冷藏技术对发光细菌活性及毒性测试性能的影响  

Effect of Cold Storage Method on Activity of Luminescent Bacteria and Its Performance in Toxicity Test

作　　者：郑小燕[1,2] 蔡强 彭惠民[1,3] 彭方毅[4] 贾玉玲 刘锐 何苗[5] 

机构地区：[1]重庆医科大学基础医学院,重庆400016 [2]浙江清华长三角研究院生态环境研究所,嘉兴314006 [3]重庆医科大学基础医学实验教学中心,重庆400016 [4]重庆理工大学药学与生物工程学院,重庆400050 [5]清华大学环境科学与工程系,北京100084

出　　处：《生态毒理学报》2012年第4期439-445,共7页Asian Journal of Ecotoxicology

基　　金：国家科技支撑计划课题(2011BAF02B06);浙江省科技计划项目(2010C33020);浙江省环保科研计划项目(2010010)

摘　　要：由于发光细菌的在线毒性监测技术受到了细菌生物活性稳定性保持问题的制约,探索一种脱脂牛奶菌悬液冷藏复苏方法,以提高发光细菌活性的保持时间。比较了明亮发光杆菌新鲜菌液冷藏、冻干粉菌悬液冷藏和脱脂牛奶菌悬液冷藏对发光细菌生物活性的影响,同时,比较了不同渗透压调节液对菌悬液急性毒性测试的灵敏度和稳定性的影响。结果表明,质量分数为25%的脱脂牛奶可提高发光细菌生物活性的稳定性,菌悬液冷藏7d后复苏,相对发光率仍可达92%。2%NaCl和10%蔗糖为渗透压调节液时,冷藏至第7天的发光细菌脱脂牛奶菌悬液对重金属毒性测试的灵敏度,与新鲜菌液基本相同,但添加蔗糖降低了其对有机物的测试灵敏度。利用发光细菌脱脂牛奶冷藏菌悬液对Zn^(2+)进行连续7d的毒性测试,EC_(50)的变异系数小于15%,结果稳定性良好。Long-term maintenance of biological activity of luminescent bacteria is required for the development of its application in on-line toxicity monitoring.To enhance the stability of luminescent bacteria activity,a cold storage method of skimmed-milk bacteria suspension was explored.The survival and activity of luminescent bacteria was evaluated and compared among three methods including fresh bacteria suspension cold storage,freeze-dried bacteria suspension cold storage and skimmed milk-bacteria suspension cold storage.Moreover,the effects of different osmoregulatory factors on the sensitivity and stability of toxicity tests were investigated and compared.Results showed that 25%（w/w） skimmed milk enhanced the stability of luminescent bacteria activity.The relative luminosity of luminescent bacteria reached 92% when they were reactivated after 7 days cold storage.When applying 2%（w/w） NaCl and 10%（w/w） sucrose as the osmoregulatory factors,the toxicity test sensitivity to heavy metals using skimmed milk-bacteria suspension after 7 d-cold storage was approximately the same with that of using fresh bacteria suspension.However,the addition of sucrose decreased the sensitivity of luminescent bacteria to organic compounds.The toxicity of Zn^（2＋） solutions with the same concentration was measured by using skimmed milk-bacteria suspension kept in cold storage for 7 consecutive days and the variation coefficient of EC_（50） values was less than 15%,indicating good stability of test results.

关 键 词：发光细菌 冷藏 生物活性 急性毒性 灵敏度 稳定性 在线监测 

分 类 号：X171.5[环境科学与工程—环境科学]