High-density polyethylene (HDPE)-degrading potential bacteria from marine ecosystem of Gulf of Mannar, India

Abstract

Aims: Assessment of high‐density polyethylene (HDPE)‐degrading bacteria isolated from plastic waste dumpsites of Gulf of Mannar. Methods and Results: Rationally, 15 bacteria (GMB1‐GMB15) were isolated by enrichment technique. GMB5 and GMB7 were selected for further studies based on their efficiency to degrade the HDPE and identified as Arthrobacter sp. and Pseudomonas sp., respectively. Assessed weight loss of HDPE after 30 days of incubation was nearly 12% for Arthrobacter sp. and 15% for Pseudomonas sp. The bacterial adhesion to hydrocarbon (BATH) assay showed that the cell surface hydrophobicity of Pseudomonas sp. was higher than Arthrobacter sp. Both fluorescein diacetate hydrolysis and protein content of the biofilm were used to test the viability and protein density of the biomass. Acute peak elevation was observed between 2 and 5 days of inoculation for both bacteria. Fourier transform infrared (FT‐IR) spectrum showed that keto carbonyl bond index (KCBI), Ester carbonyl bond index (ECBI) and Vinyl bond index (VBI) were increased indicating changes in functional group(s) and/or side chain modification confirming the biodegradation. Conclusion: The results pose us to suggest that both Pseudomonas sp. and Arthrobacter sp. were proven efficient to degrade HDPE, albeit the former was more efficacious, yet the ability of latter cannot be neglected. Significance and Impact of the Study: Recent alarm on ecological threats to marine system is dumping plastic waste in the marine ecosystem and coastal arena by anthropogenic activity. In maintenance phase of the plastic‐derived polyethylene waste, the microbial degradation plays a major role; the information accomplished in this work will be the initiating point for the degradation of polyethylene by indigenous bacterial population in the marine ecosystem and provides a novel eco‐friendly solution in eco‐management.

Biodegradation of HDPE by Aspergillus spp. from marine ecosystem of Gulf of Mannar, India

“…The biofilm formation can be influenced by the cellular surface hydrophobicity (Gilan et al, 2004;Balasubramanian et al, 2010). Mineral oil has promoted the hydrophobic interaction between the fungal strains and HDPE surface.…”

Silver Inhibits the Biofilm Formation of <i>Pseudomonas aeruginosa</i>

“…The result revealed that all the tested sub MIC doses of silver exhibited significant biofilm attenuation property compared to control where the organism was grown and allowed to form biofilm in absence of silver (Figure 1). The extent of microbial biofilm formation on test tubes in presence and absence of silver was also measured by determining the amount of total extractable protein [22] [29]. Since it is very difficult to estimate the total microbial populations on the test tube surfaces by conventional plate counting, total protein extraction can be an alternative tool to address the extent of microbial population over there because protein can only be coming from the biotic source like bacteria and not from abiotic source like test tubes.…”

Mechanical and morphological properties of high density polyethylene and polylactide blends

“…Annually, about 500 billion to 1 trillion polythene carrier bags are used around the globe and 25 million tons of synthetic plastics accumulate in the sea coasts and terrestrial environment every year [3]. In particular, approximately 61 thousand tons of plastic wastes found their way in to India in the year 2000 [4]. However, with these drastic rises in the use of plastic materials, a corresponding development of processes for the harmless disposal or degradation of the plastic waste has not been noticed.…”