Phytochemical analysis of elderberry (Sambucus nigra): focus on non-anthocyanin constituents

Elderberry (Sambucus nigra) has received considerable attention for its health-promoting properties, particularly during the COVID-19 pandemic, when its products became one of the top-selling herbal supplements in the United States. While the anthocyanin profile of elderberry is well characterised, comprehensive studies of its non-anthocyanin constituents are underexplored. An in-depth phytochemical investigation of dried elderberry fruits, focusing on non-anthocyanin constituents, led to the discovery of a novel iridoid glycoside named elderberoside (1). Additionally, ten known metabolites were isolated, including an iridoid (2), an alkaloid (3), and eight flavonoids (4-11). Structural elucidation of these compounds was achieved through detailed one-dimensional (1D) and two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy and confirmed by mass spectrometry.