florisil column chromatography
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2021 ◽  
Vol 4 (Vol4) ◽  
pp. 31-37
Author(s):  
Moawiya Haddad

Although most of the organochlorine pesticides have been banned from use and trade in Jordan, their residues remain still present in different environmental and food matrices. Because of the need to clarify the current status of pesticide contamination in Jordan, the present study has investigated the extent of contamination in camel milk, meat, and liver. One hundred eighty samples of camel milk, meat, and liver have been analyzed for their residual contents of dichlorodiphenyltrichloroethane and related metabolites, hexachlorohexane isomers, aldrin, dieldrin, endrin, heptachlor, heptachlor epoxide, and hexachlorobenzene. These samples were Soxhlet-extracted, cleaned up using florisil-column chromatography, and analyzed using a gas chromatographic system equipped with the electron-capture detector. Results: 31.7, 35, and 38.8% of the examined milk, meat, and liver samples, respectively, were contaminated with organochlorine pesticides. In general, obtained results have confirmed that pesticide contamination is still a significant concern when speaking of environmental samples and food in Jordan. More research is needed in this ambit. The pesticide contamination appears relevant enough in camel milk and liver samples, suggesting the need for reliable maximum residue levels where absent.


2004 ◽  
Vol 87 (5) ◽  
pp. 1063-1069 ◽  
Author(s):  
Emiko Mochizuki ◽  
Takao Yamamoto ◽  
Yoshihiro Mimaki ◽  
Yutaka Sashida

Abstract A method is described for determination of the steroidal saponin, eruboside B, originating in garlic and garlic products as the p-nitrobenzoyl chloride (PNBC) derivative by reversed-phase liquid chromatography (with ultraviolet detection at 260 nm. Proto-eruboside B was extracted from garlic (Allium sativum L.); subjected to solid-phase extraction (SPE) with a C18 cartridge, Florisil column chromatography, and silica gel column chromatography; and then enzymatically converted to eruboside B, which was applied as an external standard. Steroidal saponins in garlic and commercial garlic products were extracted with methanol and purified by SPE cartridges, followed by enzymatic treatment. A frostanol saponin such as proto-eruboside B is enzymatically transformed to a spirostanol saponin, eruboside B. After the derivatization with PNBC, the saponin derivative was chromatographed on a C8 column with a gradient elution of (A) 80% aqueous acetonitrile and (B) 100% acetonitrile. The detection limit of the developed method was 1 μg/g for the samples. The method was applied to the analysis of garlic and and garlic health food products available in Japan.


2004 ◽  
Vol 67 (1) ◽  
pp. 142-147 ◽  
Author(s):  
KYONG-SU KIM ◽  
HYE-YOUNG SEO ◽  
JEONG-MIN LEE ◽  
EUN-RYONG PARK ◽  
JUN-HYOUNG KIM ◽  
...  

We investigated the usefulness of hydrocarbons and 2-alkylcyclobutanones as markers for irradiated, dried shrimps. A method was developed to detect the irradiation of dried shrimps ( Penaeus aztecus) by identifying radiation-induced hydrocarbons and 2-alkylcyclobutanones extracted from dried shrimps, which were separated by Florisil column chromatography and identified by a method using gas chromatography/mass spectrometry. Radiation-induced hydrocarbons and 2-alkylcyclobutanones are formed from the fatty acids of the irradiated fats. The quantity of the hydrocarbons and 2-alkylcyclobutanones formed from some fatty acids is related to the composition of fatty acids in a sample. The concentrations of hydrocarbons and 2-alkylcyclobutanones increased with radiation dose. The major hydrocarbons in the irradiated, dried shrimps were 1-tetradecene and pentadecane from palmitic acid; small amounts of heptadecane and 1-hexadecene from stearic acid; and 8-heptadecene and 1,7-hexadecadiene from oleic acid. 2-(5′-Tetradecenyl)cyclobutanone, one of the 2-alkylcyclobutanones, was present at the highest concentration. The radiation-induced hydrocarbons and 2-alkylcyclobutanones were detected at radiation doses of 0.5 kGy and greater. These compounds were not detected in nonirradiated, dried shrimps.


2000 ◽  
Vol 63 (11) ◽  
pp. 1563-1569 ◽  
Author(s):  
HAE-JUNG LEE ◽  
MYUNG-WOO BYUN ◽  
KYONG-SU KIM

The method consists of the extraction of fat from perilla seeds, separation of hydrocarbons and 2-alkylcyclobutanones with florisil column chromatography, and identification of hydrocarbons and 2-alkylcyclobutanones by gas chromatography–mass spectroscopy (GC-MS). Concentrations of hydrocarbons and 2-alkylcyclobutanones increased with the irradiation dose. The major hydrocarbons in the irradiated perilla seeds were 8-heptadecene and 1,7-hexadecadiene from oleic acid and 6,9-heptadecadiene and 1,7,10-hexadecatriene from linoleic acid. One of the 2-alkylcyclobutanones, 2-(5′-tetradecenyl)cyclobutanone, was found in the highest concentration in the irradiated perilla seeds. Radiation-induced hydrocarbons in the perilla seeds were detected at doses of 0.5 kGy and higher, and radiation-induced 2-alkylcyclobutanones were detected at doses of 1 kGy and higher. These compounds were not detected in nonirradiated perilla seeds.


