scholarly journals Performance and Mechanism of UV/Immobilized Cu-TiO2System to Degradation Histidine

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Cheng Liu ◽  
Jie Wang ◽  
Wei Chen ◽  
Zhehao Sun ◽  
Zhen Cao
Keyword(s):  
Amino Acids ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Degradation Rate ◽  
Ph Value ◽  
Disinfection Byproducts ◽  
Photocatalytic Efficiency ◽  
Inorganic Ion ◽  
Performance And Mechanism ◽  
Optimal Ph

More and more attention is paid to dissolved organic nitrogen (DON) and some specific categories of amino acids are considered to be the direct precursors of nitrogenous disinfection byproducts (N-DBPs). Histidine was chosen to study the efficiency and mechanism of amino acid in UV/Cu-TiO2system. Moreover, the influences of pH, organics, and inorganic ion on the photocatalytic efficiency were also investigated. The results show that the degradation rate of DON in the UV/Cu-TiO2system was about 50% after 60 min, and it was much lower than that of histidine (72%), which indicated that a part of degraded histidine was oxidized to other N-containing organics. The optimal pH value was 7.0 for the photodegradation of histidine, and the presence of organic compound and inorganic ion would decrease the degradation performance to some extent. After 6 h irradiation, histidine was totally degraded intoNH4+, and in the following 2 h,NH4+was oxidized toNO3-firstly and thenNO3-was reduced to N2and overflowed from water, which should be attributed to the doping of Cu in the TiO2and provided a way to totally degrade the DON from the water.

scholarly journals Sorptive fractionation of dissolved organic nitrogen and amino acids onto fine sediments within the Amazon Basin

2001 ◽  
Vol 46 (8) ◽  
pp. 1921-1935 ◽  
Author(s):  
Anthony K. Aufdenkampe ◽  
John I. Hedges ◽  
Jeffery E. Richey ◽  
Alex V. Krusche ◽  
Carlos A. Llerena
Keyword(s):  
Amino Acids ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Amazon Basin ◽  
Fine Sediments

Biodegradation of Swainsonine by Stenotrophomonas maltophilia Strain YLZZ-2 and its Isolation and Identification

2010 ◽  
Vol 178 ◽  
pp. 59-64
Author(s):  
Xing Hua Zhao ◽  
Xin He ◽  
Jian Hua Wang
Keyword(s):  
Stenotrophomonas Maltophilia ◽  
Sole Carbon Source ◽  
Degradation Rate ◽  
Ph Value ◽  
Culture Conditions ◽  
Isolation And Identification ◽  
16S Rdna Sequence ◽  
Degrading Bacteria ◽  
Initial Ph ◽  
Optimal Ph

Eight swainsonine (SW)-degrading bacteria were isolated from the soil where locoweed was buried for 6 months and one of the strains (YLZZ-2) was selected for further study. Based on morphology, physiologic tests, 16S rDNA sequence, and phylogenetic characteristics, the strain showed the greatest similarity to members of the order Stenotrophomonap and the closest to members of the Stenotrophomonas maltophilia group. The ability of the strain to degrade SW, as sole carbon source, was investigated under different culture conditions. The preferential temperature and initial pH value for the strain were 25～35 °C and 6.0～9.0, respectively. The optimal temperature for the strain was 30 °C and the optimal pH value was 7.0. There was positive correlation between degradation rate and inoculation amount. The growth of stain YLZZ-2 and degradation rate were fast, and YLZZ-2 could completely degradate 400 mg/L swainsoine within 24 h. There was a linear relationship between the growth of stain YLZZ-2 and degradation of swainsonine. These results highlight the potential of this bacterium to be used in detoxifying of SW in livestock consuming locoweed.

