ABSTRACT
Although thermosonication (TS) treatment has been widely used in food sterilization, the viable but non-culturable (VBNC) of bacteria with TS treatment has still concerned potential food safety and public health. The molecular mechanism of VBNC status of bacteria with TS treatment is not clearly known. Therefore, in this study, we used Shewanella putrefaciens, which was a common putrefactive bacteria in aquatic products, to study the VBNC state of bacteria with TS treatment. Firstly, our results revealed that S. putrefaciens still could enter the VBNC state after TS treatments: 50 kHz, 300 W, 30 min ultrasonic treatment and 70 °C heating; Subsequently, we found the VBNC state of S. putrefaciens can resist the damage of TS treatment, such as cell wall break, DNA degradation, etc; Finally, four-dimensional data-independent acquisition-based proteomics showed that under VBNC state, S. putrefaciens upregulated functional proteins to resist TS treatment, such as: ribosomal proteins to accelerate the synthesis of stress proteins to counteract TS treatments, ornithine decarboxylase SpeF and MraY to repair TS treatment-induced damage, etc. Meanwhile, S. putrefaciens downregulates metabolic and transport functional proteins such as dehydrogenase to reduce the metabolism. Importantly, among those proteins, the ribosomal transcriptional regulatory protein family, such as rpsB, etc, may be the key proteins for S. putrefaciens entering VBNC state. This finding can provide some new strategies for preventing VBNC status of bacteria with TS treatment, such as: inhibition of key proteins, etc.
ABSTRACT
Providing antioxidants and targeting acetylcholinesterase (AChE) are key strategies in treating neurocognitive dysfunction. In this study, bioactive sturgeon (Acipenser schrenckii) spinal cord peptides (SSCPs) with antioxidant and AChE inhibitory potency were extracted and separated from sturgeon spinal cord by enzymatic hydrolysis and ultrafiltration, and targeted peptide PGGW was screened via computer simulated molecular docking. Further, the molecular dynamic interactions of the PGGW with superoxide dismutase (SOD) and AChE were analyzed, and the protective effect of PGGW on glutamate-induced PC12 cells in vitro was evaluated. The <3 kDa fraction of SSCPs displays the most potent antioxidative efficacy (1 mg/mL, DPPHâ¢: 89.07%, ABTS+: 76.35%). Molecular dynamics simulation showed that PGGW was stable within AChE and tightly bound to residues SER203, PHE295, ILE294 and TRP236. When combined with SOD, the indole group of PGGW was stuck inside SOD, but the tail chain PGG fluctuated greatly outside. Surface plasmon resonance demonstrated that PGGW has a high binding affinity for AChE (KD = 1.4 mM) and 0.01 mg/mL PGGW provided good protection against glutamate-induced apoptosis. The findings suggest a promising strategy for drug research on neurodegenerative diseases.
ABSTRACT
Effectively and completely eliminating residual tumor cells is the key to reducing the risk of tumor metastasis and recurrence. Designing an "ideal" nanoplatform for programmable cancer therapy has great prospects for completely eliminating residual tumor cells. Herein, an intelligent nanoplatform of disulfiram (DSF)-loaded CuS-tannic acid nanohexahedrons (denoted as "DSF-CuS@TA") with thermal- and pH-sensitive degradation, as well as near-infrared (NIR-II) phototherapeutics properties, was constructed. And then, it was employed for in situ DSF toxification activation programmable "triple attack" cancer therapy. After accumulating in the tumor, DSF-CuS@TA first releases the loaded Cu(DTC)2, and simultaneously degrades and releases Cu2+ and DSF under mildly acidic stimulation to trigger instant intratumoral Cu(DTC)2 chelation, thereby achieving the "first strike." Next, under irradiation by a NIR-II laser, light energy is converted into heat to generate NIR-II photothermal therapy, thereby achieving the second strike. Subsequently, under thermal stimulation, DSF-CuS@TA degrades further, triggering the chelation of Cu(DTC)2 for a second time to reach the third strike. As expected, in vitro and in vivo studies showed that the synergistic integration of DSF-based programmed chemotherapy and NIR-II phototherapeutics could achieve effective tumor removal. Therefore, we propose a novel type of programmed therapy against cancer by designing a nanoplatform via "nontoxicity-to-toxicity" chemical chelation transformation.
