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1.
Environ Sci Ecotechnol ; 21: 100438, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39036799

ABSTRACT

Ethane, the second most abundant gaseous hydrocarbon in vast anoxic environments, is an overlooked greenhouse gas. Microbial anaerobic oxidation of ethane can be driven by available electron acceptors such as sulfate and nitrate. However, despite nitrite being a more thermodynamically feasible electron acceptor than sulfate or nitrate, little is known about nitrite-driven anaerobic ethane oxidation. In this study, a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through the long-term operation of a nitrite-and-ethane-fed bioreactor. During continuous operation, the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO2 -N L-1 d-1 and 11.48 mg C2H6 L-1 d-1, respectively. Batch tests demonstrated that ethane is essential for nitrite removal in this microbial culture. Metabolic function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae, designated as 'Candidatus Alkanivoras nitrosoreducens', may perform the nitrite-driven anaerobic ethane oxidation. In the proposed metabolic model, despite the absence of known genes for ethane conversion to ethyl-succinate and succinate-CoA ligase, 'Ca. A. nitrosoreducens' encodes a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to nitrogen. These findings advance our understanding of nitrite-driven anaerobic ethane oxidation, highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.

2.
Fitoterapia ; 177: 106096, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38936672

ABSTRACT

Two new ent-labdane diterpenoids, hypoestesins A-B (1-2) and five new labdane diterpenoids, hypopurolides H-L (3-7), were isolated from the aerial parts of Hypoestes purpurea. All of the structures were fully determined based on extensive analysis of 1H, 13C, 2D NMR, and HRESIMS data. The absolute configurations of 1-3 was established through comparing the experimental and calculated ECD curves and the structure of 5 was confirmed by single crystal X-ray diffraction experiment. Compounds 5-7 were unusual C23 labdane diterpenoids having a γ-acetonyl-α, ß-unsaturated γ-lactone unit and each assigned as C-15 epimeric mixture. Furthermore, cytotoxic and anti-inflammatory activities of 3-7 were evaluated. The results showed that 3 had remarkable cytotoxic activity against HL-60, A549, SMMC-7721, MDA-MB-231, and SW480 cancer cell lines with IC50 values ranging from 2.35 to 17.06 µM. Compound 4 showed moderate cytotoxic activity against HL-60 and SMMC-7721 cancer cell lines with IC50 values of 15.12 ± 0.53 and 12.92 ± 0.60 µM, respectively. Furthermore, compound 4 was also found to exhibit inhibitory activity against NO production in RAW 264.7 macrophages with IC50 values of 23.56 ± 0.99 µM, compared to the positive control L-NMMA with an IC50 value of 41.11 ± 1.34 µM.

3.
Phytochemistry ; 225: 114189, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38905919

ABSTRACT

Eight previously undescribed diterpenoids, caesamins A-H (1-8), were separated and identified from the seeds of Caesalpinia minax Hance. Their structures were characterized by extensive spectroscopic data and X-ray crystallographic analysis. Structurally, caesamin A (1) is the first cassane-type diterpenoid with a C23 carbon skeleton containing an unusual isopropyl. Caesamin F (6) represents the first example of cleistanthane diterpenoid from the genus Caesalpinia. Caesamins B (2) and F (6) exhibited inhibitory activity against LPS-induced nitric oxide production in RAW 264.7 macrophages with IC50 values of 45.67 ± 0.92 and 42.99 ± 0.24 µM, comparable to positive control 43.69 ± 2.62 µM of NG-Monomethyl-L-arginine. Furthermore, the chemotaxonomic significance of the isolates was discussed.


Subject(s)
Caesalpinia , Diterpenes , Nitric Oxide , Seeds , Caesalpinia/chemistry , Diterpenes/chemistry , Diterpenes/pharmacology , Diterpenes/isolation & purification , Mice , Seeds/chemistry , Animals , RAW 264.7 Cells , Nitric Oxide/antagonists & inhibitors , Nitric Oxide/biosynthesis , Molecular Structure , Lipopolysaccharides/pharmacology , Lipopolysaccharides/antagonists & inhibitors , Macrophages/drug effects , Structure-Activity Relationship , Dose-Response Relationship, Drug
4.
PLoS One ; 19(6): e0302687, 2024.
Article in English | MEDLINE | ID: mdl-38848398

