scholarly journals Nitrogen Removal in Oligotrophic Reservoir Water by a Mixed Aerobic Denitrifying Consortium: Influencing Factors and Immobilization Effects

2019 ◽  
Vol 16 (4) ◽  
pp. 583 ◽  
Author(s):  
Hanyue Wang ◽  
Tong Wang ◽  
Shangye Yang ◽  
Xueqing Liu ◽  
Liqing Kou ◽  
...  
Keyword(s):  
Carbon Source ◽  
Simultaneous Removal ◽  
Source Water ◽  
Reservoir Water ◽  
Carbon And Nitrogen ◽  
Initial Carbon ◽  
Oligotrophic Water ◽  
Lower Temperature ◽  
Significant Attention ◽  
Immobilized Consortium

Nitrogen pollution in reservoirs has received increasing attention in recent years. Although a number of aerobic denitrifying strains have been isolated to remove nitrogen from eutrophic waters, the situation in oligotrophic water environments has not received significant attention. In this study, a mixed aerobic denitrifying consortium screened from reservoir samples was used to remove nitrogen in an oligotrophic denitrification medium and actual oligotrophic source water. The results showed that the consortium removed 75.32% of nitrate (NO3−-N) and 63.11% of the total nitrogen (TN) in oligotrophic reservoir water during a 24-h aerobic cultivation. More initial carbon source was helpful for simultaneous removal of carbon and nitrogen in the reservoir source water. NO3−-N and TN were still reduced by 60.93% and 46.56% at a lower temperature (10 °C), respectively, though the rates were reduced. Moreover, adding phosphorus promoted bacterial growth and increased TN removal efficiency by around 20%. The performance of the immobilized consortium in source water was also explored. After 6 days of immobilization, approximately 25% of TN in the source water could be removed by the carriers, and the effects could last for at least 9 cycles of reuse. These results provide a good reference for the use of aerobic denitrifiers in oligotrophic reservoirs.

Simultaneous removal of carbon and nitrogen in an anaerobic inverse fluidized bed reactor

2006 ◽  
Vol 54 (2) ◽  
pp. 111-117 ◽  
Author(s):  
A. Alvarado-Lassman ◽  
E. Rustrián ◽  
M.A. García-Alvarado ◽  
E. Houbron
Keyword(s):  
Anaerobic Digestion ◽  
Carbon Source ◽  
Gas Phase ◽  
Fluidized Bed ◽  
Fluidized Bed Reactor ◽  
Synthetic Wastewater ◽  
Simultaneous Removal ◽  
Batch Experiments ◽  
Carbon And Nitrogen ◽  
Inverse Fluidized Bed

The evaluation of simultaneous removal of carbon and nitrogen in an anaerobic inverse fluidized bed reactor is described. Continuous and batch experiments were used, with synthetic wastewater and glucose as the carbon source with two different nitrate concentrations of 100 and 250 mg N-NO3/L. The evolution of substrates and the concentrations of intermediary products in the gas phase were followed. Results indicate that the use of the biofilm in the inverse fluidized bed reactor allows the expression of denitrification and methanization activities simultaneously without physical or time separation. The removal of nitrogen with both the feeding of 100 and 250 mgN-NO3/L was higher than 90%, while the removal of carbon was 65% on average for the feeding with 100 mgN-NO3/L and 70% on average for the feeding with 250 mg N-NO3/L. This carbon degradation is equivalent to that obtained during the operation of the reactor in the period previous to the nitrate feeding. It was found that by using high values of the COD/N ratio, the dissimilative reduction of nitrates is favoured. Denitrification and anaerobic digestion occurs simultaneously under low values of COD/N.

The Interactions of Carbon and Nitrogen in Liquid Silicon

2014 ◽  
Vol 33 (4) ◽  
pp. 363-368 ◽  
Author(s):  
Halvor Dalaker ◽  
Merete Tangstad
Keyword(s):  
Silicon Nitride ◽  
Carbon Source ◽  
Nitrogen Content ◽  
High Purity ◽  
Liquid Silicon ◽  
Interaction Parameters ◽  
Carbon And Nitrogen ◽  
Temperature Range ◽  
High Purity Silicon

AbstractThe interactions between carbon and nitrogen in liquid silicon have been studied experimentally. High purity silicon was melted in silicon nitride crucibles under an Ar atmosphere with a graphite slab inserted in the crucible prior to melting as a carbon source. The system was thus simultaneously equilibrated with Si3N4 and SiC. Samples were extracted in the temperature range 1695–1798 K and analyzed using Leco.It was observed that the simultaneous saturation of nitrogen and carbon caused a significant increase in the solubilities of both elements. The interaction parameters were derived as The solubility of carbon in liquid silicon as a function of temperature and nitrogen content was found to follow: And the solubility of nitrogen in liquid silicon found to follow:

scholarly journals Production of Feruloyl Esterase from Aspergillus niger by Solid-State Fermentation on Different Carbon Sources

