-
International Journal of Molecular... Jun 2024A family of bifunctional dihetarylmethanes and dibenzoxanthenes is assembled via a reaction of acetals containing a 2-chloroacetamide moiety with phenols and related...
A family of bifunctional dihetarylmethanes and dibenzoxanthenes is assembled via a reaction of acetals containing a 2-chloroacetamide moiety with phenols and related oxygen-containing heterocycles. These compounds demonstrated selective antitumor activity associated with the induction of cell apoptosis and inhibition of the process of glycolysis. In particular, bis(heteroaryl)methane containing two 4-hydroxy-6-methyl-2-pyran-2-one moieties combine excellent in vitro antitumor efficacy with an IC of 1.7 µM in HuTu-80 human duodenal adenocarcinoma models with a high selectivity index of 73. Overall, this work highlights the therapeutic potential of dimeric compounds assembled from functionalized acetals and builds a starting point for the development of a new family of anticancer agents.
Topics: Humans; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Methane; Cell Proliferation; Xanthenes
PubMed: 38928428
DOI: 10.3390/ijms25126724 -
Nature Communications Jun 2024Borgs are huge extrachromosomal elements (ECE) of anaerobic methane-consuming "Candidatus Methanoperedens" archaea. Here, we used nanopore sequencing to validate...
Borgs are huge extrachromosomal elements (ECE) of anaerobic methane-consuming "Candidatus Methanoperedens" archaea. Here, we used nanopore sequencing to validate published complete genomes curated from short reads and to reconstruct new genomes. 13 complete and four near-complete linear genomes share 40 genes that define a largely syntenous genome backbone. We use these conserved genes to identify new Borgs from peatland soil and to delineate Borg phylogeny, revealing two major clades. Remarkably, Borg genes encoding nanowire-like electron-transferring cytochromes and cell surface proteins are more highly expressed than those of host Methanoperedens, indicating that Borgs augment the Methanoperedens activity in situ. We reconstructed the first complete 4.00 Mbp genome for a Methanoperedens that is inferred to be a Borg host and predicted its methylation motifs, which differ from pervasive TC and CC methylation motifs of the Borgs. Thus, methylation may enable Methanoperedens to distinguish their genomes from those of Borgs. Very high Borg to Methanoperedens ratios and structural predictions suggest that Borgs may be capable of encapsulation. The findings clearly define Borgs as a distinct class of ECE with shared genomic signatures, establish their diversification from a common ancestor with genetic inheritance, and raise the possibility of periodic existence outside of host cells.
Topics: Genome, Archaeal; Methane; Phylogeny; Oxidation-Reduction; Archaea; Nanopore Sequencing; DNA Methylation; Soil Microbiology
PubMed: 38926353
DOI: 10.1038/s41467-024-49548-8 -
Nature Communications Jun 2024Tuning the oxygen activity in perovskite oxides (ABO) is promising to surmount the trade-off between activity and selectivity in redox reactions. However, this remains...
Tuning the oxygen activity in perovskite oxides (ABO) is promising to surmount the trade-off between activity and selectivity in redox reactions. However, this remains challenging due to the limited understanding in its activation mechanism. Herein, we propose the discovery that generating subsurface A-site cation (La) vacancy beneath surface Fe-O layer greatly improved the oxygen activity in LaFeO, rendering enhanced methane conversion that is 2.9-fold higher than stoichiometric LaFeO while maintaining high syngas selectivity of 98% in anaerobic oxidation. Experimental and theoretical studies reveal that absence of La-O interaction lowered the electron density over oxygen and improved the oxygen mobility, which reduced the barrier for C-H bond cleavage and promoted the oxidation of C-atom, substantially boosting methane-to-syngas conversion. This discovery highlights the importance of A-site cations in modulating electronic state of oxygen, which is fundamentally different from the traditional scheme that mainly credits the redox activity to B-site cations and can pave a new avenue for designing prospective redox catalysts.
