[Inspection of Residual Veterinary Drugs at Tokyo Metropolitan Institute of Public Health: Bioassay and LC-MS/MS Analysis].

Veterinary drugs are used worldwide to prevent and treat diseases and promote growth in animals, fisheries, and beekeeping. Despite their effectiveness, the illegal and improper use of these drugs can result in livestock and fishery products, potentially impacting human health by causing allergic reactions, cytotoxicity, and antimicrobial resistance. To mitigate these adverse effects, the Japanese government established a positive list system in 2006.

Monitoring of residual antibacterial agents in animal and fishery products in Tokyo from 2003 to 2019: application and verification of a screening strategy based on microbiological methods.

Residual antibacterial agents in 5909 animal and fishery products in Tokyo, Japan, were investigated over 17 consecutive years (2003-2019). Monitoring of 32 antibacterial agents (lincosamides, macrolides, penicillins, quinorones and tetracyclines) per product was accomplished via two steps: screening (by microbiological methods) and confirmation (by instrumental methods). Microbiological screening methods identified presumptive groups and determined semi-quantitative values.

[Prevalence of Cereulide-Producing Bacillus cereus in Pasteurized Milk].

To recognize the risk of Bacillus cereus in pasteurized milk, we investigated the prevalence of B. cereus and the rate of the production of cereulide from B. cereus isolates.

Short-Term Effects of Salt Restriction via Home Dishes Do Not Persist in the Long Term: A Randomized Control Study.

Salt intake reduction is crucial to prevent non-communicable diseases (NCDs) globally. This study aimed to investigate the short- and long-term effects of monitoring salt concentration in homemade dishes on reducing salt intake in a Japanese population. A double-blind randomized controlled trial using a 2 × 2 factorial design with two interventions was conducted in 195 participants; they were assigned to both interventions for a group monitoring salt concentration in soups (control: no monitoring) and a group using low-sodium seasoning (control: regular seasoning).

[Determination of Antibacterial Agents for Animals in Swine Muscles by Microbiological Screening and LC-MS/MS].

The determination of antibacterial agents for animals in swine muscles was improved by microbiological screening and liquid chromatography-mass spectrometry (LC-MS/MS) analyses. In the first instance, the residual drugs were extracted from the samples using the NaEDTA-McIlvaine buffer (pH 6.0).

[Determination of Antifungal Drugs in Fish and Livestock Products Using LC-MS/MS].

We developed an analytical method for determining 15 antifungal drugs, 2 antiparasitic drugs, and 3 veterinary drugs in fish and livestock products using LC-MS/MS. First, 50% ethanol was added to their products, and the mixture was homogenized to reduce drug degradation. Thereafter, 20 drugs were extracted from the pretreated sample mixture using acetonitrile.

Quantification of staphylococcal enterotoxin type A in cow milk by using a stable isotope-labelled peptide via liquid chromatography-tandem mass spectrometry.

In this study, the staphylococcal enterotoxin type A (SEA) contaminant was quantified in cow milk by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with the use of a stable isotope-labelled peptide of SEA as an internal standard. SEA was cleaned up in a two-step process that included pH control and trichloroacetic acid (TCA) precipitation. The pH control phase eliminated other proteins.

Identification and quantification of cereulide in cow's milk using liquid chromatography-tandem mass spectrometry.

In this study, the presence of cereulide in cow's milk was identified and quantified using our validated method with liquid chromatography-tandem mass spectrometry. Cereulide was concentrated using protein acid-precipitation and extracted from the precipitate by using acetonitrile twice. The combination of protein acid-precipitation and extraction sufficiently eliminated the matrix compounds from the milk and a further clean-up step utilising solid-phase extraction could be omitted.

Simultaneous determination of nine acaricides and two metabolites in comb honey by LC/MS/MS.

We developed a method for the simultaneous determination of acaricides in comb honey using LC/MS/MS. Because methods for honey analysis had not previously been applied to comb honey, we modified three techniques for sample preparation and LC/MS/MS conditions. First, we used a modified QuEChERS method that changed the extraction solution from ethyl acetate to acetonitrile.

