scholarly journals Differences in the Effects of Calcium and Magnesium Ions on the Anammox Granular Properties to Alleviate Salinity Stress

2021 ◽  
Vol 12 (1) ◽  
pp. 19
Author(s):  
Yeonju Kim ◽  
Jaecheul Yu ◽  
Soyeon Jeong ◽  
Jeongmi Kim ◽  
Seongjae Park ◽  
...  
Keyword(s):  
Salinity Stress ◽  
Divalent Cations ◽  
Optimum Concentration ◽  
Anammox Bacteria ◽  
Saline Wastewater ◽  
Original Activity ◽  
Anammox Activity ◽  
Significant Difference ◽  
Anammox Process ◽  
Calcium And Magnesium Ions

Divalent cations were known to alleviate salinity stress on anammox bacteria. Understanding the mechanism of reducing the salinity stress on anammox granules is essential for the application of the anammox process for saline wastewater treatment. In this study, the effect of Ca2+ and Mg2+ augmentation on the recovery of the activity of freshwater anammox granules affected by salinity stress was evaluated. At the condition of a salinity stress of 5 g NaCl/L, the specific anammox activity (SAA) of the granule decreased to 50% of that of the SAA without NaCl treatment. Augmentation of Ca2+ at the optimum concentration of 200 mg/L increased the SAA up to 78% of the original activity, while the augmentation of Mg2+ at the optimum concentration of 70 mg/L increased the SAA up to 71%. EPS production in the granules was increased by the augmentation of divalent cations compared with the granules affected by salinity stress. In the soluble EPS, the ratio of protein to polysaccharides was higher in the granules augmented by Ca2+ than with Mg2+, and the functional groups of the EPS differed from each other. The amount of Na+ sequestered in the soluble EPS was increased by the augmentation of divalent cations, which seems to contribute to the alleviation of salinity stress. Ca. Kuenenia-like anammox bacteria, which were known to be salinity stress-tolerant, were predominant in the granules and there was no significant difference in the microbial community of the granules by the salinity stress treatment. Our results suggest that the alleviation effect of the divalent cations on the salinity stress on the anammox granules might be associated with the increased production of different EPS rather than in changes to the anammox bacteria.

The short- and long-term inhibitory effects of Fe (II) on anaerobic ammonium oxidizing (anammox) process

2019 ◽  
Vol 79 (10) ◽  
pp. 1860-1867 ◽  
Author(s):  
Cherh Yih Mak ◽  
Jih Gaw Lin ◽  
Wen Hsing Chen ◽  
Choon Aun Ng ◽  
Mohammed J. K. Bashir
Keyword(s):  
Quantitative Polymerase Chain Reaction ◽  
Substrate Inhibition ◽  
Optimum Concentration ◽  
Anammox Bacteria ◽  
Batch Test ◽  
Short Term ◽  
Anammox Activity ◽  
Study Results ◽  
Anammox Process

Abstract The application of the anammox process has great potential in treating nitrogen-rich wastewater. The presence of Fe (II) is expected to affect the growth and activity of anammox bacteria. Short-term (acute) and long-term effects (chronic) of Fe (II) on anammox activity were investigated. In the short-term study, results demonstrated that the optimum concentration of Fe (II) that could be added to anammox is 0.08 mM, at which specific anammox activity (SAA) improved by 60% compared to the control assay, 0.00 mM. The inhibition concentration, IC50, of Fe (II) was found to be 0.192 mM. Kinetics of anammox specific growth rate were estimated based on results of the batch test and evaluated with Han-Levenspiel's substrate inhibition kinetics model. The optimum concentration and IC50 of Fe (II) predicted by the Han-Levenspiel model was similar to the batch test, with values of 0.07 mM and 0.20 mM, respectively. The long-term effect of Fe (II) on the performance of a sequencing batch reactor (SBR) was evaluated. Results showed that an appropriate Fe (II) addition enhanced anammox activity, achieving 85% NH4+-N and 96% NO2−-N removal efficiency when 0.08 mM of Fe (II) was added. Quantitative polymerase chain reaction (qPCR) was adopted to detect and identify the anammox bacteria.

