Total Procyanidins Research Articles

Processing and Storage Effects on Procyanidin Composition and Concentration of Processed Blueberry Products

Blueberries are a rich source of procyanidins that may contribute to the reduced risk of chronic disease; however, because of seasonal availability, the berries are commonly consumed in thermally processed forms after long-term storage. In this study, we evaluated the effects of processing and 6 months of storage on procyanidin composition and content of blueberries that were canned in syrup (CS), canned in water (CW), pureed, and juiced (nonclarified and clarified). Processing blueberries into various forms resulted in significant losses of total procyanidins, with only 19 and 23% being retained in nonclarified and clarified juices, 41% retained in purees, and 65 and 78% being retained in berries CS and CW. The mono- and dimers were retained to a much greater extent than larger oligomers in all products following processing. Procyanidins were further degraded during 6 months of storage, with only 8% and 11% retained in clarified and nonclarified juices, 7% retained in pureed, and 22 and 32% retained in berries CS and CW. Similar to results obtained following processing, mono- and dimers were better retained than larger oligomers. Methods are needed to prevent procyanidin losses during processing and storage.

Content and mean polymerization degree of procyanidins in extracts obtained from clear and cloudy apple juices

The polyphenol profile of apples and that of technologically differently treated apple juices has already been studied thoroughly; nevertheless, the content of polymeric procyanidins has not received much attention up to date. Therefore, procyanidins in extracts made from six blended apple juices and two authentic clear as well as cloudy apple juices (Malus domestica cv. Bohnapfel and Bittenfelder) were investigated. Our determinations revealed significant differences in the total procyanidin content between apple juice extracts obtained from clear and the corresponding cloudy juices under study. Depending on the apple cultivars used average amounts of total procyanidin content determined in the extracts made from clear and cloudy juices ranged from 28.4 +/- 4.4% to 49.0 +/- 5.7% and from 48.3 +/- 0.3% to 60.6 +/- 0.3%, respectively. As the mean degree of polymerization (DPm) is supposed to have an influence on bioavailability and toxicity on different cells lines used in in vitro systems, the average degree of polymerization of the juices under examination were determined. Depending on the cultivar used and the technology of juice processing the DPm ranged between 3.0 and 13.4.

Polyphenols Are Intensively Metabolized in the Human Gastrointestinal Tract after Apple Juice Consumption

Polyphenols are secondary plant compounds showing anticarcinogenic effects both in vitro and in animal experiments and may thus reduce the risk of colorectal cancer in man. The identification of polyphenol metabolites formed via their passage through the small intestine of healthy ileostomy subjects after apple juice consumption is presented. Identification and quantification of polyphenols and their metabolites were performed using HPLC-DAD as well as HPLC-ESI-MS/MS. Total procyanidin content (TPA) was measured, and additionally the mean degree of polymerization (DPm) of the procyanidins was determined in the apple juice and ileostomy effluents. As products of polyphenol metabolism, D-(-)-quinic acid and methyl esters of caffeic acid and p-coumaric acid are liberated from the corresponding hydroxycinnamic acid esters. 1-Caffeoylquinic acid and 3-caffeoylquinic acid were determined as products of isomerization. Phloretin 2'-O-glucoside (phloridzin) and phloretin 2'-O-xyloglucoside were metabolized into the corresponding aglycons phloretin and phloretin 2'-O-glucuronide and all were found in the ileostomy effluent. Ninety percent of the consumed procyanidins were recovered in the ileostomy effluent and therefore would reach the colon under physiologic circumstances. The DP m was reduced (DP m of apple juice=5.7) and varied depending on the time point of excretion. The gastrointestinal passage seems to play an important role in the colonic availability of apple polyphenols.

