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1.
Foods ; 13(7)2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38611428

RESUMO

Obesity poses a significant threat to various health conditions such as heart diseases, diabetes, high blood pressure, and heart attack, with the gut microbiota playing a crucial role in maintaining the body's energy balance. We identified a novel probiotic fungal strain, Kluyveromyces lactis JSA 18 (K. lactis), which was isolated from yak milk and was found to possess anti-obesity properties. Additionally, Lactobacillus plantarum CGMCC 8198 (LP8198) from our previous study was also included to evaluate its anti-obesity properties. The findings indicated that K. lactis caused a notable reduction in weight gain, liver and fat indexes, and hyperlipidemia in mice fed a high-fat diet (HFD). Administering K. lactis and LP8198 to mice on a high-fat diet resulted in a reduction of serum triglyceride levels. Furthermore, the supplements reduced ALT and AST activity, and inhibited the production of inflammatory cytokines such as TNF-α and IL-1ß. In addition, lipid metabolism was enhanced by the downregulation of ACC1, PPAR-γ, SREBP-1, and Fasn. Moreover, this study found that K. lactis and LP8198 have little effect on gut bacteria. Additionally, K. lactis partially influenced intestinal fungi, while LP8198 had a minor influence on gut mycobiota. The main goal of this research was to show how effective K. lactis can be as a probiotic in combating obesity.

2.
Environ Sci Pollut Res Int ; 31(20): 29916-29929, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38594563

RESUMO

To elucidate the effects of long-term (20 years) afforestation with different woody plant species on the soil microenvironment in coal gangue polymetallic contaminated areas. This study analyzed the soil physicochemical properties, soil enzyme activities, soil ionophore, bacterial community structure, soil metabolite, and their interaction relationships at different vertical depths. Urease, sucrase, and acid phosphatase activities in the shallow soil layers increased by 4.70-7.45, 3.83-7.64, and 3.27-4.85 times, respectively, after the restoration by the four arboreal plant species compared to the plant-free control soil. Additionally, it reduced the content of available elements in the soil and alleviated the toxicity stress for Cd, Ni, Co, Cr, As, Fe, Cu, U, and Pb. After the long-term restoration of arboreal plants, the richness and Shannon indices of soil bacteria significantly increased by 4.77-23.81% and 2.93-7.93%, respectively, broadening the bacterial ecological niche. The bacterial community structure shaped by different arboreal plants exhibited high similarity, but the community similarity decreased with increasing vertical depth. Soils Zn, U, Sr, S, P, Mg, K, Fe, Cu, Ca, Ba, and pH were identified as important influencing factors for the community structure of Sphingomonas, Pseudarthrobacter, Nocardioides, and Thiobacillus. The metabolites such as sucrose, raffinose, L-valine, D-fructose 2, 6-bisphosphate, and oxoglutaric acid were found to have the greatest effect on the bacterial community in the rhizosphere soils for arboreal plants. The results of the study demonstrated that long-term planting for woody plants in gangue dumps could regulate microbial abundance and symbiotic patterns through the accumulation of rhizosphere metabolites in the soil, increase soil enzyme activity, reduce heavy metal levels, and improve the soil environment in coal gangue dumps.


Assuntos
Microbiologia do Solo , Poluentes do Solo , Solo , Solo/química , Carvão Mineral
3.
Foods ; 13(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38540913

RESUMO

Hyperuricaemia (HUA) is a disorder of purine metabolism, which manifests itself as an increase in uric acid production and a decrease in uric acid excretion, as well as a change in the structure of the intestinal microbiota. Most of the drugs currently used to treat HUA have significant side effects, and it is essential to find a treatment for HUA that is free of side effects. In this study, a novel strain, Pediococcus acidilactici GQ01, was screened from natural fermented wolfberry. The effects of both live bacteria GQ01 and its heat-killed G1PB postbiotic on HUA were investigated. The results showed that both probiotic GQ01 and G1PB postbiotics could effectively decrease blood uric acid, creatinine, and urea nitrogen levels in the HUA mice model. P. acidilactici GQ01 was more effective in inhibiting ADA activity, while G1PB postbiotics was more effective in inhibiting XOD activity. Meanwhile, GQ01 and G1PB were able to ameliorate liver and kidney tissue injury, upregulate the expression of ABCG2 in kidney and XOD gene in liver, downregulate the protein expression of URAT1 and GLUT9 in kidney, and therefore reduce the value of blood uric acid by decreasing the uric acid reabsorption and increasing the excretion of uric acid. Additionally, both probiotics and postbiotics could regulate the intestinal microbiota structure of HUA mice, so as to bring the dysfunctional intestinal composition back to normal. Furthermore, P. acidilactici GQ01 and G1PB postbiotics can increase the levels of acetic acid, propionic acid, and butyric acid in the intestinal tract, improve the intestinal function, and maintain the healthy homeostatic state of the intestinal tract. In summary, P. acidilactici GQ01 and its G1PB postbiotics may be developed as functional food or drug materials capable of treating HUA.