scholarly journals Short- and long-term orange dye effects on ammonium oxidizing and anammox bacteria activities

2017 ◽  
Vol 76 (1) ◽  
pp. 79-86 ◽  
Author(s):  
A. Val del Río ◽  
A. Stachurski ◽  
R. Méndez ◽  
J. L. Campos ◽  
J. Surmacz-Górska ◽  
...  
Keyword(s):  
Azo Dye ◽  
Specific Activity ◽  
Dye Adsorption ◽  
Anammox Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Continuous Stirred Tank Reactor ◽  
Partial Nitritation ◽  
Anammox Activity ◽  
Anammox Process

The effects of orange azo dye over ammonia oxidizing bacteria (AOB) and anammox bacteria activities were tested. Performed batch tests indicated that concentrations lower than 650 mgorange/L stimulated AOB activity, while anammox bacteria activity was inhibited at concentrations higher than 25 mgorange/L. Long-term performance of a continuous stirred tank reactor (CSTR) for the partial nitritation and a sequencing batch reactor (SBR) for the anammox process was tested in the presence of 50 mgorange/L. In the case of the partial nitritation process, both the biomass concentration and the specific AOB activity increased after 50 days of orange azo dye addition. Regarding the anammox process, specific activity decreased down to 58% after 12 days of operation with continuous feeding of 50 mgorange/L. However, the anammox activity was completely recovered only 54 days after stopping the dye addition in the feeding. Once the biomass was saturated the azo dye adsorption onto the biomass was insignificant in the CSTR for the partial nitritation process fed with 50 mgorange/L. However, in the SBR the absorption was determined as 6.4 mgorange/g volatile suspended solids. No biological decolorization was observed in both processes.

scholarly journals Start-Up of Anammox SBR from Non-Specific Inoculum and Process Acceleration Methods by Hydrazine

Water ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 350
Author(s):  
Ivar Zekker ◽  
Oleg Artemchuk ◽  
Ergo Rikmann ◽  
Kelvin Ohimai ◽  
Gourav Dhar Bhowmick ◽  
...  
Keyword(s):  
Nitrogen Removal ◽  
Biological Nutrient Removal ◽  
Anaerobic Sludge ◽  
Anammox Bacteria ◽  
Ammonium Oxidation ◽  
Reject Water ◽  
Start Up ◽  
Anammox Activity ◽  
Optimum Salinity ◽  
Anammox Process

Biological nutrient removal from wastewater to reach acceptable levels is needed to protect water resources and avoid eutrophication. The start-up of an anaerobic ammonium oxidation (anammox) process from scratch was investigated in a 20 L sequence batch reactor (SBR) inoculated with a mixture of aerobic and anaerobic sludge at 30 ± 0.5 °C with a hydraulic retention time (HRT) of 2–3 days. The use of NH4Cl, NaNO2, and reject water as nitrogen sources created different salinity periods, in which the anammox process performance was assessed: low (<0.2 g of Cl−/L), high (18.2 g of Cl−/L), or optimum salinity (0.5–2 g of Cl−/L). Reject water feeding gave the optimum salinity, with an average nitrogen removal efficiency of 80%, and a TNRR of 0.08 kg N/m3/d being achieved after 193 days. The main aim was to show the effect of a hydrazine addition on the specific anammox activity (SAA) and denitrification activity in the start-up process to boost the autotrophic nitrogen removal from scratch. The effect of the anammox intermediate hydrazine addition was tested to assess its concentration effect (range of 2–12.5 mg of N2H4/L) on diminishing denitrifier activity and accelerating anammox activity at the same time. Heterotrophic denitrifiers’ activity was diminished by all hydrazine additions compared to the control; 5 mg of N2H4/L added enhanced SAA compared to the control, achieving an SAA of 0.72 (±0.01) mg N/g MLSS/h, while the test with 7.5 mg of N2H4/L reached the highest overall SAA of 0.98 (±0.09) mg N g/MLSS/h. The addition of trace amounts of hydrazine for 6 h was also able to enhance SAA after inhibition by organic carbon source sodium acetate addition at a high C/N ratio of 10/1. The start-up of anammox bacteria from the aerobic–anaerobic suspended biomass was successful, with hydrazine significantly accelerating anammox activity and decreasing denitrifier activity, making the method applicable for side-stream as well as mainstream treatment.

