RESUMEN
Aerial parts and roots of Echinacea purpurea were harvested consecutively in order to find the best strategy for harvest of both types of plant material for an optimal content of bioactive alkamides and caffeic acid derivatives. Four caffeic acid derivatives and 15 alkamides were identified and quantified. The aerial parts were harvested in bud, bloom, and wilting stage and the roots were harvested 1 week, 1 month, and 3 months after each harvest of aerial parts. The highest yield per area of both alkamides and caffeic acid derivatives is achieved when the aerial parts are harvested late (wilting stage). To obtain an optimal content of alkamides and caffeic acid derivatives it is not recommendable to harvest the aerial parts and the roots in the same year. If the aerial parts must be harvested, the roots should be harvested 1 week after because this will result in the most optimal concentration of bioactive compounds in both products.
Asunto(s)
Ácidos Cafeicos/análisis , Echinacea/química , Extractos Vegetales/análisis , Alcamidas Poliinsaturadas/análisis , Ácidos Cafeicos/aislamiento & purificación , Componentes Aéreos de las Plantas/química , Extractos Vegetales/aislamiento & purificación , Raíces de Plantas/química , Alcamidas Poliinsaturadas/aislamiento & purificación , Factores de TiempoRESUMEN
Roots of Echinacea purpurea and Echinacea pallida cultivated for 4 years in a North European climate were analyzed for seasonal variations in the concentrations of lipophilic constituents (alkamides, ketoalkenes, and ketoalkynes) and phenolic acids by harvesting five times during 1 year to establish the optimal time for harvest. A total of 16 alkamides, three ketoalkenes, two ketoalkynes, and four phenolic acids (echinacoside, cichoric acid, caftaric acid, and chlorogenic acid) were identified in aqueous ethanolic (70%) extracts by liquid chromatography-mass spectrometry and quantified by reverse-phase high-performance liquid chromatography. The major alkamides in the roots of E. purpurea were at their lowest concentration in the middle of autumn and early winter, and the total concentration of lipophilic compounds in E. pallida showed the same pattern. Moreover, all of the major phenolic acids in E. purpurea were at their highest concentrations in spring. The optimal harvest time in spring is in contrast to normal growing guidelines; hence, this specific information of seasonal variations in the concentrations of lipophilic and phenolic compounds in E. purpurea and E. pallida is valuable for research, farmers, and producers of medicinal preparations.