农用植物活性成分提取技术研究进展

从农用植物中提取活性成分作为植物源农药有效成分已成为当前农药化学和农药毒理学研究的热点。系统综述了溶剂提取法、水蒸气蒸馏法、升华法等农用植物活性成分常规提取技术和近年兴起的超声波提取法、微波提取法、生物酶法、超临界流体提取法、超高压提取法、亚临界提取法以及包括超声-微波协同萃取等在内的联合提取法、微切助互提取法、快速溶剂提取法、高压脉冲提取法、超滤法提取法等新兴提取技术,并对其特性、应用实例及发展前景和趋势进行了展望,旨在为农用植物活性成分的提取、开发、应用提供参考和依据。     

古DNA提取技术新进展

古DNA是揭示古代生物生长状态以及生物千百万年来进化情况的最重要的信息载体,在治疗人类遗传性的疑难病症及牲畜饲养和粮食作物种植等方面都有重大的贡献。古DNA提取技术作为获得该重要的信息载体的最重要手段,长久以来受到了世界各地的考古学家以及医学研究学者们的高度重视。随着科学的发展,古DNA提取技术已经形成多种核心方法:Chelex-100法、酚-氯仿抽提法、二氧化硅(硅粒)法、NaOH法、硅离心柱法试剂盒、磁珠法试剂盒等方法。本文将根据最新的研究成果对以上提到的几种方法进行分析比较,以期能够为将来古DNA提取技术的发展创新提供新的思路与方向。     

古DNA提取技术新进展

古DNA 是揭示古代生物生长状态以及生物千百万年来进化情况的最重要的信息载体,在治疗人类遗传性的疑难病症及牲畜饲养和粮食作物种植等方面都有重大的贡献。古DNA提取技术作为获得该重要的信息载体的最重要手段,长久以来受到了世界各地的考古学家以及医学研究学者们的高度重视。随着科学的发展,古DNA提取技术已经形成多种核心方法：Chelex-100 法、酚-氯仿抽提法、二氧化硅（硅粒）法、NaOH 法、硅离心柱法试剂盒、磁珠法试剂盒等方法。本文将根据最新的研究成果对以上提到的几种方法进行分析比较,以期能够为将来古DNA提取技术的发展创新提供新的思路与方向。     

抗癌药物紫杉醇的提取与分离纯化技术

本对紫杉醇的提取与分离纯化技术,包括柱层析法、薄层色谱法、沉淀法、胶束动电毛细管色普法、膜分离法、树脂吸附分离法、高速逆流色谱法、化学反应法和药理作用靶点法进行了较全面的综述。     

浅议膜分离技术在抗生素提取中的应用

抗生素在药物领域有着重要的作用,提取生产抗生素是药物生产的重要组成部分。因此,通过科学的方式来提取抗生素是药物科学领域的重要步骤。本文概述了通过膜分离技术来提取抗生素,而这里的膜分离技术主要包括纳滤膜、分渗透膜等多种膜分离技术,更好地为我国膜分离技术在抗生素提取上的应用发展出谋划策。     

微波技术在活性物质提取中的应用

介绍了微波提取的原理和特点,并分析出微波提取技术可以缩短实验和生产时间、降低能耗、减少溶剂用量以及废物的产生,可以提高收率和提取物的纯度,降低实验操作费用和生产成本等优点。通过对微波提取应用实例的介绍,更全面的展现了微波提取的重要性。微波提取技术提取植物中活性物质具有很高的实用价值,有待开展多方面的深入研究。     

简便、快速提取高质量的RNA分子

MethodsforHandy,RapidIsolationofHighQualityRNAbyGuanadiumThioeyauateDuJianYuanYanhuaMaShenglinDongZhiwei(BeijingInstituteforCancerResearchBeijing100034)硫氰胍是一种有效的蛋白变性剂。早在1979年,Chirgwin等就利用氯化铯／硫氰胍超离心技术成功地从RNA酶富集的胰脏组织中提取出未降解的RNA分子[2],从而使它成为抑制RNA酶的首选药物并得到广泛使用,但受到超速离心设备的限制。1983年,Cathala报道了氯化锂／硫氰胍RNA提取法[1]。该方法操作简便,获得的RNA质量很高,但所需时间较长。为了能在短时间内更快…     

