铁在不同磷源条件下对铜绿微囊藻生长与产毒的影响

针对磷和微量元素铁对藻类生长的共同作用,研究不同磷源下藻细胞生长与产毒过程中磷与铁的共同作用特性。试验选用产毒铜绿微囊藻为藻种,以硝态氮为氮源,分别以磷酸氢二钾(K_2HPO_4)、小分子有机磷甘油磷酸钠(Na Gly)和大分子有机磷卵磷脂(LEC)为磷源,同步考察不同铁离子(Fe~(3+))浓度下藻类的生长与产毒表现。结果表明:K_2HPO_4和NaGly是藻细胞优先利用的磷源,在这两种磷源条件下,藻细胞的生长与产毒均得到促进,藻细胞平均粒径随培养时间保持稳定; LEC不利于藻细胞的生长与产毒,且藻细胞平均粒径波动较大。在对数增长期中,叶绿素a与胞内藻毒素(MC-LR)呈现正相关关系,在培养过程中藻细胞胞内总磷与藻液中总的碱性磷酸酶活性并未显现出相关性。不同磷源下微量元素铁对藻细胞的生长状况影响不同,NaGly与铁的协同作用更有利于藻细胞的生长与产毒。

Effect of iron on growth and toxicity in production of Microcystis aeruginosa under different phosphorus sources

Aiming at the interaction of phosphorus and trace element iron on the growth of algae, the interaction characteristics of phosphorus and iron in the growth and toxicity of algal cells were studied under different phosphorus sources. Microcystis aeruginosa was selected as algae species, and nitrate nitrogen was used as nitrogen source. Dipotassium hydrogen phosphate(K₂HPO₄), small molecular organic phosphorus sodium glycerophosphate(NaGly)and macromolecular organophosphorus lecithin(LEC)were used as phosphorus sources respectively. The growth and toxicity of algae under different iron(Fe³⁺)concentrations were simultaneously investigated. The results showed that K₂HPO₄ and NaGly were the phosphorus sources preferentially used by algae cells. Under these two phosphorus sources, the growth and toxicity of algae cells were promoted, and the average particle size of algae cells remained stable with the incubation time. LEC was not conducive to the growth and toxicity of algae cells, and the average size of algae cells fluctuated greatly. During logarithmic growth period, chlorophyll a was positively correlated with intracellular algae toxin(MC-LR), but there was no correlation between total intracellular phosphorus and total alkaline phosphatase activity(APA)in algae solution. The effect of trace element iron on the growth of algae cells was different under different phosphorus sources and the synergistic effect of NaGly and iron was more conducive to the growth and toxicity of algae cells.