克伦特罗在猪体内立体选择性降解行为研究

Study on the stereochemical degradation of clenbuterol in swine edible tissues

关键词:  克伦特罗  手性对映体  液相色谱串联质谱法  立体选择性降解

Key words:  clenbuterol  enantiomers  liquid chromatography with tandem mass spectrometry  stereochemical degradation

摘要:

为了解克伦特罗在猪体内是否存在立体选择性降解行为,本研究通过手性分离制备了克伦特罗单一对映体,然后对生猪进行饲喂含有克伦特罗外消旋体(2.0 mg/kg)和单一对映体(1.0 mg/kg)的饲料,7d后进行屠宰,定期采集猪的肌肉、肝脏、肾脏、心脏、肺脏和尿液,测定克伦特罗对映体含量。研究发现,克伦特罗在猪体内存在立体选择性降解行为,肝脏、肾脏和肺脏中对映体(右旋体/左旋体)比例较高,心脏和肌肉中的对映体比例相对较低；休药3d时,肝脏、肾脏、猪尿中的对映体比例均处于最高点。同时发现,克伦特罗对映体在猪体内不存在相互转化现象。该研究为科学评估动物性食品残存的克伦特罗对人体健康造成的危害提供了科学依据。

Abstract:

Two single enantiomers had been acquired by chiral separation to investigate whether there is a stereochemical degradation behavior in swine tissues for clenbuterol. Then, experiments were carried out in swine by feeding diets with 2.0 mg/kg of clenbuterol and 1.0 mg/kg of its single clenbuterol enantiomer for consecutive 7 days, respectively. After 7 d, the swine tissues (muscle, heart, lung, liver and kidney) and urine samples were collected regularly, and the content of clenbuterol enantimers had been determined by LC-MS/MS. After residual data analysis, there is stereochemical degradation behavior in swine tissues for clenbuterol. The ratio of ( ) stereoisomer/(-) stereoisomer is higher than 1.5 for most of liver, lung and kidney samples when the swine had been fed with clenbuterol diets; and the ratio of ( ) stereoisomer/(-) stereoisomer is between 0.8 and 1.25 for muscle and heart samples. For liver, kidney and urine samples, the ratio of ( ) stereoisomer/(-) stereoisomer is highest at 3 d interval. Moverover, there is not mutual transformation for clenbuterol enantiomer in swine tissues. Finally, the carry out the experiment provide scientific basis for scientific assessment of damage of residual clenbuterol in animal derived food.