假丝酵母菌降解养殖水体氨氮的特性研究

Characteristics of degrading NH_3-N in the fishery water by Candida sp.

为筛选降解养殖水体氨氮的功能菌,从海水中取样,用212mg/L氨氮浓度的分离培养基进行培养,筛选获得了一株能高效降解养殖水体氨氮功能的菌株,经鉴定为假丝酵母菌。通过研究养殖水体氨氮浓度、pH值、温度等因素对菌株降解氨氮作用的影响,结果表明,菌株降解氨氮较适宜的条件为养殖水体氨氮≤20mg/L,pH值6～7,温度25～30℃,盐浓度0～1%,溶氧2mg/L以上。假丝酵母菌在这种水体生态条件下接种5%,氨氮降解率接近80%。

A strain which can effectively degrade NH3-N in the fishery water was obtained from sea water by culturing in the isolating medium in which the concentration of NH3-N was 212 mg/L. It was identified as Candida sp. The factors affecting the degradation of NH3-N by Candida sp. such as the concentration of NH3-N, pH value, temperature were studied. The results showed that the suitable conditions were as follows ： the concen- tration of NH3-N≤20 mg/L, pH value 6-7, temperature 25-30℃, the salinity 0-1% and the dissolved oxygen concentration 〉2 mg/L. under this condition, the degradation rate of NH3-N can reach 80% when the inoculum of Candida sp. was 5%.