Exploring Microbial Community from the Gulf of Thailand Sediment for Plastic Degradation

Plastic waste poses a significant threat to the environment and living
organisms. Improper waste management leads to the spreading of postconsumer
plastic throughout the world's oceans. These plastic wastes take an
extremely long time to decompose in nature. An interesting way to treat plastic
waste is using microorganisms to degrade plastic. The Gulf of Thailand, which
has been contaminated with plastic waste, was used to isolate the plasticdegrading
microbes. Therefore, this study aims to investigate the
microorganisms involved in the degradation of plastic. Sediment from a
plastic contaminated site from the Gulf of Thailand, was enriched in MSM
media containing normal or oxidized polypropylene (PP) sheets as a sole
carbon source to promote the growth of plastic-degrading microbe. After 2
months of incubation, the biofilm colonizations on the plastic surface and the
Gulf of Thailand sediment were analyzed by 16S rRNA sequencing to
investigate the diversity of the microbial community. The results revealed that
the diversity of the microbial community in enrichment culture decreased
significantly, compared with the sediment from the Gulf of Thailand. Whereas
some microbial species increased in the enrichment culture with normal and
oxidized PP. The dominant genera in sediment incubated with normal PP were
Brevibacillus, Methyloceanibacter, and Micromonospora. Genera Micromonospora, Ammoniphilus, and Brevibacillus were predominant in enrichment culture with oxidized PP.