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1.
Small ; : e2405664, 2024 Oct 02.
Article in English | MEDLINE | ID: mdl-39358964

ABSTRACT

The integration of bio-based materials into triboelectric nanogenerators (TENGs) for energy harvesting from human body motions has sparked considerable research attention. Here, a silanated cellulose nanofibril (SCNF) aerogel is reported for structurally reliable TENGs and reversely compressible Taekwondo scoring sensors under repeated impacts. The preparation of the aerogel involves silanizing cellulose nanofibers (CNFs) with vinyltrimethoxysilane (VTMS), following by freeze-drying and post-heating treatment. The SCNF aerogel with crosslinked physico-chemical bonding and highly porous network is found to exhibit superior mechanical strength and reversible compressibility as well as enhanced water repellency and electron-donating ability. The TENG having a tribo-positive SCNF layer exhibits exceptional triboelectric performances, generating a voltage of 270 V, current of 11 µA, and power density of 401.1 mW m-2 under an applied force of 8 N at a frequency of 5 Hz. With its inherent merits in material composition, structural configuration, and device sensitivity, the SCNF TENG demonstrates the capability to seamlessly integrate into a Taekwondo protection gear, serving as an efficient self-powered sensor for monitoring hitting scores. This study highlights the significant potential of a facilely fabricated SCNF aerogel for the development of high-performance, bio-friendly, and cost-effective Bio-TENGs, enabling their application as self-powered wearable devices and sports engineering sensors.

2.
BMC Pediatr ; 24(1): 643, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39390439

ABSTRACT

BACKGROUND: The ability of socially assistive robots (SARs) to treat dementia and Alzheimer's disease has been verified. Currently, to increase the range of their application, there is an increasing amount of interest in using SARs to relieve pain and negative emotions among children in routine medical settings. However, there is little consensus regarding the use of these robots. OBJECTIVE: This study aimed to evaluate the effect of SARs on pain and negative affectivity among children undergoing invasive needle-based procedures. DESIGN: This study was a systematic review and meta-analysis of randomized controlled trials that was conducted in accordance with the Cochrane Handbook guidelines. METHODS: The PubMed, CINAHL, Web of Science, Cochrane Library, Embase, CNKI, and WanFang databases were searched from inception to January 2024 to identify relevant randomized controlled trials (RCTs). We used the Cochrane Risk of Bias tool 2.0 (RoB2.0) to assess the risk of bias among the included studies, and we used RevMan 5.4 software to conduct the meta-analysis. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) framework was used to assess the quality of the evidence. RESULTS: Ten RCTs involving 815 pediatric subjects were selected for this review and reported outcomes related to pain and emotions during IV placement, port needle insertion, flu vaccination, blood sampling, and dental treatment. Children undergoing needle-related procedures with SARs reported less anxiety (SMD= -0.36; 95% CI= -0.64, -0.09) and fewer distressed avoidance behaviors (SMD= -0.67; 95% CI= -1.04, -0.30) than did those receiving typical care. There were nonsignificant differences between these groups in terms of in pain (SMD = -0.02; 95% CI = - 0.81, 0.78) and fear (SMD = 0.38; 95% CI= -0.06, 0.82). The results of exploratory subgroup analyses revealed no statistically significant differences based on the intervention type of robots or anesthetic use. CONCLUSIONS: The use of SARs is a promising intervention method for alleviating anxiety and distress among children undergoing needle-related procedures. However, additional high-quality randomized controlled trials are needed to further validate these conclusions. TRIAL REGISTRATION: The protocol of this study has been registered in the database PROSPERO (registration ID: CRD42023413279).


