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Black spot disease caused by Ceratocystis fimbriata is destructive to the production, transportation, and storage of sweet potato. The antifungal effects of Bacillus tequilensis XK29 against C. fimbriata through volatile organic compounds (VOCs) were evaluated in this study. The activated carbon assay proved that XK29 could exert antibiotic effects through volatiles. By optimizing the wheat seed weight, inoculation method, concentration, volume, and time, the antifungal activity of XK29 was significantly improved. XK29 fumigation inhibited spore formation and germination and changed the cell morphology of C. fimbriata. During the storage of sweet potato tuber roots, XK29 effectively controlled black spot disease and reduced the weight loss and malondialdehyde content. Metabolomic analysis revealed that 21 volatile compounds were released from XK29. Isovaleric acid, isobutyric acid, and 2-methylbutanoic acid effectively inhibited the growth of C. fimbriata. These results indicate that B. tequilensis XK29 has a good potential to be developed as a microbial fumigation agent.

4-Hydroxybenzoic acid (4-HBA) is a common organic compound that is prevalent in the environment, and the persistence of 4-HBA residues results in exertion of pollution-related detrimental effects. Bioremediation is an effective method for the removal of 4-HBA from the environment. In this study, two bacterial strains FZ-5 and FZ-8 capable of utilizing 4-HBA as the sole carbon and energy source under anaerobic conditions were isolated from marine sediment samples. Phylogenetic analysis identified the two strains FZ-5 and FZ-8 as Acinetobacter johnsonii and Klebsiella oxytoca, respectively. The strains FZ-5 and FZ-8 degraded 2000 mg·L−1 4-HBA in 72 h with degradation rates of 71.04% and 80.10%, respectively. The optimum culture conditions for degradation by the strains and crude enzymes were also investigated. The strains FZ-5 and FZ-8 also exhibited the ability to degrade other lignin-derived compounds, such as protocatechuic acid, cinnamic acid, and vanillic acid. Immobilization of the two strains showed that they could be used for the bioremediation of 4-HBA in an aqueous environment. Soils inoculated with the strains FZ-5 and FZ-8 showed higher degradation of 4-HBA than the uninoculated soil, and the strains could survive efficiently in anaerobic soil. This is the first report of 4-HBA-degrading bacteria, belonging to the two genera, which showed degradation ability under anaerobic conditions. This study expound the strains could efficiently degrade 4-HBA in anaerobic soil and will help in the development of 4-HBA anaerobic bioremediation systems.

Water nucleophilic attack (WNA) on high-valent terminal Mn-oxo species is proposed for O-O bond formation in natural and artificial water oxidation. Herein, we report an electrocatalytic water oxidation reaction with MnIII tris(pentafluorophenyl)corrole (1) in propylene carbonate (PC). O2 was generated at the MnV/IV potential with hydroxide, but a more anodic potential was required to evolve O2 with only water. With a synthetic MnV(O) complex of 1, a second-order rate constant, k2(OH-), of 7.4 × 103 M-1 s-1 was determined in the reaction of the MnV(O) complex of 1 with hydroxide, whereas its reaction with water occurred much more slowly with a k2(H2O) value of 4.4 × 10-3 M-1 s-1. This large reactivity difference of MnV(O) with hydroxide and water is consistent with different electrocatalytic behaviors of 1 with these two substrates. Significantly, during the electrolysis of 1 with water, a MnIV-peroxo species was identified with various spectroscopic methods, including UV-vis, electron paramagnetic resonance, and infrared spectroscopy. Isotope-labeling experiments confirmed that both O atoms of this peroxo species are derived from water, suggesting the involvement of the WNA mechanism in water oxidation by a Mn complex. Density functional theory calculations suggested that the nucleophilic attack of hydroxide on MnV(O) and also WNA to 1e--oxidized MnV(O) are feasibly involved in the catalytic cycles but that direct WNA to MnV(O) is not likely to be the main O-O bond formation pathway in the electrocatalytic water oxidation by 1.

GOAL: The purpose of this study was to evaluate the effectiveness of vitamin C solution (VCS) in reducing adverse reactions caused by painless Lugol chromoendoscopy. BACKGROUND: Lugol chromoendoscopy is an effective method for screening superficial esophageal squamous cell carcinoma, although Lugol iodine solution (LIS) causes mucosal irritation. STUDY: In 4 hospitals in China, patients were randomized and divided into a distilled water (DW) group, an sodium thiosulfate solution (STS) group and a VCS group. Patients' esophageal mucosal surfaces were stained with either 1.2% or 0.5% LIS and then sprayed with DW, STS, or VCS at various concentrations. For the current randomized study, 1610 patients were enrolled in the 1.2% LIS group and 1355 patients were enrolled in the 0.5% LIS group. In addition, 150 patients were enrolled to assess the discoloration effect. The primary outcome for evaluation was the incidence of acute or late adverse reactions after Lugol iodine staining. The secondary outcome for evaluation was the discoloration effect on esophageal iodine-stained mucosa. RESULTS: VCS significantly reduced the occurrence of acute adverse reactions due to staining from 1.2% LIS. The effect of VCS was similar to that of STS but better than that of DW (P

This work describes an effective Cp*RhIII-catalyzed C-H carbenoid functionalization of N-sulfonylarylamides. Compared to the previous late-stage C-H modification methods of N-sulfonylarylamide analogues, this method efficiently achieves the gram-scale transformation with 2.5 mol % Rh-catalyst loading at 0 °C or with a 0.1 mol % Rh-catalyst loading at room temperature. The reaction medium has a great influence on the reaction rate. Methanol is optimal, and adding a nonpolar solvent (such as toluene or 1,2-dichloroethane) causes the rate to decrease. Experiments and density functional theory calculations were performed to rationalize the mechanism of rate control by a polar medium.

Reported herein is the rhodium-catalyzed enantioselective three-component coupling of arene, diene, and dioxazolone that occurs via C–H activation en route to allyl intermediate. This carboaminatio...

