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 ß-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.
La composicioÌn quiÌmica del aceite esencial y el contenido de carotenoides de la planta paraÌsita Cuscuta mitraeformis se describen por primera vez. El aceite esencial fue analizado por GC-FID y GC-MS siendo el nonanal (24.6%) el constituyente principal seguido del timol (16.5%) y el eugenol (7.5%). El contenido total de carotenoides (130 mg 100 g-1 PF) fue determinado por HPLC-DAD. La fraccioÌn de carotenoides contuvo ß-caroteno (76.4 mg 100 g-1 PF) y luteiÌna (18.9 mg 100 g-1 PF) como compuestos mayoritarios. Fue observada una actividad antioxidante deÌbil por parte del aceite esencial frente al radical DPPH (IC50, 1.4 mg mL-1), mientras que una fuerte actividad antioxidante fue determinada para la fraccioÌn de carotenoides (IC50, 60.1 µg mL-1). El aceite esencial inhibioÌ el crecimiento de Clavibacter michiganensis, Pseudomonas syringae pv. tomato y Erwinia carotovora con una concentracioÌn miÌnima inhibitoria de 122.5, 184.5, 234.2 µg mL-1, respectivamente.
Subject(s)
Oils, Volatile/pharmacology , Oils, Volatile/chemistry , Cuscuta/chemistry , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology , Carotenoids/analysis , Chromatography, Gas/methods , Chromatography, High Pressure LiquidABSTRACT
We report the results of in vitro anti-lipase and antioxidant assays using crude ethanolic extracts from 30 plants grown in Oaxaca, México. Anti-lipase tests were performed by using porcine pancreatic lipase (PPL) [EC 3.1.1.3] from Affymetrix/USB. The extracts of Solanum erianthum, Salvia microphylla, Brungmansia suaveolens and Cuphea aequipetala showed up to 60% PPL inhibition. The effect of these extracts on the kinetic parameters of PPL (Km= 0.36 mM, and Vmax=0.085 mM min -1) revealed that the alcoholic preparations of S. erianthum and C. aequipetala engendered a non-competitive inhibition (Vmax=0.055 mM min -1; Vmax= 0.053 mM min -1), whereas those of S. microphylla and B. suaveolens produced a mixed inhibition (Km= 0.567 mM, Vmax=0.051 mM min _1; Km=0.643 mM, Vmax= 0.042 mM min ¹). In addition to these findings, seven extracts from different plants were able to inhibit PPL in the range of 30-50%. Antioxidant tests against 2,2-Diphenyl-1-picryl hydrazyl (DPPH) confirmed that Arctostaphylos pungens, Gnaphalium roseum, Crotalaria pumila, Cuphea aequipetala, Rhus chondroloma, and Satureja laevigata possess relevant antioxidant activity (IC(5)0=50-80 μg mL¹). The general composition of the most effective ethanolic extracts was obtained in order to confirm their known chemistry reported by previous works. Comprehensive chemical analysis of the ethanolic extracts and their poisoning effects suggests that S. microphylla, C. aequipetala and A. pungens could be considered as the best sources with both desired properties.