Bioremediation of Sr²⁺ ion radionuclide by using marine Streptomyces sp. CuOff24 extracellular polymeric substances

Abstract

BACKGROUND Microbial biosorption is recognized as a resourceful process for the remediation of pollution from contaminated environs. To investigate radionuclide bioremediation, carbohydrate contained extracellular polymeric substance (EPS) and strontium ion (Sr+) tolerant marine actinobacterium has been isolated and identified as Streptomyces sp. CuOff24 through 16S rDNA sequencing. RESULTS EPS was extracted, characterized and the biosorption of the long half‐life radionuclide of Sr2+ was also performed. EPS could remove 82% of Sr2+ from the experimental solution of 100 mg L−1 of strontium chloride (SrCl2). Furthermore, EPS composition also obtained with the presence of Sr2+ radionuclide and major contents of carbohydrate (68.6%) followed by protein (12.3%), nucleic acid (10.4%) and unidentified compounds 8.7%) were quantified. The spectroscopy study also confirmed the presence of carbohydrate functional groups presence in the EPS surface were probably to be involved in Sr2+ adsorption. CONCLUSION Overall results conclude that, marine actinobacterial EPS could be used for the large‐scale remediation of radionuclides contaminated environment. © 2019 Society of Chemical Industry

In Focus: 7th European Bioremediation Conference (EBCVII)

“…investigated radionuclide bioremediation (Sr 2+ ) using extracellular polymeric substances (EPS), which were obtained from a marine actinobacterium, identified as Streptomyces sp. CuOff24 . According to the derived results, such EPS may be suitable for the high level risk management of radioisotopes pollution, offering an eco‐friendly technology with promising results.…”

“…CuOff24. 1 According to the derived results, such EPS may be suitable for the high level risk management of radioisotopes pollution, offering an eco-friendly technology with promising results. In the same trend, Bosco et al studied the bioremediation of soil, artificially contaminated with diesel oil, applying autochthonous microcosm bioaugmentation and biostimulation.…”

Processing of Metals and Metalloids by Actinobacteria: Cell Resistance Mechanisms and Synthesis of Metal(loid)-Based Nanostructures

“…Overall, the high hydrophilicity, chemical reactivity, and stability of polysaccharides make them good biosorbents, as they display several chemical reactive groups [e.g., COO − , CO, NH 3 + , OH − , PO 4 3− , and acetamido (AcNH + )] that can dynamically interact and sequester metal(loid) ions [ 78 , 86 ]. EPS metal(loid) biosorption occurs through electrostatic interactions between the charged biomolecules and metal(loid)s, forming stable metal-EPS complexes [ 27 , 81 , 83 , 87 , 88 ]. The biosorption potential of EPS is correlated with the number of functional groups present within this matrix, enhancing the metal(loid) binding to bacterial cell membranes [ 89 , 90 ].…”

“…Several members of the Actinobacteria phylum were demonstrated to produce EPS in response to metal stress, representing the first defense mechanism against the toxicity of these inorganic compounds ( Table 2 ). Within this phylum, EPS biosynthesis is influenced by the bacterial species, the growth phase, the availability of nutrients, and the selective pressure exerted by toxic compounds [ 84 , 88 ].…”

“…In some Actinobacteria members, EPS-mediated biosorption seemed to be also involved in the detoxification of metal radionuclides, such as strontium (Sr) and cesium (Cs) [ 87 , 88 , 100 ]. Indeed, Nocardiopsis sp.…”