摘要
初步研究了培养基中氮浓度及补加氮对塔玛亚历山大藻毒素产量的影响.低氮(88.2μmol/L)条件下藻细胞具有较高的比生长速率(0.60d?1),是高氮(882μmol/L)下的约1.2倍.低氮下在藻细胞对数生长的末期(第10天)补加氮(至高氮水平)导致塔玛亚历山大藻的最大细胞密度(48.5×103mL?1)明显增加,分别是低氮(6.28×103mL?1)和高氮(21×103mL?1)下的7.7和2.3倍;最大单位细胞毒素含量(1.26pg/cell)和产量(43.51μg/L)分别是低氮(1.09pg/cell和6.49μg/L)和高氮(0.88pg/cell和13.18μg/L)下的1.2,1.4倍和6.7,3.3倍.结果显示,在培养基中低水平氮、磷条件下塔玛亚历山大藻细胞的毒素合成增加,其中特别是磷限制条件下,藻细胞的毒素含量增加更为显著.通过低氮下补加氮源以维持培养基中的低氮水平,可以显著促进塔玛亚历山大藻细胞的毒素产量.
The influence of nitrate concentration on toxin content ofAlexandrium tamarense was investigated, which gave rise to the supply of an appropriate nutrition condition and culture technique of increasing the toxin production ofAlexandrium tamarense. Low nitrate level （88.2μmol/L） resulted in higher specific growth rate, which was 1.2 times of that at high nitrate level （882 μmol/L）. When cultures at low nitrate level were supplemented with nitrate at 793.8 μmol/L in late exponential growth phase, the highest cell density（48.5×10^3 mL^-1） was drastically enhanced, which was 7.7 and 2.3 times of those under low （6.28×10^3 mL^-1） and high （21×10^3 mL^-1）nitrate conditions, meanwhile the highest toxin content and production were 1.26 pg/cell and 43.51 μg/L, which were 1.2 and 1.4 or 6.7 and 3.3 times of those under low and high nitrate conditions respectively. The results showed that toxin content of Alexandrium tamarense was enhanced at low nitrate and phosphate levels, and in particular toxin content increased significantly under limited-phosphate conditions. The supplementation of nitrate under low nitrate condition to maintain low level of nitrate contributed to the effective increase of toxin production of Alexandrium tamarense.
出处
《过程工程学报》
CAS
CSCD
北大核心
2005年第4期438-441,共4页
The Chinese Journal of Process Engineering
基金
国家重点基础研究发展规划(973)资助项目(编号:2001CB409706)
国家自然科学基金资助项目(编号:20176060)
