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1.
Nature ; 629(8014): 1158-1164, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38750355

RESUMO

Plant pattern-recognition receptors perceive microorganism-associated molecular patterns to activate immune signalling1,2. Activation of the pattern-recognition receptor kinase CERK1 is essential for immunity, but tight inhibition of receptor kinases in the absence of pathogen is crucial to prevent autoimmunity3,4. Here we find that the U-box ubiquitin E3 ligase OsCIE1 acts as a molecular brake to inhibit OsCERK1 in rice. During homeostasis, OsCIE1 ubiquitinates OsCERK1, reducing its kinase activity. In the presence of the microorganism-associated molecular pattern chitin, active OsCERK1 phosphorylates OsCIE1 and blocks its E3 ligase activity, thus releasing the brake and promoting immunity. Phosphorylation of a serine within the U-box of OsCIE1 prevents its interaction with E2 ubiquitin-conjugating enzymes and serves as a phosphorylation switch. This phosphorylation site is conserved in E3 ligases from plants to animals. Our work identifies a ligand-released brake that enables dynamic immune regulation.


Assuntos
Oryza , Imunidade Vegetal , Proteínas de Plantas , Ubiquitina , Animais , Quitina/metabolismo , Homeostase , Ligantes , Oryza/enzimologia , Oryza/imunologia , Oryza/metabolismo , Oryza/microbiologia , Fosforilação , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/imunologia , Proteínas de Plantas/metabolismo , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Ubiquitina-Proteína Ligases/química , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Fosfosserina/metabolismo , Sequência Conservada
2.
Small ; : e2401464, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38616766

RESUMO

Organic-inorganic hybrid linear and nonlinear optical (NLO) materials have received increasingly wide spread attention in recent years. Herein, the first hybrid noncentrosymmetric (NCS) borophosphate, (C5H6N)2B2O(HPO4)2 (4PBP), is rationally designed and synthesized by a covalent-linkage strategy. 4-pyridyl-boronic acid (4 PB) is considered as a bifunctional unit, which may effectively improve the optical properties and stability of the resultant material. On the one hand, 4 PB units are covalently linked with PO3(OH) groups via strong B-O-P connections, which significantly enhances the thermal stability of 4PBP (decomposition at 321, vs lower 200 °C of most of hybrid materials). On the other hand, the planar π-conjugated C5H6N units and their uniform layered arrangements represent large structural anisotropy and hyperpolarizability, achieving the largest birefringence (0.156 @ 546 nm) in the reported borophosphates and a second-harmonic generation response (0.7 × KDP). 4PBP also exhibits a wide transparency range (0.27-1.50 µm). This work not only provides a promising birefringent material, but also offers a practical covalent-attachment strategy for the rational design of new high-performance optical materials.

3.
Opt Express ; 32(7): 11665-11672, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571008

RESUMO

We demonstrated a 978 nm laser diode (LD) side-pumped YSGG/Er:YSGG/YSGG composite crystal with a size of Ф 3 mm × 65 mm and continuous-wave (CW) mode. By optimizing resonator length and output mirror transmittance, a maximum output power of 28.02 W is generated, corresponding to slope efficiency of 17.55% and optical-optical efficiency of 12.29%, respectively. The thermal focal lengths are obtained by resonator stability condition. The laser wavelength is centered near 2.8 µm. Moreover, the beam quality factors M x2/M y2 are fitted to be 8.14 and 7.35, respectively. The above results indicate that a high-performance 2.8 µm CW laser can be achieved by LD side-pumped YSGG/Er:YSGG/YSGG composite crystal with excellent heat dissipation ability, which promotes effectively the development and applications of the mid-infrared solid-state lasers.

