5%) were achieved at 400 g/L carbohydrate concentration. The resulting solution contained predominantly 1-kestose (79.9%) with 20% nystose, and negligible residual sucrose or glucose. This one-step bioprocess demonstrates an efficient strategy for producing high-purity FOS enriched in 1-kestose, offering advantages over conventional fermentation and purification methods and supporting the development of functional foods with enhanced prebiotic potential.

关键词： 2D MBenes   Anode material   Calcium-ion batteries   Electrochemical performance  

摘要： Calcium-ion batteries (CIBs) are widely regarded as promising alternatives to lithium-ion batteries (LIBs) due to their abundant resources, low-cost, superior safety, high energy density and similar working mechanism; nevertheless, the absence of an exceptional anode material remains a notable obstacle impeding the advancement of CIB technology. In this work, we implemented a through first-principles calculation to estimate the anodic behavior of the emerging 2D TiB_x (x = 1-5) monolayers in CIBs. The projected band structure calculation reveals that the TiB_x (x = 1-5) anodes exhibit remarkable electronic conductivity with intrinsical metallic/semimetallic behavior. It is found that Ca ions are chemically anchored on the surfaces of TiB_x (x = 1-5) anodes with adsorption energies of −3.40 to −0.25 eV. Moreover, the lightweight properties and high affinity of Ca ions endow TiB_x (x = 1-5) anodes with low average open-circuit-voltages of 0.20, 0.43, 0.45, 0.45 and 0.45 V, as well as high theoretical capacities of 608.98, 1028.48, 667.52, 1176.64 and 1051.84 mA h/g. Additionally, Ca ion can diffuse rapidly across the TiB_x (x = 1, 3, 4, 5) anode surfaces with diffusion barriers of 0.20, 0.27, 0.37 and 0.21 eV. In contrast, the TiB₂ anode exhibits a remarkably high diffusion barrier (1.00 eV) for Ca ion, resulting in a low ion mobility. Furthermore, TiB_x (x = 1-5) anodes present small volume expansion during electrochemical cycling with the maximum lattice changes of 3.59%, 4.97%, 1.34%, 4.42% and 1.91%. These exceptional attributes make TiB_x (x = 1, 3, 4, 5) monolayers appealing anode candidates for CIBs. In particular, the TiB₄ anode exhibits the optimal electrochemical performance due to its planar structure and high adsorption energy.

关键词： Sn-1,3 diacylglycerol   Acyl chain length   In vitro digestion   Lipolysis kinetics   Molecular docking   TAG   triacylglycerol   DAG   diacylglycerol   MAG   monoacylglycerol   FFA   free fatty acids   DDAG   decanoic diacylglycerol   LDAG   lauryl diacylglycerol   PDAG   palmityl diacylglycerol   SADG   stearyl diacylglycerol   NMR   nuclear magnetic resonance   CLSM   Confocal laser scanning microscopy   DSC   differential scanning calorimetry   SCFAs   short chain fatty acids   MCFAs   medium chain fatty acids   LCFAs   long chain fatty acids  

摘要：

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  A multi-scale mechanism was established from physical state to molecular interactions.
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  The strong binding affinity between lipase and substrate limited digestion efficiency.
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  The digestion rate of sn-1,3 DAG exhibited an inverse correlation with chain length.

关键词： 1-Propanol   Culture-dependent validation   Environmental factors   Metabolic pathways   Metagenomics   Microbial community  

摘要： 1-Propanol is a crucial flavor compound in Jiang-flavor Baijiu, yet the key microbial pathways and environmental factors controlling its synthesis have not been systematically investigated. Using an integrated approach of metagenomics and culture-dependent techniques, this study identified the key microbes, pathways, and factors controlling 1-propanol synthesis. The highest 1-propanol level was detected in first-round base Baijiu, with rapid accumulation during early pit fermentation. Metagenomics revealed the propanoate pathway as the dominant route, primarily contributed by Limosilactobacillus, while Pichia and Saccharomyces were key providers of pyruvate decarboxylase in the citramalate and threonine pathways. Pure-culture validation confirmed that L. panis MR32 predominantly utilizes 1,2-propanediol as the precursor, while yeasts such as P. kudriavzevii 2J2 and S. cerevisiae LB7A prefer the 2-ketobutyrate pathway. Environmental tests revealed optimal 1-propanol production by L. panis MR32 at pH 5.5 and increasing yields with temperature (25–45 °C). In contrast, most yeasts produced the most 1-propanol at 30 °C, beyond which yields declined, with only P. kudriavzevii 2J2 and I. orientalis IO tolerating high lactic acid. Our findings clarify the microbial division of labor and environmental drivers of 1-propanol formation, enabling targeted fermentation control.

摘要： The meta-selective trifluoromethylation of pyridines has remained a significant challenge due to the inherent electronic constraints of the aromatic system. This study developed a novel dearomatization-rearomatization strategy based on 1,4-dihydropyridinephosphonate intermediates, which underwent copper-catalyzed regioselective C–CF₃ bond formation with Togni II reagent followed by DABCO-promoted rearomatization, achieving highly regioselective meta-C-H trifluoromethylation of pyridine derivatives. This approach accommodated mostly meta-substituted pyridine substrates and enabled late-stage meta-C-H trifluoromethylation of pharmaceutical molecules containing pyridine motifs.

