Detection Of Antibiotic Residues Research Articles

Detection and quantification of antibiotic residues in goat milk in Mahikeng Local Municipality

Detection and quantification of antibiotic residues in goat milk in Mahikeng Local Municipality

Rapid discrimination and ratio quantification of mixed antibiotics in aqueous solution through integrative analysis of SERS spectra via CNN combined with NN-EN model

IntroductionAbusing antibiotic residues in the natural environment has become a severe public health and ecological environmental problem. The side effects of its biochemical and physiological consequences are severe. To avoid antibiotic contamination in water, implementing universal and rapid antibiotic residue detection technology is critical to maintaining antibiotic safety in aquatic environments. Surface-enhanced Raman spectroscopy (SERS) provides a powerful tool for identifying small molecular components with high sensitivity and selectivity. However, it remains a challenge to identify pure antibiotics from SERS spectra due to coexisting components in the mixture. ObjectivesIn this study, an intelligent analysis model for the SERS spectrum based on a deep learning algorithm was proposed for rapid identification of the antibiotic components in the mixture and quantitative determination of the ratios of these components. MethodsWe established a water environment system containing three antibiotic residues of ciprofloxacin, doxycycline, and levofloxacin. To facilitate qualitative and quantitative analysis of the SERS spectra antibiotic mixture datasets, we developed a computational framework integrating a convolutional neural network (CNN) and a non-negative elastic network (NN-EN) method. ResultsThe experimental results demonstrate that the CNN model has a recognition accuracy of 98.68%, and the interpretation analysis of Shapley Additive exPlanations (SHAP) shows that our model can specifically focus on the characteristic peak distribution. In contrast, the NN-EN model can accurately quantify each component's ratio in the mixture. ConclusionIntegrating the SERS technique assisted by the CNN combined with the NN-EN model exhibits great potential for rapid identification and high-precision quantification of antibiotic residues in aquatic environments.

Dual-mode detection of antibiotic drugs using ytterbium molybdate/porous carbon nanocomposite

Monitoring the levels of metronidazole (MTZ) is crucial to ensure the desired therapeutic effectiveness and to prevent potential harm to patients. However, MTZ exhibits concentration-dependent antimicrobial activity and has a narrow therapeutic range. In this study, “one stone two mango” strategy was influenced for the electrochemical and UV–vis spectroscopy detection of antibiotic residues of MTZ. The successfully synthesized ytterbium molybdate nano petals (YbMO) with porous carbon (PC) nanocomposite (NC) using ultrasonication method. The YbMO/PC NC, as well as other modified electrodes, were identified and targeted as molecules using natural pH as the probe to indicate current intensity. Also, examined the morphology and physicochemical properties of the synthesized materials. Furthermore, conducted cycling voltammetry (CV) and linear sweep voltammetry (LSV) on the modified electrodes to model MTZ analytes. Among them, the YbMO/PC NC/GCE exhibited larger reduction peak current and lower potential compared to other modified electrodes due to the synergistic effect between YbMO and PC, resulting in effective detection of MTZ. The YbMO/PC NC/GCE demonstrated exceptional sensitivity (3.28 µA µM−1 cm−2), a wide linear range (0.01–10.61 and 20.61–1630.61 µM), and a remarkably low detection limit (LOD: 0.006 µM). The proposed YbMO/PC NC/GCE exhibits the successfully analyzed MTZ in serum (101%), urine (97.9%), tablets (99.15%), lake (99.1%), and river water (99.8%). On the other hand, a UV–vis spectrometric method was employed to detect MTZ. The results showed a wide linear range (0.05–57.2 µM) and an impressive LOD (70 nM). These results are attributed to the heightened sensitivity, selectivity, repeatability, and durability of the sensor.

