title: Synergistic growth of Bacillus and Pseudomonas and its degradation potential on pretreated polypropylene.
abstract: This study investigated biodegradation of physically pretreated polypropylene (PP) by using two different combinations of microorganisms, namely, Bacillus flexus + Pseudomonas azotoformans(B1) and B. flexus + B. subtilis(B2), for a period of 12 months. The growth rate of (B1) was found to be high throughout the study period, and reached a maximum of 1 × 10(14) colony-forming units (CFU)/mL. At the end of the experiment, the polymers become hydrophilic. Carbonyl indices showed that ultraviolet (UV)-treated polymers started degrading faster than the thermally treated PP. The thermogravimetric analysis also revealed that UV-treated PP exposed to the B. flexus + P. azotoformans combination for 1 year exhibited maximum degradation (22.7%). The gravimetric weight loss method showed 1.95% weight loss followed by 1.45% with B. flexus + B. subtilis. The changes in the carbonyl indices of the polymer through Fourier-transform infrared (FTIR) analysis also support the degradation.
authors.affiliation: a Department of Biotechnology , Indian Institute of Technology Madras , Chennai , India.|b College of Veterinary Medicine , Biosafety Research Institute, Chonbuk National University , Jeollabuk-Do , South Korea.
authors.forename: Adithan
authors.initials: A
authors.lastname: Aravinthan
authors.affiliation: a Department of Biotechnology , Indian Institute of Technology Madras , Chennai , India.
authors.forename: Ambika
authors.initials: A
authors.lastname: Arkatkar
authors.affiliation: c National Environmental Engineering Research Institute , Nehru Marg , Nagpur , India.
authors.forename: Asha A
authors.initials: AA
authors.lastname: Juwarkar
authors.affiliation: a Department of Biotechnology , Indian Institute of Technology Madras , Chennai , India.
authors.forename: Mukesh
authors.initials: M
authors.lastname: Doble
mesh_terms: D001407:Bacillus / Q000254:growth & development* / Q000378:metabolism*; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development; D057927:Hydrophobic and Hydrophilic Interactions; D011126:Polypropylenes / Q000737:chemistry / Q000378:metabolism*; D011549:Pseudomonas / Q000254:growth & development* / Q000378:metabolism*; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014466:Ultraviolet Rays
chemical_list: D011126:Polypropylenes
keywords: Biofilm; CLSM; FTIR; P. azotoformans; TGA; polypropylene