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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.

Ultrafast laser-induced phase/structural transitions show a great potential in optical memory and optical computing technologies, which are believed to have advantages of ultrafast speed, low power consumption, less heat diffusion and remote control as compared with electronic devices. Here, we review and discuss the principles of orbital-selective electronic excitation and its roles in phase/structural transitions of phase-change memory (PCM) materials, including Sc0.2Sb1.8Te3 and GeTe phases. It is demonstrated, that the mechanism can influence the dynamics or results of structural transitions, such as an ultrafast amorphization of Sc0.2Sb1.8Te3 and a non-volatile order-to-order structural transition of GeTe. Without thermal melting, these structural transitions have the advantages of ultrafast speed and low power consumption. It suggests that the orbital-selective electronic excitation can play a significant role in discovering new physics of phase change and shows a potential for new applications.

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.

Developing highly active catalysts for photo/electrocatalytic water splitting is an attractive strategy to produce H2 as a renewable energy source. In this study, a new nickel boron oxide/graphdiyne (NiBi/GDY) hybrid catalyst was prepared by a facile synthetic approach. Benefitting from the strong electron donating ability of graphdiyne, NiBi/GDY showed an optimized electronic structure containing lower valence nickel atoms and demonstrated improved catalytic performance. As expected, NiBi/GDY displayed a high photocatalytic H2 evolution rate of 4.54 mmol g−1 h−1, 2.9 and 4.5 times higher than those of NiBi/graphene and NiBi, respectively. NiBi/GDY also displayed outstanding electrocatalytic H2 evolution activity in 1.0 M KOH solution, with a current density of 400 mA/cm2 at an overpotential of 478.0 mV, which is lower than that of commercial Pt/C (505.3 mV@400 mA/cm2). This work demonstrates that GDY is an ideal support for the development of highly active catalysts for photo/electrocatalytic H2 evolution.

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.

Objective To confirm the role of long noncoding RNA differentiation antagonizing non‐protein coding RNA (DANCR) in chondrocyte inflammatory injury in osteoarthritis (OA) in vitro, as well as its molecular mechanism. Methods Human primary chondrocytes were treated with lipopolysaccharide (LPS) to construct a chondrocyte inflammatory injury in human OA cell model. Gene expression was detected using real‐time quantitative polymerase chain reaction. Cell inflammatory injury was evaluated by Cell Counting Kit‐8 assay, flow cytometry, and enzyme‐linked immunosorbent assay. The interplay between miRNA‐19a‐3p (miR‐19a) and DANCR was validated by dual‐luciferase reporter assay and RNA immunoprecipitation. Results Expression of DANCR was upregulated, and miR‐19a was downregulated in human OA cartilage and LPS‐treated primary chondrocytes in vitro. Moreover, DANCR expression was inversely correlated with miR‐19a in OA patients. LPS reduced cell viability and increased the apoptotic rate and secretion of interleukin (IL)‐1β, IL‐6, IL‐8, as well as tumor necrosis factor (TNF)‐α in primary chondrocyte cells in vitro, suggesting an inflammatory injury model of OA. Functionally, knockdown of DANCR could attenuate LPS‐induced apoptosis and inflammatory response, as evidenced by improved cell viability, and reduced apoptotic rate and products of IL‐1β, IL‐6, IL‐8, and TNF‐α. Notably, DANCR negatively regulated miR‐19a expression, presumably via sponging. Furthermore, miR‐19a deletion eliminated the effect of DANCR knockdown on apoptosis and the inflammatory response of primary chondrocytes under LPS stress. Conclusion Differentiation antagonizing non‐protein coding RNA silencing could protect human chondrocyte cells against LPS‐induced inflammatory injury and apoptosis through targeting miR‐19a, suggesting a vital role of the DANCR/miR‐19a axis in OA., Highlights Expression of DANCR and miR‐19a was upregulated and downregulated in human OA cartilage, respectively.Silencing DANCR alleviated LPS‐induced apoptosis and inflammatory response in primary chondrocytes, which could be counteracted by deleting miR‐19a.DANCR functioned as a sponge for miR‐19a.

