Mercury absorption by Pseudomonas fluorescens BM07 grown at two different temperatures

Area of Science:

• Environmental Microbiology
• Bioremediation
• Biomaterials

Background:

• Pseudomonas fluorescens BM07 produces a cold-induced biopolymer at temperatures as low as 10°C.
• Biopolymer synthesis is inhibited at 30°C.
• Investigating mercury (Hg2+) ion biosorption by BM07 cells grown at different temperatures.

Purpose of the Study:

• To evaluate the biosorption capacity of P. fluorescens BM07 for mercury ions.
• To determine the influence of growth temperature (10°C vs. 30°C) on mercury biosorption.
• To optimize biosorption conditions, including pH, contact time, metal concentration, and biomass dose.

Main Methods:

• Culturing P. fluorescens BM07 at 10°C and 30°C.
• Assessing mercury biosorption under varying pH, contact time, initial Hg2+ concentration, and biomass concentration.
• Analyzing equilibrium data using the Langmuir adsorption model.

Main Results:

• Optimal mercury biosorption occurred at pH 7.0.
• BM07 cells grown at 10°C exhibited higher mercury uptake (102 mg/g) compared to those grown at 30°C (60 mg/g).
• Maximum removal efficiency was achieved at a cell biomass concentration of 0.83 mg dry biomass/ml.
• Langmuir model indicated higher maximum adsorption capacity (qmax) for 10°C grown cells (82.25 mg/g) versus 30°C grown cells (62.9 mg/g).

Conclusions:

• The cold-induced biopolymer produced by P. fluorescens BM07 at 10°C significantly enhances mercury biosorption efficiency.
• Temperature plays a critical role in the production of biosorptive biopolymers.
• P. fluorescens BM07 is a promising candidate for mercury bioremediation applications.