Simultaneous Estimation of Aloe Emodin and Emodin from Rheum emodi,Cassia alata and Aloes by HPTLC

A simple, precise, specific, accurate high performance thin layer chromatography method was developed for simultaneous estimation of aloe emodin and emodin from medicinal plants like Rheum emodi (Rhubarb), Barbados aloes (dried juice of Aloe barbadensis leaf) and Cassia alata (Candle bush). Thin layer chromatographic aluminum plates pre-coated with silica gel 60 F₂₅₄ was used as the stationary phase for chromatographic separation of the drugs. Toluene:ethyl acetate:formic acid (10:2:1 v/v/v) was selected as mobile phase and analysis was carried out in absorbance mode at iso-absorptive wavelength of 263 nm. This method shows good resolution for both drugs with retention factor 0.37±0.03 and 0.55±0.03 for aloe emodin and emodin, respectively. The regression analysis data indicated good linear relationship for the calibration plots for aloe emodin and emodin in the range of 300 - 800 ng/spot and 150 - 400 ng/spot and regression coefficient was 0.9993 and 0.9994, respectively. Validation of the method was performed according to International Conference on Harmonisation guidelines for following parameters: Accuracy, precision, limit of detection, linearity, limit of quantification, robustness and specificity. In conclusion, the developed method was found to be rapid, simple, reliable and specific for the identification and quantitation of these anthraquinones in medicinal plants and marketed formulations.     

芦荟大黄素对人永生化角质形成细胞增殖和凋亡作用研究

目的研究芦荟大黄素（AE）对人永生化角质形成细胞（HaCaT）的生长抑制效应和诱导细胞凋亡能力,探讨其治疗银屑病的可能机制。方法四甲基偶氮唑蓝（MTT）法检测芦荟大黄素对HaCaT细胞增殖的抑制作用,倒置显微镜观察细胞形态学变化,流式细胞术检测细胞周期变化及凋亡。结果芦荟大黄素质量浓度在20～80μg／mL范围内可抑制HaCaT细胞增殖且呈剂量依赖性;镜下观察到细胞稀疏,生长减慢,细胞形态拉长,细胞被阻滞于S期而凋亡。结论芦荟大黄素能抑制HaCaT细胞的增殖、诱导HaCaT细胞的凋亡。可用于治疗银屑病。     

Synthesis and Antitumor Activity of Natural Compound Aloe Emodin Derivatives

In this study, we have synthesized novel water soluble derivatives of natural compound aloe emodin 4(a–j) by coupling with various amino acid esters and substituted aromatic amines, in an attempt to improve the anticancer activity and to explore the structure–activity relationships. The structures of the compounds were determined by ¹H NMR and mass spectroscopy. Cell growth inhibition assays revealed that the aloe emodin derivatives 4d, 4f, and 4i effectively decreased the growth of HepG2 (human liver cancer cells) and NCI‐H460 (human lung cancer cells) and some of the derivatives exhibited comparable antitumor activity against HeLa (Human epithelial carcinoma cells) and PC3 (prostate cancer cells) cell lines compared to that of the parent aloe emodin at low micromolar concentrations.     

不同产地首乌藤的大黄素含量比较

目的建立首乌藤中大黄素含量测定方法，并比较不同产地首乌藤的大黄素含量。方法采用酸水解和氯仿回流提取方法制备供试品溶液，用高效液相色谱（HPLC）法测定首乌藤药材的大黄素含量。流动相为甲醇-0．2mol／L磷酸二氢钠溶液（80：20，用磷酸调pH值至3．0），检测波长为444nm，灵敏度为1．0AUFS。结果大黄素进样量在0．046～0．152μg范围内与峰面积线性关系良好（r=0．9996），加样回收率为98．94％，RSD=0．93％（n=6）。江苏（两批次）、贵州、河南、湖北产首乌藤药材的大黄素含量分别为0．0756％，0．0504％，0．1721％，0．0184％，0．055％。结论不同产地的首乌藤药材的大黄素含量差异显著。     

