The higher the better? Differences in phenolics and cyanogenic glycosides in Sambucus nigra leaves, flowers and berries from different altitudes.

BACKGROUND: Elderberry (Sambucus nigra L.) possesses high antioxidant activity and has been used to treat numerous medicinal disorders. In addition to their antioxidant properties, elderberry parts accumulate toxic cyanogenic glycosides (CGG). It has been proven that altitude influences the biosynthesis of many secondary metabolites. In the present study we investigated the change of phenolics and CGG in elder leaves, flowers, and berries induced by different altitudes and locations.

RESULTS: The data indicate that the accumulation of CGG and phenolics is affected by the altitude of the growing site. An increase of anthocyanin content was recorded in elder berries collected at higher elevations in both locations. Fruit collected at the foothills of location 2 contained 3343 µg g-1 anthocyanins as opposed to fruit from the hilltop, which contained 7729 µg g-1 . Elder berries contained the lowest levels of harmful CGG compared to other analysed plant parts. However, more cyanogenic glycosides were always present in plant parts collected at the hilltop. Accordingly, berries accumulated 0.11 µg g-1 CGG at the foothills and 0.59 µg g-1 CGG at the hilltop.

CONCLUSION: Elder berries and flowers collected at the foothill were characterised by the lowest levels of both beneficial (phenolics) and harmful compounds (CGG) and are suitable for moderate consumption. © 2016 Society of Chemical Industry.