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1.
Molecules ; 29(8)2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38675516

RESUMO

Recently, composite materials consisting of ionic liquids (ILs) and metal-organic frameworks (MOFs) have attracted a great deal of attention due to their fantastic properties. Many theoretical studies have been performed on their special structures and gas separation applications. Yet, the mechanism for the diffusion of ILs inside MOF channels still remains unclear. Here, the DFT calculations (e.g., rigid and relaxed potential energy surface, PES, scan) together with frontier orbital analysis, natural charge analysis, and energy decomposition analysis were performed to investigate the diffusion behavior of a typical IL, [C4mim][PF6], into the ZIF-8 SOD cage. The PES profiles indicate that it is quite difficult for the cation [C4min]+ to diffuse into the cage of ZIF-8 through the pristine pores because of the large imidazole steric hindrance, which results in a large energy barrier of ca. 40 kcal·mol-1 at the least. Interestingly, the PES reveals that a successful diffusion could be obtained by thermal contributions, which enlarge the pore size through swing effects at higher temperatures. For example, both [C4mim]+ and [PF6]- could easily diffuse through the channel of the ZIF-8 SOD cage when the pore size was increased to 6.9 Å. Subsequently, electronic structure analyses reveal that the main interactions between [PF6]- or [C4mim]+ and ZIF-8 are the steric repulsion interactions. Finally, the effects of the amounts of [C4mim][PF6] on the ZIF-8 structures were investigated, and the results show that two pairs of [C4mim][PF6] per SOD cage are the most stable in terms of the interaction between energies and structural changes. With these findings, we propose that the high-temperature technique could be employed during the synthesis of IL@MOF membranes, to enrich their family members and their industrial applications.

2.
Biotechnol Appl Biochem ; 70(1): 210-220, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35398919

RESUMO

Recently, composting cultivation method is widely used in oyster mushroom production. In this study, we focused on the effects of composting processes on nutritional qualities and antioxidant activity of Pleurotus floridanus mushroom fruiting bodies. Three treatments of different composting time (2, 4, and 5 days) were performed with an atmospheric sterilization treatment as the control. The results showed that the pH value, total carbon content, and total nitrogen content of substrate were critical parameters which would significantly affect mushroom qualities and bioactivities. Fruiting bodies of the control demonstrated significantly higher crude protein content, total amino acid content, and essential amino acid content than that of composting treatments. Moreover, fruiting bodies of treatment D4 and D5 manifested significantly higher crude polysaccharide contents. Crude polysaccharide of treatment D4 represented the highest scavenging ability toward both radical 3-ethylbenzthiazoline-6-sulfonic acid (ABTS·+ ) and Hydroxyl radical (OH·). It suggests that composting processes is suitable for oyster mushroom cultivation based on nutritional and antioxidant qualities of fruiting bodies.


Assuntos
Compostagem , Pleurotus , Prunus persica , Antioxidantes/química , Pleurotus/metabolismo
3.
Angew Chem Int Ed Engl ; 59(49): 22080-22085, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786102

RESUMO

A bifunctional catalyst comprising CuCl2 /Al2 O3 and nitrogen-doped carbon was developed for an efficient one-pot ethylene oxychlorination process to produce vinyl chloride monomer (VCM) up to 76 % yield at 250 °C and under ambient pressure, which is higher than the conventional industrial two-step process (≈50 %) in a single pass. In the second bed, active sites containing N-functional groups on the metal-free N-doped carbon catalyzed both ethylene oxychlorination and ethylene dichloride (EDC) dehydrochlorination under the mild conditions. Benefitting from the bifunctionality of the N-doped carbon, VCM formation was intensified by the surface Cl*-looping of EDC dehydrochlorination and ethylene oxychlorination. Both reactions were enhanced by in situ consumption of surface Cl* by oxychlorination, in which Cl* was generated by EDC dehydrochlorination. This work offers a promising alternative pathway to VCM production via ethylene oxychlorination at mild conditions through a single pass reactor.

