Biofilm development of the polyethylene-degrading bacterium Rhodococcus ruber

Abstract

We have recently isolated a biofilm-producing strain (C208) of Rhodococcus ruber that degraded polyethylene at a rate of 0.86% per week (r2=0.98). Strain C208 adheres to polyethylene immediately upon exposure to the polyolefin. This initial biofilm differentiates (in a stepwise process that lasts about 20 h) into cell-aggregation-forming microcolonies. Further organization yields "mushroom-like" three-dimensional structures on the mature biofilm. The ratio between the population densities of the biofilm and the planktonic C208 cells after 10 days of incubation was about 60:1, indicating a high preference for the biofilm mode of growth. Analysis of extracellular polymeric substances (EPS) in the biofilm of C208 revealed that the polysaccharides level was up to 2.5 folds higher than that of the protein. The biofilm showed a high viability even after 60 days of incubation, apparently due to polyethylene biodegradation.

Biodegradation of Low Density Polythene (LDPE) by Pseudomonas Species

“…Several previous studies have reported on biodegradation of polythene by bacterial [2,11] and fungal species [2,4,13] It has been reported that Pseudomonas spp. degrade polythene bags made of LDPE in natural as well as artificial environment.…”

A reversible functional supramolecular material formed by host–guest inclusion

“…One is the search for microorganisms for the degradation of polymers. [4][5][6] However, since the presence of polymers in nature's evolution is very short, it is very hard to nd new organisms capable of degrading synthetic polymers in nature. Another approach is the preparation of environmentally friendly polymers, 7-9 which can be easily degraded by microorganisms.…”

Biodegradation of Synthetic Plastics

“…[19] Polyethylene Brevibacillus borstelensis [36] Rhodococcus rubber [37] Penicillium simplicissimum YK [9] Brevibacillus borstelen [38] Penicillium frequentans Bacillus mycoides [10] Aspergillus niger Penicillium pinophilium [11] Penicillium pinophilium Aspergillus niger Cliocladium virens Penicillium chrysosporium [12] Bacillus sphericus Bacillus cereus [13] Streptomyces spp. • 생물적 요인: 세포 외 효소분비, 소수성 표면으로의 부착 정도, 바이오 계면활성제 등.…”