乳酸菌发酵法检测牛乳中抗生素残留

Determination of antibiotic residues in milk by lactic acid bacteria fermentation method

目的建立一种简单、准确的检测牛乳中抗生素残留的方法-乳酸菌发酵法。方法以接种量和温度为变量,优化发酵条件;以青霉素为目标抗生素,建立检测方法;以发酵4 h未凝乳的样品中抗生素最低浓度为检测限,测定本方法对20种抗生素的检测限;对比本方法和GB/T 4789.27方法检测111个商品乳样品中抗生素残留检出率,验证本方法的准确性。结果建立了乳酸菌发酵法检测乳中抗生素残留的具体方法;确定了本方法对8类20种抗生素的检测限,其中4类12种抗生素的检测限低于其在牛乳中的最大残留限量(MRL);本方法和GB/T 4789.27方法检测111个商品乳样品抗生素残留检出率分别为9.0%和11.7%。结论本方法操作简单,结果准确,适合企业及基层检测单位作为初筛方法检测牛乳中的抗生素残留。

Objective To establish a simple and accurate method for the determination of antibiotic residues in milk by lactic acid bacteria fermentation method. Methods The fermentation conditions were optimized by inoculation amount and fermentation temperature. The specific procedure for the lactic acid bacteria fermentation method was established by using penicillin as the target antibiotic and the detection limit for all 20 antibiotics were determined at the same time. A total of 111 commercial milk samples were detected by lactic acid bacteria fermentation method and GB/T 4789.27 method respectively to verify the accuracy of the established method. Results A specific procedure for the determination of antibiotic residues in milk by lactic acid bacteria fermentation method was established. The concentrations of 20 kinds of antibiotics in 8 categories in the milk which did not curd after 4 hours of fermentation were considered to be the detection limit of this method. The result showed that the detection limits of 12 kinds of antibiotics in 4 categories were lower than their maximum residue limits（MRLs） in milk. The positive rates of 111 milk samples detected by lactic acid bacteria fermentation method and GB/T 4789.27 method were 9.0% and 11.7%. Conclusion The lactic acid bacteria fermentation method is simple and accurate, and suitable for detection of antibiotic residues in milk as a primary screening method for enterprises and grass-roots testing organizations.