4.
BMC Health Serv Res ; 19(1): 955, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31829178

RESUMO

BACKGROUND: For rabies prevention and treatment, the Chinese government has been establishing standardized rabies clinics since 2016. This study aimed to investigate the distribution of rabies clinics and the achievements of newly-implemented standardized rabies clinics in mainland China, for the purpose of providing further rabies control strategies. METHODS: The number of rabies clinics, including per million inhabitants in each region, was determined. We sampled 1200 clinics from 8 provinces by multi-stage stratified sampling, and a questionnaire survey was carried out to record each clinic's achievements. Data collected from 1185 questionnaires were analyzed. RESULTS: We found that rabies clinics were mostly located in the southwest, central, and eastern regions of China; these accounted for 67.1% of all clinics. The eastern and south regions showed the lowest number of rabies clinics per million inhabitants (0.15 and 0.12, respectively). The total standard-reaching rate of rabies clinics in mainland China was only 11.0%, with significant differences in the rate among regions (X2 = 33.004, p <  0.001). Specifically, the qualified rates of supporting facilities and functional areas were 13.9% (X2 = 34.003, p <  0.001) and 56.1% (X2 = 9.943, p = 0.019), respectively. Vaccines with 2 different substrates and professional flushing equipment were provided by 40.5% (X2 = 27.935, p = 0.001) and 37.7% (X2 = 54.922, p = 0.001) of clinics, respectively. CONCLUSION: Regional differences do exist in the distribution of rabies clinics in mainland China, with relative low number per million population in south and eastern China. There are few standardized rabies clinics in mainland China. Efforts are needed to establish supporting facilities, especially for wound treatment and vaccination. Future research should focus on the improvement of rabies clinics standardization.


Assuntos
Instalações de Saúde/estatística & dados numéricos , Raiva/prevenção & controle , China/epidemiologia , Pesquisa sobre Serviços de Saúde , Humanos
5.
Phys Chem Chem Phys ; 19(19): 12246-12254, 2017 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-28451667

RESUMO

Potassium (K), an important impurity in syngas from biomass, can have a large influence on the activity and selectivity of cobalt-based Fischer-Tropsch synthesis (FTS) catalysts in Biomass to Liquids (BTL) processes. In this work, the potassium adsorption behavior on hcp cobalt was systematically studied using density functional theory. The surface energy calculations and Wulff construction of the equilibrium shape of hcp cobalt showed it is dominated by 10 facets. The interaction of K with these facets has been investigated. The results showed that the stepped facet (10-12) has the highest K adsorption energy of -2.40 eV. The facets (0001), (10-10), (10-11), (10-15), and (21-30) also showed relatively high K adsorption energies in the range of -2.28 to -2.34 eV. The corrugated facets exhibited comparatively lower K adsorption energies (-2.04 to -2.18 eV), and would be less favorable for K adsorption. It was also found that the adsorption properties depend on coverage, where the K adsorption energy decreased with increasing coverage. Diffusion energy barrier calculations indicated that K was mobile on typical facets (0001) and (10-11) with very low diffusion barriers (<0.15 eV). On stepped facets, although K could move freely along the same step (diffusion barrier <0.01 eV), diffusion from one step to another had a significantly higher barrier of 0.56 eV. This suggested that K atoms would be mobile to some extent during FTS reaction conditions, and tend to occupy the most favorable sites independent of their initial position. The results obtained in this work provide valuable information on the interaction of K with cobalt surfaces, relevant for practical cobalt catalysts and their application in BTL processes.


Assuntos
Cobalto/química , Modelos Químicos , Potássio/química , Adsorção , Biomassa , Catálise , Termodinâmica
6.
Adv Sci (Weinh) ; 11(24): e2309865, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38634577

RESUMO

Copper-based bimetallic heterojunction catalysts facilitate the deep electrochemical reduction of CO2 (eCO2RR) to produce high-value-added organic compounds, which hold significant promise. Understanding the influence of copper interactions with other metals on the adsorption strength of various intermediates is crucial as it directly impacts the reaction selectivity. In this review, an overview of the formation mechanism of various catalytic products in eCO2RR is provided and highlight the uniqueness of copper-based catalysts. By considering the different metals' adsorption tendencies toward various reaction intermediates, metals are classified, including copper, into four categories. The significance and advantages of constructing bimetallic heterojunction catalysts are then discussed and delve into the research findings and current development status of different types of copper-based bimetallic heterojunction catalysts. Finally, insights are offered into the design strategies for future high-performance electrocatalysts, aiming to contribute to the development of eCO2RR to multi-carbon fuels with high selectivity.

