Determination of Linuron and Its Known and/or Suspected Metabolites in Crop Materials

Abstract Linuron and its known and/or suspected metabolites are extracted from crops with acetone. The acetone is evaporated, and the aqueous residue containing precipitated plant materials and linuron and metabolites is extracted several times with hexane to remove linuron and any 3,4-dichloroaniline, a metabolite. The 3,4-dichloroaniline is separated from the linuron by HC1 extraction. Other possible metabolites, 3-(3,4- dichlorophenyl)-l-methoxy urea, 3-(3,4-dichlorophenyl)- l-methyl urea, and 3-(3,4-dichlorophenyl) urea, remain in the aqueous phase which is made basic with ammonium hydroxide. These metabolites are extracted into hexane and identified by thin layer chromatography. Linuron and metabolites other than 3,4-dichloroaniline can be determined colorimetrically after acid hydrolysis to the aniline, followed by a diazotization reaction and coupling with iV-(l-naphthyl) ethylenediamine. Levels as low as 0.02 ppm linuron can be detected. Recoveries of 98.9% were found. Bound linuron can be determined by alkaline hydrolysis or by enzymatic digestion of crop material which frees the undegraded bound linuron

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Quantitative Determination of Triterpenes from Amphiptherygium adstringens by Liquid Chromatography and Thin-Layer Chromatography and Morphological Analysis of Cuachalalate Preparations

Journal of AOAC International ◽

10.1093/jaoac/89.1.1 ◽

2006 ◽

Vol 89 (1) ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Andrés Navarrete ◽

Bharathi Avula ◽

Vaishali C Joshi ◽

Xiuhong Ji ◽

Paul Hersh ◽

...

Keyword(s):

Thin Layer ◽

Thin Layer Chromatography ◽

High Performance ◽

Limit Of Detection ◽

Gastric Ulcers ◽

Array Detector ◽

Plant Materials ◽

Relative Standard ◽

Layer Chromatography

Abstract Amphiptherygium adstringens (Anacardiaceae/Julianaceae), local name cuachalalate, is used in folk medicine for the treatment of cholelithiasis, fevers, fresh wounds, hypercholesterolemia, gastritis, gastric ulcers, and cancer of the gastrointestinal tract. The development of column high-performance liquid chromatographyphotodiode array detector (LC-PDA) and high-performance thin-layer chromatography (HPTLC)densitometry methods for the determination of masticadienonic acid and 3-hydroxymasticadienonic acid in cuachalalate preparations is described in this paper. Good separation of the compounds could be achieved by both methods. Either might be preparable depending on the requirements. The LC separation was performed on a Phenomenex Synergi MAX-RP 80A reversed-phase column operated at 40C with detection at 215 nm. The plant materials were extracted with methanol by sonication. The triterpenes present in the plant material and commercial extracts were separated with an acetonitrilewater reagent alcohol isocratic system. The limit of detection was 0.10.2 g/mL. The relative standard deviation values for the determination of triterpenes in plant extracts were less than 1.00%. This is the first report of an analytical method developed for the quantitative analysis of triterpenes from Amphiptherygium adstringens by LC-PDA and HPTLC. The stem bark showed higher amounts of triterpenes, and low amounts in root and stem root. The microscopic description of the crude drug of cuachalalate was also provided.

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DETERMINATION OF SIMPLE SUGARS IN MEDICINAL PLANT MATERIALS BY THE METHOD OF HIGH-PERFORMANCE THIN-LAYER CHROMATOGRAPHY (FOR EXAMPLE, THE FRUITS OF SEA BUCKTHORN L. AND NETTLE LEAVES L.)

chemistry of plant raw material ◽

10.14258/jcprm.2020015122 ◽

2020 ◽

pp. 215-222

Author(s):

Ol'ga Valer'yevna Trineeva ◽

Aleksey Ivanovich Slivkin

Keyword(s):

Medicinal Plant ◽

Thin Layer ◽

Thin Layer Chromatography ◽

High Performance ◽

Raw Materials ◽

Sea Buckthorn ◽

Standard Samples ◽

Plant Materials ◽

Layer Chromatography

An analysis of the literature over the past 20 years has shown that when controlling the quality of drugs containing monosaccharides, as well as studying the composition of simple sugars in polysaccharide complexes of medicinal plants and not only, preference is given to physicochemical methods, as the most express, sensitive and informative. No means have been found in the scientific literature to identify and quantify simultaneously various monosaccharides by high performance thin layer chromatography (HPTLC). An economical and rapid method has been developed for the identification and quantitative determination of simple reducing sugars (by the example of glucose, rhamnose and xylose) by the HPTLC method. The optimal conditions for their chromatography in a thin layer of sorbent with a quantitative interpretation of HPTLC data on a personal computer were experimentally selected and theoretically substantiated. In a detailed study of the influence of the polarity of the system on the value of Rf, the intervals of values of the polarity of the eluent were chosen, in which these dependences become linear. Using the proposed dependencies, you can select different systems for the separation of monosaccharides in a thin layer of sorbent, so that the value of Rf fit into the optimal values. The proposed method was tested on medicinal plant raw materials of nettle dioica and sea buckthorn fruits of various conservation methods. Zones of simple sugars of characteristic color were found on the chromatograms of extracts from the studied raw materials, among which glucose, xylose and rhamnose were identified by the characteristic value of Rf values in comparison with reliable standard samples. The technique can be used in quality control of substances, single-component and complex preparations, plant objects, dietary supplements, premixes and products of the food industry.

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