Article

Phytochemical analysis of salal berry (Gaultheria shallon Pursh.), a traditionally-consumed fruit from western North America with exceptionally high proanthocyanidin content

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Abstract

Salal (Gaultheria shallon Pursh.) is a wild perennial shrub of the Ericaceae and common in coastal forests of western North America, and its berries were an important traditional food for First Nations in British Columbia. Salal berries were investigated for phytochemical content and antioxidant capacity over the course of fruit development. The proanthocyanidin content was extremely high in young berries (280.7 mg/g dry wt) but dropped during development to 52.8 mg/g dry wt. By contrast, anthocyanins accumulated only at the late berry stages. Total antioxidant capacity, as measured by the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) method, reflected both proanthocyanidin and anthocyanin content, and in mature berries reached 36 mmol Trolox equivalents/100 g dry wt. More detailed phytochemical analysis determined that delphinidin 3-O-galactoside is the dominant anthocyanin, and that the berries are also rich in procyanidins, including procyanidin A2 which has been implicated in anti-adhesion activity for uropathogenic E. coli. Proanthocyanidins were 60% prodelphinidin, and overall concentrations were higher than reported for many Vaccinium species including blueberry, lingonberry, and cranberry. Overall, the phenolic profile of salal berries indicates that these fruit contain a diversity of health-promoting phenolics.

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... Fruits from the Gaultheria genus (Ericaceae) are used worldwide as food and traditional medicines (Liu et al., 2013;Luo, Gu, Kennelly, & Long, 2018). Most studies have been carried out on Asian, North American and European species, including Gaultheria yunnanensis (Zhang, He, Ding, & Du, 2006) and G. shallon (Ferguson et al., 2018;McDougall, Austin, Van Schayk, & Martin, 2016). In Chile, five edible Gaultheria species can be found, namely: Gaultheria phillyreifolia, G. poeppigii, G. pumila, G. mucronata and G. tenuifolia (Teillier & Escobar, 2013). ...
... McDougall et al. (2016) described the main anthocyanins of G. shallon as delphinidin and cyanidin pentosides, hexosides and dipentosides. Ferguson et al. (2018) showed that the main anthocyanins in mature fruits of G. shallon were pentosides and hexosides of delphinidin, cyanidin, petunidin, malvidin and peonidin. In the Chilean G. antarctica and G. mucronata, the main anthocyanins identified were delphinidin and cyanidin pentosides, as well as cyanidin galactoside (Ruiz et al., 2013). ...
... The highest content of 6a was found in one of the G. phillyreifolia samples (131.2 mg/100 g fw). In G. shallon, the main anthocyanin was delphinidin-3-O-galactoside (2.6 g/100 g dry fruit) followed by delphinidin-3-O-arabinoside (0.7 g/100 g dry fruit) (Ferguson et al., 2018). In G. mucronata and G. antarctica, the main anthocyanin was cyanidin pentoside, with contents of 0.77 and 0.05 μmol/g fresh fruit, respectively (Ruiz et al., 2013). ...
... Fruits from the Gaultheria genus (Ericaceae) are used worldwide as food and traditional medicines (Liu et al., 2013;Luo, Gu, Kennelly, & Long, 2018). Most studies have been carried out on Asian, North American and European species, including Gaultheria yunnanensis (Zhang, He, Ding, & Du, 2006) and G. shallon (Ferguson et al., 2018;McDougall, Austin, Van Schayk, & Martin, 2016). In Chile, five edible Gaultheria species can be found, namely: Gaultheria phillyreifolia, G. poeppigii, G. pumila, G. mucronata and G. tenuifolia (Teillier & Escobar, 2013). ...
... McDougall et al. (2016) described the main anthocyanins of G. shallon as delphinidin and cyanidin pentosides, hexosides and dipentosides. Ferguson et al. (2018) showed that the main anthocyanins in mature fruits of G. shallon were pentosides and hexosides of delphinidin, cyanidin, petunidin, malvidin and peonidin. In the Chilean G. antarctica and G. mucronata, the main anthocyanins identified were delphinidin and cyanidin pentosides, as well as cyanidin galactoside (Ruiz et al., 2013). ...
... The highest content of 6a was found in one of the G. phillyreifolia samples (131.2 mg/100 g fw). In G. shallon, the main anthocyanin was delphinidin-3-O-galactoside (2.6 g/100 g dry fruit) followed by delphinidin-3-O-arabinoside (0.7 g/100 g dry fruit) (Ferguson et al., 2018). In G. mucronata and G. antarctica, the main anthocyanin was cyanidin pentoside, with contents of 0.77 and 0.05 μmol/g fresh fruit, respectively (Ruiz et al., 2013). ...