ABSTRACT
Systemic lupus erythematosus (SLE) is a common autoimmune disease, and its pathogenesis mainly involves the aberrant activation of B cells through follicular helper T (Tfh) cells to produce pathogenic antibodies, which requires more effective and safe treatment methods. Dihydroartemisinin (DHA) is the main active ingredient of artemisinin and has immunosuppressive effects. In this study, in vitro experiments confirmed that DHA inhibited Tfh cell induction and weakened its auxiliary function in B cell differentiation; furthermore, DHA directly inhibited B cell activation, differentiation, and antibody production. Furthermore, a mouse model of SLE was established, and we confirmed that DHA significantly reduced the symptoms of SLE and lupus nephritis, and decreased serum immunoglobulin (Ig)G, IgM, IgA, and anti-dsDNA levels. Moreover, DHA reduced the frequencies of total Tfh cells, activated Tfh cells, and B cell lymphoma 6, and interleukin (IL)-21 levels in Tfh cells from the spleen and lymph nodes, as well as the levels of B cells, germinal center B cells, and plasma cells in the spleen, lymph nodes, and kidneys. Additionally, DHA inhibited Tfh cells by blocking IL-2-inducible T cell kinase (ITK) signaling and its downstream nuclear factor (NF)-κB, nuclear factor of activated T cell, and activating protein-1 pathways, and directly inhibited B cells by blocking Bruton's tyrosine kinase (BTK) signaling and the downstream NF-κB and Myc pathways. Overall, our results demonstrated that DHA inhibited Tfh cells by blocking ITK signaling and also directly inhibited B cells by blocking BTK signaling. Therefore, reducing the production of pathogenic antibodies might effectively treat SLE.
Subject(s)
Artemisinins , B-Lymphocytes , Lupus Erythematosus, Systemic , Artemisinins/pharmacology , Animals , Lupus Erythematosus, Systemic/drug therapy , Lupus Erythematosus, Systemic/immunology , Lupus Erythematosus, Systemic/metabolism , Mice , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , T-Lymphocytes, Helper-Inducer/drug effects , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Helper-Inducer/metabolism , Female , T Follicular Helper Cells/immunology , T Follicular Helper Cells/drug effects , T Follicular Helper Cells/metabolism , Disease Models, Animal , Cell Differentiation/drug effectsABSTRACT
Developing an efficient method for screening Ochratoxin A (OTA) in agriculture products is vital to ensure food safety and human health. However, the complex food matrix seriously affects the sensitivity and accuracy. To address this issue, we designed a novel molecularly imprinted polymer (MIP) electrochemical sensor based on multiwalled carbon nanotube-modified niobium carbide (Nb2C-MWCNTs) with the aid of the density functional theory (DFT). In this design, a glassy carbon electrode (GCE) was first modified by Nb2C-MWCNTs heterostructure. Afterward, the MIP layer was prepared, with ortho-toluidine as a functional monomer selected via DFT and OTA acting as a template on the surface of Nb2C-MWCNTs/GCE using in-situ electropolymerization. Electrochemical tests and physical characterization revealed that Nb2C-MWCNTs improved the sensor's active surface area and electron transmission capacity. Nb2C-MWCNTs had a good synergistic effect on MIP, endowing the sensor with high sensitivity and specific recognition of OTA in complex food matrix systems. The MIP sensor showed a wide linear range from 0.04 to 10.0 µM with a limit of detection (LOD) of 3.6 nM. Moreover, it presented good repeatability and stability for its highly antifouling effect on OTA. In real sample analysis, the recoveries, ranging from 89.77% to 103.70%, agreed well with the results obtained by HPLC methods, suggesting the sensor has good accuracy and high potential in practical applications.