Characterization of DON in IOM derived from M. aeruginosa and its removal by sunlight/immobilized TiO2system

RSC Advances ◽  
2015 ◽  
Vol 5 (51) ◽  
pp. 41203-41209 ◽  
Author(s):  
Cheng Liu ◽  
Jie Wang ◽  
Wei Chen ◽  
Haoqiang Zhu ◽  
Hongkai Bi
Keyword(s):  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Water Sources ◽  
Disinfection Byproducts ◽  
Eutrophic Water

Dissolved organic nitrogen (DON) is now considered as one of the most important precursors of nitrogenous disinfection byproducts (N-DBPs), and the algae cells were the main source of DON in eutrophic water sources.

scholarly journals Limited accessibility of nitrogen supplied as amino acids, amides, and amines as energy sources for marine Thaumarchaeota

2021 ◽  
Author(s):  
Julian Damashek ◽  
Barbara Bayer ◽  
Gerhard J Herndl ◽  
Natalie J Wallsgrove ◽  
Tamara Allen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Heterotrophic Bacterium ◽  
Field Studies ◽  
Primary Amines ◽  
Energy Sources ◽  
Sterile Seawater ◽  
Axenic Cultures ◽  
Sole Energy

Genomic and physiological evidence from some strains of ammonia-oxidizing Thaumarchaeota demonstrate their additional ability to oxidize nitrogen (N) supplied as urea or cyanate, fueling conjecture about their ability to conserve energy by directly oxidizing reduced N from other dissolved organic nitrogen (DON) compounds. Similarly, field studies have shown rapid oxidation of polyamine-N in the ocean, but it is unclear whether Thaumarchaeota oxidize polyamine-N directly or whether heterotrophic DON remineralization is required. We tested growth of two marine Nitrosopumilus isolates on DON compounds including polyamines, amino acids, primary amines, and amides as their sole energy source. Though axenic cultures only consumed N supplied as ammonium or urea, there was rapid but inconsistent oxidation of N from the polyamine putrescine when cultures included a heterotrophic bacterium. Surprisingly, axenic cultures oxidized 15N-putrescine during growth on ammonia, suggesting co-metabolism or accelerated breakdown of putrescine by reactive metabolic byproducts. Nitric oxide, hydrogen peroxide, or peroxynitrite did not oxidize putrescine in sterile seawater. These data suggest that the N in common DON molecules is not directly accessible to marine Thaumarchaeota, with thaumarchaeal oxidation (and presumably assimilation) of DON-N requiring initial heterotrophic remineralization. However, reactive byproducts or enzymatic co-metabolism may facilitate limited thaumarchaeal DON-N oxidation.

scholarly journals Characteristics of Dissolved Organic Nitrogen in Municipal and Biological Nitrogen Removal Wastewater Treatment Plants in Jordan

2019 ◽  
Vol 21 (2) ◽  
pp. 1-12
Author(s):  
Mohammed Ali Wedyan ◽  
Esam Qnais ◽  
Khalil Altaif ◽  
Abdel Al-Tawaha
Keyword(s):  
Amino Acids ◽  
Free Amino ◽  
Dissolved Organic Nitrogen ◽  
Organic Nitrogen ◽  
Wastewater Treatment Plants ◽  
Algal Growth ◽  
Biological Nitrogen Removal ◽  
Future Improvement ◽  
Hydrophilic Compounds ◽  
Biological Nitrogen

Abstract The investigation is conducted on the biochemical form and characteristics of wastewater-derived DON in three different WWTPs in Jordan. The main eliminations of DON and biodegradable dissolved organic nitrogen (BDON) noticed along the treatment course are in the Irbid (ITP). Dissolved combined amino acids (DCAA) and dissolved free amino acids (DFAA) in the outlet accounted for less than 4% of the outlet DON of all plants. The DON from the outlet was composed of 90% hydrophilic compounds which stimulate algal growth. The study provided information for future improvement of WWTPs of Jordan and for adjusting the assortment of DON elimination systems to comply with stricter limits.

Sign in / Sign up

Export Citation Format

Share Document