养殖池塘14株芽孢杆菌的分离鉴定及抑菌效果

为了研究芽孢杆菌（Bacillus spp.）的抑菌效果，以40株水产病原菌作为指示菌，用平板法分析14株芽孢杆菌（来自养殖池塘水体，命名为SCS-158～SCS-171）的抑菌效果。结果发现:14株芽孢杆菌的24 h培养的全菌液对水产病原菌的抑菌率最高，达20.00%，其中，芽孢杆菌SCS-160、SCS-162、SCS-170对病原菌中的全部维氏气单胞菌（Aeromonas viridis）都有抑菌作用。14株芽孢杆菌中，有10株对白葡萄球菌（Staphylococcus albicans）18QW206有抑制效果。以白葡萄菌（S. albicans）18QW206为指示菌，与24 h培养的全菌液相比，芽孢杆菌的24 h培养的上清液及48 h培养的全菌液的抑菌效果均有所下降。其中，芽孢杆菌SCS-162上清液抑菌效果下降最明显，抑菌圈直径下降28.55%，芽孢杆菌SCS-164上清液抑菌圈直径下降幅度最小，为5.35%；48 h培养液抑菌效果中，芽孢杆菌SCS-160抑菌圈直径下降幅度最大（42.86%），芽孢杆菌SCS-163抑菌圈直径下降幅度最小（4.19%）。 说明芽孢杆菌对水产病原菌具有抑制效果。

Isolation and identification of 14 Bacillus strains in aquaculture ponds and analysis of their bacteriostatic effect on aquatic pathogens

Fourteen strains of Bacillus spp, named SCS-158 to SCS-171, were selected to determine their bacteriostatic effect against 40 strains of aquatic pathogens (bacterial indicators) by the streak plate method. The results show that the whole bacterial solutions of 14 Bacillus strains cultured for 24h had the highest bacteriostatic rate, up to 20.00%, of which those of the strains SCS-160, SCS-162 and SCS-170 had an inhibitory effect on all the strains of Aeromonas vickerii tested. Of the 14 Bacillus strains 10 strains had an inhibitory effect on the bacterial indicator Staphylococcus albicans 18QW206. The 24 h cultured supernatant and the 48 h cultured whole bacterial solution had a lower inhibitory effect on the bacterial indicator S. albicans 18QW206 as compared with the 24 h cultured whole bacterial solution. The inhibitory effect of the 24 h cultured supernatant of the strain SCS-162 decreased most obviously, with the diameter of the inhibition zone dropping by 28.55%, while the diameter of the inhibition zone of the strain SCS-164 dropped the least by 5.35%. In addition, the inhibition zone of the 48 h cultured whole bacterial solution of the strain SCS-160 decreased the most by 42.86%, while that of the strain SCS-163 dropped the least by 4.19%. These results indicate that Bacillus spp. had bacteriostatic effect on the aquatic pathogens.