Estudio fitoquimico y actividad antioxidante in vitro de hojas y flores de Passiflora mixta.

Abstract

The objective of this research is to study the photochemical composition and evaluate the in vitro antioxidant activity of leaves and flowers of wild curuba (Passiflora mixta). As a previous study a quality control of plant matter and a phytochemical screening for qualitative identification was performed. Secondary metabolites Flavonic type was identified by means of thin layer chromatography (TLC). Phenols and flavonoids were quantified throughout UV spectroscopy at three different extracts: ethyl acetate, methanol and ethanol 70 %. To quantify the phenols the Folin-Ciocalteu method was used, with Gallic acid as standard reference, whereas for analysis of flavonoids quercetin was used. Quantification of non-glycosylated flavonoids was performed using high performance liquid chromatography (HPLC) in hydrolyzed extracts and apigenin, quercetin and luteolin were used as reference standards. Analysis of scavenging activity of the free radical was performed in methanolic extract by in vivo tests with 2,2-diphenyl -1- picrylhydrazyl (DPPH). In the study we identified composite typical of Passiflora genus such as isovitexin, vitexin one-rhamnoside, isovitexin 2-O-rhamnoside and orientin. The maximum amount of total phenols is identified in hydroalcoholic extracts of leaves 3777,8 mg Eq Gallic acid /100 g plant material and flavonoids 2605,6 mg Eq quercetin /100 g plant matter in the same extract. HPLC analysis indicates that the major component was apigenin in flowers with 6,8 mg/100 g of vegetable matter and quercetin leaves with 1,3 mg / 100 g of vegetable matter. The ethanol extract of leaves present best antioxidant activity with an IC50 of 361,167 μg/mL compared with flowers having an IC50 of 479,44 μg/mL. In conclusion Passiflora mixta has better free radical scavenging activity in leaves compared with flowers. It is recommended that leaves for further phytochemical studies are used.