Detection and determination of stability of the antibiotic residues in cow’s milk

Abstract

In the present study, antibiotic residues were detected in milk samples collected from the dairy herds located in Karnataka, India, by microbiological assay. Subsequently, the detected antibiotics were identified as azithromycin and tetracycline, by high-performance liquid chromatography, further both the antibiotics detected in the cow milk samples were found to be at high concentration (9708.7 and 5460 μg kg-1, respectively). We then investigated the effects of temperature and pH on the stabilities of azithromycin and tetracycline to determine the degradation rate constant k using first-order kinetic equation. Results indicated that significant reduction in stability and antibacterial activity of azithromycin solution when subjected to 70 and 100°C for 24 h. While stability of tetracycline was significantly reduced when subjected to 70 and 100°C for 24 h. However no significant reduction in antibacterial activity of tetracycline was observed at respective temperatures when compared with that of control. In addition, the stabilities of azithromycin and tetracycline were found to be decreased in acidic pH 4–5. The results of the present study revealed the high risk of contamination of milk sample with veterinary antibiotics and also demonstrated the effect of temperature and pH on stability of antibiotics. Therefore the study suggest that the qualitative and quantitative screening of milk for the presence of antibiotics need to be strictly performed to ensure safe drinking milk for consumers.

Genotoxic impact of emerging contaminant amoxicillin residue on zebra fish (Danio rerio) embryos

“…Antibiotic residue monitoring is not used in standard quality control. Kurjogi stated that tetracycline residues at 70 C and 100 C had not been fully extracted from the milk and its products (Kurjogi et al, 2019). The MRL of amoxicillin in milk listed in Council Regulation No.…”

“…Full removal of tetracycline has not occurred at high temperatures and degradation of tetracycline often depends on various factors, such as types of food matrix and cooking, etc (Kurjogi et al, 2019).…”

“…Then the findings obtained were analyzed by comparing curves obtained from samples with those of standard one. The AMXR quantification was performed by comparing the sample peak area to that of the standard AMX having the corresponding chromatogram (Kurjogi et al, 2019).…”

Effects of melatonin on Dairy Herd Improvement (DHI) of Holstein cow with mastitis

“…How to evaluate the quality of fresh milk is a challenge for dairy industry since it is still debatable for justi cation of levels of nutrition and residues of antibiotics in milk [30]. Nevertheless, DHI index is adopted for the entire dairy industry to evaluate the milk quality [31].…”

Highly luminescent water-dispersed silicon quantum dots for fluorometric determination of oxytetracycline in milk samples

“…Most of the tetracyclines applied in cows are excreted with milk. Therefore, OTC residues may be present in milk [5]. World Health Organization (WHO) and Food and Drug Administration (FDA) established a maximum residue limit of 0.1 mg L -1 and 0.3 mg L -1 , respectively, for OTC in milk to care of human health 2 .…”