养殖水体氨氮降解菌的分离和初步鉴定

Isolation and Identification of Ammonia Nitrogen Degradation Strains from Aquaculture Water

为研究微生物降解和转化水体中的氨氮,进行了养殖水体氨氮降解菌的分离和初步鉴定试验。结果表明,以(NH4)2SO4为唯一氮源的选择性培养基,通过平板稀释分离,从养殖池塘中筛选出对氨氮具有高降解活力的菌株X1。当氨氮初始浓度为50 mg/L时,未活化的和活化的X1菌在48 h和24 h内的氨氮降解率分别为98.4%和97.7%。经形态鉴定以及生理生化试验,初步确定X1菌为巨大芽孢杆菌(Bacillus megaterium)。

Six ammonia nitrogen degradation strains were isolated and identified from aquaculture water to study their degradation and conversion of ammonia nitrogen in aquaculture water.The results showed that X1 strain with a high degradation activity of ammonia nitrogen was isolated from aquaculture water by plate dilution based on the selective medium with（NH4）2SO4 only,and the ammonia nitrogen degradation rate of the non-activated and activated X1 strain was 98.4% and 97.7% within 48h and 24h respectively when the initial concentration of ammonia nitrogen was 50mg/L.X1 strain was identified as Bacillus megaterium by morphological identification and physiological and biochemical tests.