Performance of Moringa oleifera seeds protein and Moringa oleifera seeds protein-polyaluminum chloride composite coagulant in removing organic matter and antibiotic resistant bacteria from hospital wastewater

Abstract

The aims of this study were focused on the preparation of the Moringa oleifera seeds protein-polyaluminum chloride composite coagulant that improves the coagulation process of organic matters and pathogenic bacteria. The performance of M. oleifera seeds protein (MOP) and the composite coagulant (MOP-PACl) was investigated using synthetic water and hospital wastewater. Electrophoresis SDS-PAGE, Fourier Transform Infrared (FTIR) spectroscopy and Scanning Electron Microscopy (SEM) were performed to characterize MOP. Electrophoresis analysis showed that MOP was a dimeric protein with mean molecular weight of 37.5 kDa. Jar-test results revealed that 64 % of turbidity, 38.36 % of COD, 16.54 % UV254, 74.28 % against E. coli, 76.36 % against V. cholerae and 90 % against P. aeruginosa strains were removed from hospital wastewater using MOP at dose of 320 mg/L. Composite coagulant MOP-PACl significantly improved the quality of treated water with removal efficiency of 86.11 % turbidity, 60.12 % COD, 58.82 % UV254, 79.11 % against E. coli, 98.66 % against V. cholerae and 100 % against P. aeruginosa strains with Al:MOP ratio of 0.54 and aluminum dosage in MOP-PACl coagulant of 4.32 mg/L. In addition, the antimicrobial investigation performed with MOP showed inhibition zone of 15 mm against E. coli strain and 16 mm against P. aeruginosa strain whereas 20 mm against P. aeruginosa and 16 mm against E. coli were obtained using MOP-PACl at Al:MOP ratio of 0.27. The results highlighted that MOP and MOP-PACl composite coagulant could be successfully used as coagulant for removing the pollutants from hospital wastewater.