REMOVAL OF PHENOLIC COMPOUNDS FROM WASTEWATER USING MUTANT STRAIN OF PSEUDOMONAS PICTORUM

Accumulation of alien chemicals which cannot be assimilated creates toxicity both for those flora and fauna and for humans who eat fish which feed on them. Phenol is one such chemical that causes alarm by this process of accumulation. The difficulty with the treatment of phenol is that it can inhibit microbial growth at relatively low concentrations of 200 mg/l. Hence, removal of phenol from industrial aqueous effluents is an important practical problem. A mutant strain of Pseudomonas pictorum was isolated after extensive screening and the necessary cultural parameters were studied. The results indicated that the selected mutant strain, designated as MU 174, could degrade 2.0g/l phenol in about 33h at a pH and temperature of 7-9 and 30-34°C, respectively. More than 0.05% glucose showed a repressive effect. In addition to the degradation of phenol, it could degrade resorcinol, 2- and 4-chlorophenol. MU 174 was effective in treating phenolic wastewater in the presence of sewage medium.