Perchlorate reduction from a highly concentrated aqueous solution by bacterium Rhodococcus sp. YSPW03

Area of Science:

• Environmental Microbiology
• Bioremediation Technologies

Background:

• Perchlorate contamination poses significant environmental and health risks.
• Developing efficient bioremediation strategies for perchlorate is critical.

Purpose of the Study:

• To investigate the perchlorate reduction capabilities of a novel isolated bacterium, Rhodococcus sp. YSPW03.
• To determine the optimal conditions for perchlorate removal using acetate as an electron donor.

Main Methods:

• Isolation and characterization of Rhodococcus sp. YSPW03.
• Batch and semi-continuous reactor experiments to assess perchlorate reduction rates at varying concentrations.
• Evaluation of acetate concentration and chloride ion inhibition effects.

Main Results:

• Rhodococcus sp. YSPW03 efficiently reduced high perchlorate concentrations (up to 700 mg L(-1)) with acetate.
• Perchlorate reduction rates increased with higher acetate concentrations, achieving complete removal within hours.
• Semi-continuous operation demonstrated sustained efficiency over 140 days, with a peak rate of 280 mg L(-1) day(-1).
• High dissolved chloride ions (1000 mg L(-1)) completely inhibited the process.

Conclusions:

• Rhodococcus sp. YSPW03 is a promising candidate for perchlorate bioremediation.
• Acetate concentration is a key factor in optimizing perchlorate reduction efficiency.
• Chloride ion concentration must be considered for effective bioreactor design and operation.