4.
Cell Commun Signal ; 22(1): 269, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745240

RESUMO

BACKGROUND: The pathway involving PTEN-induced putative kinase 1 (PINK1) and PARKIN plays a crucial role in mitophagy, a process activated by artesunate (ART). We propose that patients with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis exhibit insufficient mitophagy, and ART enhances mitophagy via the PINK1/PARKIN pathway, thereby providing neuroprotection. METHODS: Adult female mice aged 8-10 weeks were selected to create a passive transfer model of anti-NMDAR encephalitis. We conducted behavioral tests on these mice within a set timeframe. Techniques such as immunohistochemistry, immunofluorescence, and western blotting were employed to assess markers including PINK1, PARKIN, LC3B, p62, caspase3, and cleaved caspase3. The TUNEL assay was utilized to detect neuronal apoptosis, while transmission electron microscopy (TEM) was used to examine mitochondrial autophagosomes. Primary hippocampal neurons were cultured, treated, and then analyzed through immunofluorescence for mtDNA, mtROS, TMRM. RESULTS: In comparison to the control group, mitophagy levels in the experimental group were not significantly altered, yet there was a notable increase in apoptotic neurons. Furthermore, markers indicative of mitochondrial leakage and damage were found to be elevated in the experimental group compared to the control group, but these markers showed improvement following ART treatment. ART was effective in activating the PINK1/PARKIN pathway, enhancing mitophagy, and diminishing neuronal apoptosis. Behavioral assessments revealed that ART ameliorated symptoms in mice with anti-NMDAR encephalitis in the passive transfer model (PTM). The knockdown of PINK1 led to a reduction in mitophagy levels, and subsequent ART intervention did not alleviate symptoms in the anti-NMDAR encephalitis PTM mice, indicating that ART's therapeutic efficacy is mediated through the activation of the PINK1/PARKIN pathway. CONCLUSIONS: At the onset of anti-NMDAR encephalitis, mitochondrial damage is observed; however, this damage is mitigated by the activation of mitophagy via the PINK1/PARKIN pathway. This regulatory feedback mechanism facilitates the removal of damaged mitochondria, prevents neuronal apoptosis, and consequently safeguards neural tissue. ART activates the PINK1/PARKIN pathway to enhance mitophagy, thereby exerting neuroprotective effects and may achieve therapeutic goals in treating anti-NMDAR encephalitis.


Assuntos
Encefalite Antirreceptor de N-Metil-D-Aspartato , Artesunato , Modelos Animais de Doenças , Fármacos Neuroprotetores , Proteínas Quinases , Animais , Artesunato/farmacologia , Artesunato/uso terapêutico , Camundongos , Feminino , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Encefalite Antirreceptor de N-Metil-D-Aspartato/patologia , Encefalite Antirreceptor de N-Metil-D-Aspartato/tratamento farmacológico , Proteínas Quinases/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurônios/metabolismo , Microscopia Eletrônica de Transmissão , Mitofagia/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Hipocampo/patologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo
5.
Bioprocess Biosyst Eng ; 47(7): 1095-1105, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38847888

RESUMO

In this research, to provide an optimal growth medium for the production of iturin A, the concentrations of key amino acid precursors were optimized in shake flask cultures using the response surface method. The optimized medium were applied in a biofilm reactor for batch fermentation, resulting in enhanced production of iturin A. On this basis, a step-wise pH control strategy and a combined step-wise pH and temperature control strategy were introduced to further improve the production of iturin A. Finally, the fed-batch fermentation was performed based on combined step-wise pH and temperature control. The titer and productivity of iturin A reached 7.86 ± 0.23 g/L and 65.50 ± 1.92 mg/L/h, respectively, which were 37.65 and 65.20% higher than that before process optimization.


Assuntos
Bacillus , Biofilmes , Reatores Biológicos , Biofilmes/crescimento & desenvolvimento , Bacillus/metabolismo , Bacillus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Meios de Cultura , Fermentação , Temperatura , Peptídeos Cíclicos
6.
J Environ Manage ; 365: 121592, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38963959

