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1.
Melanoma is an enormous global health burden, and should be effectively addressed with better therapeutic strategies. Therefore, new therapeutic agents are needed for the management of this disease. The aim of this study was the investigation of cytotoxic activity of some isoquinoline alkaloid standards and extracts obtained from Sanguinaria canadensis—collected before, during, and after flowering—against three different human melanoma cells (A375, G361, SK-MEL-3). The cytotoxicity of these extracts was not previously tested on these melanoma cell lines. Determination of alkaloid contents was performed by HPLC-DAD using Polar RP column and mobile phase containing acetonitrile, water, and 1-butyl-3-methylimidazolium tetrafluoroborate. The cytotoxicity of alkaloid standards was investigated by determination of cell viability and calculation of IC50 values. Significant differences were observed in the alkaloids content and cytotoxic activity of the extracts, depending on the season of collection of the plant material. In the Sanguinaria canadensis extracts high contents of sanguinarine (from 4.8543 to 9.5899 mg/g of dry plant material) and chelerythrine (from 42.7224 to 6.8722 mg/g of dry plant material) were found. For both of these alkaloids, very high cytotoxic activity against the tested cell lines were observed. The IC50 values were in the range of 0.11–0.54 µg/mL for sanguinarine and 0.14 to 0.46 µg/mL for chelerythrine. IC50 values obtained for Sanguinaria canadensis extracts against all tested cell lines were also very low (from 0.88 to 10.96 µg/mL). Cytotoxic activity of alkaloid standards and Sanguinaria canadensis extracts were compared with the cytotoxicity of anticancer drugs—etoposide, cisplatin, and hydroxyurea. In all cases except the one obtained for cisplatin against A375, which was similar to that obtained for Sanguinaria canadensis after flowering against the same cell line, IC50 values obtained for anticancer drugs were higher than the IC50 values obtained for sanguinarine, chelerythrine, and Sanguinaria canadensis extracts. Our results showed that Sanguinaria canadensis extracts and isoquinoline alkaloids, especially sanguinarine and chelerythrine, could be recommended for further in vivo experiments in order to confirm the possibility of their application in the treatment of human melanomas.  相似文献   
2.
《Analytical letters》2012,45(23-24):2253-2260
Abstract

Contents of the colored cells (alkaloidal cells1) found in Macleaya cordata root and Sanguinaria canadensis rhizome were analysed quantitatively by histochemical chromatography (HC) with the help of newly modified automated micromanipulator.

These were found to have 4 alkaloids viz protopine type protopine(1) and allocryptopine(2) and benzo- [c]phenanthridine type (sanguinarine(3) and cheleryth-rine(4)) in both the plants. Quantitatively the pro-topine alkaloids were 10-40 ng per cell while the benzo-[c]phenanthridines (as chlorides) were only 1-6 ng per cell in M. cordata root. However, in S. canadensis rhizome the relative quantities of the 4 alkaloids (1), (2), (3) and (4) were found to be 10, 13, 137 and 68 ng per cell respectively.  相似文献   
3.
<正>A new derivative of triterpene named Erigeronol 1 was isolated from the EtOH extract of the aerial part of Conyza canadensis together with 15 known compounds for the first time from this plant.The structure of Erigeronol 1 was elucidated as 3-O-(hydroxyacetyl) -23,28-dihydroxy-β-amyrin by hydrolysis and spectroscopic analysis.Erigeronol 1 showed potent cytotoxic activity with IC_(50) value of 7.77±0.47μg/mL against melanoma B16 determined by the 3-(4,5-dimethylthiazo-2-yl)-2,5-diphenyltetrazolium bromide(MTT) method.  相似文献   
4.
5.
利用污水厂污泥、河道淤泥、粉煤灰和加拿大一枝黄花等废弃物为主要原料, 制备出一种污泥基陶土(SBPC), 研究了其对Pb2+、Cd2+、Ni2+、Cr3+ 4种重金属混合溶液的吸附效果, 并以Cr3+为例研究其吸附机理. 结果表明, 在低浓度重金属混合溶液中, SBPC对Cr、Pb的去除率可达90%以上, 而对Cd、Ni的去除率低于15%; 在单一重金属铬溶液中, SBPC对Cr3+的最大吸附量为4.32mg?g-1, 其吸附等温线符合Freundlich模型; 吸附机理主要包括表面沉降、阳离子置换、取代反应、Cr3+水解以及静电吸附.  相似文献   
6.
The qualitative and quantitative compositions of anthocyans from fruit of plants of the Caprifoliaceae family grown under conditions of Belgorod region were investigated. The plants included elder species [Sambucus nigra L. (I), S. canadensis (II), and S. canadensis f. sceletoniana (III)], Viburnum opulus L., and Lonicera caerulea L. It has been found that the principal anthocyans of I are cyanidin-3-sambubioside (52.5%) and cyanidin-3-glucoside (37.1%) whereas from the other two elder species the principal component was cyanidin-3-sambubioside-5-glucoside, acylated p-coumaric acid, 70.9 (II) and 54.3% (III). Fruit of the other plants did not contain acylated anthocyans. The content of anthocyans in fresh or dried fruit was determined by spectrophotometry.__________Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 132–133, March–April, 2005.  相似文献   
7.
Abstract

