Isolation and Characterization of a High-Efficiency Bioflocculant-Producing Strain of Pseudomonas fluorescens

This study aimed to thoroughly explore, optimize, and characterize a Bioflocculant produced by a novel Pseudomonas fluorescens PF-1 strain isolated from active sewage sludge. When examined under refined culture conditions, including an incubation temperature of 36°C, a neutral pH of 7, and the use of sucrose and yeast extract as the most effective carbon and nitrogen sources, respectively, this strain exhibited promising flocculating capabilities. An inoculum volume of 5% (v/v) further amplified Bioflocculant manufacturing. Under these conditions, the strain demonstrated remarkably high flocculating activity, reaching 87.4%. Biochemical composition analysis revealed that the extracted Bioflocculant principally comprised carbohydrates at 76.3% and proteins at 17.2%, indicating a polysaccharide-protein complex nature. FTIR spectroscopy supported the existence of functional groups, including carboxyl, hydroxyl, and amide, crucial for flocculation mechanisms. SEM imaging depicted a dense, interwoven fibril matrix perfectly suited for trapping and aggregating suspended particles. The Bioflocculant also manifested high thermal resilience up to 80°C and retained activity across a wide pH range from 4 to 8. Wastewater treatment tests employing genuine effluents showed outstanding pollutant removal proficiencies, with reductions in chemical oxygen demand (COD) and biological oxygen demand (BOD) achieving an impressive 90.2% and 88.6% respectively. These conclusions demonstrate strong potential as a Bioflocculant created by P. fluorescens PF-1 as an eco-friendly and highly effective replacement for conventional chemical flocculants in wastewater treatment applications.