REMEDIATION OF TEXTILE DYES (DIRECT RED AND ACID ORANGE) BY FRESHWATER CYANOBACTERIA

Abstract

Textile dyes represent a large group of organic substances that impose undesirable effects on the environment. An emerging ecological concern is the effluents from the textile industry and the dyeing-related processes that were not conveniently treated before they are introduced into the natural environment reaching reservoirs and water bodies. However, depending on the dye type and the application, the final stage of the dye can significantly contribute to the release of waste of several chemical substances with variable composition. Cyanobacteria have a wide and varied impact on natural ecosystems and can act causing beneficial or noxious effects to the health of humans and animals. Compared with some physical, chemical treatment the biological treatment has high significance due to its cost effectiveness and eco-friendliness (Thajuddin, 2005; Singh et al., 1969). Among this the marine Cyanobacteria have a unique function system in the removal of colours from textiles. The present study details with the decolourisation of textile dyes (Direct red and Acid Orange) by freshwater Cyanobacteria. Maximum decolourisation takes place in case of direct red dye compared to acid orange dye at different concentration and conditions. Microscopic and viability studies were performed along with the effect of respective dyes on the pigments of Cyanobacteria was studied. Decolourisation rate of both the dyes increased upon treatment with starch and sodium chloride. Hence the given study showed that freshwater Cyanobacteria is an effective, economical alternative for the degradation of the respective textile dyes.