Isomerization of Retinyl Palmitate Using Conventional Lipid Extraction Solvents

Abstract The use or a chlorotorm-ethanol-water solvent system for the direct extraction of retinyl palmitate isomers from fortified food products was previously shown to be unsuitable because significant isomerization of all-trans-retinyl palmitate occurred during the extraction. This study investigated the extent of isomerization of retinyl palmitate in various extraction solvents when subjected to gold fluorescent laboratory light. Purified solutions of all-trans-retinyl palmitate in hexane were diluted with methyl t-butyl ether, hexane, methylene chloride, and stabilized chloroform and subjected to gold fluorescent laboratory light for 2, 4, and 6.5 h. Similar solutions were subjected to light or kept in the dark for 3.5 h. All-trans-, 9-cis-, and 13-cis-retinyl palmitate esters in the solutions were determined by using normal phase high performance liquid chromatography with fluorometric detection. Results demonstrated a noticeable increase in the 9-cis-retinyl palmitate concentration and a corresponding decrease in all-trans-retinyl palmitate concentration with time, in chloroform and methylene chloride compared with hexane. Chlorinated solvents in the absence of light did not promote isomerization of retinyl palmitate. Use of chlorinated solvents for the extraction of vitamin A esters should be avoided because they promote isomerization of retinyl palmitate when subjected to light, including gold fluorescent laboratory light.

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Quantitative Analysis of Sulpiride and Impurities of 2-Aminomethyl-1-Ethylpyrrolidine and Methyl-5-Sulphamoyl-2-Methoxybenzoate in Pharmaceuticals by High-Performance Thin-Layer Chromatography and Scanning Densitometry

Journal of AOAC International ◽

10.1093/jaoac/82.4.825 ◽

1999 ◽

Vol 82 (4) ◽

pp. 825-829 ◽

Cited By ~ 3

Author(s):

Danica Agbaba ◽

Tatjana Miljkovic ◽

Valentina Marinkovic ◽

Dobrila Zivanov-Stakic ◽

Sote Vladimirov

Keyword(s):

Quantitative Analysis ◽

Thin Layer ◽

High Performance ◽

Methylene Chloride ◽

Solvent System ◽

Ammonia Solution ◽

Dosage Forms ◽

Raw Material ◽

Layer Chromatography

Abstract A simple and reliable thin-layer chromatographic method for determining sulpiride and impurities of 2-aminomethyl-1-ethylpyrrolidine and methyl-5-sulphamoyl-2-methoxybenzoate was developed and validated. A methylene chloride–methanol–ammonia solution (25%; 18 + 2.8 + 0.4, v/v) solvent system is used for separation and quantitative evaluation of chromatograms. The chromatographic plate is first scanned at 240 nm to locate chromatographic zones corresponding to sulpiride and methyl-5-sulphamoyl-2-methoxybenzoate. Then 2-aminomethyl-1-ethylpyrrolidine is derivatized in situ with ninhydrin, and resulting colored spots are measured at 500 nm. The method is reproducible and convenient for quantitative analysis and purity control of sulpiride in its raw material and in its dosage forms.

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Standardisation Study of Kwatha Curnas

E-Journal of Chemistry ◽

10.1155/2004/729261 ◽

2004 ◽

Vol 1 (5) ◽

pp. 251-255

Author(s):

M. K. Santosh ◽

D. Shaila ◽

I. Sanjeeva Rao

Keyword(s):

High Performance ◽

Solvent System ◽

High Performance Liquid Chromatographic ◽

Organic Analysis ◽

Hplc Fingerprint ◽

Visible Spectrophotometry ◽

Water Solvent ◽

Mother And Child ◽

Uv Visible ◽

Ethanol Extracts

The present paper deals with the standardization of kwatha curnas such as dhanyapanchak kwatha curna, guduchyadigana kwatha curna and stanyajanankashaya curna. These are the important Ayurvedic formulations used for peri-natal care of mother and child health. Standardization of kwatha curnas were achieved by physico-chemical analysis, qualitative inorganic and organic analysis, thin layer chromatography (TLC), UV- visible spectrophotometry and high performance liquid chromatographic (HPLC) fingerprint studies. TLC study of kwatha curnas was carried out in Ethyl acetate: Methanol: Water solvent system. Ethanol extracts of kwatha curnas were used for UV- visible spectrophotometry and qualitative HPLC fingerprint study.

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Beta-carotene determined in serum by liquid chromatography with an internal standard.