Cancer-associated fibroblast (CAF) secretes extracellular vesicle (EV)-encapsulated microRNAs (miRNAs) which have been underlined great promise for therapeutic target for diseases and cancers. Our study aimed to explore the role of EV-encapsulated miR-10a-5p from CAFs in angiogenesis in cervical cancer. Expression of miR-10a-5p in clinical samples of cervical cancer and cancer cells was detected by in situ hybridization and RT-qPCR. Results demonstrated that miR-10a-5p expression was upregulated in both cancer tissues and cells. CAFs and normal fibroblasts (NFs) from cervical cancer patient tissues were characterized under transmission electron microscopy, followed by EV isolation from CAFs. The EVs labeled with PKH67 were cultured with cervical squamous cell carcinoma (CSCC) cell line (SiHa) and HUVECs. Data indicated that CAF-EVs were internalized by cancer cells and promoted cell proliferation and tube formation. CAF-EVs then were transfected with miR-10a-5p inhibitor and then injected into nude mice. While injection of CAF-EVs promoted tumor growth and increased VEGFR and CD31 expression level, miR-10a-5p inhibitor-treated CAF-EVs resulted in decreased tumor volume and amount of vessel around tumor. Of note, dual-luciferase reporter gene assay and bioinformatic analysis indicated TBX5 as a target gene of miR-10a-5p. Moreover, EV-derived miR-10a-5p promoted angiogenesis in vivo and in vitro through activation of Hedgehog signaling via downregulation of TBX5. Taken altogether, miR-10a-5p in CAF-EVs promoted CSCC cell angiogenesis and tumorigenicity via activation of Hh signaling by inhibition of TBX5, providing insight into novel treatment based on miR-10a-5p against CSCC.

Metal allyl species are versatile intermediates in a number of coupling reactions. However, Rh(III) π-allyls have been rarely elaborated in the context of asymmetric C-H functionalization. Reported herein is chiral Rh(III) cyclopentadienyl-catalyzed enantioselective synthesis of lactams and isochromenes via oxidative [4+1] and [5+1] annulation, respectively, between arenes and 1,3-enynes. The reaction proceeds via a C-H activation, alkenyl to allyl rearrangement, and nucleophilic cyclization cascade. The mechanistic details of the [4+1] annulation of N-methoxybenzamide and an 1,3-enyne have been elucidated by a combination of experimental and computational methods. DFT studies indicate that following the C-H activation and alkyne insertion, a Rh(III) alkenyl intermediate undergoes δ-hydrogen elimination of the allylic C-H via a six-membered ring transition state to produce a Rh(III) enallene hydride intermediate. Subsequent hydride insertion and allyl rearrangement affords several rhodium(III) allyl intermediates, and a rare Rh(III) η4 ene-allyl species with π-agostic interaction undergoes SN2'-type external attack by the nitrogen nucleophile, instead of C-N reductive elimination, as the stereodetermining step.

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 effect of super-chilling at -2°C compared with ice storage at 0°C on flavor quality changes of turbot (Psetta maxima) was investigated. Changes in total volatile basic nitrogen (TVB-N), sensory attributes and volatile compounds were periodically examined for 20 days. Results demonstrated that super-chilling retarded the increases of TVB-N values and maintained better sensory quality compared to the ice storage. Additionally, GC-MS analysis showed super-chilling could more effectively maintain the characteristic volatiles responsible for fresh fish flavor and reduce the contents of putrid compounds such as TMA and acetic acid.

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.