scholarly journals Potential Contribution of Anammox to Nitrogen Loss from Paddy Soils in Southern China

2014 ◽  
Vol 81 (3) ◽  
pp. 938-947 ◽  
Author(s):  
Xiao-Ru Yang ◽  
Hu Li ◽  
San-An Nie ◽  
Jian-Qiang Su ◽  
Bo-Sen Weng ◽  
...  
Keyword(s):  
Southern China ◽  
Nitrogen Loss ◽  
Terrestrial Ecosystems ◽  
Dry Weight ◽  
Paddy Soils ◽  
Anammox Bacteria ◽  
Potential Contribution ◽  
Content Type ◽  
Anammox Activity ◽  
Anammox Process

ABSTRACTThe anaerobic oxidation of ammonium (anammox) process has been observed in diverse terrestrial ecosystems, while the contribution of anammox to N2production in paddy soils is not well documented. In this study, the anammox activity and the abundance and diversity of anammox bacteria were investigated to assess the anammox potential of 12 typical paddy soils collected in southern China. Anammox bacteria related to “CandidatusBrocadia” and “CandidatusKuenenia” and two novel unidentified clusters were detected, with “CandidatusBrocadia” comprising 50% of the anammox population. The prevalence of the anammox was confirmed by the quantitative PCR results based on hydrazine synthase (hzsB) genes, which showed that the abundance ranged from 1.16 × 104to 9.65 × 104copies per gram of dry weight. The anammox rates measured by the isotope-pairing technique ranged from 0.27 to 5.25 nmol N per gram of soil per hour in these paddy soils, which contributed 0.6 to 15% to soil N2production. It is estimated that a total loss of 2.50 × 106Mg N per year is linked to anammox in the paddy fields in southern China, which implied that ca. 10% of the applied ammonia fertilizers is lost via the anammox process. Anammox activity was significantly correlated with the abundance ofhzsBgenes, soil nitrate concentration, and C/N ratio. Additionally, ammonia concentration and pH were found to be significantly correlated with the anammox bacterial structure.

Inhibition effect of swine wastewater heavy metals and antibiotics on anammox activity

2012 ◽  
Vol 66 (7) ◽  
pp. 1519-1526 ◽  
Author(s):  
T. Lotti ◽  
M. Cordola ◽  
R. Kleerebezem ◽  
S. Caffaz ◽  
C. Lubello ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Prolonged Exposure ◽  
Liquid Fraction ◽  
Swine Manure ◽  
Swine Wastewater ◽  
Anammox Bacteria ◽  
Ammonium Oxidation ◽  
Batch Tests ◽  
Anammox Activity ◽  
Anammox Process

The feasibility of anaerobic ammonium oxidation (anammox) process to treat wastewaters containing antibiotics and heavy metals (such as the liquid fraction of the anaerobically digested swine manure) was studied in this work. The specific anammox activity (SAA) was evaluated by means of manometric batch tests. The effects of oxytetracycline, sulfathiazole, copper and zinc were studied. The experimental data of the short-term assays were fitted with an inhibition model to identify the half maximal inhibitory concentration (IC50). After 24 h exposures, IC50-values equal to 1.9, 3.9, 650 and 1,100 mg L−1 were identified for copper, zinc, sulfathiazole and tetracycline respectively. The effect of prolonged exposure (14 days) to oxytetracycline and sulfathiazole was studied by means of repeated batch-assays. Anabolism and catabolism reactions were active during the inhibition tests indicating that anammox bacteria could grow even in the extreme conditions tested. Considering the average concentrations expected in swine wastewaters, the inhibitors studied do not seem to represent a problem for the application of the anammox process. However, in order to verify the effect of these compounds on the growth of anammox bacteria, continuous culture experiments could be conducted.