1989 ◽  
Vol 52 (2) ◽  
pp. 92-95 ◽  
Author(s):  
YASUHIDE TONOGAI ◽  
YUKARI HASEGAWA ◽  
YUMIKO NAKAMURA ◽  
SHIGERU FUJINO ◽  
YOSHIO ITO

A simple and rapid method for simultaneous determination of 10 kinds of organochlorine insecticides (ß-BHC, heptachlor, heptachlor epoxide, aldrin, dieldrin, endrin, p,p′-DDT, p,p′-DDE, p,p′-DDD, t-chlordane) in beef was established. The pesticides were extracted from samples with acetone hexane (3:1) mixture, and purified by Florisil column chromatography, then determined by use of a gas chromatograph equipped with an electron capture detector (ECD-GLC). Recoveries of the 10 pesticides added to beef at 0.02 ppm and 0.1 ppm were within the range of 63.9 - 89.0% and 76.8 - 90.5% by the proposed method, respectively. One hundred and twenty six samples of Australian beef received at the Osaka and Kobe quarantine stations from August to December in 1987 were analyzed, and only one sample was over the limit of dieldrin (+aldrin) referring to Japanese temporary tolerance.


1987 ◽  
Vol 70 (4) ◽  
pp. 740-745
Author(s):  
Ronald G. Luchtefeld

Abstract A method is described for determining substituted urea herbicides in foods. The residues are extracted from the product with methanol, and the food coextractives are removed by using solvent partitioning and Florisil column chromatography. The extract is analyzed using liquid chromatography with postcolumn photodegradation, chemical derivatization with orthophthalaldehyde, and spectrofluorometry. Recoveries were determined by spiking 8 different food products with 6 phenylureas—chlorbromuron, chloroxuron, diuron, fluometuron, linuron, and metobromuron—at 0.05 and 0.5 ppm. Three determinations were made at each level for each product. Average recovery at 0.05 ppm was 95% (with a standard deviation of 7.9%), and at 0.5 ppm, 98% (with a standard deviation of 6.9%).


1987 ◽  
Vol 70 (4) ◽  
pp. 740-745
Author(s):  
Ronald G Luchtefeld

Abstract A method is described for determining substituted urea herbicides in foods. The residues are extracted from the product with methanol, and the food coextractives are removed by using solvent partitioning and Florisil column chromatography. The extract is analyzed using liquid chromatography with postcolumn photodegradation, chemical derivatization with orthophthalaldehyde, and spectrofluorometry. Recoveries were determined by spiking 8 different food products with 6 phenylureas—chlorbromuron, chloroxuron, diuron, fluometuron, linuron, and metobromuron—at 0.05 and 0.5 ppm. Three determinations were made at each level for each product. Average recovery at 0.05 ppm was 95% (with a standard deviation of 7.9%), and at 0.5 ppm, 98% (with a standard deviation of 6.9%).


1986 ◽  
Vol 49 (11) ◽  
pp. 909-913 ◽  
Author(s):  
YASUHIDE TONOGAI ◽  
YOSHIO ITO ◽  
SHUNJIRO OGAWA ◽  
MASAHIRO IWAIDA

A simple and systematic procedure for determination of 1,2-dibromo-3-chloropropane (DBCP), 1,3-dichloropropene (DCP), chlorobutol (TCB) and seven related compounds in citrus fruits was established. Since these compounds have extremely high volatility, the distillation apparatus for volatile oil determination was used. These compounds were trapped into cyclohexane (more than 94.2–98.4% at spiking levels of 0.5–50 ppm) by this distillation. The distillate was purified by Florisil column chromatography. All compounds except TCB were eluted with n-hexane:ether(93:7) and TCB was eluted with ether. Each eluate was injected into an ECD-gas chromatograph directly for determination. Their recoveries from lemon, orange and grapefruit were within 91.5–98.6% at the spiking levels of 0.01–1 ppm.


1986 ◽  
Vol 69 (4) ◽  
pp. 586-591
Author(s):  
Martin P Yurawecz ◽  
Jo-Yun T Chen ◽  
Bartholomew J Puma

Abstract The cis- and trans-isomers of 1,1,2,3,4-pentachloro-4-[1-methylethoxy]-1,3-butadiene have been identified as contaminants in fish caught from the Mississippi River at St. Louis, MO, and as far as 150 miles south of that location. Up to 0.1 ppm of the cis-isomer and 0.8 ppm of the trans-isomer were determined by using a method based on the AOAC multiresidue method for detecting organochlorine and organophosphorus pesticides. In tests of the modified AOAC method on spiked fish, both isomers were quantitatively recovered (95-106%). A mixture of the cis- and trans-isomers was synthesized by reacting hexachlorobutadiene with sodium isopropoxide. Separation of the reaction products by Florisil column chromatography provided reference standards of the individual isomers for identification and quantitation of the residues. The stereospecificity of the synthesis reaction and the infrared and mass spectral data used to verify the structures of the products are discussed.


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