RESUMO

Methane, either as natural gas or as a resource obtained from various bioprocesses (e.g., digestion, landfill) can be converted to carbon and hydrogen according to. CH4(g)→C(s)+2H2(g)ΔH298K=74.8kJ/mol. Previous research has stressed the growing importance of substituting the high-temperature Steam Methane Reforming (SMR) by a moderate temperature Catalytic Methane Decomposition (CMD). The carbon formed is moreover of nanotube nature, in high industrial demand. To avoid the use of an inert support for the active catalyst species, e.g., Al2O3 for Fe, leading to a progressive contamination of the catalyst by support debris and coking of the catalyst, the present research investigates the use of carbon nanotubes (CNTs) as Fe-support. Average CH4 conversions of 75-85% are obtained at 700 °C for a continuous operation of 40 h. The produced CNT from the methane conversion can be continuously removed from the catalyst bed by carry-over due to its bulk density difference (∼120 kg/m3) with the catalyst itself (∼1500 kg/m3). CNT properties are fully specified. No thermal regeneration of the catalyst is required. A tentative process layout and economic analysis demonstrate the scalability of the process and the very competitive production costs of H2 and CNT.

7.
Opt Express ; 31(14): 23631-23641, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475443

RESUMO

In this work, we report on investigations of structure, spectroscopic properties and laser performances of, what we believe to be, a novel Er:YGGAG laser crystal. High crystalline quality is proved by an FWHW of XRC of 0.019°. Thermal conductivity of a 30 at.% Er:YGGAG crystal is determined as 4.98 W/(m·K). The refractive index is measured in the range of 400 to 1000 nm and fitting with Sellmeier equation is done. A broad fluorescence emission band is located at 2786∼2819 nm, suggesting that this crystal is favorable to realize tunable and ultrafast laser. Under the pump at 969 nm with a fiber-coupled diode laser, at 400 Hz repetition rate and 600 µs pulse duration, the 30 at.% Er:YGGAG delivered maximum average power of 506 mW with overall optical-to-optical efficiency of 12.4% and slope efficiency of 16.9%. The laser beam quality was characterized by M2 factors of 1.53 and 1.39 in horizontal and vertical directions, respectively.

8.
Opt Express ; 31(22): 36429-36438, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-38017796

RESUMO

We demonstrate the thermal, spectroscopy and laser properties of Ho,Pr doped YAP crystal grown successfully by Cz method. The thermal expansion coefficient, thermal conductivity, absorption and emission spectra of Ho,Pr:YAP crystal are investigated in detail. Additionally, the level lifetimes suggest that Pr3+ is a suitable deactivating ion for Ho:YAP crystal. Particularly, the actual laser performance is optimized by doping active ion Ho with high concentrations and introducing deactivated Pr3+, resulting in decreased laser threshold, increased laser output power and slope efficiency. A 3.01 µm laser with output power of 502 mW, slope efficiency of 6.3% and beam quality factors of 1.42/1.43 is achieved in the Ho,Pr:YAP crystal, as far as we know this is the highest ∼3 µm CW laser power realized in Ho3+ doped oxide crystals.

9.
Neurochem Res ; 48(11): 3349-3362, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37268752

RESUMO

Uncovering mechanisms underlying epileptogenesis aids in preventing further epilepsy progression and to lessen seizure severity and frequency. The purpose of this study is to explore the antiepileptogenic and neuroprotective mechanisms of EGR1 in neuron injuries encountered in epilepsy. Bioinformatics analysis was conducted to identify the key genes related to epilepsy. The mice were rendered epileptic using the kainic acid protocol, followed by measurement of seizure severity, high amplitude and frequency, pathological changes of hippocampal tissues and neuron apoptosis. Furthermore, an in vitro epilepsy model was constructed in the neurons isolated from newborn mice, which was then subjected to loss- and gain-of-function investigations, followed by neuron injury and apoptosis assessment. Interactions among EGR1, METTL3, and VIM were analyzed by a series of mechanistic experiments. In the mouse and cell models of epilepsy, VIM was robustly induced. However, its knockdown reduced hippocampal neuron injury and apoptosis. Meanwhile, VIM knockdown decreased inflammatory response and neuron apoptosis in vivo. Mechanistic investigations indicated that EGR1 transcriptionally activated METTL3, which in turn downregulated VIM expression through m6A modification. EGR1 activated METTL3 and reduced VIM expression, thereby impairing hippocampal neuron injury and apoptosis, preventing epilepsy progression. Taken together, this study demonstrates that EGR1 alleviates neuron injuries in epilepsy by inducing METTL3-mediated inhibition of VIM, which provides clues for the development of novel antiepileptic treatments.