PubMed: 38926349
DOI: 10.1038/s41467-024-49776-y -
Veterinary Sciences May 2024Almond hulls (AH) are frequently used in dairy ruminant feeding, but information on variability of their nutritive value and their potential effects on CH production is...
Chemical Composition and Nutritive Value of Almond Hulls from Two Almond Varieties and Influence of Including Almond Hulls in the Diet on In Vitro Ruminal Fermentation and Methane Production.
Almond hulls (AH) are frequently used in dairy ruminant feeding, but information on variability of their nutritive value and their potential effects on CH production is still scarce. The influence of almond variety (Guara vs. Soleta) on chemical composition and energy value of AH was investigated using 10 samples per variety collected in 2 consecutive years. Guara-AH had greater ( ≤ 0.015) ash, protein, and fat content, but lower ( ≤ 0.001) fiber than Soleta-AH. The metabolizable energy content estimated from chemical composition and in vitro gas production was 8.5% greater for Guara than for Soleta samples. Harvesting year significantly affected most of the chemical fractions. The in vitro ruminal fermentation of diets for dairy ruminants including increasing amounts of dried AH (8, 16 and 24% of the total diet; fresh matter basis) indicated that AH can be included up to 16% of the diet, partially substituting corn, wheat bran and sugar beet pulp without detrimental effects on in vitro volatile fatty acid (VFA) production. In contrast, when AH replaced alfalfa hay and corn, VFA production was reduced at all levels of AH inclusion. No antimethanogenic effects of AH were detected in the in vitro incubations.
PubMed: 38921989
DOI: 10.3390/vetsci11060242 -
Membranes May 2024This paper presents the results of adsorption and permeation experiments of hydrogen and methane at elevated temperatures on a carbon-based nanoporous membrane material...
This paper presents the results of adsorption and permeation experiments of hydrogen and methane at elevated temperatures on a carbon-based nanoporous membrane material provided by Fraunhofer IKTS. The adsorption of pure components was measured between 90 °C and 120°C and pressures up to 45 bar. The Langmuir adsorption isotherm shows the best fit for all data points. Compared to available adsorption isotherms of H and CH on carbon, the adsorption on the investigated nanoporous carbon structures is significantly lower. Single-component permeation experiments were conducted on membranes at temperatures up to 220 °C. After combining the experimental results with a Maxwell-Stefan surface diffusion model, Maxwell-Stefan surface diffusion coefficients Dis were calculated. The calculated values are in line with an empirical model and thus can be used in future multi-component modeling approaches in order to better analyze and design a membrane system. The published adsorption data fill a gap in the available adsorption data for CH and H.
PubMed: 38921490
DOI: 10.3390/membranes14060123 -
RSC Advances Jun 2024Engineering the interfacial interaction between the active metal element and support material is a promising strategy for improving the performance of catalysts toward...
Engineering the interfacial interaction between the active metal element and support material is a promising strategy for improving the performance of catalysts toward CO methanation. Herein, the Ni-doped rare-earth metal-based A-site substituted perovskite-type oxide catalysts (Ni/AMnO; A = Sm, La, Nd, Ce, Pr) were synthesized by auto-combustion method, thoroughly characterized, and evaluated for CO methanation reaction. The XRD analysis confirmed the perovskite structure and the formation of nano-size particles with crystallite sizes ranging from 18 to 47 nm. The Ni/CeMnO catalyst exhibited a higher CO conversion rate of 6.6 × 10 mol g s and high selectivity towards CH formation due to the surface composition of the active sites and capability to activate CO molecules under redox property adopted associative and dissociative mechanisms. The higher activity of the catalyst could be attributed to the strong metal-support interface, available active sites, surface basicity, and higher surface area. XRD analysis of spent catalysts showed enlarged crystallite size, indicating particle aggregation during the reaction; nevertheless, the cerium-containing catalyst displayed the least increase, demonstrating resilience, structural stability, and potential for CO methanation reaction.