4.
Vet Microbiol ; 292: 110061, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38547545

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) has caused significant economic losses in the swine industry. In this study, the high-throughput sequencing, microRNAs (miRNAs) mimic, and lentivirus were used to screen for potential miRNAs that can promote PRRSV infection in porcine alveolar macrophages or Marc-145 cells. It was observed that novel-216, a previously unidentified miRNA, was upregulated through the p38 signaling pathway during PRRSV infection, and its overexpression significantly increased PRRSV replication. Further analysis revealed that novel-216 regulated PRRSV replication by directly targeting mitochondrial antiviral signaling protein (MAVS), an upstream molecule of type Ⅰ IFN that mediates the production and response of type Ⅰ IFN. The proviral function of novel-216 on PRRSV replication was abolished by MAVS overexpression, and this effect was reversed by the 3'UTR of MAVS, which served as the target site of novel-216. In conclusion, this study demonstrated that PRRSV-induced upregulation of novel-216 served to inhibit the production and response of typeⅠ IFN and facilitate viral replication, providing new insights into viral immune evasion and persistent infection.


Assuntos
MicroRNAs , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Doenças dos Suínos , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/genética , Regiões 3' não Traduzidas/genética , MicroRNAs/genética , Replicação Viral/fisiologia , Doenças dos Suínos/genética
5.
Microb Cell Fact ; 23(1): 61, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402145

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) causes chronic gastric disease. An efficient oral vaccine would be mucosa-targeted and offer defense against colonization of invasive infection in the digestive system. Proteolytic enzymes and acidic environment in the gastrointestinal tract (GT) can, however, reduce the effectiveness of oral vaccinations. For the creation of an edible vaccine, L. lactis has been proposed as a means of delivering vaccine antigens. RESULTS: We developed a plSAM (pNZ8148-SAM) that expresses a multiepitope vaccine antigen SAM-WAE containing Urease, HpaA, HSP60, and NAP extracellularly (named LL-plSAM-WAE) to increase the efficacy of oral vaccinations. We then investigated the immunogenicity of LL-plSAM-WAE in Balb/c mice. Mice that received LL-plSAM-WAE or SAM-WAE with adjuvant showed increased levels of antibodies against H. pylori, including IgG and sIgA, and resulted in significant reductions in H. pylori colonization. Furthermore, we show that SAM-WAE and LL-plSAM-WAE improved the capacity to target the vaccine to M cells. CONCLUSIONS: These findings suggest that recombinant L. lactis could be a promising oral mucosa vaccination for preventing H. pylori infection.


Assuntos
Helicobacter pylori , Animais , Camundongos , Imunidade nas Mucosas , Fatores de Virulência , Vacinas Bacterianas , Urease , Vacinas Sintéticas , Camundongos Endogâmicos BALB C , Administração Oral
6.
Chemosphere ; 351: 141265, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38246497