大黄素对大鼠近端结肠平滑肌细胞电压依赖性钾通道的影响

目的研究大黄素对大鼠近端结肠电压依赖性钾离子通道的影响，以探讨其增强结肠运动的机制。方法 采用全细胞膜片钳技术测定电压依赖性钾离子通道快速激活型钾电流及延迟整流型钾电流。结果大黄素(1～30 μmol·L^-1)浓度依赖性地阻断延迟整流性钾通道，加快电流失活，其阻断作用不需要钾通道的开放。30 μmol·L^-1大黄素可抑制快速激活型钾电流。5 μmol·L^-1大黄素对钾通道的激活动力学及失活动力学没有影响，但30 μmol·L^-1大黄素使其激活动力学曲线明显右移，斜率常数由(13.0±0.6)上升至(19.6±2.5) mV，同时也使失活动力学曲线明显右移。结论大黄素可阻断延迟整流型钾通道及快速激活型钾通道，其阻断作用不是开放阻断。     

Aloe‐Emodin Quinone Pretreatment Reduces Acute Liver Injury Induced by Carbon Tetrachloride

Aloe contains several active compounds including aloin, a C‐glycoside that can be hydrolyzed in the gut to form aloe‐emodin anthrone which, in turn, is auto‐oxidized to the quinone aloe‐emodin. On the basis of the claimed hepatoprotective activity of some antraquinones, we studied aloe‐emodin in a rat model of carbon tetrachloride (CCl₄) intoxication, since this xenobiotic induces acute liver damage by lipid peroxidation subsequent to free radical production. Twelve rats were treated with CCl₄ (3 mg/kg) intraperitoneally and six were protected with two intraperitoneally injections of aloe‐emodin (50 mg/kg; CCl₄+aloe‐emodin); six other rats were only aloe‐emodin injected (aloe‐emodin) and six were untreated (control). Histological examination of the livers showed less marked lesions in the CCl₄+aloe‐emodin rats than in those treated with CCl₄ alone, and this was confirmed by the serum levels of L‐aspartate‐2‐oxoglutate‐aminotransferase (394±38.6 UI/l in CCl₄, 280±24.47 UI/l in CCl₄+aloe‐emodin rats; P<0.05). We also quantified changes in hepatic albumin and tumour necrosis factor‐α mRNAs. Albumin mRNA expression was significantly lower only in the liver of CCl₄ rats (P<0.05 versus control) and was only slightly reduced in the CCl₄+aloe‐emodin rats. In contrast tumour necrosis factor‐α mRNA was significantly higher (P<0.05) in the CCl₄ than the control rats and almost equal in the CCl₄+aloe‐emodin, aloe‐emodin and control groups. In conclusion, aloe‐emodin appears to have some protective effect not only against hepatocyte death but also on the inflammatory response subsequent to lipid peroxidation.     

Stress Degradation Studies on Embelin

Embelin, a naturally occurring benzoquinone, is obtained from fruits of Embelia ribes, which plays a vital role in the Ayurvedic system of medicine. The benzoquinone has diverse pharmacological and therapeutic properties and now constitutes a part of modern medicine. The aim of our study was to observe the effect of various stress conditions on this potential drug candidate. Embelin was subjected to stress conditions of acid and alkaline hydrolysis, oxidation, photolysis and thermal degradation. A significant degradation was found to occur by acid hydrolysis, oxidation and to a lesser extent under thermal stress and alkaline hydrolysis; the compound was found to be stable to photolytic stress. Further, the degradation product resulting from the acid hydrolysis was isolated and its structure was elucidated using spectroscopic techniques. Stress degradation studies on embelin provide an insight for its stability and storage considering the formulation aspects of modern medicine.     

芦荟甙和芦荟大黄素的高速逆流色谱分离纯化

应用高速逆流色谱法从芦荟生药中一次性分离得到芦荟甙（纯度99．99％）和芦荟大黄素（纯度95．83％）,分别达到定量和鉴别用化学对照 品要求。     

高效液相色谱法测定肾石消胶囊中大黄素含量

目的建立测定肾石消胶囊中大黄素含量的高效液相色谱法。方法以Thermo BDS Hypersil C18柱(250 mm×4.6 mm,5μm)为固定相,甲醇-0.1%磷酸溶液(85∶15)为流动相,检测波长为254 nm,流速为1.0 mL/min,柱温为室温。结果大黄素进样量在0.265 5～5.31μg范围内与峰面积线性关系良好,r=0.999 9,平均回收率为99.43%,RSD为0.47%(n=6)。结论该方法快速、简单、准确、可用于该制剂中大黄素的含量测定。     

高效液相色谱法测定心脉神胶囊中大黄素含量

目的建立测定心脉神胶囊中大黄素含量的高效液相色谱（HPLC）法。方法色谱柱为Hypersil ODS柱（150mm×4．6mm,10μm）,流动相为甲醇-0．02mol／L磷酸（75：25）,检测波长438nm,流速1．2mL／min。结果大黄素质量浓度在0．0022～0．0110g／L范围内与峰面积值呈良好的线性关系,线性回归方程为A=33111090．9C＋396．4,r=0．9998,平均回收率为100．35％,RSD为0．96％。结论HPLC法适用于心脉神胶囊中大黄素的含量测定。     