7.
Life (Basel) ; 14(2)2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38398710

RESUMO

In recent years, short-term composting techniques have been widely applied in oyster mushroom cultivation, but there is still a lack of systematic research on their impact on the nutritional and functional properties of fruiting bodies. In this study, the microbial inoculant Streptomyces thermoviolaceus BUA-FM01 (ST) was applied in the short-term composting process for oyster mushroom cultivation. The agronomic traits, nutritional composition, flavor compounds, and antioxidant activity of fruiting bodies from the first three flushes were evaluated. The results show that microbial inoculation significantly (p < 0.05) reduced the total carbon content and C/N ratio of the composted substrates and, furthermore, increased the total yield of the fruiting bodies. Moreover, microbial inoculation significantly (p < 0.05) increased the crude protein, crude polysaccharide, total amino acid, and essential amino acid contents of the fruiting bodies. The fruiting bodies of the first flush of ST treatment possessed the highest umami amino acid content and equivalent umami concentration value. Furthermore, microbial inoculation significantly (p < 0.05) enhanced the scavenging ability of crude polysaccharides toward free radicals. The results indicate that microbial inoculation has many benefits for the composting cultivating process of oyster mushrooms and good application prospects.

8.
J Basic Microbiol ; 53(10): 868-75, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23322529

RESUMO

A monomeric acid phosphatase (ACP) with a molecular mass of 72.5 kDa was purified from fresh fruiting bodies of cultured Schizophyllum commune mushroom. The isolation procedure entailed ion exchange chromatography on DEAE-cellulose, CM-cellulose, and Q-sepharose, and gel filtration by fast protein liquid chromatography on Superdex 75. It demonstrated a unique N-terminal amino acid sequence of NAPWAQIDEV, which exhibited 60% amino acid identity to that of S. commune hypothetical histidine ACP based on its genome sequence, but less than 30% amino acid identity to that of other fungal ACPs previously reported. The ACP exhibited an optimum temperature at 50 °C, an optimum pH at pH 4.6, and was considerably stable at a pH range of 4.0 to 9.0, and a temperature range of 20-40 °C. The Km of the purified enzyme for ρ-nitrophenyl phosphate (ρNPP) was 0.248 mM and the Vmax was 9.093 × 10(-3) µM/min. ACP activity was strongly inhibited by Al(3+) and Fe(3+) , but enhanced by Co(2+) , Mg(2+) , and Ca(2+) at a concentration of 0.5 mM.


Assuntos
Fosfatase Ácida/isolamento & purificação , Fosfatase Ácida/metabolismo , Carpóforos/enzimologia , Schizophyllum/enzimologia , Fosfatase Ácida/química , Sequência de Aminoácidos , Cromatografia em Gel , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Estabilidade Enzimática , Carpóforos/fisiologia , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Peso Molecular , Especificidade por Substrato , Temperatura
9.
Indian J Biochem Biophys ; 50(3): 196-201, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23898482

RESUMO

A 15 kDa ribonuclease (RNase) was purified from dried fruiting bodies of the wild edible mushroom Armillaria luteo-virens. The simple 4-step purification protocol involved ion-exchange chromatography on DEAE-cellulose, affinity chromatography on Affi-gel blue gel, ion-exchange chromatography on SP-Sepharose and a final gel filtration by FPLC on Superdex-75. The RNase was unadsorbed on Affi-gel blue gel, but adsorbed on DEAE-cellulose and SP-Sepharose. The N-terminal amino acid sequence of purified RNase was AGVQYKLTILLV, which showed low sequence homology to those of previously reported RNases. The optimal pH and temperature of the enzyme were very close to 4.0 and 70 degrees C, respectively. The enzyme showed considerably high ribonucleolytic activity and broad specificity towards polyhomoribonucleotides, with a specificity of poly(U) > poly(C) > poly (G) > poly(A). The ribonucleolytic activities towards poly(U), poly(C), poly(G) and poly(A) were 279.5, 184.1, 69.9 and 52.3 U/mg, respectively.


