无花果曲霉菌丝球对活性艳蓝KN-R的脱色研究

生物吸附法是染料废水处理中很有前途的一种方法。本文将培养的无花果曲霉菌丝球用于蒽醌染料活性艳蓝KN-R的脱色，研究了培养时间、温度、转速、pH值及盐浓度、不同碳源、不同氮源对菌丝球脱色的影响；比较了活菌与死菌的脱色效果；探讨了菌丝球重复利用对脱色率的影响。结果表明：培养时间为72h，温度为33℃，转速为150rpm，pH值为6．0，盐浓度为0.5％，以乳糖为碳源、硝酸钠为氮源时，菌丝球对活性艳蓝KN-R的脱色效果最好：活菌对染料的吸附性能比死菌好；菌丝球在重复利用了四次后，脱色率仍达85．7％。     

黑曲霉耐热木聚糖酶XYNB在毕赤酵母中的高效表达

高比活木聚糖酶的高效表达是进一步提高木聚糖酶发酵效价、降低生产成本的有效途径.将黑曲霉木聚糖酶基因XynB(不含信号肽)克隆到分泌型表达载体pPIC9K上,线性化后电击转化巴斯德毕赤酵母GS115,G418和PCR鉴定的阳性转化子经0.5%甲醇、在28℃诱导表达.SDS-PAGE分析表明,该蛋白相对分子质量为20×103左右.优化的诱导表达条件为,每隔12 h添加0.5%的甲醇,发酵5 d后,比活达4 757 U/mg;其最适温度为55℃,最适pH为5.0,80℃处理30min后仍有74%的残余酶活.     

植物载体固定化无花果曲霉对直接冻黄G的脱色研究

利用植物载体丝瓜瓤对元花果曲霉进行固定,并对直接冻黄G进行脱色研究.同时考察了不同因素如菌龄、温度、pH、转速对直接冻黄G的脱色影响.试验结果表明:三龄菌丝脱色效果最佳,该菌在30℃、pH 6.0、90r/min的振荡条件下,经12 h它对直接冻黄G的脱色达到最佳效果.固定化细胞经8次脱色后,脱色率仍达94%以上.因此用丝瓜瓤固定无花果曲霉对处理染料污染废水具有较好的应用前景.     

CMC固定化烟曲霉活菌体小球中活性染料的解吸研究

考察了吸附在CMC(羧甲基纤维素纳)固定化烟曲霉活菌体小球中活性艳蓝KN-R和活性艳红K-2BP的解吸,并在此基础上提出了吸附-回收染料的技术思路。结果表明:pH值为12.0的75%乙醇对CMC固定化烟曲霉活菌体小球中的活性艳红K-2BP和活性艳蓝KN-R的解吸效果较好。30min内,对CMC固定化烟曲霉活菌体小球中的活性艳蓝KN-R和活性艳红K-2BP的解吸率分别为60.8%和50.4%。CMC固定化烟曲霉活菌体小球中的活性艳红K-2BP的解吸动力学符合一级指数衰减模型。CMC固定化烟曲霉活菌体小球能重复利用三次以上。     

Biosorption of low level Cd~（2＋） in water by Aspergillus sojae

以酱油曲霉（Aspergillus sojae）为吸附剂,对水溶液中微量Cd2＋进行了吸附研究.实验考察了预处理方法、菌体用量、pH、温度和吸附时间对吸附的影响,同时分析了其吸附动力学和吸附等温线特性,并对酱油曲霉菌体吸附Cd2＋的可能作用机理进行了探讨.结果表明,碱预处理的菌体吸附效果最好.在菌体用量为0.08 g时,对Cd2＋的吸附量达到最大,为0.095 mg.g-1.pH值在3.4—8之间,酱油曲霉菌体对Cd2＋的吸附效果比较稳定,其最大吸附率出现在pH 3.4.温度在15℃—30℃之间时,菌体对Cd2＋的吸附率差异很小,吸附率在88.3%—94.4%之间.二级动力学方程能很好地表征酱油曲霉吸附微量Cd2＋的过程,R2在0.99以上,其吸附平衡时间大约2.5 h,线性模型更适于描述该吸附平衡过程.SEM、FTIR分析得出,Cd2＋可能是与酱油曲霉菌体表面的羟基、酰胺基、羧基、磷酸基和胺基等基团相络合而被吸附,也可能是形成颗粒沉淀而附着在菌丝上.     