PubMed: 38919281
DOI: 10.1039/d4ra02106a -
Scientific Reports Jun 2024As the mechanization of the CBM extraction process advances and geological conditions continuously evolve, the production data from CBM wells is deviating increasingly...
As the mechanization of the CBM extraction process advances and geological conditions continuously evolve, the production data from CBM wells is deviating increasingly from linearity, thereby presenting a significant challenge in accurately predicting future gas production from these wells. When it comes to predicting the production of CBM, a single deep-learning model can face several drawbacks such as overfitting, gradient explosion, and gradient disappearance. These issues can ultimately result in insufficient prediction accuracy, making it important to carefully consider the limitations of any given model. It's impressive to see how advanced technology can enhance the prediction accuracy of CBM. In this paper, the use of a CNN model to extract features from CBM well data and combine it with Bi-LSTM and a Multi-Head Attention mechanism to construct a production prediction model for CBM wells-the CNN-BL-MHA model-is fascinating. It is even more exciting that predictions of gas production for experimental wells can be conducted using production data from Wells W1 and W2 as the model's database. We compared and analyzed the prediction results obtained from the CNN-BL-MHA model we constructed with those from single models like ARIMA, LSTM, MLP, and GRU. The results show that the CNN-BL-MHA model proposed in the study has shown promising results in improving the accuracy of gas production prediction for CBM wells. It's also impressive that this model demonstrated super stability, which is essential for reliable predictions. Compared to the single deep learning model used in this study, its prediction accuracy can be improved up to 35%, and the prediction results match the actual yield data with lower error.
PubMed: 38918551
DOI: 10.1038/s41598-024-65606-z -
Scientific Reports Jun 2024Carbon-rich peat soils have been drained and used extensively for agriculture throughout human history, leading to significant losses of their soil carbon. One solution...
Carbon-rich peat soils have been drained and used extensively for agriculture throughout human history, leading to significant losses of their soil carbon. One solution for rewetting degraded peat is wet crop cultivation. Crops such as rice, which can grow in water-saturated conditions, could enable agricultural production to be maintained whilst reducing CO and NO emissions from peat. However, wet rice cultivation can release considerable methane (CH). Water table and soil management strategies may enhance rice yield and minimize CH emissions, but they also influence plant biomass allocation strategies. It remains unclear how water and soil management influences rice allocation strategies and how changing plant allocation and associated traits, particularly belowground, influence CH-related processes. We examined belowground biomass (BGB), aboveground biomass (AGB), belowground:aboveground ratio (BGB:ABG), and a range of root traits (root length, root diameter, root volume, root area, and specific root length) under different soil and water treatments; and evaluated plant trait linkages to CH. Rice (Oryza sativa L.) was grown for six months in field mesocosms under high (saturated) or low water table treatments, and in either degraded peat soil or degraded peat covered with mineral soil. We found that BGB and BGB:AGB were lowest in water saturated conditions where mineral soil had been added to the peat, and highest in low-water table peat soils. Furthermore, CH and BGB were positively related, with BGB explaining 60% of the variation in CH but only under low water table conditions. Our results suggest that a mix of low water table and mineral soil addition could minimize belowground plant allocation in rice, which could further lower CH likely because root-derived carbon is a key substrate for methanogenesis. Minimizing root allocation, in conjunction with water and soil management, could be explored as a strategy for lowering CH emissions from wet rice cultivation in degraded peatlands.
Topics: Oryza; Methane; Soil; Plant Roots; Biomass; Agriculture; Crops, Agricultural; Water
PubMed: 38918514
DOI: 10.1038/s41598-024-64616-1 -
Nature Communications Jun 2024Anaerobic digestion of organic waste into methane and carbon dioxide (biogas) is carried out by complex microbial communities. Here, we use full-length 16S rRNA gene...
