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 MgSO 4 , 1.0 g of KH 2 PO 4 , 1.0 g of K 2 HPO 4 , 1.0 g of NH 4 NO 3 , 0.02 g of CaCl 2 , 0.05 g of FeCl 3 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.

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The microbial activities and the biodegradation-abilities of undefined consortium in contaminated soils in the Niger Delta of Nigeria were studied. The Respirametry technique was adopted to evaluate the microbial activities while the soils were incubated with 2% () ν ν crude oil in mineral salt medium at 37˚C in three stages of two weeks each in a shake flask. At the end of the last phase, components of the crude oil degraded by the undefined consortium in the soils were identified with the gas chromatographic techniques. The consortia of the different samples studied showed different degree of capacities on the crude oil, removing a large number of components of the crude oil, making the areas potentially suitable for in-situ bioremediation.

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