Assuntos
Agaricales/enzimologia , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Ribonucleases/química , Ribonucleases/isolamento & purificação , Animais , Ativação Enzimática , Estabilidade Enzimática , Especificidade por Substrato
10.
Sci Total Environ ; 905: 167399, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37793443

RESUMO

Hexavalent chromium (Cr(VI)) is carcinogenic and widely presented in soil. In this study, modified zero-valent iron (ZVI) with oxalic acid on biochar (OA-ZVI/BC) was prepared using wet ball milling method for the remediation of Cr(VI)-contaminated soil. Microscopic characterizations showed that ZVI were distributed on the biochar uniformly and confirmed the enhanced interface interaction between biochar and ZVI by wet ball milling. Electrochemical analysis indicated the strong electron transfer ability and enhanced corrosion behavior of OA-ZVI/BC. Moreover, inhibitory efficiencies of Cr(VI) removal with the addition of 1,10-phenanthroline suggested abundant Fe2+ generation in OA-ZVI/BC, which might facilitate the reduction of Cr(VI) to Cr(III). Theory calculation further demonstrated the ZVI modified by oxalic acid was more susceptible to solid-solid interfacial reactions with Cr(VI), and more electrons were transferred to Cr(VI). When applied to Cr(VI)-contaminated soil, OA-ZVI/BC could passivate 96.7 % total Cr(VI) and maintained for 90 days. The toxicity characteristic leaching procedure (TCLP) and simple based extraction test (SBET) were used to evaluate the leaching toxicity and bioaccessibility of Cr(VI), respectively. The TCLP-Cr(VI) decreased to 0.11 mg·L-1 after OA-ZVI/BC treatment, much lower than that of soils with ZVI/BC and OA-ZVI remediation (1.5 mg·L-1 and 4.1 mg·L-1). The bioaccessibility of Cr(VI) reduced by 93.5 % after 3-month remediation. Sequential extraction showed that Cr fractions in the soil after OA-ZVI/BC remediation was converted from acetic acid-extractable (HOAc-extractable) to more stable forms (e.g., residual and oxidizable forms). Benefiting from the synergies of oxalic acid, biochar and wet ball milling, OA-ZVI/BC exhibited an excellent performance on the remediation of Cr(VI)-contaminated soil, whose mechanisms involved adsorption, reduction (Fe0/Fe2+, Fe2+/Fe3+) and co-precipitation. This study herein develops a promising ZVI technology in the remediation of heavy metal-contaminated soil.

11.
Front Microbiol ; 14: 1218205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37476665

RESUMO

Spent mushroom substrate (SMS) is the by-products of mushroom production, which is mainly composed of disintegrated lignocellulosic biomass, mushroom mycelia and some minerals. The huge output and the lack of effective utilization methods make SMS becoming a serious environmental problem. In order to improve the application of SMS and SMS derived biochar (SBC), composted SMS (CSMS), SBC, combined plant growth-promoting rhizobacteria (PGPR, Bacillus subtilis BUABN-01 and Arthrobacter pascens BUAYN-122) and SBC immobilized PGPR (BCP) were applied in the lettuce seedling. Seven substrate treatments were used, including (1) CK, commercial control; (2) T1, CSMS based blank control; (3) T2, T1 with combined PGPR (9:1, v/v); (4) T3, T1 with SBC (19:1, v/v); (5) T4, T1 with SBC (9:1, v/v); (6) T5, T1 with BCP (19:1, v/v); (7) T6, T1 with BCP (9:1, v/v). The physicochemical properties of substrate, agronomic and physicochemical properties of lettuce and rhizospheric bacterial and fungal communities were investigated. The addition of SBC and BCP significantly (p < 0.05) improved the total nitrogen and available potassium content. The 5% (v/v) BCP addiction treatment (T5) represented the highest fresh weight of aboveground and underground, leave number, chlorophyll content and leaf anthocyanin content, and the lowest root malondialdehyde content. Moreover, high throughput sequencing revealed that the biochar immobilization enhanced the adaptability of PGPR. The addition of PGPR, SBC and BCP significantly enriched the unique bacterial biomarkers. The co-occurrence network analysis revealed that 5% BCP greatly increased the network complexity of rhizospheric microorganisms and improved the correlations of the two PGPR with other microorganisms. Furthermore, microbial functional prediction indicated that BCP enhanced the nutrient transport of rhizospheric microorganisms. This study showed the BCP can increase the agronomic properties of lettuce and improve the rhizospheric microbial community.

