Cyanobacteria as test organisms and biosorbents

Abstract

Bioassay and biosorption potentials of different groups of cyanobacteria (CB)—Nostoc linckia (Roth.) Born. et Flah. No. 271, natural biofilms dominated by CB of Phormidium genus, and biofilms dominated by Nostoc commune (Vauch. Elenk)—were estimated. The physiological-biochemical response of CB to the influence of copper sulfate (II) (catalase activity with a gasometric method and dehydrogenase activity, lipid peroxidation, and chlorophyll ɑ and pheophytin contents with a spectrophotometric method) was studied; metal bioaccumulation was determined with a stripping voltammetry method. It was found that the communities dominated by Phormidium genus (CB biomass 0.2 g/dm³) removed copper compounds from the solutions with Cu²⁺ ion concentration of 20 mg/dm³ almost completely (by 99%); communities dominated by CB N. commune, by 87%; and pure culture of N. linckia, by 50%. Dehydrogenase and catalase activities and the intensity of bioluminescence proved to be sensitive indicators of the response of CB to Cu²⁺ ions. The impact of Cu²⁺ ions (20 mg/dm³) on a biofilm dominated by CB of Phormidium genus resulted in the fivefold decrease of catalase activity during 24 h; dehydrogenase activity decreased by nearly 357 times. The bioluminescence intensity during 24 h decreased by 1.3–100 times under the impact of Cu²⁺ (2 mg/dm³) and by 8.6–200 times in variants with a higher concentration of Cu²⁺ (20 mg/dm³). This regularity can be used as a test function in bioassay.