Application of liquid phase and microwave extraction for the determination of multi-component phenolic pattern in different Galium species (Galium verum, Galium purpureum, Galium rivale, Galium pseudoaristatum) and commercial phytopharmaceuticals

Recently, using of herbal medicines for the prevention and preservation of health became a trend in modern medicine due to such benefits as safety, accessibility, efficacy with a wide range of therapeutic action and low costs [1]. Galium is a well-known genus gathering many medicinal representatives, which are rich sources of phenolic compounds [2,3]. The aim of the current study is to develop liquid phase and microwave extractions (MAE) procedures in order to establish multi-component phenolic pattern of Galium verum, Galim purpureum, Galium rivale, Galium pseudoaristatum and analyze twelve commercially available phytopharmaceuticals of Galium verum using HPLC- PDA. Dispersive liquid–liquid microextraction (DLLME) in NaCl and natural deep eutectic solvent (NADES) medium and ultrasound-assisted DLLME in β-cyclodextrine medium were optimized. The optimal DLLME conditions were found to be: 10 mg of the sample, 10% NaCl or 15% NADES, extraction solvent – 400 μL of ethyl acetate, dispersive solvent – 300 μL of ethanol, vortex time – 30 s, extraction time – 1 min, centrifugation at 12 000 rpm for 5 min. In the case of UA-DLLME, 5 min of ultrasonication is required. The developed microextraction procedures were applied for analysis of real samples and compared with results of MAE. Acknowledgments Authors acknowledge for financial support MIUR ex 60%, University “G. d’Annunzio” of Chieti – Pescara, Chieti, Italy, and Scientific Grant Agency of the MESRS of the Slovak Republic (VEGA 1/0010/15). References: 1. Efferth, T. (2011) Perspectives for Globalized Natural Medicines. CJNM 9: 1–6. 2. Vlase, L., Mocan, A., Hanganu, D., Benedec, D., Gheldiu, A., Crişan, G. (2014) Comparative study of polyphenolic content, antioxidant and antimicrobial activity of four Galium species (Rubiaceae). Dig J. Nanomater. Bios. 9: 1085–1094. 3. Zengin G., Menghini L., Malatesta L., De Luca E., Bellagamba G., Uysal S., Aktumsek A., Locatelli M. (2016) Comparative study of biological activities and multicomponent pattern of two wild Turkish species: Asphodeline anatolica and Potentilla speciosa, J. Enzyme Inhib. Med. Chem. 31: 203–208.