Three new macrocyclic trichothecenes possessing rare 6′-ketal moieties, roridoxins A–C (1–3), and five known compounds (4–8) were isolated from the insect-associated fungus Myrothecium roridum. Their structures were confirmed by a combination of NMR and HRESIMS data, while their absolute configurations were unambiguously determined by single-crystal X-ray analysis and electronic circular dichroism experiments. Trichothecenes 1 and 3 showed potent antifungal activities against four strains of phytopathogenic fungi. In addition, 1, 3, 5, and 6 were found to significantly inhibit the cell growth of Candida albicans with minimal inhibitory concentration values from 8.8 to 18.5 μg/mL. Moreover, they were able to inhibit the biofilm formation of C. albicans better than the positive control.

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.

Modulating the distribution of various states in protein ensembles through distal sites may be promising in the evolution of enzymes in desired directions. However, the prediction of distal mutation hotspots that stabilize the favoured states from a computational perspective remains challenging. Here, we presented a strategy based on molecular dynamics (MD) and Markov state models (MSM) to predict distal mutation sites. Extensive MD combined with MSM was applied to determine the principally distributed metastable states interconverting at a slow timescale. Then, molecular docking was used to classify these states into active states and inactive ones. Distal mutation hotspots were targeted based on comparing the conformational features between active and inactive states, where mutations destabilize the inactive states and show little influence on the active state. The proposed strategy was used to explore the highly dynamic MHETase, which shows a potential application in the biodegradation of poly(ethylene terephthalate) (PET). Seven principally populated interrelated metastable states were identified, and the atomistic picture of their conformational changes was unveiled. Several residues at distal positions were found to adopt more H-bond occupancies in inactive states than active states, making them potential mutation hotspots for stabilizing the favoured conformations. In addition, the detailed mechanism revealed the significance of calcium ions at a distance from the catalytic centre in reshaping the free energy landscape. This study deepens the understanding of the conformational dynamics of α/β hydrolases containing a lid domain and advances the study of enzymatic plastic degradation.

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.

Restoration of submerged plants in eutrophic lakes can reduce nutrients and phytoplankton biomass in the water body. However, the effect of submerged plants on phytoplankton communities and their photosynthetic activity in situ are still poorly understood. Here, we studied the response of phytoplankton community structure and fluorescence parameters to different submerged plants coverage, the relationship of phytoplankton community and fluorescence parameters with submerged plants coverage and water physicochemical parameters were analysed in sampling area of Hangzhou West Lakes. The results showed that the coverage and biomass of submerged plants were negatively correlated with nitrogen and phosphorus contents in water body but positively correlated with total phenol content. The ratio of nitrogen to phosphorus in the study site changed greatly (32.25-124.54). In spring and summer, Oscillatoria and Leptolyngbya (Cyanophyta) were the dominant species, while in autumn and winter, the dominant species were Cyclotella (Chlorophyta), and Melosira and Cymbella (Bacillariophyta). Compared with Chlorophyta and Bacillariophyta, fluorescence parameters of Cyanophyta were more sensitive to total phosphorus, N:P ratio, total phenols, pH, and electric conductivity. Fluorescence parameters of Chlorophyta and Bacillariophyta were only affected by underwater light. Total phosphorus (TP) and N:P had a negative effect on the maximum photochemical electron yield of Cyanophyta. Furthermore, Cyanophyta was inhibited by total phenols from submerged plants. When phytoplankton were under stress, photochemical electron yield decreased significantly, whereas non-photochemical quenching increased. The structural equation model showed that the coverage of submerged plants might indirectly affect the fluorescence parameters of Cyanophyta by affecting nitrogen, phosphorus, and total phenol contents in the water body. These findings contribute to the understanding of the mechanisms underlying the impact of submerged plant restoration on phytoplankton community dynamics in subtropical eutrophic shallow lakes and provide a theoretical basis for the management of lakes.

Reported herein is asymmetric [3+2] annulation of arylnitrones with different classes of alkynes catalyzed by chiral rhodium(III) complexes, with the nitrone acting as an electrophilic directing group. Three classes of chiral indenes/indenones have been effectively constructed, depending on the nature of the substrates. The coupling system features mild reaction conditions, excellent enantioselectivity, and high atom-economy. In particular, the coupling of N-benzylnitrones and different classes of sterically hindered alkynes afforded C-C or C-N atropochiral pentatomic biaryls with a C-centered point-chirality in excellent enantio- and diastereoselectivity (45 examples, average 95.6 % ee). These chiral center and axis are disposed in a distal fashion and they are constructed via two distinct migratory insertions that are stereo-determining and are under catalyst control.

