Abstract: Degradation of acid orange,which is a typical azo dye,is investigated by using laccase extracted from aspergillus oryzae.Influences of reaction time,pH value,adding amount of laccase,temperature,dye concentration on decolorization rate are explored.Besides,the decolorization effects of EDTA,SDS mediator and metal ions are studied.The suitable decolorization conditions for acid orange are found as follows:the reaction time is 50 minutes,pH=6,the enzyme dosage is 2 ml,the reaction temperature is at 50℃,and the initial dye concentration is 0.1 g·L-1.Decoloration rate of acid orange is 88.32% under the most suitable conditions.The effects of metal ions and enzyme inhibitors on the decolorization of acid orange are also studied.It is found SDS can inhibit the catalytic activity of laccase significantly,Fe2+ has a whole inhibition to laccase,and Mg2+ has certain promoting effect on decolorization.
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