Assuntos
Epilepsia , Camundongos , Animais , Epilepsia/induzido quimicamente , Epilepsia/genética , Epilepsia/metabolismo , Convulsões/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Neurônios/metabolismo , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Anticonvulsivantes/metabolismo , Hipocampo/metabolismo
10.
Nitric Oxide ; 136-137: 12-23, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182786

RESUMO

AIM: Increasing evidence has proposed that mitochondrial abnormalities may be an important factor contributing to the development of heart failure with preserved ejection fraction (HFpEF). Hydrogen sulfide (H2S) has been suggested to play a pivotal role in regulating mitochondrial function. Therefore, the present study was designed to explore the protective effect of H2S on mitochondrial dysfunction in a multifactorial mouse model of HFpEF. METHODS: Wild type, 8-week-old, male C57BL/6J mice or cardiomyocyte specific-Cse (Cystathionine γ-lyase, a major H2S-producing enzyme) knockout mice (CSEcko) were given high-fat diet (HFD) and l-NAME (an inhibitor of constitutive nitric oxide synthases) or standardized chow. After 4 weeks, mice were randomly administered with NaHS (a conventional H2S donor), ZLN005 (a potent transcriptional activator of PGC-1α) or vehicle. After additional 4 weeks, echocardiogram and mitochondrial function were evaluated. Expression of PGC-1α, NRF1 and TFAM in cardiomyocytes was assayed by Western blot. RESULTS: Challenging with HFD and l-NAME in mice not only caused HFpEF but also inhibited the production of endogenous H2S in a time-dependent manner. Meanwhile the expression of PGC-1α and mitochondrial function in cardiomyocytes were impaired. Supplementation with NaHS not only upregulated the expression of PGC-1α, NRF1 and TFAM in cardiomyocytes but also restored mitochondrial function and ultrastructure, conferring an obvious improvement in cardiac diastolic function. In contrast, cardiac deletion of CSE gene aggravated the inhibition of PGC-1α-NRF1-TFAM pathway, mitochondrial abnormalities and diastolic dysfunction. The deleterious effect observed in CSEcko HFpEF mice was partially counteracted by pre-treatment with ZLN005 or supplementation with NaHS. CONCLUSION: Our findings have demonstrated that H2S ameliorates left ventricular diastolic dysfunction by restoring mitochondrial abnormalities via upregulating PGC-1α and its downstream targets NRF1 and TFAM, suggesting the therapeutic potential of H2S supplementation in multifactorial HFpEF.


Assuntos
Insuficiência Cardíaca , Sulfeto de Hidrogênio , Camundongos , Masculino , Animais , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/uso terapêutico , Sulfeto de Hidrogênio/metabolismo , Insuficiência Cardíaca/tratamento farmacológico , NG-Nitroarginina Metil Éster/farmacologia , Volume Sistólico , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Camundongos Knockout , Cistationina gama-Liase/metabolismo
11.
Inorg Chem ; 62(42): 17333-17340, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37823856

RESUMO

Birefringent crystals can modulate and detect the polarization of light and are important optical functional materials. The birefringence is positively correlated to the anisotropy of the structure. By partially substituting sulfate anion with large electronegative fluorine in the parent compound Y2(SO4)3·8H2O, a new fluorinated rare-earth sulfate YSO4F·H2O with enhanced anisotropy was achieved. YSO4F·H2O features a dense 3D structure constructed by the polarizable [YOF] polyhedra and [SO4] tetrahedra. The diffuse reflectance spectrum reveals that it has a short UV absorption edge of below 200 nm. The substitution of the F- ion enhances the optical anisotropy, making the material exhibit an enhanced birefringence (0.0357 at 546 nm), which is 5.1 times that of the parent compound and is also larger than most deep-UV birefringent sulfates. It is expected that this work may shed useful insights in the exploration of deep-UV birefringent materials with enhanced optical performances..