Clinical Chemistry ◽

10.1093/clinchem/29.6.1042 ◽

1983 ◽

Vol 29 (6) ◽

pp. 1042-1044 ◽

Cited By ~ 26

Author(s):

W J Driskell ◽

M M Bashor ◽

J W Neese

Keyword(s):

Liquid Chromatography ◽

High Performance ◽

Methylene Chloride ◽

Internal Standard ◽

Beta Carotene ◽

Solvent System ◽

Peak Height ◽

Reversed Phase ◽

Human Populations ◽

Relationship Of

Abstract We describe a procedure for quantitative determination of beta-carotene in human serum. The 0.1-mL serum sample is precipitated with ethanol containing the internal standard, dimethyl-beta-carotene, then extracted with hexane. This extract is injected onto a reversed-phase, "high-performance" liquid-chromatography column, and the carotenes are resolved and eluted with an acetonitrile/methylene chloride isocratic solvent system. They are quantified from the peak-height ratios of their absorbance at 450 nm. About 14 min is required for each chromatogram. The procedure has excellent precision and is appropriate for routine use in analysis of large numbers of samples. The method should be particularly useful for clinical studies on the relationship of serum beta-carotene and cancer incidence in human populations.

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Chlorine-free processed high performance organic solar cells

RSC Advances ◽

10.1039/c4ra01783h ◽

2014 ◽

Vol 4 (32) ◽

pp. 16681-16685 ◽

Cited By ~ 22

Author(s):

O. Synooka ◽

K.-R. Eberhardt ◽

H. Hoppe

Keyword(s):

Solar Cells ◽

Power Conversion Efficiency ◽

Conversion Efficiency ◽

Organic Solar Cells ◽

High Performance ◽

Power Conversion ◽

Chlorinated Solvents ◽

Solvent System ◽

Chlorinated Solvent

In this work, we demonstrate the successful replacement of a chlorinated solvent system based on a 1 : 1 mixture of chlorobenzene and ortho-dichlorobenzene with the chlorine-free solvent xylene, resulting in chlorine-free processing with a small amount of diiodooctane additive. In fact, the overall power conversion efficiency is improved from 6.71% for the chlorinated solvents to 7.15% for the chlorine-free solvent m-xylene.

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High Performance Liquid Chromatographic Determination of Vitamin A in Margarine, Milk, Partially Skimmed Milk, and Skimmed Milk

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/63.4.894 ◽

1980 ◽

Vol 63 (4) ◽

pp. 894-898 ◽

Cited By ~ 5

Author(s):

James N Thompson ◽

George Hatina ◽

William B Maxwell

Keyword(s):

Vitamin A ◽

High Performance ◽

Chromatographic Determination ◽

Solvent System ◽

High Performance Liquid Chromatographic ◽

Retinyl Palmitate ◽

Aqueous Alcohol ◽

Skimmed Milk ◽

Liquid Chromatographic ◽

Β Carotene

Abstract Saponification and subsequent evaporation of extracts can cause losses of vitamin A during analysis and thus cause erratic results. These steps were therefore avoided by measuring retinyl palmitate and β-carotene directly in hexane extracts of milk and margarine. Extracts were purified before high performance liquid chromatography(HPLC) by washing with aqueous alcohol. Retinyl palmitate was measured at 325 nm after chromatography on LiChrosorb Si60, 5 μm, using ethyl ether–hexane (2+98) as the solvent system. Milk (2 mL) was shaken with absolute ethanol (5 mL) and hexane (5 mL). Water (3 mL) was added and, after mixing and centrifugation, 100 μL hexane layer was injected. Margarine (5 g) was dissolved in hexane (100 mL). After 5 mL of the hexane solution was washed with 60% ethanol and centrifuged, a 50 μL aliquot was injected. The results of the retinyl palmitate estimation in milk agreed with those obtained by a fluorometric method; the results in margarine agreed with those obtained by saponification, extraction, and HPLC. The coefficients of variation on analysis of 10 replicate samples of milk and margarine were 3 and 4.5%, respectively. The analysis of margarine for vitamin A was completed by measuring β-carotene with a detector set at 453 nm; the coefficient of variation of this measurement was 3% (10 replicates).

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Application of Gel Permeation Chromatography and Nonaqueous Reverse Phase Chromatography to High Performance Liquid Chromatographic Determination of Retinyl Palmitate and α-Tocopheryl Acetate in Infant Formulas

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/65.4.810 ◽

1982 ◽

Vol 65 (4) ◽

pp. 810-816 ◽

Cited By ~ 7

Author(s):

William O Landen

Keyword(s):

