Detection and Evaluation of penicillin base antibiotics residue in the kidney, liver and meat of the cow distributed in Tehran’s municipal markets by using ELISA kits followed by high performance liquid chromatography

Antibiotic residues in meat and other foods of animal origin have adverse effects on consumer health. In this study, first, penicillin residues of 45 samples (15 meat samples, 15 liver samples and 15 kidney samples) randomly collected from Tehran retailers were evaluated by ELISA method. Based on ELISA results, from total 45 samples, 43 cases were diagnosed as contaminated sample for antibiotic residues. The highest penicillin amount was observed for liver samples but there was no significant difference between kidney and liver samples (p=0.895). Subsequently, samples with equal amounts of penicillin were removed and other samples were analyzed by high performance liquid chromatography (HPLC) regarding penicillin G, ampicillin and amoxicillin. Penicillin G had the most value among other penicillin groups followed by ampicillin and amoxicillin, respectively. Liver samples showed higher levels of penicillin groups compared to meat and kidney samples, but no significant difference was found among them. Also, there was good correlation between ELISA and HPLC results and R2 of all samples was greater than 0.99. Moreover, it was demonstrated that antibiotic residues of some samples were above the maximum residue limit (MRL) stated by world standards. Obtained results show the necessity of monitoring antibiotic residues in food of animal origin by related organizations especially the institute of standards & industrial research of Iran and veterinary organization.