孔雀石绿及其主要代谢产物在欧洲鳗鲡肌肉中的蓄积及消除规律

Accumulation and elimination of malachite green and its primary metabolite in juvenile European eels (Anguilla anguilla) muscle

为了解孔雀石绿及其有毒代谢产物无色孔雀石绿在鱼体中的蓄积与消除规律,达到对孔雀石绿的禁用监控,本试验对初始体重为(12.42±2.18)g的欧洲鳗鲡进行0.1 mg.L-1和0.2 mg.L-1浓度(P1和P2组)孔雀石绿药浴24 h,再转移到清水中养殖120 d,采用高效液相色谱法测定肌肉组织中孔雀石绿及无色孔雀石绿的残留。在药浴过程中,鳗鲡肌肉组织中孔雀石绿平均含量不断升高,P1和P2组分别于药浴12 h和24 h达到最高值(720.5±192.6)μg.kg-1和(1404.8±421.9)μg.kg-1;在清水养殖过程中,孔雀石绿在鳗鲡肌肉中含量波动式下降,并于水浴2160 h(90 d)时两个处理组都低于检测限度。肌肉中所含无色孔雀石绿,在药浴过程以及清水养殖的开始一段时间内不断升高,P1和P2组分别于水浴的72 h和120 h达到最高值(960.1±251.0)μg.kg-1和(1 625.8±183.2)μg.kg-1,然后呈波动式下降,至实验结束(水浴120 d)时两个实验组肌肉中还有一定残留。结果表明,无色孔雀石绿的代谢消除时间较长,可以作为检测的标志物。另外,不同浓度的孔雀石绿在鳗鲡肌肉中的代谢规律相似,只是随药浴浓度升高,肌肉中孔雀石绿和无色孔雀石绿含量最高值出现时间有所滞后,以及消除时间相对延长。

The depletion of malachite green （MG） and its primary metabolite poisonous leuco-malachite green （LMG） was followed for 120 days in juvenile European eels （Anguilla anguilla）, in order to investigate residues of MG and to monitor the use of MG in fish. The eels at an average weight of （ 12.42 ±2.18） g were exposed to MG at a nominal concentration of 0.1 mg · L ^-1 and 0.2 mg · L ^-1（ named P1 and P2 group） bath water for 24 h respectively, at a water temperature varying between 20.0 and 21.0 ℃. After treatment, the juvenile fish were transferred into a tank containing MG free water. At regular time intervals, 9 fish muscle were collected for high-performance liquid chromatography （HPLC） analysis. The highest average concentration of MG green was found at （720.5 ±192.6） μg·kg^-1 muscle tissue at 12 h in group P1, and （1 404.8 ±421.9） μg·kg^-1 muscle tissue at 24 h after the start of the treatment in group P2, respectively. The LMG metabolite concentrations were relatively high. Seventy two hours after the end of the treatment with a maximum averaged concentration at （960.1 ±251.0） μg·kg^-1 muscle tissue in group P1, and 120 h with a maximum （1 625.8 ±183.2） μg·kg^-1 in group P2. At 2880 h （120 d） after exposure, LMG was still present at an average level of 7.6 μg·kg^-1 muscle tissue. The parent drug MG was not detectable at the last analysis points 2 160 h and 2 880 h after treatment. So leuco-malachite green （LMG） was very slowly eliminated from the muscle tissue and can be used as a target analysis in residue monitoring programs. The results also indicated that the law of accumulation and elimination of MG and LMG in eel muscle was same, but maximum of MG and LMG appeared later in higher concentration treatment fish, when the MG exposed concentrations were different.