Flavonoid and Hydroxycinnamate Profiles of English Apple Ciders

Seventeen phenolic compounds in 23 English apple ciders were identified and quantified by HPLC-PDA-MS (2). The total phenolic content of the ciders varied greatly ranging from 44 to 1559 mg/L. Four groups of compounds were identified, flavan-3-ols, hydroxycinnamates, flavonols, and dihydrochalcones. Hydroxycinnamates were the predominant group of phenolics in the majority of the ciders. Procyanidins were analyzed by HPLC after thiolysis, and total procyanidin content ranged from 8 to 722 mg/L and an average degree of polymerization of 2.5-3.5. This investigation of a wide range of ciders has shown a substantial variation in the profile and quantity of the phenolics. The analysis of single variety ciders highlighted the importance of using an apple cultivar with a high phenolic content to produce a phenolic-rich cider. Adaptations to the cider-making process could be used to increase the phenolic content with potential health benefits.

HPLC Quantification of Vitexine-2″-O-rhamnoside and Hyperoside in Three Crataegus Species and Their Antimicrobial and Antiviral Activities

Crataegus sp., also known as “hawthorn”, is one of the most prescribed herbal drugs and approved to be used against congestive heart failure. The extract is required to be standardized according to its flavonoid (vitexine-2″-O-rhamnoside and hyperoside) and oligomeric procyanidin content by the European Pharmacopoeia (EP). In this study, the leaves and berries of three Crataegus species including C. aronia var. aronia, C. monogyna ssp. monogyna (from two different localities) as well as C. pseudoheterophylla growing in Turkey were evaluated for their vitexine-2″-O-rhamnoside and hyperoside content by reversed-phase HPLC as well as their total procyanidin amount by a spectrophotometric method. In addition, antibacterial, antifungal, and antiviral activities of the extracts were also determined. Our results indicated that C. monogyna ssp. monogyna samples of both localities met the criteria required by the EP for their total flavonoid amount (2.49 and 2.86%) and total proanthocyanidin content (1.56 and 2.22%). According to data we obtained, the extracts have been verified to be highly effective against Candida albicans and Herpes simplex virus.

Sorghum Bran in the Diet Dose Dependently Increased the Excretion of Catechins and Microbial-Derived Phenolic Acids in Female Rats

Sorghum bran is concentrated with procyanidins (predominately polymers), which may be beneficial for health in humans; however, the bioavailability of procyanidins is not well-understood. Female Sprague-Dawley rats were fed an AIN93G diet containing 0, 5, 10, 20, or 40% Hi-tannin sorghum bran (n = 5-7 for each group) for 50 days. Sorghum bran contained 23.3 mg/g of procyanidins. The urinary excretions of catechin, epicatechin, methylated catechins, and phenolic acids were analyzed using liquid chromatography-tandem mass spectrometry. Sorghum bran dose dependently increased the urinary excretion of catechin (0-2.2 nmol/day) and 3'-O-methylcatechin (0-9.5 nmol/day). Their serum concentrations also increased with dose (range of 0-14 nM for 3'-O-methylcatechin). Among the 14 phenolic acids analyzed, 3,4-dihydroxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, and 4-hydroxyphenylacetic acid dominated in the serum (1.8-8 micromol/L). In the urine, 3-methoxy-4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, and 3-hydroxyphenylpropionic acid dominated and their excretion increased significantly with the level of sorghum bran in the diet. The summed phenolic acid excretion was 0.8 micromol/day in the control group and increased to 23 micromol/day for 40% sorghum bran group. The hippuric acid excretion ranged from 2.2 to 16.2 micromol/day and peaked in the 10% sorghum bran group. On the basis of chromic oxide, a nonabsorbable marker, total procyanidins and polymers disappeared progressively, and significant degradation occurred in the cecum and colon. Catechins and procyanidins in sorghum were bioavailable; however, bacteria-derived phenolic acids were the predominant metabolites of procyanidins. Procyanidins degraded in the gastrointestinal tract. Depolymerization was not observed.

