高效液相色谱柱后衍生方法测定乳制品中皮革水解蛋白

本文使用岛津氨基酸柱后衍生系统锂型分析柱建立了24种氨基酸的高效液相色谱柱后衍生分析方法。5个不同浓度标准品进样（10,50,100,250,1000ug/L）,对于大多数目标物校准曲线相关系数可达0.9999;对于L（-）-羟脯氨酸,方法的检测限（S/N=3.3）为20ug/L,定量限（S/N=10）为50ug/L。连续7针进样（250ug/L,10uL）保留时间相对标准偏差为0.01-1.38,峰面积相对标准偏差为0.01-0.83。市售某两种品牌牛奶样品检测结果表明均含有L-羟脯氨酸,为皮革水解蛋白阳性样品。     

一株产溶栓酶枯草杆菌的微胶囊固定化培养

The production of ATE(anti-thrombus enzyme) from a kind of Bacillus subtilis immobilized in NaCS-PDMDAAC microcapsules was studied.The influence of mean diameter of microcapsules, concentration of PDMDAAC and the components of culture medium on the production of ATE in the condition of encapsulation culture was studied. In shaking flasks, the maximum enzyme activity in microcapsules was 1850 UK·ml -1 when the mean diameter of microcapsules was 1.60 mm, the concentration of PDMDAAC was 2.0% and the culture medium was LB culture medium(Tryptone)+glucose(0.5%)+phosphate buffer(100 ml).A bubbling culture system was designed. In this system, the maximum enzyme activity in microcapsules was 2050 UK·ml -1 , which was 3.6 times that in the condition of suspension fermentation; the maximum cell density in microcapsules was 4.89×10 9cells·ml -1 , which was 2.7 times that in the condition of suspension fermentation.     

离子阱飞行时间串联质谱定性检测禽肉中的罗丹明B

本文使用离子阱飞行时间串联质谱(LCMS-IT-TOF)快速检测了禽肉中的非法添加物罗丹明B。对加标样品进行了液质联用多级质谱分析,分别进行了MS1和MS3两种模式下的分子式预测,结果表明MS3模式下分子式预测能减少候选化合物数量,增加预测结果准确性。推测出了罗丹明B可能的五级质谱裂解规律。对加标样品和实际样品分别进行了MS4分析,两者谱图一致,表明实际样品中存在罗丹明B。     

一株产溶栓酶枯草杆菌的微胶囊固定化培养

引　言临床上常采用一些具有激活血液中纤维蛋白酶原的激活剂 ,使纤溶酶原转变为纤维蛋白的溶解酶 ,以使纤维蛋白溶解 ,从而达到预防和治疗心脑血管疾病的目的 .目前应用的溶栓药物主要有链激酶、尿激酶 (ＵＫ) [1] 等 .本文中的溶栓酶具有直接溶栓和纤溶酶原激活双重功能 ,是一种很有发展潜力的新型溶血栓药物 .ＮａＣＳ -ＰＤＭＤＡＡＣ(硫酸纤维素钠 -聚二甲基二烯丙基氯化铵 )生物微胶囊具有制备方法简单、膜物理化学性质稳定及机械强度好等优点 ,受到国际上的重视与研究[2～ 6] .本文拟用ＮａＣＳ -ＰＤＭＤＡＡＣ微胶囊进行枯草杆菌产…