The fruits and flowers of Sambucus nigra (black elderberry) are used traditionally in culinary preparations while the leaves, flowers and fruits have been used in traditional medicine
for the treatment of common cold, fever, coughing, constipation, inflammatory conditions, as well as a diuretic and diaphoretic agent [1]. Numerous pharmacological
studies confirm the immunomodulatory, antioxidant, anti-inflammatory, anti-cancer and antimicrobial activities of S. nigra extracts. Polyphenols, such as phenolic acids, flavonoids and
anthocyanins are perhaps the most important bioactive compounds of black elderberry [2]. In our study, we examined the total phenolic content (using the
Folin-Ciocalteu method) and the in vitro antioxidant activity (by the DPPH assay) of hydromethanolic extracts from the leaves of organically and conventionally cultivated Greek S. nigra
plants. The leaf samples were also assessed by means of ICP-OES analysis for their content in trace elements. The total phenolic content of the leavesʼ extracts ranged from 84.984 ± 1.984 mg
GAE/L to 226.724 ± 2.755 mg GAE/L, while their antioxidant activity, calculated as % Radical Scavenging Activity (% RSA) was particularly high, from 78.065 ± 1.837% to 100.00 ± 0.884%.
Finally, the ICP-OES analysis showed that K was the most abundant macro-element, with concentrations fluctuating between 5.972 ± 0.057 mg/g and 10.053 ± 0.240 mg/g, followed by Ca
(3.062 ± 0.061 – 6.799 ± 0.036 mg/g), whereas Al (71.943 ± 2.928 – 363.647 ± 1.457 mg/g) and Fe (66.801 ± 4.392 – 342.641 ± 3.642 mg/g) were the micro-elements with the highest content.