Subject(s)
Needles , Robotics , Humans , Child , Randomized Controlled Trials as Topic , Pain, Procedural/etiology , Pain, Procedural/prevention & control , Pain Management/methods
3.
J Nanobiotechnology ; 22(1): 565, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39272089

ABSTRACT

Graphene oxide (GO), beyond its specialized industrial applications, is rapidly gaining prominence as a nanomaterial for modern agriculture. However, its specific effects on seed priming for salinity tolerance and yield formation in crops remain elusive. Under both pot-grown and field-grown conditions, this study combined physiological indices with transcriptomics and metabolomics to investigate how GO affects seed germination, seedling salinity tolerance, and peanut pod yield. Peanut seeds were firstly treated with 400 mg L⁻¹ GO (termed GO priming). At seed germination stage, GO-primed seeds exhibited higher germination rate and percentage of seeds with radicals breaking through the testa. Meanwhile, omics analyses revealed significant enrichment in pathways associated with carbon and nitrogen metabolisms in GO-primed seeds. At seedling stage, GO priming contributed to strengthening plant growth, enhancing photosynthesis, maintaining the integrity of plasma membrane, and promoting the nutrient accumulation in peanut seedlings under 200 mM NaCl stress. Moreover, GO priming increased the activities of antioxidant enzymes, along with reduced the accumulation of reactive oxygen species (ROS) in response to salinity stress. Furthermore, the differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) of peanut seedlings under GO priming were mainly related to photosynthesis, phytohormones, antioxidant system, and carbon and nitrogen metabolisms in response to soil salinity. At maturity, GO priming showed an average increase in peanut pod yield by 12.91% compared with non-primed control. Collectively, our findings demonstrated that GO plays distinguish roles in enhancing seed germination, mitigating salinity stress, and boosting pod yield in peanut plants via modulating multiple physiological processes.


Subject(s)
Arachis , Germination , Graphite , Salt Tolerance , Seedlings , Seeds , Arachis/metabolism , Arachis/drug effects , Arachis/physiology , Arachis/growth & development , Seeds/drug effects , Seeds/metabolism , Germination/drug effects , Seedlings/drug effects , Seedlings/growth & development , Seedlings/metabolism , Photosynthesis/drug effects , Gene Expression Regulation, Plant/drug effects , Reactive Oxygen Species/metabolism , Salinity , Transcriptome/drug effects , Antioxidants/metabolism
4.
Nat Commun ; 15(1): 8216, 2024 Sep 19.
Article in English | MEDLINE | ID: mdl-39294161

ABSTRACT

Atomically dispersed single atom (SA) and atomic cluster (AC) metallic materials attract tremendous attentions in various fields. Expanding monometallic SA and AC to multimetallic SA/AC composites opens vast scientific and technological potentials yet exponentially increasing the synthesis difficulty. Here, we present a general energy-selective-clustering methodology to build the largest reported library of carbon supported bi-/multi-metallic SA/AC materials. The discrepancy in cohesive energy results into selective metal clustering thereby driving the symbiosis of multimetallic SA or/and AC. The library includes 23 bimetallic SA/AC composites, and expanded compositional space of 17 trimetallic, quinary-metallic, septenary-metallic SA/AC composites. We chose bimetallic M1SAM2AC to demonstrate the electrocatalysis utility. Unique decoupled active sites and inter-site synergy lead to 8/47 mV overpotential at 10 mA cm-2 for alkaline/acidic hydrogen evolution and over 1000 h durability in water electrolyzer. Moreover, delicate modulations towards composition and configuration yield high-performance catalysts for multiple electrocatalysis systems. Our work broadens the family of atomically dispersed materials from monometallic to multimetallic and provides a platform to explore the complex composition induced unconventional effects.