A double defects-dominated flexible TiO2 matrix for in-situ SERS sensing of antibiotic residues in aquatic ecosystem (fish & fishpond water) and their on-site degradation in flowing water

High-performance flexible semiconductor material can be used as an excellent multifunctional matrix for in-situ ultrasensitive surface-enhanced Raman scattering (SERS) detection and synchronous photocatalytic degradation of antibiotic residues in aquatic ecosystem. Here, a calcium-doped TiO2 flexible matrix with double defects (surface oxygen vacancy defect and Ti3+ energy level defect) was developed by its “in-situ one-step” hydrothermal synthesis on cotton fabric for the above purposes. Due to the joint contribution of double defects, a multi-channel charge transfer mode and a high-efficiency carrier separation are achieved, which endows flexible cotton fabric/Ca-doped TiO2 (Cot/Ca-TiO2) substrate with the greatly boosted SERS effect for in-situ detection of antibiotic residues on fish body surface and in fishpond water by a simple wiping or dipping sampling method, even for simultaneous identification of multi-component residues. The detection limits of three antibiotic residues (enrofloxacin, ciprofloxacin and enoxacin) are as low as 10−9 M, which are far lower than the EU standard. More meaningfully, the flexible Cot/Ca-TiO2 can be used as a multifunctional filter-membrane type photocatalyst for efficient on-site degradation of antibiotic residues in flowing fishpond water by a multi-grade photocatalysis means. Moreover, the flexible matrix exhibits good recyclability in both actual detection and photocatalysis.

Detection of antibiotic residues in groundwater with a validated multiresidue UHPLC-MS/MS quantification method

The occurrence of antibiotic residues in the environment has received considerable attention because of their potential to select for bacterial resistance. The overuse of antibiotics in human medicine and animal production results in antibiotic residues entering the aquatic environment, but concentrations are currently not well determined. This study investigates the occurrence of antibiotics in groundwater in areas strongly related to agriculture and the antibiotic treatment of animals. A multiresidue method was validated according to EU Regulation 2021/808, to allow (semi-)quantitative analysis of 78 antibiotics from 10 different classes: β-lactams, sulfonamides, tetracyclines, lincosamides, amphenicols, (fluoro)quinolones, macrolides, pleuromutilins, ansamycins and diaminopyrimidines using ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). This method was used to test different storage conditions of these water samples during a stability study over a period of 2 weeks. Sulfonamides, lincosamides and pleuromutilins were the most stable. Degradation was most pronounced for β-lactam antibiotics, macrolides and ansamycins. To maintain stability, storage of samples at −18 °C is preferred. With the validated method, antibiotic residues were detected in groundwater, sampled from regions associated with intensive livestock farming in Flanders (Belgium). Out of 50 samples, 14% contained at least one residue. Concentrations were low, ranging from < LOD to 0.03 μg/L. Chloramphenicol, oxolinic acid, tetracycline and sulfonamides (sulfadiazine, sulfadoxine, sulfamethazine and sulfisoxazole) were detected. This study presents a new method for the quantification of antibiotic residues, which was applied to investigate the presence of antibiotic residues in groundwater in Flanders.

Synergetic Effect of β-Cyclodextrin and CuO Nanocomposite for Ultrasensitive Determination of Chloramphenicol in Food

Chloramphenicol (CAP), a broad-spectrum antibiotic, has severely impacted human health and the ecological environment, which brings an increasing demand for an efficient monitoring technology for rapid and sensitive antibiotic residue detection. Herein, a highly sensitive and selective electrochemical sensor was developed for detecting CAP, based on the synergistic effect of β-cyclodextrin (β-CD) and CuO-nanomaterials modifying glassy carbon electrode (GCE). Scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD) spectrometry were used for morphological characterization. β-CD/CuO/GCE sensor with high-specific surface area and cavity structure was prepared by modifying GCE for further electrochemical testing. Experimental parameters were optimized using square wave stripping voltammetry. The developed sensor obtains an ultra-wide linear range from 1.0 × 10−7 mol l−1 to 5.0 × 10−4 mol l−1and the limit of detection is 0.5 × 10−7 mol l−1. The sensor displays high sensitivity, remarkable stability, and reproducibility; particularly more convenient than the Liquid chromatography-mass spectrometry (LC-MS) verification method. Furthermore, the applicability of the developed β-CD/CuO/GCE sensor was demonstrated by detecting CAP in food samples.

A flexible semiconductor SERS substrate by in situ growth of tightly aligned TiO2 for in situ detection of antibiotic residues.