RESUMO

Plant enrichment and tolerance to heavy metals are crucial for the phytoremediation of coal gangue mountain. However, understanding of how plants mobilize and tolerate heavy metals in coal gangue is limited. This study conducted potted experiments using Setaria viridis as a pioneer remediation plant to evaluate its tolerance to coal gangue, its mobilization and enrichment of metals, and its impact on the soil environment. Results showed that the addition of 40% gangue enhanced plant metal and oxidative stress resistance, thereby promoting plant growth. However, over 80% of the gangue inhibited the chlorophyll content, photoelectron conduction rate, and biomass of S. viridis, leading to cellular peroxidative stress. An analysis of metal resistance showed that endogenous S in coal gangue promoted the accumulation of glutathione, plant metal chelators, and non-protein thiols, thereby enhancing its resistance to metal stress. Setaria viridis cultivation affected soil properties by decreasing nitrogen, phosphorus, conductivity, and urease and increasing sucrase and acid phosphatase in the rhizosphere soil. In addition, S. viridis planting increased V, Cr, Ni, As, and Zn in the exchangeable and carbonate-bound states within the gangue, effectively enriching Cd, Cr, Fe, S, U, Cu, and V. The increased mobility of Cd and Pb was correlated with a higher abundance of Proteobacteria and Acidobacteria. Heavy metals, such as As, Fe, V, Mn, Ni, and Cu, along with environmental factors, including total nitrogen, total phosphorus, urease, and acid phosphatase, were the primary regulatory factors for Sphingomonas, Gemmatimonas, and Bryobacter. In summary, S. viridis adapted to gangue stress by modulating antioxidant and elemental enrichment systems and regulating the release and uptake of heavy metals through enhanced bacterial abundance and the recruitment of gangue-tolerant bacteria. These findings highlight the potential of S. viridis for plant enrichment in coal gangue areas and will aid the restoration and remediation of these environments.


Assuntos
Metais Pesados , Setaria (Planta) , Poluentes do Solo , Cádmio/farmacologia , Setaria (Planta)/metabolismo , Carvão Mineral , Urease , Metais Pesados/análise , Plantas/metabolismo , Fósforo/farmacologia , Bactérias/metabolismo , Enxofre/farmacologia , Solo , Fosfatase Ácida , Nitrogênio/farmacologia , Poluentes do Solo/análise
7.
Water Res ; 250: 121013, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38118252

RESUMO

The ecological risk of tritiated wastewater into the environment has attracted much attention. Assessing the ecological risk of tritium-containing pollution is crucial by studying low-activity tritium exposure's environmental and biological effects on freshwater micro-environment and the enrichment potential of organically bound tritium (OBT) in microalgae and aquatic plants. The impact of tritium-contaminated wastewater on the microenvironment of freshwater systems was analyzed using microcosm experiments to simulate tritium pollution in freshwater systems. Low activity tritium pollution (105 Bq/L) induced differences in microbial abundance, with Proteobacteria, Bacteroidota, and Desulfobacterota occupying important ecological niches in the water system. Low activity tritium (105-107 Bq/L) did not affect the growth of microalgae and aquatic plants, but OBT was significantly enriched in microalgae and two aquatic plants (Pistia stratiotes, Spirodela polyrrhiza), with the enrichment coefficients of 2.08-3.39 and 1.71-2.13, respectively. At the transcriptional level, low-activity tritium (105 Bq/L) has the risk of interfering with gene expression in aquatic plants. Four dominant cyanobacterial strains (Leptolyngbya sp., Synechococcus elongatus, Nostoc sp., and Anabaena sp.) were isolated and demonstrated good environmental adaptability to tritium pollution. Environmental factors can modify the tritium accumulation potential in cyanobacteria and microalgae, theoretically enhancing food chain transfer.


Assuntos
Microalgas , Trítio/análise , Águas Residuárias , Poluição Ambiental/análise , Água Doce/análise
8.
BMC Biotechnol ; 23(1): 50, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031036

RESUMO

BACKGROUND: Filamentous fungi are efficient degraders of plant biomass and the primary producers of commercial cellulolytic enzymes. While the transcriptional regulation mechanisms of cellulases have been continuously explored in lignocellulolytic fungi, the induction of cellulase production remains a complex multifactorial system, with several aspects still largely elusive. RESULTS: In this study, we identified a Zn2Cys6 transcription factor, designated as Clr-5, which regulates the expression of cellulase genes by influencing amino acid metabolism in Neurospora crassa during growth on cellulose. The deletion of clr-5 caused a significant decrease in secreted protein and cellulolytic enzyme activity of N. crassa, which was partially alleviated by supplementing with yeast extract. Transcriptomic profiling revealed downregulation of not only the genes encoding main cellulases but also those related to nitrogen metabolism after disruption of Clr-5 under Avicel condition. Clr-5 played a crucial role in the utilization of multiple amino acids, especially leucine and histidine. When using leucine or histidine as the sole nitrogen source, the Δclr-5 mutant showed significant growth defects on both glucose and Avicel media. Comparative transcriptomic analysis revealed that the transcript levels of most genes encoding carbohydrate-active enzymes and those involved in the catabolism and uptake of histidine, branched-chain amino acids, and aromatic amino acids, were remarkably reduced in strain Δclr-5, compared with the wild-type N. crassa when grown in Avicel medium with leucine or histidine as the sole nitrogen source. These findings underscore the important role of amino acid metabolism in the regulation of cellulase production in N. crassa. Furthermore, the function of Clr-5 in regulating cellulose degradation is conserved among ascomycete fungi. CONCLUSIONS: These findings regarding the novel transcription factor Clr-5 enhance our comprehension of the regulatory connections between amino acid metabolism and cellulase production, offering fresh prospects for the development of fungal cell factories dedicated to cellulolytic enzyme production in bio-refineries.


