食品中青黴素、鏈黴素、紅黴素、新黴素等殘留之檢驗方法探討

Study on Analytical Method for Residues of Penicillin, Streptomycin, Erythromycin and Neomycin in Foods

本研究進行肉品中青黴素（Penicillin）、鏈黴素（Streptomycin） 、紅黴素（Erythromycin）及新黴素（Neomycin） 殘留之檢驗法探討，並評估以之作為食品中抗生素殘留系統性分析之可行性。主要原理係將檢體分別由三種磷酸緩衝液（5%, pH6.0; 0.1M pH8.0 及 0.2M pH8.0）及一個系統性的溶媒抽取法（以甲醇，甲醇：鹽酸 =98:2v/v 及氯仿作為抽取溶媒）作選擇性抽取，即不同的抗生素羣在不同的抽取液中有不同之分布。將各抽取液點在TLC板上，經由數種展開液展開後，再以事先接有菌種之方型培養基與之接觸，培養後視所形成抑菌圈之Rf值作為鑑別殘留抗生素種類之依據；同時將檢液以圓筒平板法（cup-and-plate method）作生物檢定，依據抑菌之大小加以定量。四種抗生素添加於肉品後以溶媒及自緩衝液抽出，所得檢液以圓筒平板法檢測之檢出限量分別如下（依次為溶媒，緩衝液）：青黴素為0.02IU/g 0.2IU/g；鏈黴素及新黴素為0.5μg/g ，2.5μg/g； 紅黴素為0.1 μg/g, 0.5μg/g。以溶媒抽取之平均回收率由34.7%～85.4%，以緩衝液抽取者由24.7～79.8% 。生物自析法以cellulose aluminum sheet經7%氯化銨或pH 7.0, 0.5M 磷酸緩衝液展開較佳，各種抗生素可以依不同之Rf值區分閑來。其最低感度為青黴素0.005 IU，鏈黴素 50ng，紅黴素 10ng，新黴素10ng。

Food samples were extracted with different concentrations of phosphate buffers (5%, pH 6.0; 0.1M, pH 8.0; 0.2 M, pH 8.0) or solvent systems (methanol, methanol: HCI, chloroform), then applied to thin layer chromatography. Developed and dried plate was placed on top of rectangular bacterial agar culture for bioautography. Antibiotics were qualitatively identified by Rf values read by clear zones on agar culture. The extracts from said buffers / solvent systems were also applied with cup-and-plate bioassay method for quantitative analysis. Detection limit for antibiotics artificially contaminated in meat by solvent and buffer systems were as follows: penicillin, 0.02, 0.2 IU/g; streptomycin and neomycin, 0.5, 2.5μg/g; erythromycin, 0.1, 0.5μg/g, respectively. For TLC/ bioautographic method, 7% NH4Cl or 0.5 M phosphate buffer (pH 7.0) were found to be the best developing systems for these four antibiotics wherein cellulose aluminum sheets were applied. As low as 0.005 IU penicillin; 50 ng streptomycin; 10 ng erthromycin; 10 ng neomycin were detectable.