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Environmental Research Mar 2023In order to solve nitrogen pollution in environmental water, two heterotrophic nitrifying and aerobic denitrifying strains isolated from acid paddy soil were identified...
In order to solve nitrogen pollution in environmental water, two heterotrophic nitrifying and aerobic denitrifying strains isolated from acid paddy soil were identified as Achromobacter sp. strain HNDS-1 and Enterobacter sp. strain HNDS-6 respectively. Strain HNDS-1 and strain HNDS-6 exhibited amazing ability to nitrogen removal. When (NH)SO, KNO, NaNO were used as nitrogen resource respectively, the NH-N, NO-N, NO-N removal efficiencies of strain HNDS-1 were 93.31%, 89.47%, and 100% respectively, while those of strain HNDS-6 were 82.39%, 96.92%, and 100%. And both of them could remove mixed nitrogen effectively in low C/N (C/N = 5). Strain HNDS-1 could remove 76.86% NH-N and 75.13% NO-N. And strain HNDS-6 can remove 65.07% NH-N and 78.21% NO-N. A putative ammonia monooxygenase, nitrite reductase, nitrate reductase, assimilatory nitrate reductase, nitrate/nitrite transport protein and nitric oxide reductase of strain HNDS-1, while hydroxylamine reductase, nitrite reductase, nitrate reductase, assimilatory nitrate reductase, nitrate/nitrite transport protein, and nitric oxide reductase of strain HNDS-6 were identified by genomic analysis. DNA-SIP analysis showed that genes Nxr, narG, nirK, norB, nosZ were involved in nitrogen removal pathway, which indicates that the denitrification pathway of strain HNDS-1 and strain HNDS-6 was NO→NO→NO→NO→N during NH-N removal process. And the nitrification pathway of strain HNDS-1 and strain HNDS-6 was NO→NO, but the nitrification pathway of NH→ NO needs further studies.
Topics: Achromobacter; Aerobiosis; Denitrification; Enterobacter; Nitrates; Nitrification; Nitrite Reductases; Nitrites; Nitrogen; Nitrogen Dioxide
PubMed: 36621544
DOI: 10.1016/j.envres.2023.115240 -
Environmental Research Aug 2023Nitrogen (N) and phosphorous (P) removal by a single bacterium could improve the biological reaction efficiency and reduce the operating cost and complexity in...
Nitrogen (N) and phosphorous (P) removal by a single bacterium could improve the biological reaction efficiency and reduce the operating cost and complexity in wastewater treatment plants (WWTPs). Here, an isolated strain was identified as Pseudomonas mendocina SCZ-2 and showed high performance of heterotrophic nitrification (HN) and aerobic denitrification (AD) without intermediate accumulation. During the AD process, the nitrate removal efficiency and rate reached a maximum of 100% and 47.70 mg/L/h, respectively, under optimal conditions of sodium citrate as carbon source, a carbon-to-nitrogen ratio of 10, a temperature of 35 °C, and shaking a speed of 200 rpm. Most importantly, the strain SCZ-2 could rapidly and simultaneously eliminate N and P with maximum NH-N, NO-N, NO-N, and PO-P removal rates of 14.38, 17.77, 20.13 mg N/L/h, and 2.93 mg P/L/h, respectively. Both the N and P degradation curves matched well with the modified Gompertz model. Moreover, the amplification results of functional genes, whole genome sequencing, and enzyme activity tests provided theoretical support for simultaneous N and P removal pathways. This study deepens our understanding of the role of HN-AD bacteria and provides more options for simultaneous N and P removal from actual sewage.
Topics: Denitrification; Pseudomonas mendocina; Nitrogen; Aerobiosis; Nitrification; Phosphorus; Carbon; Nitrites
PubMed: 37149028
DOI: 10.1016/j.envres.2023.116062 -
Journal of Applied Microbiology Jan 2023To analyze the effect of a prothioconazole- and tebuconazole-based fungicide on the yield and silage characteristics of whole-crop corn (WCC) and high-moisture ear corn...