Cacao leaf procyanidins increase locally and systemically in response to infection by Moniliophthora perniciosa basidiospores

Flavan-3-ol monomers and oligomers from dimers to decamers were quantitatively determined by HPLC-FLD in leaves of four Theobroma cacao varieties. Cacao flush leaves had higher procyanidin content than mature leaves. Moniliophthora perniciosa basidiospore infection results in an increase in cacao leaf procyanidins in the inoculated leaves, as well as in the uninoculated, adjacent, older leaves on an actively growing branch, resulting in both a local and systemic increase in procyanidin content in response to infection. Procyanidin oligomers increased significantly in leaves of the less susceptible genotype Scavina 6 upon infection, and total procyanidin levels were higher than in Cacao Comum a more disease susceptible genotype. Selection of genotypes with high constitutive and/or inducible content of procyanidins in young flush leaves may be a strategy to develop witches’ broom disease resistant cultivars.

Procyanidin and Catechin Contents and Antioxidant Capacity of Cocoa and Chocolate Products

Cocoa and chocolate products from major brands were analyzed blind for total antioxidant capacity (AOC) (lipophilic and hydrophilic ORAC(FL)), catechins, and procyanidins (monomer through polymers). Accuracy of analyses was ascertained by comparing analyses on a NIST standard reference chocolate with NIST certified values. Procyanidin (PC) content was related to the nonfat cocoa solid (NFCS) content. The natural cocoa powders (average 87% of NFCS) contained the highest levels of AOC (826 +/- 103 micromol of TE/g) and PCs (40.8 +/- 8.3 mg/g). Alkalized cocoa (Dutched powders, average 80% NFCS) contained lower AOC (402 +/- 6 micromol of TE /g) and PCs (8.9 +/- 2.7 mg/g). Unsweetened chocolates or chocolate liquor (50% NFCS) contained 496 +/- 40 micromol of TE /g of AOC and 22.3 +/- 2.9 mg/g of PCs. Milk chocolates, which contain the least amount of NFCS (7.1%), had the lowest concentrations of AOC (80 +/- 10 micromol of TE /g) and PCs (2.7 +/- 0.5 mg/g). One serving of cocoa (5 g) or chocolate (15 or 40 g, depending upon the type of chocolate) provides 2000-9100 micromol of TE of AOC and 45-517 mg of PCs, amounts that exceed the amount in a serving of the majority of foods consumed in America. The monomers through trimers, which are thought to be directly bioavailable, contributed 30% of the total PCs in chocolates. Hydrophilic antioxidant capacity contributed >90% of AOC in all products. The correlation coefficient between AOC and PCs in chocolates was 0.92, suggesting that PCs are the dominant antioxidants in cocoa and chocolates. These results indicate that NFCS is correlated with AOC and PC in cocoa and chocolate products. Alkalizing dramatically decreased both the procyanidin content and antioxidant capacity, although not to the same extent.

Classification of apple fruits according to their maturity state by the pattern recognition analysis of their polyphenolic compositions

Polyphenolic profiles of cider apple cultivars were studied in order to differentiate fruits according to their maturity state (ripe or unripe). Thiolysis and direct solvent extracts of freeze-dried apple pulps and peels were analysed by HPLC-DAD. Univariate data treatment did not achieve the mentioned target; thus a multivariate approach was considered. For each apple tissue data set, several chemometric techniques were applied to the most discriminant variables. Cluster analysis allowed a preliminary study of the data structure. Then, supervised pattern recognition procedures, namely linear discriminant analysis, K-nearest neighbours, soft independent modelling of class analogy, and multilayer feed-forward artificial neural networks (MLF-ANN), were used to develop decision rules to classify samples in the established categories. Excellent results were afforded by MLF-ANN applied to the concentrations of total procyanidins and (+)-catechin and the average degree of polymerisation of procyanidins in apple pulp, with success in the prediction ability of 97% and 99% for unripe and ripe categories, respectively.

