海産魚によるCoの蓄積

抄録

To know the effect of chemical forms of Co on its accumulation by marine fish, the accumulation and excreton of Co by the organism were observed using ⁶⁰CoCl₂ and ⁵⁷Co cyanocobalamin. The biological half life of the long component of ⁶⁰CoCl₂ was 166 days, and that of ⁵⁷Co cyanocobalamin was 43 days at 15°C. The concentration factor at the steady state was calculated as 32 for 60CoCl₂ and 3 for ⁵⁷Co cyanocobalamin. The higher concentration factro of ⁶⁰CoCl₂ than ⁵⁷Co cyanocobalamin was characteristic in comparison with other marine organisms. The distribution (%) of ⁵⁷Co cyanocobalamin in the liver was three times higher than that of ⁶⁰CoCl₂.
It was estimated from the gel filtrations on Sephadex G-75 and Sepharose CL-4B that ⁶⁰Co combined with five constituents in the liver of Acanthopagrus schlegeli and Chasmichthys gulosus, and with two constituents in the liver of Girella punctata. The gel filtration profiles of ⁵⁷Co cyanocobalamin in the liver of C. gulosus was similar to those of ⁶⁰Co. These constituents were considered to be protein by referring to the optical density at 280nm. A constituent with a molecular weight of 2×105 wh ch combined with Co was characteristic in livers of fish among the marine organisms.