Chemical composition and vasodilatation induced by Cuphea carthagenensis preparations

Abstract

The aerial parts of Cuphea carthagenensis (Jacq.) J.F. Macbride (Lythraceae) are traditionally employed in Brazil to treat cardiovascular diseases. The aim of this study was to compare preparations of C. carthagenensis aerial parts (aqueous and ethanol extracts, together with derived fractions) with regard to their total phenolic contents and in vitro vasodilating activity. The main flavonoids found in the extracts were isolated and identified as quercetin derivatives. The extracts and fractions showed similar HPLC profiles with the presence of quercetin-5-O-β-glucopyranoside, quercetin-3-O-α-arabinofuranoside and quercetin-3-sulfate in all of them, but marked differences in the contents of flavonoids, proanthocyanidins, tannis and total phenolics. Excepting the aqueous extract, all assayed preparations elicited vasodilatation on pre-contracted rat aortic rings in the range of pIC(50) 4.53±0.03 to 4.98±0.06. Polynomial regression analysis demonstrated the relationship between vasodilating activity and the contents of flavonoids (r(2)=0.5190), proanthocyanidins (r(2)=0.8016), tannins (r(2)=0.8041) and total phenolics (r(2)=0.6226), suggesting the participation of these compounds in the pharmacological effect and their potential use as chemical markers for the species.

Chemical profile of pineapple cv. Vitória in different maturation stages using electrospray ionization mass spectrometry

“…Analysis of phenolic compounds in the extracts was performed using a UV–visible spectrophotometer (model 482; Femto, São Paulo, Brazil) according to the spectrophotometric method of Folin–Ciocalteu with adaptations . Absorbance was registered at 715 nm.…”

Antioxidant, antimicrobial and wound healing properties ofStruthanthus vulgaris

“…The spectrophotometric Folin-Ciocalteu method was used to measure the total phenolic content (TPC) in the extracts, as previously described by Krepsky et al (2012) and Scherer and Godoy (2009). All the analyses were performed in triplicate and the results expressed as mean ± standard deviation.…”

“…The aluminum chloride colorimetric method was used for the determination of total flavonoid concentration, as previously described by Krepsky et al (2012). The content was calculated using the calibration curve of quercetin (1-12 mg/ml) and the results expressed in milligram of quercetin equivalents per gram of dry extract.…”

Phytochemical and in vitro and in vivo biological investigation on the antihypertensive activity of mango leaves (Mangifera indica L.)

“…Total phenolic contents were determined spectrophotometrically according to the Folin-Ciocalteu reagent method [Krepsky et al 2012]. Quantification was based on the standard curve generated with pyrogallol (3.125-37.5 µg/ml) and the results were expressed in milligrams of pyrogallol equivalents (PE) per 100 grams dry weight (mg PE/100 g).…”

“…Quantification was based on the standard curve generated with pyrogallol (3.125-37.5 µg/ml) and the results were expressed in milligrams of pyrogallol equivalents (PE) per 100 grams dry weight (mg PE/100 g). Determination of flavonoids was performed according to a colorimetric assay with aluminium chloride [Krepsky et al 2012]. The content of total flavonoids was calculated using a calibration curve of quercetin (1-12 µg/ml) and the results expressed in grams of quercetin equivalents per 100 g of dry weight.…”