Aureobasidium pullulans UVMU3-1产耐热性胞外漆酶活性物质培养基优化及其对染料脱色作用  

Optimization of culture conditions for thermostable extracellular laccase activity of Aureobasidium pullulans UVMU3-1 and its performance in dye decolorization

作　　者：孔丽[1] 米晓春[2] 耿圆圆[1] 林超[1] 王金鹏[1] 李利[2] 李炳学[2] 张宁[1] 

机构地区：[1]沈阳农业大学生物科学技术学院,沈阳110866 [2]沈阳农业大学土地与环境学院土肥资源高效利用国家工程实验室,沈阳110866

出　　处：《环境科学学报》2015年第12期3824-3831,共8页Acta Scientiae Circumstantiae

基　　金：国家自然科学基金(No.31271818);中国博士后科学基金(No.2012M510837);沈阳市科技创新专项(No.F13-143-3-00)~~

摘　　要：对出芽短梗霉无色素突变株Aureobasidium pullulans UVMU3-1产耐热性胞外漆酶活性物质培养基进行优化,并研究其分子量大小、热稳定性及对三苯甲烷类染料孔雀石绿和结晶紫的脱色作用.结果表明:蔗糖、NaNO_3为UVMU3-1产耐热性胞外漆酶活性物质的最佳碳源和氮源,产酶优化培养基配方为:蔗糖66.5 g·L^(-1),NaNO_338.4 g·L^(-1),NaCl 1.08 g·L^(-1),酵母浸粉0.2 g·L^(-1),KH_2PO_41 g·L^(-1),pH=6.0.影响UVMU3-1产耐热性胞外漆酶活性物质的因素依次为:起始pH>蔗糖>NaCl>NaNO_3,培养7 d时产生最大酶活(94.81 U·L^(-1)),比对照提高3.85倍.其分子量小于1000 D,具有良好的热稳定性,煮沸30 min后高温酶活仍残留72.50%.粗酶液(7.5 U·L^(-1))与三苯甲烷类代表性染料孔雀石绿和结晶紫75℃反应5 min后,脱色率分别为76.3%、77.5%,反应35 min后脱色率分别达到96.3%、95.3%.A pigment free mutant Aureobasidium puUulans UVMU3-1, with thermostable extracellular laccase activity, was gained by UV mutagenesis. Then, the production conditions of the substance with laccase activity from UVMU3-1, molecular weight, thermal stability and its decoloration ability for malachite green and crystal violet were investigated. The results showed that sucrose and NaNO3 were the best carbon and nitrogen sources for the production of thermostable extracellular laccase activity substance from UVMU3-1, respectively. The most optimized medium condition was found as sucrose 66.5 g.L-1 , NaNO3 38.4 g. L-1 , NaCI 1.08 g. L-1 , yeast extract 0.2 g- L-1 , KH2 PO4 1 g. L-1 , with initial pH = 6.0. Four factors significantly impacted UVMU3-1 laccase activity as the order of initial pH〉sucrose〉NaCl〉NaNO3. Maximal laccase activity （94.81 U.L-1） of UVMU3-1 was gained at 7 d, and 3.85 times higher than that in the original YND medium. Its molecular weight was less than 1000 D. The high-temperature laccase activity was still remained 72.50% after boiled for 30 minutes. The heat-resistant laccase from UVMU3-1 （7.5 U. L-1 , ） was used to decolorize triphenylmethane dyes. The decolorization rate reached 76.3% for malachite green and 77.5% for crystal violet after high-temperature bleaching 5 min at 75℃, respectively. After bleaching for 35 min at 75℃ , the decolorization rate reached to 96.3% for malachite green and 95.3% for crystal violet, respectively.

关 键 词：出芽短梗霉 漆酶活性物质 耐热性 染料脱色 

分 类 号：X172[环境科学与工程—环境科学]