HPLC‐F analysis of melatonin and resveratrol isomers in wine using an SPE procedure

Abstract

An original analytical method has been developed for the determination of the antioxidants trans-resveratrol (t-RSV) and cis-resveratrol (c-RSV) and of melatonin (MLT) in red and white wine. The method is based on HPLC coupled to fluorescence detection. Separation was obtained by using a RP column (C8, 150 mm x 4.6 mm id, 5 mum) and a mobile phase composed of 79% aqueous phosphate buffer at pH 3.0 and 21% ACN. Fluorescence intensity was monitored at lambda = 386 nm while exciting at lambda = 298 nm, mirtazapine was used as the internal standard. A careful pretreatment of wine samples was developed, using SPE with C18 cartridges (100 mg, 1 mL). The calibration curves were linear over the following concentration ranges: 0.03-5.00 ng/mL for MLT, 3-500 ng/mL for t-RSV and 1-150 ng/mL for c-RSV. The LOD values were 0.01 ng/mL for MLT, 1 ng/mL for t-RSV and 0.3 ng/mL for c-RSV. Precision data, as well as extraction yield and sample purification results, were satisfactory. Thus, the method seems to be suitable for the analysis of MLT and resveratrol isomers in wine samples. Moreover, wine total polyphenol content and antioxidant activity were evaluated.

Impact of Saccharomyces cerevisiae Strains on Health-Promoting Compounds in Wine

“…These amounts were higher than values found by another study [42] carried out on wines after the fermentation of musts obtained from three grape varieties (Sangiovese, Albana and Trebbiano).…”

Voltammetric determination of melatonin using a graphene-based sensor in pharmaceutical products

“…3,4 Numerous analytical methods were reported for detection and quantification of melatonin, such as ultraviolet-visible (UV-vis) spectrophotometry, chemilumenescence, fluorometry, thin-layer chromatography, gas chromatography-mass spectrometry, and high-performance liquid chromatography. [5][6][7][8][9] Furthermore, melatonin is an antioxidant compound that can be analyzed with electrochemical methods. 10 Voltammetric and amperometric methods were applied for the determination of melatonin using carbon paste electrodes, carbon disk electrode, carbon fiber microdisk electrode, etc.…”

Concentrations and profiles of melatonin and serotonin in fruits and vegetables during ripening: A mini-review

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