Treatment of Textile Dye Wastewater using Cynobacteria Spirulina Sp

Abstract

Along with toxic dyes textile dye wastewater contains various xenobiotic compounds therefore their treatment is necessary before discharging into the environment. Bioremediation was considered as one of the eco-friendly and self-sustainable treatment systems and amongst them cyanobacteria was considered as one of the best resources for the bioremediation of organic pollutants. Thus, in this present study, Spirulina sp. was evaluated for the treatment of real textile dye wastewater (RTDW) along with the removal of metal ions and other organic pollutants. The metabolic activities to Spirulina sp. leads to complete more than 98% decolorization of Reactive Brown GR11, Reactive Magenta HBB 26, Reactive Red Bs11 and Reactive Yellow 160 dye. However, to enhance the treatment efficiency of Spirulina sp. carbon and nitrogen sources were optimized. In the presence of 1% glucose and yeast extract Spirulina sp. showed 86% American Dye Manufacturers’ Institute (ADMI) removal and 83 % chemical oxygen demand (COD) reduction from the undiluted non-sterilize RTDW. The maximum treatment efficiency of Spirulina sp. was observed at pH-7 and 30 °C under optimized co-substrates. Degradation of RTDW and representative four azo dyes were further confirmed by using ultraviolet–visible spectrophotometry (UV–vis), High Performance Liquid Chromatography (HPLC), and Fourier- transform infrared spectroscopy (FTIR) analysis. Additionally, toxicity analysis was considered as the best method to evaluate the efficiency of treatment process. Phytotoxicity and cytotoxicity assay clearly show that Spirulina sp. treatment significantly reduces the toxic characteristics of RTDW.