5.
Proc Natl Acad Sci U S A ; 121(37): e2403421121, 2024 Sep 10.
Article in English | MEDLINE | ID: mdl-39226350

ABSTRACT

Drug-resistant Tuberculosis (TB) is a global public health problem. Resistance to rifampicin, the most effective drug for TB treatment, is a major growing concern. The etiological agent, Mycobacterium tuberculosis (Mtb), has a cluster of ATP-binding cassette (ABC) transporters which are responsible for drug resistance through active export. Here, we describe studies characterizing Mtb Rv1217c-1218c as an ABC transporter that can mediate mycobacterial resistance to rifampicin and have determined the cryo-electron microscopy structures of Rv1217c-1218c. The structures show Rv1217c-1218c has a type V exporter fold. In the absence of ATP, Rv1217c-1218c forms a periplasmic gate by two juxtaposed-membrane helices from each transmembrane domain (TMD), while the nucleotide-binding domains (NBDs) form a partially closed dimer which is held together by four salt-bridges. Adenylyl-imidodiphosphate (AMPPNP) binding induces a structural change where the NBDs become further closed to each other, which downstream translates to a closed conformation for the TMDs. AMPPNP binding results in the collapse of the outer leaflet cavity and the opening of the periplasmic gate, which was proposed to play a role in substrate export. The rifampicin-bound structure shows a hydrophobic and periplasm-facing cavity is involved in rifampicin binding. Phospholipid molecules are observed in all determined structures and form an integral part of the Rv1217c-1218c transporter system. Our results provide a structural basis for a mycobacterial ABC exporter that mediates rifampicin resistance, which can lead to different insights into combating rifampicin resistance.


Subject(s)
ATP-Binding Cassette Transporters , Bacterial Proteins , Cryoelectron Microscopy , Drug Resistance, Bacterial , Mycobacterium tuberculosis , Rifampin , Rifampin/pharmacology , Rifampin/metabolism , ATP-Binding Cassette Transporters/metabolism , ATP-Binding Cassette Transporters/chemistry , ATP-Binding Cassette Transporters/ultrastructure , ATP-Binding Cassette Transporters/genetics , Mycobacterium tuberculosis/metabolism , Mycobacterium tuberculosis/drug effects , Bacterial Proteins/metabolism , Bacterial Proteins/chemistry , Bacterial Proteins/ultrastructure , Bacterial Proteins/genetics , Models, Molecular , Adenylyl Imidodiphosphate/metabolism
6.
Int J Biol Macromol ; 280(Pt 2): 135884, 2024 Sep 22.
Article in English | MEDLINE | ID: mdl-39317292

ABSTRACT

Bio-composite foams based on Epoxidized Natural Rubber (ENR) filled with lignin (LG) and ammonium polyphosphate (APP) were fabricated via batch foaming. The addition of APP accelerated the foaming process at lower temperatures. Pre-mixing induced ionic and hydrogen bonding between the LG and the APP particles, which reduced crosslinking between LG and ENR. The resulting ENR bio-composite foams with LG/APP exhibited a significant increase in compressive strength (up to 700 %) and modulus (up to 600 %) compared to the ENR foam baseline. Furthermore, the LG/APP foams demonstrated lower thermal conductivity than both the ENR foam baseline and foams containing only LG or APP, attributed to optimal thermal conduction in the solid phase and convection within the pore cells. The combination of APP and LG produced synergistic effects, with phosphorus (from APP) and high carbon content (from LG) enhancing flame-retardant efficiency. This study highlights the potential of these sustainable bio-composite foams for applications requiring enhanced thermal insulation and flame retardancy attributes for insulation and other practical applications.

7.
Nat Commun ; 15(1): 8157, 2024 Sep 17.
Article in English | MEDLINE | ID: mdl-39289393

ABSTRACT

Intermetallic nanoparticles (NPs) possess significant potentials for catalytic applications, yet their production presents challenges as achieving the disorder-to-order transition during the atom ordering process involves overcoming a kinetic energy barrier. Here, we demonstrate a robust approach utilizing atomic gas-migration for the in-situ synthesis of stable and homogeneous intermetallic alloys for propane dehydrogenation (PDH). This approach relies on the physical mixture of two separately supported metal species in one reactor. The synthesized platinum-zinc intermetallic catalysts demonstrate exceptional stability for 1300 h in continuous propane dehydrogenation under industrially relevant industrial conditions, with extending 95% propylene selectivity and propane conversions approaching thermodynamic equilibrium values at 550-600 oC. In situ characterizations and density functional theory/molecular dynamics simulation reveal Zn atoms adsorb on the particle surface and then diffuse inward, aiding in the formation of ultrasmall and highly ordered intermetallic alloys. This in-situ gas-migration strategy is applicable to a wide range of intermetallic systems.

