The effect of harvest time on the volatile compounds and bioactive properties of the flowers, leaves, and stems of Echinacea Pallida and its utilization to improve the oxidative stability of vegetable oils

Abstract

The present study was undertaken to investigate the effect of harvest time on the bioactive properties of Echinacea pallida and to determine the antioxidant effect of its extract in vegetable oils. E. pallida was harvested in June, 2009, June, 2010 and August. 2010. Total phenolic content and antioxidant activity analyses of the plant extracts obtained with three different solvents were carried out using spectrophotometric methods. It was determined that harvest time and solvent type had significant effects on bioactive properties. In addition, the effect of E. pallida extract on the oxidative stability of vegetable oils was determined by the rancimat method. The extract (2000 ppm) obtained by ethanol (100%) showed similar oxidative stability on sunflower and canola oils compared to BHA (100 ppm). The GC-MS results revealed various volatile compounds such as bornyl acetate, caryophyllene E, musk ambrette, germacrene D, alpha-muurolol, musk ambrette, imidazo (1,2-a) pyrimidine, 1-pyrrolidino-1-cyclohexene, 2,3,5,6-tetrahydro-1H-pyrrolizine, pyrazine, and benzenaminium.