Competitive biosorption of different forms of lead [Pb(NO₃)₂ and Pb(CH₃COO)₂] on growth, biomass and proline in <i>Spirulina platensis</i> (Cyanophyta)

Abstract

Spirulina platensis growth parameters [chlorophyll a (chl a) and dry-wet weight] effects on proline content, lead accumulation and the combined effect of the different forms of lead [Pb (NO₃)₂, Pb (CH₃COO)₂] and pH (6 to 8) were investigated for 192 h. The accumulation and form of lead were determined to be effective on growth parameters. While the highest chl a value (562.37 μgl^-1) and lead accumulation (58.74 μgg^-1) were found in medium with 30 mgl^-1 Pb (CH₃COO)₂ and pH 6, the highest proline content was found in 30 mgl^-1 Pb (NO₃)₂ and pH 6. This study depict an inverse relationship between lead accumulation in the test algae and low pH which suggests that proline might be produced at the expense of the material(s) required for the development of S. platensis.

Key words: Spirulina, heavy metal, growth parameters, uptake.