Transition-metal based M-N4/C catalysts are appealing for electrocatalytic oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Employing model catalysts, which have well-defined molecular structures and coordination environments, to investigate electrocatalytic performance of M-N4/C sites for ORR and OER is of fundamental significance. Herein, we reported the use of Co tetra(phenyl)porphyrin 1 and Co tetra(pentafluorophenyl)porphyrin 2 as models to probe the role of Co-N4/C sites for oxygen electrocatalysis. We showed that Co porphyrin 1 is more efficient than its structural analogue 2 for oxygen electrocatalysis in alkaline aqueous solutions, indicating that the electron-rich Co-N4/C site is more favored when noncovalently adsorbed on carbon supports. This work inspires rational design of reaction-oriented catalysts for sustainable energy storage and conversion technologies.

Background: Wound complications are a major source of morbidity after cesarean section (CS) and contribute to increased risks in subsequent pregnancies. In the present study, we aim to investigate the wound healing potential of a kind of oligopeptide compound, mainly derived from the marine fish peptides (MFPs), in rats after CS by biomechanical, biochemical, and histological methods. Methods: Eighty-four pregnant Sprague–Dawleyrats were randomly assigned to four groups, namely the control group and 1.1, 2.2, and 4.4 mg/kg MFP groups, respectively. The MFPs or normal saline of the equal volume was intragastrically administered every morning on the second day after CS. On days 5, 10, and 15 after the surgery, seven rats from each group were randomly selected. The samples of skin wound and uterus were harvested and then used for the following experiments and analyses. Results: Using the CS rat model, this study demonstrated that in the MFP groups, the skin tensile strength, uterine bursting pressure, and hydroxyproline (Hyp) were significantly higher than those in the control group at all three time points (P < 0.05). The formation of collagen and smooth muscle fibers and the expression of CD34 and connective tissue growth factor at the incision site were increasingly observed in the MFP groups (P < 0.05). Conclusions: MFPs have a great potential to accelerate the process and quality of wound healing in rats after CS.

The development of efficient heterogeneous catalysts for alkyne hydrogenation with high activity and selectivity is highly desirable and yet remains a great challenge. Herein, a Pd single-atom catalyst (Pds–GDY) is prepared using graphdiyne as support, and used in the semihydrogenation of alkynes. As a proof of concept, the Pds–GDY exhibits a high activity for the semihydrogenation of phenylacetylene under mild reaction conditions, with a TOF of 6290 h−1, and a selectivity of 99.3% at 100% conversion, both much higher than those of the counterparts comprising Pd nanoparticles (NPs), namely, PdNP1–GDY (with 2 nm Pd NPs) and PdNP2–GDY (with 12 nm Pd NPs). In addition, after the full conversion of phenylacetylene, Pds–GDY could still maintain a selectivity as high as 98.9% towards styrene, with almost no phenylethane produced even with a prolonged reaction time; in contrast, for PdNP1–GDY and PdNP2–GDY, within the same reaction time, the selectivity decreases dramatically to 66.6% and 8.5%, respectively. Infrared spectroscopy reveals that Pds–GDY features the weakest adsorption to styrene, which is responsible for its high performance. This work provides an effective strategy to rationally design Pd catalysts for semihydrogenation of alkynes to alkenes with desirable activity and selectivity.

Black silicon fabricated by ultrafast laser is a promising material for infrared detection. However, the structure–property relationship in laser-fabricated amorphous Si is still unclear. By first-principles calculations, different distorted local structures are revealed depending on cooling rate. By comparing the evolutions of structure and property, the bond angle distribution is identified as a good structural descriptor for sub-band absorptions. Glass formation is not simply a freezing of liquid but involves certain structural transitions that happened between 1350 and 850 K. A glass-forming temperature of 1100 K is further revealed which agrees with experiments. The main thermal-management effect is the duration time of glass-forming process. A shorter-pulse laser leads to more distorted structures and thus more defect states and infrared absorptions.

Lignin, a characteristic component of terrestrial plants. Rivers transport large amounts of vascular plant organic matter into the oceans where lignin can degrade over time; however, microorganisms involved in this degradation have not been identified. In this study, several bacterial strains were isolated from marine samples using the lignin-derived compound vanillic acid (4-hydroxy-3-methoxybenzoic acid) as the sole carbon and energy source. The optimum growth temperature for all isolates ranged from 30 to 35°C. All isolates grew well in a wide NaCl concentration range of 0 to over 50 g/L, with an optimum concentration of 22.8 g/L, which is the same as natural seawater. Phylogenetic analysis indicates that these strains are the members of Halomonas, Arthrobacter, Pseudoalteromonas, Marinomonas, and Thalassospira. These isolates are also able to use other lignin-derived compounds, such as 4-hydroxybenzoic acid, ferulic acid, syringic acid, and benzoic acid. Vanillic acid was detected in all culture media when isolates were grown on ferulic acid as the sole carbon source; however, no 4-hydroxy-3-methoxystyrene was detected, indicating that ferulic acid metabolism by these strains occurs via the elimination of two side chain carbons. Furthermore, the isolates exhibit 3,4-dioxygenase or 4,5-dioxygenase activity for protocatechuic acid ring-cleavage, which is consistent with the genetic sequences of related genera. This study was conducted to isolate and characterize marine bacteria of degrading lignin-derived compounds, thereby revealing the degradation of aromatic compounds in the marine environment and opening up new avenues for the development and utilization of marine biological resources.

Although cuprous phosphide (Cu3P) has been widely studied and applied in other fields, its photoluminescence (PL) properties are rarely investigated. Herein, we report that Cu3P can emit near-infrared light at 750 nm. We show that the annealing and the presence of cuprous oxide can enhance the PL emission. The mechanism of the PL enhancement is the improvement of crystal quality and the formation of a space charge region. Our results provide a reference for improving the PL properties of p-type semiconductors.