木聚糖酶基因xynB在不同大肠杆菌表达系统中的表达比较

从黑曲霉(Aspergillus niger)nl-1中克隆获得木聚糖酶基因xynB.该基因全长745 bp,含有67 bp内含子,与公布的黑曲霉xynB基因有较高的同源性.将PCR扩增的木聚糖酶成熟肽基因和含有信号肽的基因分别连接到表达载体肠杆菌Top10 F’、DH10B和两种BL21宿主中获得重组菌株.通过IPTG诱导,xynB基因在重组菌株中获得特异性表达.表达产物以胞内可溶性蛋白和不溶性包涵体形式存在.诱导4 h,重组菌株pTrc-99a-xynB[BL21 condon plus(DE3)]表达量最高,胞内酶活达到299 IU/L.重组质粒pTrc-99a-xyn B(S)在不同宿主胞内和胞外均能分泌目的蛋白,诱导10 h,胞外酶活pTrc-99a-xynB(S)[BL21 condon plus(DE3)]达到347 IU/L.而pET-20b-xynB(S)在两种BL21宿主中均不表达.经SDS-PAGE分析,以pTrc-99a和pET-20b作为表达载体时,重组蛋白相对分子质量分别约为45×103和30×103.与pET-20b相比,pTrc-99a以及自身信号肽的引导更有利于重组木聚糖酶的表达.     

单宁酶产生菌的筛选和发酵条件研究

利用富集培养技术,从天然源分离得到具有较高单宁酶活性的黑曲酶Ｎｏ．１７株（ＡｓｐｅｒｇｉｌｕｓｎｉｇｅｒＮｏ．１７）．该菌株能把五倍子中的单宁酶法水解成没食子酸,在对Ｎｏ．１７株开展产酶条件和参数优化实验的基础上,进行了实验室酶法制备没食子酸试验,并获得产物浓度为１４．１ｇ／Ｌ的没食子酸,经大孔吸附树脂分离,最终净产率达到７０％．该样品经熔点测定、元素分析、ＴＬＣ、红外等理化方法分析检测,结果均与没食子酸标样一致     

Decolorization of reactive Brilliant Blue KN-R by immobilized cells of Aspergillus ficuum

Aspergillus ficuum was immobilized with sodium alginate, and decolorization of Reactive Brilliant Blue KN-R was studied on immobilized and free Aspergillus ficuum. The optimal preparation condition of the strain immobilization was obtained by the orthogonal test, it is sodium alginate 3%, CaCl2 5%, wet mycelia 30 g/L, calcific time 8 h. It was found that the immobilized cells could effectively decolorize Reactive Brilliant Blue KN-R, the optimum temperature and pH were 33℃ and 5.0, respectively. The kinetics study of decolorization of immobilized cells showed that the decolorization of Aspergillus ficuum immobilized conformed to zero-order reaction model. The decolorization efficiency of immobilized cell compared with that of free cell in different physical conditions. Results showed that the decolorization of immobilized cells with mycelia had the best efficiency. The immobilized cells could be reused after the first decolorization.     

Decolourization of reactive brilliant blue KN-R by immobilized cells of Aspergillus ficuum

Aspergillus ficuum was immobilized with sodium alginate,and decolourization of Brilliant Blue NK-R was studied on immobilized and free Aspergillus ficuum.The optimal preparation condition of the strain immobilization was obtained by the orthogonal test,it is sodium alginate 3%,CaCl2 5%,wet mycelia 30g/L,calcific time 8h.It was found that the immobilized cells could effectively decolourize Reactive Brilliant Blue KN-R,the optimum temperature and pH were 33℃ and 5.0,respectively.The kinetics study of decolourization of immobilized eclls showed that the decolourization of Aspergillus ficuum immobilized conformed to zero-order reaction model.The decolourization efficiency of immobilized cell compared with that of free cell in different physical conditions.Results showed that the decolourization of immobilized cells with mycelia had the best efficiency.The immobilized cells could be reused after the first decolourization.     

赭曲霉43的甾醇成分研究

从赭曲霉43的菌丝体甲醇提取物中分离得到3个甾醇和1个腺苷，根据波谱数据，将它们鉴定为：5α，8α-表二氧-(20S，22E，24R)-麦角甾-6，22-二烯-3β-醇(1)、(20S，22E，24R)-麦角甾-7，22-二烯-3β，5α，6β-三醇(2)、(20S，22E，24R)-麦角甾-7，22-二烯-3β，5α，6β，9α-四醇(3)以及尿苷(4)，其中化合物3首次从曲霉属中分离得到．图2表1参16。