A simple method for purifying silica gel for column chromatography

1988 ◽  
Vol 65 (10) ◽  
pp. 891 ◽  
Author(s):  
Antonio E. Guarconi ◽  
Victor F. Ferreira
Keyword(s):  
Silica Gel ◽  
Column Chromatography ◽  
Simple Method

Determination of Benzo (a) pyrene in Foods

1978 ◽  
Vol 61 (1) ◽  
pp. 129-135
Author(s):  
Yukio Saito ◽  
Hiroshi Sekita ◽  
Mitsuharu Takeda ◽  
Mitsuru Uchiyama
Keyword(s):  
Sulfuric Acid ◽  
Silica Gel ◽  
Column Chromatography ◽  
Analytical Method ◽  
Selective Extraction ◽  
Acid Extraction ◽  
Simple Method ◽  
Extraction Step ◽  
Concentrated Sulfuric Acid

Abstract An analytical method was developed for determining benzo (a) pyrene in foods, suitable for routine use. The method consists of 4 cleanup steps: (1) alkali cleavage of sample, (2) preliminary silica gel column chromatography, (3) selective extraction with concentrated sulfuric acid, and (4) further silica gel column chromatography. Recoveries of benzo- (a) pyrene added to 50 g (or 10 g) food at levels of 0.4 ppb (or 2 ppb) ranged from 70% for short-necked clam and mackerel to 85% for chicken meat. The sulfuric acid extraction step affords a simple method for isolating benzo (a)- pyrene from various kinds of interfering substances which could not be separated by existing methods.

scholarly journals A Simple Method for Preparation of Pure Isomers of Methyl Linoleate Hydroperoxide by Dry Silica Gel Column Chromatography

1985 ◽  
Vol 34 (12) ◽  
pp. 1029-1031
Author(s):  
Kazuo MIYASHITA ◽  
Toshiyuki CHIBA ◽  
Kazuhiko HATA ◽  
Kenshiro FUJIMOTO ◽  
Takashi KANEDA
Keyword(s):  
Methyl Linoleate ◽  
Silica Gel ◽  
Column Chromatography ◽  
Linoleate Hydroperoxide ◽  
Simple Method ◽  
Methyl Linoleate Hydroperoxide

scholarly journals Comparison of Cleanup Techniques for Simple Method for Analysis of Selected Organophosphorus Pesticide Residues in Molluscs

1996 ◽  
Vol 79 (1) ◽  
pp. 123-131 ◽  
Author(s):  
Félix Hernández ◽  
Roque Serrano ◽  
Joaquim Beltran ◽  
Francisco J López
Keyword(s):  
Silica Gel ◽  
Column Chromatography ◽  
Pesticide Residues ◽  
High Speed ◽  
Mytilus Galloprovincialis ◽  
Organophosphorus Pesticides ◽  
Organophosphorus Pesticide ◽  
Gas Chromatograph ◽  
Simple Method

Abstract A simple method for determination of 5 organo phosphorus pesticides (dimethoate, chlorfenvin phos, chlorpyrifos, methidathion, and phosmet) in molluscs (Mytilus galloprovincialis and Venus gallina) was developed, with special attention to cleanup. Organophosphorus pesticides were extracted with acetonitrile-acetone (90 + 10, v/v) in a high-speed blender. Two cleanup procedures were used to defat extracts prior to injection into a gas chromatograph: liquid-liquid partition with acetoni trile-hexane and adsorption column chromatography with silica gel. The latter was more efficient for elimination of fat and fractionation of pesticides with different polarities. Limits of detection of the overall procedure including extraction and cleanup ranged from 0.2 to 1 ng/g. Quantitative recoveries for pesticide concentrations ranging from 1 to 10 000 ng/g were obtained.

A Cytotoxic Natural Product from Patrinia villosa Juss

2019 ◽  
Vol 19 (11) ◽  
pp. 1399-1404 ◽  
Author(s):  
Yangcheng Liu ◽  
Wei Liu ◽  
Changlan Chen ◽  
Zheng Xiang ◽  
Hongwei Liu
Keyword(s):  
Cell Cycle ◽  
Cell Lines ◽  
Silica Gel ◽  
Column Chromatography ◽  
Bioactive Compound ◽  
Antitumor Agent ◽  
2D Nmr ◽  
Preparative Hplc ◽  
Dependent Manner ◽  
2D Nmr Spectra

Background and Purpose:: Patrinia villosa Juss is an important Chinese herbal medicine widely used for thousands of years, but few reports on the ingredients of the herb have been presented. In this study, we aim to isolate the bioactive compound from the plant. Material and Methods:: The air-dried leaves of P. villosa (15kg) were extracted three times with 70% EtOH under reflux. The condensed extract was suspended in H2O and partitioned with light petroleum, dichloromethane and n-BuOH. The dichloromethane portion was then subjected to normal-phase silica gel column chromatography, ODS silica gel column chromatography and semi-preparative HPLC to yield compound 1. Cytotoxicities of 1 were assayed on HepG2, A549 and A2780 cell lines. The mechanism of apoptosis and cell cycle on A549 was confirmed subsequently. Results: A new impecylone (Impecylone A) was isolated from the leaves of Patrinia villosa Juss, and its structures were established using 1D, 2D-NMR spectra and HR-ESI-MS. Impecylone A could selectivity inhibit HepG2 and A549 cell lines. The compound could induce apoptosis of A549 and arrest the cell cycle at G2/M phase in a dose-dependent manner. Conclusion: Impecylone A is a novel compound from Patrinia villosa Juss and could be a potential antitumor agent especially in the cell lines of A549.

