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Phenolic contents, antioxidant and antimicrobial activities were determined by two samples from summer (June) and winter (December) seasons of Ligularia fischeri var. spiciformis Nakai. A total of 24 phenolic compounds were identified by ultra-performance liquid chromatography (UPLC) analysis. Myricetin (1964.35 and 1829.12 μg/g) was the most dominant flavonol compared to quercetin and kaempferol. Salicylic acid (222.80 and 215.25 μg/g) was the most important phenolic compound compared to pyrogallol, caffeic acid, gentisic acid, o-coumaric acid, gallic acid, protocatechuic acid and ferulic acid in summer (June) and winter (December) seasons. Phenolic contents and antioxidant capacities were estimated for the various solvent extracts (petroleum ether, butanol, ethyl acetate, methanol and water). Ethyl acetate extract exhibited the highest phenolic (332.64 and 299.44 mg/g gallic acid equivalent) and flavonoid contents (5.72 and 5.29 mg/g quercetin equivalent) and also the strongest antioxidant activity in summer and winter seasons. Due to these metabolic variations, the antioxidant and antimicrobial activities were increased with summer seasons compared to winter seasons. Our study shows that the samples collected in June had higher phenolic compounds, stronger antioxidative and antimicrobial activity than the samples of L. fischeri leaf extracts collected in December.

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A simple, selective, and sensitive thin-layer chromatographic—densitometric method has been developed for the determination of sulfasalazine besides its possible impurities in pharmaceutical preparations. The mobile phase was composed of ethyl acetate—methanol—ammonia 25% 10:7:3 (υ/υ/υ), and the stationary phase was aluminum plates precoated with silica gel 60 F254 that enabled to obtain well resolved peaks of sulfasalazine and its impurities. The developed chromatograms were analyzed densitometrically at λ = 360 nm. R F values and ultraviolet (UV) spectra were used to identify the compounds. The developed method is highly sensitive (limit of detection [LOD] = 17.11 ng spot−1, limit of quantitation [LOQ] = 51.84 ng spot−1), precise (relative standard deviation [RSD] = 1.43%–4.28%), and accurate (RSD = 1.64%–4.27%). The linearity of the method was checked within the range 20–120 ng spot−1. The method was successfully applied for the determination of sulfasalazine in pharmaceutical preparations besides its impurities. The structures of impurities present in the standard substance and in pharmaceutical preparations were established by ultra-performance liquid chromatography—tandem mass spectrometry (UPLC—MS/MS) technique.

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. [17]. M. Swartz , HPLC to UPLC method migration, An overview of key considerations and available tools, 2007 Waters Corporation , http://wwwwaterscom/webassets/cms/library/docs/720002064enpdf

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] A. Vijaya Bhaskar , N. Reddy , G. Venugopal , G. Reddy , V. Madhavi , A selective and sensitive UPLC-MS/MS approach for trace level quantification of four potential genotoxic impurities in zolmitriptan drug

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sensitivity and selectivity of these analyses, new methodologies (e.g., LC coupled with MS and tandem MS) have been developed [ 12 , 13 ]. In the present study, an ultra-performance liquid chromatography (UPLC)–tandem MS (MS/MS) was applied to study the

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, hydrochlorothiazide and all known related compounds when in the finished product dosage form using HPLC and UPLC , University of North Carolina , Wilmington, NC , 2011 . [14] S

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include Liquid Chromatography Tandem Mass Spectroscopy (LC-MS), Ultra-Performance Liquid Chromatography (UPLC). There are numerous articles that suggest how to find out amount of HCTZ in plasma, urine, and serum. Antihypertensive patients can benefit from

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chromatography tandem mass spectrometry (thermo electric TSQ Quantum ultra, USA), on-line cleanup column Cyclone-P (0.8 × 50 mm), HPLC Columns, ACQUITY UPLC BEH C 18 (2.1 mm × 100 mm, 1.7 μm), homogenizer (ULTRA-TURRAX Tube Drive, Germany), high

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phenolamides in barley (Hordeum vulgare) and beer by UPLC-QTOF-MS. J. Cereal Sci., 2014, 60 (3), 645–652. 31 Győry, H.: The “collected book of remedies for removing the

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