Bilateral band compression (BBC) is a process where a solvent flow perpendicular to the direction of development squeezes bands into a smaller area. BBC of the 10 mm wide lanes of high-performance thin-layer chromatography (HPTLC) separation resulted in more than 6 times increase in peak height and peak area of Canadian goldenrod labdane diterpenes solidagenone and presolidagenone. Simultaneously, the signal-to-noise ratio increased only up to 2.2–2.4 times due to the higher noise level. The BBC increased the relative standard deviations (RSDs) of peak height and area reached three to four times of the original as well. It is known that overpressured layer chromatography (OPLC) separates more efficiently than conventional TLC/HPTLC techniques. In order to increase the bio-detection sensitivity, we combined bioautography, BBC, and fully offline infusion-OPLC using band-shaped sample application/separation. Thyme essential oil has been applied as a multi-component object to show the potential of this process. It is demonstrated that biologically active minor components, which may be missed in case of a conventional process, can also be detected by means of this combined method.  相似文献   
8.
The aim of this work was to modify and validate the post-column high-performance liquid chromatography (HPLC)-ABTS and DPPH methods for evaluating the antioxidant activity of the methanolic extracts of Solidago canadensis (Canadian goldenrod) leaves and flowers. Separation of the analytes was performed via the HPLC-PDA method on a YMC analytical column using a gradient elution program. Three compounds with antioxidant properties – chlorogenic acid, rutin and isoquercitrin – and two unidentified antioxidants were established. The research showed that the coil temperature regimes and loop length combinations influence the optimised post-column assay method for detecting the antioxidant activity of goldenrod radical scavengers. Investigations established that the temperature in the reaction coil was a substantial factor contributing to the signal strength of the analytes after reacting with the DPPH and ABTS radicals.  相似文献   
9.
加拿大一枝黄花二萜成分的抗肿瘤活性   总被引:4,自引:0,他引:4       下载免费PDF全文
通过对4株人癌细胞系,肝癌SMMC7721,红白血病K562、乳腺癌Bcap37和肺腺癌SPC-A1的体外抑制实验发现,加拿大一枝黄花花序的石油醚、乙酸乙酯浸膏具有较强的体外抑制肿瘤细胞生长的能力,二者对上述4株肿瘤细胞的半数抑制浓度(IC50)低于50μg/mL.依据初筛结果,采用MTT法进行活性成分的跟踪检测,从乙酸乙酯浸膏中分离到两个抗肿瘤活性二萜.由NMR确定它们的结构分别是6β-当归酰克拉文酸和6β-巴豆酰克拉文酸.这两个化合物对4株肿瘤细胞株的半数抑制浓度(IC50)在7~12μg/mL.由于两个化合物对人永生化上皮细胞系HaCaT的毒性较小(IC50〉50μg/mL),加拿大一枝黄花可能成为开发抗肿瘤药物的新来源,是一种具有研究价值的草药.  相似文献   
10.
A new pyromeconic acid derivative,pyromeconic acid-3-O-β-D-glucopyranoside-3′-(O-β-D-glucopyranoside)-6′-(O-4″-hydroxybenzoate) (1),along with two known ones,were isolated from the whole plants of Conyza canadensis.Their structures were elucidated based on the analysis of their spectroscopic data.The in vitro antibacterial testing results showed that all of these three compounds were inactive towards two bacterial strains,Escherichia coli and Staphyloccocus aureus.  相似文献   
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