Semiconductor materials have become a competitive candidate for surface-enhanced Raman scattering (SERS) substrate. However, powdered semiconductors are difficult to execute a fast in situ detection for trace analytes. Here, we developed a new flexible semiconductor SERS substrate by in situ densely growing anatase TiO2 nanoparticles on the surface of cotton fabric through a filtration-hydrothermal method, in which TiO2 exhibits excellent controllability in size and distribution by regulating the ratio of water to alcohol in synthesis and the number of filtration-hydrothermal repetitive cycle. Cotton fabric/TiO2 (Cot/TiO2) substrate exhibits a high SERS activity and excellent spectral repeatability. The developed substrate has an ultra-high stability that can withstand long-term preservation; it can even resist the corrosions of strong acid and alkali, as well as high temperature up to 100°C and low temperature down to - 20°C. The flexible substrate can be used to carry out a rapid in situ detection for quinolone antibiotic (enrofloxacin and enoxacin) residues on the fish body surface by using a simple swabbing method, with highquantitative detection potential (up to an order of magnitude of 10-7M), and even for the simultaneous detection of both drug residues. The flexible substrate also exhibits an excellent recyclability up to 6 recycles in the actual SERS detection.

Retracted: A Review of Detection of Antibiotic Residues in Food by Surface-Enhanced Raman Spectroscopy.

[This retracts the article DOI: 10.1155/2021/8180154.].

A colorimetric and phosphorescent dual-mode nanosensing platform for the sensitive detection of tobramycin in dairy products

Potential tobramycin (TOB) residues in dairy products have become a concern for food safety, and their accumulation in the food chain may cause great harm to human health. Therefore, in this study, a colorimetric and phosphorescent dual-mode aptamer-sensing platform was developed. The gold nanoparticle (AuNP)-based colorimetric assay is convenient and cost-effective and can be used for semi-quantitative detection by observation with the naked eye. Zn2GeO4:Mn2+ persistent luminescent nanoparticles (PLNPs) without autofluorescence luminescence characteristics and the inner filter effect with AuNPs were introduced to realize more sensitive detection of TOB. Compared to the colorimetric mode with a detection limit of 1.04 μg L−1, the phosphorescent mode with detection limit of 2.48 × 10−3 μg L−1 has higher selectivity and sensitivity for TOB in food samples. Thus, phosphorescent detection is more than three orders of magnitude more computationally sensitive than colorimetric assays. Additionally, this sensing platform was successfully applied to actual samples such as milk, yogurt, and cheese, with 94%–106% recovery rate. This study is expected to expand the application of PLNPs in food-sensing detection, providing a new strategy for the analytical detection of antibiotic residues in food.

Sense and Shoot: Multifunctional CaO2-loaded Cu-MOF nanosheets for integrated fluorescence detection and fenton-like degradation of tetracycline

Simultaneous accomplishment of sensitive detection and efficient degradation of antibiotics residues exposed in the aqueous environments has proved to be a difficult endeavor. Here, multifunctional composite CaO2-loaded Cu-MOF nanosheets (CaO2@Cu-MOF NSs) was elaborately designed and synthesized. Triggered by H+, the composite is not only capable of producing Ca2+ as the signal factor for tetracycline (TC) detection by activating the fluorescence emission of calcein, but also capable of self-supplying H2O2 and Cu2+ to construct a novel Fenton-like oxidation and O2 activation system for TC degradation based on Cu2+/Cu+ cycle. Under the synergy of target cycling and nano-enhancement, the sensing system exhibited great TC detection performance with a linear range of 0.001 to 100 ng mL−1 and detection limit of 11.8 fg mL−1. At the same time, the degradation system exhibited favorable degradation performance under the systematic action of Fenton-like and O2-activated oxidation. Nearly 80 % of the TC residues could be degraded within 10 min, and more than 95 % within 60 min. The constructed system was successfully applied to detect and degrade exposed TC in actual water samples in an integrated manner, demonstrating great promise for practical applications.

Detection of antibiotic residues in broiler chicken meat in traditional markets in Surakarta City

This research aims to detect the presence of penicillin, tetracycline, aminoglycoside, and macrolide antibiotic residues in broiler chicken meat sold in traditional markets in Surakarta City. A total of 60 research samples were collected from traditional markets. Subsequently, the samples were examined at BBVet Wates, Yogyakarta, to identify the presence of antibiotic residues. The results showed that 16.67% of the chicken breast meat samples tested positive for penicillin and 10% showed traces of macrolide antibiotic residues. For chicken thigh meat, 63.33% tested positive for penicillin, while 3.33% contained macrolide antibiotic residues. However, no tetracycline and aminoglycoside antibiotic residues were detected in any of the meat samples. The presence of antibiotic residues can be attributed to several factors, including the excessive addition of antibiotics in feed, improper use of antibiotics in livestock. Based on the research results, it can be concluded that penicillin and macrolide antibiotic residues are still prevalent in broiler chicken meat sold in traditional markets in Surakarta. This shows there is a pressing need to strengthen guidance and supervision of antibiotic use regulations, as well as to monitor antibiotic residues in the meat before it reaches the market.