Subject(s)
Electrochemical Techniques , Food Contamination , Limit of Detection , Molecular Imprinting , Molecularly Imprinted Polymers , Nanotubes, Carbon , Ochratoxins , Ochratoxins/analysis , Ochratoxins/chemistry , Nanotubes, Carbon/chemistry , Electrochemical Techniques/instrumentation , Food Contamination/analysis , Molecularly Imprinted Polymers/chemistry , ElectrodesABSTRACT
In this study, a series of Fe-based materials are facilely synthesized using MIL-88A and melamine as precursors. Changing the mass ratio of melamine and MIL-88A could tune the coating layers of generated zero-valent iron (Fe0) particles from Fe3C to Fe3N facilely. Compared to Fe/Fe3N@NC sample, Fe/Fe3C@NC exhibits better catalytic activity and stability to degrade carbamazepine (CBZ) with peroxymonosulfate (PMS) as oxidant. Free radical quenching tests, open-circuit potential (OCP) test and electron paramagnetic resonance spectra (EPR) prove that hydroxyl radicals (OH) and superoxide radical (O2-) are dominant reactive oxygen species (ROSs) with Fe/Fe3C@NC sample. For Fe/Fe3N@NC sample, the main ROSs are changed into sulfate radicals (SO4-) and high valent iron-oxo (Fe (IV)=O) species. In addition, the better conductivity of Fe3C is beneficial for the electron transfer from Fe0 to the Fe3C, thus could keep the activity of the surface sites and obtain better stability. DFT calculation reveals the better adsorption and activation ability of Fe3C than Fe3N. Moreover, PMS can also be adsorbed on the Fe sites of Fe3N with shorter FeO bonds and longer SO bonds than on Fe3C, the Fe (IV)=O is thus present in the Fe/Fe3N@NC/PMS system. This study provides a novel strategy for the development of highly active Fe-based materials for Fenton-like reactions and thus could promote their real application.
ABSTRACT
Fluorescent imaging and biosensing in the near-infrared-II (NIR-II) window holds great promise for non-invasive, radiation-free, and rapid-response clinical diagnosis. However, it's still challenging to develop bright NIR-II fluorophores. In this study, we report a new strategy to enhance the brightness of NIR-II aggregation-induced emission (AIE) fluorophores through intramolecular electrostatic locking. By introducing sulfur atoms into the side chains of the thiophene bridge in TSEH molecule, the molecular motion of the conjugated backbone can be locked through intramolecular interactions between the sulfur and nitrogen atoms. This leads to enhanced NIR-II fluorescent emission of TSEH in both solution and aggregation states. Notably, the encapsulated nanoparticles (NPs) of TSEH show enhanced brightness, which is 2.6-fold higher than TEH NPs with alkyl side chains. The in vivo experiments reveal the feasibility of TSEH NPs in vascular and tumor imaging with a high signal-to-background ratio and precise resection for tiny tumors. In addition, polystyrene nanospheres encapsulated with TSEH are utilized for antigen detection in lateral flow assays, showing a signal-to-noise ratio 1.9-fold higher than the TEH counterpart in detecting low-concentration antigens. This work highlights the potential for developing bright NIR-II fluorophores through intramolecular electrostatic locking and their potential applications in clinical diagnosis and biomedical research.