The chiral-recognition processes of homoproline (hpro) and [Ir(pq)2(MeCN)2](PF6) (pq is 2-phenylquinoline; MeCN is acetonitrile) are investigated, in favor of formation of the thermodynamically stable diastereomers Λ-[Ir(pq)2(d-hpro)] and Δ-[Ir(pq)2(l-hpro)]. Moreover, the diastereoselective photoreactions of Δ-[Ir(pq)2(d-hpro)] and Δ-[Ir(pq)2(l-hpro)] are reported in the presence of O2 at room temperature. Diastereomer Δ-[Ir(pq)2(l-hpro)] is dehydrogenatively oxidized into imino acid complex Δ-[Ir(pq)2(hpro-2H2)] (hpro-2H2 is 3,4,5,6-tetrahydropicalinate), while diastereomer Δ-[Ir(pq)2(d-hpro)] occurs by interligand C-N cross-coupling and dehydrogenative oxidation reactions, affording three products: Δ-[Ir(pq)(d-pqh)] [pqh is N-(2-phenylquinolin-8-yl)homoproline], Δ-[Ir(pq)2(hpro-2H2)], and Δ-[Ir(pq)2(d-hpro-2H6)] [hpro-2H6 is 2,3,4,5-tetrahydropicalinate]. The C-N cross-coupling and dehydrogenative oxidation reactions are competitive, and the dehydrogenative oxidation reactions are regioselective. By optimization of the photoreaction parameters such as the diastereomeric substrate, solvent, and temperature as well as base, each possible competitive product is selectively controlled. In addition, density functional theory calculations are performed to elucidate the distinctly chiral recognition between proline and hpro with an iridium(III) complex.

Quercetin, a natural flavonol existing in many food resources, has been reported to be an effective antimicrobial and anti-inflammatory agent for restricting the inflammation in periodontitis. In this study, we aimed to investigate the anti-inflammatory effects of quercetin on Porphyromonas gingivalis (P. gingivalis) lipopolysaccharide- (LPS-) stimulated human gingival fibroblasts (HGFs). HGFs were pretreated with quercetin prior to LPS stimulation. Cell viability was evaluated by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. The levels of inflammatory cytokines, including interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α), along with chemokine interleukin-8 (IL-8), were determined by enzyme-linked immunosorbent assay (ELISA). The mRNA levels of IL-1β, IL-6, IL-8, TNF-α, IκBα, p65 subunit of nuclear factor-kappa B (NF-κB), peroxisome proliferator-activated receptor-γ (PPAR-γ), liver X receptor α (LXRα), and Toll-like receptor 4 (TLR4) were measured by real-time quantitative PCR (RT-qPCR). The protein levels of IκBα, p-IκBα, p65, p-p65, PPAR-γ, LXRα, and TLR4 were characterized by Western blotting. Our results demonstrated that quercetin inhibited the LPS-induced production of IL-1β, IL-6, IL-8, and TNF-α in a dose-dependent manner. It also suppressed LPS-induced NF-κB activation mediated by TLR4. Moreover, the anti-inflammatory effects of quercetin were reversed by the PPAR-γ antagonist of GW9662. In conclusion, these results suggested that quercetin attenuated the production of IL-1β, IL-6, IL-8, and TNF-α in P. gingivalis LPS-treated HGFs by activating PPAR-γ which subsequently suppressed the activation of NF-κB.

A direct oxidative esterification of alpha-amino carbonyl compounds by two kinds of hydroperoxides, for the synthesis of alpha-keto esters has been developed. The reaction shows broad substrates scope and good functional group tolerance, even for the synthesis of bulkyl esters, and is free of metal catalysts and external additives. Notably, the inhibitor of protein tyrosine phosphatases (PTPases) could be successfully synthesized with our protocol.

A theoretical approach was used to investigate the hydrolytic cleavage mechanisms of the bis(p-nitrophenyl) phosphate (BNPP−) catalyzed by Zn(II)-complexes featuring uncoordinated nucleophiles. Ligand-based and alternative solvent-based nucleophilic attack reaction models are proposed. The pKa values of the Zn(II)-bound water molecules or ligands in the [Zn(LnH)(η-H2O)(H2O)]2+ (n = 1, 2 and 3) complexes, as well as the dimerization tendency of the mononuclear Zn(II)-complexes, were found to significantly influence the reaction mechanisms. The Zn(II)-L3 complexes were found to be more favorable for the hydrolytic cleavage of the BNPP− via a ligand-based nucleophilic attack pathway. This was due to the lower pKa value for the deprotonation of the oxime ligand, the hard dimerization of the mononuclear Zn(II)-L3 species, and the presence of an uncoordinated nucleophile. The origins of the uncoordinated reactions were systematically elucidated. The theoretical results reported here are in good agreement with experimental observations and more importantly, help to elucidate the factors that influence intermolecular nucleophilic attack reactions with coordinated/uncoordinated nucleophiles.

Photocatalytic reductive coupling of carbon-carbon bond to assemble complex molecular frameworks holds the great promising for solar energy storage and value-added chemicals production. This process generally demands noble-photosensitizer or powered by ultraviolet light, along with harsh conditions, which inevitably induces undesired by-product with poor selectivity. Here, we demonstrated selectively reductive aromatic ketones into pinacol on low-cost photocatalysts Ni-doped quantum dots, in which the yield can reach up to 88% with ketones conversion more than 95% under visible-light irradiation for 5 h. A novel mechanism dedicated to the interaction between in situ generated oxidized sacrificial agents TEA•+ and reactants for key ketyl radical formation via proton-coupled electron transfer (PCET) is elaborately probed by EPR measurement, iotope labeling experiments and DFT calculation. This work emerges a new family of catalysts for C-C coupling by solar energy. More importantly, it provides more credible demonstration for TEA activated photocatalytic conversion in organic synthesis.

The inhibitive effects of chitosan on black rot disease caused by Ceratocystis fimbriata in sweet potato tuber root (TR) were evaluated. The results demonstrated that chitosan effectively inhibited the mycelial growth and spore germination of C. fimbriata and directly led to the cell necrosis. Chitosan altered the chitin deposition and influenced the fatty acid composition of C. fimbriata. The application of chitosan effectively controlled the C. fimbriata development in sweet potato TRs 17 days of storage 25 °C. Phenylalanine ammonia lyase (PAL) and superoxide dismutase (SOD) activity were clearly enhanced by the chitosan treatment, while the malondialdehyde (MDA) production was not increased. These findings suggest that chitosan effectively controlled the infection of C. fimbriata in sweet potato TRs owing to its antifungal and eliciting properties, which induced some defense responses during storage.

