Biodegradation of phenol using bacteria from different brackishwater habitats

Abstract

Bacterial degradation of phenol (100 to 800 ppm) was studied. It was observed that bacterial diversity and the rate of phenol biodegradation were influenced by the phenol concentrations in the medium. The rate of biodegradation was reduced at higher concentrations of phenolⁱ and <i>Pseudomonas </i>spp and <i>Vibrio </i>spp were mainly involved in the process. The distribution of bacterial genera in the medium was dependent on the compound and its concentration. <i>Pseudomonas </i>and <i>Vibrio </i>were present in all concentrations of phenol, o-cresol and orcinol. Whereas, <i>Bacillus </i>and <i>Alcaligenes </i>could tolerate only up to 200 ppm of these compounds in the medium. <i>Flavobacterium </i>was absent in o-cresol, while it could tolerate 500 ppm of orcinol and 200 ppm of phenol. <i>Cytophaga </i>tolerated 300 ppm of orcinol, and 100 ppm of phenol and o-cresol.

From the present study, it is concluded that in case of an accidental spill of these phenolic compounds many naturally present bacteria could be of great help in their biodegradation and purification of the system thereafter.