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J Ind Microbiol Biotechnol (2008) 35:13531357 DOI 10.1007/s10295-008-0435-5
ORIGINAL PAPER
Decolorization of textile dye by Candida albicans isolated from industrial efuents
Vivian Vitor Carlos Renato Corso
Received: 20 March 2008 / Accepted: 30 July 2008 / Published online: 20 August 2008 Society for Industrial Microbiology 2008
Abstract The aim of the present work was to observe microbial decolorization and biodegradation of the Direct Violet 51 azo dye by Candida albicans isolated from industrial efuents and study the metabolites formed after degradation. C. albicans was used in the removal of the dye in order to further biosorption and biodegradation at different pH values in aqueous solutions. A comparative study of biodegradation analysis was carried out using UVvis and FTIR spectroscopy, which revealed signicant changes in peak positions when compared to the dye spectrum. Theses changes in dye structure appeared after 72 h at pH2.50; after 240 h at pH 4.50; and after 280 h at pH 6.50, indicating the different by-products formed during the biodegradation process. Hence, the yeast C. albicans was able to remove the color substance, demonstrating a potential enzymatic capacity to modify the chemical structure of pigments found in industrial efuents.
Keywords Textile dyes Biodegradation
Decolorization Candida albicans Direct Violet 51
Biosorption
Introduction
Dyes and dyestuff are used in textile, pharmaceutical, leather and cosmetic industries. The main use occurs in textile manufacturing, resulting in wastewater that contains
a variety of these pollutants. The release of dyes is a cause of concern due to the effects on the environment and human health [13]. A number of these dyes are very stable in the presence of light, water and chemicals. Degradation is used in the bioremediation of these dyes and is an attractive solution due to its lower cost and environmentally friendlier technology when compared to chemical and physical treatment processes [14].
The annual world production of dyestuff amounts to more than 7 9 105 tons [17]. It is estimated that 1015% of the total production of colorants is lost during synthesis and dyeing processes [5]. Pigmented industrial efuent is the most obvious indicator of water pollution. The discharge of highly pigmented synthetic dye is not only aesthetically unpleasing, but causes considerable harmful effects when released in bodies of water. Some methods try to solve...