Subject(s)
Fluorescent Dyes , Infrared Rays , Optical Imaging , Static Electricity , Fluorescent Dyes/chemistry , Humans , Nanoparticles/chemistry , Thiophenes/chemistry , Animals , Mice , Molecular StructureABSTRACT
Starvation therapy has shown promise as a cancer treatment, but its efficacy is often limited when used alone. In this work, a multifunctional nanoscale cascade enzyme system, named CaCO3@MnO2-NH2@GOx@PVP (CMGP), was fabricated for enhanced starvation/chemodynamic combination cancer therapy. CMGP is composed of CaCO3 nanoparticles wrapped in a MnO2 shell, with glucose oxidase (GOx) adsorbed and modified with polyvinylpyrrolidone (PVP). MnO2 decomposes H2O2 in cancer cells into O2, which enhances the efficiency of GOx-mediated starvation therapy. CaCO3 can be decomposed in the acidic cancer cell environment, causing Ca2+ overload in cancer cells and inhibiting mitochondrial metabolism. This synergizes with GOx to achieve more efficient starvation therapy. Additionally, the H2O2 and gluconic acid produced during glucose consumption by GOx are utilized by MnO2 with catalase-like activity to enhance O2 production and Mn2+ release. This process accelerates glucose consumption, reactive oxygen species (ROS) generation, and CaCO3 decomposition, promoting the Ca2+ release. CMGP can alleviate tumor hypoxia by cycling the enzymatic cascade reaction, which increases enzyme activity and combines with Ca2+ overload to achieve enhanced combined starvation/chemodynamic therapy. In vitro and in vivo studies demonstrate that CMGP has effective anticancer abilities and good biosafety. It represents a new strategy with great potential for combined cancer therapy.
Subject(s)
Calcium Carbonate , Glucose Oxidase , Manganese Compounds , Oxides , Glucose Oxidase/metabolism , Glucose Oxidase/chemistry , Glucose Oxidase/pharmacology , Manganese Compounds/chemistry , Manganese Compounds/pharmacology , Oxides/chemistry , Oxides/pharmacology , Humans , Animals , Calcium Carbonate/chemistry , Calcium Carbonate/pharmacology , Calcium Carbonate/metabolism , Mice , Antineoplastic Agents/pharmacology , Antineoplastic Agents/chemistry , Nanoparticles/chemistry , Povidone/chemistry , Povidone/pharmacology , Tumor Hypoxia/drug effects , Reactive Oxygen Species/metabolism , Cell Survival/drug effects , Particle Size , Cell Line, Tumor , Hydrogen Peroxide/metabolism , Cell Proliferation/drug effects , Drug Screening Assays, Antitumor , Surface Properties , Mice, Inbred BALB CABSTRACT
Herein, a new heterogeneous CoSe2-x@NC material with abundant selenium vacancies is synthesized via an in-situ carbonization-selenization process from cobaltic metal organic framework (Co-MOF). The obtained CoSe2-x@NC has a unique electronic structure and rich active sites, which can activate peroxymonosulfate (PMS) to degrade carbamazepine (CBZ) with superior catalytic performance and stability. The quenchingexperiments and EPR test show that SO4â¢- is the dominant reactive oxidation species (ROSs) for CBZ degradation. Significantly, systemic electrochemical tests and theoretical calculations illustrated that the dominant role of SO4â¢- is attributed to the existence of abundant selenium vacancies in CoSe2-x@NC, which can adjust the density of electron cloud of the Co atoms in CoSe2-x@NC to improve the PMS adsorption and promoting the conversion of transition metallic redox pairs (Co3+/Co2+). This work provides a facile way to improve the activity and stability of CoSe2 by defect engineering in the PMS based advanced oxidation process (AOPs).
