著者

中川 満夫 村田 剛 下川 晃彦 本田 俊哉 児島 昭次 内山 充

出版者

公益社団法人日本薬学会

雑誌

衛生化学 (ISSN:0013273X)

巻号頁・発行日

vol.30, no.5, pp.301-308, 1984-10-31

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The methods for analyzing residual methylene blue and malachite green in the muscle and liver of rainbow trout and eel were established. Since methylene blue and malachite green in the muscle and liver homogenates were effectively extracted by n-butanol in the presence of ZnSO_4,the recoveries of methylene blue and malachite green were determined by measuring the optical density (665 nm for methylene blue, 620 nm for malachite green) of butanol solution extracted from the liver and muscle homogenates containing the dyes. However, the optical density of malachite green in butanol solution extracted from the liver homogenates was measured at 500 nm, 620 nm and 700 nm, and was then calculated from the following equation ; Net OD_<620>=(MOD_<620>-OD_<700>)-[(OD_<500>-OD_<700>)×0.4815-0.0033] MOD_<620> : OD observed at 620 nm : malachite green + pigments of liver homogenates The recoveries of methylene blue and malachite green added to the muscle homogenates were 80-87% and 80-88%, respectively. The limits of detection in the muscle were 0.1 μg/g for both dyes. Also, the recoveries of methylene blue and malachite green added to the liver homogenates were approximately 85-87% and 88-95%, respectively. As little as 0.5 μg/g of both dyes in the liver was detectable. On the other hand, when rainbow trout were exposed to 0.5,1.0 and 2.0 ppm of malachite green solution at 16℃ for 1 h, residual amounts of malachite green in the muscle and liver were 1.41±0.28 μg/g (muscle) and 5.9±1.2 g/g (liver), 2.41±0.11 μg/g (muscle) and 10.1±1.4 μg/g (liver), and 5.90±1.61 μg/g (muscle) and 19.1±2.8 μg/g (liver), respectively. Also, when eel were exposed to 3.0 ppm of methylene blue solution at 16℃ for 1,2 and 3 h, residual amounts of methylene blue in the liver was 1.20±0.3 μg/h, 1.10±0.5 μg/2 h and 0.90±0.2 μg/3 h, respectively, and residual methylene blue in the muscle could not be detected.