Arthrospira (Spirulina) species as bioadsorbents for lead, chromium, and cadmium - a comparative study

Abstract

Arthrospira (Spirulina) belongs to the cyanobacterial family has been reported as a potential bioremediation agent. The bioadsorption potential of Arthrospira species, namely A. indica, A. maxima, and A. platensis, was tested against lead, chromium, and cadmium toxicity under laboratory conditions. Arthrospira species were cultured in Zarrouk's medium containing lead, chromium, and cadmium with two varying concentrations (0.01 and 0.05mM) and in river water contaminated with tannery effluent containing these heavy metals. Parameters like specific growth rate, total chlorophyll, and total protein contents were analyzed and compared. Specific growth rate, total chlorophyll, and total protein contents possess dose dependent decrease with increase in concentrations of metals and also in heavy metal contaminated tannery effluent when compared with control. Statistical analysis revealed that there is a good correlation between the specific growth rate and protein content in all the species. Atomic absorption spectrometry analysis also revealed that there is a maximum bioadsorption potential of the Arthrospira species. Results indicated that the three Arthrospira species used in this experiment were found to be potential candidates for bioadsorption against lead, chromium, and cadmium. Arthrospira species (A. indica, A. maxima, A. platensis) were used to study heavy metals adsorption from tannery effluents. The adsorption capacity was analysed by growth estimation, chlorophyll content, protein content. The results show that the Arthrospira species possess high adsorption capacity toward lead, chromium, cadmium.