ABSTRACT
Chronic rejection is the primary cause of late allograft failure, however, the current treatments for chronic rejection have not yielded desirable therapeutic effects. B cell activation and donor-specific antibody (DSA) production are the primary factors leading to chronic rejection. Bruton's tyrosine kinase (BTK) plays a key role in the activation and differentiation of B cells and in antibody production. This study investigated the efficacy of blocking BTK signalling in the prevention of chronic rejection. BTK signalling was blocked using the BTK inhibitor ibrutinib and gene knockout. In vitro assays were conducted to examine the consequences and underlying mechanisms of BTK blockade in regards to B cell activation, differentiation, and antibody secretion. Additionally, we established a cardiac transplantation mouse model of chronic rejection to explore the preventive effects and mechanisms of BTK ablation on chronic rejection. Ablating BTK signalling in vitro resulted in the inhibition of B cell activation, differentiation, and antibody production. In vivo experiments provided evidence that ablating BTK signalling alleviated chronic rejection, leading to reduced damage in myocardial tissue, neointimal hyperplasia, interstitial fibrosis, inflammatory cell infiltration, and C4d deposition. Allograft survival was prolonged, and B cell responses and DSA production were inhibited as a result. We confirmed that ablation of BTK signalling inhibited B cell response by blocking downstream PLCγ2 phosphorylation and inhibiting the NF-κB, NFAT, and ERK pathways. Our findings demonstrated that ablation of BTK signalling inhibited B cell activation and differentiation, reduced DSA production, and effectively prevented chronic rejection.
Subject(s)
Antibody Formation , Heart Transplantation , Animals , Mice , Agammaglobulinaemia Tyrosine Kinase , B-Lymphocytes , Signal TransductionABSTRACT
Chronic diabetic wounds remain a worldwide challenge for both the clinic and research. Given the vicious circle of oxidative stress and inflammatory response as well as the impaired angiogenesis of the diabetic wound tissues, the wound healing process is disturbed and poorly responds to the current treatments. In this work, a nickel-based metal-organic framework (MOF, Ni-HHTP) with excellent antioxidant activity and proangiogenic function is developed to accelerate the healing process of chronic diabetic wounds. The Ni-HHTP can mimic the enzymatic catalytic activities of antioxidant enzymes to eliminate multi-types of reactive species through electron transfer reactions, which protects cells from oxidative stress-related damage. Moreover, this Ni-based MOF can promote cell migration and angiogenesis by activating transforming growth factor-ß1 (TGF-ß1) in vitro and reprogram macrophages to the anti-inflammatory phenotype. Importantly, Ni-HHTP effectively promotes the healing process of diabetic wounds by suppressing the inflammatory response and enhancing angiogenesis in vivo. This study reports a versatile and promising MOF-based nanozyme for diabetic wound healing, which may be extended in combination with other wound dressings to enhance the management of diabetic or non-healing wounds.
Subject(s)
Diabetes Mellitus, Experimental , Metal-Organic Frameworks , Animals , Reactive Oxygen Species , Metal-Organic Frameworks/pharmacology , Nickel , Angiogenesis , Wound Healing/physiology , Antioxidants , HydrogelsABSTRACT
BACKGROUND: Chronic rejection, closely related to the activation of B cells and donor-specific antibody (DSA) production, has unsatisfactory therapeutic outcomes. B lymphocyte stimulator (BLyS) is a major regulatory factor that controls the activation and differentiation of B cells. However, it remains unclear whether BLyS blockade can regulate B and plasma cells in the transplantation setting and affect chronic rejection. Here, we investigated the efficacy of the BLyS inhibitors belimumab and telitacicept in controlling B-cell response and preventing chronic rejection. METHODS: The effects of belimumab and telitacicept on B-cell activation, differentiation, and antibody production in vitro were determined. A chronic rejection model in mouse was established by allogeneic cardiac transplantation with CTLA4-Ig treatment. Allograft survival, histology, DSA levels, and B-cell responses were analyzed to evaluate the chronic rejection-preventive effects of belimumab and telitacicept. RESULTS: In vitro experiments confirmed that belimumab and telitacicept inhibited B-cell activation and differentiation and reduced antibody production. In vivo experiments indicated that they significantly prolonged allograft survival, attenuated chronic rejection through significant suppression of myocardial ischemic necrosis and interstitial fibrosis, and reduced DSA-IgG levels, C4d deposition, and inflammatory cell infiltration. Furthermore, the frequencies of B cells, plasma cells, and IgG-producing cells in the recipients' spleen, lymph nodes, bone marrow, and blood were decreased after BLyS inhibitors treatment. CONCLUSIONS: This study demonstrated that belimumab and telitacicept inhibit B-cell responses and antibody production and alleviate chronic transplant rejection. Therefore, BLyS inhibitors are expected to be used for the prevention of chronic rejection in clinical practice.
