重组过氧化物酶A4-Prx酶学特性及其降解DDGS中ZEN的研究

Study on characterization of a recombinant peroxidase A4-Prx and its ZEN detoxification in DDGS

摘要: 初步研究了一种重组过氧化物酶Acinetobacter sp.SM04（A4-Prx）的酶学特性,并先对pH、温度和H2O2浓度对过氧化物酶A4-Prx活性的影响进行单因素优化,然后采用正交实验设计对A4-Prx降解玉米酒糟中玉米赤霉烯酮的反应条件进行了优化。结果表明,重组过氧化物酶A4-Prx不含有血红素,其过氧化物酶活性的最适pH、温度和H2O2浓度分别为pH8.5、75℃、25mmol/L;A4-Prx降解DDGS中ZEN的最佳反应条件为:H2O2浓度40mmol/L,料液比1:2（g/mL）,温度70℃,时间9h,且在该条件下ZEN降解率为99.2%±0.2%。

Abstract: The enzymatic characteristics of the recombinant peroxidase Acinetobacter sp.SM04 (A4-Prx) was studied.Firstly, the effect of pH, temperature and H2O2 concentration on peroxidase A4-Prx activity were studied.Then, the orthogonal experiment was designed to receive the optimal ZEN (zearalenone) degradation rate of A4-Prx in DDGS (dried distillers' grains and soluble) .The A4-Prx characterization result showed that it was an alkaline and protoheme independent peroxidase, and the optimal pH value, temperature and H2O2 concentration for peroxidase A4-Prx activity were pH8.5, 75℃ and 25mmol/L respectively.And the optimum condition for ZEN decontamination were as follows:40mmol/L H2O2, 9h, 70℃ and 1∶2 (solid-liquid ratio, g/mL) .Under the optimum condition, ZEN degradation rate was 99.2%±0.2%.