A validated stability indicating ion-pair RP-LC method for zoledronic acid

The present paper describes the development of a stability indicating high performance liquid chromatographic (HPLC) assay method for zoledronic acid in the presence of its impurities and degradation products generated from forced decomposition studies. The drug substance was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. The degradation of zoledronic acid was observed under oxidative stress at higher temperature. The drug was found to be stable in other stress conditions attempted. Successful separation of the drug from the degradation products formed under stress conditions was achieved on a C18 column using a mixture of phosphate buffer that contains 7 mM tetra butyl ammonium hydrogen sulphate, an ion-pairing agent and methanol (95:5) as mobile phase. The developed HPLC method was validated with respect to response function, precision, accuracy, specificity and robustness. The developed HPLC method to determine the related substances and assay determination of zoledronic acid can be used to evaluate the quality of regular production samples. It can be also used to test the stability samples of zoledronic acid.     

高效液相色谱法测定妇乐颗粒中大黄素和大黄酚含量

目的 建立测定妇乐颗粒中大黄素和大黄酚含量的高效液相色谱（HPLC）法。方法色谱柱为Zorbax Extend—C18柱（250mm×4．6mm,5μm）,流动相为甲醇-0．1％磷酸溶液（80：20）,流速为1．0mL／min,柱温为30℃,检测波长为265nm。结果大黄素的进样量线性范围为0．01054—0．21080μg,r=0．9999（H=6）,平均回收率为101．69％,RSD=2．52％（n=6）;大黄酚的进样量线性范围为0．01112—0．22240μg,r=1．0000（n=6）,平均回收率为96．73％,RSD=1．74％（n=6）。结论该方法结果准确,重现性好,可作为妇乐颗粒质量控制的定量方法之一。     

中药活性成分大黄素用于治疗新型冠状病毒肺炎的可能性

2019新型冠状病毒感染已严重威胁到人们的健康和生活,但目前尚无特效治疗药物对其进行有效的防控。大黄素作为蓼科植物大黄及虎杖的主要活性成分,具有广谱的抗病毒活性,对包括SARS冠状病毒(SARS-CoV)、流感病毒、HIV病毒、HBV病毒等的感染和复制具有抑制作用。因此,本文就抗SARS-CoV的中成药及中药复方、大黄素及复方制剂抗病毒的机制、含大黄及虎杖的复方制剂抗病毒的临床研究和大黄素用于治疗新型冠状病毒肺炎(COVID-19)的可能性进行综述,旨在探讨其治疗2019新型冠状病毒的临床可能性。     

高效液相色谱法测定肤舒宁喷雾剂中大黄素和芦荟苷含量简

目的建立测定肤舒宁喷雾剂中大黄素和芦荟苷含量的高效液相色谱法。方法色谱柱采用C18柱（250mm×4. 6mm,5 μm）。大黄素测定时流动相为甲醇-0. 1%嶙酸溶液（80 ： 20）,流速l.OmL/min,检测波长为254 nm,进样量为20 μL,柱温为30℃。芦荟苷测定时流动相为乙腈-水（25 ： 75,V/V）,流速l.OmL/min,检测波长为355 nm,进样量为20 pL,柱温为301。结果以峰面积（F）对进样质量浓度（;T,（ig/mL）进行线性回归,得大黄素回归方程F = 23 151X-3 768. 2,r = 0. 999 9,线性范围为2.400？48. 00 （ig/mL,平均回收率为101.36% ’ RSD为1. 72% ;芦荟苷回归方程F = 7 220. 4 JT - 2 476, r = 0. 999 9,线性范围为5. 000 - 100. 0 （Ag/mL,平均回收率为101.11%,RSD为1.57%。结论该法操作简单,测定结果准确,重复性好,可用于肤舒宁喷雾剂中大黄素和芦荟苷的含量测定。     

反相高效液相色谱法测定妇康止痛片中大黄素含量

目的建立测定妇康止痛片中大黄素含量的反相高效液相色谱法。方法色谱柱为C18柱，流动相为甲醇-0，1％磷酸溶液（80：20），检测波长为288nm，流速为1，0mL／min，柱温为25℃。结果大黄素进样量在0，05～0．40μg范围内与峰面积呈良好的线性关系，r=0，9995，平均加样回收率为98，54％，RSD=1．65％（n=6）。结论所用方法结果准确可靠，操作简便，可用于妇康止痛片的质量控制。     

