Biodegradation of Malachite green by Kocuria rosea MTCC 1532

Ganesh Parshetti, Satish Kalme, Ganesh Saratale, and Sanjay Govindwar*

Department of Biochemistry, Shivaji University, Kolhapur-416004, India

Malachite green (50 mg/L) was completely decolorized under static anoxic condition within 5 h by bacteria Kocuria rosea MTCC 1532; however decolorization was not observed at shaking condition. K. rosea have also shown decolorization of azo, triphenylmethane and industrial dyes (cotton blue, methyl orange, reactive blue 25, direct blue-6, reactive yellow 81, and red HE4B). Semi-synthetic media containing molasses, urea and sucrose have shown 100, 91, 81% decolorization respectively. Induction in the activities of malachite green reductase and DCIP reductase was observed during MG decolorization suggesting their involvement in the decolorization process. UV-Visible absorption spectrum, HPLC and FTIR analysis showed degradation of MG. Toxicity study revealed the degradation of MG into non-toxic products by K. rosea.

Keywords: decolorization, K. rosea, malachite green reductase, HPLC, toxicity.