Assuntos
Celulase , Celulases , Neurospora crassa , Celulase/metabolismo , Neurospora crassa/genética , Neurospora crassa/metabolismo , Histidina/genética , Histidina/metabolismo , Leucina/genética , Leucina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Celulose/metabolismo , Celulases/genética , Nitrogênio/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica
9.
ChemistryOpen ; 12(10): e202300058, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37803405

RESUMO

The characteristics of frustrated Lewis pairs (FLPs) on albite surfaces were analyzed with density functional theory, and the reaction mechanism for H2 activation by the FLPs was studied. The results show that albite is an ideal substrate material with FLPs, and its (001) and (010) surfaces have the typical characteristics of FLPs. In the case of H2 activation, the interaction between the HOMO of H2 and the SOMO of the Lewis base and the electron acceptance characteristics of the Lewis acid are the key factors. In fact, the activation energy of H2 is the required activation energy from the ground state to the excited state, and once the excited state is produced, the dissociative adsorption of H2 will occur directly. This study provides a new ideas and a reference for research on the construction of novel solid FLPs catalysts using ultramicro channel materials.

10.
Environ Res ; 234: 116491, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37394168

RESUMO

The soil microbial diversity in the gangue accumulation area is severely stressed by a variety of heavy metals, while the influence of long-term recovery of herbaceous plants on the ecological structure of gangue-contaminated soil is to be explored. Therefore, we analysed the differences in physicochemical properties, elemental changes, microbial community structure, metabolites and expression of related pathways in soils in the 10- and 20-year herbaceous remediation areas of coal gangue. Our results showed that phosphatase, soil urease, and sucrase activities of gangue soils significantly increased in the shallow layer after herbaceous remediation. However, in zone T1 (10-year remediation zone), the contents of harmful elements, such as Thorium (Th; 1.08-fold), Arsenic (As; 0.78-fold), lead (Pb; 0.99-fold), and uranium (U; 0.77-fold), increased significantly, whereas the soil microbial abundance and diversity also showed a significant decreasing trend. Conversely, in zone T2 (20-year restoration zone), the soil pH significantly increased by 1.03- to 1.06-fold and soil acidity significantly improved. Moreover, the abundance and diversity of soil microorganisms increased significantly, the expression of carbohydrates in soil was significantly downregulated, and sucrose content was significantly negatively correlated with the abundance of microorganisms, such as Streptomyces. A significant decrease in heavy metals was observed in the soil, such as U (1.01- to 1.09-fold) and Pb (1.13- to 1.25-fold). Additionally, the thiamin synthesis pathway was inhibited in the soil of the T1 zone; the expression level of sulfur (S)-containing histidine derivatives (Ergothioneine) was significantly up-regulated by 0.56-fold in the shallow soil of the T2 zone; and the S content in the soil significantly reduced. Aromatic compounds were significantly up-regulated in the soil after 20 years of herbaceous plant remediation in coal gangue soil, and microorganisms (Sphingomonas) with significant positive correlations with benzene ring-containing metabolites, such as Sulfaphenazole, were identified.