2011 ◽  
Vol 2011 ◽  
pp. 1-4 ◽  
Author(s):  
Shiyi Ou ◽  
Jing Zhang ◽  
Yong Wang ◽  
Ning Zhang
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Wheat Bran ◽  
Cell Walls ◽  
Carbon Sources ◽  
Feruloyl Esterase ◽  
Plant Cell Walls ◽  
Optimal Conditions ◽  
Carbon And Nitrogen ◽  
Maize Bran

A mixture of wheat bran with maize bran as a carbon source and addition of (NH4)SO4 as nitrogen source was found to significantly increase production of feruloyl esterase (FAE) enzyme compared with wheat bran as a sole carbon and nitrogen source. The optimal conditions in conical flasks were carbon source (30 g) to water 1 : 1, maize bran to wheat bran 1 : 2, (NH4)SO4 1.2 g and MgSO4 70 mg. Under these conditions, FAE activity was 7.68 mU/g. The FAE activity on the mixed carbon sources showed, high activity against the plant cell walls contained in the cultures.

scholarly journals Modelling simultaneous removal of trichlorfon and glucose in a hybrid bioreactor containing magnetically immobilized biomass

1998 ◽  
Vol 38 (4-5) ◽  
pp. 179-186 ◽  
Author(s):  
Guang Hao Chen ◽  
Hiroaki Ozaki ◽  
Yutaka Terashima
Keyword(s):  
Mathematical Model ◽  
Carbon Source ◽  
Experimental Results ◽  
Simultaneous Removal ◽  
Industrial Wastewaters ◽  
Suspended Biomass ◽  
Immobilized Biomass

This paper focuses on a simultaneous removal of trichlorfon and glucose that was added as carbon source for degradation requirement of trichlorfon. A hybrid bioreactor, having both suspended and magnetically immobilized biomass, was used for investigating this removal of both substances. To evaluate the respective roles of these two types of biomass, a mathematical model was developed and also verified well with experimental results. It has been found that the suspended biomass plays a key role in removing both substances in the system. This is due to complete coexistence of both trichlorfon-degrading and glucose-removing bacteria completely in each type of the biomass. Such a system would be applicable to the treatment of complex industrial wastewaters that contain easily biodegradable organics as well as refractory pollutants.

scholarly journals Influence of cultivation conditions on IAA - producing activity of endophytic bacterial strains isolated from morning-glory (IPOMOEA PES-CAPRAE (L.) R.Br.)

2021 ◽  
Vol 36 ◽  
pp. 05003
Author(s):  
Nguyen Van Zhang ◽  
Nguyen Thi Thu ◽  
Vu Thi Linh ◽  
V.V. Pylnev ◽  
M.I. Popchenko
Keyword(s):  
Carbon Source ◽  
Culture Medium ◽  
Nitrogen Sources ◽  
Morning Glory ◽  
Bacterial Strains ◽  
Cultivation Conditions ◽  
Bacillus Mycoides ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen ◽  
Study Results

This work presents the experimental study results of the influence of the culture medium on the ability to IAA synthesis of three endophytic strains TH10R, TH11T, and TH13T from roots of Ipomoea pes-caprae. Three investigated strains give the highest IAA concentration after 96 h of cultivation. A significant increase in IAA biosynthesis was obtained by cultivating the TH10R strain in a medium containing lactose or starch as a carbon source and NH4Cl or KNO3 as a nitrogen source. The TH11T strain produces the maximum amount of IAA, using glucose or xylose and KNO3 or NH4NO3 as carbon and nitrogen sources, respectively. Sucrose is a suitable carbon source for the TH13T strain; on a sucrose-containing medium, the TH13T strain produces the highest IAA amount. The most active strain is TH10R, identified as Bacillus mycoides and named Bacillus mycoides TH10R.

scholarly journals Lovastatin Biosynthesis by Aspergillus terreus in a Chemically Defined Medium

2001 ◽  
Vol 67 (6) ◽  
pp. 2596-2602 ◽  
Author(s):  
Hassan Hajjaj ◽  
Peter Niederberger ◽  
Philippe Duboc
Keyword(s):  
Carbon Source ◽  
Aspergillus Terreus ◽  
Glucose Repression ◽  
Nitrogen Sources ◽  
Glucose Consumption ◽  
Defined Medium ◽  
Specific Productivity ◽  
Chemically Defined Medium ◽  
Carbon And Nitrogen Sources ◽  
Carbon And Nitrogen

ABSTRACT Lovastatin is a secondary metabolite produced by Aspergillus terreus. A chemically defined medium was developed in order to investigate the influence of carbon and nitrogen sources on lovastatin biosynthesis. Among several organic and inorganic defined nitrogen sources metabolized by A. terreus, glutamate and histidine gave the highest lovastatin biosynthesis level. For cultures on glucose and glutamate, lovastatin synthesis initiated when glucose consumption levelled off. When A. terreus was grown on lactose, lovastatin production initiated in the presence of residual lactose. Experimental results showed that carbon source starvation is required in addition to relief of glucose repression, while glutamate did not repress biosynthesis. A threefold-higher specific productivity was found with the defined medium on glucose and glutamate, compared to growth on complex medium with glucose, peptonized milk, and yeast extract.

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