12.
Int J Hyperthermia ; 40(1): 2249274, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37751897

RESUMO

OBJECTIVE: To investigate the factors affecting the efficacy of ultrasound (US)-guided percutaneous microwave ablation (PMWA) for adenomyosis with abnormal uterine bleeding (AUB-A). METHODS: Baseline data of patients with AUB-A who underwent US-guided PMWA treatment between October 2020 and October 2021, including demography characteristics, laboratory and imaging examination results were retrospectively analyzed. 3D reconstruction of magnetic resonance imaging (MRI) was applied to quantitatively assess the local treatment responses, including ratio of non-perfusion volume to adenomyosis volume (NPVr), ablation rate of the endometrial-myometrial junction (EMJ), and surface area (SA) of the ablated part of the EMJ. Patients were followed up at 3, 6, and 12 months after treatment, and divided into two groups: group with complete relief (CR), and group with partial relief (PR) or no relief (NR). Data were compared between them. RESULTS: Thirty-one patients were analyzed with a mean age of 38.7 ± 6.8 years (range: 24-48): 48.4% (15/31), 63.3% (19/30), and 65.5% (19/29) achieved CR at 3, 6, and 12 months, respectively. In univariate analysis, compared with the PR/NR group, serum CA125 levels were significantly lower in CR group at 3 months, while ablation rates of EMJ and SA of the ablated part of the EMJ were significantly higher at the three time points. Other baseline characteristics and NPVr did not differ between the two groups. CONCLUSION: Baseline CA125 and ablation rate of the EMJ and SA of the ablated part of the EMJ are associated with the outcome of AUB-A patients after US-guided PMWA treatment.


Assuntos
Adenomiose , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Adenomiose/complicações , Adenomiose/diagnóstico por imagem , Adenomiose/cirurgia , Micro-Ondas/uso terapêutico , Estudos Retrospectivos , Ultrassonografia de Intervenção , Hemorragia Uterina
13.
J Basic Microbiol ; 63(2): 179-189, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36515292

RESUMO

Bacillus subtilis, as a biocontrol bacterium, possess a variety of biological functions and the capacity to control plant pathogens. Iturin A is a biosurfactant with broad-spectrum antifungal activity produced by fermentation of B. subtilis. In this study, the dynamic parameters of solid-state fermentation (SSF) and submerged fermentation (SMF) of Bacillus velezensis ND were compared, and a method for producing iturin A with a yield of 12.46 g/kg utilizing SSF was proposed. It has significant advantages over SMF and has the highest yield of all previously reported studies. B. velezensis ND also contains protease activity, cellulase activity, iron-carrying activity, the ability to synthesis 3-indoleacetic acid (IAA), fixation nitrogen, and degrade phosphorus. In cotton pot experiments, it can effectively increase cotton growth and minimize Verticillium wilt. This strain's superior fermentation efficiency, biological function, and biocontrol ability are sufficient to demonstrate its promise for the development and use of biocontrol agents.


Assuntos
Bacillus , Agentes de Controle Biológico , Bacillus/metabolismo , Bacillus subtilis/metabolismo , Agentes de Controle Biológico/farmacologia , Agentes de Controle Biológico/metabolismo , Peptídeos Cíclicos
14.
Int J Mol Sci ; 24(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139198

RESUMO

ß-Farnesene is an advanced molecule with promising applications in agriculture, the cosmetics industry, pharmaceuticals, and bioenergy. To supplement the shortcomings of rational design in the development of high-producing ß-farnesene strains, a Metabolic Pathway Design-Fermentation Test-Metabolomic Analysis-Target Mining experimental cycle was designed. In this study, by over-adding 20 different amino acids/nucleobases to induce fluctuations in the production of ß-farnesene, the changes in intracellular metabolites in the ß-farnesene titer-increased group were analyzed using non-targeted metabolomics. Differential metabolites that were detected in each experimental group were selected, and their metabolic pathways were located. Based on these differential metabolites, targeted strain gene editing and culture medium optimization were performed. The overexpression of the coenzyme A synthesis-related gene pantothenate kinase (PanK) and the addition of four mixed water-soluble vitamins in the culture medium increased the ß-farnesene titer in the shake flask to 1054.8 mg/L, a 48.5% increase from the initial strain. In the subsequent fed-batch fermentation, the ß-farnesene titer further reached 24.6 g/L. This work demonstrates the tremendous application value of metabolomics analysis for the development of industrial recombinant strains and the optimization of fermentation conditions.


