Analysis Of Anthraquinones Research Articles

Polyethylene glycol assisted mechanical amorphous dispersion using water for the extraction of hydrophobic anthraquinones from aloe

In this study, a rapid, environmental, economical, and practical method, polyethylene glycol (PEG) assisted mechanical amorphous dispersion using water for the extraction of hydrophobic anthraquinones in crops was first proposed. In order to fully understand the factors affecting the extraction yield, a systematic study was carried out by single factor tests and response surface methodology (RSM). The corresponding influence parameters including the type of dispersant, the amount of dispersant, grinding time, extraction time, and solid-liquid ratio were optimized. Subsequently, RSM was used for multifactor experiments and the optimum conditions were 242.67 mg of PEG 100000, 4.91 min of grinding time, 4.60 min of extraction time, and 10 mL of water, respectively. To verify the feasibility of this method, the solution extracted was then analyzed by high performance liquid chromatography/quadrupole-time of flight mass spectrometry. The results showed that this method had good linearity (R2 higher than 0.99), stable intra-day precision, and inter-day precision with relative standard deviations ranging from 0.04 to 2.07% and 0.22–3.00%, satisfactory reproducibility of 0.02–6.23% for all analytes. Finally, this method was successfully used for the extraction and analysis of anthraquinones from aloe.

Presence of anthraquinone in coffee and tea samples. An improved methodology based on mass spectrometry and a pilot monitoring programme.

Anthraquinone has been linked to potential adverse effects on human health and the environment. The most commonly employed methods for the analysis of coffee and tea cause the extraction of matrix interferents such as the methylxanthines caffeine and theobromine, which hinder the analysis of anthraquinone. A new manual extraction method - using ethyl acetate as the extraction solvent with a dispersive solid-phase extraction clean-up step based on primary-secondary amines - has been developed. The new developed method allows for the quantitation of anthraquinone at 5 μg kg-1 concentration levels, four times lower than the current maximum residue limit for coffee and tea in the European Union (20 μg kg-1). Alongside, a new automated extraction method has also been developed. Finally, a pilot monitoring programme of 90 coffee and tea samples from several countries within the European Union has been performed, in which anthraquinone has been detected in a concentration range of 5.1-18.8 μg kg-1 in 32% of the monitored samples, below the current 20 μg kg-1 maximum residue limit, and in 48% of the monitored tea samples, revealing the need for including anthraquinone in a more extensive monitoring programme of tea.

Analysis of anthraquinones in rhubarb (Rheum palmatum and Rheum officinale) by supercritical fluid chromatography

The first report on the separation of five anthraquinones (chrysophanol, physcion, emodin, aloeemodin, and rhein) from rhubarb by supercritical fluid chromatography indicates that this technique is an interesting analytical alternative not just for non-polar substances. Within less than five minutes the compounds could be baseline resolved, using a mobile phase comprising supercritical carbon dioxide and methanol with 0.05% diethylamine. The optimum stationary phase showed to be an Acquity UPC2 HSS C18 SB 1.8µm column, operated at a flow rate of 2ml/min and a temperature of 30°C. Method validation confirmed that the developed procedure is selective, linear (R2≥0.999), accurate (recovery rates: 95.4% to 103.1%), and precise (intra-day≤6.9%, inter-day≤4.7%); the limit of detection was below 0.5ng on-column. The analysis of plant extracts was feasible with acceptable repeatability (σrel≤3.8%), and it determined 0.3 to 0.7% of free aglyca in the native samples. After hydrolysis according to the European Pharmacopoeia, a rise in the total content up to 2.1% was observed, with rhein being the most dominant derivative in nearly all specimens.

Separation and quantitative analysis of anthraquinones in Morinda officinalis How. by HPLC

Separation and quantitative analysis of anthraquinones in Morinda officinalis How. by HPLC

Analysis of anthraquinones in Rumex crispus by micellar electrokinetic chromatography

A micellar electrochromatographic method was performed for the analysis of the pharmaceutically important anthraquinones from the root of Rumex crispus. The separation of 1,5-dihydroxy-3-methylanthraquinone ( 1); 1,3,5-trihydroxy-6-hydroxymethylanthraquinone ( 2); 1,5-dihydroxy-3-methoxy-7-methylanthraquinone ( 3) was achieved in 6 min using a running buffer containing 10 mmol/l sodium borate, 50 mmol/l sodium dodecylsulfate, and 25% acetonitrile at pH 10.6. The method is simple, rapid, and reproducible.

Analysis of anthraquinones in Rubia tinctorum L. by liquid chromatography coupled with diode-array UV and mass spectrometric detection.

A liquid chromatographic (LC) method for the separation of both anthraquinone glycosides and aglycones in extracts of Rubia tinctorum was improved. For on-line MS detection atmospheric pressure chemical ionisation as well as electrospray ionisation (ESI) were used. The glycosides were ionised in both positive and negative ionisation (NI) mode, the aglycones only in the NI mode. With ESI ammonia was added to the eluent post-column to deprotonate the compounds. The efficiency of mass detection of the hydroxyanthraquinone aglycones was found to depend on the pKa value of the component. LC-diode-array detection and LC-MS provide useful complementary information for the identification of anthraquinones in plant extracts, which was proven with the identification of munjistin and pseudopurpurin.

Analysis of Anthraquinones by Micellar Electrokinetic Capillary Chromatography

Analysis of Anthraquinones by Micellar Electrokinetic Capillary Chromatography

Analysis of Anthraquinones by Micellar Electrokinetic Capillary Chromatography

A micellar electrokinetic capillary chromatographic method for the separation of anthraquinone positional isomers was established. The running electrolytes used in this method were 0.03 M sodium dodecyl sulphate (SDS) in 0.03 M borate buffer (pH 9) containing 10% acetonitrile for dihydroxy- and dihydroxy-methoxy-methylanthraquinones, 0.08 M SDS in 0.03 M borate buffer (pH 9) containing 10% acetonitrile for dimethoxyanthraquinones, and 0.03 M SDS in 0.08 M borate buffer (pH 8) containing 10% acetonitrile for hydroxy-methoxy- and dihydroxy-methylanthraquinones, each with an applied voltage of 20 kV. This method is simple, rapid and reproducible. © 1997 John Wiley & Sons, Ltd.