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 general one-step synthesis of symmetrical or unsymmetrical 1,4-di(organo)fullerenes from organo(hydro)fullerenes (RC60H) is realized by direct oxidative arylation. The new combination of catalytic trifluoromethanesulfonic acid (TfOH) and stoichiometric o-chloranil is the first to be used to directly generate an R-C60+ intermediate from common RC60H. Unexpectedly, the in situ generated R-C60+ intermediate is shown to be quite stable in whole 13C NMR spectroscopy characterization in the absence of cation quenching reagents. Because the direct oxidation of common RC60H to form the corresponding R-C60+ has never been realized, the present combination of TfOH and o-chloranil solves the challenges associated with the formation of stable RC60+ cations from common RC60H without any coordination of an R group.

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.

The biocontrol activity and chemical composition of the volatile organic compounds (VOCs) produced by Pseudomonas chlororaphis subsp. aureofaciens SPS-41 were investigated. The VOCs inhibited mycelial growth and spore germination in Ceratocystis fimbriata, which causes black rot disease in sweet potato tuber roots (TRs) and showed wide-spectrum antifungal activity against several plant pathogenic fungi. A microscopic examination of C. fimbriata cells suggested morphological changes and a loss of cellular contents. Different inoculation strategies significantly affected the antifungal activity of the VOCs. In the volatile profile of SPS-41, the most abundant compound, 3-methyl-1-butanol, followed by phenylethyl alcohol and 2-methyl-1-butanol showed strong inhibition toward C. fimbriata. The weight loss rate and disease severity of the TRs were significantly reduced in response to the VOCs emitted by SPS-41. The results suggest that the VOCs produced by P. chlororaphis subsp. aureofaciens SPS-41 might constitute an attractive biological fumigant for controlling black rot disease in sweet potato TRs.

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.

A novel tert-butyl hydroperoxide (TBHP) promoted CH2-extrusion reaction of α-amino carbonyl compounds has been developed, which is driven by a demethylenation process to give various ring contraction products γ-lactams under radical conditions. The reaction shows good functional group tolerance and excellent chemo/regioselectivity; all the desired products are obtained in moderate to excellent yields.

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.

Oxygen evolution and reduction reactions are fundamental processes in biological energy conversion schemes, which represent an attractive method for artificial energy conversion for a world still largely depending on fossil fuels. A range of metalloenzymes achieve these challenging tasks in biology by activating water and dioxygen using cheap and abundant transition metals, such as iron, copper, and manganese. High-valent metal–oxo/oxyl, metal–superoxo, and/or metal–(hydro)peroxo species are common reactive intermediates that are found in the O–O bond formation and activation reactions. The transient nature of the metal–oxygen intermediates has, however, prevented their isolation and characterization in most cases. As a consequence, unambiguous mechanistic assignments in the O–O bond formation and cleavage processes in biological and chemical entries remain elusive, especially for the intermediates and mechanisms involved in the O–O bond formation reactions. This viewpoint article aims at summarizing the information obtained to date in enzymatic and biomimetic systems that fuels the debate regarding the nature of the active oxidants and the mechanistic uncertainties associated with the transition metal-mediated O–O bond formation and cleavage reactions.

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.

