[Decolorization of synthetic dyes with a new isolated yeast Candida krusei]

A new yeast isolate Y-G-1, identified as Candida krusei, capable of degrading Reactive Brilliant Red K-2BP, was obtained from soil by screening experiments. This strain gave a maximal decolorization (99%) for Reactive Brilliant Red K-2BP (200 mg/L) after incubation of 12 h. In order to get this decolorization effect, the optimal inoculation volume of Candida krusei was not less than 5%, the optimal pH of culture medium was within a range from 4 to 9, and the concentrations of (NH4)2SO4 and glucose were not lower than 0.1% and 0.5%, respectively. The research results on the mechanism of decolorization show that Candida krusei could biodegrade Reactive Brilliant Red K-2BP. In addition, Candida krusei could also decolorize 62% - 96% of another 9 dyes (50mg/ L). Specially for azo dyes, including Weak Acid Brilliant Red B, Reactive Black KN-B and Reactive Red M-3BE, their decolorization rates were over 90 %, and for triphenylmethane dye, Mordant Blue B, it was up to 93%. All these results indicate that this strain have potential application in dye wastewater treatment.