12.
Front Microbiol ; 14: 1274032, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38282740

RESUMO

Introduction: Broken eggs are a byproduct of the poultry industry and a potential nitrogen source for mushroom cultivation. However, its feasibility needs to be evaluated experimentally. Methods: In this study, a series of different addition amounts (0, 1.8, 3.6, 5.3 and 8.5%, w/w) of broken egg mixture (BEM) were applied in the composting cultivation process of oyster mushroom. The physicochemical properties and bacterial communities of composting substrate, and agronomic and nutritional properties of fruiting bodies were determined. Results and discussion: The results showed that the BEM addition significantly (P < 0.05) increased the total nitrogen content in the composted substrate, and the contents of crude protein, total amino acids and essential amino acids of mushrooms. The P3 treatment (initial C/N of 26:1) showed the highest biological efficiency (BE) of 100.19% and a low contamination rate (CR) of 7.00%, while the higher dosage of BEM (P4 and P5) led to a sharp decrease in BE and a sharp increase in CR. High throughput sequencing revealed that the addition of BEM significantly (P < 0.05) changed the bacterial communities in the substrate at the beginning of composting. Streptococcus and Lactococcus were predominant bacterial genera in BEM treatments at the beginning stage of composting, while Acinetobacter became predominant at the ending stage. The co-occurrence network analysis showed that the P3 treatment demonstrated a much more complex bacterial community. The structural equation model analysis indicated that the addition of BEM affected the bacterial communities and nitrogen metabolism during composting, which further affected agronomic and nutritional properties of oyster mushrooms. An appropriate amount of BEM combined with composting processes can significantly improve the yield and quality of oyster mushroom, providing a new way for efficient utilization of BEM.

13.
J Biomed Biotechnol ; 2012: 736472, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23093860

RESUMO

A novel 68 kDa laccase was purified from the mycorrhizal fungus Agaricus placomyces by utilizing a procedure that comprised three successive steps of ion exchange chromatography and gel filtration as the final step. The monomeric enzyme exhibited the N-terminal amino acid sequence of DVIGPQAQVTLANQD, which showed only a low extent of homology to sequences of other fungal laccases. The optimal temperature for A. placomyces laccase was 30°C, and optimal pH values for laccase activity towards the substrates 2,7'-azinobis[3-ethylbenzothiazolone-6-sulfonic acid] diammonium salt (ABTS) and hydroquinone were 5.2 and 6.8, respectively. The laccase displayed, at 30°C and pH 5.2, K(m) values of 0.392 mM towards hydroquinone and 0.775 mM towards ABTS. It potently suppressed proliferation of MCF 7 human breast cancer cells and Hep G2 hepatoma cells and inhibited human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) activity with an IC(50) of 1.8 µM, 1.7 µM, and 1.25 µM, respectively, signifying that it is an antipathogenic protein.


Assuntos
Agaricus/enzimologia , Transcriptase Reversa do HIV/antagonistas & inibidores , Lacase/administração & dosagem , Lacase/metabolismo , Neoplasias Experimentais/tratamento farmacológico , Inibidores da Transcriptase Reversa/química , Proliferação de Células/efeitos dos fármacos , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/farmacologia , Células Hep G2 , Humanos , Células MCF-7 , Neoplasias Experimentais/patologia
14.
ACS Omega ; 7(45): 40807-40814, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36406518

RESUMO

Development of efficient hydrogen storage materials is one of the great challenges in the area of hydrogen energy and fuel cells. Herein, a La-doped Ti1.2CrMn alloy with high hydriding capacity (2.1 wt % H) and dehydriding capacity (1.8 wt % H) was successfully developed. The crystallographic characteristics, microstructural evolution, and hydrogen storage mechanisms of the alloy were investigated systematically. It was found that the introduction of La increased the cell volume of alloy and thus improved the hydrogenation kinetic, practical hydrogenation capacity, and cyclic property. The hydrogenation kinetic results of the La-doped alloy indicate that it exhibited a higher hydrogenation rate than that of the La-free alloy. It is ascribed to the formation of LaH3, which provides a fast diffusion channel for hydrogen atoms to enter the alloy matrix. The dehydrogenation enthalpy (ΔH) of the La-doped alloy was calculated by the van't Hoff equation and PCT curves to be ∼18.2 kJ/mol. The cycle test proves that the La-doped Ti1.2CrMn alloy, due to La addition, reduces the lattice expansion and lattice stress and exhibits excellent durability.

