摘要
克鲁维酵母（Ｋｌｕｖｅｒｏｍｙｃｅｓｓｐ．）Ｙ－８５在菊粉提取液培养基中生长产菊粉酶，其细胞和胞外的菊粉酶活力分别约占菊粉酶总活力的７６％和２４％．试验中以酶发酵液作酶液．该酶的Ｓ／Ｉ值为１５．２．酶液在５０，５５和６０℃下保温１ｈ，活力分别残留１００％，９６％和６５％；在８℃下放置７ｄ，１４ｄ，酶活力分别残留９８％和９６％．在ｐＨ３．６～７．０内，酶活性十分稳定．５ｍｍｏｌＬ－半胱氨酸和Ｆｅ＋２分别可使酶活力提高１０．４％和４１．２％．ｙ－８５菊粉酶水解菊粉的适宜条件是：底物为总糖浓度１０％～１５％菊粉提取液，ｐＨ５．０，温度为５５℃，酶用量为底物每克糖加酶８００ｕ（以蔗糖为底物测酶活力）或２６．３ｕ（以菊糖为底物测酶活力）、搅拌酶解６ｈ．在上述条件上，底物降解率最高可达９８．５％．酶解液中，果糖占总还原糖量的８５％．用１１００Ｌ罐进行酶解中试，５批试验，底物降解率平均达９４．２％．
When growing in medium containing inulin in Jerusalem artichoke extracted juice, Kluyveromyces sp. Y-85 synthesized inulinase. About 76% of the total inulinase activity was associated with whole cells, 24% to be secreted into the culture fluid. Therefore the cultures of strain Y-85 was used as the crude enzyme preparation. The activity ratio of the inulinase toward sucrose and inulin was 15. 2. The activity of inulinase remained 100%, 96%and 65% after incubation at 50℃,55℃ and 60℃ for 1 h,respectively. 98% and 96% of the enzymatic activity was observed upon storage at 8℃ for 7 days and 14 days,respectively. The enzymatic actvity was very stable within the pH range of 3. 6～7. 0. Addition of 5 mmol L-cysteine or Fe2+ increased its activity by 10. 4% and 41. 2%, respectively. The suitable conditions of enzymolysis was as following: Jerusalem artichoke extracted juice with 10% ～15% of the total sugar as the substrate, 800 units (the activity unit using sucrose as subtrate) or 26. 3 units (the activity unit using inulin as substrate) of enzymatic activity used per gram total sugar of the substrate, pH 5.0, temperature 55℃,with stirring enzymolysis for 6 h. Under these conditions,the highest hydrolytic rate of the substrae was 98. 5 % The hydrolysate contained about 85% fructose. A 1100L of tank was used for scale up of enzymolysis. The average hydrolytic rate of substrae was 94.2% in 5 batches test.
出处
《厦门大学学报（自然科学版）》
CAS
CSCD
北大核心
1996年第6期971-976,共6页
Journal of Xiamen University：Natural Science
关键词
克鲁维酵母
菊粉酶
菊粉
酶解
酶解
Kluyveromyces sp., Inulinase, Inulin, Enzymolysis,Scale-up of enzymolysis
