Decolorization of Azo Synthetic Textile Dye by Halotolerant Bacteria And Identification Used By 16S rRNA

Abstract

Textile dye has been used in textile industry to produce carpet, batik, cosmetics as well as pharmaceutical products. Utilizing of textile dye especially azo dye in textile industries is more efficient than natural dye. The high production of textile increases liquid wastes. If the liquid waste is not treated properly and discharged directly to environment, it causes pollution that could harm both organism and the environment itself. Azo textile dye is difficult to be degraded in the naturally environment. The aim of this research is to study the potency of halotolerant bacteria to decolorize azo textile dye. The isolates were isolated from the sea around of Mursala Island, Tapian Nauli village, Central Tapanuli district. In this research, the highest percentage of decolorization was shown by 2 isolates, DH2 and DH3. The quantitative decolorization test was performed in MSM liquid media which were amended by three different pH variations: 6, 7 and 8; Three different azo concentrations which were: 600, 800 dan 1000 ppm and three different salinity of media which were: 0 %, 5%, and 10%. The optimum conditions for isolate to degrade azo dye were shown by isolate DH2 at pH 6, salinity 5% and azo concentration of 600 ppm which was 49.64%. Based on 16S rRNA gene, it was known that DH2 was identified to close to Stenotrophomonas pavanii strain LMG 25348 with homology of 97%.