ABSTRACT

Xenogenesis has been recognized as a prospective method for producing channel catfish, Ictalurus punctatus ♀ × blue catfish, I. furcatus ♂ hybrids. The xenogenesis procedure can be achieved by transplanting undifferentiated stem cells derived from a donor fish into a sterile recipient. Xenogenesis for hybrid catfish embryo production has been accomplished using triploid channel catfish as a surrogate. However, having a surrogate species with a shorter maturation period, like white catfish (Ameiurus catus), would result in reduced feed costs, labor costs, and smaller body size requirements, making it a more suitable species for commercial applications where space is limited, and as a model species. Hence, the present study was conducted to assess the effectiveness of triploid white catfish as a surrogate species to transplant blue catfish stem cells (BSCs) and channel catfish stem cells (CSCs). Triploid white catfish fry were injected with either BSCs or CSCs labeled with PKH 26 fluorescence dye from 0 to 12 days post hatch (DPH). No significant differences in weight and length of fry were detected among BSCs and CSCs injection times (0 to 12 DPH) when fry were sampled at 45 and 90 DPH (P > 0.05). The highest survival was reported when fry were injected between 4.0 to 5.5 DPH (≥ 81.2%). At 45 and 90 DPH, cell and cluster area increased for recipients injected from 0 to 5.2 DPH, and the highest cluster area values were reported between 4.0 to 5.2 DPH. Thereafter, fluorescent cell and cluster area in the host declined with no further decrease after 10 DPH. At 45 DPH, the highest percentage of xenogens were detected when fry were injected with BSCs between 4.0 to 5.0 and CSCs between 3.0 to 5.0 DPH. At 90 DPH, the highest number of xenogens were detected from 4.0 to 6.0 DPH when injected with either BSCs or CSCs. The current study demonstrated the suitability of white catfish as a surrogate species when BSCs and CSCs were transplanted into triploid white catfish between 4.0 to 6.0 DPH (27.4 ± 0.4°C). Overall, these findings allow enhanced efficiency of commercializing xenogenic catfish carrying gametes of either blue catfish or channel catfish.


Subject(s)
Aquaculture , Catfishes , Triploidy , Animals , Aquaculture/methods , Stem Cells/cytology , Stem Cells/metabolism , Stem Cell Transplantation/methods , Ictaluridae/genetics , Female , Male
5.
Genetics ; 2024 May 29.
Article in English | MEDLINE | ID: mdl-38809057

ABSTRACT

In F1 hybrids, phenotypic values are expected to be near the parental means under additive effects or close to one parent under dominance. However, F1 traits can fall outside the parental range, and outbreeding depression occurs when inferior fitness is observed in hybrids. Another possible outcome is heterosis, a phenomenon that interspecific hybrids or intraspecific crossbred F1s exhibit improved fitness compared to both parental species or strains. As an application of heterosis, hybrids between channel catfish females and blue catfish males are superior in feed conversion efficiency, carcass yield, and harvestability. Over twenty years of hybrid catfish production in experimental settings and farming practices generated abundant phenotypic data, making it an ideal system to investigate heterosis. In this study, we characterized fitness in terms of growth and survival longitudinally, revealing environment-dependent heterosis. In ponds, hybrids outgrow both parents due to an extra rapid growth phase of 2∼4 months in year 2. This bimodal growth pattern is unique to F1 hybrids in pond culture environments only. In sharp contrast, the same genetic types cultured in tanks display outbreeding depression, where hybrids perform poorly, while channel catfish demonstrate superiority in growth throughout development. Our findings represent the first example, known to the authors, of opposite fitness shifts in response to environmental changes in interspecific vertebrate hybrids, suggesting a broader fitness landscape for F1 hybrids. Future genomic studies based on this experiment will help understand genome-environment interaction in shaping the F1 progeny fitness in the scenario of environment-dependent heterosis and outbreeding depression.

