Biodegradation of Plastics by Pseudomonas spp. Isolated from Soil Samples of Landfills in Khartoum State, Sudan

Abstract

This study was conducted to assess the biodegradation of
plastic bags by Pseudomonas spp. isolated from soil samples collected
from landfills in Khartoum State, Sudan. Soil samples were collected
from three different locations (A = Khartoum landfill, B = Khartoum
North landfill, C = Omdurman landfill). The Identification and
characterizatics of bacteria were done using morphological and
biochemical characterizations. The isolated and standard strains were
added to the plastic bags in liquid media and then incubated in a rotary
shaker for three weeks to allow time for biodegradation. The initial and
final dry weights of plastic before and after incubation in the culture
medium were compared and the percentage of degradation was
calculated. The data were subjected to statistical analysis using
completely randomized design (CRD). Mean separations were estimated
by Duncan multiple range test (DMRT). This work revealed that the
landfill soil is a good source of microbes capable of degrading plastic
materials. The isolated strains (Pseudomonas spp.) were found to degrade
the plastic bags in the range between 76.4 to 84.8 % within three weeks.
Pseudomonas putida was found to degrade the plastic bags up to 85.2 %.
The weight loss in plastic bags’ samples is likely due to active enzymes
produced by the bacteria