Author(s)

A. O. Ogunbayo^*, O. O. Olanipekun, I. A. Adamu

Department of Chemical and Petroleum Engineering, University of Lagos, Yaba, Lagos, Nigeria.

The possibility of microbial degradation of plastic waste was investigated by isolating microorganisms present in dumpsite containing low-density polyethylene (LDP). Aspergillus niger (fungi) and Pseudomonas sp. (bacteria) were identified and subsequently used to biodegrade plastic waste. The medium was made up of 0.2 g of MgSO₄, 1.0 g of KH₂PO₄, 1.0 g of K₂HPO₄, 1.0 g of NH₄NO₃, 0.02 g of CaCl₂, 0.05 g of FeCl₃ in 1000 ml water. 10 ml of the medium containing the bacteria and/or fungi was poured into test tubes and 0.1 g of the plastic sample (Pure water sachet) pre-treated with ethanol was introduced into the tubes. The pH of the medium was adjusted to 7.2, 5.4 and 6.0 for Pseudomonas sp., Aspergillus niger and the mixed culture respectively. Each experiment was carried out aerobically at room temperature and incubated on a rotary shaker at 120 rpm. The weight loss in each experiment was monitored at 10 days interval for 60 days. The total weight loss after 60 days was 7.2%, 12.4%, 15% for degradation with Pseudomonas sp., Aspergillus niger and the mixed culture respectively. From this study it can be inferred that Pseudomonas sp. and Aspergillus niger have the ability to degrade plastics. It can also be inferred that Aspergillus niger degraded plastics better than Pseudomonas sp. and there was synergy between the two microorganisms since the mixed culture gave a higher degradation.

Biodegradation, Synthetic Plastic, Low Density Polyethylene, Pseudomonas sp., Aspergillus niger, Biodegradability

Ogunbayo, A. , Olanipekun, O. and Adamu, I. (2019) Preliminary Studies on the Microbial Degradation of Plastic Waste Using Aspergillus niger and Pseudomonas sp.. Journal of Environmental Protection, 10, 625-631. doi: 10.4236/jep.2019.105037.