溶藻细菌BS01产二异丁氧基苯基对塔玛亚历山大藻生长的影响

Abstract

【目的】利用一株溶藻细菌bS01分泌的杀藻化合物(二异丁氧基苯基)胺作用于赤潮藻——塔玛亚历山大藻(AlEXAndrIuM TAMArEnSE),研究该化合物对塔玛亚历山大藻的作用效果及可能的作用机制。【方法】利用10和20μg/M l的杀藻化合物处理塔玛亚历山大藻,观察藻细胞的响应。【结果】研究发现,利用20μg/M l的杀藻化合物处理藻,24 H后杀藻率达到84.1%,此时细胞内叶绿素A的含量仅为对照的58.5%。而当对藻细胞最大光化学效率(fV/fM)进行测定时发现,20μg/M l的浓度处理24 H后,最大光化学效率相比于对照细胞降低了55.5%,这说明藻细胞的光合作用过程受到抑制。细胞内部的活性氧(rOS)水平在处理0.5 H后即开始增高,并导致细胞内部的脂质过氧化,使细胞内丙二醛(MdA)的含量上升。藻细胞的抗氧化酶如超氧化物歧化酶(SOd)和过氧化氢酶(CAT)的活性也有不同程度的增高,以清除细胞内部的活性氧。利用透射电镜观察发现,20μg/M l的浓度处理24 H后,细胞内重要的细胞结构解体,细胞严重空泡化,显示出细胞死亡的特征。【结论】杀藻化合物(二异丁氧基苯基)胺能够通过引起藻细胞内部氧化损伤的方式引起藻细胞的死亡,同时该化合物仅针对少数几种藻类具有杀藻效果,因此该杀藻化合物在赤潮的治理方面具有较好的应用前景。

[Objective] A strain named BS01 showed strong algicidal activity to Alexandrium tamarense and we got algicidal compound( 2-isobutoxyphenyl) amine from BS01 to study its algicidal effect on A.tamarense.[Methods] We studied the algicidal mechanism of( 2-isobutoxyphenyl) amine on photosynthetic process,antioxidant enzyme activities and morphological change of A.tamarense.[Results] After 24 hours treatment with( 2-isobutoxyphenyl) amine,algicidal activity was 84.1% with the concentration of 20 μg / m L.The compound could induce a reactive oxygen species burst in P.globosa in 0.5 hours which could cause serious oxidative damage to algal cells.The Fv/ Fmvalue which could reflect photosystem II( PS II) electron flow status also decreased.To eliminate the excess ROS,the activities of the antioxidant systems( including superoxide dismutase and catalase) increased significantly during exposure.Transmission electron microscope analysis showed obvious morphological modifications of chloroplast dismantling as a part of the algicidal process.[Conclusion] These results indicated that the lysis mechanism of algicidal compound on algae may primarily be the increasing level of ROS in the algal cells.