HPLC法同时测定鸡矢藤中熊果酸和齐墩果酸的含量

目的：建立高效液相色谱法同时测定鸡矢藤中熊果酸和齐墩果酸的含量。方法：色谱柱为DiamonsilTM C18（250×4.6 mm,5滋m）,流动相为甲醇-0.05mol.L-1磷酸溶液（93∶7）为流动相,检测波长210 nm,进样量10滋L。结果：熊果酸在21.28滋g.mL-1～212.8滋g.mL-1范围内线性关系良好（r=0.9997）,平均回收率为97.79%（RSD=1.30%）;齐墩果酸在24.02滋g.mL-1～240.2滋g.mL-1范围内线性关系良好（r=0.9996）,平均回收率为98.36%（RSD=1.11%）。结论：该方法简便、灵敏、准确,可用于鸡矢藤药材的质量评价。     

反相高效液相色谱法测定鹿衔草中熊果酸和齐墩果酸的含量

建立反相高效液相色谱法测定鹿衔草中熊果酸和齐墩果酸含量,并进行方法学考察.采用Kromasil C18分析柱(4.6 mm×250 mm,5 μm);流动相为甲醇-水(88:12);柱温25 ℃;流速0.8 mL/min;检测波长210 nm.熊果酸进样量在0.922～18.44 μg,齐墩果酸进样量在0.506～10.12 μg范围内呈良好线性关系,其中熊果酸平均回收率为98.5%,RSD为2.13%(n=6);齐墩果酸平均回收率为 101.3%,RSD为1.69%(n=6).本方法使鹿衔草中主要成分熊果酸和齐墩果酸达到基线分离,操作简便、结果可靠,可为鹿衔草质量控制和评价提供有效手段.     

高效液相色谱法测定肌肽滴眼液中L-肌肽的含量及有关物质

目的:建立肌肤滴眼液中L-肌肤的含量测定的HPLC方法.方法:采用Kromasil NH2色谱柱(200 mm × 4.6mm,5 μm),流动相为乙腈-40 mmol·L-1磷酸氢二钾溶液(44:56,磷酸调pH 6.3).流速1.0 mL·min-1,检测波长为210 ml,柱温为35℃.结果:肌肤在9.93～99.3μg·mL-1范围内线性关系良好(r=0.999 8),平均回收率为99.8%(RSD=1.0%,n=9),滴眼液中含L-肌肽的标示百分含量为97.0%～102.0%.结论:该方法操作简便、重复性好、专属性强,可用作肌肤滴眼液中L-肌肽的质量控制.     

紫元益消丸的质量标准研究

目的:建立紫元益消丸的质量控制方法.方法:采用薄层色谱法鉴定蜈蚣,紫河车,鸡内金和蟾酥各味药材;高效液相色谱法测定蟾酥中华蟾酥毒基和脂蟾毒配基的含量.结果:紫元益消丸中的蟾酥、蜈蚣、紫河车、鸡内金的薄层色谱具有鉴别特征,斑点清晰;华蟾酥毒基在0.09-0.46 μg· mL-1范围内线性关系良好(r=0.9943),平均回收率95.57％,RSD为2.27％(n=5);脂蟾毒配基在0.16-1.01 μg·mL-1范围内线性关系良好(r=0.9984),平均回收率94.53％,RSD为2.06％(n=5).结论:鉴别方法专属性强、灵敏度高;定量方法简便快速、结果准确且重复性好,可用于紫元益消丸的质量控制.     

RP-HPLC法测定枇杷叶中熊果酸和齐墩果酸的含量

目的:建立枇杷叶中熊果酸和齐墩果酸的含量测定方法.方法:采用RP-HPLC法测定,色谱柱为ZorbaxODS柱,用甲醇-1%醋酸水溶液(88:12)为流动相,检测波长为215 nm.结果:熊果酸和齐墩果酸的平均回收率分别为98.1%,97.3%(n=3),RSD分别为1.78%,1.93%(n=3).结论:本法准确、灵敏、快速,可作为枇杷叶药材及其制剂的质量控制方法之一.     

