pH与氟对莱茵衣藻和蛋白核小球藻胞外碳酸酐酶活性及光合效率的影响

本文研究了不同pH（5.0、7.0和9.0）和F-浓度（0.1、1、10、50、100、200mmol·L-1）对莱茵衣藻和蛋白核小球藻的胞外碳酸酐酶活性、PSⅡ实际光合效率ΦPSⅡ和叶绿素a合成量的共同影响。结果表明：在低于1mmol·L-1的F-作用下,两种微藻的生理和生长指标主要受pH影响;酸性条件下,两种微藻胞外碳酸酐酶活性显著低于中性和碱性条件时,ΦPSⅡ随pH升高而增大,叶绿素a合成量随pH升高而增加。在高于1mmol·L-1的F-作用下,两种微藻的生理及生长指标受F-和pH共同影响,且F-的作用大于pH的作用,胞外碳酸酐酶活性随着F-浓度升高先增加后降低,同时随着pH下降而降低;ΦPSⅡ和叶绿素a合成量则随着F-浓度升高和pH下降而迅速下降。胞外碳酸酐酶活性、ΦPSⅡ和叶绿素a合成量都能够作为指示微藻受氟胁迫的指标,以微藻为材料除去自然界氟超标水体中的超标F-,理论上是可行的。

Effect of pH and Fluoride on Extracelluar Carbonic Anhydrase Activity and Photosynthetic Efficiency of Chlamydomonas Reinhardtii and Chlorella Pyrenoidosa

Chlamydomonas reinhardtii and Chlorella pyrenoidosa were cultured in SE media at three pH levels（5.0,7.0,9.0） with added fluoride（NaF） of six concentrations（0.1,1,10,50,100 and 200 mmol·L-1）,and extracelluar carbonic anhydrase activity,photosynthetic efficiency and chlorophyll-a content of the two microalgaes were determined.The results indicated that physiologic activity and growth factors of the two microalgaes were mainly affected by pH rather than fluoride under the combinion of pH and less than 1 mmol·L-1 fluoride.Extracelluar carbonic anhydrase activity of the two microalgaes was significantly lower under acidic media than under neutral and alkaline media.ΦPSⅡ and chlorophyll-a synthesis of the two microalgaes decrease with pH descending.Physiologic activity and growth factors were significantly affected by the combination of pH and more than 1mmol·L-1 fluoride concentration.Extracelluar carbonic anhydrase activity first increased and then decreased until disappear with fluoride concentration increasing.The ΦPSⅡ and chlorophyll-a synthesis decreased with pH descending.Extracelluar carbonic anhydrase activity,ΦPSⅡ and chlorophyll-a synthesis can indicate whether microalgaes suffer from adversity.Physiologic activity and growth factors of Chlamydomonas reinhardtii and Chlorella pyrenoidosa are better under alkaline environment than under neutral and acidic environment.The results also indicated it＇s theoretically feasible to remove excessive fluoride in rich-fluoride water using microalgaes.