Our study developed a quick method for confirmatory analysis of avermectins (abamectin B1a, doramectin, ivermectin B1a, eprinomectin B1a, and moxidectin) in bovine milk according to the European Commission Decision 2002/657/EC requirements. Avermectins were liquid-liquid extracted with acetonitrile, followed by an evaporation step, and then analyzed by liquid chromatography/electrospray ionization tandem mass spectrometry in the negative ion mode. An in-house method validation was performed and the data reported on specificity, linearity, recovery, limit of detection, limit of quantitation, decision limit, and detection capability. The advantage of this method is that low levels of avermectins are detectable and quantitatively confirmed at a rapid rate in milk.

In this study we have devoloped and validated a confirmatory analysis method for nitrofuran metabolites, which is in accordance with European Commission Decision 2002/657/EC requirements. Nitrofuran metabolites in honey, milk, poultry meat and fish samples were acidic hydrolised followed by derivatisation with nitrobenzaldehyde and liquid-liquid extracted with ethylacetate. The quantitative and confirmative determination of nitrofuran metbolites was performed by liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) in the positive ion mode. In-house method validation was performed and reported data of validation (specificity, linearity, recovery, CC_α and CC_β). The advantage of this method is that it avoids the use of clean-up by Solid-Phase Extraction (SPE). Furthermore, low levels of nitrofuran metabolites are detectable and quantitatively confirmed at a rapid rate in all samples.

The aim of this study was to determine the pharmacokinetics and pharmacodynamics of danofloxacin (DAN; 6 mg/kg) following subcutaneous administration alone or co-administration with meloxicam (MLX; 1 mg/kg) in healthy lambs and lambs with respiratory infections. The study was carried out using a total of four groups: HD (healthy; n = 6) and ID (infected; n = 7) groups who were administered DAN only, and HDM (healthy; n = 6) and IDM (infected; n = 7) groups who were administered DAN and MLX simultaneously. The plasma concentrations of DAN were determined using high-performance liquid chromatography–UV and analyzed by the non-compartmental method. DAN exhibited a similar elimination half-life in all groups, including both the healthy and infected lambs. The total clearance in the HDM, ID and IDM groups and volume of distribution in the HDM and IDM groups were significantly reduced. MLX in the IDM group significantly increased the area under the curve (AUC) and peak concentration (C_max) of DAN compared to the HD group. The Mannheimia haemolytica, Escherichia coli, and Streptococcus spp. strains were isolated from bronchoalveolar lavage fluid samples of the infected lambs. When co-administration with meloxicam, DAN at a 6 mg/kg dose can provide optimum values of ƒAUC_0–24/MIC (>56 h) and ƒC_max/MIC (>8) for susceptible M. haemolytica isolates with an MIC₉₀ value of 0.25 µg/mL and susceptible E. coli isolates with an MIC value of ≤0.125 µg/mL.

In recent years, the widespread use of neonicotinoids in agricultural areas has caused environmental pollution due to its lower toxicity to mammals. Honey bees, which are considered as biological indicators of environmental pollution, can carry these pollutants to the hives. Forager bees returning from sunflower crops that have been treated with neonicotinoids treated sunflower fields cause residue accumulation in the hives, which reason colony-level adverse effects. This study analyses neonicotinoid residues in sunflower (Helianthus annuus) honey sampled by beekeepers from Tekirdag province. Honey samples have been subjected to liquid-liquid extraction methods before liquid chromatography-mass spectrometry (LC-MS/MS). The method validation was carried out to fulfill all the necessary requirements of procedures SANCO/12571/2013. Accuracy was in the range of 93.63108.56, for recovery in the range of 63.04103.19, and for precision in the range 6.0312.77. Detection and quantification limits were determined according to the maximum residue limits of each analyte. No neonicotinoid residues were found above the maximum residue limit in the sunflower honey samples analysed.

Background: There are many active substances in the composition of the Hypericum perforatum L. plant that have different and complex structures and show different pharmacological effects. It was accepted as a medicinal plant by the World Health Organization in 2002, and it is given a detailed place in the monographs under the name Hyperici herba. In these monographs, the anti-bacterial, anti-viral, anti-depressant, protein kinase-C inhibitor, and wound-healing effects of the plant were described. Objectives: The aim of this study is to determine the essential oil components in the samples of the H. perforatum L. plant, which is widely grown in the Thrace region in Türkiye. Materials and Methods: H. perforatum L. plant growing naturally in the provinces of the Thrace region was collected, and the essential oils of the plant were obtained by using the hydro distillation method after the collected herbs were dried. Chemical content analyses were performed on a gas chromatography-flame ionization detection (GC-FID). Results: The main components of the essential oil of the plant are sesquiterpenes (ß-caryophyllene, caryophyllene oxide, β-selinene, α-selinene, β-farnesene, α-amorphene, spathulenol), alcohols (1-tetradecanol, 1-tridecanol, phytol, and alpha cadinol), and fatty acids (pentadecanoic acid, palmitic acid, and 9, 12 octadecadienoic acid). Conclusion: This is the first study to determine the chemical composition of essential oil in H. perforatum L. samples collected from the Thrace region in Türkiye. The essential oil content of the plant can be affected by factors such as the developmental stages of the plant (preblooming, flowering stage, and fruiting time), use of fresh or dry plant material, extraction method, genetic parameters, and climate.

This study provides insight into the development and validation of the simple, rapid and sensitive method of Liquid Chromatography-Tandem Mass Spectrometry for determining the residues of dexamethasone in bovine milk. The maximum residue limit for dexamethasone in bovine milk is 0.3 ng/ml⁻¹. Chromatographic separation was achieved on an Agilent Proshell 120 SB:C18 (2.7µm 100x3.0 mm) column. The bovine milk was extracted with ethyl acetate, and the evaporated elution was dissolved with hexane, water and methanol, and analyzed by the LC-MS/MS method. The mobile phase A was a solution of 5 Mm ammonium formate in water, while the mobile phase B was 0.1% formic acid in acetonitrile. The calibration graphics were prepared within the range of 0.15–0.6 ng/ml⁻¹, and a successful linearity was achieved (r ≥0.999). The limit of detection was 0.016 ng/ml⁻¹. The decision limit (CCα) and detection capability (CCβ) were 0.34 and 0.38 ng/ml⁻¹, respectively.