A visible-light-response, efficient and robust photo-catalyst for CO2 reduction is highly desirable. Herein, we demonstrate that single titanium-oxide species implanted in two-dimensional (2D) graphitic carbon nitride (g-C3N4) matrix (2D TiO-CN) can efficiently photo-catalyze the reduction of CO2 to CO under the irradiation of visible light. The synergistic interaction between single titanium oxide species and g-C3N4 in 2D TiO-CN not only enhances the separation of photo-excited charges, but also results in visible light response of single titanium-oxide species, realizing high activity of CO2 photo-reduction with extremely high CO generation rate of 283.9 μmol·h−1·g−1, 5.7, 6.8 and 292.2 times larger than those of TiO2/CN hybrid material, CN and commercial TiO2, respectively. Time-resolved fluorescence and electron spin resonance spectroscopy revealed the catalytic mechanism of the fabricated 2D TiO-CN photocatalysts for CO2 reduction.

Highly uniform and tight adhering of Fe3O4 particles on carbon fiber film (Fe3O4/CFF) is achieved through a simple in-situ thermal oxidation method. Particularly, 3D CFF with interconnected structure can shorten transfer path and buffer the volume expansion during charge-discharge cycling. Herein, the obtained Fe3O4/CFF anode exhibits a stable cycling performance and excellent high rate capability. The cell delivers a reversible capacity of 1 711 mAh·g–1 at a current density of 100 mA·g–1 after 100 cycles. Even at a high rate density of 2 A·g–1, the specific capacity also can maintain 1 034 mAh·g–1 after 100 cycles. The simplified fabrication is featured with low-cost and this binder-free perspective holds great potential in mass-production of high-performance metal oxide electrochemical devices.

Nature uses Fe porphyrin sites for the oxygen reduction reaction (ORR). Synthetic Fe porphyrins have been extensively studied as ORR catalysts, but activity improvement is required. On the other hand, Fe porphyrins have been rarely shown to be efficient for the oxygen evolution reaction (OER). We herein report an enzyme-inspired Fe porphyrin 1 as an efficient catalyst for both ORR and OER. Complex 1, which bears a tethered imidazole for Fe binding, beats imidazole-free analogue 2, with an anodic shift of ORR half-wave potential by 160 mV and a decrease of OER overpotential by 150 mV to get the benchmark current density at 10 mA cm−2. Theoretical studies suggested that hydroxide attack to a formal FeV=O form the O−O bond. The axial imidazole can prevent the formation of trans HO-FeV=O, which is less effective to form O−O bond with hydroxide. As a practical demonstration, we assembled rechargeable Zn-air battery with 1, which shows equal performance to that with Pt/Ir-based materials.

[This corrects the article DOI: 10.1371/journal.pone.0240187.].

Polyphenols are allelochemicals secreted by aquatic plants that effectively control cyanobacteria blooms. In this study, sensitive response parameters (including CFPs) of Microcystis aeruginosa were explored under the stress of different polyphenols individually and their combination. The combined effects on M. aeruginosa were investigated based on the most sensitive parameter and cell densities. For pyrogallic acid (PA) and gallic acid (GA), the sensitivity order of parameters based on the EC50 values (from 0.73 to 3.40 mg L–1 for PA and from 1.05 to 2.68 mg L–1 for GA) and the results of the hierarchical cluster analysis showed that non-photochemical quenching parameters [NPQ, qN, qN(rel) and qCN] > photochemical quenching parameters [YII, qP, qP(rel) and qL] or others [Fv/Fm, F’v/F’m, qTQ and UQF(rel)] > cell densities. CFPs were not sensitive to ellagic acid (EA) and (+)-catechin (CA). The sensitivity order of parameters for M. aeruginosa with PA-GA mixture was similar to that under PA and GA stress. The quantitative (Toxicity Index, TI) and qualitative (Isobologram representation) methods were employed to evaluate the combined effects of PA, GA, and CA on M. aeruginosa based on cell densities and NPQ. TI values based on the EC50 cells suggested the additive effects of binary and multiple polyphenols, but synergistic and additive effects according to the EC50 NPQ (varied from 0.16 to 1.94). In terms of NPQ of M. aeruginosa, the binary polyphenols exhibited synergistic effects when the proportion of high toxic polyphenols PA or GA was lower than 40%, and the three polyphenols showed a synergistic effect only at the ratio of 1:1:1. Similar results were also found by isobologram representation. The results showed that increasing the ratio of high toxic polyphenols would not enhance the allelopathic effects, and the property, proportion and concentrations of polyphenols played an important role in the combined effects. Compared with cell densities, NPQ was a more suitable parameter as evaluating indicators in the combined effects of polyphenols on M. aeruginosa. These results could provide a method to screen the allelochemicals of polyphenols inhibiting cyanobacteria and improve the inhibitory effects by different polyphenols combined modes.

Vascular endothelial growth factor-2 (VEGFR-2) plays a pivotal role in tumor angiogenesis. Herein, a library of novel 2-(4-(1H-indazol-6-yl)-1H-pyrazol -1-yl)acetamide derivatives were designed and synthesized as VEGFR-2 inhibitors based on scaffold hopping strategy. These compounds exhibited the excellent inhibitory in both VEGFR-2 and tumor cells proliferation. Especially, compound W13 possessed potent VEGFR-2 inhibition with IC50 = 1.6 nM and anti-proliferation against HGC-27 tumor cells with IC50 = 0.36 ± 0.11 μM, as well as less toxicity against normal GES-1 cells with IC50 = 187.46 ± 10.13 μM. Moreover, W13 obviously inhibited colony formation, migration and invasion of HGC-27 cells by adjusting the expression of MMP-9 and E-cadherin, and induced HGC-27 cells apoptosis by increasing ROS production and regulating the expression of apoptotic proteins. Furthermore, W13 blocked the PI3K-Akt-mTOR signaling pathway in HGC-27 cells. In addition, anti-angiogenesis of W13 was proved by inhibiting tube formation and the expression of p-VEGFR-2 in HUVEC cells. All the results demonstrated that W13 could be developing as a promising anticancer agent for gastric cancer therapy.

