Phenol biodegradation by isolated Citrobacter strain under hypersaline conditions

Area of Science:

• Environmental Microbiology
• Bioremediation
• Industrial Biotechnology

Background:

• Phenolic compounds are toxic pollutants found in hypersaline industrial effluents.
• Effective treatment of these effluents is crucial before discharge into water bodies.
• Halophilic microorganisms offer potential solutions for bioremediation in high-salinity environments.

Purpose of the Study:

• To isolate and identify a halophilic microorganism capable of degrading phenol.
• To evaluate the biodegradation efficiency of the isolated strain under varying conditions.
• To assess the potential of this strain for treating hypersaline phenolic wastewater.

Main Methods:

• Isolation and identification of a halophilic strain using 16S rRNA gene sequencing.
• Cultivation and assessment of phenol biodegradation and cell growth.
• Optimization studies for initial phenol concentration, salinity, temperature, and pH.

Main Results:

• A halophilic Citrobacter strain was isolated, utilizing phenol as its sole carbon and energy source.
• The strain demonstrated high tolerance to phenol (up to 1,100 mg L⁻¹) and salinity (0-10% NaCl).
• Optimal conditions for phenol removal were 400 mg L⁻¹ initial concentration, 35 °C, pH 6.0, and 0% salinity, achieving complete degradation within 20 hours.

Conclusions:

• The isolated Citrobacter strain exhibits significant potential for the bioremediation of phenol in hypersaline industrial wastewaters.
• Its ability to thrive in high-salinity and high-phenol conditions makes it a valuable candidate for wastewater treatment.
• This research provides a viable biological approach for managing challenging phenolic effluents.