Assuntos
Metais Pesados , Microbiota , Poluentes do Solo , Urânio , Carvão Mineral , Chumbo/toxicidade , Chumbo/análise , Metais Pesados/análise , Plantas , Solo/química , Metaboloma , Poluentes do Solo/toxicidade , Poluentes do Solo/análise
11.
Molecules ; 28(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37513430

RESUMO

For the purpose of regulating the visible-light-driven photocatalytic properties of photocatalysts, we selected BiOBr as the research target and various routes were used. Herein, via the use of a hydrothermal method with various solvents, BiOBr particles with controllable morphology and photocatalytic activities are obtained. In particular, through changing the volume ratio of ethylene glycol (EG) to ethanol (EtOH), BiOBr compounds possess microspheres, in which samples synthesized by using EG:EtOH = 1:2 have the highest photocatalytic activity, and can completely decompose RhB under visible light irradiation within 14 min. Furthermore, we also used different volume ratios of EG and H2O reaction solvents to prepare BiOBr particles so as to further improve its pollutant removal ability. When the volume ratio of EG to H2O is 1:1, the synthesized BiOBr particles have the best photocatalytic activity, and RhB can be degraded in only 10 min upon visible light irradiation. Aside from the reaction solvent, the impact of sintering temperature on the photocatalytic properties of BiOBr particles is also explored, where its pollutant removal capacities are restrained due to the reduced specific surface area. Additionally, the visible-light-triggered photocatalytic mechanism of BiOBr particles is determined by h+, ·OH and ·O2- active species.

12.
Environ Pollut ; 330: 121744, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37127238

RESUMO

The capacity of Spanish moss (Tillandsia usneoides), an aerial plant, to adsorb radon (Rn) and absorb CO2 was assessed to analyze its capacity to remove pollutants from indoor air and to determine its radon (Rn) tolerance mechanism. Transcriptomics and metabolomics techniques were used to analyze the response of the plant to Rn exposure. Spanish moss absorbed indoor CO2 at night using the type of photosynthesis termed crassulacean acid metabolism. The CO2 absorption efficiency of the plant was mainly affected by the light duration and diurnal temperature differences. The highest purification efficiency was 48.25%, and the scales on the Spanish moss leaf surface were the key sites for Rn adsorption. Metabolome analysis showed that Rn exposure induced differential metabolites significantly enriched in the metabolism of lipids, amino acids, nucleotides, and carbohydrates. Transcriptome analysis showed significantly upregulated expression levels of functional genes in Rn-exposed leaves. Rn had significant effects on respiratory metabolism, as indicated by upregulated expression of metabolites and functional genes related to the glycolysis pathway, pyruvate oxidation, tricarboxylic acid cycle, and oxidative phosphorylation pathway. These responses indicated that the internal mechanism by which Spanish moss alleviates Rn stress involves an enhancement of cellular energy supplies and regulation of respiratory metabolic pathways to allow adaptation to Rn pollution.


Assuntos
Poluentes Radioativos do Ar , Poluição do Ar em Ambientes Fechados , Monitoramento de Radiação , Radônio , Tillandsia , Radônio/análise , Tillandsia/química , Tillandsia/metabolismo , Adsorção , Dióxido de Carbono/análise , Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos
13.
Foods ; 12(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36900592

RESUMO

Mesenchymal stem cells (MSCs) can be used as a cell source for cultivated meat production due to their adipose differentiation potential, but MSCs lose their stemness and undergo replicative senescence during expansion in vitro. Autophagy is an important mechanism for senescent cells to remove toxic substances. However, the role of autophagy in the replicative senescence of MSCs is controversial. Here, we evaluated the changes in autophagy in porcine MSCs (pMSCs) during long-term culture in vitro and identified a natural phytochemical, ginsenoside Rg2, that could stimulate pMSC proliferation. First, some typical senescence characteristics were observed in aged pMSCs, including decreased EdU-positive cells, increased senescence-associated beta-galactosidase activity, declined stemness-associated marker OCT4 expression, and enhanced P53 expression. Importantly, autophagic flux was impaired in aged pMSCs, suggesting deficient substrate clearance in aged pMSCs. Rg2 was found to promote the proliferation of pMSCs using MTT assay and EdU staining. In addition, Rg2 inhibited D-galactose-induced senescence and oxidative stress in pMSCs. Rg2 increased autophagic activity via the AMPK signaling pathway. Furthermore, long-term culture with Rg2 promoted the proliferation, inhibited the replicative senescence, and maintained the stemness of pMSCs. These results provide a potential strategy for porcine MSC expansion in vitro.