Pectin oligosaccharides with a molecular weight greater than 700 Da was obtained from the pomace of kiwi (Actinidia arguta). Based on characteristics analysis and inhibitory activity of advanced glycation end products (AGEs) formation in vitro, the target pectin oligosaccharides was added to infant formulas and then subjected to accelerated storage. Results showed that pectin oligosaccharides supplementation inhibited the browning of infant formulas and glassy transition of lactose, and slowed down the increase of water activity under accelerated storage conditions. Pectin oligosaccharides also inhibited the formation of AGEs in infant formulas, such as 5-(hydroxymethyl)furfural, Ne-carboxymethyl-lysine, Ne-carboxyethyl-lysine, methylglyoxal hydromidazolones, glyoxal hydromidazolones, glyoxal-lysine dimer, methylglyoxal-lysine dimer and pyrraline. Besides, permeability studies using Caco-2 cell monolayer also showed that pectin oligosaccharides supplementation inhibited the intestinal absorption of AGEs, especially 5-(hydroxymethyl)furfural, Ne-carboxymethyl-lysine, Ne-carboxyethyl-lysine and glyoxal hydromidazolones. These results provide a reliable theoretical basis for the application of pectin oligosaccharides in infant formulas.

Bile acids in host intestine activate larvae of tapeworms and facilitate its invasion. However, the mechanism underlying this process is poorly understood. In order to better understand responses of tapeworms to host biles, we used RNA-Seq profiling method to study the transcriptomes of Cysticercus Pisiformis (larvae of Taenia Pisiformis) after host bile acid treatment. A total of 338.32 million high-quality clean reads were obtained by Illumina Hiseq platform. Totally, 62,009 unigenes were assembled, 38,382 of which were successfully annotated to known databases. A total of 9324 unigenes were identified as differentially expressed genes (DEGs), of which 5380 and 3944 genes were up- and down-regulated in the group treated with bile acids, respectively. Gene Ontology analysis revealed that biosynthesis and energy metabolism potential were significantly strengthened after host bile treatment in C. pisiformis. Similarly, KEGG pathway analysis revealed an enrichment of pathways related to lipid metabolism and carbohydrate metabolism. Among them, 'AMPK signaling pathway' which is critical in balancing cellular energy, was significantly enriched after bile acids activation. In addition, pathways of 'Fatty acid biosynthesis', 'Fatty acid elongation', 'Starch and sucrose metabolism', and 'glycolysis gluconeogenesis' were also significantly changed after bile acid treatment. qRT-PCR analysis confirmed the differential abundances of some key genes in these pathways. Our data suggest that host bile acids remarkably promote the pathways of energy metabolism of this parasite and regulate the genes involved in balancing lipid metabolism and carbohydrate metabolism. These findings provide new insights on the lifecycle of Taenia parasites.

The intracellular fatty acid-binding proteins (FABPs) are a well-conserved family that function as lipid chaperones. Ongoing studies are focused on identification of the mechanistic complexity and vast biological diversity of different isoforms of FABPs. However, the molecular mechanism of FABP5 in the regulation of milk fat synthesis in the mammary gland of dairy cows is still largely unknown. Here, we report that FABP5 acts as a critical regulator of terol response element-binding protein-1c (SREBP-1c) gene expression induced by methionine (Met) and estrogen (E2) in bovine mammary epithelial cells (BMECs). We observed that the expression of FABP5 was markedly higher in dairy cow mammary tissue during the lactating period than the puberty period and the dry period. FABP5 is located in the cytoplasm, and Met and E2 significantly increase the protein levels of FABP5 in BMECs. Using gene function study approaches, we revealed that FABP5 positively regulates SREBP-1c gene expression and promotes milk fat synthesis. We confirmed that FABP5 is required for Met- and E2-induced SREBP-1c gene expression and milk fat synthesis. We further uncovered that fatty acids are needed for FABP5-mediated SREBP-1c gene expression. Thus, our study demonstrates that FABP5 is a critical regulator of Met- and E2-induced SREBP-1c gene expression leading to milk fat synthesis.

In this study, the fungicidal effects and detailed action of chitosan against Ceratocystis fimbriata were evaluated. The results demonstrated that chitosan exhibited strong antifungal activity that restricted the mycelium extension and changed the hyphal morphology. Fluorescein diacetate (FDA) and propidium iodide (PI) double-staining directly visualized decreased cell viability in response to chitosan treatment. Investigation of the PI influx showed that chitosan induced irreversible cell membrane damage. The efflux of potassium ions from the cytosol into the extracellular matrix demonstrated that chitosan induced the leakage of intracellular components. Massive intracellular bis-(1, 3-dibutylbarbituric acid) trimethine oxonol [DiBAC4(3)] accumulation indicated the dissipation of membrane potential. Furthermore, chitosan clearly decreased the activity of H+/K+ ATPase. Fluorescence microscopy revealed that the fluorescence distribution and intensity of fluorescein isothiocyanate (FITC) changed as the incubation time increased. These results indicate that chitosan exerts a fungicidal effect via its ability to disturb fungal membranes.

Pyroptosis is a form of cell death that is uniquely dependent on caspase-1. Pyroptosis involved in oxidized low-density lipoprotein (ox-LDL)-induced human macrophage death through the promotion of caspase-1 activation is important for the formation of unstable plaques in atherosclerosis. The mitochondrial outer membrane protein NIX directly interacts with microtubule-associated protein 1 light chain 3 (LC3). Although we previously showed that NIX-mediated mitochondrial autophagy is involved in the clearance of damaged mitochondria, how NIX contributes to ox-LDL-induced macrophage pyroptosis remains unknown. Here, immunoperoxidase staining Nix expression decreased in human atherosclerosis. When we silenced NIX expression in murine macrophage cell, active caspase-1, and mature interleukin-1β expression levels were increased and LC3 was reduced. In addition, LDH release and acridine orange and ethidium bromide staining indicated that damage to macrophage cell membranes induced by ox-LDL was substantially worse. Moreover, intracellular reactive oxygen species and NLRP3 inflammasome levels increased. Taken together, these results demonstrated that NIX inhibits ox-LDL-induced macrophage pyroptosis via autophagy in atherosclerosis.

