Dyes are substances used to impart color to fabric, food and other objects. Synthetic dyes are used extensively for textile dyeing and as additives in petroleum products. The textile dyeing process requires a large volume of fresh water with fairly high purity and discharges equally large volume of wastewater after dyeing process. In this work, the fungus Pleurotus florida isolated from Western Ghats was grown on potato dextrose broth exhibited laccase activity together with lignin peroxidase (0.10 U g-1) and Manganese peroxidase (0.6 U g-1) activity. The maximum amount of laccase produced was approximately 4.8 U g-1 after 8 days of fermentation using 4-week old inoculum. Bacillus subtilis, were obtained from Tamil Nadu agricultural university, Coimbatore. The spore suspensions of Bacillus subtilis Cot A was used and it exhibited laccase like activity. The reactive dyes selected in this work are reactive yellow, blue, green, purple and red. The paper effluent were collected from Seshasayee paperboard, Erode, Tamil Nadu, India and the textile effluent were collected from Together textile mills, Coimbatore, Tamil Nadu, India. It was found that, out of five reactive dyes, a maximum decolorization was observed on reactive yellow (90%), reactive green (90%) and reactive blue (86%) using consortium of Pleurotus florida crude extracts and Bacillus subtilis CotA spore suspensions instead of Pleurotus florida extract alone. In case of Paper and textile effluents 90% decolorization was achieved in the first day using Pleurotus florida crude extracts and Bacillus subtilis CotA spore suspensions. This study provides evidence that the enzyme obtained from the white rot fungi Pleurotus florida could remarkably help in the dye degradation of textile effluent. This is an eco-friendly, cost effective technology worth consideration by textile manufacturers
Keywords: Decolorization, dyestuff, effluents, laccase, tyrosinase, White-rot fungus
About the Authors:
The authors S Shanmugam, Sathish Kumar T. and Rajasekaran P. are associated with Department of Biotechnology , Kumaraguru college of Technology , Coimbatore, Tamil Nadu, India and Palvannan. T is from Institute of Botany and Microbiology Department of Biology Katholieke Universiteit Leuven and Department of Molecular Microbiology, VIB Kasteelpark Arenberg 31, Belgium.