Treatment of Wastewater using Bioflocculant Produced by Serratia marcesens and Pseudomonas aeruginosa

IJEP 42(9): 1141-1145 : Vol. 42 Issue. 9 (September 2022)

Zinah M. Mahdi*, Manar A. Ehmud and Duaa S. Khazaal

Ministry of Science and Technology, Water and Environment Directory, Iraq


Two local bacterial isolates were used in the production of bioflocculants that help in reducing some pollutants from wastewater. Pseudomonas aeruginosa and Serratia marcesens were isolated from Rustumiya wastewater treatment plant in Baghdad, Iraq. Kurane method is used in bioflocculate production and Kaolin clay test is applied for flocculation efficiency. The optimum output of bio-flocculant was obtained after an incubation period of 30°C for 48 hr, pH 7 and with an inoculum volume of 2 mL with three concentrations (100, 200 and 300 mg/L). Flocculation efficiency of 86.5%, 87.3% and 94. 5% was seen by S. marcesens, P. aeruginosa and alum, respectively. The maximum activity of reduction process was observed with chemical oxygen demand, biological oxygen demand and turbidity with P. aeruginosa (95%, 64.2%, 68.7%) and S. marcesens (65.2%, 70%, 82.7%), consecutively. P. aeruginosa showed slight but evident reduction efficiency in BOD and COD.


Bioflocculation, Bioflocculant crude, Wastewater, S. marcesens, Turbidity


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