Assuntos
Sesquiterpenos , Yarrowia , Yarrowia/genética , Fermentação , Sesquiterpenos/metabolismo , Redes e Vias Metabólicas , Engenharia Metabólica
15.
J Environ Manage ; 346: 118999, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37751646

RESUMO

The catalytic CH4 decomposition (CMD) over Fe-based catalyst is an economical and environmentally friendly way to produce Cox-free H2 and carbon nanotubes (CNTs). The Fe-loading was varied to study its influence on the catalytic performance. The highest H2 yield (82.25%) was obtained with a 12% Fe content where the activity of the catalyst did not decrease for 3 h on-stream. A higher Fe content causes the Fe dispersion to decrease, resulting in a reduced available surface area of active sites. Different techniques were used to characterise the fresh and spent catalysts i.e., ICP-AES, XRD, H2-TPR, SEM, TEM, and Raman spectroscopy. Plotting kinetic results as a function of 1/T, defines two different conversion ranges, being reaction rate controlled at low temperature and diffusion rate controlled at high temperature. For the reaction rate controlled regime, the Arrhenius equation provides an activation energy of 101.26 kJ/mol (Ea) and a pre-exponential factor of 393 kmol/s (A).

16.
Appl Microbiol Biotechnol ; 106(8): 2855-2868, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35445856

RESUMO

Poly(ß-L-malic acid) (PMLA) is a water-soluble, biodegradable, and biocompatible polymer with broad prospective applications and can be hydrolyzed to produce widely used acidulant L-malic acid. In order to meet an increasing demand of PMLA, we employed two effective cell-recycling strategies to produce PMLA from raw cassava hydrolysate by Aureobasidium pullulans ZD-3d. In fed-batch fermentation with raw cassava hydrolysate, 101.9 g/L PMLA was obtained with the productivity and yield of 0.77 g/L/h and 0.40 g/g, respectively. Further, three times of membrane filtration-based cell recycling fermentation was carried out, with a high productivity and yield of 1.04-1.64 g/L/h and 0.5-0.84 g/g achieved, respectively. While harnessing centrifugation-based cell recycling fermentation for five times, the productivity and yield approached 0.98-1.76 g/L/h and 0.78-0.86 g/g, respectively. To our knowledge, the processes showed the highest average PMLA productivity compared with others using low-cost biomass, which offered efficient and economical alternatives for PMLA production. KEY POINTS: • PMLA production from raw cassava hydrolysate by Aureobasidium pullulans was studied • High PMLA productivity and yield were obtained via two cell recycling strategies • The highest average PMLA productivity from low-cost biomass to date was achieved.


Assuntos
Manihot , Aureobasidium , Fermentação , Malatos/metabolismo , Manihot/metabolismo
17.
Acta Biochim Biophys Sin (Shanghai) ; 54(1): 55-63, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35130626

RESUMO

Previous studies have reported that the -methyladenosine demethylase ALKBH5 can regulate adipogenesis in humans. However, its function in birds remains unclear. In this study we aimed to explore the expression and function of the gene in chicken adipose tissue. The results showed that is widely expressed in various chicken tissues, and the expression of is relatively higher in abdominal adipose tissue. In addition, the expression of in abdominal adipose tissue of lean broilers is higher than that in fat broilers at 2 and 3 weeks of age. Moreover, the proliferation and differentiation of preadipocytes are associated with reduced and increased expression of , respectively. We also found that knockout promotes preadipocyte proliferation, as evidenced by an increase in cell viability, DNA replication activity, G-S cell cycle progression, and the expressions of and . Furthermore, after knockout of , the lipid droplet accumulation and the expression of , , and are reduced significantly. Thus, our results indicated that ALKBH5 is a novel regulator of proliferation and differentiation of chicken preadipocytes.