... Fruits from the Gaultheria genus (Ericaceae) are used worldwide as food and traditional medicines (Liu et al., 2013;Luo, Gu, Kennelly, & Long, 2018). Most studies have been carried out on Asian, North American and European species, including Gaultheria yunnanensis (Zhang, He, Ding, & Du, 2006) and G. shallon (Ferguson et al., 2018;McDougall, Austin, Van Schayk, & Martin, 2016). In Chile, five edible Gaultheria species can be found, namely: Gaultheria phillyreifolia, G. poeppigii, G. pumila, G. mucronata and G. tenuifolia (Teillier & Escobar, 2013). ...
... McDougall et al. (2016) described the main anthocyanins of G. shallon as delphinidin and cyanidin pentosides, hexosides and dipentosides. Ferguson et al. (2018) showed that the main anthocyanins in mature fruits of G. shallon were pentosides and hexosides of delphinidin, cyanidin, petunidin, malvidin and peonidin. In the Chilean G. antarctica and G. mucronata, the main anthocyanins identified were delphinidin and cyanidin pentosides, as well as cyanidin galactoside (Ruiz et al., 2013). ...
... The highest content of 6a was found in one of the G. phillyreifolia samples (131.2 mg/100 g fw). In G. shallon, the main anthocyanin was delphinidin-3-O-galactoside (2.6 g/100 g dry fruit) followed by delphinidin-3-O-arabinoside (0.7 g/100 g dry fruit) (Ferguson et al., 2018). In G. mucronata and G. antarctica, the main anthocyanin was cyanidin pentoside, with contents of 0.77 and 0.05 μmol/g fresh fruit, respectively (Ruiz et al., 2013). ...
Article
The berries from the native Chilean Gaultheria phillyreifolia and G. poeppigii are appreciated for their sweet taste and aroma. Fruits from both species were investigated for their secondary metabolite composition and antioxidant activity. The extracts were submitted to membrane chromatography to separate anthocyanins from copigments. Four anthocyanins were isolated by counter-current chromatography (CCC) and identified as cyanidin galactoside, cyanidin arabinoside, delphinidin galactoside and delphinidin arabinoside. From the copigments, CCC allowed the separation of quercetin(Q)-3-arabinoside, Q-3-rutinoside Q-3-rhamnoside and 3-caffeoylquinic acid. Additionally, the iridoids monotropein-10-trans-coumarate, monotropein-10-trans-cinnamate and 6α-hydroxy-dihydromonotropein-10-trans-cinnamate were isolated. The latter two iridoids are reported here for the first time. Some 34 other compounds were tentatively identified by HPLC-DAD-ESI-MSn. The antioxidant activity showed differences between anthocyanins and copigments from both species. Main compounds were quantified and submitted to a Partial-Least Square Discriminant Analysis (PLS-DA). This is the first report on the isolation of phytochemicals from the selected Chilean Gaultheria species.
... PAs can be analyzed at the compound level by liquid chromatography mass spectrometry (LC−MS) only for small oligomers, such as dimers to pentamers. 5,6 The larger oligomers and polymers can be detected by electrospray ionization mass spectrometry (ESI−MS) and matrix-assisted laser desorption/ionization− time-of-flight mass spectrometry (MALDI−TOF−MS) approaches up to relatively large polymers, but they cannot be separated as individual compounds by chromatographic techniques. ...
... This is nothing novel as such, and it should be expected from modern phytochemistry that all small-molecular-weight phenolics that elute as sharp peaks in the chromatographic step can be specifically detected by, e.g., MRM methods, because this has been possible with ellagitannin dimers to heptamers. 5,6,9 However, compoundspecific MRM methods need to be separately developed for every compound or at least isomer, by optimizing the ionspecific cone voltage and collision energy for the molecular ion and its fragment, respectively, and polymeric tannins cannot be to date analyzed individually by MRM methods, thus making these methods non-universal for general tannin detection. For this reason, the Engstrom method was developed as a single universal method that would be able to detect with the novel group-specific MRMs all tannins that contain the following functional units: (1) galloyl groups, (2) hexahydrodiphenoyl (HHDP) groups, (3) terminal and extension units of PCs, and (4) terminal and extension units of PDs ( Figure 1). ...