Detection of Multiple Antibiotic Residues in Turkish Pine and Blossom Honeys Using LC-MS/MS Method.

Due to the high demand for honey, beekeepers often feed the bees with antibiotics to protect honeybees against illnesses; the determination of veterinary drugs and their residues in bee products especially in honey is gaining importance. In this study, commercially available 15 different brands, a total of 22 honey (14 blossoms and 8 pines) samples obtained from 5 chain supermarkets in the city of Bingöl and Diyarbakır, Turkey were analysed for 29 antibiotic residues. These antibiotics belong to 10 different categories, including tetracyclines, aminoglycosides, macrolides, sulfonamides, fluoroquinolones, benzimidazoles, anthelmintic, amphenicols, quinolines, and oxazolidines. For the qualitative and quantitative determination of the antibiotics, a triple quadrupole liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used. A total of 10 out of 22 honey (8 blossom, 57.14 % and 2 pine, 25 %) samples were found to be positive for antibiotics. Among the tested antibiotics, tetracycline, dihydrostreptomycin, streptomycin, erythromycin, and sulfadimidine were detected in the honey samples. Dihydrostreptomycin and sulfadimidine were detected in 6 samples, erythromycin was determined in 4 samples, streptomycin was found in 2 samples, and lastly, tetracycline was detected only in one sample. The highest and the lowest concentrations of antibiotics detected in the samples were dihydrostreptomycin and erythromycin found at the amount of 992.58 μg/kg and 0.77 μg/kg respectively. The proposed method was validated with a limit of quantification (LOQ) and limit of detection (LOD) ranging between 0.42 and 3.22 μg /kg and 0.13-0.97 μg /kg respectively. Good linearities were also achieved ranging between R2 =0.987 and 0.999.

Antenna effect enhanced ECL immunoassay using microfloral europium porphyrin coordination polymers based on Eu3+ and TCPP for the detection of chloramphenicol in foods.

The "antenna effect" is one of the most important energy transfer modes in lanthanide light-emitting polymers. In this study, novel luminescent nanostructured coordination polymers (Eu-PCP) were synthesized in one step using Eu3+ as the central metal ion and 5,10,15,20-tetrakis (4-carboxyphenyl) porphyrin (TCPP) as the organic ligand. The unique "antenna effect" observed between Eu3+ and TCPP leads to a substantial improvement in the electrochemiluminescence (ECL) emission efficiency. Eu-PCP exhibits good cathodic ECL characteristics. Additionally, Au@SnS2 nanosheets exhibit favorable electrical conductivity, biocompatibility, and a significant specific surface area. This makes them a suitable choice as substrate materials for the modification of electrode surfaces and capturing antigens. Being well known, the development of sensitive and rapid methods to detect chloramphenicol is essential for food safety. Based on this, we report a novel competitive electrochemiluminescence immunoassay to achieve ultra-sensitive and highly specific detection of chloramphenicol. The linear range was 0.0002-500 ng mL-1 and the detection limit was 0.09 pg mL-1. Apart from that, the experimental results proved that it provided a new analytical tool for the detection of antibiotic residues in food safety.

High energy facet-dominated TiO2−X facet heterojunction with excellent carrier utilization for ultrasensitive SERS sensing and efficient degradation of antibiotic residues

Realizing efficient utilization of photogenerated carriers is crucial to boosting the photophysical and photochemical performances of semiconductors. Herein, (101) and (001) facets co-exposed anatase TiO2−X facet heterojunction with abundant oxygen vacancies was developed as a new surface-enhanced Raman scattering (SERS) substrate and also as an excellent photocatalyst for synchronous detection and degradation of antibiotic residues in actual water system. Due to the efficient carrier separation induced by facet heterojunction and the efficient charge migration derived from exposure of more high energy (001) facets, the TiO2−X facet heterojunction exhibits an ultrahigh SERS enhancement factor of 1.07 × 107 for non-resonant Raman probe, with excellent spectral reproducibility and stability. More meaningfully, the developed substrate can realize an ultrasensitive detection for different kinds of antibiotic residues in real river water, even a comprehensive identification for multicomponent residues. Moreover, TiO2−X facet heterojunction can also execute an efficient photocatalytic degradation for residue pollutants in actual water system. And, the developed multi-function substrate possesses an excellent recyclability not only in SERS detection but also in photocatalysis.