Subject(s)
Antibody Formation , B-Cell Activating Factor , Mice , Animals , Graft Rejection/prevention & control , B-Lymphocytes , Immunoglobulin GABSTRACT
Anterior cruciate ligament (ACL) injury, a common sports injury, is associated with a high risk of subsequent osteoarthritis (OA), which can cause serious pain and disability. Understanding the detailed mechanism underlying the predisposition of knee with ACL injury to secondary OA at an early stage is key to preventing future degradation and progression to a clinically significant disease. A total of 56 male Sprague Dawley rats (age, 8 weeks; weight, 180-220 g) were randomly divided into three experimental groups: control, ACL transection (ACLT; where surgical procedure was performed with ACLT), and sham (where surgical procedure was performed without ACLT). The ACLT and sham groups were further divided into three subgroups based on when the rats were sacrificed: 4, 8, and 12 weeks after the surgical procedure. The control group and the aforementioned subgroups contained 8 rats each. We used nuclear magnetic resonance (NMR)-based metabolomic analysis to analyze rat serum samples for the metabolic characteristics and the underlying mechanisms. In total, 28 metabolites were identified in the NMR spectra of the rat sera. At 4 and 8 weeks postoperatively, the sham group demonstrated metabolic profiles different from those of the ACLT group. However, this difference was not observed 12 weeks postoperatively. In total, five metabolites (acetate, succinate, sn-glycero-3-phosphocholine, glucose, and phenylalanine) and five metabolic pathways (phenylalanine, tyrosine, and tryptophan biosynthesis; phenylalanine metabolism; pyruvate metabolism; starch and sucrose metabolism; and histidine metabolism) demonstrated significant differences between the ACLT and sham groups. ACL injury was noted to considerably affect biochemical homeostasis and metabolism; however, these metabolic changes persisted briefly. Moreover, glucose was a characteristic metabolite, and several energy-related metabolic pathways were significantly disturbed. Therefore, an ACL injury may lead to considerable impairments in energy metabolism. Abnormal glucose levels facilitate chondrocyte function impairment and thereby lead to OA progression. Furthermore, lactate may aid in identifying metabolic changes specific to knee trauma not related to an ACL injury. Overall, the metabolic changes in rat serum after an ACL injury were closely related to disturbances in energy metabolism and amino acid metabolism. The current results may aid in understanding the pathogenesis of posttraumatic osteoarthritis.
Subject(s)
Anterior Cruciate Ligament Injuries , Cartilage, Articular , Osteoarthritis , Rats , Male , Animals , Anterior Cruciate Ligament Injuries/metabolism , Rats, Sprague-Dawley , Osteoarthritis/pathology , Cartilage, Articular/pathology , Magnetic Resonance Spectroscopy , Glucose/metabolism , Phenylalanine/metabolismABSTRACT
Single-atom nanozymes (SAzymes) open new possibilities for the development of artificial enzymes that have catalytic activity comparable to that of natural peroxidase (POD). So far, most efforts have focused on the structural modulation of the Fe-N4 moiety to mimic the metalloprotein heme center. However, non-heme-iron POD with much higher activity, for example, HppE, has not been mimicked successfully due to its structural complexity. Herein, carbon dots (CDs)-supported SAzymes with twisted, nonplanar Fe-O3N2 active sites, highly similar to the non-heme iron center of HppE, was synthesized by exploiting disordered and subnanoscale domains in CDs. The Fe-CDs exhibit an excellent POD activity of 750 units/mg, surpassing the values of conventional SAzymes with planar Fe-N4. We further fabricated an activatable Fe-CDs-based therapeutic agent with near-infrared enhanced POD activity, a photothermal effect, and tumor-targeting ability. Our results represent a big step in the design of high-performance SAzymes and provide guidance for future applications for synergistic tumor therapy.
