Examining and identifying bacteria-mediated polyethylene terephthalate bottle waste degradation Byprops

Plastic waste accumulation raises concerns about global environmental risk due to persistence of Polyethylene terephthalate (PET) which degrades slowly and release harmful compounds. Hence, it becomes increasingly imperative to remove plastic waste from the environment. In light of this, the present study examined the PET degradation capacity of naturally existing bacteria obtained from sites where plastic garbage was dumped. Bacillus subtilis was isolated from the old PET plastic waste bottles. Pre-treated PET (Ultraviolet light, Sunlight and untreated PET) plastics were cultured with Bacillus subtilis for six months at 37o C to examine their biodegradability in Minimal Salt Medium. The functional groups of PET wastes and deteriorated by-products in MSM were analyzed for change using Gas chromatography–mass spectrometry (GC-MS) and Fourier–transform infrared spectroscopy (FTIR). It revealed that the bacterial biodegradation led to appearance of new peaks such as alkyl aryl ether and alkene groups in ultraviolet-pretreated PET microplastics when compared to sunlight and control PET microplastics. After six months of incubation of PET microplastics, Bis(2-ethylhexyl) phthalate, fatty acids, amides, and ketones were detected in the supernatants of Ultraviolet-treated and sunlight-treated PET microplastics in minimal salt medium. The soil bacteria showed the potential to degrade PET and hence could be employed for eliminating PET from plastic contaminated sites.