Potential bacteria capable of remediating mercury contaminated soils

Abstract

Mercury content in ex-artisanal and small-scale gold mining areas in Cianjur District, Province of West Java, Indonesia was 7 to 36 mg L−1. It has exceeded the threshold value for industrial land. Bioremediation of mercury using mercury-resistant bacteria is attractive to remove mercury from the environment because it is more effective and less expensive. The objective of this study was to obtain potential bacteria capable of accumulating mercury to be used to remediate mercury contaminated soils in ex-gold mining areas. Potential bacteria isolates were characterized for their phenotypic and biochemical properties using the Biolog system. Thirty-two mercury-resistant bacteria were successfully isolated from the rhizosphere of Pityrogramma tartarea growing predominantly around tailings of ex-artisanal gold mining. After screening the presence of mercury, the three best isolates showing high resistances are Pseudomonas putida R2.13 and P. maculicola R4.27 that are capable to tolerate 180 mg L−1 mercury, and Enterobacter aerogenes R3.24 that is capable to survive at 170 mg L−1. Furthermore, the three bacteria also can fix atmospheric nitrogen and solubilize phosphate, but they cannot solubilize potassium. These indicate that P. maculicola R4.27, P. putida R2.13, and E. aerogenes R3.24 are potential as bioaccumulation agents on mercury-contaminated soils.

Isolation and characterization of mercury-resistant microbes from gold mine area in Mount Pongkor, Bogor District, Indonesia

“…In the other region of Indonesia, Febria et al (2016) have isolated bacteria with the highest resistance mercury level from Sijunjung District; West Sumatra was only 250 ppm. Meanwhile, Ginting et al (2021) have reported the highest resistance mercury level up to 170 ppm around ex-gold mine tailings. The mercuryresistant fungus from contaminated agricultural soil in Buru Island had been reported to grow well at 25 ppm (Hindersah et al 2018a).…”

Screening and profiling of mercury-resistant Azotobacter isolated from gold mine tailing in Pongkor, West Java

“…Researchers reported the presence of Hg-resistant bacteria from various Hg-contaminated areas. Hg-resistant bacteria from tailing contaminated with up to 3,000 mg/kg Hg in Pongkor, West Java (Irawati et al, 2012), 250 mg/kg Hg in Sijunjung District, West Sumatra (Febria et al, 2016) and 36 mg/kg Hg in soil (Ginting et al, 2021). Nonetheless, several studies verified that grampositive bacteria were predominant in Hgcontaminated tailing (Chasanah et al, 2018;Naguib et al, 2018;Niane et al, 2019), and Azotobacter bd3a was able to grow on media containing 20 mg/L of HgCl2 (Hindersah et al, 2017).…”

Unraveling Techniques for Plant Microbiome Structure Analysis

“…Differences in these forms of utilizations could be analyzed and showed the different in the viable microorganisms and eventually microbial population. Many manual and commercial systems identify and characterize the microbe community with these methods [35][36][37].…”