Novel lactic acid-based natural deep eutectic solvents: Efficiency in the ultrasound-assisted extraction of antioxidant polyphenols from common native Greek medicinal plants

作者：Bakirtzi, Christina; Triantafyllidou, Katerina; Makris, Dimitris P.^*

来源：Journal of Applied Research on Medicinal and Aromatic Plants, 2016, 3(3): 120-127.

DOI：10.1016/j.jarmap.2016.03.003

• Antioxidants
• NADES
• Medicinal plants
• Polyphenols
• Ultrasound-assisted extraction

Selected native Greek medicinal plants, including dittany, fennel, marjoram, mint and sage, were used to test the efficiency of some novel lactic acid-based natural deep eutectic solvents (NADES) to extract polyphenolic compounds. Extractions were performed under ultrasonication and the eutectic mixtures, tested as 80% (v/v) aqueous solutions, were lactic acid:choline chloride, lactic acid:sodium acetate, lactic acid:ammonium acetate and lactic acid:glycine:water, with corresponding molar ratios of 3:1, 3:1, 3:1 and 3:1:3. The three latter NADES are reported for the first time. Water and 60% (v/v) aqueous ethanol were also used as control solvents. The results obtained evidenced that lactic acid:glycine:water exhibited high efficiency, but in some instances lactic acid:sodium acetate and lactic acid:ammonium acetate were equally efficient. The data also suggested that extracts with high polyphenol concentration may also possess higher antiradical activity and reducing power. The NADES tested are non-toxic, renewable and exceptionally efficient solvents for polyphenol recovery from medicinal plants. The findings of this study were interpreted on the ground of assumptions regarding the polarity of the NADES tested.

• 出版日期2016-9