关键词： Agrimoniin   Angiogenesis   Glycolysis   Hepatopulmonary syndrome   Mitochondrialdysfunction   PGC-1α  

摘要： Hepatopulmonary syndrome (HPS) is a condition characterized by pulmonary angiogenesis and refractory hypoxemia, often seen in patients with chronic liver disease. Its unclear mechanism means that liver transplantation is the only effective therapy. Agrimoniin, a compound from Pilosa ledeb, shows potential in protecting against liver cirrhosis via anti-angiogenic and anti-glycolytic effects. This study investigates agrimoniin as a potential integrated therapy for HPS-related liver and lung dysfunction. Using transcriptome data and an ICU cohort, we analyzed the role of glycolysis in chronic liver disease progression. HPS rats were established via common bile duct ligation, and serum metabolites were measured. The oxygen consumption rate and extracellular acidification rate were also detected. Rats were treated with agrimoniin (3 mg/kg/day or 8 mg/kg/day) at the early stage of HPS. Our results showed that imbalanced oxidative phosphorylation and glycolysis correlated with chronic liver disease progression and poorer outcomes. Decreased oxygen consumption rate and increased extracellular acidification rate, as well as increased glycolysis, were observed in the HPS group. Agrimoniin treatment improved liver and lung function by inhibiting pathological angiogenesis and glycolysis. Through TCM suite analysis, molecular docking, and dynamics simulations, PGC-1α was identified as a potential target of agrimoniin. Inhibiting PGC-1α blocked agrimoniin's benefits on angiogenesis and glycolysis flux. Thus, agrimoniin may be a potential integrated therapy for HPS by activating PGC-1α to inhibit glycolysis and angiogenesis.

关键词： Boston KPro   Keratoprosthesis   glaucoma   intraocular pressure  

摘要： Boston Type 1 Keratoprosthesis (KPro) implantation is an established surgery for severe corneal blindness when traditional keratoplasty is not feasible. This systematic review and meta-analysis aimed to quantify the incidence and progression of glaucoma following KPro implantation.

关键词： ACM   all-cause mortality   cTnI   cardiac troponin-I   CV   cardiovascular   EQW   weekly exenatide   GLP-1   glucagon-like peptide-1   hHF   hospitalization for heart failure   HR   hazard ratio   MACE   major adverse cardiovascular event   NT-proBNP   N-terminal pro B-type natriuretic peptide   RCS   restricted cubic spline  

摘要： In the EXSCEL trial, exenatide did not reduce major adverse cardiovascular events (MACE), but heterogeneity of benefit and the role of cardiac biomarkers remain uncertain. We evaluated the prognostic value of baseline and 1-year changes in N-terminal pro B-type natriuretic peptide (NT-proBNP) and high-sensitivity cardiac troponin I (cTnI), and whether baseline biomarker concentrations modified exenatide effects.

关键词： Tin(IV) complexes   Lead(IV) complexes   Organotin(IV)   Organolead(IV)   Naphthalene-1,4-dione   Anthracene-9,10-dione  

摘要： In this paper, two proligands derived from the naphthalene-1,4-dione framework: 2-hydroxy-1,4-naphthoquinone, named lawsone (HL¹) and, 2-(2-(tosylamino)phenylamino)-3-chloro-naphthalene-1,4-dione, (H₂L²) were used to obtain tin(IV) compounds of formula [R₂SnL¹Cl], R = methyl (1), phenyl (2), [{Cp(CO)₂Fe}Sn(L¹)₂] (3) and [R₂SnL²], R = methyl (4) or Cp(CO)₂Fe (5). In order to increase the number of fussed rings, two new proligands containing the four fused 1H-anthra[1,2-d]imidazole-6,11-dione framework were also synthesized. H₂L³ incorporates a 2-hydroxyphenyl substituent on the imidazole ring and H₂L⁴ incorporates a 2-(tosylamino)phenyl group. Also tin(IV) compounds of formula R₂SnLⁿ, n = 3 or 4; R = methyl (6 and 8) or Cp(CO)₂Fe (7 and 9) were obtained. All the compounds were characterized by spectroscopic techniques, IR and ¹H NMR spectroscopy, and Mass spectrometry (FAB). The compounds [Me₂SnL²] (4), [{Cp(CO)₂Fe}₂SnL²] (5), and [{Cp(CO)₂Fe}₂SnL³] (7) were studied by single crystal x-ray diffraction and their structures are presented. For complex 2 we have obtained a new compound in the recrystallization process with CH₂Cl₂, because the coordinated 1,4-naphthoquinone-2-olate anion, (L¹)⁻, reacts with solvent to give a new ligand, the dianion of the 3,3′-methylene bilawsone, (L¹-CH₂-L¹)²⁻. The crystal structure of the [Ph₆Sn₄