Secondary volatile metabolite content of two Echinacea species in two subsequent years in Rize, Türkiye

The present research aimed to determine the secondary volatile metabolite composition of E. angustifolia and E. purpurea under the ecological conditions of Pazar/Rize over two years. Both species were investigated over two consecutive years and their secondary volatile metabolite profiles of the aboveground plant parts (totally stems, leaves, flowers, and inflorescences of 40 plants per plot) were determined using GC-MS analysis supported with SPME in triplicate. Remarkable variation could be detected between the two species. Major components detected in E. angustifolia in both years (2015–2016) were p Cymene (35.24% and 21.36%), β –Pinene (23.32% and 16.74%) and α – Pinene (11.23% and 8.09). On the other hand, main components obtained in E. purpurea in both years were Caryophyllene oxide (12.61 and 15.13%), Germacrene D (8.15% and 15.12%) and Allo-Aromadendrene (15.01% and 0.00%). The combined results indicated that E. angustifolia and E. purpurea cultivated in Rize exhibited secondary volatile metabolite compositions that differed in concentration from those previously reported in the literature. Several important secondary volatile metabolite components were detected in E. angustifolia and E. purpurea during both years of the study.