北五味子不同炮制品中的木脂素类成分

研究北五味子炮制前后其中木脂素类成分的变化。采用电喷雾质谱(ESI-MS)以及高效液相色谱(HPLC)分别对经过不同方法炮制后的北五味子中木脂素类成分进行研究。北五味子经过不同方法炮制后,并没有新成分的生成,只是木脂素类成分含量有不同程度的变化。并对不同的炮制方法进行了比较。该方法准确、可靠,为北五味子不同炮制品的质量评价提供了一定的科学依据。

高效液相色谱法测定山茱萸与五味子配伍前后马钱苷、没食子酸及五味子醇甲的含量

目的考察山茱萸与五味子配伍前后两药主要组分的含量变化规律。方法利用高效液相色谱(HPLC)方法,比较了配伍前后单煎液、合煎液和单煎合并液中两药主要组分马钱苷、没食子酸和五味子醇甲的含量变化。结果在配伍比例较低(≤4:4)时,五味子促进了山茱萸中马钱苷的溶出。合煎液中的没食子酸、五味子醇甲组分的百分含量随着五味子配伍比例的增大呈线性减小,且均低于单煎液。单煎合并液中这3种组分的含量均高于同比例合煎液。结论山茱萸五味子配伍对两药主要组分溶出有较大影响,该影响主要在煎煮过程中发生。

五味子中木脂素类成分的高效液相色谱-电喷雾质谱研究

采用液相色谱-电喷雾质谱联用(HPLC-ESI-MSn)技术,对北五味子与南五味子中木脂素类成分进行了系统研究.通过HPLC-ESI-MS技术,获得了相应化合物的保留时间、紫外光谱和分子量等信息,利用电喷雾多级串联质谱技术(ESI-MSn),获得了相应化合物的结构信息.研究结果表明,北五味子与南五味子的主要木脂素成分除5个共有成分外其它成分差异较大,并且其共有成分含量差别较大.在此基础上,建立了简便、快速的北五味子与南五味子药材分析鉴定的新方法.

离子液体[omim][PF_6]的生物降解性研究

以[omim][PF6]为C、N、P营养源驯化活性污泥,考察驯化前后不同活性污泥接种微生物时离子液体的生物降解性,以及在支链上添加酯基对离子液体生物降解性的影响;同时,探讨经过驯化的活性污泥对1-甲基-3-辛基咪唑阳离子基团([omim]+)生物降解的途径.结果表明,通过在支链上添加酯基,可以改善离子液体的生物降解性;以普通的活性污泥为接种微生物的密闭瓶实验表明,[omim][PF6]的生物降解率<20%,属于难生物降解的物质,进入环境后可能产生较长时间的积累;以经过驯化的活性污泥为接种微生物时,可以提高[omim][PF6]的生物降解率到60%左右;在[omim]+的生物降解过程中,会产生1-甲基咪唑阳离子的积累;对[omim]+的生物降解产物的HPLC-MS/MS分析,初步推测[omim]+的生物降解途径.

Characterization of the Microstructure of Bimodal HDPE Resin

In this work, two industrial bimodal high density polyethylene resins, resin A and resin B having similar molecular weight (M-w), molecular weight distribution (M-wD), and short-chain branching (SCB) content but different mechanical properties, were fractionated through cross-fractionation. The fractions were further, characterized by GPC, C-13 NMR, DSC AND FT IR techniques. These two resins were firstly fractionated into two franctions, i.e. high-temperature and low temperature fractions, via preparative solution crystallization fractionation. Resin A with much better mechanical properties contains more high-temperature fractions with longer crystalizable sequences. The SCB content in the low temperature fraction of resin A is lower than the of resin B. Both low-temperature fractions were then further fractionated using solvent gradient fractionation (SGF). The characterization of SGF fraction indicates that most of the branches fall into the high molecular weight chain in both low-temperature fractions.

Effects of ultrahigh pressure extraction conditions on yields and antioxidant activity of ginsenoside from ginseng

Ultrahigh pressure technique was employed to extract ginsenosides from roots of ginseng (Panax ginseng C.A. Meyer). The optimal conditions for ultrahigh pressure extraction (UPE) of total ginsenosides were quantified by UV-vis spectrophotometry with the ginsenoside Re as standard, the signal ginsenosides were quantified by HPLC and ELSD with ginsenosides Re, Rg(1), Rb-1, Rc and Rb-2 as standards. Orthogonal design was applied to evaluate the effects of four independent factors (extraction pressure, extraction temperature, extraction time and ethanol concentration) on the yield and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity of ginsenoside, which are based on microwave extraction (ME), ultrasound extraction (UE), soxhlet extraction (SE) and heat reflux extraction (HRE) method. The results showed that UPE method can produce ginsenoside with the highest yield and the best radical scavenging activity compared to other used ones. Scanning electron microscopic (SEM) images of the plant cells after ultrahigh pressure treatment was obtained to provide visual evidence of the disruption effect.