... We have now used this method in multiple studies to realize its full potential in characterizing the PA content of, e.g., ruminant feed varieties, 20 traditionally consumed fruit species, 6 and potential tannin-producing cell cultures 21 or to study the regulation of PA biosynthesis in poplars 22 and the distribution of PAs and HTs in 628 Eucalyptus species 23 or seeds of 196 tree and liana species growing in the tropics. 18 Although tannin chemists highly appreciate the traditional tannin characterization tools mentioned above (NMR, MALDI−TOF−MS, and thiolysis/phloroglucinolysis), the Engstrom method offers a new dimension to the tannin analysis in agricultural and food sciences or all sciences where tannins play their part. ...
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Tannins are large-molecular-weight plant polyphenols that are produced in fruits, berries, leaves, flowers, seeds, stems, and roots of woody and non-woody plants. Hundreds and thousands of individual tannin structures are consequently found in many kinds of natural food and feed products. The huge structural variability in tannins is reflected as vast bioactivity differences between them but not in the accuracy of their typical analysis methods. Here, I show how the modern liquid chromatography mass spectrometry methods can be used to obtain new types of two-dimensional tannin fingerprints to better visualize both the tannin content and diversity in plants with just one 10 min analysis per sample.
... Besides anthocyanins, chlorogenic, ellagic, and protocatechuic acids, as well as flavonols, flavan-3-ols, and proanthocyanidins (PAs) are also expected to contribute to these antidiabetic properties due to their ability to inhibit starch digestive enzymes (Kato et al., 2017;McDougall et al., 2005;Tadera et al., 2006). Light-colored berries have been associated with higher levels of chlorogenic acid derivatives such as 5-O-and 3-O-caffeoylquinic acids, flavonol glycosides, flavan-3-ols, and PAs, which are also partially responsible for phenolic health benefits (Ferguson et al., 2018). On this basis, berries with high phenolic contents are expected to be associated with superior health benefits. ...
... However, the crop wild relatives of some berries have even higher phenolic content than these commercial berries. For example, salal berries have a total phenolic content 6 times higher than black raspberry (Ferguson et al., 2018). Although 60% of the total phenolics in salal berries are composed of anthocyanins (mainly delphinidin-3-O-galactoside), salal berries have also high amounts of procyanidin A2, which has been implicated in anti-adhesion activity for uropathogenic E. coli (Nicolosi et al., 2014 Consequently, the high phenolic content of crop wild relatives is expected to confer outstanding nutraceutical properties. ...
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... Compound 24 presented a molecular mass of m/z 591 amu and secondary fragments ions at m/z 439, 301, and 289 amu, in agreement with (epi)-gallocatechin-(epi)-catechin (Esatbeyoglu et al., 2013). In the same line, Ferguson et al. (2018) reported prodelphinidin derivatives in the fruits from G. shallon. ...
... ide was 48.09 and 35.82 mg/100 g fw for the 2018 and 2019 collections, respectively (Table 2). The total content of anthocyanins was 41.28 and 51.21 mg/100 g fw for the 2018 and 2019 collections, respectively. The presence of pentosides and galactosides of cyanidin and delphinidin in G. antarctica and G. mucronata was reported byRuiz et al. (2013).Ferguson et al. (2018) reported the monoglycosides cyanidin, delphinidin, malvidin peonidin, and petunidin in Gaultheria shallon.Mieres-Castro et al. (2019) recently reported the presence of cyanidin and delphinidin galactosides and arabinosides in G. phillyreifolia and G. poeppigii. Similar content of anthocyanins was observed in G. poeppigii, ranging from 1 ...
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Gaultheria berries (Ericaceae) are consumed as food or used in folk medicine throughout the world. In the present study, Gaultheria tenuifolia berries were studied to describe their polyphenol and iridoid composition, aroma volatiles, and cytoprotective effects. In total, 14 metabolites were isolated using a combination of countercurrent chromatography and Sephadex LH‐20, namely, cyanidin‐3‐O‐β‐galactoside, cyanidin‐3‐O‐β‐arabinoside, 3‐O‐caffeoylquinic acid, 5‐O‐caffeoylshikimic acid, quercetin, quercetin‐3‐O‐β‐glucuronide, quercetin‐3‐O‐β‐rutinoside, quercetin‐3‐O‐β‐glucoside, quercetin‐3‐O‐β‐arabinoside, quercetin‐3‐O‐β‐rhamnoside, 6α‐hydroxydihydromonotropein‐10‐trans‐cinnamate, monotropein‐10‐trans‐cinnamate, and an (epi)‐catechin dimer and trimer. Other flavan‐3‐ols, proanthocyanidins, and iridoids were tentatively identified by spectroscopic and spectrometric means in the fruit extracts. The tentative volatile organic compound characterization pointed to methyl salicylate as responsible for the aroma of this species. The extracts showed significant cytoprotective effects in an oxidative stress model in human gastric epithelial cells. This is the first report on the isolation, characterization, and potential biological activity of secondary metabolites from G. tenuifolia berries and insights on its possible application as a functional food. Practical Application Berries are desirable fruit species because of their phytochemical composition and pleasant taste. Gaultheria berries are special due to their high content of iridoids and the presence of salicylic acid derivatives. Aroma of native berries is relevant for the development of new products reflecting the local identity and use of fruits. The present work involves cooperation of academia and industry on the constituents of the native products. The results provided in this article could be useful for the introduction of this species in the food and nutraceutical industries.