Anaerobic digestion of organic waste into methane and carbon dioxide (biogas) is carried out by complex microbial communities. Here, we use full-length 16S rRNA gene sequencing of 285 full-scale anaerobic digesters (ADs) to expand our knowledge about diversity and function of the bacteria and archaea in ADs worldwide. The sequences are processed into full-length 16S rRNA amplicon sequence variants (FL-ASVs) and are used to expand the MiDAS 4 database for bacteria and archaea in wastewater treatment systems, creating MiDAS 5. The expansion of the MiDAS database increases the coverage for bacteria and archaea in ADs worldwide, leading to improved genus- and species-level classification. Using MiDAS 5, we carry out an amplicon-based, global-scale microbial community profiling of the sampled ADs using three common sets of primers targeting different regions of the 16S rRNA gene in bacteria and/or archaea. We reveal how environmental conditions and biogeography shape the AD microbiota. We also identify core and conditionally rare or abundant taxa, encompassing 692 genera and 1013 species. These represent 84-99% and 18-61% of the accumulated read abundance, respectively, across samples depending on the amplicon primers used. Finally, we examine the global diversity of functional groups with known importance for the anaerobic digestion process.
Topics: Archaea; RNA, Ribosomal, 16S; Anaerobiosis; Bacteria; Microbiota; Biodiversity; Phylogeny; Wastewater; Bioreactors; Methane; Sequence Analysis, DNA
PubMed: 38918384
DOI: 10.1038/s41467-024-49641-y -
Microbiology Spectrum Jun 2024Soil microorganisms are the most active participants in terrestrial ecosystems, and have key roles in biogeochemical cycles and ecosystem functions. Despite the...
UNLABELLED
Soil microorganisms are the most active participants in terrestrial ecosystems, and have key roles in biogeochemical cycles and ecosystem functions. Despite the extensive research on soil pH as a key predictor of microbial community and composition, a limitation of these studies lies in determining whether bacterial and/or fungal communities are directly or indirectly influenced by pH. We conducted a controlled laboratory experiment to investigate the effects of soil pH amendment (+/- 1-2 units) with six levels on soil microbial communities in two contrasting Chinese agricultural soils (pH 8.43 in Dezhou, located in the North China Plain, Shandong vs pH 6.17 in Wuxi, located in the Taihu Lake region, Jiangsu, east China). Results showed that the fungal diversity and composition were related to soil pH, but the effects were much lower than the effects of soil pH on bacterial community in two soils. The diversity and composition of bacterial communities were more closely associated with soil pH in Wuxi soils compared to Dezhou soils. The alpha diversity of bacterial communities peaked near pH levels in both soils, displaying a quadratic fitting pattern. Redundancy analysis and variation partition analysis indicated that soil pH affected bacterial community and composition by directly imposing a physiological constraint on soil bacteria and indirectly altering soil characteristics (e.g., nutrient availability). The study also examined complete curves of taxa relative abundances at the phylum and family levels in response to soil pH, with most relationships conforming to a quadratic fitting pattern, indicating soil pH is a reliable predictor. Furthermore, soil pH amendment affected the transformation of nitrogen and the abundances of functional genes involved in the nitrogen cycle, and methane production and consumption. Overall, results from this study would enhance our comprehension of how soil microorganisms in contrasting farmlands will respond to soil pH changes, and would contribute to more effective soil management and conservation strategies.
IMPORTANCE
This study delves into the impact of soil pH on microbial communities, investigating whether pH directly or indirectly influences bacterial and fungal communities. The research involved two contrasting soils subjected to a 1-2 pH unit amendment. Results indicate bacterial community composition was shaped by soil pH through physiological constraints and nutrient limitations. We found that most taxa relative abundances at the phylum and family levels responded to pH with a quadratic fitting pattern, indicating that soil pH is a reliable predictor. Additionally, soil pH was found to significantly influence the predicted abundance of functional genes involved in the nitrogen cycle as well as in methane production and consumption processes. These insights can contribute to develop more effective soil management and conservation strategies.
PubMed: 38916324
DOI: 10.1128/spectrum.04165-23