ABSTRACT
The entity-relationship joint extraction model plays a significant role in entity relationship extraction. The existing entity-relationship joint extraction model cannot effectively identify entity-relationship triples in overlapping relationships. This paper proposes a new joint entity-relationship extraction model based on the span and a cascaded dual decoding. The model includes a Bidirectional Encoder Representations from Transformers (BERT) encoding layer, a relational decoding layer, and an entity decoding layer. The model first converts the text input into the BERT pretrained language model into word vectors. Then, it divides the word vectors based on the span to form a span sequence and decodes the relationship between the span sequence to obtain the relationship type in the span sequence. Finally, the entity decoding layer fuses the span sequences and the relationship type obtained by relation decoding and uses a bi-directional long short-term memory (Bi-LSTM) neural network to obtain the head entity and tail entity in the span sequence. Using the combination of span division and cascaded double decoding, the overlapping relations existing in the text can be effectively identified. Experiments show that compared with other baseline models, the F1 value of the model is effectively improved on the NYT dataset and WebNLG dataset.
ABSTRACT
Organic selenium has been widely studied as a nutritional supplement for animal feed. However, there are few studies on the effect of organic selenium on flesh quality. In this study, the effects of organic selenium (yeast selenium (YS), Se 0.002 mg/L) on the metabolism and protein expression in Micropterus salmoides muscle under temporary fasting condition (6 weeks) were investigated. The muscle structure was observed through a microscope, and regulatory pathways were analyzed using proteomics and metabolomics methods. Electron microscopy showed that YS made the muscle fibers of M. salmoides more closely aligned. Differential analysis identified 523 lipid molecules and 268 proteins. The numbers of upregulated and downregulated proteins were 178 and 90, respectively, including metabolism (46.15%), cytoskeleton (11.24%) and immune oxidative stress (9.47%), etc. Integrated analyses revealed that YS enhanced muscle glycolysis, the tricarboxylic acid cycle and oxidative phosphorylation metabolism. In the YS group, the content of eicosapentaenoic acid was increased, and that of docosahexaenoic acid was decreased. YS slowed down protein degradation by downregulating ubiquitin and ubiquitin ligase expression. These results suggest that organic selenium can improve M. salmoides muscle quality through the aforementioned pathways, which provides potential insights into the improvement of the quality of aquatic products, especially fish.
Subject(s)
Bass , Selenium , Animals , Selenium/pharmacology , Proteomics , Muscles , Metabolomics , UbiquitinsABSTRACT
Effect of stearic acid-based lipophilic emulsifiers (sorbitan monostearate (Span-60), sucrose ester S-170, and lactic acid esters of monoglycerides (LACTEM)) and oleic acid-based lipophilic emulsifiers (sorbitan monooleate (Span-80) and sucrose ester O-170) on the crystallization of fat blend and the stability of whipped cream were studied. Span-60 and S-170 possessed strong nucleation inducing ability and good emulsifying properties. Thus, tiny and uniform crystals were formed in fat blends, small and ordered fat globules were distributed in emulsions, and air bubbles were effectively wrapped in firmly foam structures. The crystallization of the fat blend and the stability of whipped cream were slightly modified by LACTEM due to its poor nucleation inducing ability and moderate emulsifying characteristic. Span-80 and O-170 had weak nucleation inducing ability and poor emulsifying properties, therefore, loose crystals were formed in fat blends and some big fat globules were separated in emulsions, thereby decreasing the stability of whipped creams.
