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Procyanidin B1 (procyanidin + b1)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Polyphenolic profile and antioxidant activity of five apple cultivars grown under organic and conventional agricultural practices

INTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 6 2009
Athanasios Valavanidis
Summary The polyphenols and total antioxidant activities of five apple cultivars, grown by organic and conventional agricultural methods in neighbouring farms, were determined and compared. Total polyphenols in the whole fruit and in the peel were determined by the Folin-Ciocalteu method, and the total antioxidant activity was determined by three established methods, diphenyl picrylhydrazyl (DPPH), azinobis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and ferric reducing/antioxidant power (FRAP). Polyphenolic content for the whole fruit was in the range of 80,196 and for the peel 165,400 (mg Gallic Acid Equivalent (GAE)/100 g fresh weight) for both types of agricultural practices. Antioxidant activities of fruit extracts were also relatively similar and well correlated to their polyphenolic content. High-performance liquid chromatography (HPLC) analysis of the most important polyphenolics (chlorogenic acid, catechin, epicatechin, procyanidin B1 and B2, cyaniding 3-galactoside, phloridzin, quercetin 3-galactoside and quercetin 3-arabinoside) also showed that concentrations do not differentiate significantly between the organic and conventional apples. Statistical significance of differences in antioxidant activities among the same cultivars was relatively small (flesh + peel or peel only) for both types of apples. These results indicate that organic apples do not present higher antioxidant or nutritional value compared with conventionally grown ones, as far as polyphenolic content and total antioxidant activities are concerned. [source]

Effect of ellagitannins, ellagic acid and volatile compounds from oak wood on the (+)-catechin, procyanidin B1 and malvidin-3-glucoside content of model wines

AUSTRALIAN JOURNAL OF GRAPE AND WINE RESEARCH, Issue 3 2008
A.M. JORDÃO
Abstract Background and Aims:, During ageing in oak barrels, wine undergoes changes because of the release of polyphenols and other molecules from wood. The aim of this study was to evaluate the influence of some oak wood-derived volatile compounds, ellagic acid and oak wood extracts on the levels of (+)-catechin, procyanidin B1 and malvidin-3-glucoside. Methods and Results:, Phenolics and the oak wood derived volatile compounds studied were quantified by HPLC and by GC, respectively. Additionally, the new compounds formed in the solutions were characterised by their spectral properties. Ellagic acid and/or oak wood extracts slowed the decline in the levels of (+)-catechin and procyanidin B1. In contrast, the decrease in malvidin-3-glucoside was more pronounced in the presence of ellagic acid and oak wood chip extracts. Furfural slowed (+)-catechin degradation, while breakdown of malvidin-3-glucoside was slightly more pronounced in the presence of guaiacol, furfural, vanillin and eugenol. (+)-Catechin, procyanidin B1 and malvidin-3-glucoside did not significantly affect the rate of the degradation of ellagitannins during the storage time studied. Finally, new HPLC peaks were detected in the solutions containing (+)-catechin and ellagic acid, as well as with malvidin-3-glucoside with ellagic acid and oak wood extract. Conclusions:, Malvidin 3-glucoside and (+)-catechin and procyanidin B1 presented distinct behaviours during time in the presence of volatile and non-volatile compounds from oak wood. Significance of the Study:, This work points out the importance of oak wood components in the degradation of anthocyanins and tannins, as well as the reactions that occur during the ageing of red wine. [source]

An analytical survey of the polyphenols of seeds of varieties of grape (Vitis vinifera) cultivated in Greece: implications for exploitation as a source of value-added phytochemicals

PHYTOCHEMICAL ANALYSIS, Issue 1 2005
Ramila Guendez
Abstract Seed samples from 12 white and 25 red international and Hellenic native grape varieties (Vitis vinifera) were screened for their polyphenolic composition. The polyphenols determined were mainly of low molecular weight, including gallic acid, catechin, epicatechin, epicatechin gallate, epigallocatechin, epigallocatechin gallate and the procyanidins B1 and B2. Average values of total content for white and red varieties (376 and 388 mg/100 g seeds, respectively) were very similar. Comparable results were observed with respect to the individual polyphenol content with seeds from red varieties being, in general, slightly richer. The predominant ,avanol monomer in white and red varieties was catechin (which accounted for 50.5 and 49.3%, respectively, of the total content), whilst gallic acid and epigallocatechin were the constituents showing the lowest content, respectively. The data obtained are discussed with regard to the exploitation of grape seeds as a low-cost source of value-added phytochemicals. Copyright © 2005 John Wiley & Sons, Ltd. [source]