Screening of Ciprofloxacin and Gentamicin Residues in Pork Sold in Guwahati City and Its Periphery and Validation by Ultra-Fast Liquid Chromatography-UV/Vis

Abstract

Antimicrobial residues are unwanted substances with persistence capabilities in the food chain and harm the health of the consumers. The present study aims to detect the presence of ciprofloxacin and gentamicin residues in pork sold in Guwahati City and its surrounding areas and validation by Ultra-Fast Liquid Chromatography-UV/Vis. Pork samples were randomly collected from multiple districts that provide pork to the city of Guwahati. A microbial inhibition assay using the endospores of Bacillus subtilis MTCC 441 as the test organism was used to initially screen out 261 pork samples. Of these, 80 pork samples were subjected to further screening using the UFLC-UV/Vis (Model: Shimadzu Prominence LC-20AD, Detector: SPD-20A-UV/Vis; RP C18 Column: (BDS Premium, 250 mm x 4.6 mm, 5 µm) to confirm the residues in the pork samples. During the preliminary screening, no sample tested positive for antimicrobial residues with the exception of 3 (three) samples that were suspected of having the antimicrobial residues. On further screening using the UFLC-UV/Vis, it revealed that one sample (1.25%) tested positive for ciprofloxacin residue, but none of the samples tested positive for gentamicin residue. The ciprofloxacin residue was 0.039 µg/g, which is much below the MRL threshold recommended by Codex Alimentarius. Therefore, considering the detection of only 1.25% ciprofloxacin residue and the absence of gentamicin residue, it can be concluded that these antimicrobial substances are not abused in the pig husbandry practices and are comparatively safer for consumption in the areas under investigation. However, periodic screening of the pork samples are recommended and mass awareness drive should be carried out so the farmers can produce a healthy pig for human consumption.