DefinePK

Abstract

Background:  Detection of bacterial species using 16S rRNA is a popular approach in microbiology. This method focuses on 16S rRNA gene which includes both conserved regions shared among bacterial species and variable regions unique to each species. This study aimed for the first time to apply this technique for identifying and classifying the bacterial species which contribute to the formation of anodic biofilm in a tubular photosynthetic microbial desalination cell (PMDC). Methods:  A tubular photosynthesis microbial desalination cell was designed and set up for simultaneous wastewater biotreatment and desalination of seawater associated with clean power generation.16S rRNA sequencing was used for characterization of the dominant microbial strains in the anodic biofilm. The materials involve DNA extracting from bacteria and PCR amplifying for 16S rRNA gene. The kinetic of the bacterial growth in relation to the substrate utilization was studied. Results:  The results revealed the identification of 19 new dominant microbial strains; 13 in the initial shallow biofilm and 6 in the developed biofilm. Results of evaluating the PMDC performance demonstrated that maximum removal efficiency of organic content from sewage was 93±3% associated with power generation of 24.3±2.5 mW/m 3  and 70±4% desalination efficiency of saline water. Results of the kinetic study of biomass growth demonstrated that among the 5 examined models, Monod and Blackman models significantly fitted the experimental data with determination coefficients (R 2 ) of 0.951 and 0.907, respectively. Conclusion:  This study adds to our knowledge of the anode biofilm's involvement in PMDC performance by identifying dominant microbial strains using 16S rRNA sequencing. The findings emphasize microbial contributions to simultaneous treatment of wastewater, desalination of sea water, and electricity generation. This experimental and theoretical investigation paves the way for future breakthroughs in microbial desalination technology, addressing crucial water scarcity issues. Keywords: Photosynthesis microbial desalination cell; Microbial characterization; Biofilm; Bacterial strains; Energy production