摘要
从海洋沉积物中分离到2株弧菌拮抗菌(H2和H4),经生理生化特性、16S rRNA基因序列分析分别鉴定为短小芽孢杆菌(Bacillus pumilus H2)和地衣芽孢杆菌(Bacillus licheniformis H4).H2和H4菌株均对需钠弧菌的生长有显著的抑制作用;但只有H2菌株在模拟养殖动物小肠环境中生长良好.选择H2进行模拟试验(20尾凡纳滨对虾虾苗为1组).结果表明,对照组(不接种)虾苗存活32h,接种弧菌的试验组虾苗仅存活16h,同时接种H2菌株和弧菌的试验组虾苗存活48h,而仅接种H2菌株的试验组虾苗存活了72h,说明菌株H2可显著提高凡纳滨对虾的存活时间.现场试验中,100L养殖池中(50尾虾/池),分别接种0(对照),103,104CFU/mL的H2菌株并养殖14d,再用104CFU/mL需钠弧菌处理14d.接种104CFU/mL H2菌株的试验组,虾的死亡率仅为12.5%,显著低于对照组的30.8%(P<0.05).接种104CFU/mL菌株H2的试验组,虾的体长、体重都略高于对照组,但各试验组之间差异不显著(P>0.05)。
Two bacterial strains, H2 and H4, were isolated from marine sediment and identified as Bacillus pumilus H2 and Bacillus licheniformis H4, respectively, based on their physiological properties and the analysis of 16S rRNA gene sequence. Both strains showed significantly inhibitory effects against the growth of Vibrio natriegens by antimicrobial activity assay. However, only strain H2 could survive in the intestinal conditions as revealed by the simulated gastro intestinal tract （GIT） test, keeping cell number stably at 10^10 CFU/mL. B. pumilus H2 was also benefit to the survival of juvenile shrimp （Litopenaeus vannamei） as revealed by the flask bottle test （20 shrimp fries for every bottle as a group）. Probiotic effect ofB. pumilus H2 to juvenile shrimp was carried out in aquaculture tanks with 100L each with 50 shrimps. Juvenile shrimp were exposed to B. pumilus H2 at 0 （as control）, 10^3 and 10^4 CFU/mL for 14d before a challenge with Vibrio natriegens at 10^4 CFU/mL for 1 d infection. The final mortality of the shrimp group treated with 10^4 CFU/mL B. pumilus H2 was only 12.5%, much lower than the group treated with 10^3 CFU/mL B. pumilus H2 （28.3%） and the control group （30.8%, P〈0.05）; and the average weight and length of the shrimp group treated with 10^4 CFU/mL B. pumilus H2 were also a bit higher than those of the control group.
出处
《中国环境科学》
EI
CAS
CSCD
北大核心
2009年第8期867-872,共6页
China Environmental Science
基金
国家自然科学基金资助项目(30671620)
江苏省科技成果转化专项(BA2005039)
国家"863"项目(2006AA100305)
