一株降解刺参残饵的芽孢杆菌分离、鉴定及施用效果

Isolation,Identification and Application of Bacillus Degrading Residual Feed of Sea Cucumber

从刺参养殖底泥、肠道、水体中共分离纯化得到36株菌落形态不同的芽孢杆菌,研究36株菌对刺参残饵的降解效果,从中筛选了一株降解效果较好的芽孢杆菌,将其命名为B12,经形态特征、生理生化特性和16SrDNA序列相似性分析,鉴定其为巨大芽孢杆菌,菌株接种浓度为105 cfu/mL时,在18℃培养2d后,对刺参饵料培养基中的COD的降解率为43.12%,氨氮的降解率为73.13%,将菌株B12于发酵罐发酵,得到菌液在养殖池塘施用,48h后氨氮降至0.0377mg/L,净化水质效果较好。

A total of 36 strains of Bacillus with different colony morphology were isolated and purified from the culturing sediment and water and the gut of Apostichopus japonicus.The degradation on the residual feed of all the strains was studied.A bacterium named B12 with the characteristic of high degradation of residual feed was selected.The morphological characteristics and physiological and bio-chemical tests of B12 were studied.Through the 16 s rDNA sequence similarity analysis,B12 was preliminarily identified as Bacillus megaterium.The lowest degradation rate of B12 to COD and NH4+-N is 43.12%and 73.13%within two days at 18℃while the concentration of the strain was 105cfu/mL.The bacterial liquid was applied in the culture pond after fermentation.The concentration of NH4+-N decreased to 0.0377 mg/L during 48 h.B12 has a good effect on purifying water.