Two cyanobacterial species Nostoc calcicola
HH-12 and Chroococcus minutus
from a textile mill oxidation pond were examined individually and as consortium for their chromium(VI) tolerance
and bioremoval from aqueous solutions. Both species were tolerant to the metal and showed significant increase
(p<0.01) in concentration of chlorophyll and carotenoids at higher concentration of chromium, and the tolerance
further in the consortium. Concentration of phycobilins also increased in the pure culture of Chroococcus
consortium was also higher in response to increasing chromium concentration in the medium. Chromium
bioremoval potential was high in both species and the consortium was even more efficient in metal removal.
Probable antioxidative role of carotenoids in metal tolerance have also been discussed.