Light-emitting diode effect on bacterial decolorization of azo dye

The aim of this study is to examine the influence of Light-emitting diode (LED) on the decolorization of azo dyes. A Tsukamurella sp. J8025 with the best capability of removing the methyl orange was cultivated in static condition. Yeast extract-Malt Extract (YEME) was used in this study. White LEDs was used as light source in this study. The decolorization rate was determined by measuring the absorbance at 485 nm wavelength. The experimental results proved the decolorization efficiency by using J8025 strain cultivated in YEME medium under white and blue LED at 30°C was up from 1.3 to 1.5 fold compared to the control without lighting. In addition, the decolorization rate could be promoted in YMEM medium with 1% of NaCl concentration. The possible reason for the ion effect caused from NaCl could reduce the solubility of azo dyes and increase the chance of strain J8025 contacting the dyes.