Integrated Kinetic and Transcriptomic Insights Into Nano-Assisted Tandemol Biodegradation by UV-Mutagenized...

This study assesses the kinetics of Tandemol lubricant degradation by Pseudomonas synaxantha rhizo-25 after UV treatment and nanoparticle inclusion. The degradation efficiency was assessed in terms of the Total Petroleum Hydrocarbons (TPH) and aromatic compounds degraded in a liquid medium containing Tandemol lubricant. The medium composition was further supplemented with nanoparticles to evaluate their impact on the process. Metabolite profiling was conducted using Gas Chromatography-Mass Spectrometry (GC-MS), while transcriptomic analysis identified key enzymes involved in the degradation process. For TPH degradation, biodegradation rate (K) and half-life (t_1/2) values were found to be -0.39 M^-1day^-1 and 10.22 days (wildtype), and 0.013 M day^-1 and 9.33 days (UV-treated), respectively. For the aromatic compounds, the estimated K and t_1/2 values were -63.30 M^-1 day^-1 and 7 h (wildtype), and -0.69 day^-1 and 1.01 days (UV-treated). The nanoparticle supplemented aromatic degradation yielded K and t_1/2 values of -21.01 M^-1h^-1 and 0.85 h (UV-treated). Aromatic compound degradation was observed to follow the meta-cleavage pathway with terminal oxidation as an activation mechanism. Oxidoreductases, namely Cytochrome P450 and Tau D/Tfd A dioxygenase, were responsible for the primary step in the degradation pathway. Overall, these results showed that the UV treatment and the inclusion of nanoparticles enhanced biodegradation efficiency towards optimum petroleum contaminant bioremediation.