Screening of plastic degrading bacteria from dumped soil area

Abstract

Plastic wastes accumulating in the environment are posing an ever increasing ecological threat. Plastics that are biodegradable can be considered environment friendly, they have an increasing range of potential application and are driven by the growing use of plastics in packaging. In this study, the biodegradation of polythene bag was analyzed 1 month of incubation in liquid culture method. Microbial counts in the degrading materials were recorded up to 0.0278×109 per gram for total heterotrophic bacteria. The microbial species found associated with the degrading materials were identified as two Gram positive and five Gram negative bacteria. The microbial species associated with the polythene materials were identified as Bacillus subtilis, Bacillus amylolyticus, Arthobacter defluvii. The efficacy of microbes in the degradation of plastics were analyzed in liquid (shaker) culture method, among the bacteria Bacillus amylolyticus degrades plastic more in 1 month (30% weight loss/month) period compared to others and lowest degradation rate was observed in case of Bacillus subtilis (20% weight loss/month). This work reveals that Bacillus amylolyticus posses greater potential to degrade plastics when compared with other bacteria.