Health-protecting Properties of Olive Leaves (Olea europaea L.) via Antioxidant Profile and Phenolic Composition – Abstract

Journal of Environmental and Agricultural Sciences (JEAS). Akbaba, 2023. 25(3&4): 11-21.

Open Access – Research Article

Health-Protecting Properties of Olive Leaves (Olea europaea L.) via Antioxidant Profile and Phenolic Composition
Emel Akbaba
Department of Medical Biology, Faculty of Medicine, Kirikkale University, 71450, Kirikkale, Turkiye

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Abstract: Olive (Olea europaea L.) leaves are the major by-product of the olive oil industry, containing a variety of bioactive chemicals with significant potential health benefits. The major components of olives that are responsible for their therapeutic properties are phenolic compounds. An experiment was designed to determine phenolic and flavonoid contents, and antioxidant activity of methanolic extracts of olive leaves obtained using two techniques: maceration and microwave-assisted extraction. The antioxidant activities of the extracts were determined via ferric-reducing antioxidant power and phenanthroline-metal chelating capacity assays. The extract obtained via maceration yielded 37 mg g^-1 of total phenolics, 16 mg g^-1 total of flavonoids, 50 mg g^-1 ferric-reducing antioxidant biomolecules, and 140 mg g^-1 of phenanthroline metal chelating phytochemicals. However, microwave-assisted extraction yielded 38 mg g^-1 of total phenolics, 21 mg g^-1 of total flavonoids, 52 mg g^-1 of ferric-reducing antioxidant biomolecules, and 142 mg g^-1 of phenanthroline-metal chelating phytochemicals. In comparison to maceration, the microwave-assisted extraction method produced slightly higher quantities of bioactive compounds in a relatively short time, while using less solvent. This study showed that olive leaves have great potential for bioactive molecules and antioxidant profiles. This study also reports the importance of taking advantage of olive leaves, which are byproducts of factories and are generally considered waste. Therefore, olive leaves are highly recommended in the food industry as natural antioxidants rather than synthetic antioxidants, which can cause a variety of health problems.

Keywords: Microwave-assisted extraction, phenolic compounds, Olea europaea, antioxidant potential, olive.
*Corresponding author: Emel Akbaba, eakbaba@kku.edu.tr

Cite this article as:

Akbaba, E. 2023. Health-protecting properties of olive leaves (Olea europaea L.) via antioxidant profile and phenolic composition. Journal of Environmental & Agricultural Sciences. 25(3&4): 11-21. [Abstract] [View Full-Text] [Citations]

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Copyright © Akbaba, 2023  This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium provided the original author and source are appropriately cited and credited.

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