8.
ChemSusChem ; : e202401662, 2024 Sep 18.
Article in English | MEDLINE | ID: mdl-39295088

ABSTRACT

CO2 utilization is a critical aspect of achieving a sustainable carbon cycle, particularly in the context of global efforts to achieve carbon neutrality. Drawing inspiration from geological chemistry, Fe-based hydrothermal CO2 reduction into valuable chemicals has emerged as a promising CO2 utilization strategy. However, the lack of a sustainable and direct Fe regeneration approach presents a notable challenge to the widespread adoption of this strategy. Herein, we propose a method for the direct reduction of Fe3O4 to Fe using biodiesel-waste glycerol. This method yields a remarkable 97.9 wt% of reduced Fe, which exhibits a high activity for CO2 (HCO3-) reduction to formic acid, maintaining a level of ~90%. Our investigation reveals that the Fe3O4 reduction involves a direct hydrogen transfer from hydroxyl groups to lattice O atoms on the surface of Fe3O4, forming reductive H species. The presence of a polyhydroxy structure in glycerol facilitates the stabilization of surface H species, thereby enhancing the reduction efficiency process. These findings establish an efficient and sustainable Fe3O4/Fe redox cycle, which integrates waste biomass into circular carbon economy solutions and contributes to the overall net carbon benefit of CO2 utilization.

9.
Microorganisms ; 12(8)2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39203368

ABSTRACT

The economical and efficient commercial production of second-generation bioethanol requires fermentation microorganisms capable of entirely and rapidly utilizing all sugars in lignocellulosic hydrolysates. In this study, we developed a recombinant Saccharomyces cerevisiae strain, BLH510, through protoplast fusion and metabolic engineering to enhance its ability to co-ferment glucose, xylose, cellobiose, and xylooligosaccharides while tolerating various inhibitors commonly found in lignocellulosic hydrolysates. The parental strains, LF1 and BLN26, were selected for their superior glucose/xylose co-fermentation capabilities and inhibitor tolerance, respectively. The fusion strain BLH510 demonstrated efficient utilization of mixed sugars and high ethanol yield under oxygen-limited conditions. Under low inoculum conditions, strain BLH510 could completely consume all four kinds of sugars in the medium within 84 h. The fermentation produced 33.96 g/L ethanol, achieving 84.3% of the theoretical ethanol yield. Despite the challenging presence of mixed inhibitors, BLH510 successfully metabolized all four sugars above after 120 h of fermentation, producing approximately 30 g/L ethanol and reaching 83% of the theoretical yield. Also, strain BLH510 exhibited increased intracellular trehalose content, particularly under conditions with mixed inhibitors, where the intracellular trehalose reached 239.3 mg/g yeast biomass. This elevated trehalose content contributes to the enhanced stress tolerance of BLH510. The study also optimized conditions for protoplast preparation and fusion, balancing high preparation efficiency and satisfactory regeneration efficiency. The results indicate that BLH510 is a promising candidate for industrial second-generation bioethanol production from lignocellulosic biomass, offering improved performance under challenging fermentation conditions. Our work demonstrates the potential of combining protoplast fusion and metabolic engineering to develop superior S. cerevisiae strains for lignocellulosic bioethanol production. This approach can also be extended to develop robust microbial platforms for producing a wide array of lignocellulosic biomass-based biochemicals.

10.
Bioorg Med Chem Lett ; 112: 129932, 2024 Nov 01.
Article in English | MEDLINE | ID: mdl-39182737

ABSTRACT

Glycogen synthase kinase 3ß (GSK-3ß) is a potential therapeutic target for the treatment of a variety of human diseases. Here, we report the design and synthesis of a series of thieno[3,2-c]pyrazol-urea derivatives and evaluation of their GSK-3ß inhibitory activity. Among these analogues, the compound without substitution on terminal phenyl ring (3a) was found to be the most potent GSK-3ß inhibitor with an IC50 of 74.4 nM, while substitution on the terminal phenyl (3b-3p) led to decreased potency, independent of the position, size, or electronic properties of the substituents. Kinase selectivity assay revealed that 3a showed good selectivity over a panel of kinases, but was less selective over CDK1, CDK2 and CDK5. Additionally, the pharmacological properties of the synthesized compounds were investigated computationally by the SwissADME and the results showed that most of the compounds have good ADME profiles.


