作　　者： ; ; ; ; ;

机构地区： 华南理工大学生物科学与工程学院

出　　处： 《食品与发酵工业》 2006年第8期1-4,共4页

摘　　要： 由1株分离、纯化自曲精的酱油曲霉的分生孢子制备原生质体,并进行紫外诱变,得到7株中性蛋白酶活提高幅度较大的紫外突变株U系,中性蛋白酶活最高的1株达到6 197.4U,为出发株的1.94倍。对原生质体制备条件进行了优化:选取孢子生长旺盛的新鲜斜面培养物(培养5 d左右)制备孢子悬浮液;采用25 mmol/L-巯基乙醇+5 mmol/L Na2EDTA体系预处理20 min;酶解条件是:1%溶菌酶+1%蜗牛酶+1%纤维素酶,山梨醇作为渗透压稳定剂(0.6 mol/L,pH6.88),酶解温度33℃,酶解5 h;再生培养基为0.6 mol/L NaCl高渗透压豆汁培养基,涂布法再生。 Protoplasts were prepared from spores of an Aspergillus sojae and treated by UV. Seven strains with improved neutral protease activity were obtained, of which the highest protease activity is 6 197.4U, about 1.94 times of its parent. A series of optimum data for preparing protoplast from Aspergillus sojae spore were obtained： The strain was incubated on slant for the preparation of spore suspension until the green spore was in full bloom （about 5 days）. The spore suspension were pretreated in the system （25mmol/L β- mercaptoethanol ＋ 5 mmol/L EDTA） for 20 min. Enzymatic digestion was optimized with： 1% lysozyme ＋ 1% snailase＋ 1% novozyme188, 0.6mmol/L sorbitol citrate buffer （pH6.88）. The digestion system was incubated at 33℃ for 5 hours and 0.6mmol/L NaCl was used as the osmotic stabilizer in the regeneration medium for protoplast regeneration.

关 键 词： 酱油曲霉 中性蛋白酶活 分生孢子 原生质体 紫外诱变

领　　域： [化学工程]