6.
Sci Total Environ ; 931: 172901, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38697549

ABSTRACT

High nitrate pollution in agriculture and industry poses a challenge to emerging methane oxidation coupled denitrification. In this study, an efficient nitrate removal efficiency of 100 % was achieved at an influent loading rate of 400 mg-N/L·d, accompanied by the production of short chain fatty acids (SCFAs) with a maximum value of 80.9 mg/L. Batch tests confirmed that methane was initially converted to acetate, which then served as a carbon source for denitrification. Microbial community characterization revealed the dominance of heterotrophic denitrifiers, including Simplicispira (22.8 %), Stappia (4.9 %), and the high­nitrogen-tolerant heterotrophic denitrifier Diaphorobacter (19.0 %), at the nitrate removal rate of 400 mg-N/L·d. Notably, the low abundance of methanotrophs ranging from 0.24 % to 3.75 % across all operational stages does not fully align with the abundance of pmoA genes, suggesting the presence of other functional microorganisms capable of methane oxidation and SCFAs production. These findings could facilitate highly efficient denitrification driven by methane and contributed to the development of denitrification using methane as an electron donor.


Subject(s)
Denitrification , Fatty Acids, Volatile , Methane , Methane/metabolism , Fatty Acids, Volatile/metabolism , Waste Disposal, Fluid/methods , Microbial Interactions , Nitrates/metabolism , Bioreactors/microbiology
7.
Environ Res ; 255: 119209, 2024 Aug 15.
Article in English | MEDLINE | ID: mdl-38782336

ABSTRACT

Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) process is a promising wastewater treatment technology, but the slow microbial growth rate greatly hinders its practical application. Although high-level nitrogen removal and excellent biomass accumulation have been achieved in n-DAMO granule process, the formation mechanism of n-DAMO granules remains unresolved. To elucidate the role of functional microbes in granulation, this study attempted to cultivate granules dominated by n-DAMO microorganisms and granules coupling n-DAMO with anaerobic ammonium oxidation (Anammox). After long-term operation, dense granules were developed in the two systems where both n-DAMO archaea and n-DAMO bacteria were enriched, whereas granulation did not occur in the other system dominated by n-DAMO bacteria. Extracellular polymeric substances (EPS) measurement indicated the critical role of EPS production in the granulation of n-DAMO process. Metagenomic and metatranscriptomic analyses revealed that n-DAMO archaea and Anammox bacteria were active in EPS biosynthesis, while n-DAMO bacteria were inactive. Consequently, more EPS were produced in the systems containing n-DAMO archaea and Anammox bacteria, leading to the successful development of n-DAMO granules. Furthermore, EPS biosynthesis in n-DAMO systems is potentially regulated by acyl-homoserine lactones and c-di-GMP. These findings not only provide new insights into the mechanism of granule formation in n-DAMO systems, but also hint at potential strategies for management of the granule-based n-DAMO process.


Subject(s)
Archaea , Bacteria , Oxidation-Reduction , Archaea/metabolism , Archaea/genetics , Anaerobiosis , Bacteria/metabolism , Bacteria/genetics , Methane/metabolism , Waste Disposal, Fluid/methods , Nitrates/metabolism , Ammonium Compounds/metabolism , Nitrites/metabolism , Extracellular Polymeric Substance Matrix/metabolism , Bioreactors/microbiology , Wastewater/microbiology
8.
Bioresour Technol ; 403: 130903, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38801958

ABSTRACT

Sulfate-dependent ammonium oxidation (Sulfammox) is a critical process linking nitrogen and sulfur cycles. However, the metabolic pathway of microbes driven Sulfammox is still in suspense. The study demonstrated that ammonium was not consumed with sulfate as the sole electron acceptor during long-term enrichment, probably due to inhibition from sulfide accumulation, while ammonium was removed at âˆ¼ 10 mg N/L/d with sulfate and nitrate as electron acceptors. Ammonium and sulfate were converted into nitrogen gas, sulfide, and elemental sulfur. Sulfammox was mainly performed by Candidatus Brocadia sapporoensis and Candidatus Brocadia fulgida, both of which encoded ammonium oxidation pathway and dissimilatory sulfate reduction pathway. Not sulfide-driven autotrophic denitrifiers but Candidatus Kuenenia stuttgartiensis converted nitrate to nitrite with sulfide. The results of this study reveal the specialized metabolism of Sulfammox bacteria (Candidatus Brocadia sapporoensis and Candidatus Brocadia fulgida) and provide insight into microbial relationships during the nitrogen and sulfur cycles.