Effects of a prothioconazole- and tebuconazole-based fungicide on the yield, silage characteristics, and fungal mycobiota of corn harvested and conserved as whole-crop and high-moisture ear silages.
AIMS
To analyze the effect of a prothioconazole- and tebuconazole-based fungicide on the yield and silage characteristics of whole-crop corn (WCC) and high-moisture ear corn (HMC) silages and on the fungal community dynamics from the harvest to aerobic exposure.
METHODS AND RESULTS
Corn were untreated (NT) or treated (T) with a prothioconazole- and tebuconazole-based fungicide and harvested as WCC and HMC. Silages were conserved for 60 and 160 d and subjected to an aerobic stability test. The fungicide increased the yield per hectare however, it did not affect the main nutritional characteristics of WCC or HMC. The main chemical, fermentative and microbial characteristics, dry matter (DM) losses and aerobic stability were mainly affected by the conservation time, regardless of the treatment. Fusarium, Alternaria, Aspergillus, and Penicillium genera were identified as dominant before ensiling, but Aspergillus and Penicillium became dominant after silo opening and aerobic exposure. Yeast population during ensiling and aerobic deterioration resulted in a simplification, with Pichia and Kazachstania genera being dominant.
CONCLUSIONS
The application of fungicide improved the DM, starch, and net energy for lactation (NEL) yield per hectare but had no consistent effect on the microbial and fermentative silage quality and aerobic stability.
Topics: Silage; Fungicides, Industrial; Zea mays; Fermentation; Aerobiosis
PubMed: 36724244
DOI: 10.1093/jambio/lxac033 -
Bioresource Technology May 2023The algal/bacterial biomass and extracellular polymeric substances (EPSs) existing in microalgal-bacterial aerobic granular sludge (MB-AGS) offer a promising... (Review)
Review
The algal/bacterial biomass and extracellular polymeric substances (EPSs) existing in microalgal-bacterial aerobic granular sludge (MB-AGS) offer a promising bioresource. The current review-based paper presents a systematic overview of the compositions and interactions (gene transfer, signal transduction, and nutrient exchange) of microalgal and bacteria consortia, the role of cooperative or competitive partnerships of MB-AGS in the treatment of wastewater and recovery of resource, and the environmental/operational factors affecting their interactions and EPS production. Moreover, a brief notes is given on the opportunities and major challenges of utilizing the microalgal-bacterial biomass and EPS for phosphorus and polysaccharides chemical recovery, renewable energy (i.e. biodiesel, hydrogen, electricity) production. Overall, this compact review will pave the way for developing MB-AGS future biotechnology.
Topics: Sewage; Biomass; Microalgae; Sustainable Development; Bacteria; Polymers; Bioreactors; Waste Disposal, Fluid; Aerobiosis
PubMed: 36940876
DOI: 10.1016/j.biortech.2023.128929 -
European Journal of Nutrition Sep 2020Nicotinamide riboside (NR) acts as a potent NAD precursor and improves mitochondrial oxidative capacity and mitochondrial biogenesis in several organisms. However, the...
PURPOSE
Nicotinamide riboside (NR) acts as a potent NAD precursor and improves mitochondrial oxidative capacity and mitochondrial biogenesis in several organisms. However, the effects of NR supplementation on aerobic performance remain unclear. Here, we evaluated the effects of NR supplementation on the muscle metabolism and aerobic capacity of sedentary and trained mice.
METHODS
Male C57BL/6 J mice were supplemented with NR (400 mg/Kg/day) over 5 and 10 weeks. The training protocol consisted of 5 weeks of treadmill aerobic exercise, for 60 min a day, 5 days a week. Bioinformatic and physiological assays were combined with biochemical and molecular assays to evaluate the experimental groups.
RESULTS
NR supplementation by itself did not change the aerobic performance, even though 5 weeks of NR supplementation increased NAD levels in the skeletal muscle. However, combining NR supplementation and aerobic training increased the aerobic performance compared to the trained group. This was accompanied by an increased protein content of NMNAT3, the rate-limiting enzyme for NAD + biosynthesis and mitochondrial proteins, including MTCO1 and ATP5a. Interestingly, the transcriptomic analysis using a large panel of isogenic strains of BXD mice confirmed that the Nmnat3 gene in the skeletal muscle is correlated with several mitochondrial markers and with different phenotypes related to physical exercise. Finally, NR supplementation during aerobic training markedly increased the amount of type I fibers in the skeletal muscle.