Subject(s)
Drug Design , Glycogen Synthase Kinase 3 beta , Protein Kinase Inhibitors , Pyrazoles , Urea , Pyrazoles/chemistry , Pyrazoles/pharmacology , Pyrazoles/chemical synthesis , Humans , Glycogen Synthase Kinase 3 beta/antagonists & inhibitors , Glycogen Synthase Kinase 3 beta/metabolism , Urea/pharmacology , Urea/analogs & derivatives , Urea/chemistry , Urea/chemical synthesis , Structure-Activity Relationship , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Molecular Structure , Glycogen Synthase Kinase 3/antagonists & inhibitors , Glycogen Synthase Kinase 3/metabolism , Dose-Response Relationship, Drug
11.
Front Nutr ; 11: 1459638, 2024.
Article in English | MEDLINE | ID: mdl-39206308

ABSTRACT

Objective: To investigate the associations between the geriatric nutritional risk index (GNRI) with cognitive functions among U.S. older adults. (Patients were classified into two nutrition risk groups based on the GNRI). Methods: Our analysis utilized data from the cross-sectional National Health and Nutrition Examination Survey (NHANES) conducted between 2011 and 2014. Cognitive function was measured using CERAD test, AFT and DSST. Composite z-scores were obtained by summing test-specific z-scores of the above three cognitive tests and were used to assess the global cognitive function. We employed weighted logistic regression models to evaluate the associations between GNRI and nutritional status (low and high GNRI) with cognitive function among older participants. The non-linear relationship was described using fitted smoothed curves and threshold effect analyses. Subgroup analysis and interaction tests were also conducted. Results: This study included 2,592 older participants aged 60 years and older. After adjusting for confounding variables, the GNRI was positively associated with AFT (ß = 0.05, 95% CI 0.005-0.096, p-value = 0.0285), DSST (ß = 0.192, 95% CI 0.078-0.305, p-value = 0.0010) and the composite z-scores (ß = 0.027, 95% CI 0.010-0.044, p-value = 0.0024). The results also showed that the high-GNRI group was significantly associated with AFT (ß = 0.922, 95% CI 0.166-1.677, p-value = 0.0169), DSST (ß = 2.791, 95% CI 0.884-4.698, p-value = 0.0042) and composite z-scores (ß = 0.405, 95% CI 0.115-0.695, p-value = 0.0062) likewise had significant positive correlations, using the low-GNRI group as a reference. In addition, inflection points with CERAD and composite z-scores were found at GNRI of 108.016, and 105.371, respectively. Specifically, on the left side of the inflection point GNRI levels were positively correlated with CERAD and composite z-scores (CERAD ß = 0.087, 95% CI 0.024-0.150, p-value = 0.0070; composite z-scores ß = 0.065, 95% CI 0.040-0.091, p-value <0.0001), while on the right side of the inflection point were significantly negatively associated (CERAD ß = -0.295, 95% CI -0.529 to -0.062, p-value = 0.0133, composite z-scores ß = -0.050, 95% CI -0.091 to -0.008, p-value = 0.0184). Conclusion: Lower GNRI was associated with poorer performance in several cognitive domains. Additionally, there was a non-linear positive association between GNRI and cognitive function in normal nutritional states, for excessive GNRI may cause cognitive decline.

