Guar gum blended alginate/agarose hydrogel as a promising support for the entrapment of peroxidase: Stability and reusability studies for the treatment of textile effluent.

Ginger peroxidase (GP) was entrapped into the hydrogels of guar gum (GG)-alginate/agarose and these immobilized GP preparations were employed for the treatment of textile effluent. GG is a natural hydrophilic polysaccharide, the average size of which increases in its hydrated form that helps in retaining the enzyme inside the entrapping support. Therefore, the activity retention by alginate-guar gum (ANGG) and agarose-guar gum (AGG) was higher than that of alginate and agarose alone. ANGG-GP and AGG-GP were highly stable against various physical and chemical denaturants during the decolorization of textile effluent. As compared to free GP, both the immobilized preparations were more efficient in the decolorization of textile effluent in batch processes. After 10th repeated use in batch processes, ANGG-GP and AGG-GP was quite effective in removing up to 68% and 55% of the color from textile effluent, respectively. Continuous packed bed reactors containing ANGG-GP and AGG-GP were able to decolorize around 80% and 69% of the effluent color, respectively, even after 30 days of their continuous operation at room temperature (30 °C). Genotoxicity of textile effluent was significantly reduced after GP mediated decolorization.