HPLC-DAD法测定血满草中熊果酸和齐墩果酸的含量(英文)

建立了HPLC-DAD法测定血满草中熊果酸和齐墩果酸含量,并进行方法学考察。采用HPLC-DAD进行分析,fusion-RP C18柱(4.6 mm×250 mm,4μm),甲醇-0.2%磷酸水溶液(90∶10)为流动相,检测波长210 nm,体积流量1.0 mL/min。同时采用微波辅助提取、回流提取、索氏提取、冷浸提取、超声提取五种方法对血满草中熊果酸和齐墩果酸含量进行测定并比较不同方法所得结果的差异,还比较了血满草不同部位中熊果酸和齐墩果酸的含量差异。测定结果表明熊果酸进样量在3.6～8.4μg范围内,齐墩果酸进样量在3.2～16μg范围内,呈良好线性关系。血满草中熊果酸和齐墩果酸平均回收率分别为98.3%和101.4%(n=5),相对标准偏差分别为1.13%和0.72%(n=5)。五种方法比较得出索氏提取得熊果酸和齐墩果酸含量最高;血满草花中熊果酸和齐墩果酸含量最高,而根中含量最低。该方法使血满草中熊果酸和齐墩果酸达到基线分离,操作简便,结果稳定可靠。     

HPLC法测定直立白薇中对羟基苯乙酮和2,4-二羟基苯乙酮的含量

建立了中药直立白薇中对羟基苯乙酮和2,4-二羟基苯乙酮的HPLC含量测定方法。色谱条件为:ZOR-BAXSB-C18(4.6mm×250mm,5μm),流动相甲醇:0.1%醋酸水溶液(35:65),流速1.0mL/min,检测波长275nm。对羟基苯乙酮在1.04～104.00μg/mL范围内线性关系良好(r=0.9999),2,4-二羟基苯乙酮在0.25～25.00μg/mL范围内线性关系良好(r=0.9999),其平均加样回收率分别为95.40%和93.28%,RSD分别为3.71%和1.63%。本方法操作简便,结果可靠,重现性好,为白薇的质量标准研究提供了实验依据。     

RP-HPLC同时测定喙果绞股蓝中芦丁和槲皮素的含量

目的:建立RP-HPLC同时测定喙果绞股蓝中芦丁和槲皮素含量的方法,并揭示其含量动态变化规律。方法:采用大连依利特SinoChromODS-APC18色谱柱(250 mm×4.6 mm,5μm),流动相:甲醇-0.4%磷酸水溶液梯度洗脱,流速:1 mL/min,检测波长:364 nm,柱温:30℃。结果:芦丁在0.1525～3.8120μg范围内线性关系良好,r=0.9998,平均回收率为98.2%(RSD=2.0%);槲皮素在0.0589～1.4720μg范围内线性关系良好,r=0.9999,平均回收率为97.7%(RSD=2.3%)。含量测定结果表明芦丁和槲皮素的含量具季节性动态变化,芦丁8月份含量高,平均质量分数达6.31 mg/g,槲皮素9月份含量最高,平均质量分数达0.86 mg/g。结论:该方法简单,准确度高,为喙果绞股蓝的质量控制提供实验依据,芦丁和槲皮素含量动态变化规律为其开发利用提供参考。     

桂黄降脂颗粒质量标准研究

目的:建立桂黄降脂颗粒的质量标准。方法:采用薄层色谱法对桂黄降脂颗粒中山楂、丹参进行定性鉴别;采用HPLC法对山楂中的槲皮素和丹参中的丹参素钠进行含量测定。结果:薄层色谱斑点清晰、分离度效果较好、且阴性无干扰;槲皮素在11.2~33.6μg范围内呈良好的线性关系,r=0.9995(n=5),样品平均回收率为98.00%,RSD 1.33%;丹参素钠在0.0166~0.332 mg·mL-1范围内呈良好的线性关系,r=0.9998(n=5),样品平均回收率为97.87%,RSD 1.35%。结论:该方法准确可靠、专属性强、重现性好,可以作为控制桂黄降脂颗粒质量的有效方法。     

HPLC法测定酮洛芬在大鼠血浆中的浓度

目的:建立大鼠血浆中酮洛芬的HPLC测定方法,进行酮洛芬微乳凝胶的药物动力学研究.方法:血浆样品采用甲醇沉淀蛋白方法处理,萘普生钠为内标;色谱柱为DiamosilC18(200mm× 4.6mmi.d,5μm),流动相为甲醇-0.01 mol·L-1磷酸二氢钾(70:30,磷酸调pH3.0),流速1 mL·min-1,检测波长为255 nm.进样量为20μL,柱温为室温.结果酮洛芬与内标萘普生钠完全分离且血浆中内源性物质对酮洛芬的含量测定无影响;酮洛芬在0.2～50 μg·mL-1范围内线性关系良好,r=0.999 8;最低定量限为0.05μg·mL-1;日内和日间精密度均(RSD)小于2.4%;回收率为91.3%～107.2%.结论:所用方法灵敏、准确、重复性好、回收率高,可用于酮洛芬微乳凝胶的血药浓度检测.     