Simultaneous determination of multi-class veterinary drugs in chicken processed foods and muscle using solid-supported liquid extraction clean-up.

We developed a simultaneous determination method for 37 veterinary drugs in two chicken processed foods (deep-fried chicken and non-fried chicken cutlet) and muscle via liquid chromatography-mass spectrometry. The veterinary drugs belong to 7 different classes, including 4 antifolics, 4 benzimidazoles, 5 macrolides, 7 polyethers, 2 quinolones, 7 sulfonamides, and 8 other classes. The samples were extracted with ethyl acetate followed by acetonitrile with salt and buffers extraction.

Simultaneous determination of amantadine, rimantadine, and memantine in processed products, chicken tissues, and eggs by liquid chromatography with tandem mass spectrometry.

A simultaneous determination of amantadine, rimantadine, and memantine in processed products (deep-fried chicken, fried chicken, fried quail egg, and grilled chicken) with liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed. This new method was also applicable for chicken tissue (muscle, liver, and gizzard) and eggs. The chromatographic separation was performed on a Kinetex XB-C18 core-shell technology column using a mobile phase of acetonitrile and 0.

Determination and surveillance of hydrocortisone and progesterone in livestock products by liquid chromatography-tandem mass spectrometry.

A simple analytical method for the determination of hydrocortisone and progesterone in bovine, swine, and chicken muscle and eggs was developed. Hydrocortisone and progesterone were extracted with acetonitrile and subsequently cleaned-up using an Oasis HLB mini-cartridge. The method was validated in accordance with Japanese guidelines and exhibited trueness from 86.

[Determination of Amantadine in Poultry Tissues and Egg by LC-MS/MS].

An accurate and selective analytical method for amantadine, which is used as antiviral drug to treat influenza A virus infection, was developed using LC-MS/MS. Residual amantadine was extracted from 4 kinds of food sample (poultry muscle, liver, gizzard and egg) with acetonitrile-pH 3.0 McIlvaine buffer (7 : 3), then cleaned up with an Oasis® MCX mini-cartridge.

Determination and surveillance of nine acaricides and one metabolite in honey by liquid chromatography-tandem mass spectrometry.

A simple and accurate analytical method for the determination of acaricides in honey was developed and validated in accordance with Japanese validation guidelines. Analytes - amitraz, N-2,4-dimethylphenyl-N-methylformamidine (DMPF), etoxazole, fenpyroximate, fipronil, hexythiazox, propargite, pyridaben and spirodiclofen - were extracted with ethyl acetate under basic conditions and subsequently cleaned up using an InertSep(®) MA-1 polymer-based anion-exchange column. The method was validated by fortified recovery tests at three different concentrations (1, 5 and 10 µg kg(-1)) performed with three samples daily on five different days.

Multi-residue Determination of Polar Veterinary Drugs in Livestock and Fishery Products by Liquid Chromatography/Tandem Mass Spectrometry.

Residues of 37 polar veterinary drugs belonging to six families (quinolones, tetracyclines, macrolides, lincosamides, sulfonamides, and others) in livestock and fishery products were determined using a validated LC-MS/MS method. There were two key points in sample preparation. First, extraction was performed with two solutions of different polarity.

Single-laboratory validation study of rapid analysis method for multi-class veterinary drugs in milk, fish and shellfish by LC-MS/MS.

A method of rapid analysis of multi-class residual veterinary drugs in milk, fish and shellfish was validated in accordance with Japanese guidelines for the validation of analytical methods for residual agricultural chemicals in food. Using LC-MS/MS, 43 multi-class veterinary drugs, including sulfonamides, quinolones, coccidiostats and antiparasites, could be analyzed in one injection. Analytes were extracted from samples with two kinds of solvent, acetonitrile containing 1 vol% formic acid and anhydrous acetonitrile, and salted out with 4.