Survivability of Polyethylene Degrading Microbes in the Presence of Titania Nanoparticles

Survivability of Polyethylene Degrading Microbes in the Presence of Titania Nanoparticles

The bacterial degradation of Polyethylene, not unlike the other plastic materials, is generally very slow. The presence of titania (TiO2) nanoparticles (TNPs) faster photocatalytic degradation of polyethylene can take place which can help in accelerating the bacterial degradation; in the presence of TNPs, polyethylene is initially photo catalytically degraded to smaller pieces which allows the bacteria initially degrade polyethylene to smaller size that allow the TNPs to act more effectively. But, TNPs also have a germicidal effect and it is important to find out the safe concentration of TNPs with minimal toxicity and good photocatalytic activity. For identification of the polyethylene degrading microbial strains from the soil, from samples collected from the local plastic dumpsite, were subjected to gram staining, biochemical tests and 16s rRNA gene sequencing, and then tested for polyethylene degradation under different TNP concentrations. In this work it has been established, through Optical Density (OD), Colony counting (CFU measurement), Scanning Electron Microscopy (SEM) and measurement of the Carbonyl Index (CI) using FTIR, that up to a concentration of 1%, the TNPs have a positive effect on polymer degradation. Results show that biodegradation of polyethylene in the presence of TNPs was much stronger than the degradation by TNPs alone or biodegradation in the absence of TNPs. The results could play an important role in the development of environment friendly shopping bags and other polyethylene based products.