Jishna T., Shimna U., Shana, Shainy N.K. and Kunhi. A. A. M. 2016. Isolation and Characterization of 2,3- and 2,6-xylenol-degrading bacterium from petroleum contaminated soil. BIOSPARK’16, National Symposium on ‘Nanotechnology Meets Microbiology’, Dept. of Microbiology, EMEA College of Arts & Science, Kondotty, Malappuram, Kerala. 17-18, Feb. 2016.


Phenol and its derivatives contribute a remarkable bulk to the environmental pollutants a component of effluents from various industries. They are toxic to animals, plants and humans and need to be eliminated from the environment. It can be removed by solvent extraction, adsorption, chemical oxidation, incineration and other non-biological treatment methods but these methods suffer from serious drawbacks such as high cost and formation of hazardous by products. Biodegradation is the breakdown of complex and possibly toxic organic contaminants to non-toxic and simpler elements by microbial activity. Microorganisms have the capability of degrading all naturally occurring compounds. These contaminants can be considered as the microbial food source or substrate. Biodegradation of any organic compound can be thought of as a series of biological degradation steps ultimately results in the oxidation of the parent compound that often results in the generation of energy.

Present study aims to isolate dimethylated phenols (2,3-Xylenol and 2,6-xylenol) degrading microorganism from petrol containing soil. Soil samples from various contaminated areas were collected and a mineral salt medium containing the substrates was inoculated with these soil samples. The organisms capable of growing in these medium which could grow was isolated. The growth of the organism was acclimatized from 500 ppm to 1100 ppm of substrate. The organisms that can grow at 1100 ppm concentration were isolated by spread plate method using mineral salt agar medium. The organism is identified by the biochemical tests. The utilization of the substrate and the increase in the biomass of the organism was estimated which proved the utilization of the substrate by the isolated organism.