Biodegradation of polypropylene plastics in vitro and natural condition by Streptomyces sp. isolated from plastic-contaminated sites

Most plastic degradation studies are conducted under controlled laboratory conditions. The current study investigated the ability to degrade Polypropylene (PP) plastic by Streptomyces ardesiacus strain NBI0111 under both laboratory and natural conditions. This strain exhibited the ability to degrade PP when cultured in BH medium and using PP plastics as carbon sources. After a 90-day incubation period, the weight loss of PP plastics reached 17.52% (p < 0.05). The surface of the PP plastic showed significant changes compared to the control group. Chemical changes in the plastic were also detected on the 60th and 90th days, as confirmed by FTIR and GC-MS analyses. This strain was applied to degrade PP plastic in soils under natural conditions. Strain NBI0111 also resulted in a notable weight loss. The biodegradation test group exhibited a significant 12.5% decrease compared to only a 3.88% decrease in the control group (p < 0.05). Furthermore, a strong positive correlation between the weight loss of PP plastic cups and the density of microbial populations was observed. The capabilities demonstrated by Streptomyces ardesiacus strain NBI0111 in this study hold great promise for on-site plastic remediation, offering a sustainable solution to the problem of plastic pollution in the future.