... Peak 20 was identified as a galloyl derivative (m/z = 461.07297) [9]. In the MS 2 spectrum, the precursor ion showed a fragment at m/z = 309.17999, ...
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... To verify the extraction efficiency, rosmarinic acid was used as internal standard and HPLC-DAD analyses were performed. As a result, the method performed byFerguson et al. (2018) was selected with slight modifications. Briefly, approx. ...
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Cool growing seasons, high rainfall, wind and reduced sunshine challenge fruit production in northern maritime regions. Salal (Gaultheria shallon Pursh) originates from the Pacific Northwest of North America and our research investigated its fruit production and chemical composition in Orkney, north of mainland Scotland. Materials and methods. Fruit production from a 20-plant row was recorded over 3 seasons and fruits were analysed for total polyphenol, anthocyanin content (TPC and TAC) and antioxidant capacity (FRAP). Results and discussion. Fruiting occurred from August to October. Although 16-18 pickings were required to harvest the entire crop, about 75% was picked over 4 weeks when maximum production occurred. Annual production varied from 0.7 to 2.3 kg m-1 of row, indicating potential yields of 2.7 to 9.1 t ha-1 at 10 years for hedgerows 2.5 m apart. In 2014, average fruit weight, height and diameter ranged from 467 to 680 mg, 9.9 to 10.5 mm and 9.2 to 10.2 mm, respectively. The maximum picking rate was about 1.0 kg h-1 but was constrained by poor synchronisation of fruit ripening. Variations between years in fruit TPC (658-968 mg 100 g-1 fw) were reflected in variations in TAC (121-219 mg 100 g-1 fw) and FRAP (63,048-100,815 μM Fe 100 g-1 fw). TPC and TAC values were similar to those for blackcurrant (Ribes nigrum L.) varieties. Conclusion. Salal grew well in Orkney's maritime environment and fruited reliably. This fruit has potential for novel food and drink, but commercialisation will require improved selections, notably for ease of harvest.
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Background Light is one of the most significant environmental factors affecting to the accumulation of flavonoids in fruits. The composition of the light spectrum has been shown to affect the production of phenolic compounds during fruit ripening. However, specific information on the biosynthesis of flavonoids in fruits in response to different wavelengths of light is still scarce. In the present study bilberry (Vaccinium myrtillus L.) fruits, which are known to be rich with anthocyanin compounds, were illuminated with blue, red, far-red or white light during the berry ripening process. Following the illumination, the composition of anthocyanins and other phenolic compounds was analysed at the mature ripening stage of fruits.ResultsAll the three monochromatic light treatments had significant positive effect on the accumulation of total anthocyanins in ripe fruits compared to treatment with white light or plants kept in darkness. The elevated levels of anthocyanins were mainly due to a significant increase in the accumulation of delphinidin glycosides. A total of 33 anthocyanin compounds were detected in ripe bilberry fruits, of which six are novel in bilberry (cyanidin acetyl-3-O-galactose, malvidin acetyl-3-O-galactose, malvidin coumaroyl-3-O-galactose, malvidin coumaroyl-3-O-glucose, delphinidin coumaroyl-3-O-galactose, delphinidin coumaroyl-3-O-glucose).Conclusions Our results indicate that the spectral composition of light during berry development has significant effect on the flavonoid composition of ripe bilberry fruits.
