title: Microbial degradation of high impact polystyrene (HIPS), an e-plastic with decabromodiphenyl oxide and antimony trioxide.
abstract: Accumulation of electronic waste has increased catastrophically and out of that various plastic resins constitute one of the leading thrown out materials in the electronic machinery. Enrichment medium, containing high impact polystyrene (HIPS) with decabromodiphenyl oxide and antimony trioxide as sole carbon source, was used to isolate microbial cultures. The viability of these cultures in the e-plastic containing mineral medium was further confirmed by triphenyl tetrazolium chloride (TTC) reduction test. Four cultures were identified by 16S rRNA sequencing as Enterobacter sp., Citrobacter sedlakii, Alcaligenes sp. and Brevundimonas diminuta. Biodegradation experiments were carried out in flask level and gelatin supplementation (0.1% w/v) along with HIPS had increased the degradation rate to a maximum of 12.4% (w/w) within 30days. This is the first report for this kind of material. The comparison of FTIR, NMR, and TGA analysis of original and degraded e-plastic films revealed structural changes under microbial treatment. Polystyrene degradation intermediates in the culture supernatant were also detected using HPLC analysis. The gravity of biodegradation was validated by morphological changes under scanning electron microscope. All isolates displayed depolymerase activity to substantiate enzymatic degradation of e-plastic.
authors.affiliation: Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala, India.
authors.forename: Vini C
authors.initials: VC
authors.lastname: Sekhar
authors.affiliation: Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala, India. Electronic address: madhavan85@hotmail.com.
authors.forename: K Madhavan
authors.initials: KM
authors.lastname: Nampoothiri
authors.affiliation: Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala, India.
authors.forename: Arya J
authors.initials: AJ
authors.lastname: Mohan
authors.affiliation: Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala, India.
authors.forename: Nimisha R
authors.initials: NR
authors.lastname: Nair
authors.affiliation: Bio-Fuels Division (BFD), CSIR-Indian Institute of Petroleum (IIP), Dehradun, Uttarakhand 248005, India.
authors.forename: Thallada
authors.initials: T
authors.lastname: Bhaskar
authors.affiliation: Biotechnology Division, CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Trivandrum 695 019, Kerala, India.
authors.forename: Ashok
authors.initials: A
authors.lastname: Pandey
mesh_terms: D000965:Antimony / Q000737:chemistry*; D001419:Bacteria / Q000201:enzymology / Q000378:metabolism; D001673:Biodegradation, Environmental; D018441:Biofilms; D018533:Biomass; D059029:Electronic Waste; D055768:Halogenated Diphenyl Ethers / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D010084:Oxidation-Reduction; D010969:Plastics; D011137:Polystyrenes / Q000737:chemistry / Q000378:metabolism*; D012336:RNA, Ribosomal, 16S / Q000032:analysis
chemical_list: D055768:Halogenated Diphenyl Ethers; D010969:Plastics; D011137:Polystyrenes; D012336:RNA, Ribosomal, 16S; D000965:Antimony; C010902:decabromobiphenyl ether; C037554:antimony trioxide
keywords: Biodegradation; Depolymerase; High impact polystyrene; Triphenyl tetrazolium chloride; e-Plastic