A Rapid and Simple Method for Screening Microorganisms with a Potential for Catechol Biodegradation

Catechol is a highly toxic compound that is also a key intermediate in biodegradation pathways of various aromatic compounds. In this paper, a new screening method for isolation of microorganisms with the potential for catechol biodegradation is reported. The method described is based on the ability of catechol to form a color complex with Fe3+ ions. For this purpose, basal medium that is widely used for classification of microorganisms by carbon requirements was used. Specifically, minimal Bushnell Haas medium plates supplemented with catechol at 500 mg l−1 concentration were used for both yeast and bacteria cultivation. After appearance of microorganism colonies on the growth medium, each plate was flooded with 7.0 ml of 5% (w/v) of FeCl3 and incubated for a period of 5 min at room temperature. Flooding with this solution led to the formation of a green color from Fe3+-catechol complexes in the growth medium and an appearance of clear zones around colonies of microorganisms that utilize catechol as a sole source of carbon. Based on this, the presented method could be useful as a screening step for microorganisms with a potential for catechol biodegradation.