Molecular Characterization of Polyethylene Degrading Bacteria and Fungi from a Refuse Dump in Port Harcourt, Rivers State Nigeria

Abstract

This study was aimed at identifying and characterizing Polyethylene degrading bacterial isolates from a refuse dump in Amadi-Ama Port Harcourt Rivers State Nigeria. The microorganisms were isolated from plastic polyethylene wastes deposited in the soil of a refuse dump in Amadi-Ama, Port Harcourt, Rivers State. Molecular studies were done to identify and characterize the bacteria and fungi involved in the degradation of the polyethylene. The identified Ethylene utilizing bacteria species include Bacillus sp., Micrococcus sp. and Pseudomonas sp. while the fungal species include Alternaria sp. and Fusarium sp. The obtained 16s rRNA and Internal Transcribed Spacer (ITS) sequence from the isolate produced an exact match during the megablast search for highly similar sequences from the National Center for Biotechnology Information (NCBI) non-redundant nucleotide (nr/nt) database.  The 16S rRNA and Internal Transcribed Spacer (ITS) of the isolates showed a percentage similarity to other species at 100%.  The evolutionary distances computed using the Jukes-Cantor method were in agreement with the phylogenetic placement of the 16S rRNA and Internal Transcribed Spacer (ITS) of the isolates within the Bacillus and Lysinibacillus sp and revealed a closely relatedness to Bacillus safensis and Lysinibacillus sphaericus as well as within the Aspergillus and Fusarium sp and revealed a closely relatedness to Aspergillus   flavipes and Fusariun ketaroplasticum. Bacteria and fungi species degraded the polyethylene from the refuse dump in in Amadi-Ama Portharcourt Rivers State Nigeria. The bacterial species identified to be involved in the degradation of polyethylene from the refuse dump were Bacillus sp., Micrococcus sp. and Pseudomonas sp. with Bacillus safensis and Lysinibacillus sphaericus being the bacterial organisms found to be present while the fungal species were Alternaria sp. and Fusarium sp. with Aspergillus flavipes and Fusariun ketaroplasticum being the fungal organisms found to be present.