盐度胁迫下中肋骨条藻和东海原甲藻的生长及内源多胺含量的变化

RELATIONSHIP BETWEEN GROWTH AND VARIATION OF ENDOGENOUS POLYMINE CONTENT UNDER SALINITY STRESS IN SKELETONEMA COSTATUM S. L. AND PROROCENTRUM DONGHAIENSE

在实验室内不同盐度梯度下培养常见的两种赤潮藻——中肋骨条藻(Skeletonema costatum s.l.)和东海原甲藻(Prorocentrum donghaiense),根据logistic生长模型获得了终止生物量Bf和最大生长速率μmax,并测定了藻体中过氧化物酶(POD)、二胺氧化酶(DAO)、多胺氧化酶(PAO)的活性和丙二醛(MDA)、腐胺(Put)、亚精胺(Spd)、精胺(Spm)的含量。结果表明,高、低盐度胁迫下,两种藻均会积累MDA,活性氧自由基的伤害增强,藻的生长受到了抑制。同时,两种藻都会提升多胺含量,通过多胺的调节作用来缓解胁迫的伤害,促进生长,但是在提升的多胺种类和形态上,两种藻存在着差异。高盐胁迫下,中肋骨条藻会提升多胺尤其是游离态多胺的含量来缓解伤害,东海原甲藻则依靠结合态的亚精胺和游离态的精胺的调节作用。低盐胁迫下,中肋骨条藻会提升游离态腐胺的含量,而东海原甲藻体内各形态的多胺都会上升。

We carried out a laboratorial cultivation experiment on two common HAB algae(Skeletonema costatum s.l. and Prorocentrum donghaiense) under different salinities to determine the activities of POD(peroxidase), DAO(diamine oxidase), and PAO(polyamine oxidase), and the contents of MDA(malondialdehyde), Put(putrescine), Spd(spermidine), and Spm(spermine) extracted from algae cells. The final biomass and maximum growth rate of the HAB algae were obtained in logistic growth model. The results show that the both algae can accumulate MDA under high or low salinity stress, indicating that damage by free radical of active oxygen increased and the algae growth were inhibited. Meanwhile, the two algae increased the polyamine content to relieve stress and promote growth. However, the type and form of polyamine were different. Under a high salinity stress, S. costatum s.l. can enhance the polyamine especially the content of free polyamine, while P. donghaiense relies mainly on the regulation of bound spermidine and free spermine. Under a low salinity stress, S. costatum s.l. would enhance the free putrescine, while in P. donghaiense, contents of all forms of polyamine would rise.