Effect of Pseudokirchneriella subcapitata (Chlorophyceae) exudates on metal toxicity and colloid aggregation.

摘要: Abstract The effects of Pseudokirchneriella subcapitata exudates on the acute toxicity metals (Cd, Cu, Pb and Zn) were studied using (1 h) algal photosynthesis inhibition tests. metal concentrations tested 30, 60, 120, 250 500 μg L −1 for Cd Zn; 500, 1000, 2000, 3000, 4000 μg L Cu Pb. It was established that P. markedly decreased toxicity. This effect ascribed to: (i) presence organic ligands bind reduce concentration free ionic metal, and/or (ii) interaction with cell surface a subsequent decrease in uptake. colloid aggregation also examined two different types single particle counters (SPC). Exudates facilitated removal, likely via acceleration (bridging). results clearly demonstrate play an important role biogeochemical cycling natural water: (1) by reducing to living organisms (2) favoring leading removal colloid-bound (colloidal pumping). Such highlight one potential application algae remediation metal-contaminated waters. suggest current testing protocols, particular long-term static tests, may underestimate because exudates.