Combination of heterotrophic nitrifying bacterium and duckweed (Lemna gibba L.) enhances ammonium nitrogen removal efficiency in aquaculture water via mutual growth promotion.
We created a combined system using duckweed and bacteria to enhance the efficiency of ammonium nitrogen (NH4+-N) and total nitrogen (TN) removal from aquaculture wastewater. Heterotrophic nitrifying bacterium was isolated from a sediment sample at an intensive land-based aquaculture farm. It was identified as Acinetobacter sp. strain A6 based on 16S rRNA gene sequence (accession number MF767879). The NH4+-N removal efficiency of the strain and duckweed in culture media and sampled aquaculture wastewater at 15°C was over 99% without any accumulation of nitrite or nitrate. This was significantly higher than strain A6 or duckweed alone. Interestingly, the presence of NO3- increased NH4+-N removal rate by 35.17%. Strain A6 and duckweed had mutual growth promoting-effects despite the presence of heavy metals and antibiotics stresses. In addition, strain A6 colonized abundantly and possibly formed biofilms in the inner leaves of duckweed, and possessed indoleacetic acid (IAA)- and siderophore-producing characteristics. The mutual growth promotion between strain A6 and duckweed may be the reason for their synergistic action of N removal.
['Shen|Min|M|', 'Yin|Zhifeng|Z|', 'Xia|Dan|D|', 'Zhao|Qingxin|Q|', 'Kang|Yijun|Y|']
D000150:Acinetobacter D035961:Alismatales D064751:Ammonium Compounds D017756:Aquaculture D001673:Biodegradation, Environmental D052836:Heterotrophic Processes D000076662:Host Microbial Interactions D010802:Phylogeny D012722:Sewage D013696:Temperature D014865:Waste Disposal, Fluid D014874:Water Pollutants, Chemical D018508:Water Purification
duckweed ammonium nitrogen removal aquaculture wastewater Acinetobacter sp.