Volatile oil constituent and biological activity of Gundelia tournefortii L. from Iran

Gundelia tournefortii L. is an important food source and a well-known medicinal plant in Iran. In the present study, the Hydro-distilled volatile oils from the aerial parts of G. tournefortii was investigated by GC-MS and GC. A total of 41 compounds representing 96.2% of the volatile oil were identified. The main constituents were thymol (11.2%), γ-terpinene (9.8%), germacrene D (6.6%) and p-cymene (6.3%). The antimicrobial activities of different extracts of G. tournefortii were examined against five Gram-positive and four Gram-negative bacteria. The antioxidant activities of different extracts were evaluated with DPPH radical scavenging activity and their relationship with the phenolic composition were also determined spectrophotometerically. Methanol extract of G. tournefortii showed the strongest antioxidant activity (IC50= 40.3 µg/ml) and the highest total phenolic content (103.4 mgGA/g extract). Ethyl acetate extract demonstrated antibacterial effect against Bacillus cereus, Bacillus pumilus and Bacillus subtilis strains in concentration of 7.5 mg/ml. The data of this study suggests that the essential oil and extracts from G. tournefortii has great potential for application as a prospective source of antioxidant and antimicrobial agent in pharmaceutical and food industries.