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polarities was investigated by thin-layer chromatography (TLC)—densitometry in the presence and absence of selected metal ions. It was shown that both solvents and ion type have an effect on the degradation process that leads to the generation of some new products with R F values, which are different from R F values for active substance. It was found that acetone and methanol solutions are sensitive to ultraviolet-C (UV-C) radiation as well as acetone—water and methanol—water solutions for cefepime hydrochloride and cefuroxime axetil. The photostability of cefuroxime axetil after UV-C radiation in acetone solution has the strongest effect on photodegradation compared with the photodegradation carried out in methanol. The studied ions enhanced the degradation of cephalosporins in solutions. Fe(III) and Ni(II) ions exerted the strongest effect on photodegradation of cefepime hydrochloride in acetone compared with radiation carried out in the presence of Mn(II), Cu(II), Co(II), Fe(II), and also without these ions. In methanol solutions of cefepime hydrochloride, a stronger effect on photodegradation was observed by addition of Fe(II) ions. Cefuroxime axetil was more stable in the presence of Fe(II), Fe(III), and Ni(II) in all environments than cefepime hydrochloride. Degradation profiles were additionally compared by principal component analysis to explore the main trends in their shape change.

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The qualitative and quantitative study of the behavior of drugs in various samples, such as pharmaceutical preparations or biological materials, is a significant element from the basis of analysis in the fields of pharmaceutical testing, clinical research, and forensic analysis. A presented thin-layer chromatography (TLC)–densitometry method has been developed for the estimation of cefuroxime axetil and cefepime in human whole blood and urine. Analysis was performed on silica gel 60 F254 TLC plates with two various solvent mixtures as mobile phases. It is a rapid, sensitive, and accurate method for the analysis of drugs from a complex matrix which can be applied in clinical laboratories to monitor the chosen drugs in biological materials.

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Thin-layer chromatography (TLC) methods coupled with densitometric detection were employed in analyses for the presence of nonhallucinogenic indole compounds in methanol extracts from the garlic (Allium sativum L.) bulbs originating from China, Georgia, Spain, Mexico, and Poland, and from granulated garlic in the form of seasoning (commercial product). Four indole compounds for which the garlic bulbs were analyzed, were detected: 5-methyltryptamine, L-tryptophan, 5-hydroxy-L-tryptophan, and melatonin, the amounts of which ranged from 4.2 to 199.6 mg kg−1 dry weight. In contrast, only 3 indole compounds were found in the garlic bulbs from Spain: 5-methyltryptamine, L-tryptophan and melatonin (85.7, 120.1, and 9.6 mg kg−1 dry weight, respectively). The total amount of indole compounds in the extracts from the garlic bulbs from China was the highest (415.4 mg kg−1 dry weight), while the amounts in the others (from Georgia, Spain, Mexico, Poland) were similar and ranged from 215.4 to 283 mg kg−1 dry weight. The granular, freeze-dried garlic contained the lowest content of indole compounds, and their total amount was only 207 mg kg−1 dry weight.

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A study on the effect of oxidizing or reducing agents on the stability testing of piroxicam, tenoxicam, meloxicam, and isoxicam was performed. Detection of the formed oxidation and/or degradation products after reaction with factors such as iodine, potassium manganate( VII), hydrogen peroxide, and ascorbic acid was conducted by thin-layer chromatography (TLC)—densitometry technique. The reacting mixtures were also exposed to increasing temperatures. The chromatographic profiles showed the formation of several new peaks for all oxicams due to the presence of a number of degradation products formed in the presence of analyzed redox agents. The calculated kinetic parameters have confirmed the greatest stability of meloxicam and piroxicam and the smallest stability of isoxicam in the analyzed conditions. In the case of all the analyzed drugs, principal component analysis identified temperature as the main factor responsible for the speed of degradation and the shape of degradation profile.

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Acta Chromatographica
Authors:
Włodzimierz Opoka
,
Katarzyna Kała
,
Remigiusz Krężałek
,
Katarzyna Sułkowska-Ziaja
,
Anna Maślanka
, and
Bożena Muszyńska

Agaricus bisporus and Imleria in vitro cultures were cultivated on modified Oddoux medium, and Oddoux medium was enriched with serine or anthranilic acid. Serine or anthranilic acid was used at the concentrations of 0.1, 0.25, 0.5, and 0.75 g/L of medium. Determination of indole compounds in the obtained biomass was carried out using thin-layer chromatography (TLC) with densitometric detection. In every analyzed sample, presence of serine or anthranilic acid was studied. Comparison of the results obtained for the treatment and control samples allowed us to determine the optimum concentration of serine or anthranilic acid in the medium in order to obtain biomass with increased content of indole compounds. A. bisporus with addition of anthranilic acid or serine to the medium at the concentration of 0.5 g/L was the most beneficial. In the case of Imleria badia, anthranilic acid at the concentration of 0.5 g/L was the most optimal. This is the first report demonstrating the content of indole derivatives in biomass affected by their precursors (serine or anthranilic acid). The study indicates that modification of the medium can provide satisfactory results, and it is worth to search for its new, improved compositions.

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