15.
Sci Total Environ ; 847: 157673, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35905953

RESUMO

A short-term composting process to prepare substrate is an effective way to cultivate oyster mushrooms (Pleurotus spp.), which can increase the yield of mushrooms and lower the rate of contamination in non-industrialized cultivation. Moreover, it is different from the traditional composting processes for fertilizers and lacks systematic study, such as microbial succession and compost quality. In this study, a series of different tests of composting duration (0, 2, 4 and 5 d) were performed. A composting duration of 4-5 d over 58 °C was suitable for mushroom cultivation based on the biological efficiency (BE) range of 69.76-73.41 % and the contamination rate of 0 %. The content of total carbon (TC) continuously decreased during composting, while the content of total nitrogen (TN) reacted in an opposite matter. The final TN and C/N ratios were 1.89 % and 28/1, respectively, which fell well within the optimal range of nutritional requirements for oyster mushroom cultivation. The composting bacteria were more diverse than the fungal species. Caldibacillus, Thermobispora, Thermopolyspora, Thermobacillus and Ureibacillus were the predominant bacterial genera during the thermophilic stage. Co-occurrence patterns of microbial communities and physicochemical properties were performed using a network analysis, which indicated that bacteria can play more efficient roles than fungi in the degradation of organic matter. The structural equation model showed that composting duration significantly affected bacterial diversity, lignocellulose degradation rates, and BE. The correlations between bioinformatics parameters with composting characters and agronomic traits were determined by the Mantel test and showed that the induction of bacterial diversity over time rapidly activated carbon metabolism during short-term composting. This study provides a new idea of agro-waste composting for mushroom cultivation.


Assuntos
Agaricales , Compostagem , Microbiota , Pleurotus , Bactérias/metabolismo , Carvão Vegetal/metabolismo , Fertilizantes/análise , Nitrogênio/análise , Pleurotus/metabolismo
16.
ACS Appl Mater Interfaces ; 13(39): 47163-47173, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34555902

RESUMO

Solid polymer electrolytes (SPEs) of superior ionic conductivity, long-term cycling stability, and good interface compatibility are regarded as promising candidates to enable the practical applications of solid lithium metal batteries (SLMBs). Here, a mixed-matrix SPE (MMSE) with incorporated metal-organic frameworks (MOFs) and ionic liquid is prepared. The dissociation of Li salt in MMSE can be promoted effectively due to the introduction of MOF via the Fourier-transform infrared spectroscopy (FT-IR) analysis, density functional theory calculation, and molecular dynamics simulation. The as-formed MMSE exhibits an ultralow thickness of 20 µm with a satisfactory ionic conductivity and lithium-ion transference number (1.1 mS cm-1 at 30 °C, 0.72). The optimized SLMBs with high-voltage LiMn0.75Fe0.25PO4 (LMFP) exhibit an excellent cyclability at 4.2 V under room temperature. Moreover, Li/MMSE/LiFePO4 cells have desirable cycle performance from -20 to 100 °C, and their capacity remains 143.3 mA h g-1 after being cycled 300 times at 10 C at 100 °C. The Li/LiFePO4 pouch cells also show excellent safety under extreme conditions. The Li symmetric cells can work steadily even at a supreme current density of 4 mA cm-2 at 100 °C. From the above analysis, these MMSEs present new opportunities for the development of SLMBs with good electrochemical properties.

17.
Food Sci Nutr ; 9(4): 1860-1869, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33841805

RESUMO

Limonin is an important bioactive substance in citrus fruits, especially in seeds, which has great potential in cancer prevention and treatment. In order to explore the anticancer activity based on interaction between limonin and NQO1, Human promyelocytic leukemia cells (HL-60) were studied in vitro. We found that limonin could inhibit proliferation and promote apoptosis of HL-60 cells, and the effect was positively correlated with its dosage. Western blot results showed that limonin could activate the endogenous apoptosis pathway mediated by mitochondria via up-regulating pro-apoptotic proteins (Bax, cytochrome c, Caspase3, and Caspase9) and down-regulating anti-apoptotic proteins (Bcl-2), thus inhibiting the proliferation of HL-60 cells and promoting apoptosis, which further proved the anticancer activity of limonin from the molecular mechanism. At the same time, limonin down-regulated the expression of NQO1, indicating that limonin may indirectly act on the apoptosis pathway by regulating the expression activity of antioxidant enzymes in vivo, thus exerting its inhibitory effect on tumor cells, which provides an idea for the molecular mechanism that natural products can indirectly exert their anticancer effect by regulating the activity of antioxidant enzymes.

