Okonkwo NN¹*, Egurefa SO², Okey-Ndeche NF³, Awari VG⁴, Ogbunude AP⁵, Akpadolu KC¹, Ogujiofor FI¹, Ikegwuonu EA¹, Ojeah IK⁶ and Agu KC¹

¹Applied Microbiology Department, Nnamdi Azikiwe University, Awka, Nigeria
²Department of Science Laboratory Technology, Southern Delta University, Ozoro, Delta State, Nigeria
³Department of Microbiology, Faculty of Natural Sciences, Veritas University Abuja, Area Council, Bwari, Federal Capital Territory, Nigeria
⁴Depertment of Microbiology, Tansian University, Umunya, Anambra, Nigeria
⁵Department of Public Health, School of Health and Life Sciences, Teeside University, Middlesbrough, UK
⁶Department of Microbiology, Faculty of Science, University of Delta Agbor, Delta State, Nigeria

*Corresponding Author: Okonkwo NN, Applied Microbiology Department, Nnamdi Azikiwe University, Awka, Nigeria.

Received: May 19, 2026; Published: June 15, 2026

Abstract

Styrofoam, a highly persistent plastic polymer composed primarily of polystyrene, poses a significant global environmental threat due to its recalcitrance to natural degradation and the hazardous byproducts released during conventional disposal. This study explored an eco-friendly alternative by investigating the biodegradation potential of fungal strains isolated from a 30-day vermicompost. The primary goal was to assess the feasibility and efficiency of utilizing both wild-type and genetically modified molds specifically Aspergillus niger and Penicillium chrysogenum to degrade Styrofoam. Fungal strains were isolated from vermicompost collected in Awka, Nigeria, and identified through morphological and microscopic analysis. Genetic modification was performed via UV mutagenesis for 7 consecutive days. Both wild-type and mutant strains were inoculated into Styrofoam Mineral Salt Vitamins Medium (MSVM) broth containing 5% Styrofoam and incubated in a rotary shaker at 150 rpm for 25 days. Degradation kinetics were monitored at 5-day intervals using spectrophotometric analysis at 680 nm to measure changes in optical density (OD). Penicillium chrysogenum and Aspergillus niger were successfully isolated and identified. Spectrophotometric data revealed that the genetically modified strain of P. chrysogenum exhibited an accelerated degradation process, surpassing the wild-type strain by Day 5 and maintaining higher optical density values throughout the 20-day monitoring period. Conversely, the mutant strain of A. niger showed lower degradative potential compared to its wild-type counterpart. The wild-type A. niger demonstrated steady degradative efficacy, reaching an OD of 1.247 by Day 20. The findings suggest that indigenous fungi from vermicompost possess the ability to deteriorate Styrofoam, and UV-induced mutation can successfully enhance the degradation efficiency of specific strains like Penicillium chrysogenum. These results highlight the potential of using genetically improved microbial agents as a sustainable strategy for managing expanded polystyrene waste.

Keywords: Biodegradation; Styrofoam; UV Mutagenesis; Aspergillus niger; Penicillium chrysogenum; Vermicompost

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Citation

Citation: Okonkwo NN., et al. “Biodegradation of Styrofoam by a Genetically Modified Mold Isolated from a 30 Days Vermicompost". Acta Scientific Microbiology 9.7 (2026): 03-10.

Copyright

Copyright: © 2026 Okonkwo NN., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.