Assuntos
Adipócitos , Galinhas , Adenosina/análogos & derivados , Adipócitos/metabolismo , Adipogenia/genética , Animais , Diferenciação Celular/genética , Proliferação de Células/genética
18.
J Environ Manage ; 306: 114429, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35007791

RESUMO

Ambient pressure hydro-deoxygenation (HDO) of the phenolic-rich pyrolysis liquid fraction is a complex task due to the presence multiple phenolic compounds and light oxygenates. The phenolic-rich fraction differs from the overall pyrolysis liquid, known to be prone to re-polymerization and coking in the reactor or of the catalyst. In the present research, hydro-deoxygenation of oxygen-containing compounds in the phenolic fraction over Mo-based catalysts was carried out for the first time. It was found that Mo-based catalysts can successfully upgrade the phenolics into aromatics, the conversion rate was nearly 100%. The small amount of light oxygenates in the phenolic-rich fraction had no obvious effect on the hydro-deoxygenation reaction, the phenolic conversion was more than 95%. After assessing the performance for a representative phenolic model compound, the reaction was also successfully carried out on the phenolic fraction of the real pyrolysis liquid. It can be concluded that the catalysts can also be used for the HDO of the real pyrolysis liquid fraction at atmospheric pressure.


Assuntos
Coque , Pirólise , Pressão Atmosférica , Biomassa , Catálise , Temperatura Alta , Fenóis
19.
J Environ Manage ; 317: 115427, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35653846

RESUMO

Adsorption is a widely applied waste water treatment technology, especially for removing micro-pollutants and dyes of industrial effluents. Over the past decade, adsorbing metal oxide micron- and nano-particles have been successfully developed and investigated as adsorbents. In the present research, Mg-ferrite adsorbent particles were synthesized and their properties were fully determined. The pore volume is 0.139 cm3/g. The BET analysis reveals a surface area of 94.4 m2/g. The porosity is of meso- and microporous nature. The adsorbent was used to adsorb acid fuchsine, an important industrial dye. The equilibrium adsorption capacity was 796.4 mg/g, with an adsorption yield of 78.7-82.0%. The adsorption kinetics can be adequately fitted by a pseudo-second-order model. The isotherms of both Langmuir and Freundlich are applicable. The stability, recovery and reuse of the ferrite particles were proven in multi-cycle experiments, and the adsorption activity decreased by less than 3% between the first and fifth cycle. Experimental and fitting results were finally used to design a batch adsorber to remove a given concentration of acid fuchsine from different volumes of wastewater.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Corantes , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Águas Residuárias , Purificação da Água/métodos
20.
J Environ Manage ; 321: 116019, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36029634

RESUMO

Current energy systems have a significant environmental impact and contribute to the climate change. The future energy systems must call upon clean and renewable sources, capable of producing energy with low CO2 emission, hence partly decarbonizing the energy sector. Producing H2 by catalytic steam reforming of methanol (CSRM) is gaining interest for its specific applications in fuel cells, in a decentralized H2 production, or to locally boost the heat content of e.g. natural gas. Supported metal catalysts enhance the endothermic steam-driven methanol conversion. The paper discusses the CSRM manufactures and assesses 2 novel, cheap and efficient catalysts (Co/α-Al2O3 and MnFe2O4). The performance of the Co/α-Al2O3 catalyst is significantly superior to MnFe2O4. The methanol conversion exceeds 95% with high H2 yields (>2.5 mol H2/mol CH3OH) and low CO and CO2 by-product formation. The methanol reaction is very fast and a nearly constant product distribution is achieved for gas-catalyst contact times in excess of 0.3 s. The catalyst maintains its efficiency and selectivity for several days of reaction. The hydrogen productivity of the Co/α-Al2O3 is about 0.9 L H2 gcat-1 h-1., nearly a fourfold of the MnFe2O4 alternative. The different occurring reactions are combined in a kinetics analysis and demonstrate the high rate of reaction and the predicted product distribution. A catalytic sintered metal fleece reactor is finally developed, mostly in view of its integration with a solid oxide fuel cell (SOFC). The assessed CSRM system clearly merits further pilot plant research.


Assuntos
Hidrogênio , Vapor , Dióxido de Carbono , Catálise , Metais , Metanol
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