The contamination of food with Aspergillus flavus and subsequent aflatoxins is one of the most serious safety problems in the world. In this study of nerol (NEL)’s antifungal mechanism of action, we observed morphological and physiological changes in Aspergillus flavus. We found that NEL resulted in elevated levels of reactive oxygen species (ROS) and calcium ions (Ca2+). On ROS assays, compared with the controls, the proportion of fluorescent cells treated with concentrations of 0.25, 0.5, 1, and 2 μL/mL NEL increased to 8.4 ± 1.07%, 10.2 ± 1.72%, 13.4 ± 0.50%, and 26.2 ± 4.21%, respectively. Increased mitochondrial dysfunction and oxidative stress induced by the interactions between Ca2+ and ROS subsequently activate the release of cytochrome c and caspase activity. Characteristic changes of apoptosis were also observed via various detection methods, including phosphatidylserine externalization, nuclear condensation, and DNA fragmentation. Meanwhile, we found that the expression of CaMKs increased significantly in NEL-treated cells. In conclusion, our findings indicate that NEL has great potential as an eco-friendly antifungal agent for food preservation.

Micro-ripple and micro-bead structures are formed on a silicon (Si) surface after irradiation with femtosecond laser pulses in nitrogen (N2) atmosphere. Simultaneously, supersaturated nitrogen (N) atoms, with a concentration above 1020 cm−3, are doped into the textured black Si layer via laser ablation. The N-doped Si exhibits strong below-bandgap infrared absorption from 1.1 to $2.5~\mu \text{m}$ , which remains nearly unchanged after annealing for 30 min at 873 K. The mechanism of this thermally stable infrared absorption is analyzed by first-principles calculations. According to the transmission electron microscopy results, multiple phases (including single crystalline, nanocrystalline, and amorphous phases) are observed in the laser-irradiated layer. Hall Effect measurements prove that N-dopants induce a low background free-carrier concentration ( $\sim 1.67\times 10^{16}\,\,\text {cm}^{-3}$ ). Finally, a Schottky-based bulk structure photodiode is made. This broadband photodiode exhibits good thermal stability and a photo-responsivity of 5.3 mA/W for $1.31~\mu \text{m}$ at a reverse bias of 10 V.

A novel ratiometric fluorescence sensing system for the ultrasensitive detection of Hg2+ was developed. It used aminofunctionalized silicon nanoparticles and rhodamine B, which exhibit two distinct...

A new and practical approach to α-dithioacetal/α-diselenoacetal amides has been developed, combining sequential functionalization of amides and a C–C bond cleavage strategy. In this reaction, various α-dithioacetal/α-diselenoacetal amides from 3-oxo-butanamides were prepared in one step with good regioselectivity and functional group tolerance.

Phase-change memory (PCM) material is the promising material system for nonvolatile-memory technology. Performance optimization of PCM device urgently requires the deeper clarification of its material “Gene”. In this study, through first-principles calculations, p-orbital-aligned atom chains are identified to play important roles in governing optoelectronic reflectivity in amorphous Ge2Sb2Te5. These atom chains make the electronic state of the amorphous Ge2Sb2Te5 hold strong electron-polarized components, thereby governing the optical property. The present study offers a new understanding of “Gene” for PCM materials which benefit the material design and the performance improvement of PCM devices.

An efficient, environmentally benign and unprecedented synthesis of various α-sulfenylated amides/esters has been developed under oxygen atmosphere. The reaction shows good functional group tolerance and excellent chemo/regioselectivity. All the desired products were obtained in moderate to excellent yields, even on the gram scale. Practically, the related α-thiol Weinreb amide can be readily transferred to a series of prospective compounds, and selenium atom can be introduced to the α-sites of the amides in high yields.

Total synthesis of the originally proposed chrysamide B (2) is described, which features a convergent assembly of the chiral piperazine core and epoxy-acid. Mismatched spectroscopic data for the synthetic sample compared to that for the isolate led us to propose the revised structure 3 based on biosynthetic considerations. In a further antibacterial assay, chrysamide B and its diastereomer 2 exhibited different activities.

A series of novel and facile quaternary composite BiVO 4 /MWCNT/Ag@AgCl were synthesized through hydrothermal and in situ oxidization method. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TG), Brunauer Emmett Teller surface area (BET), and Raman scattering spectroscopy were utilized to characterize the as-mentioned quaternary composite. The catalytic performance of the composite was investigated by the degradation of 5 mgL −1 rhodamine B (RhB) under visible light irradiation (λ ≥ 420 nm). The weight ratio of Ag and the mole ratios of Ag to AgCl in the composite can influence the photocatalytic performance. When the weight ratio of Ag is 20% and the mole ratio of AgNO 3 to FeCl 3 is 4: 1, the catalyst exhibits much superior visible light catalytic activity than pure BiVO 4 and it can decompose 99% of RhB in 100 min.

A simple and practical NaI-catalyzed direct C-H sulfenylation of arenes has been developed under air. In this reaction, aryl sulfides were obtained in moderate to excellent yields with high regioselectivity from readily available aromatic compounds and aryl/alkyl thiols, even on gram scale. To demonstrate the practicability of this reaction, two bioactive compound skeletons were synthesized in good yields. This method can also be used to late-stage modification of curcumin.

Bacterial spoilage is an important reason causing freshness deterioration of fish during postmortem storage. The aim of this study is mainly to investigate the role of bacteria in freshness and the degradation of inosine 5′-monophosphate (IMP) as well as nucleotide derived values in chilled sturgeon (hybrid, Acipenser schrenckiid × Huso dauricus) fillets using a microbial reduction pretreatment. During storage at 4 or -1 °C, lower total bacterial count and total volatile base nitrogen in the treated samples was observed when compared to the control samples. But very close K, Ki value and IMP was observed in both groups, although higher IMP was recorded at day 6 and 9 at 4 °C. In later storage period, accelerated decrease of inosine (Ino) and increment of hypoxanthine (Hx) occurred in two control groups, resulting in a rapid increase of G and H values, significant higher than the treated groups. Six predominant spoilage bacteria (Acinetobacter johnsonii, Acinetobacter lwoffii, Shewanella baltica, Pseudomonas Fragi, Pseudomonas koreensis and Pseudomonas antarctica) were isolated from the sturgeon fillets during storage. Based on the results of respective co-cultivation of IMP with the six species, only Acinetobacter johnsonii had ability to degrade IMP when reached a high density of 2.84 × 109 CFU/mL. Results suggested that microbial reduction pretreatment could better the freshness of chilled sturgeon fillet. Comparing to endogenous IMPase, spoilage bacteria probably played a small role in IMP degradation, but affected considerably the decomposition of Ino to Hx.

