Global Hotspots and Trends in Microbial Plastic Biodegradation for Plastic Waste Management: A Mini-Review and Bibliometric Analysis

The accumulation and persistence of plastic waste have made microbial plastic biodegradation an important topic in pollution control, environmental remediation, and sustainable materials management. This study combines a mini-review with bibliometric analysis to link mechanistic understanding with global research trends in microbial plastic biodegradation from 2000 to 2025. The mini-review summarizes polymer weathering and fragmentation, microbial colonization and biofilm formation, extracellular depolymerization or oxidative chain cleavage, uptake and intracellular catabolism of plastic-derived intermediates, physiological regulation, ecological interactions, and potential applications in bioremediation and upcycling. Bibliographic records were retrieved from the Web of Science Core Collection and analyzed using bibliometrix, VOSviewer, CiteSpace, and SCImago Graphica. A total of 2959 publications were identified. Publication output increased markedly, especially after 2018, reaching 617 publications in 2025; cumulative citations reached 31,373. China, India, and the United States were the leading contributors. Journal and keyword analyses showed strong links among environmental science, polymer science, microbiology, biotechnology, and engineering. Highly cited publications mainly focused on plastic biodegradability, biodegradable polymers, engineered PET depolymerization, polyethylene degradation, and microbial or enzymatic degradation mechanisms. Keyword evolution revealed a shift from material-oriented topics, including polymer blends, poly(vinyl alcohol), polyesters, morphology, mechanical properties, composites, and polyhydroxyalkanoates, toward degrading enzymes, cutinase-like enzymes, plastic-degrading strains, microbial colonization, fungi, and marine environmental degradation. Overall, microbial plastic biodegradation has evolved from material-centered biodegradability evaluation toward a mechanism-oriented and environment-oriented interdisciplinary field.