Microwave-Assisted Extraction of Major Bioactive Phenolic Compounds from Olive Industrial Byproducts using Natural Deep Eutectic Solvents

Abstract

Developing environmentally friendly extraction techniques for natural products is an interesting research issue in the interdisciplinary fields of technology, biology, and applied chemistry. This study applied a novel and sustainable approach to extract and derivatize valuable bioactive phenolic compounds from olive oil industry by-products. Microwave-assisted extraction (MAE) was used to investigate the extraction of phenolic components from olive oil industry by-products by several naturally nontoxic, ecologically friendly Deep eutectic solvents (DESs) and their mixtures with water. The quantification of phenolic compounds was established by high-performance liquid chromatography (HPLC) analysis. The effects of the solvent type were studied and evaluated for the oleuropein, demethyloleuro-pein, oleacine(3,4-DHPEA-EDA), and hytrosol content in olive oil industry by-products. Among all the solvents studied, the findings of this study suggest that glycerol-based NADES-2 is an excellent solvent in terms of its effectiveness in extracting phenolic compounds, especially oleuropein after 10 minutes. Generally, among all polyphenolic compounds, the best extraction result with NADESs (with and without water) was recorded for dimethyloleuropine. Furthermore, the process of extraction is simple, accurate, and safe. Since the solvents used are obtained from natural sources, it satisfies most of the requirements needed to be considered a sustainable method with several advantages of microwave-assisted extraction (MAE), including shorter extraction times, decreased solvent consumption, and more efficient extraction capacity

The work was carried out with the support of the CREA-Research Centre (Rende, CS, Italy)

Please cite this article as:

Rahman H.S., Nardi M., Ahmed F.M. Microwave-assisted extraction of major bioactive phenolic compounds from olive industrial byproducts using natural deep eutectic solvents. Herald of the Bauman Moscow State Technical University, Series Natural Sciences, 2025, no. 2 (119), pp. 107--121. EDN: LEHSAA

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