Updated Organic Composition and Potential Therapeutic Properties of Different Varieties of Olive Leaves from Olea europaea

Plants (Basel). 2023 Feb 3;12(3):688. doi: 10.3390/plants12030688.

Abstract

Olea europaea L. folium merits further exploration of the potential of its substrates for therapeutic supplements. Quantitative and qualitative analyses were conducted on samples of Madural, Verdeal, and Cobrançosa elementary leaves and leaf sprouts (mamões) collected in the region of Valpaços, Portugal. Organic analysis assessed the moisture content, total carbohydrates, ash, protein, and fat contents, total phenolic content (TPC), vitamin E, and fatty acid (FA) profiles. Moisture content was determined through infrared hygrometry and TPC was determined by a spectrophotometric method. Concerning organic analysis, all leaf samples showed similar moisture content, though Cobrançosa's leaf sprouts and Verdeal's elementary leaves had slightly lower contents. Meanwhile, these cultivars also showed a higher TPC, α-tocopherol isomer, and fatty acid composition (FAC). FAC in all samples exhibited higher contents of PUFA and SFA than MUFA, with a predominance of linolenic and palmitic acids. Organic analyses of Cobrançosa's leaf sprouts and Verdeal's elementary leaf extracts allow for the prediction of adequate physiological properties regarding neuroinflammatory, neurobehavioral, metabolic, cardiovascular, osteo-degenerative, anti-ageing, pulmonary, and immunological defense disorders. These physiological changes observed in our preliminary in silico studies suggest an excellent nutraceutical, which should be borne in mind during severe pandemic situations.

Keywords: Olea europaea L. folium; fatty acids; intelligent bioactive compounds; nutraceutical potential; phenolic compounds; vitamin E.

Grants and funding

The authors acknowledge funding from Fundação para a Ciência e Tecnologia (FCT) through national funds/MCTES (Portugal) (UIDB/50006/2020). Diana Melo Ferreira is grateful to the Laboratório Associado para a Química Verde—Tecnologias e Processos Limpos—UIDB/50006/2020 that supports her, grant REQUIMTE 2019-57. This research was also supported by the project SYSTEMIC “an integrated approach to the challenge of sustainable food systems: adaptive and mitigatory strategies to address climate change and malnutrition” and the Knowledge Hub on Nutrition and Food Security, which has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS, and FACCE-JPI, launched in 2019 under the ERA-NET ERA-HDHL (no. 696295).