The essential oil extracted from the black Piper nigrum L. (BPEO) was analyzed for antioxidant, hepatoprotective and antifungal activities. BPEO is rich in total phenolics, total flavonoids and proanthocyanidins, and showed good free radicals and lipid peroxidation scavenging capacities. In a CCl4-induced liver injury mice model, the BPEO treated groups showed increases in the catalase (CAT), glutathione (GSH) and total superoxide dismutase (T-SOD) activities present in the liver and kidney, and reverses the CCl4-elevated total bilirubin (TBIL), glutamate pyruvate transaminase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP) and malondialdehyde (MDA) level, which were confirmed in further analyses of kidney tissue sections. BPEO can effectively inhibit the growth of Aspergillus flavus spoilage fungus in maize. Further analyses indicated that BPEO disrupt the permeability barrier of the cell membrane and lead to mitochondrial dysfunction in A. flavus. Therefore, the current study proved BPEO's potential as hepatoprotective products and natural food preservatives.

The composite of fluorine-doped SnO2 anchored on reduced graphene oxide (F-SnO2/rGO) has been synthesized through a hydrothermal method. F-SnO2 particles with average size of 8 nm were uniformly anchored on the surfaces of rGO sheets and the resulting composite had a high loading of F-SnO2 (ca. 90%). Benefiting from the remarkably improved electrical conductivity and Li-ion diffusion in the electrode by F doping and rGO incorporation, the composite material exhibited high reversible capacity, excellent long-term cycling stability and superior rate capability. The electrode delivered a large reversible capacity of 1037 mAh g−1 after 150 cycles at 100 mA g−1 and high rate capacities of 860 and 770 mAh g−1 at 1 and 2 A g−1, respectively. Moreover, the electrode could maintain a high reversible capacities of 733 mAh g−1 even after 250 cycles at 500 mA g−1. The outstanding electrochemical performance of the as-synthesized composite make it a promising anode material for high-energy lithium ion batteries.

GeSbTe alloys have the ability of rapidly transforming between amorphous and crystalline phases. Therefore, they can be used in the non-volatile phase change memory. Recently, a vacancy-ordered cubic Ge 2 Sb 2 Te 5 ( VOC GST) phase change material where the vacancies are highly ordered in the (111) plane, has been experimentally demonstrated by STEM. However, studies are mainly on the structural characterization, rather than on the phase change behavior and possible applications of the VOC GST. Here, using first-principles molecular dynamic simulations, we study the melt-quenched amorphization process and its possible applications. We find that the VOC GST exhibits a quasi-two-dimensional amorphization process that is triggered by the diffusion of Ge atoms but not others. A partial amorphous ( P-amor ) phase is obtained, which can act as an intermediate state between the pure amorphous and pure crystalline phases for possible ternary-state data storage.

Two pairs of chlorine-containing phenylpropanoid enantiomers ( 1a/1b and 2a/2b ) were isolated from the rhizomes of Acorus tatarinowii . Interestingly, these optical isomers ( 1a/1b and 2a/2b ) were co-existed in the same plant, which were characterized as the first halogen-containing natural products from the genus Acorus . Their structures and absolute configurations were elucidated by a combination of spectroscopic analysis and a single-crystal X-ray diffraction, assisted by a modified Mosher’s method. The phenylpropanoid isomers ( 1a/1b and 2a/2b ) were evaluated for their antioxidant activities using DPPH assay and cytotoxic activities against five human cancer cell lines.

A novel actinobacterium, designated KLBMP 5180T, was isolated from the surface-sterilized root of a coastal halophyte, Limonium sinense, collected from the city of Lianyungang, Jiangsu Province, eastern China. The isolate was Gram-stain-positive, aerobic and non-motile. The components of the cell-wall peptidoglycan were lysine, glutamic acid and alanine. The predominant menaquinone was MK-9. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol, one unknown phospholipid, one unidentified glycolipid and two unidentified lipids. anteiso-C15 : 0 and iso-C16 : 0 were the major cellular fatty acids. The DNA G+C content of strain KLBMP 5180T was 60.0 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KLBMP 5180T belongs to the genus Glutamicibacter and was related most closely to Glutamicibacter nicotianae DSM 20123T (99.3 % similarity), Glutamicibacterarilaitensis Re117T (99.3 %) and Glutamicibacter mysorens LMG 16219T (99.1 %); similarity to other type strains of the genus Glutamicibacter was lower than 98.5 %. However, DNA–DNA relatedness values between strain KLBMP 5180T, G . nicotianae DSM 20123T, G. arilaitensis Re117T and G. mysorens LMG 16219T were 47.5±2.6, 51.3±3.1 and 41.2±4.3 %, respectively. The combination of DNA–DNA hybridization, phylogenetic, phenotypic and chemotaxonomic data supported the suggestion that strain KLBMP 5180T represents a novel species of the genus Glutamicibacter, for which the name Glutamicibacter halophytocola sp. nov. is proposed. The type strain is KLBMP 5180T (=DSM 101718T=KCTC 39692T).