Abscisic Acid ELISA: Organic Acid Interference

Consideration must be exercised in determination of buffers and solutions used when carrying out enzyme-linked immunosorbent assays (ELISAs). A commercial monoclonal antibody kit for abscisic acid (Idetek, Inc.) gives significant false-positives with tricarboxylic acid cycle intermediates. The organic acids or contaminants interfered with ELISA assays for ABA as indicated by deviations in the slopes of standard curves of ABA in the organic acids. The interference, in the case of α-ketoglutarate, was caused by a contaminant. Of the organic buffers tested—Tris, Tricine, and Hepes—only Hepes showed false-positive ABA. In addition, we present data indicating the presence of ABA in commercial mannitol and provide a simple procedure for removal of the ABA.     

乳酸菌酸胁迫反应机制研究进展

乳酸菌可发酵糖类产生乳酸,并广泛应用于食品、药物和饲料等工业。由于有机酸的积累,乳酸菌大部分的生长代谢都在低pH的酸性环境中进行,具有酸胁迫反应。pH的自我平衡、ATR反应机制、对大分子的保护和修复作用及细胞膜的变化等是乳酸菌酸胁迫反应的主要机制,其中,pH自我平衡包括F0F1-ATPase质子泵、精氨酸脱氨酶途径(ADI)和谷氨酸脱羧酶途径(GAD)等。由此可见,乳酸菌酸胁迫反应机制涉及到基因和蛋白的表达调控等,是非常复杂的网络调控体系。     

Enzymatic Formation of Hexadecenoic Acid from Palmitic Acid

Desaturation of palmitic acid was investigated in an enzyme system prepared from rat liver. 2-trans-Hexadecenoic acid as well as 9-cis-hexadecenoic acid (palmitoleic acid) were found to be formed as monoenoic acid in this system.     

Acid Orcein-Iron and Acid Orcein-Copper Stains for Elastin

Paraffin sections of formol-fixed tissues stained 4-18 hr in 70% alcohol containing 1% orcein and 1% of concentrated (12 N) HCl by volume yield the familiar purple brown elastin and red nuclei on a pink background. When sections so stained are transferred directly from the stain to 70% alcohol containing 0.02% ferric chloride (FeCl₃·6 H₂O) or 0.02% copper sulfate (CuSO₄·5 H₂O) for a 15 sec to 3 min period, elastin coloration is changed to black or reddish black and chromatin staining to reddish black. The procedure can be counterstained with picro-methyl blue to yield blue collagen and reticulum or with our flavianic acid, ferric chloride, acid fuchsin mixture to give deep yellow background and deep red collagen.     

乌索酸与齐墩果酸衍生物的合成进展

乌索酸和齐墩果酸在多种植物中均有分布.二者互为同分异构体,均属于五环三萜类化合物,由于其结构多样性而具有广泛的生物活性,包括抗肿瘤、抗氧化、抗艾滋病、抗溃疡、抗炎、免疫调节等功能.有关这两种活性物质的衍生化研究一直为科研人员所关注,本文主要综述了近10年来二者衍生物合成方面的新进展,为寻找活性先导化合物、合理设计药物分子提供依据.     

Quinone-Amino Acid Conjugates Targeting Leishmania Amino Acid Transporters

The aim of the present study was to investigate the feasibility of targeting Leishmania transporters via appropriately designed chemical probes. Leishmania donovani, the parasite that causes visceral leishmaniasis, is auxotrophic for arginine and lysine and has specific transporters (LdAAP3 and LdAAP7) to import these nutrients. Probes 1–15 were originated by conjugating cytotoxic quinone fragments (II and III) with amino acids (i.e. arginine and lysine) by means of an amide linkage. The toxicity of the synthesized conjugates against Leishmania extracellular (promastigotes) and intracellular (amastigotes) forms was investigated, as well their inhibition of the relevant amino acid transporters. We observed that some conjugates indeed displayed toxicity against the parasites; in particular, 7 was identified as the most potent derivative (at concentrations of 1 µg/mL and 2.5 µg/mL residual cell viability was reduced to 15% and 48% in promastigotes and amastigotes, respectively). Notably, 6, while retaining the cytotoxic activity of quinone II, displayed no toxicity against mammalian THP1 cells. Transport assays indicated that the novel conjugates inhibited transport activity of lysine, arginine and proline transporters. Furthermore, our analyses suggested that the toxic conjugates might be translocated by the transporters into the cells. The non-toxic probes that inhibited transport competed with the natural substrates for binding to the transporters without being translocated. Thus, it is likely that 6, by exploiting amino acid transporters, can selectively deliver its toxic effects to Leishmania cells. This work provides the first evidence that amino acid transporters of the human pathogen Leishmania might be modulated by small molecules, and warrants their further investigation from drug discovery and chemical biology perspectives.