摘要
木霉经固态发酵制成纤维素酶湿曲 ,按曲水体积比 1∶5加入 4 0℃去离子水 ,保温 6 0min后 ,过滤获得粗纤维素酶液。在酶活为FPase 2 2 6u/mL的稀酶液中 ,加入丹宁至 5 0g/L时 ,粗酶液中纤维素酶接近完全沉淀下来 ,将沉淀分散于 pH4 6的 0 1mol/L柠檬酸缓冲液中 ,加入分子质量为 6 0 0 0u的聚乙二醇 (PEG)至丹宁含量的 1 6～ 4 0倍 ,酶活回收率达到2 10 %～ 2 4 5 % ,可将纤维素酶浓缩 7～ 8倍。PEG对纤维素酶有激活作用 ,采用丹宁作为纤维素酶的沉淀剂 ,PEG可将纤维素酶从酶 丹宁复合物中解析出来。丹宁、PEG的用量与酶液中的蛋白质含量有关 ,PEG超过解析酶用量的一定范围 ,因激合纤维素酶使酶活回收率超过 10 0 % ,过多PEG会使系统发生相改变 ,从而使酶失活 ,使得酶活回收率急剧降低。
Cellulase was extracted from the solid state culture medium in which a strain of Trichoderma was grown. After the culture medium was steeped in 40℃ ion free water for 60?minutes ,the crude cellulase liquid was made by filtering the steeper, when the content of tannin in the enzyme liquid up to 5.0?g/L and the enzyme-tannin compound was dispersed in pH 4.6 citrate buffer, cellulase could be liberated by putting PEG 6000 into the suspension, the enzyme recovery rate reached 245 percentage and the cellulase was concentrated 7～8 times. The experimental results proved that PEG had an activation to cellulase ,if tannin was used as a precipitator during cellulase extraction, PEG could liberate the enzyme from the enzyme-tannin compound .The content needed of tannin and PEG was relative to the protein quantity in the liquor .When the content of PEG exceeded the amount needed to liberate the enzyme, to some extent, the cellulase could be activated. If PEG's amount was too much it would make cellulase inactivated because the system had been changed.
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2001年第8期41-44,共4页
Food and Fermentation Industries
关键词
纤维素酶
丹宁
聚乙二醇
提取法
酶制剂
cellulase, tannin, polyethylene glycol, extraction method