14.
Environ Sci Technol ; 57(13): 5305-5316, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36952228

RESUMO

The potential ecological risks caused by entering radioactive wastewater containing tritium and carbon-14 into the sea require careful evaluation. This study simulated seawater's tritium and carbon-14 pollution and analyzed the effects on the seawater and sediment microenvironments. Tritium and carbon-14 pollution primarily altered nitrogen and phosphorus metabolism in the seawater environment. Analysis by 16S rRNA sequencing showed changes in the relative abundance of microorganisms involved in carbon, nitrogen, and phosphorus metabolism and organic matter degradation in response to tritium and carbon-14 exposure. Metabonomics and metagenomic analysis showed that tritium and carbon-14 exposure interfered with gene expression involving nucleotide and amino acid metabolites, in agreement with the results seen for microbial community structure. Tritium and carbon-14 exposure also modulated the abundance of functional genes involved in carbohydrate, phosphorus, sulfur, and nitrogen metabolic pathways in sediments. Tritium and carbon-14 pollution in seawater adversely affected microbial diversity, metabolic processes, and the abundance of nutrient-cycling genes. These results provide valuable information for further evaluating the risks of tritium and carbon-14 in marine environments.


Assuntos
Bactérias , Microbiota , Radioisótopos de Carbono/metabolismo , Trítio/metabolismo , Bactérias/genética , Bactérias/metabolismo , RNA Ribossômico 16S/genética , Microbiota/genética , Água do Mar , Redes e Vias Metabólicas , Carbono/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Sedimentos Geológicos/química
15.
Molecules ; 28(3)2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36770703

RESUMO

The characteristics of active sites on the surface of albite were theoretically analyzed by density functional theory, and the activation of the C-H bond of methane using an albite catalyst and the reaction mechanism of preparing C2 hydrocarbons by nonoxidative coupling were studied. There are two frustrated Lewis pairs (FLPs) on the (001) and (010) surfaces of albite; they can dissociate H2 under mild conditions and show high activity for the activation of methane C-H bonds. CH4 molecules can undergo direct dissociative adsorption on the (010) surface, whereas a 50.07 kJ/mol activation barrier is needed on the (001) surface. The prepared albite catalyst has a double combination function of the (001) and (010) surfaces; these surfaces produce a spillover phenomenon in the process of CH4 activation reactions, where CH3 overflows from the (001) surface with CH3 adsorbed on the (010) surface to achieve nonoxidative high efficiently C-C coupling with an activation energy of 18.51 kJ/mol. At the same time, this spillover phenomenon inhibits deep dehydrogenation, which is conducive to the selectivity of the C2 hydrocarbons. The experimental results confirm that the selectivity of the C2 hydrocarbons is maintained above 99% in the temperature range of 873 K to 1173 K.

16.
Environ Pollut ; 323: 121279, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36791945

RESUMO

The ecological risk posed by tritium (T) and carbon-14 (C-14) discharge from nuclear accidents has gained attention. This study evaluated the toxic impact of T and C-14 (at a concentration of 37 kBq/L for 15 days) on the cyanobacteria (Synechococcus elongatus). The results showed that the assimilation efficiency of cyanobacteria was significantly higher for C-14 than T, and the intracellular C-14 activity reached 30.62-40.58 kBq/kg. T and C-14 exposure had no significant effect on cell proliferation but impacted photosynthesis and respiration. T exposure increased the content of Ca, Mg, Na, P, K, and Mn, while C-14 exposure primarily affected trace element absorption in cyanobacteria. 31, 27, and 58 different metabolites (DEMs) were identified under T, C-14, and combined exposure conditions. These DEMs were enriched in the amino acid biosynthesis pathway, and nitrogen assimilation was one of the crucial pathways affected by T and C-14 exposure. The absorption of mineral elements by cyanobacteria was influenced by the variation in metabolites in the ABC transporter pathway caused by T and C-14 exposure. Our findings provide insights into the metabolic response of cyanobacteria to T and C-14 exposure and will help to guide the ecological risk evaluation of nuclear accidents.


Assuntos
Metabolômica , Fotossíntese , Radioisótopos de Carbono , Trítio , Carbono/metabolismo
17.
Foods ; 12(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36673508

RESUMO

Fumonisin (FB) is one of the most common mycotoxins contaminating feed and food, causing severe public health threat to human and animals worldwide. Until now, only several transaminases were found to reduce FB toxicity, thus, more fumonisin detoxification transaminases with excellent catalytic properties required urgent exploration for complex application conditions. Herein, through gene mining and enzymatic characterization, three novel fumonisin detoxification transaminases-FumTSTA, FumUPTA, FumPHTA-were identified, sharing only 61-74% sequence identity with reported fumonisin detoxification transaminases. Moreover, the recombinant proteins shared diverse pH reaction ranges, good pH stability and thermostability, and the recombinant protein yields were also improved by condition optimum. Furthermore, the final products were analyzed by liquid chromatography-mass spectrometry. This study provides ideal candidates for fumonisin detoxification and meets diverse required demands in food and feed industries.