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Annual sprouting of aerial stems and ramets enables populations of salmonberry (Rubus spectabilis Pursh), salal (Gaultheria shallon Pursh), and probably other forest shrubs to maintain dense covers (>20 000 stems/ha). We studied annual stem production of salmonberry on cut (all stems cut within 15 cm of the ground) and uncut (stems were not treated) plots for 8 years and salal for 5 years in the understories of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco), alder, and riparian stands, as well as clearcuts, which are all common stand types in western Oregon. Mean salmonberry stem production on uncut plots ranged from 4.7 stems·m-2·year-1 (95% CI 2.9-7.4) in alder stands and clearcuts to 1.6 stems·m-2·year-1 (95% CI 1.0-2.6) in conifer stands. Mean salal production was greater, ranging from 58 stems·m-2·year-1 (95% CI 25-135) to 8.6 stems·m-2·year-1 (95% CI 3.7-20.1) on uncut plots in clearcuts and unthinned Douglas-fir stands, respectively. Annual production of both species was somewhat greater on cut plots. Most stems produced in early spring die by December, but enough are recruited to replace mortality of older stems. Stem density was maintained for 8 years for salmonberry and 5 years for salal on both cut and uncut plots. Based on length of rhizomes and bud density we estimate that only 1-5% of the buds in the rhizomes are needed to support this annual stem production. Although these species sprout vigorously after their aerial stems are killed, disturbance is not necessary for maintaining a dense cover. It appears that, once established, salal, salmonberry, and probably other clonal forest shrubs can maintain a dense cover that can interfere with establishment of trees and other shrubs in canopy gaps or other openings.
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Highbush blueberry (Vaccinium corymbosum) fruits contain substantial quantities of flavonoids, which are implicated in a wide range of health benefits. Although the flavonoid constituents of ripe blueberries are known, the molecular genetics underlying their biosynthesis, localization, and changes that occur during development have not been investigated. Two expressed sequence tag libraries from ripening blueberry fruit were constructed as a resource for gene identification and quantitative real-time reverse transcription-polymerase chain reaction primer design. Gene expression profiling by quantitative real-time reverse transcription-polymerase chain reaction showed that flavonoid biosynthetic transcript abundance followed a tightly regulated biphasic pattern, and transcript profiles were consistent with the abundance of the three major classes of flavonoids. Proanthocyanidins (PAs) and corresponding biosynthetic transcripts encoding anthocyanidin reductase and leucoanthocyanidin reductase were most concentrated in young fruit and localized predominantly to the inner fruit tissue containing the seeds and placentae. Mean PA polymer length was seven to 8.5 subunits, linked predominantly via B-type linkages, and was relatively constant throughout development. Flavonol accumulation and localization patterns were similar to those of the PAs, and the B-ring hydroxylation pattern of both was correlated with flavonoid-3'-hydroxylase transcript abundance. By contrast, anthocyanins accumulated late in maturation, which coincided with a peak in flavonoid-3-O-glycosyltransferase and flavonoid-3'5'-hydroxylase transcripts. Transcripts of VcMYBPA1, which likely encodes an R2R3-MYB transcriptional regulator of PA synthesis, were prominent in both phases of development. Furthermore, the initiation of ripening was accompanied by a substantial rise in abscisic acid, a growth regulator that may be an important component of the ripening process and contribute to the regulation of blueberry flavonoid biosynthesis.
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Moderate wine consumption is reputed to exert a protective effect against coronary heart disease (CHD). The nature of the protective compounds is unclear and the mechanisms are incompletely understood. We studied whether the nonalcoholic component of wine increases plasma antioxidant capacity measured as total radical-trapping antioxidant parameter (TRAP), and whether such an effect is associated with the presence of phenolic compounds in plasma. The TRAP and plasma levels of phenolic compounds were measured in 10 healthy subjects after the ingestion of 113 mL of tap water (control) and alcohol-free red and white wine at 1-wk intervals. Both alcohol-free wines possessed an in vitro dose-dependent peroxyl-radical activity, but red wine, with a polyphenol concentration of 363 +/- 48.0 mg/L quercetin equivalent (QE), was 20 times more active (40.0 +/- 0.1 mmol/L) than white wine (1.9 +/- 0.1 mmol/L), which has a polyphenol concentration of 31 +/- 1 mg QE/L. The ingestion of alcohol-free red wine caused significant increases in plasma TRAP values and polyphenol concentrations 50 min after ingestion. Alcohol-free white wine and water had no effects on either of the plasma values. The parallel and prompt increase of antioxidant status and of circulating levels of polyphenols in fasting subjects after bolus ingestion of a moderate amount of alcohol-free red wine suggests that polyphenols are absorbed in the upper gastrointestinal tract and might be directly involved in the in vivo antioxidant defenses.