Subject(s)
Emulsifying Agents , Oleic Acid , Emulsions/chemistry , Crystallization , Emulsifying Agents/chemistry , Monoglycerides/chemistry , EstersABSTRACT
Fish is an important source of antimicrobial peptides. This study aimed to identify and screen antibacterial peptides with excellent antibacterial activity derived from sturgeon spermary peptides (SSPs) and to analyze their antibacterial activity and mechanism. Liquid chromatography-mass spectrometry/mass spectrometry methods were used to analyze and identify peptide sequences, computational prediction tool and molecular docking methods were used for virtual screening of antimicrobial peptides, and finally, candidate peptides were synthesized by solid-phase synthesis method. The results demonstrate that SSPs have excellent inhibitory activity against Escherichia coli with an inhibitory rate of 76.46%. Most parts of the SSPs were derived from the sturgeon (Acipenser ruthenus) histones, and the coverage of histone H2B was the highest (45%). Two novel peptides (NDEELNKLM and RSSKRRQ) were obtained by in silico prediction tools and molecular docking, which may interact with the DNA gyrase and dihydrofolate reductase of E. coli by forming salt bridges and hydrogen bonds. Compared to the individual peptides, the antibacterial effect was significantly improved by mixing the two peptides in equal proportions. Two novel peptides change the permeability of the E. coli cell membranes and may exert antimicrobial activity by inhibiting the metabolic process of the nucleic acids.
Subject(s)
Antimicrobial Peptides , Escherichia coli , Animals , Molecular Docking Simulation , Peptides/pharmacology , Peptides/chemistry , Fishes , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistryABSTRACT
In this study, a composite film was prepared using irradiated chitosan, lysozyme, and carrageenan for crayfish preservation. First, the chitosan was degraded by gamma rays, with the best antimicrobial properties being found at 100 KGy. By using the response surface method, the components of the composite film were irradiated chitosan (CS) at 0.016 g/mL, lysozyme (LM) at 0.0015 g/mL, and carrageenan (CA) at 0.002 g/mL. When compared to the natural chitosan film, the Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) results demonstrated that the chemical properties of the composite film did not change with the addition of LM and CA, while the physical and antibacterial properties increased, including tensile strength (16.87 â 20.28 N), hydrophobicity (67.9 â 86.3°), and oxygen permeability (31.66 â 24.31 m3·um/m2·day·kPa). Moreover, the antibacterial activity of the films increased with the addition of LM and CA, especially for Shewanella putrefaciens: the zone of inhibition (mm) of CS, CS/LM, and CS/LM/CA was 9.97 ± 0.29, 14.32 ± 0.31, and 14.78 ± 0.21, respectively. Finally, the CS/LM/CA film could preserve crayfish for 10 days at 4 °C, whereas the polyethylene (PE) film could only preserve them for 6 days. Moreover, the composite film was excellent at inhibiting oxidative deterioration (TBARS value: 2.12 mg/kg, day10) and keeping the texture of crayfish muscle. Overall, our results suggested that the CS/LM/CA composite film produced can be applied as a biodegradable film in aquatic product packaging.
ABSTRACT
The uncontrolled growth of dendrites and serious side reactions, such as hydrogen evolution and corrosion, significantly hinder the industrial application and development of aqueous zinc-ion batteries (ZIBs). This article presents ovalbumin (OVA) as a multifunctional electrolyte additive for aqueous ZIBs. Experimental characterizations and theoretical calculations reveal that the OVA additive can replace the solvated sheath of recombinant hydrated Zn2+ through the coordination water, preferentially adsorb on the surface of the Zn anode, and construct a high-quality self-healing protective film. Notably, the OVA-based protective film with strong Zn2+ affinity will promote uniform Zn deposition and inhibit side reactions. As a result, Zn||Zn symmetrical batteries in ZnSO4 electrolytes containing OVA achieve a cycle life exceeding 2200 h. Zn||Cu batteries and Zn||MnO2 (2 A g-1) full batteries show excellent cycling stability for 2500 cycles, demonstrating promising application prospects. This study provides insights into utilizing natural protein molecules to modulate the kinetics of Zn2+ diffusion and enhance the stability of the anode interface.