水杨酸对铜绿微囊藻胞外多糖和微囊藻毒素含量的影响

Effect of salicylic acid on polysaccharide and microcystin contents in Microcystis aeruginosa PCC7806

目的研究在化感抑藻物质水杨酸(SA)作用下,铜绿微囊藻PCC7806胞外多糖(PS,包括胶鞘多糖CPS、可溶性胞外多糖EPS)和微囊藻毒素(MC-RR)的变化。方法 0、0.25、0.50、0.75和1.00 mmol/L SA加入对数期的铜绿微囊藻PCC7806培养液中,以硫酸苯酚法和液相色谱法,在第6 d和12 d分别测量PS和MC-RR的量,从单个细胞和培养液角度探讨SA对PS和MC-RR的影响。结果第6 d时,CPS随SA浓度增加而增多,第12 d时,CPS随SA浓度增加而减少。整个培养期间,培养液中EPS以及胞内MC-RR浓度随SA浓度增加而先增加后减少。结论SA作用初期铜绿微囊藻胞外多糖CPS和MC-RR含量增加以应对SA造成的胁迫,但后期胞内外MC-RR含量均有所下降。

Objective To study the variation of polysaccharide （PS） , which can be classified as capsule polysaccharide （EPS） and extracellular polysaccharide （EPS）, and microcystin-RR （MC-RR） content of Microsystis aeruginosa under the stress of salicylic acid （SA）. Methods 0, 0.25, 0.50, 0.75 and 1.00 mmol/L SA were added into the culture of M. aeruginosa at logarithmic phase and the contents of PS and MC-RR were quantified by phenol-sulfuric acid method and high performance liquid chromatography （HPLC） method in the 6th and 12th day. Meanwhile the effect of SA on PS and MC-RR contents were discussed at both the level of single cell and that of whole culture medium. Results CPS contents were increased with the increasing concentration of SA on the 6th day and decreases on the 12th day. The content of EPS and intracellular MC-RR first increases and then decreases with the increasing SA concentration in the whole stage. Conclusion The contents of CPS and MC-RR increase for the stress of SA in early days, and then the contents of MC-RR both inside and outside the cell are decrease.