双磁珠法质粒DNA提取技术及应用

质粒是基因合成与测序领域中使用最为频繁的基因运载工具,然而传统的质粒DNA提取方法面临提取通量低、生产成本高等问题,无法满足日益增长的需求。本研究基于质粒提取原理,开发了双磁珠法(double-magnetic-bead method, DMBM)质粒提取技术,探究了磁珠投入量、质粒DNA片段大小、菌液投入量等因素对质粒提取的影响,并且对比了本技术与商业化质粒DNA提取试剂盒提取DNA质量、提取通量及提取成本。结果表明,双磁珠法质粒DNA提取技术可满足不同细胞密度、不同片段长度的质粒DNA提取。此外,该技术搭载96通道全自动核酸提取仪,提取的质粒DNA纯度更高、提取时间缩短80%、提取成本缩减57.1%,从而实现了质粒DNA提取的高通量、低成本,有效助力基因合成与测序。     

黄芪多糖的闪式提取技术研究

目的:建立黄芪多糖的闪式提取技术.方法:对黄芪多糖闪式提取技术中提取温度、提取时间、提取电机电压、pH值、料液比、乙醇浓度进行了单因素实验,以多糖得率为指标确定提取工艺,并与传统碱水提取法进行了比较,最后用该工艺对8种不同产地或级别的黄芪原料进行多糖提取和含量测定.结果:初步确定提取工艺为温度65℃、提取时间2 min、pH值为10、提取电机电压200V、料液比1:10、乙醇浓度为5%(V/V),提取所得黄芪多糖总量达到123.46mg/g,比碱提法多糖得率提高了近30%,该法检测不同黄芪原料多糖含量在87.44～187.74mg/g.结论:闪式提取技术能大大提高黄芪多糖提取率,不同产地或级别的黄芪原料在黄芪多糖含量上有较大差异.     

姜黄素的提取技术研究进展

姜黄素具有抗氧化、抗炎、抗癌等药理活性,高效便捷的提取方法是其药食价值开发的关键。本文综述了姜黄素的提取方法,包括有机溶剂提取、酸碱提取、水杨酸钠法提取、微波辅助提取、超声辅助提取、超高压提取、双水相萃取、酶提取、闪式提取、超临界CO2流体萃取等,比较各方法的优缺点,分析存在问题以及提取技术未来发展方向。     

中草药化学成分研究中几种不同提取方法的比较研究

通过实验,对4种不同的提取方法进行了比较。结果表明,破碎提取法与其它方法相比,具有提取快速、完全,不需加热,节省时间、溶剂和能源,操作简单,工作效率高等优点。     

蔬菜中农药残留检测技术研究进展

对目前蔬菜中农药残留分析检测方法及其前处理过程以及快速检测技术作了综述。固相萃取(SPE)、超临界流体萃取(SFE)等新的萃取方法已逐渐代替了液-液萃取(LLE)等传统提取方法。色谱技术是农药残留分析中的重要手段。毛细管气相色谱(CGC)、高效液相色谱(HPLC)及其联用技术是现阶段农药残留分析中的主要检测方法。并指出了今后该领域的研究方向。     

Particle-loaded membranes for sample concentration and/or clean-up in bioanalysis

Solid-phase extraction nowadays is a major sample preparation tool. The latest development in this area is the introduction of particle-loaded membranes (membrane-extraction disks). The potential of these extraction membranes in bioanalysis is discussed with respect to recoveries, reproducibility, sensitivity and speed. A comparison is made between liquid-liquid extraction and solid-phase extraction using traditional sorbents and extraction disks, and off-line and on-line techniques. Particle-loaded membranes are available in disks with diameters of 4–90 mm. The 25–90 mm disks are mainly used for off-line extractions of mainly environmental samples, while the 4 mm disks are available in the so-called drug tubes that can be used in the same way as conventional extraction cartridges for the extraction of drugs from biological fluids. The main advantage of using drug tubes is the smaller desorption volume and, therefore, the increased sensitivity. Cutting smaller disks, from the commercially available disks, allows the use of on-line extractions in column-switching systems. The main conclusion is that in many cases particle-loaded membranes are more efficient than packed solid-phase extraction cartridges.     

DYNAMICS OF THE HISPID FLAGELLUM OF OCHROMONAS DANICA : The Role of Mastigonemes

High speed cinephotographic techniques were used to determine the pattern of fluid flow about the hispid flagellum of Ochromonas danica and to investigate the behavior of this flagellum in media of increased viscosity. The fluid currents are consistent with the hypothesis that the mastigonemes are passive, rigid, remain normal to the flagellar surface, and lie in the plane of flagellar undulation during motility.     

Tired of the same old grind in the new genomics and proteomics era?

