Statistical Assessment of Phenol Biodegradation by a Metal-Tolerant Binary Consortium of Indigenous Antarctic Bacteria

Abstract

Since the heroic age of Antarctic exploration, the continent has been pressurized by multiple anthropogenic activities, today including research and tourism, which have led to the emergence of phenol pollution. Natural attenuation rates are very slow in this region due to the harsh environmental conditions; hence, biodegradation of phenol using native bacterial strains is recognized as a sustainable remediation approach. The aim of this study was to analyze the effectiveness of phenol degradation by a binary consortium of Antarctic soil bacteria, Arthrobacter sp. strain AQ5-06, and Arthrobacter sp. strain AQ5-15. Phenol degradation by this co-culture was statistically optimized using response surface methodology (RSM) and tolerance of exposure to different heavy metals was investigated under optimized conditions. Analysis of variance of central composite design (CCD) identified temperature as the most significant factor that affects phenol degradation by this consortium, with the optimum temperature ranging from 12.50 to 13.75 °C. This co-culture was able to degrade up to 1.7 g/L of phenol within seven days and tolerated phenol concentration as high as 1.9 g/L. Investigation of heavy metal tolerance revealed phenol biodegradation by this co-culture was completed in the presence of arsenic (As), aluminum (Al), copper (Cu), zinc (Zn), lead (Pb), cobalt (Co), chromium (Cr), and nickel (Ni) at concentrations of 1.0 ppm, but was inhibited by cadmium (Cd), silver (Ag), and mercury (Hg).

A study of highly efficient phenol biodegradation by a versatile Bacillus cereus ZWB3 on aerobic condition

“…The presence of Mn 2þ and Zn 2þ delayed the degradation of phenol, which could still be completely degraded within 24 h and 72 h, respectively. However, the presence of Cu 2þ , Cd 2þ and Hg 2þ completely inhibited the degradation of phenol, because the accumulation of these metal ions in cells inhibited the activity of catechol dioxygenase and thus inhibited the degradation of phenol (Subramaniam et al 2021). The tolerance concentrations of ZWB3 on the stress of Mn 2þ and Zn 2þ were higher than those of Glutamicibacter nicotianae MSSRFPD3 and Cobetia sp.…”