中文摘要：

采用柱前衍生高效液相色谱法,监测实验室培养条件下中肋骨条藻藻体及培养液中游离态腐胺、精胺和亚精胺含量的变化,发现中肋骨条藻体内的游离态多胺主要为腐胺和亚精胺及少量的精胺。细胞中三者的含量在培养过程中一直增加,尤其是进入消亡期的腐胺和亚精胺含量骤增,这可能与胁迫条件下控制多胺合成的基因超表达有关。腐胺与亚精胺含量的比值与藻密度呈显著正相关（R2=0.775 1,p=0.049）,可以反应细胞生长周期的变化。精胺与亚精胺含量比值的变化早于藻密度,反应出多胺在细胞生长过程中的调节作用。培养液中的游离态多胺主要为腐胺,其次是亚精胺和精胺。中肋骨条藻可以吸收水体的腐胺和精胺。指数增长期内,藻细胞代谢旺盛会向环境中释放腐胺,因进入消亡期藻体大量死亡,降解释放使水体多胺含量升高。

英文摘要：

The concentration of free putrescine （Put） ,spermidine （Spd） and spermine （Slam） in the body and in the culture me dium during the growth cycle of Skeletonema costatum was measured by HPLC. Putreseine and spermidine are the main free polyamine in Skeletonema costatum,with lower content of spermine. The higher rate of increase in the content of polyamines in Skeletonerna costaturn in decline phase may be due to polyamine biosynthetic genes overexpressing under the sress. The ratios of Put/Spd in Skeletonema costatum have a positive relationship with the cell density （R2 = 0. 775 1, p = 0. 049 ）, which can show the changes of cell cycle. Changes in the ratios of Spm/Spd in Skeletonema costatum were followed by cell density, which is consistent with the idea that polyamines can regulate cell growth. The mainly free polyamine in the culture medium is putrescine, followed by spermidine and spermine. Skeletonema costatum can absorb the free polyamine from the culture medium and release the free polyamine into the medium in exponential growth phase owing to the exuberant metabolism of algae ceils. The massive dead algae would release free polyamine in decline phase and make the polyamine concentrations in the culture medium increase.