高效液相色谱法测定常通口服液中大黄素的含量

目的 :测定常通口服液中大黄素的含量。方法 :采用高效液相色谱法 ,以Nova -PakC18 为色谱柱 ,甲醇 -0 1%磷酸 (85∶15)为流动相 ,检测波长为254nm。结果 :常通口服液中大黄素的含量在0 48～2 40μg/ml浓度范围内线性关系良好 (r=0 9998)。平均回收率为99 73 % (n=5) ,RSD=1 42 %。结论 :本方法简便、快速 ,测定结果准确。     

Strategy for identification and characterization of small quantities of drug degradation products using LC and LC-MS: application to valsartan, a model drug

The present study demonstrates the applicability of a strategy involving use of liquid chromatography (LC) and liquid chromatography-mass spectrometry (LC-MS) techniques for the identification and characterization of minute quantities of degradation products, without their isolation from the reaction matrix in pure form. Valsartan was used as a model drug. It was subjected to forced degradation studies under the International Conference on Harmonisation (ICH) prescribed conditions of hydrolysis (acid, base and neutral), photolysis, oxidation and thermal stress. The drug showed lability under acid/neutral hydrolytic and photolytic conditions, while it was stable to base hydrolytic, oxidative and thermal stress. Three small degradation products were formed, which were separated on a C-18 column using a gradient method. The same were characterized with the help of their fragmentation pattern and accurate masses obtained upon LC-MS/TOF analyses and online H/D exchange studies. The structures were supported by appropriate mechanistic explanation. The strategy involving use of LC and LC-MS for the identification and characterization of minute quantities of degradation products was applied on a model drug, valsartan. Three degradation products were successfully characterised without their isolation from the reaction matrix in pure form. The structures were supported by appropriate mechanistic explanation.     

Antibacterial Activity of the Iraqi Rheum ribes. Root

Abstract

The antibacterial activity of the ethanol, aqueous, and organic extracts from the root of Rheum ribes. Linn (Polygonaceae) was examined. Four anthraquinone aglycone components, chrysopahnol, physcion, aloe emodin, and emodin, were isolated from the biologically active extract and identified by spectroscopic analysis. Emodin is recorded for the first time in this species. The MIC values of the biologically active extracts, aloe emodin, and emodin, were 500, 125, 250, and 63 µg/mL against Staphylococcus aureus., respectively. The extracts and compounds did not inhibit Pseudomonas aeruginosa. and Escherichia coli. at the highest concentration tested, 4000 and 250 µg/mL, respectively.     

大黄素电化学性质的研究

目的:研究了大黄素的电化学性质以及大黄素与牛血清白蛋白(BSA)相互作用的电化学行为。方法:采用循环伏安法和差分脉冲伏安法对大黄素进行电化学行为的研究,并在不同pH值下进行线形扫描实验;同时应用紫外-可见分光光度法对大黄素与牛血清白蛋白的结合情况进行了研究。结果:大黄素在-0.522V处出现一个明显的还原峰;大黄素与牛血清白蛋白结合生成了一种非电活性的超分子化合物,并对结合反应的机理进行了探讨。结论:大黄素的还原峰电流与扫描速率呈简单线性关系。大黄素与牛血清白蛋白结合形成非电活性的超分子化合物导致大黄素氧化还原峰电流降低,峰电位基本不变,峰电流的下降值同所加入的BSA浓度在一定范围内呈线性关系。     

A validated stability indicating LC method for oxcarbazepine

The present paper describes the development of a stability indicating reversed phase liquid chromatographic (RPLC) method for oxcarbazepine in the presence of its impurities and degradation products generated from forced decomposition studies. The drug substance was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. The degradation of oxcarbazepine was observed under base hydrolysis. The drug was found to be stable to other stress conditions attempted. Successful separation of the drug from the synthetic impurities and degradation product formed under stress conditions was achieved on a C18 column using mixture of aqueous 0.02 M potassium dihydrogen phosphate–acetonitrile–methanol (45:35:20, v/v/v) as mobile phase. The developed HPLC method was validated with respect to linearity, accuracy, precision, specificity and robustness. The developed HPLC method to determine the related substances and assay determination of oxcarbazepine can be used to evaluate the quality of regular production samples. It can be also used to test the stability samples of oxcarbazepine.