A workflow for the detection of antibiotic residues, measurement of water chemistry and preservation of hospital sink drain samples for metagenomic sequencing

Hospital sinks are environmental reservoirs that harbour healthcare-associated (HCA) pathogens. Selective pressures in sink environments, such as antibiotic residues, nutrient waste and hardness ions, may promote antibiotic resistance gene (ARG) exchange between bacteria. However, cheap and accurate sampling methods to characterize these factors are lacking. To validate a workflow to detect antibiotic residues and evaluate water chemistry using dipsticks. Secondarily, to validate boric acid to preserve the taxonomic and ARG ('resistome') composition of sink trap samples for metagenomic sequencing. Antibiotic residue dipsticks were validated against serial dilutions of ampicillin, doxycycline, sulfamethoxazole and ciprofloxacin, and water chemistry dipsticks against serial dilutions of chemical calibration standards. Sink trap aspirates were used for a 'real-world' pilot evaluation of dipsticks. To assess boric acid as a preservative of microbial diversity, the impact of incubation with and without boric acid at ∼22°C on metagenomic sequencing outputs was evaluated at Day 2 and Day 5 compared with baseline (Day 0). The limits of detection for each antibiotic were: 3μg/L (ampicillin), 10μg/L (doxycycline), 20μg/L (sulfamethoxazole) and 8μg/L (ciprofloxacin). The best performing water chemistry dipstick correctly characterized 34/40 (85%) standards in a concentration-dependent manner. One trap sample tested positive for the presence of tetracyclines and sulphonamides. Taxonomic and resistome composition were largely maintained after storage with boric acid at ∼22°C for up to five days. Dipsticks can be used to detect antibiotic residues and characterize water chemistry in sink trap samples. Boric acid was an effective preservative of trap sample composition, representing a low-cost alternative to cold-chain transport.

A Europium Metal-Organic Framework and Its Polymer Composite Membrane as Switch-Off Fluorescence Sensors for Antibiotic Detection in Lake Water.

The detection of antibiotic residues is of great significance in monitoring their overuse in healthcare, livestock and poultry farming, and agricultural production. Herein, EuCl3 and 4,4'-dicarboxyl-diphenoxyethene (H2DPOE) ionothermally reacted in 1-methyl-3-butylimidazolium chloride to give a europium metal-organic framework (Eu-DPOE). Eu-DPOE shows different fluorescence quenching rates for sensing eight antibiotics under different excitation wavelengths. Eu-DPOE displays a fast response, high selectivity, and sensitivity in antibiotic detection by fluorescence quenching. Eu-DPOE can sensitively detect TCs (tetracyclines), NOR (norfloxacin), NFT (furazolidone), ODZ (ornidazole), SDZ (sulfadiazine), and CHL (chloramphenicol) with limits of detection below 0.5 μmol/L. It provides a convenient and rapid tool for sensing antibiotics in aqueous solution. The detection mechanism is a competition absorption between DPOE2- and antibiotics with the supports from powder X-ray diffraction (PXRD), UV-vis spectra, and fluorescence lifetime. With a composite membrane of poly(vinylidene fluoride) (PVDF) matrix loading Eu-DPOE (Eu-DPOE@PVDF), Eu-DPOE@PVDF exhibits a visual fluorescence response to NOR under a 254 nm UV lamp and NFT and CTC under 365 nm. Eu-DPOE@PVDF is applied in the quantitative detection of CTC, NOR, and NFT in lake water with recovery rates ranging from 88.37 to 113.8%. Totally, fluorescence-quenched Eu-DPOE@PVDF exhibits a fast response, high selectivity, and sensitivity in sensing CTC, NOR, and NFT.

Colloidal SERS measurement of enrofloxacin with petaloid nanostructure clusters formed by terminal deoxynucleotidyl transferase catalyzed cytosine-constituted ssDNA.

