Characterizing the microbially mediated feammox process: temperature effect and electron acceptors
- Authors
- Ruiz Urig?en, Melany
- Format
- MasterThesis
- Status
- publishedVersion
- Description
Feammox is the name given to the bacterial-mediated form of anaerobic ammonium oxidation under iron reducing condition. Feammox is a novel pathway in the nitrogen cycle, and a key process for alleviating ammonium accumulation in anoxic soils. Biogeochemical processes that regulate the removal of compounds in the environment are affected by numerous factors such as temperature, and no such study has been previous conducted with enriched cultures of Acidimicrobiaceae-bacterium A6, the recently discovered bacteria group found to be responsible of Feammox (Huang and Jaffe, 2013). The research presented herein examines the effect of temperature on the bacterial-mediated Feammox process in batch experiments under controlled pH and nutrient concentration conditions, in order to determine its temperature dependent kinetics. It also takes a first approach to examine the effect of anthraquinone-2,6-disulfonate (AQDS) as a possible electron shuttle to enhance electron transfer from the oxidized ammonium to the iron particle. Finally, preliminary tests were carried out to determine if Fe oxide formed from oxidizing Fe(0) could act as possible respirable iron. Results indicate that the highest ammonium removal occurs at 20?C. AQDS does not have an effect on the rate of ammonium removal; nonetheless, in its presence less iron is reduced suggesting that AQDS could act as an electron acceptor. Finally, the types of ferric iron analyzed showed to support Feammox; however, further studies are required to understand the extent of their bioavailability. The results contribute to deepen our knowledge of the biogeochemical needs of the bacterial mediated Feammox process under cultured conditions in order to optimize it. Moreover, the temperature effect also allows us to establish the feasibility of the Feammox-bacteria application for wastewater treatment without the costly oxygen input and at temperatures less favorable for other anaerobic ammonium removal mechanisms.
- Publication Year
- 2014
- Language
- eng
- Topic
- BIOGEOQU?MICA
AMMONIUM OXIDATION
IRON REDUCTION
ACTINOBACTERIA
- Repository
- Repositorio SENESCYT
- Rights
- openAccess
- License