New discoveries in life sciences depend on accurate analysis of biomolecules, which in turn depends on the extraction of high-quality molecules in high quantities from the tissues of plants, animals or microorganisms. The extraction process for hard-to-lyse cells and tissues has been a bottleneck in the path to discovery for many years. This review describes extraction methods currently in use, and compares them to a newly developed, automated process involving patented pressure cycling technology (PCT). The PCT sample preparation system (SPS) uses an instrument capable of rapid, temperature-controlled pressure cycling between ambient and high pressures, and single-use sample tubes containing a ram and a lysis disk. The quality and quantity of nucleic acid and protein prepared by the PCT SPS method are comparable to the older methods, whereas ease and safety of processing, reproducibility, speed and control are enhanced.     

An effective DNA extraction protocol for brown algae

Successful extraction of total DNA from brown algae, which are generally polysaccharide and polyphenol rich, is often problematic using current methods. Persistent polysaccharide and polyphenolic compounds can hinder further application of modern molecular techniques requisite to molecular‐based evolutionary studies. Our broad and long‐term research goals with fucalean taxa, especially Sargassum, and problems with existing DNA extraction methods were an impetus to develop a reliable DNA extraction method. Initial research established hexadecyltrimethylammonium bromide (CTAB) based total‐DNA methods as the most viable for further empirical development. Several constituents effective at either complexing secondary compounds or creating a reductive extraction environment were increased in concentration or added to the extraction buffer. These seemingly minor changes resulted in the creation of a highly reductive extraction buffer and effective total‐ DNA harvesting technique. We detail these modifications and demonstrate the reliability of the modified protocol with a variety of brown algae and tissue preservation methods. Such DNA is shown to be suitable for a variety of molecular techniques.     

Solubilization of antigens of Fasciola hepatica which react with antibodies to Schistosoma mansoni.

Extracts of Fasciola hepatica adult worms contain antigens reactive with antisera prepared against Schistosoma mansoni adult worms. These antigens are poorly solubilized when homogenized in a phosphate buffered saline (PBS) solution and pellet readily when subjected to high speed centrifugation. Solubilization is improved greatly by the addition of sodium dodecyl sulfate (0.03%) to the PBS. When this is done, one obtains approximately the same total amount of crude Lowry reactive material as with PBS extraction followed by high speed centrifugation but antigenic reactivity to an anti-S. mansoni antiserum increases enormously. The antigens liberated from F. hepatica SDS extraction are largely materials under 200,000 MW and over 60,000 MW.     

Modified protocols for rapid carrot genomic DNA extraction and AFLP™ analysis using silver stain or radioisotopes

AFLP^™ is one of the most frequently used techniques for identification of molecular markers. We have modified the procedures for genomic DNA extraction, AFLP product generation and silver staining in order to speed up analyses and screen large numbers of plant samples. Using this protocol, we were able to achieve an 82% reduction of costs without compromising the reliability and quality of data gathered.     

MAXIMUM SWIM SPEEDS OF CAPTIVE AND FREE-RANGING DELPHINIDS: CRITICAL ANALYSIS OF EXTRAORDINARY PERFORMANCE

Research into dolphin swimming historically was guided by false assumptions pertaining to maximum speed. Accurate measurements on swimming speed and duration of effort of free-ranging dolphins are rare. To examine the variance of maximum swimming speeds, nearly 2,000 speed measurements were obtained for both captive and free-ranging dolphins, including Tursiops truncatus, Pseudorca crassidens, Delphinus capensis , and Delphinus delpbis . Measurements were made from videotapes of dolphins trained to swim fast around a large pool or jumping to a maximum height, videotapes of captured wild dolphins immediately after release, and sequential aerial photographs of a school of free-ranging dolphins startled by a passing airplane. Maximum horizontal speeds for trained animals were 8.2 m/sec for T. truncatus , 8.0 m/sec for D. delphis , and 8.0 m/sec for P. crassidens . Maximum speeds for T. truncatus swimming upwards, prior to vertical leaps ranged from 8.2 to 11.2 m/sec. Wild T. truncatus demonstrated a maximum speed of 5.7 m/sec. Maximum swimming speed of free-ranging D. capensis responding to multiple passes by a low flying airplane was 6.7 m/sec. There was no evidence that the freeranging dolphins have superior swimming capabilities to captive animals. The results of this study imply that realistic maximum swimming speeds for dolphins are lower than previous reports which were based on sparse data and imprecise measurement techniques.