Isolation and identification of low-density polyethylene degrading novel bacterial strains

Plas c bags (Low Density Polyethylene (LDPE) belong to the polymers, which plays a very important role in our daily lives by their diversi ed applica on. However, the accumula on of the plas c bags in the environment cons - tutes a serious problem and a real source for visual nuisance, pollu on of soil and marine environments. Furthermore, their biodegradation was the safest method of breakdown that possibly leaves behind less toxic residues and showed poten al of bio-geo chemical cycling of the substrate. The aim of the present work was the characterization of the isolated bacterial strains from a municipal land ll area of Tlemcen, North West Algeria, which were implicated by the biodegrada on ability of the Low Density Polyethylene. The degradation of the Low Density Polyethylene was inves gated by studying the bacterial growth of the isolated, inoculated on a solid culture medium, which was composed of LDPE as the sole carbon source with and with- out a nitrogen source and the selec on was based by the determination of the produced diameter of hydrolysis clear zone on the surface. Furthermore, the isolated, selected degrading Low Density Polyethylene bacterial ML002 has been iden ed by the study of their morphological, biochemical charac- teris cs and the ampli ca on of the fragment, coding the region of ARN 16S. The use of the API system indicated their belonging to the genus Bacillus Cereus, which has reduced the weight of LDPE by 0.26, 1.28, 1.53% a er 30, 90, 120 days respec vely. Furthermore, the amplified of the fragment, coding the region of ARN 16S by the isolated, selected bacterial ML002 indicated a similarity of 99.394% with Bacillus wiedmannii and Bacillus proteolyticus and 99.293% homology with Bacillus toyonensis, Bacillus cereus and Bacillus thuringiensis.

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Cellulase enzyme catalyst producing bacterial strains from vermicompost and its application in low-density polyethylene degradation

Chemosphere ◽

10.1016/j.chemosphere.2021.132552 ◽

2021 ◽

pp. 132552

Author(s):

Veena Gayathri Krishnaswamy ◽

Rajalakshmi Sridharan ◽

P. Senthil Kumar ◽

Mariyam Jaffer Fathima

Keyword(s):

Low Density Polyethylene ◽

Low Density ◽

Bacterial Strains ◽

Cellulase Enzyme ◽

Enzyme Catalyst

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Ability of Trichoderma hamatum Isolated from Plastics-Polluted Environments to Attack Petroleum-Based, Synthetic Polymer Films

Processes ◽

10.3390/pr8040467 ◽

2020 ◽

Vol 8 (4) ◽

pp. 467

Author(s):

Kateřina Malachová ◽

Čeněk Novotný ◽

Grażyna Adamus ◽

Nadia Lotti ◽

Zuzana Rybková ◽

...

Keyword(s):

Functional Groups ◽

Polymer Surface ◽

Microbial Consortia ◽

Low Density Polyethylene ◽

High Temperature Treatment ◽

Rrna Gene ◽

Its Sequencing ◽

Low Density ◽

Bacterial Strains ◽

Trichoderma Hamatum

Microorganisms colonizing plastic waste material collected in composting-, landfill-, and anaerobic digestion plants were isolated to obtain novel strains maximally adapted to the degradation of plastics due to long-term contact with plastic polymers. Twenty-six bacterial strains were isolated and identified by the 16 S rRNA method, and eighteen strains of yeasts and fungi using 18 S rRNA and the internal transcribed spacer ITS sequencing of the 18 S rRNA gene. In selected strains, the ability to degrade linear low-density polyethylene (LLDPE), low-density polyethylene (LDPE), polystyrene (PS), and polyvinyl chloride (PVC) was tested in aerobic liquid-medium cultures. An oxidative, two-step pretreatment of LLDPE and LDPE using γ- or UV-irradiation followed by a high-temperature treatment was carried out, and the pretreated plastics were also included in the degradation experiments. The respective weight losses after biodegradation by Trichoderma hamatum were: virgin and γ/T90-pretreated LLDPE (2.2 ± 1.2 and 3.9 ± 0.5%), virgin and UV/T60-pretreated LDPE (0.5 ± 0.4 and 1.3 ± 0.4%), and virgin PS (0.9 ± 0.4%). The Fourier transform infrared spectroscopy (FTIR) analysis showed that during the treatment of pretreated LLDPE, T. hamatum attacked low molecular weight LLDPE oligomers, reducing the functional groups (carbonyl C = O), which was paralleled by a slight increase of the molar mass of pretreated LLDPE and a decrease of the dispersity index, as demonstrated by gel permeation chromatography (GPC). Thermogravimetric analysis (TGA) highlighted the formation of functional groups on LLDPE due to polymer pretreatment that favored fungal attack at the polymer surface. The results provide insight into microbial consortia that spontaneously colonize the surface of plastics in various environments and their capability to attack plastic polymers.

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Isolation and identification of low-density polyethylene (LDPE) biodegrading bacteria from waste landfill in Yazd

International Journal of Environmental Studies ◽

10.1080/00207233.2018.1551986 ◽

2018 ◽

Vol 76 (2) ◽

pp. 236-250 ◽

Cited By ~ 2

Author(s):

Asieh Nourollahi ◽

Samaneh Sedighi-Khavidak ◽

Mehdi Mokhtari ◽

Gilda Eslami ◽

Mahbubeh Shiranian

Keyword(s):

Low Density Polyethylene ◽

Low Density ◽

Isolation And Identification ◽

Waste Landfill

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In vitro biodegradation of low-density polyethylene by soil microorganisms

Research Journal of Chemistry and Environment ◽

10.25303/2512rjce4452 ◽

2021 ◽

Vol 25 (12) ◽

pp. 44-52

Author(s):

Lakshmi P. Jayashree ◽

Selvi K. Vanmathi

Keyword(s):

Synthetic Medium ◽

Cell Surface Hydrophobicity ◽

Maximum Growth ◽

Surface Hydrophobicity ◽

Low Density Polyethylene ◽

Bacillus Species ◽

Low Density ◽

Bacterial Strains ◽

Fungal Strains

The accumulation of recalcitrant plastics in the environment, particularly polyethylene, is a major threat to the ecology. Among the different kinds of polyethylene, low-density polyethylene (LDPE) is the most widely used polyethylene. The goal of this work was to isolate and discover a powerful polyethylene degrading microbial strain from plastic waste disposal soil. The bacterial and fungal strains were isolated by enrichment technique and were identified based on the morphological and biochemical characteristics. Further, they were screened individually for their lowdensity polyethylene (LDPE) degrading efficiency by in vitro biodegradation assay. The efficiency of the potent strain to colonize on the LDPE surface and its biodegradation ability were investigated. The degraded products of low-density polyethylene were analysed by FTIR after the biodegradation study which was conducted for a long incubation period by inoculating the selected bacterial strain in synthetic medium (SM) with LDPE as the carbon source. Totally six different bacterial and five different fungal strains were isolated from the polluted soil. Among the bacterial strains, the JSB2, JSB3 and JSB4 and among the fungal strains, JSF1, JSF3 and JSF4 showed maximum growth, more cell surface hydrophobicity and weight loss and they were selected for further studies. The incubation of LDPE films with bacteria and fungi led to the formation of new absorbance bands such as dehydrated dimer of carbonyl group (1720 cm-1), CH3 deformation (1463 cm-1) and C=C conjugation band (862 cm-1). The results inferred that the exogenous addition of these microbes to LDPE contaminated soil causes an enhanced degradation. Among the microbial isolates, Bacillus species showed high degradation.

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