12.
Chem Commun (Camb) ; 60(68): 9093-9096, 2024 Aug 20.
Article in English | MEDLINE | ID: mdl-39108100

ABSTRACT

Atomically dispersed cerium species, anchored to high-area alumina by unsaturated penta-coordinated aluminum, strongly interact with atomically dispersed Cu species to provide active centers for water-gas shift reaction (WGSR). The alumina-anchored Ce3+ species stabilize atomically dispersed Cu+ to form Cu+-Ce3+ active complexes and they work synergistically to enhance low-temperature WGSR activity. This work offers alternative approaches to developing low-cost catalysts for the WGSR process.

13.
Polymers (Basel) ; 16(15)2024 Jul 25.
Article in English | MEDLINE | ID: mdl-39125147

ABSTRACT

Isocyanates are critical components that affect the crosslinking density and structure of polyurethane (PU) foams. However, due to the cost and hazardous nature of the precursor for isocyanate synthesis, there is growing interest in reducing their usage in polyurethane foam production-especially in rigid PU foams (RPUF) where isocyanate is used in excess of the stoichiometric ratio. In this study, lignin-containing nanocellulose fibrils (LCNF) were explored as mechanical reinforcements for RPUF with the goal of maintaining the mechanical performance of the foam while using less isocyanate. Different amounts of LCNF (0-0.2 wt.%) were added to the RPUF made using isocyanate indices of 1.1, 1.05, 1.0, and 0.95. Results showed that LCNF served as a nucleating agent, significantly reducing cell size and thermal conductivity. LCNF addition increased the crosslinking density of RPUF, leading to enhanced compressive properties at an optimal loading of 0.1 wt.% compared to unreinforced foams at the same isocyanate index. Furthermore, at the optimal loading, LCNF-reinforced foams made at lower isocyanate indices showed comparable stiffness and strength to unreinforced foams made at higher isocyanate indices. These results highlight the reinforcing potential of LCNF in rigid polyurethane foams to improve insulation and mechanical performance with lower isocyanate usage.

14.
Front Pharmacol ; 15: 1394369, 2024.
Article in English | MEDLINE | ID: mdl-39148540

ABSTRACT

Objective: Diabetic nephropathy (DN) is a serious complication that may occur during the later stages of diabetes, and can be further exacerbated by podocyte damage. Piperazine ferulate (PF) has well-defined nephroprotective effects and is used clinically in the treatment of chronic nephritis and other kidney diseases. However, the renoprotective effects and mechanisms of PF on DN are not clear. This study aims to investigate the protective effect of PF on DN and its mechanism of action, to inform the clinical application of PF in DN treatment. Methods: Network pharmacology was performed to predict the mechanism of action of PF in DN. Male Sprague Dawley rats were intraperitoneally injected with STZ (60 mg/kg) to establish a DN model, and then assessed for renal injury after 12 weeks of administration. In vitro, rat podocytes were treated with 25 mmol/L glucose and cultured for 24 h, followed by an assessment of cell injury. Results: Our results showed that PF significantly improved renal function, reduced renal pathological changes, decreased inflammatory response, and alleviated podocyte damage in DN rats. PF also attenuated glucose-induced podocyte injury in vitro. Regarding molecular mechanisms, our study demonstrated that PF downregulated the expression of genes and proteins related to AGE-RAGE-mediated inflammatory signaling. Conclusion: In summary, PF exerts its renoprotective effects by decreasing inflammation and protecting against podocyte injury through the inhibition of the AGE/RAGE/NF-κB/NLRP3 pathway. Overall, these data support the clinical potential of PF as a renoprotective agent in DN.