scholarly journals Separation of lipids by Silica Gel G column chromatography

1964 ◽  
Vol 5 (3) ◽  
pp. 479-481
Author(s):  
Quincy E. Crider ◽  
Petar Alaupovic ◽  
Joe Hillsberry ◽  
Cathy Yen ◽  
Reagan H. Bradford
Keyword(s):  
Silica Gel ◽  
Column Chromatography

scholarly journals Anti-Neuroinflammatory and Anti-Inflammatory Activities of Phenylheptatriyne Isolated from the Flowers of Coreopsis lanceolata L. via NF-κB Inhibition and HO-1 Expression in BV2 and RAW264.7 Cells

2021 ◽  
Vol 22 (14) ◽  
pp. 7482
Author(s):  
Hwan Lee ◽  
Zhiming Liu ◽  
Chi-Su Yoon ◽  
Linsha Dong ◽  
Wonmin Ko ◽  
...  
Keyword(s):  
Silica Gel ◽  
Column Chromatography ◽  
Raw264.7 Cells ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Etoac Fraction ◽  
Factor Alpha ◽  
Anti Inflammatory ◽  
And Oxidative Stress ◽  
Necrosis Factor

Aging is associated with immune disregulation and oxidative stress which lead to inflammation and neurodegenerative diseases. We have tried to identify the anti-neuroinflammatory and anti-inflammatory components of Coreopsis lanceolata L. The dried flowers of C. lanceolata were extracted with 70% EtOH, and the obtained extract was divided into CH2Cl2, EtOAc, n-BuOH, and H2O fractions. The CH2Cl2 fraction was separated using silica gel and C-18 column chromatography to yield phenylheptatriyne (1), 2′-hydroxy-3,4,4′-trimethoxychalcone (2), and 4′,7-dimethoxyflavanone (3). Additionally, the EtOAc fraction was subjected to silica gel, C-18, and Sephadex LH-20 column chromatography to yield 8-methoxybutin (4) and leptosidin (5). All the compounds isolated from C. lanceolata inhibited the production of nitric oxide (NO) in LPS-induced BV2 and RAW264.7 cells. In addition, phenylheptatriyne and 4′,7-dimethoxyflavanone reduced the secretion of inflammatory cytokines, tumor necrosis factor alpha (TNF-α), and interleukin (IL)-6. Among them, phenylheptatriyne was significantly downregulated in the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2). Subsequently, phenylheptatriyne also effectively inhibited nuclear factor-kappa B (NF-κB) activation in LPS-stimulated BV2 and RAW264.7 cells. Based on these results, the anti-neuroinflammatory effect of phenylheptatriyne isolated from C. lanceolata was confirmed, which may exert a therapeutic effect in treatment of neuroinflammation-related diseases.

ChemInform Abstract: Asymmetric Synthesis of a 3-Acyltetronic Acid Derivative, RK-682, and Formation of Its Calcium Salt During Silica Gel Column Chromatography.

ChemInform ◽  
2010 ◽  
Vol 32 (28) ◽  
pp. no-no
Author(s):  
Mikiko Sodeoka ◽  
Ruriko Sampe ◽  
Sachiko Kojima ◽  
Yoshiyasu Baba ◽  
Naoko Morisaki ◽  
...  
Keyword(s):  
Asymmetric Synthesis ◽  
Acid Derivative ◽  
Silica Gel ◽  
Column Chromatography ◽  
Calcium Salt

In vitro 19-norandrogen synthesis by equine placenta requires the participation of aromatase

1995 ◽  
Vol 144 (3) ◽  
pp. 517-525 ◽  
Author(s):  
S Moslemi ◽  
P Silberzahn ◽  
J-L Gaillard
Keyword(s):  
Silica Gel ◽  
Aromatase Inhibitors ◽  
Column Chromatography ◽  
Microsomal Fraction ◽  
Specific Activity ◽  
Reverse Phase Hplc ◽  
Reverse Phase ◽  
Term Placenta ◽  
Flow Detector

Abstract Explants of equine full-term placenta have been shown to synthesize 19-norandrogens from labelled androgens. Steroid metabolites were purified by silica-gel column chromatography then analysed and quantified by C18-reverse-phase HPLC coupled to a radioactive flow detector. 19-Norandrostenedione was subsequently recrystallized to constant specific activity, providing unequivocal evidence of its synthesis by the equine placenta. 19-Norandrostenedione synthesis appeared to be localized in the microsomal fraction. Regardless of the substrate used, formation of 19-norandrogens was far weaker than that of oestrogens; moreover, the yield of 17-oxosteroids produced was much greater than that of 17β-hydroxysteroids, suggesting the presence of a dehydrogenase with predominant oxidative activity. Sulphoconjugated steroids formed were less than 0·5% of total steroids. Although 19-nortestosterone could not be generated by equine purified aromatase incubated with labelled testosterone, the synthesis of 19-norandrogens and oestrogens by equine placental explants was blocked by two specific aromatase inhibitors, 4-hydroxyandrostenedione and fadrozole. Our results provide evidence for a placental origin of at least a part of the 19-norandrogens previously identified in the blood of the pregnant mare. Furthermore, it is suggested that 19-norandrogen biosynthesis would involve the enzymatic metabolism of 19-oxygenated androgens formed by equine aromatase. Journal of Endocrinology (1995) 144, 517–525

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