High Performance ◽

Methylene Chloride ◽

Gel Permeation Chromatography ◽

High Performance Liquid Chromatographic ◽

Retinyl Palmitate ◽

Tocopheryl Acetate ◽

Infant Formulas ◽

Rp Hplc ◽

Liquid Chromatographic

Abstract A high performance liquid chromatographic (HPLC) method was developed for determining retinyl palmitate and α-tocopheryl acetate in infant formulas. The lipid-soluble components were extracted from the aqueous phase by homogenizing in a solvent mixture of isopropanol and methylene chloride with magnesium sulfate added to remove water. The vitamins were fractionated from the lipid material by using high pressure gel permeation chromatography (HP-GPC) followed by quantitation using nonaqueous reverse phase (RP)-HPLC. Three μStyragel (lOOÅ) columns connected in series were used for HP-GPC fractionation of sample extracts in methylene chloride. A Zorbax ODS (6 μm) column and methylene chloride-acetonitrile-methanol (30 + 70 + 0.2) were used for RP-HPLC quantitation. The 32 commercial infant formulas that were analyzed represent a wide variety of formulations manufactured at various fortification levels. Vitamin A results ranged from 89 to 242% of the declared levels. Vitamin E values, determined as the supplemental form a-tocopheryl acetate, ranged from 83 to 272% of the' declared levels. Determination of vitamin A in 6 samples and vitamin E in one sample by this method and the official AOAC method gave comparable results. This method, which requires no saponification, was successfully used to determine vitamins A and E in ready-to-use, liquid concentrated, and powdered infant formulas.

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Method Validation and Simultaneous Determination of Retinol, Retinyl Palmitate, β-Carotene, α-Tocopherol and Vitamin C in Rat Serum Treated with 7,12 Dimethylbenz[a]Anthracene and Plantago major L. by High- Performance Liquid Chromatography Using Diode-Array Detection

Combinatorial Chemistry & High Throughput Screening ◽

10.2174/1386207311316020008 ◽

2013 ◽

Vol 16 (2) ◽

pp. 142-149

Author(s):

Abdulkadi Levent ◽

Gökhan Oto ◽

Suat Ekin ◽

İsmet Berber

Keyword(s):

High Performance Liquid Chromatography ◽

High Performance ◽

Retinyl Palmitate ◽

Diode Array ◽

Diode Array Detection ◽

Plantago Major ◽

Rat Serum ◽

Array Detection ◽

Β Carotene

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Conversion of glucose into furans in the presence of AlCl3 in an ethanol–water solvent system

Bioresource Technology ◽

10.1016/j.biortech.2012.03.126 ◽

2012 ◽

Vol 116 ◽

pp. 190-194 ◽

Cited By ~ 122

Author(s):

Yu Yang ◽

Changwei Hu ◽

Mahdi M. Abu-Omar

Keyword(s):

Solvent System ◽

Water Solvent

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Comparative Study of Anti-Gouty Arthritis Effects of Sam-Myo-Whan according to Extraction Solvents

Plants ◽

10.3390/plants10020278 ◽

2021 ◽

Vol 10 (2) ◽

pp. 278

Author(s):

Yun Mi Lee ◽

Eunjung Son ◽

Dong-Seon Kim

Keyword(s):

Uric Acid ◽

Serum Uric Acid ◽

Proinflammatory Cytokines ◽

High Performance ◽

Weight Bearing ◽

Gouty Arthritis ◽

Extraction Solvents ◽

Main Components ◽

Factor Α ◽

Necrosis Factor

Sam-Myo-Whan (SMW) has been used in Korean and Chinese traditional medicine to help treat gout, by reducing swelling and inflammation and relieving pain. This study compared the effects of SMW extracted by using different solvents, water (SMWW) and 30% EtOH (SMWE), in the treatment of gouty arthritis. To this end, we analyzed the main components of SMWW and SMWE, using high-performance liquid chromatography (HPLC). Anti-hyperuricemic activity was evaluated by measuring serum uric acid levels in hyperuricemic rats. The effects of SMWW and SMWE on swelling, pain, and inflammation in gouty arthritis were investigated by measuring affected limb swelling and weight-bearing, as well as by enzyme-linked immunosorbent assays, to assess the levels of proinflammatory cytokines and myeloperoxidase (MPO). In potassium oxonate (PO)-induced hyperuricemic rats, SMWW and SMWE both significantly decreased serum uric acid to similar levels. In monosodium urate (MSU)-induced gouty arthritis mice, SMWE more efficiently decreased paw swelling and attenuated joint pain compare to SMWW. Moreover, SMWE and SMWW suppressed the level of inflammation by downregulating proinflammatory cytokines (interleukin-1β, tumor necrosis factor-α, and interleukin-6) and MPO activity. HPLC analysis further revealed that berberine represented one of the major active ingredients demonstrating the greatest change in concentration between SMWW and SMWE. Our data demonstrate that SMWE retains a more effective therapeutic concentration compared to SMWW, in a mouse model of gouty arthritis.

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