The antifungal activity of Nerol (NEL) against Candida albicans, a pathogenic fungus, has a minimum inhibitory concentration (MIC) of 4.4mM that causes noteworthy candidacidal activity through an apoptosis-like mechanism. Calcium (Ca2+) levels and reactive oxygen species (ROS) production, which are the major causes of apoptosis, were determined in C. albicans cells treated with NEL and were found to increase, which related to mitochondrial dysfunction and disruption. A series of characteristic changes of apoptosis caused by NEL, including mitochondrial membrane depolarization, cytochrome c (cyt c) release, and metacaspase activation were examined using a flow cytometer and Western blot. The results showed that an increase in intracellular Ca2+ and ROS led to dramatically decreased mitochondrial membrane potential (MMP); cyt c was also released from the mitochondria to the cytosol. Other early apoptotic features were also observed with the metacaspase activation. Finally, the morphological changes of the cells were observed, including phosphatidylserine (PS) externalization, nuclear condensation, and DNA fragmentation through Annexin V-FITC and PI double staining, TUNEL assay, and DAPI staining. The results supported the hypothesis that NEL was involved in the apoptosis of C. albicans cells not only at the early stages, but also at the late stages. In summary, NEL can trigger mitochondrial dysfunction and disruption via elevation of Ca2+ and ROS leading to apoptosis in C. albicans. This research on the mechanism of cell death triggered by NEL against C. albicans has important significance for providing a novel treatment of C. albicans infections.

This study was undertaken to determine levels of halogenated flame retardants (HFRs) on skin surface to provide preliminary exposure estimates from dermal absorption. Skin wipes of palms, back-of-hands, and forearms were collected from 30 participants by using gauze pads soaked in isopropyl alcohol. Eight polybrominated diphenyl ethers (PBDEs), two novel brominated FRs, and two Dechlorane Plus (DPs) isomers were determined. BDE209, Decabromodiphenylethane (DBDPE), and 1, 2-Bis (2, 4, 6-tribromophenoxy) ethane (BTBPE) were most frequently detected. BDE209 showed the highest median level (1760 ng m−2), followed by DBDPE (277 ng m−2) and anti-DP (64 ng m−2). The comparison of levels on palms and back-of-hands revealed no statistical differences, but both were significantly higher than the levels on forearms. Detections of HFRs on arms suggested that skin areas covered by clothing were exposed to these chemicals likewise. BDE209 and DPs levels from three repeated samples showed moderate to strong reliability over 3 months, while the levels of other compounds were not statistically reliable. Males had significant higher levels than females for most HFRs, while participants' age, time from last hand washing to sampling, and other behaviors contributed limitedly to the variations in levels. Daily uptakes of HFRs through dermal absorption were estimated. The estimated median total exposure from palms, back-of-hands, and forearms were 25.9, 1.6, and 7.2 ng d−1 for ∑PBDEs, ∑DPs, and ∑NBFRs, respectively, which were in the same ranges as those from diet and dust ingestion for adults in China, suggesting that dermal absorption would be an important exposure route for HFRs.

Petroleum residues with varying cutting depth and corresponding vacuum distillates have been prepared from laboratory deep-vacuum fractionation using unconventional heavy oil (UHO) originated from Venezuela first. They are then sequentially characterized by general analysis, process analysis, and pyrolysis analysis with thermogravimetric analysis (TGA), derivative thermogravimetric analysis (DTG), and differential scanning calorimetry (DSC). Results indicate that a greater increase in distillates recovery would be expected in the case of UHO than that of other referenced crudes under the same cut temperature and stand a good chance to make refineries involved with UHO get comfort by partially offsetting the shortage of light distillates. From the view of structural composition characteristics, cuts, even the ones with high cut temperature, have a high chance of cracking into compounds with lower molecular weight during conversion. Notably, in the case of +565 °C petroleum residue (R5), except for the endo...

Notoginseng, the root of Panax notoginseng, has been used to treat wounds and ulcers for several years in China. However, a rare report was found on the antifungal effect of saponin from notoginseng or a heat-transformed one, particularly against dermatophytes. In this study, notoginseng saponin (NS) was heated in a reaction kettle to produce heat-transformed ginsenoside (HTS). Chromatography and spectroscopic characterization revealed that five polar ginsenosides in NS (notoginsenoside-R1, ginsenoside-Rg1, -Re, -Rb2, -Rd) were almost transformed to three less polar ginsenosides in HTS (ginsenoside-Rk3, -Rh4, -Rh5). HTS showed higher inhibitory activity than that of NS against Epidermophyton floccosum, Trichophyton rubrum, and Trichophyton mentagrophytes, with the lower minimum inhibitory concentration (MIC, 16 or 31.25 μg mL−1) and minimum fungicidal concentration (MFC, 125 or 250 μg mL−1). Moreover, less polar ginsenosides-Rk3, -Rh4, and -Rh5 showed the highest inhibitory activity among the ginsenoside monomers with the lowest MIC (16 μg mL−1) and MFC (62.5 μg mL−1). It was also found that the antifungal activity of individual ginsenosides was negatively correlated with the number of their sugar moieties. Moreover, the antifungal activity of HTS might be attributed to the damage of cell membrane and decrease of membrane potential, easily caused by less polar ginsenosides. Thus, the results indicated that HTS could be applied as antifungal agents to treat ringworm.

A highly sensitive and selective fluorescence sensor for detection of chromium(VI) and hydrogen sulfide was developed by using silicon nanoparticles (SiNPs) as probe. The fluorescence of SiNPs was effectively quenched by Cr(VI) via the inner filter effect. Upon addition of hydrogen sulfide, the fluorescence of SiNPs was recovered due to the oxidation-reduction between Cr(VI) and H 2 S. Under optimal conditions, the wide linear response ranges were obtained over the range of 0.1–200 μM and 0.1–200 μM with the low detection limits of 28 nM and 22 nM for Cr(VI) and H 2 S, respectively. The sensing platform was successfully applied to determination of Cr(VI) and H 2 S in real samples.

Methyl-coenzyme M reductase (MCR) is the key enzyme of methanogenesis and anaerobic methane oxidation. The activity of MCR is dependent on the unique nickel-containing tetrapyrrole known as coenzyme F430. We used comparative genomics to identify the coenzyme F430 biosynthesis (cfb) genes and characterized the encoded enzymes from Methanosarcina acetivorans C2A. The pathway involves nickelochelation by a nickel-specific chelatase, followed by amidation to form Ni-sirohydrochlorin a,c-diamide. Next, a primitive homolog of nitrogenase mediates a six-electron reduction and γ-lactamization reaction before a Mur ligase homolog forms the six-membered carbocyclic ring in the final step of the pathway. These data show that coenzyme F430 can be synthesized from sirohydrochlorin using Cfb enzymes produced heterologously in a nonmethanogen host and identify several targets for inhibitors of biological methane formation.