title: Accumulation of lead by free and immobilized cyanobacteria with special reference to accumulation factor and recovery.
abstract: Lead accumulation by free and immobilized cyanobacteria, Lyngbya majuscula and Spirulina subsalsa was studied. Exponentially growing biomass was exposed to 1-20mg L(-1) of Pb(II) solution at pH 6, 7 and 8 for time periods ranging from 10 min to 48 h. L. majuscula accumulated 10 times more Pb (13.5 mg g(-1)) than S. subsalsa (1.32 mg g(-1)) at pH 6 within 3h of exposure to 20mg L(-1) Pb(II) solution and 76% of the Pb could be recovered using 0.1M EDTA. This chelator (2 μM) did not influence Pb accumulation whereas 100 μM citrate increased that of S. subsalsa 6- to 8-fold. L. majuscula filaments enmeshed in a glass wool packed in a column removed 95.8% of the Pb from a 5mg L(-1) Pb solution compared to free and dead biomass which removed 64 and 33.6% Pb respectively. A 92.5% recovery of accumulated Pb from the immobilized biomass suggests that repeated absorption-desorption is possible.
authors.affiliation: Phycology Laboratory, Department of Botany, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700019, India.
authors.forename: Nabanita
authors.initials: N
authors.lastname: Chakraborty
authors.forename: Amita
authors.initials: A
authors.lastname: Banerjee
authors.forename: Ruma
authors.initials: R
authors.lastname: Pal
mesh_terms: D000042:Absorption; D018533:Biomass; D002614:Chelating Agents / Q000737:chemistry*; D019343:Citric Acid / Q000737:chemistry; D000458:Cyanobacteria / Q000378:metabolism*; D004492:Edetic Acid / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007194:India; D007854:Lead / Q000493:pharmacokinetics*; D013045:Species Specificity; D013054:Spectrophotometry, Atomic; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
chemical_list: D002614:Chelating Agents; D014874:Water Pollutants, Chemical; D019343:Citric Acid; D007854:Lead; D004492:Edetic Acid