Dataset Information

Biodegradation efficacy of soil inherent novel sp. Bacillus tropicus (MK318648) onto low density polyethylene matrix

ABSTRACT: The biodegradation of low density polyethylene (LDPE) was studied by employing a microbial strain isolated from the dumping site soil. The bacterium strain was identified as Bacillus tropicus (Gen Bank Accession no: MK318648) by 16S rRNA sequencing. The growth of the strain was observed on virgin LDPE during the biodegradation process. The change in properties of LDPE films before and after bacterial strain incubation was observed by FTIR, SEM, AFM, contact angle, mechanical and optical testing. Loss in mechanical properties and changes in optical properties of the polymer matrix was observed. Weight reduction by 10.15% and fall in the value of tensile strength, elongation at break, tear strength, Young’s Modulus, hardness and stiffness to 8.59 MPa, 10.85 mm, 69.18 N, 272.36, 37.6 Shor D and 10,672.21 N/m respectively were observed after 40 days of incubation. The transparency and haze percentage were also changed to 93.7% and 18.6% respectively after the study period. The pH of the media was measured during incubation to evaluate the change due to formation of different extracellular and intracellular enzymes excreted by the strain. Hence, Bacillus tropicus could be an efficient microorganism to degrade 10-micron thickness LDPE films, thereby preventing its harmful impacts in the environment.

SUBMITTER: Samanta S

PROVIDER: S-EPMC7532934 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Exploring the catabolic repertoire of natural bacteria for biodegradation of plastics is one of the priority areas of biotechnology research. Low Density Polyethylene (LDPE) is recalcitrant and poses serious threats to our environment. The present study explored the LDPE biodegradation potential of aerobic bacteria enriched from municipal waste dumpsite and bentonite based drilling fluids from a deep subsurface drilling operation. Considerable bacterial growth coupled with significant weight loss of the LDPE beads (∼8%), change in pH to acidic condition and biofilm cell growth around the beads (CFU count 105-106/cm2) were noted for two samples (P and DF2). The enriched microbial consortia thus obtained displayed high (65-90%) cell surface hydrophobicity, confirming their potential toward LDPE adhesion as well as biofilm formation. Two LDPE degrading bacterial strains affiliated to Stenotrophomonas sp. and Achromobacter sp. were isolated as pure culture from P and DF2 enrichments. 16S rRNA gene sequences of these isolates indicated their taxonomic novelty. Further biodegradation studies provided strong evidence toward the LDPE metabolizing ability of these two organisms. Atomic Fore Microscopy (AFM) and Scanning Electron Microscopy (SEM) revealed considerable damage (in terms of formation of cracks, grooves, etc.) on the micrometric surface of the LDPE film. Analysis of the average roughness (Ra), root mean square roughness (Rq), average height (Rz), maximum peak height (Rp), and maximum valley depth (Rv) (nano-roughness parameters) through AFM indicated 2-3 fold increase in nano-roughness of the LDPE film. FTIR analysis suggested incorporation of alkoxy (1000-1090 cm-1), acyl (1220 cm-1), nitro (1500-1600 cm-1), carbonyl (1720 cm-1) groups into the carbon backbone, formation of N-O stretching (1360 cm-1) and chain scission (905 cm-1) in the microbially treated LDPEs. Increase in carbonyl index (15-20 fold), double bond index (1.5-2 fold) and terminal double bond index (30-40 fold) confirmed that biodegraded LDPEs had undergone oxidation, vinylene formation and chain scission. The data suggested that oxidation and dehydrogenation could be the key steps allowing formation of low molecular weight products suitable for their further mineralization by the test bacteria. The study highlighted LDPE degrading ability of natural bacteria and provided the opportunity for their development in plastic remediation process.

Dataset Information

Biodegradation efficacy of soil inherent novel sp. Bacillus tropicus (MK318648) onto low density polyethylene matrix

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets