Bacteria-based polythene degradation products: GC-MS analysis and toxicity testing

Isolation and characterization of bio-prospecting gut strains Bacillus safensis CGK192 and Bacillus australimaris CGK221 for plastic (HDPE) degradation

The present work reports the application of novel gut strains Bacillus safensis CGK192 (Accession No. OM658336) and Bacillus australimaris CGK221 (Accession No. OM658338) in the biological degradation of synthetic polymer i.e., high-density polyethylene (HDPE). The biodegradation assay based on polymer weight loss was conducted under laboratory conditions for a period of 90 days along with regular evaluation of bacterial biomass in terms of total protein content and viable cells (CFU/cm2). Notably, both strains achieved significant weight reduction for HDPE films without any physical or chemical pretreatment in comparison to control. Hydrophobicity and biosurfactant characterization were also done in order to assess strains ability to form bacterial biofilm over the polymer surface. The post-degradation characterization of HDPE was also performed to confirm degradation using analytical techniques such as Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Field emission scanning electronic microscopy (FE-SEM) coupled with energy dispersive X-ray (EDX), and Gas chromatography-mass spectrometry (GC-MS). Interestingly strain CGK221 was found to be more efficient in forming biofilm over polymer surface as indicated by lower half-life (i.e., 0.00032 day-1) and higher carbonyl index in comparison to strain CGK192. The findings reflect the ability of our strains to develop biofilm and introduce an oxygenic functional group into the polymer surface, thereby making it more susceptible to degradation.

Enterobacter cloacae-mediated polymer biodegradation: in-silico analysis predicts broad spectrum degradation potential by Alkane monooxygenase

Plastic pollution poses a significant environmental challenge. In this study, the strain Enterobacter cloacae O5-E, a bacterium displaying polyethylene-degrading capabilities was isolated. Over a span of 30 days, analytical techniques including x-ray diffractometry, scanning electron microscopy, optical profilometry, hardness testing and mass spectrometric analysis were employed to examine alterations in the polymer. Results revealed an 11.48% reduction in crystallinity, a 50% decrease in hardness, and a substantial 25-fold increase in surface roughness resulting from the pits and cracks introduced in the polymer by the isolate. Additionally, the presence of degradational by-products revealed via gas chromatography ascertains the steady progression of degradation. Further, recognizing the pivotal role of alkane monooxygenase in plastic degradation, the study expanded to detect this enzyme in the isolate molecularly. Molecular docking studies were conducted to assess the enzyme's affinity with various polymers, demonstrating notable binding capability with most polymers, especially with polyurethane (- 5.47 kcal/mol). These findings highlight the biodegradation potential of Enterobacter cloacae O5-E and the crucial involvement of alkane monooxygenase in the initial steps of the degradation process, offering a promising avenue to address the global plastic pollution crisis.

Analytical strategy to assess the microbial degradation of poly(butylene-adipate-co-terephthalate)/poly(lactic acid) films

Plastic is widely used in agricultural applications, but its waste has an adverse environmental impact and a long-term detrimental effect. The development of biodegradable plastics for agricultural use is increasing to mitigate plastic waste. The most commonly used biodegradable plastic is poly(butylene adipate co-terephthalate)/poly(lactic acid) (PBAT/PLA) polymer. In this study, an analytical procedure based on dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography-mass spectrometry (GC-MS) in combination with chemometrics has been optimized to assess the degradation level of PBAT/PLA films by monitoring their characteristic degradation products. Carboxylic acids (benzoic, phthalic, adipic, heptanoic, and octadecanoic acids) and 1,4-butanediol have been found to be potential markers of PBAT/PLA degradation. The DLLME-GC-MS analytical approach has been applied for the first time to assess the degradation efficiency of several microorganisms used as degradation accelerators of PBAT/PLA based on the assigned potential markers. This analytical strategy has shown higher sensitivity and precision than standard techniques, such as elemental analysis, allowing us to detect low degradation levels.

Significance of landfill microbial communities in biodegradation of polyethylene and nylon 6,6 microplastics

Plastic pollution, particularly microplastics, poses a significant environmental challenge. This study aimed to address the urgent need for sustainable solutions to manage plastic waste. The degradation of polyethylene microplastics (PEMPs) and nylon 6,6 microplastics (NMPs) were investigated using bacterial culture isolates, isolated from a municipal landfill site and identified through 16 S rDNA as well as metagenomics techniques.The study demonstrated for the first time along with degradation mechanism. The isolates identified as Achromobacter xylosoxidans and mixed culture species in dominance of Pulmonis sp. were used to degrade PEMPs and NMPs. Achromobacter xylosoxidans reduced microplastic's dry weight by 26.7% (PEMPs) and 21.3% (NMPs) in 40 days, while the mixed culture achieved weight reductions of 19.3% (PEMPs) and 20% (NMPs). The release of enzymes, laccase and peroxidases revealed C-C bond cleavage and reduced polymer chain length. The thermal studies (TGA and DSC) revealed changes in the thermal stability and transition characteristics of microplastics. The structural alterations on PEMPs and NMPs were recorded by FTIR analysis. Byproducts such as alkanes, esters, aromatic compounds and carboxylic acids released were identified by GC-MS. These results suggest the effectiveness of bacterial isolates in degrading PEMPs and NMPs, with potential for sustainable plastic waste management solutions.

The escalated potential of the novel isolate Bacillus cereus NJD1 for effective biodegradation of LDPE films without pre-treatment

This study focused on the biodegradation of LDPE films using a novel isolate of Bacillus obtained from soil samples collected from a 20-year-old plastic waste dump. The aim was to evaluate the biodegradability of LDPE films treated with this bacterial isolate. The results indicated a 43% weight loss of LDPE films within 120 days of treatment. The biodegradability of LDPE films was confirmed through various testing methods, including BATH, FDA, CO₂ evolution tests, and changes in total cell growth count, protein content, viability, p^H of the medium, and release of microplastics. The bacterial enzymes, including laccases, lipases, and proteases, were also identified. SEM analysis revealed biofilm formation and surface changes in treated LDPE films, while EDAX analysis showed a reduction in carbon elements. AFM analysis demonstrated differences in roughness compared to the control. Furthermore, wettability increased and tensile strength decreased, confirming the biodegradation of the isolate. FTIR spectral analysis showed changes in skeletal vibrations, such as stretches and bends, in the linear structure of polyethylene. FTIR imaging and GC-MS analysis also confirmed the biodegradation of LDPE films by the novel isolate identified as Bacillus cereus strain NJD1. The study highlights the potentiality of the bacterial isolate for safe and effective microbial remediation of LDPE films.

Assembly strategies for polyethylene-degrading microbial consortia based on the combination of omics tools and the "Plastisphere"

Numerous microorganisms and other invertebrates that are able to degrade polyethylene (PE) have been reported. However, studies on PE biodegradation are still limited due to its extreme stability and the lack of explicit insights into the mechanisms and efficient enzymes involved in its metabolism by microorganisms. In this review, current studies of PE biodegradation, including the fundamental stages, important microorganisms and enzymes, and functional microbial consortia, were examined. Considering the bottlenecks in the construction of PE-degrading consortia, a combination of top-down and bottom-up approaches is proposed to identify the mechanisms and metabolites of PE degradation, related enzymes, and efficient synthetic microbial consortia. In addition, the exploration of the plastisphere based on omics tools is proposed as a future principal research direction for the construction of synthetic microbial consortia for PE degradation. Combining chemical and biological upcycling processes for PE waste could be widely applied in various fields to promote a sustainable environment.

Unveiling the potential of Lichtheimia ramosa AJP11 for myco-transformation of polystyrene sulfonate and its driving molecular mechanism

Plastic pollution is a major environmental concern due to its deleterious effects on various ecosystems. The limitations and shortcomings of waste management strategies has led to the over-accumulation of plastic waste, mainly comprised of single-use plastics, such as polystyrene (PS). Considering the advantages of biotransformation over the other plastic disposal methods, it has become a major focus of the modern research. Biotransformation of plastics involves its microbial hydrolysis into short chain oligomers and monomers that are eventually assimilated as carbon source by the microbes leading to the release of CO₂. As fungi are known to possess multifarious and highly regulated enzyme system capable of utilizing diverse nutrient sources, the present study explored the potential of Lichtheimia ramosa AJP11 towards myco-transformation of polystyrene sulfonate (PSS), a structural analogue of polystyrene (PS). During the 30-day incubation period of L. ramosa AJP11 in minimal salt medium (MSM)+1% PSS, the fungus showed 41.6% increment in its fresh weight biomass, indicating the utilization of PSS as sole carbon source. Further analysis revealed the generation of various reaction intermediates such as alkanes and fatty acids, crucial for the continuum of fungal metabolic pathways. Moreover, detection of PS oligomers such as cyclohexane and 2,4-DTBP confirmed the myco-transformation of PSS. The extracellular fungal protein profile showed considerable overexpression of a 14.4 kDa protein, characterized to be a hydrophobic surface binding (Hsb) protein, which is hypothesized to adsorb onto the PSS to facilitate its transformation. Further, in silico analysis of Hsb protein indicated it to be an amphiphilic α-helical protein with ability to bind styrene sulfonate unit via both hydrogen and hydrophobic interactions, with a binding energy of -5.02 kcal mol^-1. These findings open new avenues for over expression of Hsb under controlled reactor conditions to accelerate the PS waste disposal.

Microbial degradation of virgin polyethylene by bacteria isolated from a landfill site

Abstract

In this study we evaluate the extent of degradation of high-density polyethylene by bacterial isolates obtained from landfill. The microorganisms are isolated from plastic wastes deposited in the landfill for 2–3 years and 17 years. Experiments are conducted under laboratory conditions to degrade virgin high-density polyethylene used in the manufacture of packaging materials. Gravimetric and GC–MS analyses are performed to describe polyethylene decomposition. Of all the bacterial isolates tested, the degradation of polyethylene by Bacillus cereus is the highest, 1.78%, based on weight loss. On the other hand, degradation by Pseudomonas tuomurensis is 0.3%. Degradation products are detected, confirming the progressive degradation of the plastic. The hydrocarbons with single and double bonds are observed most frequently. Our study provides insight into the microbial biodegradation of polyethylene in the environment and contributes to the understanding of the biodegradation processes that may occur in landfills and their progress.

Article Highlights

Oxidative degradation of UV-irradiated polyethylene by laccase-mediator system

Polyethylene (PE) is one of the most widely used plastics. However, the chemical inertness, inefficient recycling, and random landfilling of PE waste have caused serious pollution to the natural environment. In this study, a series of laccase-mediator systems (LMS) were constructed by combination of two laccases from Botrytis aclada (BaLac) and Bacillus subtilis (BsLac) with three synthetic mediators (ABTS, HBT, and TEMPO) to oxidize LDPE films (UVPE) pretreated with high-temperature UV irradiation. Scanning electron microscopy showed aging phenomena such as etching, fragmentation, and cracking on the surface of the UVPE films after LMS incubation. The FTIR results showed that LMS-UVPE added new oxygen-containing functional groups such as -OH, -CO, and CC. High-temperature gel chromatography confirmed that the average reduction in weight-average molecular weight (Mw) was approximately 40% for the BaLac experimental group. GC-MS analysis showed the presence of oxygen-containing products, such as aldehydes, ketones, and alcohols, in the reaction mixture. To verify the oxidation process UVPE degradation by LMS, we inferred three possible pathways by combined analysis of the oxidation products of LMS on UVPE and model substrates oleic acid and squalene.

Environmental impacts of hazardous waste, and management strategies to reconcile circular economy and eco-sustainability

The rise in living standards and the continuous development in the global economy led to the depletion of resources and increased waste generation per capita. This waste might posture a significant threat to human health or the environmental matrices (water, air, soil) when inadequately treated, transported, stored, or managed/disposed of. Therefore, effective waste management in an economically viable and environmentally friendly way has become meaningful. Prominent technology is the need of the day for circular economy and sustainable development to reduce the speed of depletion in resources and produce an alternative means for the future demands in the different sectors of science and technology. In order to meet the potential requirements for energy production or producing secondary raw material, solid waste may be the prime source. The activities of living organisms convert waste products in one form or another in which electronic waste (e-waste) is a modern-day problem that is growing by leaps and bounds. The disposal protocols of the e-waste management need to be given proper attention to avoid its hazardous impacts. The e-waste is obtained from any equipment or devices that run by electricity or batteries like laptops, palmtops, computers, televisions, mobile phones, digital video discs (DVD), and many more. E-waste is one of the rapidly growing causes of world pollution today. Plenty of research is available in the scientific literature, which shows different approaches being set up and followed to manage and dispose of waste products. These strategies to manage waste products designed by the states all over the globe revolves around minimal production, authentic techniques for the management of waste produced, reuse and recycling, etc. The virtual survey of the available literature on waste management shows that it lacks specificity regarding the management of waste products parallel to ecological sustainability. The presented review covers the sources, potential environmental impacts, and highlights the importance of waste management strategies to provide the latest and updated knowledge. The review also put forward the countermeasures that need to be taken on national and International levels addressing the sensitive issue of waste management.

Marine bacteria-based polyvinyl chloride (PVC) degradation by-products: Toxicity analysis on Vigna radiata and edible seaweed Ulva lactuca

Biodegradation of polyvinyl chloride (PVC) by marine bacteria is a sustainable approach that leads to the production of different by-products but their toxicity needs to be evaluated. In the present study, polyvinyl chloride degradation products (PVCDP) produced by three marine bacterial isolates (T-1.3, BP-4.3 and S-237) in the culture supernatant were evaluated for toxicity on the germination of Vigna radiata and growth of Ulva lactuca. A total of 24 compounds comprising of benzene, fatty acid, ether, ester and plastic stabilizer (tris (2, 4-di-tert-butylphenyl) phosphate) were identified by GC-MS using diethyl ether solvent extraction from the supernatant. The per cent germination rate of the seed treated with PVCDP showed no significant effect but germination index and elongation inhibition rate were influenced significantly by PVCDP treatments. In seaweed (U. lactuca), PVCDP showed improvement in the daily growth rate. After ten days of treatment with PVCDP, pigment contents were improved in seaweed and PVCDP (2%) of isolate T-1.3 recorded the highest chlorophyll-a and chlorophyll-b.

Fungal bioremediation of polyethylene: Challenges and perspectives

Plastics have become ubiquitous in both their adoption as materials and as environmental contaminants. Widespread pollution of these versatile, man-made and largely petroleum-derived polymers has resulted from their long-term mass production, inappropriate disposal and inadequate end of life management. Polyethylene (PE) is at the forefront of this problem, accounting for one-third of plastic demand in Europe in part due to its extensive use in packaging. Current recycling and incineration processes do not represent sustainable solutions to tackle plastic waste, especially once it becomes littered, and the development of new waste-management and remediation technologies are needed. Mycoremediation (fungal-based biodegradation) of PE has been the topic of several studies over the last two decades. The utility of these studies is limited by an inconclusive definition of biodegradation and a lack of knowledge regarding the biological systems responsible. This review highlights relevant features of fungi as potential bioremediation agents, before discussing the evidence for fungal biodegradation of both high- and low-density PE. An up-to-date perspective on mycoremediation as a future solution to PE waste is provided.

Assessment of polyethylene degradation by biosurfactant producing ligninolytic bacterium

Accumulation of plastic waste has become an environmental threat and a global problem. In this research, polyethylene degrading ligninolytic bacteria were isolated from plastic waste polluted soil. Two bacterial isolates, namely PE2 and PE3 have been obtained from the soil samples. Polyethylene degrading ability of the isolates has been assessed individually in a synthetic media containing polyethylene as a carbon source. The results indicated that maximum weight reduction of polyethylene (6.68%) was found in PE3 inoculated media after thirty days of incubation. Fourier Transform Infrared Spectroscopic results showed the appearance of carbonyl peaks. 16S rRNA gene sequencing studies revealed that the potential isolate PE3 belongs to the genus Bacillus and it was named Bacillus sp. strain PE3. From the scanning electron microscopic results, it is inferred that Bacillus sp. strain PE3 could colonize on the polyethylene surface and form a biofilm. Besides, the viable Bacillus sp. strain PE3 on polyethylene surface was confirmed by fluorescence microscopic analysis. Alkanes and fatty acids were identified in the degraded products by gas chromatography-mass spectrometer analysis. From the results of native polyacrylamide gel electrophoresis, the activities of laccase and lignin peroxidase were noticed. Furthermore, extracellular production of biosurfactant has been observed in the Bacillus sp. strain PE3 inoculated mineral salt media and synthetic media with glucose and polyethylene as the carbon source respectively. The characterization studies of crude biosurfactant have confirmed that lipopeptide nature biosurfactant. The present study demonstrates that the ligninolytic enzymes laccase, lignin peroxidase, and lipopeptide type biosurfactant are produced by Bacillus sp. strain PE3 in the media with polyethylene as a carbon source.

