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Introduction Phenol is an organic compound of an anthropogenic origin, which is widely used in phenolic resins and plywood adhesives among others, and is also found in petroleum products, such as coal tar and creosote [ 1

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Introduction: In patients with chronic kidney disease (CKD), uremic toxins accumulate in blood and cannot be excreted with urine. Accumulation of these toxins has negative effects on many body functions. Because of the importance of these toxins, we developed and validated a simple, sensitive, accurate, and precise method for the determination of two main uremic toxins: phenol and p-cresol in human urine. Materials and methods: Separation of these analytes in urine samples was achieved by reverse-phase high-performance liquid chromatography (RP-HPLC) with a C18 column at 35 °C using the mobile phase of methanol–water (65:35) at a flow rate of 1.4 mL min−1. Fluorimetric detection was used at 284 nm for excitation and 310 nm for emission. Results: The method is linear over the range of 1.5–35 ng mL−1 and 1–45 ng mL−1 for phenol and p-cresol, respectively. The method was applied to urine samples from 10 healthy subjects and 10 chronic kidney disease patients. Conclusions: This assay appears to be useful in routine analysis of clinical samples for simultaneous determination of phenol and p-cresol levels in urine.

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Acta Chromatographica
Authors: Milica Atanacković Krstonošić, Jelena Cvejić Hogervorst, Mira Mikulić, and Ljiljana Gojković-Bukarica

1. Introduction Phenolic compounds are widely present among natural products, and they can express different beneficial biological activities. Some of them include antioxidant, cardioprotective, anticancer, anti

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fruit juices [ 8 , 10 ]. Due to reported anticarcinogenic properties of some flavonoids, demand for fruits with anthocyanidin and anthocyanin content has been increasing [ 11 ]. Despite their low content in fruits and vegetables, phenolic

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Introduction Phenolic compounds have began to attract the interest of researchers, because they show promise of being powerful antioxidants that can protect the human body from free radicals, the formation of which is

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anatomical–functional damage to our bodies detected with ageing. Ingredients that contain a phenolic group play a significant role in cosmetics, pharmaceutical products and food, to delay and inhibit cell ageing. Various techniques of analysis have been made

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Commelina benghalensis (Commelinaceae) is widely used as traditional and folklore medicine in India. In the present study, a reverse-phase high-performance liquid chromatography—photodiode array detection (RP-HPLC—PDA) method was developed for the separation, identification, and quantification of bioactive phenolics. Antioxidant potential was also accessed to validate the presence of identified markers. Method was developed on C18 column with 1% formic acid (in water) and acetonitrile as solvent system, and data acquisitions were achieved at wavelength of 285 nm. The developed method was also validated for accuracy, precision, robustness, limit of detection and quantification (LOD and LOQ), repeatability, and recovery according to International Conference on Harmonization (ICH) guidelines. In this method, five phenolics, viz., protocatechuic acid (0.033%), vanillic acid (0.262%), ferulic acid (0.365%), apigenin (0.126%), and kaempferol (0.544%), were quantified in linearity range of 0.2–1.0 μg with correlation coefficient of more than 0.9949. Relative standard deviation (RSD) (%), LOD, LOQ, and recovery (%) are within the acceptable limit. Besides that, methanolic extract shows the inhibition (%) range from 24.45 to 68.75% at 0.02–0.12 mg mL−1. IC50 of extract was observed at 46.75 μg mL−1, suggesting the promising activity in methanol extract. Hence, the proposed method for simultaneous quantification of five bioactive phenolics in the tuber of C. benghalensis using HPLC–PDA detection under the specified conditions is specific and accurate, and validation proves its selectivity and reproducibility.

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The rhizome of Sparganium stoloniferum Buch.-Ham has been used as a traditional Chinese folk medicine for thousands of years. Phenolic compounds are the main bioactive ingredients of the plant. In order to determine the content of phenolic compounds from different major cultivations, a reliable method has been developed using ultra-high performance liquid chromatography coupled with a triple quadrupole electrospray tandem mass spectrometry. Seven compounds, including rutin, kaempferol, p-hydroxybenzaldehyde, formononetin, ferulic acid, vanillic acid, and p-coumaric acid, were simultaneously measured in 10 min. The established approach was fully validated in terms of linearity, sensitivity, precision, repeatability as well as recovery, and successfully applied to determine seven phenolic compounds of Rhizoma Sparganii. This study may be helpful in the quality control of Rhizoma Sparganii and can offer technical support for the pharmacological and clinical study of related drugs.

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Progress in Agricultural Engineering Sciences
Authors: Szilvia Bánvölgyi, Eszter Dusza, Fiina K. Namukwambi, István Kiss, Éva Stefanovits-Bányai, and Gyula Vatai

Introduction Nile et al. (2013), Lafka et al. (2007), and Spigno et al. (2007) declared that grapes are among the fruits that have the highest content of phenolic compounds. Ignat et al. (2011), and Vatai et al. (2009) found that natural phenols

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A highly scalable and efficient flow-system has been developed to perform the catalyzed acetylation of alcohols and phenols, such as salicylic acid, at room temperature in excellent yield. The volumetric throughput and the amount of product can be increased simply by increasing the diameter of a versatile catalytic 12-tungstosilicic acid-supported, silica monolith can be used to increase the quantity of product produced without having to changeing the optimal operatingreaction conditions.

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