Search results for "proanthocyanidins"

A hypotensive procyanidin-glycoside from Rhamnus lycioides ssp. lycioides.

1990

A lyophilized hot water extract of the aerial parts of Rhamnus lycioides L. (Rhamnaceae) produced a lowering of systemic arterial blood pressure in normotensive anaesthetized Wistar rats. An activity-guided fractionation of the methanolic extract led to the isolation of a tetrameric procyanidin-glycoside which produced a clear dose-dependent hypotensive response (1.5-6 mg/kg i.v.). This principle was characterized using acid hydrolysis, thiolytic degradation and spectroscopic methods. It consisted of four flavanol units with a 2,3-cis configuration and with a O-beta-d-glucosylpyranoside function on the epicatechin terminal unit. The interflavan linkage was (4-8).

Anti-inflammatory effects of sicilian pistachio (pistacia vera l.) Nut in an in vitro model of human intestinal epithelium

2015

Intestinal epithelial cells play an important role in the mucosal inflammatory response. These cells synthesize and secrete inflammatory mediators, and selectively modulate the permeability of the epithelial monolayer thus exposing immune cells to antigens. Although intestinal inflammatory response is crucial to maintain gut structural integrity and function, alteration and dysregulation of inflammatory pathways contribute to tissue damage and ulceration, and are thought to be pivotal factors in the pathogenesis of different inflammatory gut diseases [1]. The limited efficacy of conventional pharmacological therapy in the intestinal inflammatory conditions has fostered research on alternati…

Production of spray-dried proanthocyanidin-rich cinnamon (Cinnamomum zeylanicum) extract as a potential functional ingredient: Improvement of stabili…

2018

International audience; Cinnamon proanthocyanidins present important biological properties. However, these molecules are unstable and possess an astringent taste, which can make their ingestion difficult. In this context, entrapment by spray-drying technology may be used to produce a concentrated extract with improved stability and reduced astringency. Thus, this work aimed to prepare spray-dried microparticles loaded with a proanthocyanidin-rich cinnamon (Cinnamomum zeylanicum) extract (PRCE), immobilized in a maltodextrin matrix. Freeze-dried samples of the extract (without the carrier) were also prepared for comparison. The particles were characterized for moisture content, water activit…

Application of high Power ultrasounds during red wine vinification

2017

[EN] Wine colour is one of the main organoleptic characteristics influencing its quality. It is of special interest in red vinifications due to the economic resources that wineries have to invest for the extraction of the phenolic compounds responsible for wine colour, compounds that are mainly located inside the skin cell vacuoles, where the volatile compounds are also found. The transfer of phenolic compounds from grapes to must during vinification is closely related to the type of grapes and the winemaking technique. During traditional winemaking, grapes are crushed and skin macerated for several days, with pumps overs to facilitate the colour extraction. To increase this extraction, som…

Vaccinium macrocarpon (Cranberry)-Based Dietary Supplements: Variation in Mass Uniformity, Proanthocyanidin Dosage and Anthocyanin Profile Demonstrat…

2020

Vaccinium macrocarpon (syn. American Cranberry) is employed in dietary supplements (DS) with the aim to improve urinary tract well-being. This property is linked to the antiadhesion-activity of proanthocyanidins (PACs) against uropathogenic-bacteria. However, the current European legislation has been criticized for being weak and ineffective. Indeed, recent scientific works report mislabeled, contaminated, and adulterated supplements containing dangerous or unknown compounds, or sold at toxic doses. In this work, we analysed 24 DS that claim to contain cranberry, and to have a specific dosage of PACs. Our tests included the control of the good manufacturing practice according to the Europea…

Proanthocyanidins and Where to Find Them: A Meta-Analytic Approach to Investigate Their Chemistry, Biosynthesis, Distribution, and Effect on Human He…

2021

Proanthocyanidins (PACs) are a class of polyphenolic compounds that are attracting considerable interest in the nutraceutical field due to their potential health benefits. However, knowledge about the chemistry, biosynthesis, and distribution of PACs is limited. This review summarizes the main chemical characteristics and biosynthetic pathways and the main analytical methods aimed at their identification and quantification in raw plant matrices. Furthermore, meta-analytic approaches were used to identify the main plant sources in which PACs were contained and to investigate their potential effect on human health. In particular, a cluster analysis identified PACs in 35 different plant famili…

Anti-inflamamtory effects of Sicilian pistachio (Pistacia vera L.) nut in an in vitro model of human intestinal epithelium

2013

Over-evaluation of total flavonoids in grape skin extracts containing sulphur dioxide

2015

Abstract Sulphur dioxide (SO 2 ) proved to increase absorbance at 280 nm of grape skin and seed extracts containing it, diluted with ethanol–HCl to assess total flavonoids and anthocyanins in the same analysis. Additional absorbance at 280 nm was also observed in acetone:H 2 O extracts, if the acetone had not completely evaporated before the extracts were diluted with a solvent. Flavonoids were correctly quantified in the extracts when SO 2 or acetone were removed by solid-phase extraction with a C 18 RP as sorbent and methanol as eluting solvent.

Behaviour of some compounds with lmax at 280 nm in determination of total flavonoids of grape skin extracts made from a hydroalcoholic SO2-rich solve…

2010

This paper reports the results of a study on the ambiguous behaviour of substances with lmax at 280 nm in the determination of total flavonoids in whole grape skin extracts made from a hydroalcoholic SO2-rich solvent, apparently not eluted with methanol after absorption on a C18 cartridge employed for sample pre-concentration and SO2 removal. After rejecting the hypothesis that they were irreversibly absorbed on the C18 cartridge, it seemed that they reacted with other phenolics during passage through the C18 cartridge and were totally eluted with methanol in this new combined form. This new hypothesis seems very probable and is in accord with the more recent acquisition about the synthesis…

Chemical partitioning and DNA fingerprinting of some pistachio (Pistacia vera L.) varieties of different geographical origin

2019

The genus Pistacia (Anacardiaceae family) is represented by several species, of which only P. vera L. produces edible seeds (pistachio). Despite the different flavor and taste, a correct identification of pistachio varieties based on the sole phenotypic character is sometimes hard to achieve. Here we used a combination of chemical partitioning and molecular fingerprinting for the unequivocal identification of commercial pistachio seed varieties (Bronte, Kern, Kerman, Larnaka, Mateur and Mawardi) of different geographical origin. The total phenolic content was higher in the variety Bronte followed by Larnaka and Mawardi cultivars. The total anthocyanin content was higher in Bronte and Larnak…