Volatile compounds and bioactivity of Eremurus spectabilis (Ciris), a Turkish wild edible vegetable

Eremurus spectabilis grows in the spring as a wild vegetable and for many years has been used both as a food or food additive and for therapeutic purposes. This study investigated the total phenolic content and the antimicrobial, antioxidant, and antiradical activities of methanol, ethanol, and aqueous extracts of E. spectabilis (obtained from the Antalya region of Turkey). In addition, volatile compounds of E. spectabilis were characterized by using gas chromatography/mass spectrometry. Major components of E. spectabilis volatile compounds were carvone (44.64%), carvacrol (14.45%), pentane, 2-methyl- (7.34%), (E)-caryophyllene (5.57%), valencene (5.11%), cis-calamenene (2.01%), cadalene (1.10%), and acetic acid (1.12%). The highest total phenolic content was seen with methanol extract (mean±standard deviation, 31.92 ± 0.48 mg gallic acid equivalents/g dry extract). The ethanol extract showed the highest antiradical activity, with a 50% inhibitory concentration of 35.14 μg/L in the 1,1-diphenyl-2- picrylhydrazyl assay. The strongest antioxidant activity was detected in methanol extract (81.72 ± 0.62 mg ascorbic acid equivalents/g). Twelve bacteria species were used to analyze the antimicrobial activity of extracts. The 1% concentrations of all extracts showed no inhibitive effect on any bacterium. The most resistant bacterium was Yersinia enterocolitica, and the most sensitive bacterium was Pseudomonas aeruginosa. A positive correlation was seen between concentrations and inhibition zones, and some differences occurred between antimicrobial activity of other concentrations.