海藻中碘的化学种态研究Ⅰ

Determination of chemical species of iodine in algae Ⅰ

用化学分离结合中子活化法研究了海带、网翼藻、海黍子、松藻、石莼、礁膜和江篱7种海藻中总碘及水溶性碘、有机碘、I和IO3等不同形态碘的分布．研究结果表明：不同海藻中碘及其化学种态差别较大，海带中碘含量最高，达734×106（湿重），且99．2％的碘为水溶性碘．其他几种海藻中碘含量较低，且水溶性碘仅占16.5％～40．8％．海藻浸出液中碘主要以I的形式存在，占浸出总碘量的61．0％～92．7％，其次为有机碘占5．5％～37．4％，IO3含量最少，仅占1．4％～4．5％．该研究结果提示不同海藻的富碘机制可能不尽相同．从食用的角度看，其中碘的生物利用度也可能有较大的差异．

The chemical species of iodine in 7 marine algae Codium fragile, Ulva pertusa,Monostroma nitidum, Gracilaria con fervoides, Sargassum miyabei yendo,Dictyopteris divaricata and Laminara japonica were studied using neutron activation analysis combined with chemical separation. The contents of total iodine, water soluble iodine, organic iodine, I- and IO--3 in 7 algae were determined. The results indicate that the chemical species and contents of iodine in various algae are remarkably different. The highest iodine content of 734×10-6 (wet basis) was found in Laminara japonica,and with 99. 2% of total iodine beihg water soluble iodine. The iodine contents in other 6 algae are lower, and the soluble iodine makes up 16%-41% of the total. In the aqueous leachate, iodine is mainly I-, which amounts to 61% ~ 93% of total water soluble iodine, the percentages of organic iodine make up 5. 5%~37. 4%. The content of IO3 is the lowest, which is 1. 4 % ~4. 5 % of total iodine.,Thee suggest that the mechanism of iodine enrichment is possibly different for various algae,and its bioavailability varies as well.