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1.
电渗析法分离提纯N-乙酰-L-半胱氨酸研究   总被引:2,自引:1,他引:1  
使用我校由辐射法制备的高性能离子交换膜HF—1及HF—2,采用电渗析技术对合成所得的N-乙酰-L-半胱氨酸进行了分离提纯,脱盐率>15%,损失率<15%,为工业化应用提供了依据。  相似文献   

2.
用几种氢过电位较高的金属Sn、Bi、NiZn以及Cu修饰铅电极,用于电解合成L-半胱氨酸的反应,首先筛选出性能较好的Sn、Ni、Zn电极,然后对该三种金属的合金进行研究,筛选出性能优越的(Ni-Sn)/Pb电极,电极活性大为提高,反应同期转化率明显提高。  相似文献   

3.
(Ni-Sn-M_xO_y)/Pb改性复合电极电解合成L-半胱氨酸的反应   总被引:1,自引:0,他引:1  
在(Ni-Sn)/Pb合金修饰电极中添加某些金属氧化物进行改性,用于电解合成L-半胱氨酸反应。结果证明,添加WO3后电极反应活性大大加强,反应同期转化率有较大提高,选择性也有所提高,添加稀土金属氧化物能有效降低反应阴极过电位,使反应选择性有所提高,但是电极稳定性还有待改善。  相似文献   

4.
电导滴定法分析氨基酸含量   总被引:3,自引:1,他引:2  
提出和建立了适用于中间控制的氨基酸分析方法即电导滴定法,测定甘氨酸,DL-天冬氨酸和L-半胱氨酸的含量,并与甲醛滴定法、凯氏定氮法作了比较,本法快速,简单,准确,易于推广。  相似文献   

5.
比色法测定复合氨基酸注射液中的N-乙酰-L-半胱氨酸   总被引:1,自引:0,他引:1  
根据N-乙酰-L-半胱氨酸与氯化钯(PdCl2)反应,生成一种稳定的黄色化合物,我们建立了比色测定复合结晶氨基酸注射液中的NAC的方法。测定波长为375nm,检测结果重现性好,变异系数是3.9%,回收率范围在93.1%~100.2%之间,检测下限为0.163μg/ml。该方法比经典的电量滴定法灵敏度高、精确性好,较高压液相色谱法操作简便、费用低。  相似文献   

6.
草鱼肠道对L-亮氨酸和L-苯丙氨酸的吸收   总被引:6,自引:0,他引:6  
利用离体灌注法研究草鱼肠道对L-亮氨酸和L-苯丙氨酸的吸收规律。结果表明,草鱼肠道对两种氨基酸的吸收是一种逆浓度、需要转运载体的主动吸收方式。通过动力学特征分析表明,草鱼肠道对L-亮氨酸的吸收率强于L-苯丙氨酸,而肠道对L-苯丙氨酸的跨壁运输能力强于L-这氨酸。由氨酸酸浓度对吸收率的影响建立的动力学参数为Leu:Jmax=0.732μmol/g.min,kt=51.60mmol/L;Phe:Jma  相似文献   

7.
L—山梨糖脱氢酶的纯化及性质的研究   总被引:12,自引:2,他引:10  
从5L罐发酵L-山梨糖的Gluconibacter oxydans SCB329和Bacillus thuringiensis SCB933混合菌株中差速离心收集SCB329菌体,破碎,离心获得无细胞抽提液,硫酸铵分级沉淀蛋白后依次经DEAE Cellulose 52和Q Sepharose FF柱层析分得到了L-册梨糖脱氢酶(SDH),它能将L-册梨糖脱氢氧化为L-册梨酮,SDS-PAGE电泳测  相似文献   

8.
NO对大鼠睡眠-觉醒的调节   总被引:10,自引:0,他引:10  
目的和方法:通过对大鼠侧脑室微量注射NOS抑制剂L-NAME及NO的前体L-精氨酸(L-Arg)观察两种物质对大鼠睡眠-觉醒的影响。结果:注射1mg L-NAME(5μL)后4h觉醒(W)明显增加,尤以注射后第1 ̄2h显著;4h慢波睡眠(SWS)明显减少,该效应同样以注射后第1 ̄2h显著;异相睡眠(PS)无明显变化。小剂量L-NAME(0.2mg,5μl)对大鼠的W、SWS、PS无明显影响;同样方  相似文献   

