ABSTRACT
The metal-organic framework [(La0.9 Sm0.1 )2 (DPA)3 (H2 O)3 ]∞ was synthetized and characterized by X-ray diffractometry, differential thermogravimetric analysis, and infrared spectroscopy. The material was tested for the development and validation of a matrix solid-phase dispersion procedure for extraction of atrazine, bifenthrin, bromuconazole, clofentezine, fenbuconazole, flumetralin, procymidone, and pirimicarb, from peppers, with analysis using gas chromatography with mass spectrometry in the selected ion monitoring mode. The method developed was linear over the range tested (50.0-1000.0 µg/kg for procymidone and 200.0-1000.0 µg/kg for all other pesticides), with correlation coefficients ranging from 0.9930 to 0.9992. Experiments were carried out at 250.0, 500.0, and 1000.0 µg/kg fortification levels, and resulted in recoveries in the range of 52.7-135.0%, with coefficient of variation values between 5.2 and 5.4%, respectively, for [(La0.9 Sm0.1 )2 (DPA)3 (H2 O)3 ]∞ sorbent. Detection and quantification limits ranged from 16.0 to 67.0 µg/kg and from 50.0 to 200.0 µg/kg, respectively, for the different pesticides studied. The results were compared with literature data. The developed and validated method was applied to real samples. The analysis detected the presence of residues of pesticides procymidone, fenbuconazole, flumetralin, clofentezine, atrazine, and bifenthrin.
Subject(s)
Capsicum/chemistry , Lanthanoid Series Elements/chemistry , Metal-Organic Frameworks/chemistry , Pesticides/isolation & purification , Solid Phase Extraction , Aniline Compounds/chemistry , Aniline Compounds/isolation & purification , Atrazine/chemistry , Atrazine/isolation & purification , Bridged Bicyclo Compounds/chemistry , Bridged Bicyclo Compounds/isolation & purification , Carbamates/chemistry , Carbamates/isolation & purification , Chlorobenzenes/chemistry , Chlorobenzenes/isolation & purification , Furans/chemistry , Furans/isolation & purification , Gas Chromatography-Mass Spectrometry , Metal-Organic Frameworks/chemical synthesis , Nitriles/chemistry , Nitriles/isolation & purification , Pesticides/chemistry , Pyrethrins/chemistry , Pyrethrins/isolation & purification , Pyrimidines/chemistry , Pyrimidines/isolation & purification , Triazoles/chemistry , Triazoles/isolation & purificationABSTRACT
The alkaloids lycorine, 1-O-acetyllycorine and ismine were isolated from the basic dichloromethane-soluble fraction of Crinum x powellii "Albu m" bulbs. The alkaloid structures were established by physical and spectroscopic analyses, including 1D NMR techniques and GC-MS analysis. The three alkaloids are reported for the first time for this hybrid. Additionally, the three alkaloids isolated were tested against a mechanism-based bioassay utilizing genetically engineered mutants of the yeast Saccharomyces cerevisiae strains RAD+, RAD52Y and RS321 where lycorine was the only alkaloid that displayed moderate topoisomerase I inhibitory activity.
Subject(s)
Alkaloids/isolation & purification , Crinum/chemistry , Enzyme Inhibitors/isolation & purification , Plant Extracts/chemistry , Topoisomerase Inhibitors , Alkaloids/chemistry , Alkaloids/pharmacology , Amaryllidaceae Alkaloids/chemistry , Amaryllidaceae Alkaloids/isolation & purification , Amaryllidaceae Alkaloids/pharmacology , Aniline Compounds/chemistry , Aniline Compounds/isolation & purification , Aniline Compounds/pharmacology , Chromatography, Thin Layer , Enzyme Inhibitors/pharmacology , Methanol , Mutagenesis , Phenanthridines/chemistry , Phenanthridines/isolation & purification , Phenanthridines/pharmacology , Plant Extracts/isolation & purification , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/geneticsABSTRACT
Reversed phases for high-performance liquid chromatography (RP-HPLC) were obtained by thermal immobilization of polysiloxanes having different length chains (C1, C8 and C14) onto HPLC silica particles. The importance both of percent loading of the stationary phase promoted by each immobilization procedure and of the length of the lateral chain of the polymer on the chromatographic performances of the phases obtained is compared and discussed.