Studies on principal components and antioxidant activity of different Radix Astragali samples using high-performance liquid chromatography/electrospray ionization multiple-stage tandem mass spectrometry

The principal components, isoflavonoids and astragalosides, in the extract of Radix Astragali were detected by a high-performance liquid chromatography Couple to electrospray ionization ion trap multiple-stage tandem mass spectrometry (HPLC-ESI-IT-MSn) method. By comparing the retention time (t(R)) of HPLC, the ESI-MSn data and the structures of analyzed Compounds with the data of reference compounds and in the literature, 17 isoflavonoids and 12 astragalosides have been identified or tentatively deduced. By Virtue of the extracted ion chromatogram (EIC) mode, simultaneous determination of isoflavonoids and astragalosides could be achieved when the different components formed overlapped peaks. And this method has been utilized to analyze the constituents in extracts of Radix Astragali from Helong City and of different growth years. Then the antioxidant activity of different samples has been Successfully investigated by HPLC-ESI-MS method in multiple selected ion monitoring(MIM) mode, applying the spin trapping technology, and the Ferric Reducing Antioxidant Power (FRAP) assay was applied to support the result.

Comparative study of paclitaxel physically encapsulated in and chemically conjugated with PEG-PLA

Paclitaxel-loaded poly(ethylene glycol)-b-poly(L-lactide (LA)) (PEG-PLA) micelles were prepared by two methods. One is physical encapsulation of paclitaxel in micelles composed of a PEG-PLA block copolymer and the other is based on a PEG-PLA-paclitaxel conjugate, abbreviated as "conjugate micelles" Their physicochemical characteristics, e.g. critical micelle concentration (CMC), morphology, and micelle size distribution were then evaluated by means of fluorescence spectroscopy, scanning electron microscopy (SEM), and dynamic light scattering (DLS). The results show that the CMC of PEG-PLA-paclitaxel and PEG-PLA are 6.31 x 10(4) and 1.78 x 10(-3) g L-1, respectively. Both micelles assume a spherical shape with comparable diameters and have unimodal size distribution. Moreover, in vitro drug delivery behavior was studied by high performance liquid chromatography (HPLC). The antitumor activity of the paclitaxel-loaded micelles against human liver cancer H7402 cells was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method.

麻黄-甘草药对配伍前后主要药效成分及抗炎活性的变化

利用高效液相色谱串联质谱联用法(HPLC-MS/MS)和气相色谱质谱联用法(GC-MS)分析了麻黄与甘草药对配伍前后水煎液中主要药效成分的变化,并通过小鼠的耳廓肿胀试验考察了甘草、麻黄单煎液及药对共煎液的抗炎活性变化。分别通过HPLC法和GC-MS法对甘草与麻黄中主要化学成分,甘草酸、甘草苷、麻黄碱和甲基麻黄碱进行了定量分析,通过单煎液和药对共煎液的对比,发现麻黄与甘草配伍共煎液中麻黄碱(含伪麻黄碱)的含量增加了14.52%;甲基麻黄碱(含甲基伪麻黄碱)的含量增加了64.0%;甘草酸含量增加了13.50%;而甘草苷含量降低了19.38%。药效实验证明,甘草与麻黄配伍后抗炎作用较甘草麻黄单煎液明显增强。从而在主要成分的变化程度上揭示了甘草与麻黄配伍过程中的增效机理。

等离子体光辐射-磁场综合作用处理种子对人参中皂苷含量的影响

采用紫外可见分光光度法、ESI-MS(电喷雾质谱)与HPLC-UV(高效液相色谱)测定技术分析了等离子体种子处理机处理人参种子对所栽培人参中人参皂苷含量的影响。结果发现,人参种子受到等离子体与梯度磁场综合作用处理后,培育出的人参其总皂苷含量随磁化电流强度的改变呈现近似的正态分布。其中,在磁化线圈电流强度为1.1~1.5 A处理种子后,栽培的人参中总皂苷含量较高。建立了电喷雾质谱分析人参提取物中人参皂苷的半定量方法,方法便捷地反映了未处理及处理后的人参种子所栽培的人参中皂苷成分的含量变化。