9.
从生产半胱氨酸的废母液中回收胱氨酸的工艺研究   总被引:4,自引:1,他引:4  
研究了一种从生产半胱氨酸的废母液中回收胱氨酸的工艺,介绍了工艺过程并讨论了其主要原理及影响因素。该方法工艺简单,操作方便,对设备的要求低,而回收率、产品含量均较高,是一种回收利用氨基酸、减少环境污染的好方法。  相似文献   

10.
新组合菌系氧化葡萄糖酸杆菌SCB329-苏芸金芽杆菌SCB933能在较长时间内保持高的转化活力且具有极强的抗杂菌污染的特性。在一次投糖分批发酵的基础上,探索在控制溶氧、PH,温度等条件下,分批加入L-山梨糖发酵生产2-酮基-L-古龙酸新工艺。采用新工艺,既充分利用了菌系的优良特性,又避免了高糖浓度可能对菌系造成的不良影响。L-山梨糖最终浓度达到14%(W/V),产酸120-135g/l,转化率90  相似文献   

11.
东北地区乳菇属的初步研究   总被引:1,自引:0,他引:1  
本文报道了东北地区乳菇属(Lactarius)的29种,其中包括新种2个,长白乳菇(L.chanbainensis Y.Wang et Xie sp.nov.)温泉乳菇(L.wenquanensis Y.Wang et Xie sp.nov.);国内新记录种5个:茶绿乳菇[L.necator(Pers.ex Fr.)Farst.],条纹乳菇[L.oculatus(Peck)Burl.],变红乳菇[L.acris(Bolt.ex Fr.)Gray],复生乳菇(L.repraesentaneus Britz.)和点柄乳菇(L.maculatus Burl.)。新种有汉文和拉丁文描述以及形态、显微构造图;国内新记录种有汉文描述。  相似文献   

12.
ABSTRACT. A method for discriminating among Leishmania is described, based upon small subunit ribosomal DNA sequence differences. The method was to amplify the entire 2.2 kb small subunit rDNA by polymerase chain reaction using conserved primers specific for the 5' and 3' termini of the small subunit ribosomal RNA, and then hybridize the product dotted onto nylon membranes with labeled oligonucleotides. The design of the hybridization probes was based upon complete small subunit rDNA sequences from L. amazonensis, L. major and L. guyanensis and partial sequences of L. mexicana, L. braziliensis, L. tropica and L. chagasi. A high degree of sequence similarity (> 99%) among species was found. However, sufficient sequence divergence occurred to permit the design of internal oligonucleotide probes specific for species complexes. This procedure successfully discriminated amongst a wide range of Leishmania isolates. The method detected as few as 10 cultured organisms and detected parasites in tissue samples from experimentally infected animals. Non-radioactive labeling showed the same specificity and sensitivity as radioactive probes.  相似文献   

13.
Aims: The gram‐positive bacterial genus Lactococcus has been taxonomically classified into seven species (Lactococcus lactis, Lactococcus garvieae, Lactococcus piscium, Lactococcus plantarum, Lactococcus raffinolactis, Lactococcus chungangensis and Lactococcus fujiensis). This study aimed to develop a novel multiplex polymerase chain reaction (PCR) primer set for the identification of the seven lactococcal species, as well as to differentiate the two industrially important dairy subspecies, L. lactis subsp. lactis and L. lactis subsp. cremoris. Methods and Results: A multiplex PCR primer set was designed based on the nucleotide sequences of the 16S rRNA gene of the seven lactococcal species. The specificity of the established one‐step multiplex PCR scheme was verified using more than 200 bacterial strains, in which a complete sequence match was confirmed by partial sequencing of their 16S rRNA gene. Conclusions: The one‐step multiplex PCR enables the identification and speciation of bacterial strains belonging to the genus Lactococcus and the differentiation of strains of L. lactis subsp. lactis and L. lactis subsp. cremoris. Significance and Impact of the Study: This work provides an efficient method for identification of lactococcal strains of industrial importance.  相似文献   

