Extraction of valuable lipophilic compounds from Vincetoxicum species

Swallow-wort (Vincetoxicum) is an herbaceous, perennial, climbing plant native to Europe, North America and Asia. Swallow-wort have diuretic and laxative properties and a powder made from the roots is said to accelerate wound healing. It must be stressed that swallow-wort is a poisonous plant, which in large doses can affect the nervous, vascular and cardiac systems. However, there is very little detailed scientific information on these plants. The aim of this work was to determine chemical composition of three Vincetoxicum species leaves; to evaluate the yields obtained by supercritical fluid extraction with carbon dioxide (SFE-CO2) and traditional Soxhlet extraction, characterize the extracts and evaluate their antioxidant capacity. V. hirundinaria, V. nigrum and V. luteum were defatted by SFE-CO2. The lipophilic extracts were analsed by different methods. Triacylglycerols (TAGs) were analysed by ultra-performance liquid chromatography (UPLC), while the total chlorophyll and carotenoid contents were measured by spectrophotometric method. Antioxidant activity was evaluated by using different in vitro antioxidant capacity assays: the DDPH assay and the Oxygen Radical Absorbance Capacity (ORAC) assay. Total phenol content was measured by Folin-Ciocalteu method. The yields of lipophilic fractions recovered by SFE-CO2 were 1.3–1.7%, while those obtained by Soxhlet varied from 1.7 to 2%. Linoleic, linolenic, oleic and palmitic acids were major fatty acids in the extracted triacylglycerols. The concentration of carotenoids and chlorophylls varied between different species. The extracts obtained by different extraction methods were characterized by their antioxidant potential. It can be concluded that extraction by supercritical fluid extraction with carbon dioxide can extract valuable bioactive compounds from leaves of different Vincetoxicum species.