Subject(s)
Nitrogen , Oxidation-Reduction , Sulfates , Sulfur , Sulfur/metabolism , Sulfates/metabolism , Nitrogen/metabolism , Anaerobiosis , Ammonium Compounds/metabolism , Nitrates/metabolism , Sulfides/metabolism
9.
Water Res ; 256: 121571, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38583332

ABSTRACT

'Candidatus Methanoperedens nitroreducens' is an archaeal methanotroph with global importance that links carbon and nitrogen cycles and great potential for sustainable operation of wastewater treatment. It has been reported to mediate the anaerobic oxidation of methane through a reverse methanogenesis pathway while reducing nitrate to nitrite. Here, we demonstrate that 'Ca. M. nitroreducens' reduces ferric iron forming ammonium (23.1 %) and nitrous oxide (N2O, 46.5 %) from nitrate. These results are supported with the upregulation of genes coding for proteins responsible for dissimilatory nitrate reduction to ammonium (nrfA), N2O formation (norV, cyt P460), and multiple multiheme c-type cytochromes for ferric iron reduction. Concomitantly, an increase in the N2O-reducing SJA-28 lineage and a decrease in the nitrite-reducing 'Candidatus Methylomirabilis oxyfera' are consistent with the changes in 'Ca. M. nitroreducens' end products. These findings demonstrate the highly flexible physiology of 'Ca. M. nitroreducens' in anaerobic ecosystems with diverse electron acceptor conditions, and further reveals its roles in linking methane oxidation to global biogeochemical cycles. 'Ca. M. nitroreducens' could significantly affect the bioavailability of nitrogen sources as well as the emission of greenhouse gas in natural ecosystems and wastewater treatment plants.


Subject(s)
Ammonium Compounds , Methane , Nitrates , Nitrous Oxide , Oxidation-Reduction , Methane/metabolism , Nitrous Oxide/metabolism , Ammonium Compounds/metabolism , Anaerobiosis , Nitrates/metabolism , Ferric Compounds/metabolism
10.
Phytochemistry ; 222: 114105, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38657886

ABSTRACT

Three undescribed cassane diterpenoids, caesalpanins D-F (1-3), and seven known ones were isolated from the seeds of Caesalpinia sappan. Structures and absolute configurations of 1-3 were elucidated based on the extensive spectroscopic analysis, single-crystal X-ray diffraction analysis, and ECD calculations. Structurally, compound 1 was the first example of 18-norcassane diterpenoid and 2 was a rare 20-norcassane diterpenoid having an unusual five-membered oxygen bridge between C-10/C-18. The anti-proliferative activity of 1, 3, and 4-10 against PANC-1 cells (pancreatic ductal adenocarcinoma cell line) was evaluated, and phanginin H (4) was found to exhibit anti-cancer activity with IC50 value of 18.13 ± 0.63 µM. Compound 4 inhibited PANC-1 cell growth by arresting the cell cycle at G2/M phase via regulation of cyclin-dependent kinases, and the self-renewal and metastasis of PANC-1 cells by suppressing cancer cell stemness. Furthermore, compound 4 induced ROS generation and subsequently activated autophagy, which was demonstrated by the formation of autophagic vacuoles and dynamic change of autophagic flux. The induced ROS accumulation resulted in AMPK activation and subsequently regulation of mTORC1 activity and ULK phosphorylation, indicating that 4 triggered autophagy through ROS/AMPK/mTORC1 pathway. These findings suggested that 4 might potentially be an autophagy inducer for the therapy of pancreatic cancer.


Subject(s)
AMP-Activated Protein Kinases , Antineoplastic Agents, Phytogenic , Autophagy , Caesalpinia , Cell Proliferation , Diterpenes , Drug Screening Assays, Antitumor , Mechanistic Target of Rapamycin Complex 1 , Pancreatic Neoplasms , Reactive Oxygen Species , Seeds , Caesalpinia/chemistry , Humans , Diterpenes/pharmacology , Diterpenes/chemistry , Diterpenes/isolation & purification , Seeds/chemistry , Autophagy/drug effects , Reactive Oxygen Species/metabolism , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/metabolism , AMP-Activated Protein Kinases/metabolism , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/chemistry , Mechanistic Target of Rapamycin Complex 1/metabolism , Mechanistic Target of Rapamycin Complex 1/antagonists & inhibitors , Cell Proliferation/drug effects , Molecular Structure , Cell Line, Tumor , Structure-Activity Relationship , Dose-Response Relationship, Drug
11.
Sci Total Environ ; 931: 172466, 2024 Jun 25.
Article in English | MEDLINE | ID: mdl-38626826

