Isolation of Fusarium sp. AF4 from sewage sludge, with the ability to adhere the surface of polyethylene
Aamer Ali Shah, Fariha Hasan, Abdul Hameed, Javed Iqbal Akhter
Microbiology Research Laboratory, Department of Microbiology, Quaid-i-Azam University, Islamabad, Pakistan.
Plastic materials like Polyethylene (PE) are the potential source of environmental pollution. Their presence in soil causes infertility of soil, preventing degradation of other normal substances, in addition to which it presents a danger to animal life. In the present study, a fungal strain was isolated from sewage sludge capable of adhering to the surface of PE pieces, through enrichment technique. A thick network of fungal hyphae was observed on the surface of the plastic pieces under light microscope. The fungal strain was identified as Fusarium sp. AF4. A visible increase in growth of the Fusarium sp. AF4 was observed on the surface of PE pieces, when cultured in basal salts medium at 30°C and 150 rpm, for 2 months. When the PE pieces were observed through scanning electron microscope, some changes, like appearance of pits, cracks, and erosion, were detected. CO2 evolution as a result of PE biodegradation was calculated gravimetrically by Sturm Test. About 1.85 g/l of CO2 was produced in case of test, whereas, 0.45 g/l in case of control. The biomass was also higher in case test as compared to control. These observations indicated that Fusarium sp. AF4 have the ability to degrade polyethylene.
Keywords: Biodegradation, Fusarium sp. AF4, polyethylene (PE), Scanning electron microscopy, sturm test.