碱性过氧化氢预处理条件对木薯渣酶解作用效果的研究

Study on Alkaline Hydrogen Peroxide Pretreatment Conditions on the Enzymatic Hydrolysis of Cassava Residue

为了探究不同碱性过氧化氢预处理条件对酶解的作用效果,对于不同预处理条件的木薯渣测定了木素去除率并且进行X-射线双晶衍射。采用Design-Expert.V.8.0.6.1分析软件对碱性过氧化氢预处理过程中的反应温度、反应时间、过氧化氢用量3个因素及各自的3个水平,以酶水解液中还原糖提取率为评价指标,进行实验设计及分析。结果表明:最佳预处理条件为:固液比1:20、反应pH 11.5、反应温度42℃、反应时间274 min、过氧化氢用量5.4%。在此条件下预处理的木薯渣进行酶解,酶解条件为:液比1:30,p H 4.5,纤维素酶用量400 U·g^(-1)(对绝干原料),多糖水解酶用量120 FXUs·g^(-1)(对绝干原料),摇床转速150 r·min^(-1),50℃恒温,酶解时间36 h。酶水解液中还原糖的溶出率最高,为85.93%。木薯渣的结晶指数:最佳预处理条件下,降低了46.51%,双酶解后降低了67.87%。

To study the effects of different alkaline hydrogen peroxide pretreatment conditions on enzyme solution of cassava residue. X-ray double crystal diffraction to get the trend of crystallization index with different pretreatment conditions, Design- Expert.V.8.0.6.1 were used to determine optimize pretreatment conditions and enzymes loadings in the hydrolysis. Alkaline hydrogen peroxide, reaction temperature, reaction time and respective levels. Yield of reducing sugars in hydrolysis as the evaluation index. q-he results showed that, the pretreatment increased cassava residue enzymatic digestibility. In the optimal pretreatment （pH=11.5, solid-to-liquid ratio： 1：20, time： 274min, temperature： 42℃, 5.4% hydrogen peroxide of cassava residue） and hydrolysis conditions （150 r·min-1, pH=4.5, solid-to-liquid ratio： 1：30, time： 36 h, temperature： 50℃,400 U·g-1 cassava residue and 120 FXUs·g-1 cassava residue）, The yield of reducing sugars 85.93% were obtained in hydrolysis. Under optimum pretreatment conditions, crystallization index was reduced by 46.51%, crystallization index was reduced by 67.87% after double enzyme solution.