四环素类抗菌药物在鸡粪中的降解研究

Degradation of Tetracyclines in Chicken Feces

采用高效液相色谱法,研究了不同光照条件对鸡粪中土霉毒(OTC)和金霉素(CTC)降解动态的影响。试验分为两组,一组含药鸡粪置于避光条件,另一组置于室外自然光条件下。分别在第0、0.5、1、2、3、5、7、9、12、15d对两组鸡粪取样、检测和分析。结果表明,避光条件下,鸡粪中OTC3个初始浓度在15d内降解幅度分别为5.67%、6.05%和7.61%;CTC降解幅度分别为5.93%、6.20%和7.36%;而在自然光照条件下,OTC降解幅度分别达到87.60%、95.66%和97.81%,CTC分别达到89.53%、95.98%和98.62%,且鸡粪中OTC、CTC的浓度随时间变化趋势符合一级动力学方程Ct=C0e-kt,鸡粪中OTC、CTC的降解半衰期分别为(4.11±1.17)d和(3.24±1.02)d。结果表明,OTC和CTC都具有光解的特性,且鸡粪中CTC光解速率比OTC快。

The effects of light on degradation of chloroteracycline （CTC） and oxytetmcyline（OTC） in chicken feces was studied, and the degradation velocity of CTC and OTC was determined by HPLC. The chicken feces were randomly assigned into two groups. One was in photophobic condition and the other was exposed to light. Samples were respectively collected from the two groups on day 0, 0.5, 1, 2, 3, 5, 7, 9, 12, 15 and analyzed by HPLC. In photophobic condition, the degradation velocity of three levels of OTC and CTC in chicken feces were 5.67%, 6.05%, 7.61% and 5.93%, 6.20%, 7.36% respectively within 15 days, while, in natural light, they were 87.60%, 95.66%, 97.81% and 89.53%, 95.98%, 98.62% respectively. Degradation velocity of CTC and OTC in chicken feces were similar, which consisted with the first order kinetic equation Ct=C0e^-kt. The half-lives of CTC and OTC in chicken feces were （3.24～1.02）d and （4.1 1±1.17）d respectively in natural light. The results indicated CTC and OTC had photolytic characteristics, and the photolysis speed of CTC was higher than that of OTC in chicken feces.