Technological Classification of Basque Cider Apple Cultivars According to Their Polyphenolic Profiles by Pattern Recognition Analysis

The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography--diode array detection analysis of crude extracts and after thiolysis. Data sets, consisting of individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins, were evaluated by multivariate chemometric techniques, to develop decision rules for classifying apple cultivars technologically into bitter and nonbitter categories. A preliminary study of the data structure was performed by cluster analysis and principal component analysis in each apple material. Bitter apple varieties presented higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Different classification systems for the two categories on the basis of the chemical data were obtained applying several supervised pattern recognition procedures, such as linear discriminant analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed forward artificial neural networks. Excellent performance in terms of recognition and prediction abilities for both categories (100% of hits) was achieved in every case (pulp, peel, or juice). Polyphenolic profiles of apple pulp, peel, or juice provide enough information to develop classification criteria for establishing the technological group of apple cultivars (bitter or nonbitter).

Polyphenolic profiles of Basque cider apple cultivars and their technological properties.

The polyphenolic compositions of 31 Basque cider apple cultivars were determined in pulp, peel, and juice by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis. Total polyphenols are distributed in a wide concentration range depending on the cultivar. Procyanidins are the class of polyphenols that present major concentrations in apple. Their average degrees of polymerization range from 4 to 8 depending on the cultivar. Apple cultivars were technologically classified into bitter and nonbitter categories using different classification systems obtained by applying several pattern recognition techniques, such as principal component analysis, K-nearest neighbors, soft independent modeling of class analogy, partial least-squares, and multilayer feed-forward-artificial neural networks, to apple pulp, peel, or juice data (individual polyphenol concentrations, total procyanidin content, and the average degree of polymerization of procyanidins). Bitter apple cultivars present higher contents of flavan-3-ols and/or dihydrochalcones than nonbitter cultivars. Detailed knowledge of the polyphenolic profile of each apple cultivar affords information about their susceptibility to oxidation, their sensory properties (bitterness, astringency), and their possible influence on the characteristics and quality of the final product (juice, cider) when apples are processed.

Predictive Analysis of Cocoa Procyanidins Using Near‐Infrared Spectroscopy Techniques

ABSTRACT A near‐infrared reflectance (NIR) spectroscopy technique for the prediction of procyanidins in cocoa beans (Theobroma cacao) has been developed. A select group of cocoa liquors from different origins used for the manufacture of chocolate were analyzed to determine quantitative levels of procyanidin oligomers (monomer to decamer) using normal‐phase high‐performance liquid chromatography. The calibration set included seasonal, environmental, and fermentation variations to cover the concentration range of procyanidins found at naturally occurring levels. The sample set was analyzed on FOSS NIR System II 6500 spectrophotometers and partial least‐squares algorithms developed. Very good calibration statistics were obtained for the prediction of the total procyanidin oligomers (r2 = 0.983) with standard deviation/standard error of cross validation ratio (SD/SECV) of 5.68. A global version of this calibration, involving 20 Foss instruments produced a calibration r2 = 0.98 with a SD/ SECV = 6.20. Procyanidins have attracted increasing attention because of the rapidly growing body of evidence associating these compounds with a wide range of potential health benefits. A rapid method for the analysis of procyanidins in cocoa liquors would be beneficial in quality‐control environments and would provide cost benefits to manufacturing operations.

Crataegus extract blocks potassium currents in guinea pig ventricular cardiac myocytes.

Crataegus extract is used in cardiology for the treatment of mild to moderate heart failure (NYHA II) in Germany. However, little is known about the electrophysiological actions of Crataegus extract in the heart. Recently, it was shown that Crataegus extract prolongs the refractory period in isolated perfused hearts and increases action potential duration in guinea pig papillary muscle. It was the aim of this study to find out the mechanism of the increase in action potential duration caused by Crataegus extract. Using the patch-clamp technique, we measured the effects of Crataegus extract (10 mg/l; flavonoid content: 2.25%, total procyanidin content: 11.3 +/- 0.4%) on the inward rectifier and the delayed rectifier potassium current in isolated guinea pig ventricular myocytes. To get some insight into the mechanism underlying the positive inotropic effect of Crataegus extract, we also looked for effects on the L-type calcium current. Crataegus extract slightly blocked both the delayed and the inward rectifier potassium current. The inhibition amounted to 25% and about 15%, respectively. This amount of inhibition of these repolarising currents is sufficient to explain the prolongation of action potential duration caused by Crataegus extract. To our surprise we could not detect any influence of Crataegus extract on the L-type calcium current. In summary, our results show that Crataegus extract blocks repolarising potassium currents in ventricular myocytes. This effect is similar to the action of class III antiarrhythmic drugs and might be the basis of the antiarrhythmic effects described for Crataegus extract. Our measurements of the L-type calcium current indicate that Crataegus extract's positive inotropic effect is not caused by phosphodiesterase inhibition or a beta-sympathomimetic effect.