ABSTRACT

The burgeoning issue of plasmid-mediated resistance genes (ARGs) dissemination poses a significant threat to environmental integrity. However, the prediction of ARGs prevalence is overlooked, especially for emerging ARGs that are potentially evolving gene exchange hotspot. Here, we explored to classify plasmid or chromosome sequences and detect resistance gene prevalence by using DNABERT. Initially, the DNABERT fine-tuned in plasmid and chromosome sequences followed by multilayer perceptron (MLP) classifier could achieve 0.764 AUC (Area under curve) on external datasets across 23 genera, outperforming 0.02 AUC than traditional statistic-based model. Furthermore, Escherichia, Pseudomonas single genera based model were also be trained to explore its predict performance to ARGs prevalence detection. By integrating K-mer frequency attributes, our model could boost the performance to predict the prevalence of ARGs in an external dataset in Escherichia with 0.0281-0.0615 AUC and Pseudomonas with 0.0196-0.0928 AUC. Finally, we established a random forest model aimed at forecasting the relative conjugation transfer rate of plasmids with 0.7956 AUC, drawing on data from existing literature. It identifies the plasmid's repression status, cellular density, and temperature as the most important factors influencing transfer frequency. With these two models combined, they provide useful reference for quick and low-cost integrated evaluation of resistance gene transfer, accelerating the process of computer-assisted quantitative risk assessment of ARGs transfer in environmental field.


Subject(s)
Gene Transfer, Horizontal , Plasmids , Plasmids/genetics , Conjugation, Genetic , Drug Resistance, Bacterial/genetics , Pseudomonas/genetics
12.
J Environ Manage ; 358: 120832, 2024 May.
Article in English | MEDLINE | ID: mdl-38599089

ABSTRACT

Polyethylene (PE) is the most productive plastic product and includes three major polymers including high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) variation in the PE depends on the branching of the polymer chain and its crystallinity. Tenebrio obscurus and Tenebrio molitor larvae biodegrade PE. We subsequently tested larval physiology, gut microbiome, oxidative stress, and PE degradation capability and degradation products under high-purity HDPE, LLDPE, and LDPE powders (<300 µm) diets for 21 days at 65 ± 5% humidity and 25 ± 0.5 °C. Our results demonstrated the specific PE consumption rates by T. molitor was 8.04-8.73 mg PE ∙ 100 larvae-1⋅day-1 and by T. obscurus was 7.68-9.31 for LDPE, LLDPE and HDPE, respectively. The larvae digested nearly 40% of the ingested three PE and showed similar survival rates and weight changes but their fat content decreased by 30-50% over 21-day period. All the PE-fed groups exhibited adverse effects, such as increased benzoquinone concentrations, intestinal tissue damage and elevated oxidative stress indicators, compared with bran-fed control. In the current study, the digestive tract or gut microbiome exhibited a high level of adaptability to PE exposure, altering the width of the gut microbial ecological niche and community diversity, revealing notable correlations between Tenebrio species and the physical and chemical properties (PCPs) of PE-MPs, with the gut microbiome and molecular weight change due to biodegradation. An ecotoxicological simulation by T.E.S.T. confirmed that PE degradation products were little ecotoxic to Daphnia magna and Rattus norvegicus providing important novel insights for future investigations into the environmentally-friendly approach of insect-mediated biodegradation of persistent plastics.


Subject(s)
Biodegradation, Environmental , Larva , Microplastics , Polyethylene , Tenebrio , Animals , Tenebrio/metabolism , Polyethylene/metabolism , Microplastics/toxicity , Gastrointestinal Microbiome/drug effects , Oxidative Stress
13.
Environ Res ; 252(Pt 1): 118810, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38552829

