Development of low cost upflow column bioreactor for degradation and detoxification of Blue HERD and textile effluent by Lysinibacillus sp. RGS immobilized on Loofa

Abstract

Dyes and other toxic components of textile wastewater create severe hazards to receiving water. In the present study, Lysinibacillus sp. RGS, an effective dye degrading bacteria immobilized on Luffa cylindrica (Loofa) was used to decolorize sulphonated azo dye Blue HERD and 50% real textile effluent in an upflow column bioreactor. Blue HERD (200 mg L−1) and 50% real textile effluent were degraded at volumetric flow rate 40 mL h−1 and 15 mL h−1, respectively. Induction in reductive (NADH–DCIP reductase and azoreductase) as well as oxidative (laccase, tyrosinase and veratryl alcohol oxidase) enzymes proved enzymatic decolorization of Blue HERD and 50% textile effluent. Significant reduction in COD, BOD, TOC, hardness and alkalinity of decolorized samples of Blue HERD and 50% effluent confirmed mineralization. HPTLC, FTIR and GCMS analysis confirmed degradation of Blue HERD into simple intermediates during decolorization in bioreactor. Less toxic nature of metabolites was confirmed using genotoxicity, cytotoxicity and phytotoxicity tests.