Characterization of leaves of non-traditional plant species with respect to micro-, macro-, and trace elements

The exploration of non-traditional fruit species is gaining attention due to their potential to contribute to food security, human health, and sustainable agriculture. Leaves of such species are often underutilized, despite being rich in minerals and bioactive compounds that may support nutritional and pharmacological applications. This study investigated the elemental composition of leaves from eleven non-traditional fruit species (Amelanchier alnifolia, Asimina triloba, Chaenomeles japonica, Cornus mas, Diospyros lotus, Hippophae rhamnoides, Mahonia aquifolium, Morus nigra, Pseudocydonia sinensis, Schisandra chinensis, Ziziphus jujuba) cultivated under uniform conditions at the M.M. Gryshko National Botanical Garden (Kyiv, Ukraine). A total of 18 elements were quantified in dried leaf material, including macroelements (K, P, Ca, Mg, S, Na), trace elements (Fe, Mn, Zn, Cu, Cr, Ni, Se), and potentially trace elements (Al, As, Cd, Hg, Pb). Potassium was the dominant macroelement in all species, with the highest concentration in Morus nigra (26,079.2 mg/kg DW). Distinct accumulators were identified: Schisandra chinensis (P: 4,138.2 mg/kg; Se: 0.29 mg/kg), Chaenomeles japonica (Ca: 27,981.6 mg/kg; Zn: 48.7 mg/kg; Se: 0.74 mg/kg), and Hippophae rhamnoides (Fe: 114.6 mg/kg; Mn: 82.4 mg/kg). Essential trace elements relevant for metabolic and antioxidant activity (Zn, Cu, Mn, Se) were consistently detected at physiologically significant levels. Trace elements (Cd, Hg, Pb, As) occurred at low concentrations, below international safety thresholds. Cluster analysis distinguished three groups of species with characteristic accumulation patterns. One group (Schisandra chinensis, Mahonia aquifolium, Hippophae rhamnoides) demonstrated particularly high mineral content and pharmacological potential. In conclusion, pronounced interspecific variability was revealed, with several species showing outstanding enrichment in valuable elements. These findings support the safe and targeted use of non-traditional fruit leaves as promising raw materials for functional foods, nutraceuticals, and phytopharmaceuticals.