CONCLUSION
Taken together, our results indicate that NR may be an interesting strategy to improve mitochondrial metabolism and aerobic capacity.
Topics: Aerobiosis; Animals; Cell Respiration; Male; Mice; Mice, Inbred C57BL; Mitochondria; Muscle, Skeletal; NAD; Niacinamide; Pyridinium Compounds
PubMed: 31494696
DOI: 10.1007/s00394-019-02089-z -
The Science of the Total Environment Jan 2022The traditional biological nitrogen removal (BNR) follows the conventional scheme of sequential nitrification and denitrification. In recent years, novel processes such... (Review)
Review
The traditional biological nitrogen removal (BNR) follows the conventional scheme of sequential nitrification and denitrification. In recent years, novel processes such as anaerobic ammonia oxidation (anammox), complete oxidation of ammonia to nitrate in one organism (comammox), heterotrophic nitrification and aerobic denitrification (HN-AD), and dissimilatory nitrate reduction to ammonium (DNRA) are gaining tremendous attention after the discovery of metabolically versatile bacteria. Among them, HN-AD offers several advantages because individual bacteria could achieve one-stage nitrogen removal under aerobic conditions in the presence of organic carbon. In this review, besides classical BNR processes, we summarized the existing literature on HN-AD bacteria which have been isolated from diverse habitats. A particular focus was given on the diversity and physiology of HN-AD bacteria, influences of physiological and biochemical factors on their growth, nitrogen removal performances, as well as limitations and strategies in unraveling HN-AD metabolic pathways. We also presented case studies of HN-AD application in wastewater treatment facilities, pointed out forthcoming challenges of HN-AD in these systems, and presented modulation strategies for HN-AD application in engineering. This review may help improve the existing design of wastewater treatment plants by harnessing HN-AD bacteria for effective nitrogen removal.
Topics: Aerobiosis; Denitrification; Heterotrophic Processes; Nitrification; Nitrogen; Wastewater; Water Purification
PubMed: 34536867
DOI: 10.1016/j.scitotenv.2021.150212 -
Bioresource Technology Nov 2021The study aimed to isolate a novel strain with heterotrophic nitrification and aerobic denitrification ability and evaluate the nitrogen removal characteristics. Results...
The study aimed to isolate a novel strain with heterotrophic nitrification and aerobic denitrification ability and evaluate the nitrogen removal characteristics. Results showed that Ochrobactrum anthropi HND19 could remove approximately 98.6% of NH-N (104.3 mg·L) and 97.6% of NO-N (98.6 mg·L), and the removal rates achieved 4.28 and 4.01 mg-N/(L·h) by heterotrophic nitrification and aerobic denitrification. The optimal incubate conditions of strain HND19 were 120 rpm (shaking speed), 5 ‰ (salinity), 30 °C (temperature), 7.5 (C/N ratio) with sodium acetate as carbon resource. And the removal efficiency of the total nitrogen (TN) realized 73.4% under the optimal conditions. Functional genes (hao, napA, nirK, norB, and nosZ) involved in the nitrogen removal processes were successfully amplified from strain HND19. These findings indicate that the strain HND19 possesses great application feasibility in treating wastewater with high-intensity nitrogen.
Topics: Aerobiosis; Denitrification; Heterotrophic Processes; Nitrification; Nitrites; Nitrogen; Ochrobactrum anthropi
PubMed: 34332445
DOI: 10.1016/j.biortech.2021.125582 -
The Science of the Total Environment Mar 2021Phosphorus (P) and nitrogen (N) pollution are the worldwide challenging problem. In the present study, a new salt-tolerant phosphate-accumulating organism (PAO) was...
Simultaneous aerobic removal of phosphorus and nitrogen by a novel salt-tolerant phosphate-accumulating organism and the application potential in treatment of domestic sewage and aquaculture sewage.
