A new approach using bioflocculants and nanotechnology to treat wastewater combines the cost-effective and ecologically sustainable means of treating wastewater with the original flocculating properties of the bioflocculants by using nanoparticles (silver nanoparticles) synthesized by different bacterial species like Bacillus spp. (KWN4, RWN2, etc.). There are various steps associated with the formation of nanobioflocculants. Some examples of such microorganisms to be used to form nanoparticles for the bioflocculation process include F. oxysporum, Verticillium spp, Yeast strain MKY3, Candida glabrata, Pseudomonas stutzeri, Lactobacillus strains, Escherichia coli, and Klebsiella pneumonia. Coagulants and flocculants used in wastewater treatment are divalent +ve and −ve charged chemical compounds that utilize iron salts (FeCl3 or Fe(SO4)3), aluminum salts(Al2(SO4)3), hydrated limes, magnesium carbonate and polymers (polyaluminum chloride (PAC), aluminum chlorohydrate, polyaluminum sulfate chloride, and polyferric sulfate), polyethyleneimine(organic synthetic polymeric flocculants), chitosan and sodium alginate (natural flocculants), and nanoparticles like Au, Ag, CdS, and magnetite. The biological adaptation of microbes to their surroundings is aided by mechanisms like redox reactions that alter metal concentration. Additionally, bacteria are helped to live in environments with high metal concentrations by outflow, intracellular accumulation, precipitation of metals, and extracellular complex formation. Nano-bioflocculants have been used for the treatment/removal of nutrients, COD, BOD, reduction, and turbidity. Fourier transform infrared spectroscopy (FTIR) is used to identify the carboxyl, hydroxyl, and amino groups. A scanning electron microscope (SEM) is used to evaluate the bioflocculant structures with a netted texture. A bioluminescent bacterium like Aliivibrio fischen is used in the Microtox Assay technique to detect or determine the toxicity of a particular substance or substrate.