Spectrophotometric determination of total procyanidins in wine vinegars

A widely-used method for the spectrophotometric determination of procyanidins in wines has been adapted to wine vinegar samples. Reagent concentrations have been established and the analytical method tested for possible matrix effects. The recovery of catechin was approximately 98% and the limit of reliable measurement was 0.48 mg l −1. The within-day and between-day precisions were evaluated and according to the two-tailed F-test the precisions were statistically equivalent. Application to wine vinegars obtained by traditional and quick acetification methods showed differences in concentration between the two groups.

Sensitivity of Crinipellis perniciosa to procyanidins from Theobroma cacao L.

Basidiospores from four geographic isolates of Crinipellis perniciosa (Stahel) Singer, the pathogen causing witches' broom disease in various members of the Sterculiaceae, Solanaceae and Bixaceae, were exposed to different concentrations of partially-purified oligomeric procyanidins (condensed tannins), (-)-epicatechin/(+)-catechin, and anthocyanins extracted from cocoa seeds. The effectiveness of the test compounds for inhibiting basidiospore germination and germ tube elongation was: a mixture of procyanidins with 5-8 monomeric units (n = 3-5) > a mixture of procyanidins with 3-5 monomeric units (n = 3-5) > a mixture of the B2 dimer of (-)-epicatechin and the B5 dimer of (-)-epicatechin and (+)-catechin > (-)-epicatechin/(+)-catechin ⩾ anthocyanins. Sensitivity to test compounds also varied among isolates, and could be used as a criterion to distinguish the isolates. A total procyanidin fraction had little or no effect on the growth rates of dikaryotic (saprophytic) mycelial cultures.

Procyanidine in Zapfen Von Pinus Halepensis

AbstractFrom The Unripe Cones Of Pinus Halepensis (Pinaceae), (+)- Catechin, (-)- Epicatechin and (+)-Gallocatechin As Peracetate Derivatives and Procyanidin Bl, B3, B4, B6 and B7 As Decaacetates Were Isolated and Identified. The Major Components Were (+)- Catechin, Procyanidin B3 and Procyanidin B6. The Unripe Cones Contained 4.63% Total Procyanidins.

The Procyanidins of White Grapes and Wines

Procyanidin extracts were prepared from a Seyval white wine, from a Müller-Thurgau wine fermented partly on its skins, and from grape seeds. The extracts were studied chromatographically, showing a range of discrete procyanidin oligomers up to the pentameric and significant quantities of more polymeric and oxidized material. Semi-quantitative estimations showed that the level of total procyanidins was as low as 5-10 mg/l in the Seyval wine rising to 300 mg/1 in the Müller-Thurgau, but that the qualitative distribution patterns of the catechins and procyanidins showed no marked differences between the two. The Müller-Thurgau extract was examined by counter-current distribution between ethyl acetate and water, thus achieving a separation of different groups of oligomeric procyanidins and this was followed by further chromatographic treatment on Sephadex LH-20. The four main procyanidin dimers of white wines were isolated in the free state and were characterized by chromatography and their degradative behavior in the presence of acidic toluene-thiol as procyanidins B1-B4. A further procyanidin fraction was isolated and shown to consist of a mixture of two stereoisomeric trimers, one composed of three epicatechin units and the other of two epicatechins and a terminal catechin. The English-grown MüllerThurgau wine was found to contain negligible amounts of gallocatechins and of galloyl esters of catechins, either alone or in combination as procyanidins; this is in contrast to some previous reports.