Work

Effect of Moringa oleifera seeds on the removal of pathogens and pharmaceutical residues in a domestic wastewater treatment plant by an interdisciplinary approach

Year: 2024

Type: article

Abstract: In this transdisciplinary study, we investigated, using genomic tools and physico-chemical parameters, the effect of Moringa oleifera seed (MOS) on the removal of microorganisms and pharmaceutic residues (antibiotics); And also, the development of antibiotic-resistant genes (ARGs) in water samples from a domestic wastewater treatment plant prototype (WWTP). Water samples were analysed with and without addition of powder of Moringa oleifera seed (MOS). The results showed that MOS addition reduced the total bacterial load from 1.73 1010 ± 3.21 109 CFU/L to 6.67 106 ± 5.77 106 CFU/L; While faecal coliforms and E coli were removed with an efficiency of 99% and 57%, respectively. Furthermore, MOS treatment resulted in a reduction in faecal coliforms and E. coli resistant to ampicillin by about 100 % and 96 %, respectively. The results indicated that ciprofloxacin removal efficiency at 29 °C was over 93 % (faecal coliforms) and 68 % (E. coli) with doxycycline. Adding MOS significantly reduced the copy number of the 16S rRNA gene and the genes conferring resistance to β-lactum (blaCTX-M, blaSHV and blaTEM). However, MOS does not reveal a real effectiveness on removal of pollutants (phosphorus and Nnitrates) contrary to what was expected. Additional studies are needed for confirmation from our observations. The findings of this study, whatever the functioning conditions (not optimal) of the prototype followed over 4 years, confirmed that MOS is potentially an effective natural and environmentally friendly coagulant that could be applied to wastewater treatment in low-income countries to remove or minimize multiple pollutants and control ARGs spread. To promote sustainable development, this small-scale study provides guidance for designing infrastructure in resource-limited locations to take advantage of MOS effects in wastewater treatments.

Source: Environmental Science and Pollution Research

DOI: 10.1007/s11356-024-35362-8