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.

Olea europaea L. folium has been studied for its potential nutraceutical properties. Quantitative and qualitative analyses were conducted on samples of Madural, Verdeal, and Cobrançosa elementary leaves and leave sprouts (mamões) collected in the region of Valpaços, Portugal. Mineral analysis determined the measurements of the levels of several macro- and micro-elements based on ICP-MS techniques. The inorganic analysis in this work allowed us to propose olive leaf extract (OLE) from different cultivars as a viable and affordable source of mineral substrates to address disorders related to essential elements such as Na, K, Mg, Ca, Mn, Fe, and Cu deficiencies. Given the importance of the research on novel therapies, finding a suitable substrate for extracting quality amounts of mineral is a priority. The physiological influence of enzymes dependent on minerals with regard to neuroinflammatory and neurobehavioral, metabolic, cardiovascular, osteodegenerative, anti-aging, pulmonary, and immunological defense disorders might dictate the importance of further research for designing supplementation based on the nutraceutical potential of OLE of these cultivars predominant in the northern region of Portugal.