食品中四環素類抗生素殘留之檢驗方法探討

MICROBIOLOGICAL METHOD OF TEST FOR TETRACYCLINES RISIDUES IN FOODS

本報告以圓筒平板法及TLC─生物自析法進行豬肉、豬肝、雞肉、雞肝、鮮乳及鮮蛋中四環素類抗生素殘留之檢驗方法探討。檢體經均質後以0.1% 檸檬酸：乙醇（7：3） 混合液萃取，再經XAD-2吸附性樹脂管柱淨化，最後以甲醇溶離，所得檢液分別利用圓筒平板法及生物自析法定性定量。圓筒平板法之最低檢出限量羫四環素（OTC），四環素（TC）均為0.05μ/g，氯四環素（CTC）則為0.01μg/g。鮮肉及內臟中OTC回收率89.7%～92.7%，TC81.3%～84.7%，CTC83.3%～88.0%；鮮乳之CTC平均回收率為86.3%，鮮蛋之CTC平均回收率為73.3%。在生物自析法中以正丁醇：醋酸：去離子水（10：1：2）展開液展開後，Rf值分別為CTC0.52，CTC0.32及TC0.43，感度三種均達5ng。於檢體中分別添加鏈黴素、林可黴素、健牠黴素、新黴素5μg/g，結果均無抑制圈形成；泰黴素、紅黴素在5μg/g時有抑制圈，2.5μg/g時則無抑制圈形成；配尼西林在0.03，0.02μg/g時有抑制圈，0.01μg/g時則無抑制圈形成。由市面抽購120件檢體進行實驗，結果僅檢出豬肝1件中有OTC0.062ppm之殘留，符合規定。

The cup-plate-method and TLC-bioautographic method were tested for analyzing the residual tetracyclines (TCs) in pork, pork liver, chicken muscle, chicken liver,egg and milk. After extraction with 0.1% citric acid: ethane} solvent (7 : 3) from homogenized samples the extract was concentrated. The concentrated solution was passed throμgh AmbeiteAD-2 resin column and then eluted with methanol. The eluate was devided into two parts for quantity and qualitative analysis using the cup- plate- method and TLC- bioautography. The recoveries of OTC added to meats and livers were 89.7% and 92.7%, respectively; those of TC were 81.3% and 84.7%; those CTC were 83.3% and '88.0%. The average recovenes of CTC add to milk was 88.3%, while CTC in egg was 73.3%. As little as 0.05μg/g (OTC, TC) or 0.01 μg/g (CTC) was detectable in cup-plate-method. TLC plate was developed by the solvent system of butanol: acetic acid: deionized water (10 : 1 : 2), their Rf valueswere CTC 0.52, OTC 0.32 and TC 0.43, respectively. All of the sensitivity was 5ng. Other antibiotics were also added to sample and detected by the cup-plate-method. Results of milk and Streptomycin (5μg /g), Lincomycin (5μg/g), Gentamycin (5μg/g), Neomycin (5μg/g), Tylosin (2.5μg/g), Erythromycine (0.5μg/g) or Penicillin (0.01μ/g) showed no inhibition zone; but in Tylosin (5μg/g), Erythromycin (5μg/g) and penicillin (0.03μ/g, 0.02μ/g) inhibition zones occured.