嗜热链球菌对乳中残留抗生素检测影响因素的分析

Analysis of the Affecting Factors of Thermophilic Streptococcus on Residual Antibiotics in Milk Detection

【目的】采用嗜热链球菌抑制法,检测牛乳中抗生素残留时指示菌嗜热链球菌,研究菌活力、添加菌量、菌传代数、培养温度、培养时间等因素,对其在多种条件下的生长状况及最低灵敏度的影响进行分析比较。【方法】采用GB/T 4789.27-2008嗜热链球菌抑制法(TTC法)所用嗜热链球菌的菌种纯化、活性、稀释比例、剂量、培养温度、培养时间进行筛选,对阳性,阴性对照结果进行比较,找出最低灵敏度。【结果】新复活的嗜热链球菌其活力逐渐提高,该菌适宜培养温度为37℃,1∶1稀释菌液适宜加入量为1 mL,培养时间2 h,牛奶中抗生素残留最低检出限为0.004 IU/mL。【结论】TTC法具有简便、价廉、易于开展的优点,不需昂贵的仪器和设备,不受所检测的抗生素种类所限,各种影响细菌生长的抗生素均可检出,适用于各奶站及牛乳检测机构的抗生素残留检测。

[Objective] The project aims at using thermophilic streptococcus inhibition method to detect antibiotic residues in milk thermophilic bacterium streptococcus,and carrry out comparative analysis of the lowest sensitivity affected by the various conditions such as strain energy,fungus,bacteria pass algebra,the different temperatures of cultivation and the length of time.[Method] The GB/T 4789.27-2008 thermophilic streptococcus inhibition method （TTC method） was applied in the study.The thermophilic strains of streptococcus pneumoniae and purification,activity,dilution rate,dose,filtered cultivation temperature and time were used to compare the positive and the negative control result in order to find out the minimum sensitivity.[Result] The vitality of the newly-resurrected thermophilic streptococcus was gradually increased.The bacterium is suitable for cultivating at temperature of 37℃ and 1：1 dilution microbial suitable addition amount was 1 ml.The cultivation time was 2 hours,and the minimum antibiotic residue in milk was within the limit of 0.004 IU/ml.[Conclusion] TTC method had the advantages of simple,cheap and easy characteristics to carry out the test and it does not need expensive instruments and equipments.And it was not affected by the testing types of antibiotics.Various antibiotics affecting the growth of the bacteria could be detected by it,which was applicable to all stations and milk antibiotic residues detection testing institutions.