ABSTRACT

Nitrate/nitrite-dependent anaerobic methane oxidation (n-DAMO) process offers a promising solution for simultaneously achieving methane emissions reduction and efficient nitrogen removal in wastewater treatment. Although nitrogen removal at a practical rate has been achieved by n-DAMO biofilm process, the mechanisms of biofilm formation and nitrogen transformation remain to be elucidated. In this study, n-DAMO biofilms were successfully developed in the membrane aerated moving bed biofilm reactor (MAMBBR) and removed nitrate at a rate of 159 mg NO3--N L-1 d-1. The obvious increase in the content of extracellular polymeric substances (EPS) indicated that EPS production was important for biofilm development. n-DAMO microorganisms dominated the microbial community, and n-DAMO bacteria were the most abundant microorganisms. However, the expression of biosynthesis genes for proteins and polysaccharides encoded by n-DAMO archaea was significantly more active compared to other microorganisms, suggesting the central role of n-DAMO archaea in EPS production and biofilm formation. In addition to nitrate reduction, n-DAMO archaea were revealed to actively express dissimilatory nitrate reduction to ammonium and nitrogen fixation. The produced ammonium was putatively converted to dinitrogen gas through the joint function of n-DAMO archaea and n-DAMO bacteria. This study revealed the biofilm formation mechanism and nitrogen-transformation network in n-DAMO biofilm systems, shedding new light on promoting the application of n-DAMO process.


Subject(s)
Biofilms , Bioreactors , Methane , Nitrates , Oxidation-Reduction , Biofilms/growth & development , Methane/metabolism , Anaerobiosis , Nitrates/metabolism , Bioreactors/microbiology , Nitrogen/metabolism , Archaea/metabolism , Archaea/genetics , Archaea/physiology , Bacteria/metabolism , Bacteria/genetics , Waste Disposal, Fluid/methods
14.
J Hazard Mater ; 465: 133446, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38219578

ABSTRACT

Polyethylene terephthalate (PET or polyester) is a commonly used plastic and also contributes to the majority of plastic wastes. Mealworms (Tenebrio molitor larvae) are capable of biodegrading major plastic polymers but their degrading ability for PET has not been characterized based on polymer chain size molecular size, gut microbiome, metabolome and transcriptome. We verified biodegradation of commercial PET by T. molitor larvae in a previous report. Here, we reported that biodegradation of commercial PET (Mw 29.43 kDa) was further confirmed by using the δ13C signature as an indication of bioreaction, which was increased from - 27.50‰ to - 26.05‰. Under antibiotic suppression of gut microbes, the PET was still depolymerized, indicating that the host digestive enzymes could degrade PET independently. Biodegradation of high purity PET with low, medium, and high molecular weights (MW), i.e., Mw values of 1.10, 27.10, and 63.50 kDa with crystallinity 53.66%, 33.43%, and 4.25%, respectively, showed a mass reduction of > 95%, 86%, and 74% via broad depolymerization. Microbiome analyses indicated that PET diets shifted gut microbiota to three distinct structures, depending on the low, medium, and high MW. Metagenome sequencing, transcriptomic, and metabolic analyses indicated symbiotic biodegradation of PET by the host and gut microbiota. After PET was fed, the host's genes encoding degradation enzymes were upregulated, including genes encoding oxidizing, hydrolyzing, and non-specific CYP450 enzymes. Gut bacterial genes for biodegrading intermediates and nitrogen fixation also upregulated. The multiple-functional metabolic pathways for PET biodegradation ensured rapid biodegradation resulting in a half-life of PET less than 4 h with less negative impact by PET MW and crystallinity.


Subject(s)
Tenebrio , Animals , Tenebrio/metabolism , Tenebrio/microbiology , Polystyrenes/metabolism , Polyethylene Terephthalates/metabolism , Polymers , Larva/metabolism , Polyethylene/metabolism , Plastics/metabolism , Biodegradation, Environmental , Metabolome
15.
Water Res ; 249: 120915, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38029487

ABSTRACT

Utilizing H2-assisted ex-situ biogas upgrading and acetate recovery holds great promise for achieving high value utilization of biogas. However, it faces a significant challenge due to acetate's high solubility and limited economic value. To address this challenge, we propose an innovative strategy for simultaneous upgrading of biogas and the production of medium-chain fatty acids (MCFAs). A series of batch tests evaluated the strategy's efficiency under varying initial gas ratios (v/v) of H2, CH4, CO2, along with varying ethanol concentrations. The results identified the optimal conditions as initial gas ratios of 3H2:3CH4:2CO2 and an ethanol concentration of 241.2 mmol L-1, leading to maximum CH4 purity (97.2 %), MCFAs yield (54.2 ± 2.1 mmol L-1), and MCFAs carbon-flow distribution (62.3 %). Additionally, an analysis of the microbial community's response to varying conditions highlighted the crucial roles played by microorganisms such as Clostridium, Proteiniphilum, Sporanaerobacter, and Bacteroides in synergistically assimilating H2 and CO2 for MCFAs production. Furthermore, a 160-day continuous operation using a dual-membrane aerated biofilm reactor (dMBfR) was conducted. Remarkable achievements were made at a hydraulic retention time of 2 days, including an upgraded CH4 content of 96.4 ± 0.3 %, ethanol utilization ratio (URethanol) of 95.7 %, MCFAs production rate of 28.8 ± 0.3 mmol L-1 d-1, and MCFAs carbon-flow distribution of 70 ± 0.8 %. This enhancement is proved to be an efficient in biogas upgrading and MCFAs production. These results lay the foundation for maximizing the value of biogas, reducing CO2 emissions, and providing valuable insights into resource recovery.