In this study, W-(Y0.9La0.1)2O3 composite powders are fabricated by means of a combination of wet chemical method and spark plasma sintering. We systematically study the sintering and densification behavior of W-(Y0.9La0.1)2O3 composite powders at different temperatures and pressures. The results indicate that ultrafine tungsten-based composites with a dispersed distribution of (Y0.9La0.1)2O3 particles can be achieved under optimized temperature and pressure conditions. The optimized pressure and sintering temperature for W-(Y0.9 La0.1)2O3 composites are identified to be 75 MPa and 1600 °C, respectively. In addition, the surface damage behavior of W-(Y0.9La0.1)2O3 composites induced by the laser thermal shock and helium ion irradiation are also investigated. It is shown that the presence of holes greatly enlarges the helium retention during helium ion irradiation and promotes the melting caused by local overheating during laser thermal shock. We find that the fine-dispersed distribution of (Y0.9La0.1)2O3 particles in the tungsten-based composites can effectively improve the resistance of helium ion irradiation and laser thermal shock. We hope that these findings could provide some guidance and reference for the fabrication of large-sized tungsten-based materials in fusion engineering.

During decay, the sediment microenvironment and water quality are severely affected by excessive proliferation of harmful algae such as filamentous green algae (FGA). The frequency of this FGA is increased through global warming and water eutrophication. In the present study, the degradation processes of a common advantage FGA Cladophora oligoclora and its effect on nitrogen and phosphorus nutrient structure and bacterial community composition at the sediment-water interface were investigated by stable isotope labelling and high-throughput sequencing. The results showed that the decomposition process of C. oligoclona was fast, stable, and difficult to degrade. The changes in sediment δ15N values reached 66.68 ‰ on day 40, which indicated that some of the nitrogen had migrated to the sediment from C. oligoclona litter. TN and NH4+-N in the overlying water rapidly increased between days 0-10, NH4+-N rose to 78.21% of TN on day 40, resulting in severe pollution of ammonia in the overlying water. The nitrogen forms and contents in the sediment are mainly derived from the increasing ammonia nitrogen release. The TP and IP in the overlying water increased to the highest concentrations of 6.68±0.64, 6.59±0.79 mg·L-1 during the decomposition process, respectively, resulting in the migration of phosphate to the sediments with increasing phosphorus content. The abundance of the main dominant bacterial communities, such as Acinetobacter (0.08%-62.48%) and Pseudomonas (0.13%-20.36%) in sediments and overlying water has changed significantly. The correlation analysis results suggested that the phosphorus was mainly related to the bacterial community in the overlying water, while the various forms of nitrogen demonstrated a high relevance with the bacterial community in the sediment. Our research results will be valuable in evaluating the potential ecological risk of FGA decomposition and provide scientific support for shallow lake management and submerged vegetation restoration.

Bromodomain protein 4 (BRD4) plays a crucial role in transcriptional regulation and is considered to be a viable drug target for cancer treatment. Herein, we designed and synthesized a series of indole-2-one derivatives through scaffold hopping drug design. Most of the compounds showed potent BRD4 inhibitory activities and anti-proliferation activities in cancer cell lines. Especially, compound 12j exhibited excellent BRD4 inhibitory activities (BD1 IC50 = 19 nM, BD2 IC50 = 28 nM) and anti-proliferation potency with IC50 values of 4.75 μM and 1.35 μM in HT-29 and HL-60 cells, respectively. Additionally, docking studies showed that the hydrophobic pocket next to KAc region and WPF shelf were critical to the activity of the compound. Compound 12j could arrest the cell-cycle progression of HT-29 cells into the G1 phase and reduce the expression of c-Myc. Moreover, compound 12j exhibited favorable oral pharmacokinetic properties. All the results demonstrated that compound 12j was a potent BRD4 inhibitor and had merely potential for colon cancer treatment.

