title: Effect of tourmaline on denitrification characteristics of hydrogenotrophic bacteria.
abstract: To improve the denitrification characteristics of anaerobic denitrifying bacteria and obviate the disadvantage of use of explosive hydrogen gas, tourmaline, a polar mineral, was added to the hydrogenotrophic denitrification system in this study. Microbial reduction of nitrate in the presence of tourmaline was evaluated to assess the promotion effect of tourmaline on nitrate biodegradation. The experiment results demonstrated that tourmaline speeded up the cultivation process of bacteria from 65 to 36 days. After domestication of the bacteria, nitrate (50 mg NO3 (-)-N L(-1)) was completely removed within 3 days in the combined tourmaline-bacteria system, and the generated nitrite was also removed within 8 days. The reduction rate in this system is higher relative to that in the bacteria system alone. Efficient removal of nitrate by tourmaline-supported anaerobic bacteria (without external hydrogen input) indicated that tourmaline might act as the sole hydrogen donor to sustain autotrophic denitrification. Besides the production of hydrogen, the promoted activity of anaerobic denitrifying bacteria might be caused by the change of water properties, e.g., the pH of aqueous solutions was altered to about 8.0 and the oxidation-reduction potential decreased by 62 % in the tourmaline system. The distinctive effects of tourmaline on bacteria were related to its electric properties.
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China. nkwangwei@126.com.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors.forename: Guangquan
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors.forename: Xueying
authors.initials: X
authors.lastname: Song
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors.forename: Xingyu
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Pollution Processes and Environmental Criteria of Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
authors.forename: Ya
authors.initials: Y
authors.lastname: Qiao
mesh_terms: D052818:Autotrophic Processes; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D001896:Boron Compounds / Q000737:chemistry; D058440:Denitrification; D004579:Electron Transport; D060587:Groundwater / Q000737:chemistry; D006859:Hydrogen / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008903:Minerals / Q000737:chemistry*; D053758:Nanoparticles; D009566:Nitrates / Q000032:analysis*; D010316:Particle Size; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001896:Boron Compounds; D008903:Minerals; D009566:Nitrates; D014874:Water Pollutants, Chemical; D006859:Hydrogen
keywords: Anaerobic; Denitrification; Hydrogenotrophic bacteria; Nitrate; Tourmaline