草乌中乌头类生物碱提取方法比较研究

目的优化草乌中乌头类生物碱提取方法,比较草乌、附子生品及市售炮制品中乌头类生物碱的含量,为相关中药中生物碱的测定和临床应用提供参考。方法分别用7种提取方法提取附子中乌头类生物碱,比较各方法对3种双酯型生物碱的提取效率,并测定乌头类生药及其炮制品中乌头类生物碱含量。结果10%氨水乙醚冷浸法对3种双酯型生物碱的提取效率最高。炮制品中的乌头类生物碱含量明显低于生药,各种炮制品中乌头类生物碱的含量差别也比较大。结论采用10%氨水乙醚冷浸法,高效液相色谱-紫外光谱(HPLC-UV)法对药材中乌头类生物碱进行提取和含量测定,能真实反映药材中药效和毒性成分。不同的炮制品中各生物碱含量差别较大,临床应用应有差别。

附子煎煮与配伍应用中乌头类生物碱含量的变化及意义

目的:对比研究水浴和微波加热条件下附子中乌头类生物碱的水解规律,检测与不同中药配伍煎煮后附子中乌头类生物碱的含量变化。方法:分别以水煎煮和微波加热的方法提取附子药材,采用高效液相色谱法(HPLC)分别对其中的3种双酯型生物碱及其水解产物进行含量测定;同时检测与不同中药配伍煎煮后,附子中乌头类生物碱减少程度的差异。结果:附子水煎煮30min后,中乌头碱和次乌头碱的含量分别变为峰值的10.5%和41.9%,乌头碱完全检测不到;附子微波加热150s后中乌头碱、乌头碱和次乌头碱含量分别为峰值的59.2%、41.4%和86.6%。与生附子单煎煮比较,生附子与大黄、干姜或甘草共煎后,乌头类生物碱总含量均明显下...

Purification, sequencing and biological activity of polypeptide from velvet antler

The velvet antler polypeptide CNT14 was extracted and purified by gel filtration, ion exchange chromatography and RP C, which showed a single peak in HPLC chromatography and a single band in SDS-PAGE. The molecular weight measured by MALDI/TOF/MS spectrum was 1479. 9028. The polypeptide consisted mostly of Glu, Leu, Val, Pro. The amino acid sequence of the polypeptide was detected with ESI-MS/ MS, and the sequence was E-P-T-V-L-D-E-V-C-L-A-H-G-P. The experiments of biological activity of polypeptide CNT14 in vivo were carried out, and the results show that CNT14 has stimulant effects on the growth of rat HT22 cells. Then we produced the polypeptide CNT14 according the amino acid sequence by solid phase synthesis, confirmed the sequence of the polypeptide to be consistent with the amino acid sequence of polypeptide CNT14 which was separated from the velvet antler.

Investigation of the hydrolysis of ginsenosides by high performance liquid chromatography-electrospray ionization mass spectrometry

The hydrolysis of ginsenoside standards and the crude extracts of ginseng has been investigated at different pH values (2.4 - 11.2) using high performance liquid chromatography-electrospray ionization mass spectrometry (HPLC-ESI-MS). The experimental results indicated that the pH value of aqueous solutions is an important factor in changing the composition of ginsenosides. For (20S)-protopanaxadiol ginsenosides, ginsenosides with a large mass hydrolyzed to form hydrolysates (20S)-Rg(3) and (20R)-Rg(3) at pH 4.3. There were more hydrolyzed products observed at pH 3.3: (20S)-F-2, C-25,26 hydrated ginsenoside "C-Y-1" and "C-Y-2" (MW = 802 Da) accompanied with (20S)-Rg(3), (20R)-Rg(3). At pH 2.4, only (20R)-Rg(3), (20S)-F-2, a small quantity of (20S)-Rg(3) and three C-25,26 hydrated ginsenosides were obtained. For (20S)protopanaxatriol Re, no hydrolysates were observed at pH 4.3; it was hydrolyzed at pH 3.3 to form hydrolysates (20S)-Rg, (20R)Rg(2) and hydrated C-25,26 (MW = 802 Da) and at pH 2.4 only C-25,26 hydrated ginsenosides "C-Y-1" and "C-Y-2" (MW = 802 Da) were left in the solution. Similar hydrolysis reactions could be also observed for the crude extracts of ginseng. It showed that HPLC/ESI-MS is a fast and convenient method to study the hydrolysis of ginseng.