Abstract: A long-term used culture medium of Spirulina platensis was treated with different adsorbents, and they were screened in removal of the contained inhibitors via comparison of specific growth rate of Spiruina platensis in different adsorption-treated culture media. The concentrations of polysaccharide, organic acid and protein in culture medium before and after adsorption were compared, and the one with the largest concentration disparity was extracted to test its inhibition effect on Spirulina platensis growth. In addition, model analysis was carried out on the adsorption process. The results showed that the auto-growth inhibitor of Spirulina platensis was extracellular polysaccharide, and the adsorption treated culture medium by macro-porous adsorption resin S-8 could reduce extracellular polysaccharide content by 62% and simultaneously increased the specific growth rate by 39.4%, compared with the non-treatment medium. For the adsorption process of polysaccharide by S-8, 30 min was sufficient for equilibrium, pseudo-second-order and Boyd film diffusion model fitted well with the kinetic data, with linear correlation coefficients of 0.9991 and 0.9374, respectively.

Key words: Spirulina platensis, culture medium, auto-growth inhibitor, extracellular polysaccharide

摘要： 使用不同吸附剂吸附长期培养螺旋藻的藻液，通过比较螺旋藻在处理后的藻液中的比生长速率，筛选出能去除胞外自身生长抑制物的吸附剂；比较吸附前后藻液中多糖、有机酸和蛋白含量，提取出差别最大的物质，测试其对螺旋藻生长的抑制效应，并用数学模型对吸附过程进行分析. 结果表明，螺旋藻自身生长抑制物为胞外多糖，用大孔吸附树脂S-8处理藻液可使多糖含量降低62%，比生长速率提高39.4%；S-8对藻液中多糖的吸附30 min即可达到平衡，假二级动力学模型和Boyd液膜扩散模型与动力学实验数据拟合较好，线性相关系数分别为0.9991和0.9374.

关键词: 钝顶螺旋藻, 藻液, 自身生长抑制物, 胞外多糖