食品科学 ›› 2011, Vol. 32 ›› Issue (4): 216-219.doi: 10.7506/spkx1002-6630-201104048

• 分析检测 • 上一篇    下一篇

杯碟法检测乳中的β-内酰胺酶

薛晓晶,李 玲,金 涌,李 礼,王 芳,任香夫,田世民   

  1. 中国检验检疫科学研究院
  • 出版日期:2011-03-12 发布日期:2017-04-06

Detection ofβ-Lactamase in Milk Based on Cylinder Plate Method

XUE Xiao-jing,LI Ling,JIN Yong,LI Li,WANG Fang,REN Xiang-fu,TIAN Shi-min   

  1. Chinese Academy of Inspection and Quarantine, Beijing 100123, China
  • Online:2011-03-12 Published:2017-04-06

摘要: 采用微生物杯碟法对乳中β-内酰胺酶进行检测。基于青霉素抑制藤黄微球菌(Micrococcus luteus)生长并产生抑菌圈,利用舒巴坦特异性抑制β-内酰胺酶活性的特点,通过比较含青霉素样品中加入和未加入舒巴坦所产生的抑菌圈直径差异,间接判断样品中是否含有β-内酰胺酶。结果表明:青霉素G的最佳使用质量浓度为0.5μg/mL,β-内酰胺酶的检测限因生产厂家随标注单位不同而不一致,舒巴坦的最佳使用质量浓度为50μg/mL;在此基础上确立杯碟法检测β-内酰胺酶的优化方案:设立阴阳性样品对照组;并对同一样品进行4个不同添加处理:青霉素G处理,青霉素G、舒巴坦处理,青霉素G、β-内酰胺酶处理,青霉素G、β-内酰胺酶、舒巴坦处理,通过比较4个不同处理产生的抑菌圈直径差异,并同时参照阴阳性样品对照组结果,判定样品中是否存在β-内酰胺酶。

关键词: β-内酰胺酶, 杯碟法, 青霉素G, 舒巴坦,

Abstract: Here, we adopted microbiological cylinder plate method to detectβ-lactamase in milk. Since penicillin inhibits the growth of Micrococcus luteus, producing a zone of inhibition, the difference between the diameters of inhibition zone produced by penicillin alone and together with sulbactam, which specifically inhibits the activity ofβ-lactamase, will indirectly suggest whether or not a sample contains the enzyme. The optimum working concentration of penicillin G determined in this study was 0.5μg/mL. The influence ofβ-lactamase products from different manufacturers with different given units on the antimicrobial activity of penicillin G in liquid skim milk was evaluated, and the results showed that the limits of detection of the developed method for them were different. Addition of sulbactam at 50μg/mL provided optimum detection ofβ-lactamase. Based on the above investigations, the optimum protocol for detectingβ-lactamase by cylinder plate method in milk was that the presence or not ofβ-lactamase was identified based on differences in the diameter of inhibition zone among additions of penicillin G alone or in combination with sulbactam or/andβ-lactamase to one sample together with the results from constructed positive and negative controls.

Key words: β-lactamaseccy, linder plate method, penicillin G, sulbactam, milk

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