Fungal-Assisted Biodegradation of Bioplastics: A Comparative Analytical Study

The growing environmental concerns associated with conventional plastics have accelerated research on biodegradable alternatives. The accumulation of plastic waste in landfills and natural ecosystems has intensified issues such as soil contamination, marine pollution, and ecological imbalance. In response to these challenges, degradable plastics have emerged as potential alternatives due to their enhanced susceptibility to microbial degradation. The present study evaluates the fungal-mediated degradation of degradable polyethylene (PE) plastic, a modified polyolefin polymer designed to undergo accelerated environmental breakdown. Fungal strains, including Fusarium spp. and Aspergillus niger, were isolated and identified using conventional lactophenol cotton blue staining techniques. Qualitative biodegradation analysis was performed following the Modified ASTM G21-70 protocol. Quantitative degradation was assessed by determining percentage weight loss using three different methods: modified ASTM, broth culture method, and soil burial test. The experiments were conducted under controlled laboratory conditions at 28 ± 2 °C for an incubation period of 30 days. The highest degradation was observed in the Modified ASTM method, with A. niger showing 44% weight loss and Fusarium spp. 33%. In the broth culture method, degradation percentages were 31.5% for A. niger and 26.3% for Fusarium species, while the soil burial test exhibited comparatively lower degradation rates of 15.7% and 10.5%, respectively. Statistical analysis indicated significant differences in degradation efficiency among the tested methods (p < 0.05). Structural alterations in the degraded polyethylene samples were further characterized using Fourier Transform Infrared Spectroscopy (FTIR), which confirmed changes in functional groups indicative of polymer breakdown. These findings demonstrate the effective role of fungal cultures in enhancing the degradation of degradable polyethylene and suggest that such microbial approaches could be further explored as an eco-friendly strategy for reducing plastic waste accumulation and supporting sustainable plastic waste management.