Subject(s)
Biofuels , Bioreactors , Carbon Dioxide , Methane , Biofilms , Acetates , Carbon , Ethanol , Fatty Acids
16.
Bioresour Technol ; 394: 130236, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38142912

ABSTRACT

The conversion of carbon dioxide (CO2) from biogas into medium-chain fatty acids (MCFAs) represents an eco-friendly resource recovery approach to reduce dependence on fossil fuels and combat global climate change. This study presented the novel concept of integrated resource recovery by coupling biogas upgrading and MCFAs production for the first time. Initially, the impact of different initial ethanol concentrations on chain elongation was examined, determining that an ethanol concentration of 160 mmol/L maximized MCFAs yield at 45.7 mmol/L. Subsequently, using this optimal ethanol supply, the integrated strategy was implemented by connecting two bioreactors in series and maintaining continuous operation for 160-day. The results were noteworthy: upgraded bio-methane purity reached 97.6 %, MCFAs production rate and carbon-flow distribution reached 24.5 mmol/L d-1 and 76.1 %, respectively. In summary, these promising outcomes pioneer a resource recovery approach, enabling the high-value utilization of biogas and the conversion of CO2 into valuable bio-chemicals.


Subject(s)
Biofuels , Carbon Dioxide , Bioreactors , Fatty Acids , Methane , Ethanol
17.
Environ Sci Technol ; 57(50): 20975-20991, 2023 Dec 19.
Article in English | MEDLINE | ID: mdl-37931214

ABSTRACT

Nitrate/nitrite-dependent anaerobic oxidation of methane (n-DAMO) is a recently discovered process, which provides a sustainable perspective for simultaneous nitrogen removal and greenhouse gas emission (GHG) mitigation by using methane as an electron donor for denitrification. However, the engineering roadmap of the n-DAMO process is still unclear. This work constitutes a state-of-the-art review on the classical and most recently discovered metabolic mechanisms of the n-DAMO process. The versatile combinations of the n-DAMO process with nitrification, nitritation, and partial nitritation for nitrogen removal are also clearly presented and discussed. Additionally, the recent advances in bioreactor development are systematically reviewed and evaluated comprehensively in terms of methane supply, biomass retention, membrane requirement, startup time, reactor performance, and limitations. The key issues including enrichment and operation strategy for the scaling up of n-DAMO-based processes are also critically addressed. Moreover, the challenges inherent to implementing the n-DAMO process in practical applications, including application scenario recognition, GHG emission mitigation, and operation under realistic conditions, are highlighted. Finally, prospects as well as opportunities for future research are proposed. Overall, this review provides a roadmap for potential applications and further development of the n-DAMO process in the field of wastewater treatment.


Subject(s)
Ammonium Compounds , Nitrates , Nitrates/metabolism , Nitrites/metabolism , Nitrification , Anaerobiosis , Methane , Denitrification , Ammonium Compounds/metabolism , Oxidation-Reduction , Bioreactors , Nitrogen/metabolism
18.
Phytochemistry ; 216: 113871, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37777165

