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1.
以短序大功劳嫩叶为材料,采用CTAB法、CTAB改良法1、CTAB改良法2、SDS法和试剂盒法五种方法提取短序十大功劳基因组总DNA,用分光光度计和琼脂糖凝胶电泳方法检测所得总DNA的纯度和得率,用ISSR-PCR扩增的方法检测所得总DNA的质量。结果表明,五种方法均能从短序大功劳叶片中提取到基因组DNA,但不同方法提取得的基因组DNA的纯度、浓度和得率存在明显的差异。CTAB改良法2和试剂盒法提取的DNA纯度高,可直接用于下游分子生物学实验,CTAB法、CTAB改良法1和SDS法提取的总DNA质量较差,不利于下游的分子生物学实验;五种方法提取的总DNA的得率在10.836~451.709μg/g之间,呈CTAB法>SDS法>CTAB改良法1>CTAB改良法2>试剂盒法的现象。此实验获得的结果可以为短序十大功劳分子生物学研究提供基础。  相似文献   
2.
The self-assembly of peptide nanotubes (PNTs) depends on the structure and chemistry of cyclic peptide (CP) monomers, having an impact on their properties, making the choice of their monomers and their characterization a great challenge. We synthesized for the first time a new set of eight original CP sequences of 8, 10, and 12 d,l-α-alternate amino acids with a controlled internal diameter from 7 to 13 Å. They present various properties (e.g., diameter, global surface charge, hydrophobicity) that can open the way to new applications. Their structure and purity were determined thanks to a capillary electrophoresis coupled to electrospray ionization mass spectrometry (CE–ESI–MS) methodology developed for the first time for this purpose. The CPs were successfully separated in a basic hydro-organic background electrolyte (BGE, pH 8.0, H2O/EtOH 50:50, v/v) and analyzed in MS positive mode. The effect of CP structure on electrophoretic mobility was studied, and the mass spectra were deeply analyzed. This methodology allowed verifying their purity and the absence of linear peptide precursors as well as their stability when stored over several months. Therefore, we have developed a new CE–ESI–MS methodology for the structure and purity control of interesting potential precursors for PNTs that could be employed as nanoplatforms in diagnostics or as pseudo sieving tools for separative purposes.  相似文献   
3.
高效的植物DNA提取方法   总被引:22,自引:0,他引:22  
利用液氮研磨植物幼芽,以苯酚─氯仿─异戊醇─核糖核酸酶法提取了大豆、菜豆、玉米、高梁等几种农作物的总DNA。所提取的DNA经岛津UV-265紫外分光光度计检测及0.6%的琼脂糖凝胶电泳,结果证明:该方法所提取的植物总DNA纯度高,片段长度整齐,约50kb左右,符合外源DNA导入作物的要求,并且DNA收率很高。  相似文献   
4.
研究不同剂量及不同白喉类毒素纯度引起的迟发型超敏反应的状况,用于指导疫苗的生产,提高疫苗的质量。以豚鼠为动物模型,采用迟发型超敏试验法,对原制白喉类毒素、精制白喉类毒素、纯化精制白喉类毒素、高纯度的精制白喉类毒素的剂量与超敏反应试验。试验结果表明,注射白喉类毒素剂量的大小与超敏反应成正相关,与纯度成负相关。剂量越大,超敏反应越强;纯度越高,超敏反应愈弱。  相似文献   
5.
重组乙肝疫苗纯度高效液相层析(HPLC)测定方法的改进   总被引:1,自引:1,他引:0  
为建立重组汉逊酵母乙肝疫苗HPLC检定方法,应用TSK-G5000PW检测系统测定汉逊酵母重组乙肝疫苗表面抗原的纯度,对不同样品处理液的配比浓度和处理时间分别进行了探讨,作者选用DTT/Tween-80作为样品处理效果优于DTT+Tween-20,1:50Tween-80与0.1mol/L等量混合为样品处理液的适宜浓度。样品处理液与等量样品混匀时间介于35s-2min时,HPLC分离效果好,结果稳定。该处理液及处理时间对CHO细胞及Merck酿酒酵母重组乙肝疫苗表面抗原的HPLC纯度测定无影响。结果表明:现有的HPLC检测系统用0.1mol/L DTT与1:50 Tween-80等量混合处理后能有效地检测不同类型重组乙肝疫苗表面抗原的纯度。  相似文献   
6.
