Essential oil composition, carotenoid profile, antioxidant and antimicrobial activities of the parasitic plant Cuscuta mitraeformis

Abstract

The chemical composition of the essential oil and carotenoid content of the parasitic plant Cuscuta mitraeformis are described for the first time. The essential oil was analyzed by GC-FID and GC-MS revealing nonanal (24.6%) as the main constituent followed by thymol (16.5%) and eugenol (7.5%). The total carotenoid content (130 mg 100 g-1 FW) was determined by HPLC-DAD. The carotenoid fraction contained β-carotene (76.4 mg 100 g-1 FW) and lutein (18.9 mg 100 g-1 FW) as the most abundant compounds. A weak antioxidant activity was observed by the essential oil against DPPH radical (IC50, 1.4 mg mL-1), whereas a strong antioxidant activity was determined for the carotenoid fraction (IC50, 60.1 μg mL-1). The essential oil inhibited the growth of Clavibacter michiganensis, Pseudomonas syringae pv. tomato and Erwinia carotovora with minimum inhibitory concentrations of 122.5, 184.5, 234.2 μg mL-1, respectively.