18.
Front Microbiol ; 12: 672620, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34413835

RESUMO

An extracellular laccase (GLL) was purified from fermentation broth of the litter-decomposing fungus Gymnopus luxurians by four chromatography steps, which resulted in a high specific activity of 118.82 U/mg, purification fold of 41.22, and recovery rate of 42.05%. It is a monomeric protein with a molecular weight of 64 kDa and N-terminal amino acid sequence of AIGPV TDLHI, suggesting that GLL is a typical fungal laccase. GLL demonstrated an optimum temperature range of 55°C-65°C and an optimum pH 2.2 toward 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). It displayed considerably high thermostability and pH stability with about 63% activity retained after 24 h at 50°C, and 86% activity retained after 24 h at pH 2.2, respectively. GLL was significantly enhanced in the presence of K+, Na+, and Mg2+ ions. It demonstrated K m of 539 µM and k cat /K m of 140 mM-1⋅s-1 toward ABTS at pH 2.2 and 37°C. Acetosyringone (AS) and syringaldehyde (SA) were the optimal mediators of GLL (0.4 U/ml) for dye decolorization with decolorization rates of about 60%-90% toward 11 of the 14 synthetic dyes. The optimum reaction conditions were determined to be mediator concentration of 0.1 mM, temperature range of 25°C -60°C, and pH 4.0. The purified laccase was the first laccase isolated from genus Gymnopus with high thermostability, pH stability, and effective decolorization toward dyes, suggesting that it has potentials for textile and environmental applications.

19.
Bioresour Technol ; 332: 125079, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33813177

RESUMO

Short-term composting of raw materials for preparing oyster mushroom cultivation media is widely used in China, and its microbial mechanism needs to be further studied. 11-days' peach sawdust-based composting was performed to evaluate material conversion and microbial succession using physicochemical analysis and 16S rRNA and ITS sequencing. Composting bacteria demonstrated much higher abundance than fungi. Firmicutes, Actinobacteriota, and Proteobacteria were the dominant bacterial phyla, while most of fungal species belonged to Ascomycota. Moisture was the key factor at the beginning, while total nitrogen, temperature, and lignin became main influencing factors for composting maturity. Actinobacteriota, Firmicutes, and Proteobacteria of bacterial phyla, Eurotiomycetes and Sordariomycetes of fungal classes involved in lignocellulosic degradation. Bacterial function prediction analysis showed that carbohydrate metabolism and amino acid metabolism were the main metabolic pathways. These results confer a better understanding of material and microbial succession during short-term composting and also provide valuable utilization in mushroom industry.


Assuntos
Compostagem , Microbiota , Prunus persica , China , Esterco , RNA Ribossômico 16S/genética , Solo
20.
Materials (Basel) ; 13(17)2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32872137

RESUMO

To investigate the durability of reinforced concrete (RC) beams under the combined actions of transverse cracks and corrosion, corrosion tests were conducted on a total of eight RC beams with different water-cement ratios and cracking states. The effects of the transverse crack width, water-cement ratio, and the length of the wetting-drying cycle on the distribution of the free chloride concentration, the cross-sectional loss of the tensile steel bars, and the chloride diffusion coefficient are analyzed. The results show that the widths of the transverse crack and the water-cement ratio of concrete greatly affected the chloride profile and content of the RC beam specimens. Specifically, the chloride contents in all the cracked RC beams at the depth of the steel bar exceeded the threshold value of 0.15%. As the width of the cracks increased, the chloride concentration and penetration of the cracked concrete beam increased. However, the chloride concentration at the reinforcement position did not seem to be obviously affected by increasing the wetting-drying cycles from 182 days to 364 days. Moreover, the decrease of the water-cement ratio effectively inhibited the penetration of chloride ions in the RC beam specimens. In terms of the cross-sectional loss of the steel bars, the average loss of the steel bar increases with increasing crack width for the beams with 182-day cycles, while the effect of crack width on the average loss is not as noticeable for the beams with 364-day cycles. Finally, a model is proposed to predict the relationship between the crack width influence coefficient, µ, and the crack width, w, and this model shows good agreement with the experimental results.

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