Phosphorus (P) and nitrogen (N) pollution are the worldwide challenging problem. In the present study, a new salt-tolerant phosphate-accumulating organism (PAO) was isolated and identified as Bacillus subtilis GHSP10. Strain GHSP10 did not produce hemolysin and showed high susceptibility to antibiotics. The favorable phosphorus removal C/N ratios, P/N ratios, temperature, salinities, pH values and shaking speeds of strain GHSP10 were 10-20, 0.1-0.2, 28 °C, 0-3%, 7.5-8.5 and 100-250 r/min. Besides, strain GHSP10 could conduct heterotrophic nitrification-aerobic denitrification and the maximal removal efficiencies of ammonium, nitrite and nitrate were 99.52%, 81.10% and 95.84% respectively. Moreover, the phosphorus removal process of strain GHSP10 was achieved under entirely aerobic conditions, and glycogen and poly-β-hydroxybutyrate could provide energy source for the phosphorus removal process of strain GHSP10. The amplification of ppk, hao, napA, narG, nirK genes as well as the expression of polyphosphate kinase helped to reveal the removal pathways of phosphorus and nitrogen, providing theoretical support for the phosphorus removal, nitrification and aerobic denitrification abilities of strain GHSP10. Furthermore, efficient removal of phosphorus and nitrogen from both domestic sewage and aquaculture sewage could be accomplished by strain GHSP10. This study may provide a hopeful candidate strain for simultaneous removal of phosphorus and nitrogen pollution from both freshwater sewage and saline sewage.
Topics: Aerobiosis; Aquaculture; Bioreactors; Denitrification; Nitrification; Nitrites; Nitrogen; Phosphates; Phosphorus; Sewage
PubMed: 33223174
DOI: 10.1016/j.scitotenv.2020.143580 -
Journal of Environmental Management Jul 2023The high-efficiency and additionally economic benefits generated from aerobic granular sludge (AGS) wastewater treatment have led to its increasing popularity among... (Review)
Review
The high-efficiency and additionally economic benefits generated from aerobic granular sludge (AGS) wastewater treatment have led to its increasing popularity among academics and industrial players. The AGS process can recycle high value-added biomaterials including extracellular polymeric substances (EPS), sodium alginate-like external polymer (ALE), polyhydroxyfatty acid (PHA), and phosphorus (P), etc., which can serve various fields including agriculture, construction, and chemical while removing pollutants from wastewaters. The effects of various key operation parameters on formation and structural stability of AGS are comprehensively summarized. The degradable metabolism of typical pollutants and corresponding microbial diversity and succession in the AGS wastewater treatment system are also discussed, especially with a focus on emerging contaminants removal. In addition, recent attempts for potentially effective production of high value-added biomaterials from AGS are proposed, particularly concerning improving the yield, quality, and application of these biomaterials. This review aims to provide a reference for in-depth research on the AGS process, suggesting a new alternative for wastewater treatment recycling.
Topics: Wastewater; Sewage; Waste Disposal, Fluid; Aerobiosis; Bioreactors
PubMed: 37004484
DOI: 10.1016/j.jenvman.2023.117771 -
Methods in Molecular Biology (Clifton,... 2021Developments in mass spectrometry have made it possible to identify individual biomolecules in complex samples. This has led to advances in the detection and...
Developments in mass spectrometry have made it possible to identify individual biomolecules in complex samples. This has led to advances in the detection and quantification of both extracellular and intracellular metabolites, such as amino acids, organic acids, fatty acids, nucleotides, and CoA-esters from growth media and cellular extracts. However, the reproducibility of metabolite data can be problematic if the concentrations and/or stability of metabolites fluctuate during culture harvesting and processing. Herein we describe a standardized and efficient collection protocol and best practices for preservation and harvesting of Staphylococcus aureus cellular and supernatant samples to improve reproducibility, reliability, and consistency in mass-spectrometry-based metabolite data sets.
Topics: Aerobiosis; Guidelines as Topic; Mass Spectrometry; Metabolomics; Staphylococcus aureus
PubMed: 34264466
DOI: 10.1007/978-1-0716-1550-8_13