18.
Macromol Biosci ; 23(3): e2200173, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36448643

RESUMO

It is always big challenges for hyaluronic acid (HA) in transmembrane absorbing and efficient delivering to the skin. Pep-1, as one of the cell-penetrating peptides, has been documented to permeate various substances across cellular membranes without covalent binding. Here, a novel hyaluronic acid binding peptide (named HaBP) is designed, and then combined with Pep-1 to enhance the cell-penetrating efficiency of HA. The results of ELISA and immunofluorescence assay show that HaBP could bind with HA very well, and a combination of Pep-1 and HaBP could efficiently improve the transmembrane ability of HA. Furthermore, HA gradually enters the dermis from the surface of the skin in mice when it is administrated with both HaBP and Pep-1, while there are no obvious allergies or other adverse reactions during this process. This study finds a new method to promote the efficient transmembrane and transdermal absorption of HA, and throws some light on further research on the development of hyaluronic acid and its related cosmetics or drugs.


Assuntos
Ácido Hialurônico , Absorção Cutânea , Camundongos , Animais , Ácido Hialurônico/química , Peptídeos/química , Pele/metabolismo , Membrana Celular/metabolismo
19.
J Hazard Mater ; 443(Pt A): 130159, 2023 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-36283218

RESUMO

Tritium is the main component of radioactive wastewater from nuclear power plants and can be migrated into organisms to form organically bound tritium (OBT), which may pose a potential risk to aquatic ecosystem. Hence, it is essential to monitor OBT conversion in the presence of tritium exposure. In this study, the effects of pretreatment methods such as digestion on the recovery of tritium were discussed. It was found that microwave digestion pretreatment could improve the recovery of tritium by up to 90 % and allow OBT measurement with a small sample size equivalent to about 60 mg (dry weight). In addition, the efficiency of OBT transformation was different among biological samples, and the radiation hormesis phenomenon was induced by tritium exposure (3.7 × 106 Bq/L) in microalgae Chlorella vulgaris(C. vulgaris). The tritium exposure may induce radiation hormesis through the reactive oxygen species (ROS) signaling pathway, thus improving the photosynthetic capacity and metabolism level of C. vulgaris. Furthermore, enhancement of photorespiration metabolism and the antioxidation system may be important means for C. vulgaris to balance damage by tritium radiation. This study provides insights for further investigating OBT behavior, and will contribute to understanding the equilibrium damage mechanism of algae exposed to tritium.


Assuntos
Chlorella vulgaris , Monitoramento de Radiação , Trítio , Espécies Reativas de Oxigênio , Monitoramento de Radiação/métodos , Ecossistema , Hormese , Chlorella vulgaris/metabolismo , Transdução de Sinais
20.
J Agric Food Chem ; 70(41): 13186-13199, 2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36194761

RESUMO

This study investigated the influence of chitosan oligosaccharides (COSs) on a thioacetamide-induced hepatic encephalopathy (HE) Wistar rat model. COS treatment statistically reduced the false neurotransmitters and blood ammonia in HE rats, along with the suppression of oxidative stress and inflammation. The disbalanced gut microbiota was detected in HE rats by 16S rDNA sequencing, but the abundance alterations of some intestinal bacteria at either the phylum or genus level were at least partly restored by COS treatment. According to metabolomics analysis of rat feces, six metabolism pathways with the greatest response to HE were screened, several of which were remarkably reversed by COS. The altered metabolites might serve as a bridge for the alleviated HE rats treated with COS and the enhanced intestinal bacterial structure. This study provides novel guidance to develop novel food or dietary supplements to improve HE diseases due to the potential beneficial effect of COS on gut-liver axis.


Assuntos
Quitosana , Microbioma Gastrointestinal , Encefalopatia Hepática , Animais , Ratos , Encefalopatia Hepática/tratamento farmacológico , Encefalopatia Hepática/metabolismo , Encefalopatia Hepática/microbiologia , Quitosana/farmacologia , Amônia/farmacologia , Tioacetamida , Ratos Wistar , DNA Ribossômico , Oligossacarídeos/farmacologia
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