中文摘要：

目的：以水产加工下脚料鳕鱼骨为原料,探讨鳕鱼骨活性钙的最佳制备条件,并对其生物利用度进行研究。方法：对鱼骨进行基本组成分析与组织学观察;采用正交试验确定鱼骨活性钙的最佳提取条件;采用低钙饮食建立大鼠缺钙模型,检测大鼠血清生化指标、骨钙含量及钙代谢指标,对鱼骨活性钙的生物利用度进行探讨。结果：鳕鱼骨中钙与磷含量分别达到207.8 mg/g和100.9 mg/g,其比值接近2∶1。扫描电镜观察发现鳕鱼骨表面具有坚固致密的扁平板状羟基磷灰石结晶。活性钙最佳提取条件为提取温度100℃、提取时间120 min、酸混合比例（柠檬酸-苹果酸体积比）1∶2、酸质量分数15%,在此条件下提取率达到96.15%。与空白对照组相比,活性钙各剂量组能显著提高大鼠骨钙含量。钙代谢实验测定结果显示,活性钙高剂量组钙吸收率显著高于相同钙水平的碳酸钙对照组。结论：鳕鱼骨可作为一种优良的天然钙源,鱼骨活性钙能够作为一种有效的钙营养强化剂加以开发。

英文摘要：

Objective： To determine the optimum conditions for the preparation of active calcium from cod bone through orthogonal array experiments and to investigate its bioavailability. Methods： Compositional analyses and histological observation of cod bone were performed. The optimum parameters for preparng active calcium from cod bone were obtained by orthogonal array experiments. The calcium defi ciency model in rats induced by low-calcium diet was used to investigate the calcium bioavailability by detecting the contents of serum calcium and bone calcium and the indicators of calcium metabolism. Results： The contents of calcium and phosphorous in cod bone were 207.8 mg/g and 100.9 mg/g, respectively, indicating a ratio of approximately 2：1 between the two elements. Tightly and firmly combined hydroxyapatite crystals characterized by the fl at tabular shape were found under scanning electron microscopy（SEM） observation. The optimum acid extraction conditions for active calcium from cod bone were determined as follows： extraction temperature, 100 ℃; extraction time, 120 min; ratio of citric to malic acid, 1：2; and acid concentration, 15% leading to a calcium yield of 96.15%. Compared with the blank control group, the active calcium at all doses investigated exhibited signifi cantly higher contents of femur calcium. The results of calcium metabolism experiments suggested that the calcium absorption of high dose group was signifi cantly higher than that of calcium carbonate group. Conclusions： These results demonstrate that cod bone is a good calcium resource and the active calcium extracted from cod bone possesses excellent bioavailability and could be used as a natural calcium supplement.