Unlocking 1,3-Propanediol Production by Pseudomonas aeruginosa through Electro-Fermentation

Area of Science:

• Biotechnology
• Biochemical Engineering
• Microbial Electrochemistry

Background:

• 1,3-propanediol (1,3-PDO) is a key industrial chemical and polymer precursor.
• Glycerol, a biodiesel byproduct, is a sustainable feedstock for 1,3-PDO production.
• Traditional fermentation methods for 1,3-PDO have limitations in yield and efficiency.

Purpose of the Study:

• To investigate the efficacy of electro-fermentation for 1,3-propanediol (1,3-PDO) production using Pseudomonas aeruginosa.
• To compare 1,3-PDO production via electro-fermentation versus traditional fermentation.
• To explore the impact of applied voltage on 1,3-PDO biosynthesis and metabolic pathways.

Main Methods:

• Utilized a single-chamber microbial electrochemical cell with carbon cloth and platinum electrodes.
• Conducted electro-fermentation assays under varying applied voltages (0.01–0.4 V) and potentiostatic control.
• Employed Pseudomonas aeruginosa for glycerol bioconversion to 1,3-PDO.
• Analyzed 1,3-PDO concentration, yield, productivity, and electron recovery.

Main Results:

• Electro-fermentation significantly enhanced 1,3-PDO production compared to traditional fermentation.
• The optimal voltage of 0.05 V resulted in a 1,3-PDO concentration of 99.49 ± 0.57 mmol L⁻¹, a yield of 0.78 ± 0.01 mol/mol, and productivity of 15.70 ± 0.25 mmol L⁻¹ h⁻¹.
• Electron recovery was substantially higher in electro-fermentation (89.65 ± 0.37%) compared to traditional fermentation (45.14 ± 0.89%), indicating a more efficient reductive pathway.

Conclusions:

• Electro-fermentation effectively modulates Pseudomonas aeruginosa metabolism for enhanced 1,3-PDO production.
• This bioelectrochemical approach offers a promising, sustainable alternative for producing 1,3-PDO from glycerol.
• The findings support the integration of electro-fermentation into biorefineries for value-added chemical synthesis.