Treatment of Pulp and Paper Mill Effluent by 4-Chlorosalicylic Acid-degrading Microbial Community for Analysis of Toxicity of Seedlings

Abstract

A microbial community utilizing 4-chlorosalicylic acid as sole source of carbon and energy was enriched in the chemostat. The bacterial community contained four different isolates characterized on the basis of morphological properties

of the colonies. The isolates were identified as <i>Klebsiella </i>sp. (one isolate) and <i>Pseudomonas </i>sp. (three isolates). The bacterial community was applied for the treatment of pulp and paper mill effluent in fixed film bioreaetor containing soil, sand, and gravel at the bottom of the reactor for immobilization of bacterial biomass. The community exhibited significant reduction in colour (80 per cent), phenol (67 per cent), Chemical Oxygen Demand (COD) (70 percent) and lignin content (41 per cent) after treatment of 15d. The effluent treated by microbial community was applied for the germination of seeds of paddy and

wheat and growth of seedling, exhibited significant reduction in toxicity of contaminant present in effluent.