【摘要】 利用海藻酸钙凝胶包埋法制备固定化细胞黄绿木霉,结果表明:海藻酸钠质量浓度50 g/L,培养基初始pH值4.0~4.5,以滤纸浆为培养基碳源培养的小球的稳定性好。发酵产酶培养时以滤纸浆为碳源,海藻酸钠质量浓度为50 g/L,CaC l2质量浓度控制在20 g/L,培养基初始pH值选择为4.5,产酶效果好、酶活力高、保持时间长。添加表面活性剂Tw in-80后,产酶能力可进一步提高。通过(NH4)2SO4分级沉淀、Sephadex G-100分子筛层析和DEAE Sephadex A-50离子交换层析等步骤,分离纯化出黄绿木霉纤维素酶系中达到电泳纯的3种内切葡聚糖酶(EGⅠ、EGⅡ、EGⅢ)和2种β-葡萄糖苷酶(BGⅠ、BGⅡ)。通过SDS-PAGE和IEF电泳测得5个酶组分的相对分子质量(Mr)分别为62 300、71 900、52 600、85 300和78 300,等电点分别为5.4、4.8、5.0、5.6和5.8。更多还原

【Abstract】 Immobilized cells were prepared through embedment of Trichoderma aureoviride with calcium alginate.The suitable culture conditions were sodium alginate（50g/L）,initial pH value of the substrate 4.0[KG-*2]-4.5 and using filter paper pulp as（carbon） source of the substrate.The enzymatic activity of the immobilized cells was improved when concentration of calcium dichloride was（20g/L）,initial pH value of the substrate was 4.5,concentration of sodium alginate was（50g/L） using filter paper pulp as（carbon） source of the substrate.Addition of the surfactant Twin-80 could further increase enzymatic activity.Three endoglucanases and two β-glucosidases from the fungi were separated and purified to electrophoretic homogeneity through processes of（NH₄）₂SO₄ fractional precipitation,Sephadex G-100 gel chromatography and DEAE Sephadex A-50 ion exchange chromatography.They were designated as EGⅠ,EGⅡ,EGⅢ,BGⅠ and BGⅡ,with relative molecular weights（M_r）of 62 300,71 900,52 600,（85 300） and 78 300 by SDS-PAGE,and isoelectric points of 5.4,4.8,5.0,5.6 and 5.8,respectively.更多还原