Exploration of the polypropylene degrading bacteria candidates from the passive zone of the Supit Urang landfill in Malang city by using the next generation sequencing (NGS) method

The buildup of plastic waste in the passive zone of the Supit Urang landfill located in Malang City has been ongoing since 2018. Currently, plastic waste in this area appears brittle and cracked, potentially providing a habitat for polypropylene (PP)-degrading bacteria. This research aims to explore the potential of PP-degrading bacteria using Next Generation Sequencing (NGS) techniques in the passive zone of the Supit Urang landfill, Malang City. Our study was conducted in four steps: 1) sampling and sample collection, 2) DNA sequencing, 3) bioinformatics analysis, and 4) bibliometric analysis for identification of PP-degrading bacteria. Based on the results of full-length sequencing using Oxford Nanopore Technologies with whole amplicon sequencing techniques, a total of 2,496 sequences were read, and 1,713 sequences were identified as species in the passive zone of the Supit Urang landfill. The most abundant bacterial phyla in this region were Proteobacteria (51%), Firmicutes (21%), Acidobacteria (7%), Bacteroidetes (6%), Planctomycetes (4%), Actinobacteria (3%), Gemmatimonadetes (2%), Nitrospirae (2%), and Chloroflexi (2%). These results indicate that Proteobacteria and Firmicutes are abundant in the passive zone of TPA Supit Urang and could potentially biodegrade microplastics such as polypropylene. The narrative review's research showed that numerous bacterial species, including Bacillus thuringiensis, B. cereus, and Bacillus sp., were identified by NGS analysis as possible PP-degrading bacteria.