scholarly journals Transcriptomic Analysis of Rice Plants Overexpressing PsGAPDH in Response to Salinity Stress

Genes ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 641
Author(s):  
Hyemin Lim ◽  
Hyunju Hwang ◽  
Taelim Kim ◽  
Soyoung Kim ◽  
Hoyong Chung ◽  
...  
Keyword(s):  
Salt Stress ◽  
Abiotic Stress ◽  
Salinity Stress ◽  
Functional Enrichment ◽  
Differentially Expressed ◽  
Pathway Enrichment Analysis ◽  
Sequencing Data ◽  
Illumina Hiseq ◽  
Rice Plants ◽  
Significant Difference

In plants, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is a main enzyme in the glycolytic pathway. It plays an essential role in glycerolipid metabolism and response to various stresses. To examine the function of PsGAPDH (Pleurotus sajor-caju GAPDH) in response to abiotic stress, we generated transgenic rice plants with single-copy/intergenic/homozygous overexpression PsGAPDH (PsGAPDH-OX) and investigated their responses to salinity stress. Seedling growth and germination rates of PsGAPDH-OX were significantly increased under salt stress conditions compared to those of the wild type. To elucidate the role of PsGAPDH-OX in salt stress tolerance of rice, an Illumina HiSeq 2000 platform was used to analyze transcriptome profiles of leaves under salt stress. Analysis results of sequencing data showed that 1124 transcripts were differentially expressed. Using the list of differentially expressed genes (DEGs), functional enrichment analyses of DEGs such as Gene Ontology (GO) terms and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were performed. KEGG pathway enrichment analysis revealed that unigenes exhibiting differential expression were involved in starch and sucrose metabolism. Interestingly, trehalose-6-phosphate synthase (TPS) genes, of which expression was enhanced by abiotic stress, showed a significant difference in PsGAPDH-OX. Findings of this study suggest that PsGAPDH plays a role in the adaptation of rice plants to salt stress.

Protection of Italian ryegrass (Lolium multiflorum L.) seedlings from salinity stress following seed priming with L-methionine and casein hydrolysate

2020 ◽  
pp. 1-9
Author(s):  
Keum-Ah Lee ◽  
Youngnam Kim ◽  
Hossein Alizadeh ◽  
David W.M. Leung
Keyword(s):  
Oxidative Stress ◽  
Amino Acids ◽  
Salinity Stress ◽  
Lolium Multiflorum ◽  
Casein Hydrolysate ◽  
Seed Priming ◽  
Germination Percentage ◽  
Italian Ryegrass ◽  
Significant Difference ◽  
Protein Amino Acids

Abstract Seed priming with water (hydropriming or HP) has been shown to be beneficial for seed germination and plant growth. However, there is little information on the effects of seed priming with amino acids and casein hydrolysate (CH) compared with HP, particularly in relation to early post-germinative seedling growth under salinity stress. In this study, Italian ryegrass seeds (Lolium multiflorum L.) were primed with 1 mM of each of the 20 protein amino acids and CH (200 mg l−1) before they were germinated in 0, 60 and 90 mM NaCl in Petri dishes for 4 d in darkness. Germination percentage (GP), radicle length (RL) and peroxidase (POD) activity in the root of 4-d-old Italian ryegrass seedlings were investigated. Generally, when the seeds were germinated in 0, 60 and 90 mM NaCl, there was no significant difference in GP of seeds among various priming treatments, except that a higher GP was observed in seeds of HP treatment compared with the non-primed seeds when incubated in 60 mM NaCl. When incubated in 60 and 90 mM NaCl, seedlings from seeds primed with L-methionine or CH exhibited greater RL (greater protection against salinity stress) and higher root POD activity than those from non-primed and hydro-primed seeds. Under salinity stress, there were higher levels of malondialdehyde (MDA) in the root of 4-d-old Italian ryegrass seedlings, a marker of oxidative stress, but seed priming with CH was effective in reducing the salinity-triggered increase in MDA content. These results suggest that priming with L-methionine or CH would be better than HP for the protection of seedling root growth under salinity stress and might be associated with enhanced antioxidative defence against salinity-induced oxidative stress.

