Effect of physicochemical conditions on phenol degradation by Corynebacterium glutamicum: A focus on phenol catabolic enzymes

The present study was aimed to investigate phenol catabolic activity and phenol tolerance ability of lysine producing bacterium, Corynebacterium glutamicum ATCC 13032. The results revealed that phenol inhibited the growth rate of bacteria (< 20%) at a concentration of >1500 ppm, indicating the toxicity of phenol to bacterial cells at higher concentrations. The maximum (> 95%) growth rate was observed at 200 ppm during a period of 24 h. In the present study, optimal conditions were standardized at different concentrations of phenol to know the phenol catabolism and phenol tolerance of C. glutamicum. Further, an attempt was also made to know the effect of yeast extract on phenol degradation by C. glutamicum. The results also demonstrated that increase in the yeast extract enhanced phenol (300 ppm) degradation efficiency of C. glutamicum, which reflects the phenol tolerance of bacteria. Thus, in-depth optimization studies on metabolic and molecular aspects may contribute to understand the potentiality of C. glutamicum in the biodegradation of phenol in large scale bio-remediation processes.