Biodegradation of polyethylene by the thermophilic bacterium Brevibacillus borstelensis

Abstract

Aim: To select a polyethylene-degrading micro-organism and to study the factors affecting its biodegrading activity. Methods and Results: A thermophilic bacterium Brevibaccillus borstelensis strain 707 (isolated from soil) utilized branched low-density polyethylene as the sole carbon source and degraded it. Incubation of polyethylene with B. borstelensis (30 days, 50°C) reduced its gravimetric and molecular weights by 11 and 30% respectively. Brevibaccillus borstelensis also degraded polyethylene in the presence of mannitol. Biodegradation of u.v. photo-oxidized polyethylene increased with increasing irradiation time. Fourier Transform Infra-Red (FTIR) analysis of photooxidized polyethylene revealed a reduction in carbonyl groups after incubation with the bacteria. Conclusions: This study demonstrates that polyethylene -considered to be inert -can be biodegraded if the right microbial strain is isolated. Enrichment culture methods were effective for isolating a thermophilic bacterium capable of utilizing polyethylene as the sole carbon and energy source. Maximal biodegradation was obtained in combination with photo-oxidation, which showed that carbonyl residues formed by photo-oxidation play a role in biodegradation. Brevibaccillus borstelensis also degraded the CH 2 backbone of nonirradiated polyethylene. Significance and Impact of the Study: Biodegradation of polyethylene by a single bacterial strain contributes to our understanding of the process and the factors affecting polyethylene biodegradation.

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.…”

Temporal variation of microbial population in acclimation and start-up period of a thermophilic desulfurization biofilter

“…Band 18 and 21were identified as Brevibacillus thermoruber (100%) and Brevibacillus borstelensis (99%), respectively. As metabolic products of these thermophilic bacteria, significant amounts of sulfates were generated, which can be precipitated by supplementing the culturing media with ions, leading to insoluble salts (Hadad et al, 2005;Manachini et al, 1985). Band 31 and 34 were closely associated with Bacillus thermophilus (100%), which is widely distributed in soil, hot springs, and ocean sediments, and is capable of oxidizing carbon monoxide aerobically (Nazina et al, 2001).…”

Enhancing Degradation of Low Density Polyethylene Films by Curvularia lunata SG1 Using Particle Swarm Optimization Strategy

“…However, no weight loss was evident in the control experiment where in incubation was carried out at the same temperature for a similar length of time but without C. lunata SG1 (data not shown). 6.2 % weight loss was reported for UV irradiation of 60 h. as compared to untreated LDPE with Bravebacillus brostelensis for 30 days [32]. UV irradiation for 500 h. increased the biodegradation of polyethylene by 25 % using Penicillium simlicissimum YK [33].…”