BIOREMEDIATION OF CHEMICAL POLLUTANTS- CONTAMINATED WATER A-BIODECOLORIZATION OF CRYSTAL VIOLET CONTAMINATED WATER BY Pseudomonas geniculata

Abstract

Biodcolorization of crystal violet (C V) was investigated in aquatic system. C V decolorizing bacterium (designated isolate AT 17) was isolated from effluent sample using enrichment technique by clear zone formation. Based on morphological, physiological and 16S rDNA, this bacterium was identified as Pseudomonas geniculata. It was capable of using C V as a sole source of carbon. Nutrient agar medium inhibited C V decolorization but mineral salt medium (MSM) increased C V decolorization. C V decolorizing by P. geniculata was found to be optimum at pH 7 and 35°C. Additional carbon sources (i.e., glucose) and nitrogen sources (i.e., peptone, yeast extract and beef extract) inhibited completely C V decolorization. On the ather hand, ammonium chloride and ammonium sulphate increased the C V decolorization. Ammonium chloride was the best inorganic nitrogen source in C V decolorization. Incubation period for 7 days was the optimum for C V decolorization. P. geniculata was able to decolorize 99% of C V completely in liquid medium at pH 7 and 35 °C after 7 days comparing with uninoculated medium(control). There was no toxicity of detected C V after 7 days of incubation with P. geniculata on Bacillus subtilis as microbial bioassay test. The dissipation of C V was coinciding with increasing P. geniculata biomass in C V contaminated water. This study has shown that P.geniculata C V could be applied to remediate Chemical pollutants - contaminated water.