Biosorption and Sequestration of Lead by Stutzerimonas Stutzeri Strain Isolated from Industrial Effluent

Abstract

Background: This study was carried out to isolate and characterize the bacterial strains from industrial effluent for their biosorption and sequestration potential.

 Methods: In this study we have done with the enrichment of the cultures for the isolation of bacterial strains, in which the tryptone soya broth (TSB) and mineral salt medium (MSM) supplemented with different concentrations of lead metal. Further, screening was done on the basis of tolerance where turbidity act as an indicator which corelates with the tolerance towards varying concentrations of lead. Selected isolates were studied for their growth kinetics and mass balance profiling studies. AS-3 strain showed the best sorption and sequestration potential that was further subjected to biochemical and molecular characterization including 16S rDNA sequencing was performed and analysis was done. Phylogenetic tree was generated for maximum likelihood using MEGA11 software. One isolate from this study was finally characterized as Stutzerimonas Stutzeri.

 Results: Out of the 10 isolates, AS-3 exhibited 99% of the sequestration for the metal (a.i.  50 mg/l Pb) among other isolates which accumulated variable amounts of Pb. After attaining the required growth in shake flasks, mass balance studies further confirmed the maximum sequestration. Characterization of AS-3 revealed its phylogenetic relationship with the family Pseudomonadaceae (ɤ-Proteobacteria) and 99% similarity with Stutzerimonas sp., a facultative anaerobe.