scholarly journals Temperature modulates stress response in anammox reactors

2020 ◽  
Author(s):  
Robert Niederdorfer ◽  
Damian Hausherr ◽  
Alejandro Palomo ◽  
Jing Wei ◽  
Paul Magyar ◽  
...  
Keyword(s):  
Stress Response ◽  
Dissolved Oxygen ◽  
Nitrogen Removal ◽  
High Stress ◽  
Anammox Bacteria ◽  
Transcriptional Responses ◽  
Microbial Biofilms ◽  
Temperature Regimes ◽  
Anammox Activity ◽  
Stress Susceptibility

AbstractAutotrophic nitrogen removal by anaerobic ammonium oxidizing (anammox) bacteria is an energy-efficient nitrogen removal process in wastewater treatment. However, full-scale deployment under mainstream conditions remains challenging for practitioners due to the high stress susceptibility of anammox bacteria towards fluctuations in dissolved oxygen and temperature. Here, we investigated the response of microbial biofilms with verified anammox activity to oxygen shocks under favorable and cold temperature regimes. Genome-centric metagenomics and metatranscriptomics were used to investigate the stress response on various biological levels. We show that temperature regime and strength of oxygen perturbations induced divergent responses from the process level down to the transcriptional profile of individual taxa. Temperature induced distinct transcriptional states in compositionally identical communities and transient pulses of dissolved oxygen resulted in the upregulation of stress-response only under favorable temperatures. Anammox species and other key biofilm taxa display different transcriptional responses to the induced stress regimes.

Performance and inhibition recovery of anammox reactors seeded with different types of sludge

2011 ◽  
Vol 63 (4) ◽  
pp. 710-718 ◽  
Author(s):  
S. Q. Ni ◽  
J. Meng
Keyword(s):  
Nitrogen Removal ◽  
Granular Sludge ◽  
Recovery Process ◽  
Nitrogen Loading ◽  
Anaerobic Sludge ◽  
Anammox Bacteria ◽  
Recovery Processes ◽  
Anammox Activity ◽  
Different Types ◽  
Anaerobic Sludge Blanket

In order to study the performance, inhibition and recovery processes of different types of anammox sludge, three up-flow anaerobic sludge blanket reactors were inoculated with flocculent sludge, granular sludge, and cultured inactive methanogenic granules. During stable period, with nitrogen loading rates of 0.9–1.1 kg/m3/d, the total nitrogen removal efficiencies of these reactors averaged at 86.5%, 90.8% and 93.5%, respectively. The kinetics study indicated that the reactor seeded with cultured inactive methanogenic granules possessed the highest nitrogen removal potential, followed by the granular anammox reactor and the flocculent anammox reactor. The study suggested that a concentration as high as 988.3 mg NH4+-N/L and 484.4 mg NO2−-N/L could totally inhibit granular anammox bacteria and result in a inhibition of 50% flocculent anammox activity. In addition, reactors seeded with flocculent sludge and anammox granules could be fully recovered by decreasing their influent substrate concentrations. However, the decrease of influent substrate concentration for the reactor with cultured inactive methanogenic granules could only restore about 75% of its bacterial activity. In this study, anammox bacteria purity was the major factor to evaluate the recovery ability in comparison with sludge type. Free ammonia was a more appropriate indicator for the anammox recovery process compared to free nitric acid.

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