14.
本文报道松树上散斑壳属(Lophodermium Chev)的7个种,其中3个新种:安徽散斑壳(L.anhuiense Y.R.Lin sp.nov.)、白皮松散斑壳(L.pini—bungeanae Y.R.Lin sp.nov.)及奇异散斑壳(L.mirabile Y.R.Lin sp.nov.);2个我国新记录种:针叶树散斑壳(L.conigenum(Brunaud)Hilitz.)和南方散斑壳(L.australe Dearn.);2个国内已记载的种:松针散斑壳(L.pinastri(schrad.)Chev.)和乔松散斑壳(L.pini-excelsae Ahmad)。文中列出了分种检索表,对新种作了拉丁文和汉文描述,对新记录种的主要特点以及已知种的寄主新记录和地理新分布分别作了记载。  相似文献   

15.
松树上的七种散斑壳   总被引:3,自引:0,他引:3  
本文报道松树上散斑壳属(Lophodermium Chev)的7个种,其中3个新种:安徽散斑壳(L.anhuiense Y.R.Lin sp.nov.)、白皮松散斑壳(L.pini—bungeanae Y.R.Lin sp.nov.)及奇异散斑壳(L.mirabile Y.R.Lin sp.nov.);2个我国新记录种:针叶树散斑壳(L.conigenum(Brunaud)Hilitz.)和南方散斑壳(L.australe Dearn.);2个国内已记载的种:松针散斑壳(L.pinastri(schrad.)Chev.)和乔松散斑壳(L.pini-excelsae Ahmad)。文中列出了分种检索表,对新种作了拉丁文和汉文描述,对新记录种的主要特点以及已知种的寄主新记录和地理新分布分别作了记载。  相似文献   

16.
17.
This paper deals with some species of Lunathyrium Koidz. in N. E. Asia; including the eastern mountainous district of N. E. China; Far East Region of U. S. S. R.; Korea and Japan.  相似文献   

18.
国产十五种翠雀族植物的核型研究   总被引:10,自引:2,他引:8  
本文报道了国产乌头属Aconitum L.12种和翠雀属Delphinium L.3种植物的染色体数目和核型。花葶乌头A.scaposum var.scaposum和聚叶花葶乌头A.scaposum var.vaginatum的核型公式为2n=2m+6sm+8st;两色乌头A.alboviolaceum为2n=16=2m+6sm(2sat)十8st;高乌头A.sinomontanum var.sinomontanum为2n=16=4m+4sm+8st,而狭盔高乌头A.sinomontanum var.angustius为2n=32=6m+6sm+20st(1sat);褐紫乌头A.brunneum为2n=16=2m(1sat)+14sm 松潘乌头A.sungpanense为2n=16=6m(2sat)+10sm(2sat);弯枝乌头A.arcuatum为2n=16=4m+12sm;乌头A.carmichaeli为2n=32=10m+22sm;北乌头A.kusnezoffii为2n=32=10m十22sm;鸭绿乌头A.jaluense为2n=32=10m+22st;伏毛铁棒锤A.flavum为2n=16=2m+14sm; 铁棒锤A.pendulum为2n=16=4m+12sm;缩梗乌头A.sessiliflorum为2n=16=2m+10sm+4st;展毛翠雀花D.kamaoense var.glabrescens 为2n=16=2m+6sm+8st;蓝翠雀花D.caeruleum为2n=16=2m+6sm+8st;多枝翠雀花D.maximowiczii为2n=16=2m+6sm+8st。其中花葶乌头、狭盔高乌头、褐紫乌头、松潘乌头、鸭绿乌头、伏毛铁棒锤、缩梗乌头、展毛翠雀花、蓝翠雀花、多枝翠雀花的染色体数目和核型为首次报道。  相似文献   

19.
The growth of axillary shoots was initiated on nodal stem segments, excised from aseptically grown seedlings of Gentiana acaulis L., G. cruciata L., G. lutea L. and G. purpurea L. In later subcultures, a basal callus tissue developed on the shoots, giving rise to de novo formed buds. Optimum benzyladenine and indoleacetic acid combinations for shoot development were established. They were slightly different in the four species. From 35-70% of shoots rooted spontaneously, except in G. lutea, in which adventitious roots were induced by applying naphthaleneacetic acid. It was conduded that the four Gentiana species were amenable to propagation in vitro. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

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