A novel aqueous two phase system (ATPS) using trimethylamine-polyethylene glycols (TMA-PEG) to promote the extraction of C-phycocyanin (C-PC) from S.platensis was introduced. The purity of C-PC (EP) obtained in the ATPS of PEG1000/Na3PO4 was increased 2.1 times by the addition of TMA-PEG1000. The purification factor was enhanced from 2.9 to 10.1 when 65% TMA-PEG1000 was added in the system. The ATPS operation must be carried out in the pH range of 6.0-7.0 and at temperatures less than 35 °C for maintaining the stability of C-PC. The partition coefficient and recovery ratio of C-PC increased with the increasing concentration of TMA-PEG. The system parameters like TMA-PEG1000 content, tie line length (TLL), pH, temperature and phase volume ratio (Vr) were screened and optimized using the fractional factorial design and Box-Behnken experiment design. The optimized system is composed of 11.8% PEG1000/TMA-PEG1000 (w/w), 64.42% TMA-PEG1000 (w/w PEG1000) and 9.5% Na3PO4 (w/w) with 38.19% TLL (w/w) and 0.89 Vr at pH 6.5 and 25 °C. The obtained value of EP was 5.21 in one-stage ATPS and 6.7 in two-stage ATPS. The recovery ratio of C-PC in the new ATPS extraction system was more than 97%.  相似文献   
7.
硫酸铵三步盐析对藻胆蛋白纯化的影响   总被引:6,自引:0,他引:6  
主要研究了多次硫酸铵盐析对条斑紫菜藻胆蛋白提取纯化效果。对分离提取的对条斑紫菜藻胆蛋白溶液进行了3次硫酸氨溶液盐析,实验结果表明:55%饱和度可以将绝大部分藻胆蛋白盐析;采用不同组合(15%、20%、25%、30%、35%、40%、45%7个饱和度分别与50%、55%、60%3个饱和度两两组合)二步硫酸铵盐析沉淀藻胆蛋白,使R-藻红蛋白和C-藻蓝蛋白的盐析后纯度(A564/A280)分别达到了1.0和0.45以上,得率分别为1.4%和0.95%;第3次硫酸铵盐析使R-藻红蛋白、C-藻蓝蛋白的纯度分别达到了1.4和0.4以上,最终产率分别为1.3%和0.8%,而变藻蓝蛋白产率有所下降(从0.65%到0.49%),但纯度变化不大。实验证明了采用多次盐析方法可以很大程度提高藻胆蛋白纯度。  相似文献   
8.
本文通过对一种新型疫苗-PHKC精制狂犬病疫苗的全面实验室检定并与法国Vero细胞狂犬病疫苗比较,认为该疫苗安全性良好,纯度较高,与法国Vero细胞狂犬病疫苗具有相同的免疫效果。  相似文献   
9.
Despite the near elimination of caste in Fiji, Indo-Fijian Hindus widely adhere to pollution ideologies that were once associated with caste hierarchies. In this paper, I analyse how such ideologies have been transformed from demarcating caste status to indexing Hindu identity. Examining a hotly contested community debate that took place when members of a Hindu devotional singing group in Fiji were accused of praying while being ‘unclean’, I argue that the intense local interest incited by such allegations—along with highly creative acts of adherence that many Indo-Fijian women undertake to avoid similar accusations—can illuminate largely unexamined aspects of how women collectively comply with pollution prohibitions, while simultaneously investing them with further social and moral force.  相似文献   
10.
蛇毒神经生长因子生物活性研究   总被引:2,自引:0,他引:2  
从蛇毒中分离的神经生长因子(NGF),经用鸡胚背根神经节做生物活性测定,发现能促进神经节树突最大生长的最小NGF浓度为2.5ng/ml。半成品的毫克蛋白(mgP)比活性在1.54×105~5.35×105U/mgP之间。经用HPLC和SDS-PAGE电泳做纯度分析,主峰面积在95%以上。并从四种NGF成品赋形剂中选出了理想的配方  相似文献   
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