16.
Catal Sci Technol ; 14(19): 5662-5670, 2024 Sep 30.
Article in English | MEDLINE | ID: mdl-39156760

ABSTRACT

The local coordination environment of single atom catalysts (SACs) often determines their catalytic performance. To understand these metal-support interactions, we prepared Pt SACs on cerium dioxide (CeO2) cubes, octahedra and rods, with well-structured exposed crystal facets. The CeO2 crystals were characterized by SEM, TEM, pXRD, and N2 sorption, confirming the shape-selective synthesis, identical bulk structure, and variations in specific surface area, respectively. EPR, XPS, TEM and XANES measurements showed differences in the oxygen vacancy density following the trend rods > octahedra > cubes. AC-HAADF-STEM, XPS and CO-DRIFTS measurements confirmed the presence of only single Pt2+ sites, with different surface platinum surface concentrations. We then compared the performance of the three catalysts in ammonia borane hydrolysis. Precise monitoring of reaction kinetics between 30-80 °C gave Arrhenius plots with hundreds of data points. All plots showed a clear inflection point, the temperature of which (rods > octahedra > cubes) correlates to the energy barrier of ammonia borane diffusion to the Pt sites. These activity differences reflect variations in the - facet dependent - degree of stabilization of intermediates by surface oxygen lone pairs and surface-metal binding strength. Our results show how choosing the right macroscopic support shape can give control over single atom catalysed reactions on the microscopic scale.

17.
Food Chem ; 460(Pt 3): 140670, 2024 Dec 01.
Article in English | MEDLINE | ID: mdl-39106747

ABSTRACT

Anthocyanins are natural flavonoids with a high antioxidant power and many associated health benefits, but most rice produce little amounts of these compounds. In this study, 141 MYB transcription factors in 15 chromosomes, including the nucleus-localised ZlMYB1 (Zla03G003370) and ZlMYB2 (Zla15G015220), were discovered in Zizania latifolia. Overexpression of ZlMYB1 or ZlMYB2 in rice seeds induced black pericarps, and flavonoid content, antioxidant capacity, and α-glucosidase and tyrosinase inhibition effects significantly increased compared to those in the control seeds. ZlMYB1 and ZlMYB2 overexpression induced the upregulation of 764 and 279 genes, respectively, and the upregulation of 162 and 157 flavonoids, respectively, linked to a black pericarp phenotype. The expression of flavonoid 3'-hydroxylase and UDP-glycose flavonoid glycosyltransferase, as well as the activities of these enzymes, increased significantly in response to ZlMYB1 or ZlMYB2 overexpression. This study systematically confirmed that the overexpression of ZlMYB1 and ZlMYB2 promotes flavonoid biosynthesis (especially of anthocyanins) in rice.


Subject(s)
Antioxidants , Flavonoids , Monophenol Monooxygenase , Oryza , Plant Proteins , Seeds , alpha-Glucosidases , Seeds/chemistry , Seeds/genetics , Seeds/metabolism , Seeds/enzymology , Oryza/genetics , Oryza/chemistry , Oryza/metabolism , Oryza/enzymology , Flavonoids/metabolism , Flavonoids/chemistry , Plant Proteins/genetics , Plant Proteins/metabolism , Plant Proteins/chemistry , alpha-Glucosidases/genetics , alpha-Glucosidases/metabolism , alpha-Glucosidases/chemistry , Antioxidants/metabolism , Antioxidants/chemistry , Monophenol Monooxygenase/metabolism , Monophenol Monooxygenase/genetics , Transcription Factors/genetics , Transcription Factors/metabolism , Transcription Factors/chemistry , Gene Expression Regulation, Plant , Glycoside Hydrolase Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Plants, Genetically Modified/genetics , Plants, Genetically Modified/chemistry , Plants, Genetically Modified/metabolism , Plants, Genetically Modified/enzymology
18.
Plants (Basel) ; 13(14)2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39065524

ABSTRACT

The secretions of the glandular trichomes of tobacco leaves and flowers contain abundant secondary metabolites of different compounds, such as cebradanes, labdanes, and saccharide esters. These secondary metabolites have shown interesting biological properties, such as antimicrobial, insecticidal, and antioxidant activity. In this study, 81 air/sun-cured tobacco germplasms were used as experimental materials. Quantitative and qualitative analyses of the glandular secretion components were conducted using ultra-performance liquid chromatography-quadrupole-time of flight-mass spectrometry (UPLC-Q-TOF MS) and gas chromatography-mass spectrometry (GC-MS). The ethanol extracts of glandular trichomes from tobacco leaves and flowers were evaluated for antifungal activity against the fungus Botrytis cinerea using the mycelial growth rate method. Orthogonal Partial Least Squares (OPLS) analysis was then performed to determine the relationship between the trichome secretion components and their anti-fungal activity. The results showed significant differences among the antifungal activities of the tested ethanol extracts of tobacco glandular trichomes. The inhibition rates of the upper leaves and flower extracts against B. cinerea were significantly higher than those of the middle and lower leaves, and 59 germplasms (73.75% of the tested resources) showed antifungal rates higher than 50%, with four germplasms achieving a 95% antifungal rate at the same fresh weight concentration (10 mg/mL). The OPLS analysis revealed that the antifungal activity was primarily associated with alpha-cembratriene-diol (α-CBT-diol (Peak7)) and beta-cembratriene-diol (ß-CBT-diol (Peak8)), followed by sucrose esters III (SE(III)) and cembratriene-diol oxide. These findings help identify excellent tobacco germplasms for the development and utilization of botanical pesticides against fungi and provide a theoretical reference for the multipurpose utilization of tobacco germplasms.

19.
Nat Commun ; 15(1): 6301, 2024 Jul 26.
Article in English | MEDLINE | ID: mdl-39060252

ABSTRACT

Perovskite oxides show promise for the oxygen evolution reaction. However, numerical chemical compositions remain unexplored due to inefficient trial-and-error methods for material discovery. Here, we develop a transfer learning paradigm incorporating a pre-trained model, ensemble learning, and active learning, enabling the prediction of undiscovered perovskite oxides with enhanced generalizability for this reaction. Screening 16,050 compositions leads to the identification and synthesis of 36 new perovskite oxides, including 13 pure perovskite structures. Pr0.1Sr0.9Co0.5Fe0.5O3 and Pr0.1Sr0.9Co0.5Fe0.3Mn0.2O3 exhibit low overpotentials of 327 mV and 315 mV at 10 mA cm-2, respectively. Electrochemical measurements reveal coexistence of absorbate evolution and lattice oxygen mechanisms for O-O coupling in both materials. Pr0.1Sr0.9Co0.5Fe0.3Mn0.2O3 demonstrates enhanced OH- affinity compared to Pr0.1Sr0.9Co0.5Fe0.5O3, with the emergence of oxo-bridged Mn-Co conjugate facilitating charge redistribution and dynamic reversibility of Olattice/VO, thereby slowing down Co dissolution. This work paves the way for accelerated discovery and development of high-performance perovskite oxide electrocatalysts for this reaction.

20.
Chembiochem ; : e202400458, 2024 Jul 22.
Article in English | MEDLINE | ID: mdl-39037928

ABSTRACT

Asymmetric hydrogenation of alkene moieties is important for the synthesis of chiral molecules, but achieving high stereoselectivity remains a challenge. Biocatalysis using ene-reductases (EReds) offers a viable solution. However, the need for NAD(P)H cofactors limits large-scale applications. Here, we explored an electrochemical alternative for recycling flavin-containing EReds using methyl viologen as a mediator. For this, we built a bio-electrocatalytic setup with an H-type glass reactor cell, proton exchange membrane, and carbon cloth electrode. Experimental results confirm the mediator's electrochemical reduction and enzymatic consumption. Optimization showed increased product concentration at longer reaction times with better reproducibility within 4-6 h. We tested two enzymes, Pentaerythritol Tetranitrate Reductase (PETNR) and the Thermostable Old Yellow Enzyme (TOYE), using different alkene substrates. TOYE showed higher productivity for the reduction of 2-cyclohexen-1-one (1.20 mM h-1), 2-methyl-2-cyclohexen-1-one (1.40 mM h-1) and 2-methyl-2-pentanal (0.40 mM h-1), with enantiomeric excesses ranging from 11% to 99%. PETNR outperformed TOYE in terms of enantioselectivity for the reduction of 2-methyl-2-pentanal (ee 59±7% (S)). Notably, TOYE achieved promising results also in reducing ketoisophorone, a challenging substrate, with similar enantiomeric excess compared to published values using NADH.

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