Challenges in biodegradation of non-degradable thermoplastic waste: From environmental impact to operational readiness

Non-degradable plastics such as polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) are among the most generated plastic wastes in municipal and industrial waste streams. The mismanagement of abandoned plastics and toxic plastic additives have threatened marine and land fauna as well as human beings for several decades. The available thermal processes can degrade plastic at pilot- and commercial-scale. However, they are energy-intensive and can generate toxic gases. Degradation of plastic waste with the help of live microorganisms (biodegradation) is an eco- and environmentally friendly method for plastic degradation, although the slow processing time and low degradation rate still hinder its applications at pilot- and large-scale. In this review, the advantages and limitations of current plastic degradation methods, their technology readiness levels (TRL), biodegradation mechanisms and the associated challenges in biodegradation are assessed in detail. Based on this analysis, a path toward an efficient and greener way toward degradation of non-recyclable single-use PE, PP, PS and PET plastic is proposed.

Plastic biodegradation: Frontline microbes and their enzymes

Plastic polymers with different properties have been developed in the last 150 years to replace materials such as wood, glass and metals across various applications. Nevertheless, the distinct properties which make plastic desirable for our daily use also threaten our planet's sustainability. Plastics are resilient, non-reactive and most importantly, non-biodegradable. Hence, there has been an exponential increase in plastic waste generation, which has since been recognised as a global environmental threat. Plastic wastes have adversely affected life on earth, primarily through their undesirable accumulation in landfills, leaching into the soil, increased greenhouse gas emission, etc. Even more damaging is their impact on the aquatic ecosystems as they cause entanglement, ingestion and intestinal blockage in aquatic animals. Furthermore, plastics, especially in the microplastic form, have also been found to interfere with chemical interaction between marine organisms, to cause intrinsic toxicity by leaching, and by absorbing persistent organic contaminants as well as pathogens. The current methods for eliminating these wastes (incineration, landfilling, and recycling) come at massive costs, are unsustainable, and put more burden on our environment. Thus, recent focus has been placed more on the potential of biological systems to degrade synthetic plastics. In this regard, some insects, bacteria and fungi have been shown to ingest these polymers and convert them into environmentally friendly carbon compounds. Hence, in the light of recent literature, this review emphasises the multifaceted roles played by microorganisms in this process. The current understanding of the roles played by actinomycetes, algae, bacteria, fungi and their enzymes in enhancing the degradation of synthetic plastics are reviewed, with special focus on their modes of action and probable enzymatic mechanisms. Besides, key areas for further exploration, such as the manipulation of microorganisms through molecular cloning, modification of enzymatic characteristics and metabolic pathway design, are also highlighted.

Biodegradation of Polyethylene by Enterobacter sp. D1 from the Guts of Wax Moth Galleria mellonella

Plastic polymers are widely used in agriculture, industry, and our daily life because of their convenient and economic properties. However, pollution caused by plastic polymers, especially polyethylene (PE), affects both animal and human health when they aggregate in the environment, as they are not easily degraded under natural conditions. In this study, Enterobacter sp. D1 was isolated from the guts of wax moth (Galleria mellonella). Microbial colonies formed around a PE film after 14 days of cultivation with D1. Roughness, depressions, and cracks were detected on the surface of the PE film by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Fourier transform infrared spectroscopy (FTIR) showed the presence of carbonyl functional groups and ether groups on the PE film that was treated with D1. Liquid chromatography-tandem mass spectrometry (LC-MS) also revealed that the contents of certain alcohols, esters, and acids were increased as a result of the D1 treatment, indicating that oxidation reaction occurred on the surface of the PE film treated with D1 bacteria. These observations confirmed that D1 bacteria has an ability to degrade PE.

