平菇半纤维素酶酶学性质研究

Study on the Character of Hemicellulase in Pleurotus ostreatus

在平菇产半纤维素酶条件及酶学性质初步研究的基础上,研究了酶的温度稳定性、pH稳定性,无机离子、反应时间对酶活性的影响。该酶底物浓度效应和米氏常数(Km)值测定结果表明,酶液在50℃以下有较好的热稳定性,pH值在4.4～5.4范围内剩余酶活较大,Mn2+、Mg2+对半纤维素酶有激活作用,Cu2+、Zn2+对半纤维素酶有抑制作用,米氏常数为7.39×10-2 g·L-1,最少反应时间为25 min。

Effect of temperature, pH, inorganic ions and reaction time on the enzyme stability was studied on the basis of substrate concentration and enzyme character. The results of the determination of Km showed that the Hemicellulase could work continuously under 50℃ and was stable when pH was from 4.4 to 5.4. Mn^2＋,Mg^2＋ had the activation but Cu^2＋,Zn^2＋ had the inhibition on activity of Hemicellulase. The Km of the Hemicellulase was 7.39×10^-2g.^L^-1. The reaction time was at least 25 minutes.