Keragaman dan Potensi Bakteri Pendegradasi Plastik yang Diisolasi dari Sampah Plastik Tempat Pembuangan Akhir (TPA) Terjun Medan Marelan

Abstract

The difficulty of degrading plastic waste in nature causes plastic waste to accumulate and become a problem in the environment, especially in landfill sites. This study aims to determine the diversity and potential of plastic degrading bacteria isolated from Terjun landfill Medan Marelan. Bacteria were isolated from four types of plastic waste namely Low Density Polyethylene (LDPE), Low Linear Density Polyethylene (LLDPE), High Density Polyethylene (HDPE), Polypropylene (PP) from Terjun Medan Marelan landfill. Bacteria were screened for their ability to grow on minimal medium containing 0.5% plastic powder. The ability of bacteria to degrade LDPE and LLDPE on agar media was determined based on plastic weight reduction analysis, Scanning Electron Microscope (SEM) and Fourier Transform Infra Red (FTIR) observations. Isolation results obtained as many as 24 isolates with different morphologies. Total of 5 isolates is L6, LL4, LL6, and H5 were able to grow on media containing plastic powder. The results of molecular identification of known type of bacteria in isolates L6, LL4, and LL6 Bacillus paramycoides, while in isolate H5 Sphingobacterium changzhouense. The ability of five types of bacteria in degrading LDPE and LLDPE sheets, it is known that all bacteria can reduce the weight of plastic sheets in incubation time for 30 days by 8,4% on LDPE and 5,0% on LLDPE. Photomicrograph observation of the degradation test results of LDPE and LLDPE plastic sheets using SEM found the attachment of bacterial colonies and changes in the surface of plastic sheets such as holes and cracks. However, FTIR data did not support any changes or formation of new compounds.