We developed petal-like plasmonic nanoparticle (PLNP) clusters-based colloidal SERS method for enrofloxacin (EnFX) detection. PLNPs were synthesized by the regulation of single-stranded DNA composed of homo-cytosine deoxynucleotides (hC) catalyzed by terminal deoxynucleotidyl transferase. SERS hot spots were created via the agglomeration process of PLNPs by adding an inorganic salt potassium iodide solution, in which EnFX molecules were attached to the negatively charged PLNPs surface by electrostatic interactions. This approach enabled direct in situ detection of antibiotic residues, achieving a limit of detection (LOD) of 1.15μg/kg for EnFX. The spiked recoveries of the SERS method were approximately 92.7% to 107.2% and the RSDs ranged from 1.05% to 7.8%, indicating that the method can be applied to actual sample detection. This colloidal SERS measurement platform would be very promising in various applications, especially in real-time and on-site food safety screening owing to its rapidness, simplicity, and sensitivity.

Fabrication of Au@MIL-101 (Fe) nanocomposite as highly sensitive SERS substrate for trace detection of sulfapyridine

This paper reports a two-step method for preparing a metal-organic framework (MOF) MIL-101 (Fe) based substrate with high sensitivity and stability for surface-enhanced Raman scattering (SERS) analysis. Firstly, MIL-101 (Fe) nanoparticles were synthesized using a traditional solvothermal method. Next, gold nanoparticles (AuNPs) were produced through a reduction method, and the AuNPs/MIL-101 (Fe) composite substrate was created by combining MIL-101 (Fe) with AuNPs. The adsorption capacity of the substrate and its SERS activity after multiple cleaning were tested. Using Rhodamine 6 G (R6G) as the probe molecule, the substrate's detection capability reached 10-8 M, with a relative standard deviation (RSD) of approximately 13.15%, indicating excellent SERS performance and uniformity. The ideal detection capability for sulfapyridine using the composite matrix can be as low as 10-6 M. This proposed substrate is convenient and efficient, holding great potential for the rapid and sensitive detection of antibiotic residues and other environmental pollutants.

Photochemical decoration of gold nanoparticles on MoS2 nanoflowers grafted onto the flexible carbon cloth as a recyclable SERS sensor for the detection of antibiotic residues on curved surfaces

Surface-enhanced Raman spectroscopy (SERS)-based flexible substrate has recently been demonstrated to be effective in detecting molecules on curved surfaces, however a suitable method for fabricating the flexible SERS substrate still remains a hurdle. In this paper, we fabricated a flexible SERS substrate by anchoring the plasmonic gold nanoparticles (Au-NPs) onto the hydrothermally grown flower-like molybdenum disulfide (MoS2) grafted onto carbon cloth (CC) via a facile photoreduction route. Benefitting from the abundant hotspots generation of the Au-NPs and photo-induced charge-transfer ability of MoS2, the constructed Au-NPs/MoS2/CC substrate exhibit a superior SERS sensing ability, excellent SERS enhancement factor, high flexibility and mechanical stability towards the nitrofurantoin (NFT) with an ultra-low detection limit of 10−11 M. As a trial for practical applications, the flexible substrate was used to detect NFT (10−4 M) in the curved surfaces of meat samples via swab technique. The ability of the flexible Au-NPs/MoS2/CC substrate to sustain the robust Raman signals of NFT even after recycling up to 4 cycles validated its reusability. The proposed flexible SERS substrate with reusable capability indicates its great potential in practical applications for the detection of target molecules on the curved surfaces.

Detection of veterinary antibiotic residues in fresh fecal samples collected from selected pig farms in the City of Baybay, Leyte, Philippines

Investigations on the presence of antibiotic residues in livestock manure are becoming an integral part on the quest against antimicrobial resistance (AMR). Moreover, as a potential hazard to human health and the environment, the threat of antibiotic residues cannot be taken lightly. As one of the biggest pig producers in Eastern Visayas, the Province of Leyte, Philippines is presented with the challenge to sustain the pork requirements of the region despite its limited overall production. This study aims to determine the prevalence of antibiotic residues present in the swine manure among selected commercial piggery farms in Baybay City, Leyte. Using147 fecal samples collected from different classes of pigs and following standard microbial inhibition plate technique, this study consistently found inhibitory action against the growth of Bacillus subtilis across three pH levels from fecal samples collected from grower-finishers, and breeders unlike samples collected from both the lactating and farrowing sows. These results may provide insights and baseline information useful for similar studies on antibiotic residues in meat and meat products that may have implications on human health.