论文部分内容阅读
目的采用酶热生物传感器法对我国部分地区巴氏杀菌乳样品中β-内酰胺酶进行快速检测及本底含量调查。方法在巴氏杀菌乳样品中预先加入一定量青霉素G,室温震荡反应3 h,使样品中的β-内酰胺酶充分酶解青霉素G底物,直接通过酶热生物传感器测定青霉素G含量。根据反应前后样品中青霉素G含量的变化,间接计算巴氏杀菌乳样品中β-内酰胺酶的活性。2013年6~8月在13个省市采集巴氏杀菌乳样品106份,对其β-内酰胺酶含量进行本底调查。结果该方法线性范围为4~20 U/ml,检出限和定量限分别为2和4 U/ml。全国106份样品的总检出率为3.8%,其中北京市的47份样品中β-内酰胺酶活性均﹤2 U/ml;其他12个省市的59份样品中β-内酰胺酶活性均﹤4 U/ml,其中4个样品在2~4 U/ml之间。结论我国13个省市106份巴氏杀菌乳样品的测定结果表明样品中β-内酰胺酶含量普遍较低,一定程度上表明我国巴氏杀菌乳中违法添加β-内酰胺酶的问题已得到较大改善。
Objective To detect the content of β-lactamases in pasteurized milk samples in some areas of China by enzymatic thermal biosensor method. Methods A certain amount of penicillin G was added into the pasteurized milk sample and reacted for 3 h at room temperature. The β-lactamase in the sample was used to fully hydrolyze penicillin G substrate, and the penicillin G content was determined directly by enzyme thermosensor. Based on the change of penicillin G content in samples before and after the reaction, the β-lactamase activity in the pasteurized milk samples was indirectly calculated. From June to August 2013, 106 samples of pasteurized milk were collected from 13 provinces and cities, and the background of β-lactamase content was investigated. Results The linear range of this method was 4 ~ 20 U / ml. The limits of detection and quantification were 2 and 4 U / ml, respectively. The total detection rate of 106 samples in China was 3.8%, among which the β-lactamase activity in 47 samples of Beijing was <2 U / ml; the β-lactamase activity in 59 samples of other 12 provinces All <4 U / ml, of which 4 samples were between 2 ~ 4 U / ml. Conclusion The results of the determination of 106 pasteurized milk samples in 13 provinces and cities in China indicate that the content of β-lactamase in the sample is generally low, to some extent, the problem of illegally adding β-lactamase in our pasteurized milk has been obtained Great improvement.