Abstract:
Spirulina (Arthrospira) platensis, a blue-green photoautotrophic alga has widely been used for
the production of high valued protein for human and animal feeding as well. The present study
focused on bioaccumulation of Pb2+ and its effects on growth of S. platensis. The species was
cultured in Zarrouk liquid medium with different concentrations of Pb2+ (1, 2, 3, 4 and 5 µg/
mL) and incubated for ten days under optimal conditions. Accumulated amount of Pb2+ in creased with increasing Pb2+ concentrations (1.218, 2.254, 2.673, 3.713 and 5.173 mg/g dry
weight, respectively for 1, 2, 3, 4 and 5 µg/mL of Pb2+, at 2 days of incubation) and decreased as
incubation progressed. Bioconcentration factor (BCF) also reached to the peak (1218, 1127,
888, 928 and 1035 for 1, 2, 3, 4 and 5 µg/mL of Pb2+ respectively) at 2 days of incubation fol lowed by a gradual reduction. No marked differences were found in growth measured as opti cal density at 560 nm. It could therefore be concluded that no remarkable inhibition on
growth of S. platensis is shown when cultured in contaminated water with low concentrations
of Pb2+. Furthermore, the species sounds potential accumulator of Pb2+ and thus could be used
in detoxifying heavy metal affected aquatic ecosystems.
