ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Tannins analysis from different medicinal plants extracts using MALDI-TOF and MEKC

Alina Oana Matei, Florentina Gatea, Eugenia Dumitra Teodor, and Gabriel Lucian Radu

^aNational Institute for Biological Science, Splaiul Independentei 296, 060031, Bucharest, Romania

E-mail: gl_radu@chim.upb.ro

Abstract: The matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF) and micellar electrokinetic chromatography (MEKC) methods were used to identify and quantify five tannins, (+)-catechin, (–)-epigallocatechin, (–)-epigallocatechin gallate, (–)-epicatechin gallate and (–)-epicatechin, from aqueous, ethanolic and acetonic extracts of Calendula officinalis, Hypericum, perforatum, Galium verum and Origanum vulgare. The MALDI-TOF technique was used for screening tannins monomers and oligomers in plant extracts. The sandwich method and matrix 2,5-dihydroxybenzoic acid with a concentration of 10 mg mL^–1 in acetonitrile/ultrapure water/trifluoroacetic acid (20 : 80 : 0.1, vol.) were used. The electrophoretic method developed for the separation and quantification of 5 catechins in 15 min exhibited good efficiency and precision, low limits of detection (0.0032–0.0153 μg mL^–1) and quantification (0.0096–0.0466 μg mL^–1). The correlation coefficients (R²) exceeded 0.9986 and the recovery values ranged between 94.25 % and 102.50 %. The present work provides new information on some of the less studied compounds present in plants frequently used in traditional medicine.

Keywords: tannin – plant extract – MALDI-TOF – MEKC

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0222

Chemical Papers 70 (4) 515–522 (2016)