Pioglitazone (PIO) attenuates cisplatin nephrotoxicity whereas the underlying mechanism remains unknown. Apoptosis is associated with mitochondrial dysfunction and SIRT1 activation can decrease cell apoptosis in cisplatin nephrotoxicity. Therefore, we explored whether the protective effect of PIO in cisplatin nephrotoxicity is achieved by suppressing mitochondria‐mediated apoptosis through SIRT1/p53 signalling regulation. Cell viability, apoptosis, survival rate, renal pathology and function were examined. Moreover, we also analysed the expression of SIRT1, Acetyl‐p53, mitochondrial membrane potential (MMP), reactive oxygen species (ROS), mitochondrial permeability transition pore (mPTP) opening, adenosine triphosphate (ATP) and apoptosis‐related protein in vivo and in vitro. Pioglitazone treatment significantly increased cell viability, promoted SIRT1‐p53 interaction, upregulated Bcl‐2 expression, activated SIRT1 and elevated mitochondrial ATP synthesis after cisplatin treatment. However, PIO decreased the generation of ROS, opening of mPTP, dissipation of MMP and translocation of cytochrome c after cisplatin treatment. Pioglitazone also reduced the activation of caspase‐3 and caspase‐9, lowered the ratio of Bax/Bcl‐2, attenuated kidney pathological damage and dysfunction, down‐regulated the expression of Acetyl‐p53, PUMA‐α and Bax and abated cell apoptosis after cisplatin treatment. The SIRT1 inhibitor, EX527, clearly reversed the protective effects of PIO. These results implied PIO attenuated cisplatin nephrotoxicity by suppressing mitochondria‐mediated apoptosis through regulating SIRT1/p53 signalling.

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.

Objectives To investigate the effect and mechanism of macrophage activation and graft damage caused by nucleoside triphosphate diphosphohydrolase 1 (NTPDase1) in acute antibody-mediated rejection (AMR). Methods Acute AMR was induced in different skin-grafted nude mouse models with wild-type NTPDase1 expression, transgene-enhanced NTPDase1 expression, or NTPDase1 gene knockout. Several methods (eg, real-time fluorescence quantitative polymerase chain reaction, high-performance liquid chromatography [HPLC], immunofluorescence, flow cytometry, and luciferin/luciferase assays) were used to study (at the histologic and molecular levels) the extracellular adenosine diphosphate (ADP) concentration, macrophage proliferation, major histocompatibility complex (MHC) class II antigen expression on the surface of macrophages, B-cell activating factor (BAFF) expression in the peripheral blood serum, and the total number of SmIg-positive B cells during acute AMR. The relative activity of NTPDase1 in B cells and epithelial cells, pathologic changes, and the incidence of positive C4d deposition around the capillaries of skin grafts on the different nude mice were studied. Results Macrophages proliferated significantly when acute AMR occurred. The higher the NTPDase1 expression level, the lower the extracellular ADP concentration, the expression of MHC class II antigens on the surface of macrophages, the expression of BAFF in the peripheral blood serum, and the total number of SmIg-positive B cells, indicating negative correlations. The relative activity of NTPDase1 in B cells and epithelial cells of the skin graft was different among the different mice. The higher the NTPDase1 expression level, the lower the degree of pathologic damage to the skin graft. Conclusions Imbalance in extracellular ADP degradation by NTPDase1 may promote macrophage activation, and activated macrophages may be an important cause of graft damage.

Tudor staphylococcal nuclease (Tudor-SN) is a multifunctional protein involved in a variety of cellular processes and plays a critical role in the regulation of gene expression. Recently, Tudor-SN was found to be upregulated in mammary epithelial cells during lactation in response to prolactin, which further to regulate milk protein synthesis. However, the detailed regulatory mechanism of Tudor-SN to milk protein still remains to be elucidated. In our study, we observed that the levels of Tudor-SN and phosphor-Tudor-SN (Thr103) were both enhanced upon prolactin stimulation. Immunofluorescence assays demonstrated that prolactin treatment facilitated the nuclear transport of Tudor-SN. Further study revealed that the phosphorylation of Tudor-SN was depended on activated JNK. Coimmunoprecipitation assays disclosed that Tudor-SN might be phosphorylated directly by JNK. Using gene mutation assays, we further discovered that mutation of Thr to Ala at site of 103 prevented the nuclear transport of Tudor-SN. Thus, these results suggested the essential mechanism of the activated Tudor-SN in milk protein regulation in response to prolactin, which may provide some new sights into improve milk protein production.

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.