Gas chromatography-Mass Spectra analysis and deleterious potential of fungal based polythene-degradation products

Polythene-degradation products (PE-DPs) produced due to two most efficient polythene degrading fungal isolates (Aspergillus terreus strain MANF1/WL and Aspergillus sydowii strain PNPF15/TS) after 60 days of incubation at ambient temperature with continuous shaking were analyzed by employing GC-MS method. Total 24 PE-DPs were recorded in total 4 samples i) control (pH 3.5), ii) Treatment of Aspergillus terreus strain MANF1/WL (pH 3.5), iii) control (pH 9.5) and iv) Treatment of Aspergillus sydowii strain PNP15/TS (pH 9.5). To check the deleterious status of PE-DPs using both the elite fungal isolates at in vitro level, two living systems (Sorghum and Tiger shark) were used. The percent germination rate of sorghum seeds were found unaffected with PE-DPs of both elite fungi. PE-DPs of both the fungal isolates exhibited maximum germination index at 50%. Whereas, highest elongation inhibition rate (34.75 ± 7.10) was reported with PE-DPs of Aspergillus terreus strain MANF1/WL. In case of animals system, no mortality of the Tiger sharks was documented after fifteen days of the treatment.

Destabilization of polyethylene and polyvinylchloride structure by marine bacterial strain

Plastics are recalcitrant and inert to degrade, and destabilization leads to accumulate in the terrestrial and marine ecosystems; need for the development of strategies for reducing these plastic wastes in a sustainable manner would be revolutionary. We studied the bacterial adherence, degradation and destabilization of polyvinylchloride (PVC), low-density polyethylene (LDPE), and high-density polyethylene (HDPE) by marine bacterial strain AIIW2 by a series of analytical and microscopic observations over 3 months. Based on 16S rRNA gene sequence and the phylogenetic analysis of the strain AIIW2, it showed 97.39% similarity with Bacillus species. Degradation of plastics was determined by the weight loss after 90 days with bacterial strain which detected up to 0.26 ± 0.02, 0.96 ± 0.02, and 1.0 ± 0.01% for PVC, LDPE, and HDPE films, respectively over initial weights. The mineralization of plastic film was found to be maximum in LDPE followed by HDPE and PVC. Bacterial interaction had increased roughness and deteriorated the surface of plastics which is revealed by the scanning electron microscope and atomic force microscope. Bending vibrations of the alkane rock chain (-CH₂ and -CH₃) and carbonyl (-CO) regions in LDPE and HDPE films, while there was slight stretching in the hydroxyl (-OH) regions of carboxylic acid in PVC which is evidenced through Fourier transform infrared spectral studies, suggested the oxidative activities of the bacteria. Though, the bacterial activity was higher on the LDPE and HDPE than PVC film which may be due to the presence of chlorine atom in PVC structure making it more versatile. The results of the present study revealed the ability of marine bacterial strain for instigating their colonization over plastic films and deteriorating the polymeric structure.

Rhizosphere of Avicennia marina (Forsk.) Vierh. as a landmark for polythene degrading bacteria

Due to high durability, cheap cost, and ease of manufacture, 311 million tons of plastic-based products are manufactured around the globe per annum. The slow/least rate of plastic degradation leads to generation of million tons of plastic waste per annum, which is of great environmental concern. Of the total plastic waste generated, polythene shared about 64 %. Various methods are available in the literature to tackle with the plastic waste, and biodegradation is considered as the most accepted, eco-friendly, and cost-effective method of polythene waste disposal. In the present study, an attempt has been made to isolate, screen, and characterize the most efficient polythene degrading bacteria by using rhizosphere soil of Avicennia marina as a landmark. From 12 localities along the west coast of India, a total of 123 bacterial isolates were recorded. Maximum percent weight loss (% WL; 21.87 ± 6.37 %) was recorded with VASB14 at pH 3.5 after 2 months of shaking at room temperature. Maximum percent weight gain (13.87 ± 3.6 %) was reported with MANGB5 at pH 7. Maximum percent loss in tensile strength (% loss in TS; 87.50 ± 4.8 %) was documented with VASB1 at pH 9.5. The results based on the % loss in TS were only reproducible. Further, the level of degradation was confirmed by scanning electron microscopic (SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. In SEM analysis, scions/crakes were found on the surface of the degraded polythene, and mass of bacterial cell was also recorded on the weight-gained polythene strips. Maximum reduction in carbonyl index (4.14 %) was recorded in untreated polythene strip with Lysinibacillus fusiformis strain VASB14/WL. Based on 16S ribosomal RNA (rRNA) gene sequence homology, the most efficient polythene degrading bacteria were identified as L. fusiformis strainVASB14/WL and Bacillus cereus strain VASB1/TS.