ABSTRACT

Five undescribed eudesmane sesquiterpenoids, artemilavanins A-E, and one undescribed rearranged eudesmane sesquiterpenoid, artemilavanin F, were isolated from the 95% ethanol extract of the aerial parts of Artemisia lavandulaefolia DC., along with ten known compounds. The structures and configurations of undescribed compounds were mainly elucidated by spectroscopic analyses and single-crystal X-ray diffraction analysis. Among all isolated compounds, artemilavanin F exhibited inhibitory activity on PANC-1 pancreatic cancer cells with IC50 of 9.69 ± 2.39 µM. Artemilavanin F inhibited PANC-1 cell proliferation by induction of G2/M cell cycle arrest and apoptosis mediated by downregulation of cyclin-dependent kinases and accumulation of reactive oxygen species. Moreover, artemilavanin F inhibited the colony formation, cell migration and sphere formation of PANC-1 cells, indicating the suppression of stem-cell-like phenotype of PANC-1 cells. Further results confirmed that the expression of cancer stem cell markers such as Bmi1, CD44, CD133 were inhibited by artemilavanin F. Downregulation of epithelial-mesenchymal transition (EMT) markers such as N-cadherin and Oct-4 indicated the potential of artemilavanin F in prevention of metastasis.


Subject(s)
Artemisia , Pancreatic Neoplasms , Sesquiterpenes, Eudesmane , Sesquiterpenes , Artemisia/chemistry , Pancreatic Neoplasms/drug therapy , Sesquiterpenes, Eudesmane/pharmacology , Sesquiterpenes, Eudesmane/analysis , Sesquiterpenes, Eudesmane/chemistry , Plant Components, Aerial/chemistry , Sesquiterpenes/chemistry , Molecular Structure , Pancreatic Neoplasms
19.
World J Clin Cases ; 11(26): 6159-6164, 2023 Sep 16.
Article in English | MEDLINE | ID: mdl-37731564

ABSTRACT

BACKGROUND: Villous adenoma is a rare tumor in the urinary system that usually occurs in the bladder. It is extremely uncommon in the renal pelvis. Most of the previously reported cases have been diagnosed with severe hydronephrosis associated with renal parenchyma atrophy prior to surgery. Because of its rarity, available information on the pathogenesis, diagnosis, treatment and prognosis of the disease is limited. We reported a case of kidney stones with hydronephrosis. During percutaneous nephroscopic lithotripsy, a renal pelvis tumor was found. Biopsy confirmed that the tumor was a villous adenoma of the renal pelvis. CASE SUMMARY: A 68-year-old female was admitted to the hospital due to right kidney stones with right hydronephrosis. After admission, a urinary system plain computed tomography scan was performed, which revealed right kidney stones with right hydronephrosis and right upper ureteral dilatation. Multiple new cauliflower-like papillary masses were then discovered in the renal pelvis and calyces during right percutaneous nephroscopic lithotripsy. Biopsy results indicated villous adenoma with high-grade glandular intraepithelial neoplasia. The patient underwent laparoscopic radical resection of the right kidney and ureter. Based on histopathological and immunohistochemical examination, the patient was diagnosed with villous adenoma without adenocarcinoma. CONCLUSION: Villous adenoma is rare in the urinary system. We reported a case of renal pelvis villous adenoma, which may provide useful information for the early diagnosis and treatment of this tumor.

20.
Sci Total Environ ; 905: 167142, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-37722432

ABSTRACT

Old-fashioned wastewater treatments for nitrogen depend on heterotrophic denitrification process. It would utilize extra organic carbon source as electron donors when the C/N of domestic wastewater was too low to ensure heterotrophic denitrification process. It would lead to non-compliance with carbon reduction targets and impose an economic burden on wastewater treatment. Denitrifying anaerobic methane oxidation (DAMO), which could utilize methane serving as electron donors to replace traditional organic carbon (methanol or sodium acetate), supplies a novel approach for wastewater treatment. As the primary component of biogas, methane is an inexpensive carbon source. With anaerobic digestion becoming increasingly popular for sludge reduction in wastewater treatment plants (WWTPs), efficient biogas utilization through DAMO can offer an environmentally friendly option for in-situ biogas recycling. Here, we reviewed the metabolic principle and relevant research for DAMO and biogas recycling utilization, outlining the prospect of employing DAMO for wastewater treatment and biogas recycling utilization in WWTPs. The application of DAMO provides a new focal point for enhancing efficiency and sustainability in WWTPs.


Subject(s)
Ammonium Compounds , Water Purification , Humans , Wastewater , Biofuels , Methane/metabolism , Anaerobiosis , Denitrification , Oxidation-Reduction , Bioreactors , Nitrogen/metabolism , Carbon , Nitrites , Ammonium Compounds/metabolism
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