Biodegradation potential of phenol by pure and defined mixed cold-adapted bacterial consortia from Antarctica

• Main Author: Subramaniam, Kavilasni
• Format: Thesis
• Language: English
• Published: 2021
• Subjects: Biodegradation; Phenol > Environmental aspects - Antarctica; Antarctic; King George Island; South Shetland Islands; The Antarctic; Antarc*; Antarctica
• Online Access: http://psasir.upm.edu.my/id/eprint/104577/; http://psasir.upm.edu.my/id/eprint/104577/1/FBSB%202022%201%20IR.pdf

The risk of phenol pollution from daily waste discharge and accidental oil spillage is ever-present due to increasing activities in the Antarctic continent, mainly related to the supply and operation of research stations and field expeditions, tourism, marine and air transportation. Increased levels of phenol concentration in the Antarctic environment bring significant risk to both aquatic and terrestrial biota due to its highly toxic properties and persistence. Sustainable human presence and activity in Antarctica require effective remediation technologies to be developed and their rapid application when required. The main purpose of the present study was to isolate new taxa of pure phenol-degrading bacteria from Antarctic soil and, both as a pure isolate and together with previously isolated phenol-degrading bacteria as a consortium, will be capable of rapid degradation of phenol at low temperatures (0-15°C). In addition, this study also focuses on identification of phenol-degrading pathway(s) of the pure culture, conventional and statistical optimisations of phenol degradation by both pure and mixed cultures, and the effect of heavy metals on phenol degradation by pure and mixed cultures. This thesis reports the isolation of a potential phenol-degrading bacterial strain (AQ5-15) from soil from King George Island, South Shetland Islands, Antarctica. This strain was identified as a member of the genus Arthrobacter based on 16S rRNA gene sequence analysis. Based on whole arest identified relative was suggested to be Paeniglutamicibacter sulfureus (99.38% similarity). Preliminary screening showed that strain AQ5-15 was capable of completely degrading 0.5 g/L phenol within 108 h at 10°C and it was selected for a detailed study. The genomic analysis identified the presence of genes encoding a complete pathway of aromatic compound metabolism in strain AQ5-15, consistent with the ability of the strain to utilise phenol as the sole carbon source. The genomic analysis was validated using enzyme assays of catechol ...