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Methods available for the measurement of antioxidant capacity are reviewed, presenting the general chemistry underlying the assays, the types of molecules detected, and the most important advantages and shortcomings of each method. This overview provides a basis and rationale for developing standardized antioxidant capacity methods for the food, nutraceutical, and dietary supplement industries. From evaluation of data presented at the First International Congress on Antioxidant Methods in 2004 and in the literature, as well as consideration of potential end uses of antioxidants, it is proposed that procedures and applications for three assays be considered for standardization: the oxygen radical absorbance capacity (ORAC) assay, the Folin-Ciocalteu method, and possibly the Trolox equivalent antioxidant capacity (TEAC) assay. ORAC represent a hydrogen atom transfer (HAT) reaction mechanism, which is most relevant to human biology. The Folin-Ciocalteu method is an electron transfer (ET) based assay and gives reducing capacity, which has normally been expressed as phenolic contents. The TEAC assay represents a second ET-based method. Other assays may need to be considered in the future as more is learned about some of the other radical sources and their importance to human biology.
Article
Proanthocyanidins (syn condensed tannins) are complex flavonoid polymers naturally present in cereals, legume seeds and particularly abundant in some fruits and fruit juices. They share some common structural features—phenolic nature and high molecular weight—with phenolic polymers found in black tea and red wine (called here tannin‐like compounds). The polymeric nature of proanthocyanidins makes their analysis and estimation in food difficult. For this reason, little is known about their consumption, although they likely contribute a large part of the daily polyphenol intake. They also share common physicochemical properties: they form stable complexes with metal ions and with proteins and are, like other polyphenols, good reducing agents. Many of their biological effects of nutritional interest derive from these properties. As metal ion chelators, they influence the bioavailability of several minerals. The nutritional significance of the non‐specific complexation of proteins is less clear. As reducing agents, they may participate in the prevention of cancers, both of the digestive tract and inner organs. They may also protect LDLs against oxidation and inhibit platelet aggregation and therefore prevent cardiovascular diseases. In vitro , animal and human studies on the prevention of these chronic diseases are reviewed with particular attention to wine and tea polyphenols. The lack of data on their bioavailability and the paucity of human studies are emphasised. © 2000 Society of Chemical Industry
Chapter
Haslam’s previous accounts of this area of flavonoid chemistry (Haslam, 1975, 1982a) eloquently summarized the historical developments in the chemistry and biochemistry of this important and complex group of plant phenolics. Also covered were their relationship with condensed tannins and aspects of their characteristic chemical and spectroscopic properties and metabolism.
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A method for the screening of antioxidant activity is reported as a decolorization assay applicable to both lipophilic and hydrophilic antioxidants, including flavonoids, hydroxycinnamates, carotenoids, and plasma antioxidants. The pre-formed radical monocation of 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS*+) is generated by oxidation of ABTS with potassium persulfate and is reduced in the presence of such hydrogen-donating antioxidants. The influences of both the concentration of antioxidant and duration of reaction on the inhibition of the radical cation absorption are taken into account when determining the antioxidant activity. This assay clearly improves the original TEAC assay (the ferryl myoglobin/ABTS assay) for the determination of antioxidant activity in a number of ways. First, the chemistry involves the direct generation of the ABTS radical monocation with no involvement of an intermediary radical. Second, it is a decolorization assay; thus the radical cation is pre-formed prior to addition of antioxidant test systems, rather than the generation of the radical taking place continually in the presence of the antioxidant. Hence the results obtained with the improved system may not always be directly comparable with those obtained using the original TEAC assay. Third, it is applicable to both aqueous and lipophilic systems.
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The benefits of fruits and vegetables in human health have long been recognized. Part of the beneficial effects of these foods on human health has been purported to be due to various polyphenolic compounds that have radical scavenging and antioxidant activity. Saskatoon fruits (Amelanchier alnifolia Nutt.) are native to Western Canada and are an emerging North American fruit crop. The blue-purple coloration of mature saskatoon fruit, an important quality characteristic, is due to the presence of anthocyanins, which are a class of polyphenolic compounds that contribute to protection against human diseases. The objective of this review is to summarize the research on anthocyanins, a potential nutraceutical, and other nutrient components in saskatoon fruits. In addition, management practices to increase anthocyanin content in the mature fruit are discussed.
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We characterized the structure of condensed tannins from 16 woody plant species (seven genera, six families) and determined their effects on six herbivorous insect species (four genera, two families). There were major differences in tannin structure, even between congeneric plant species. Condensed tannins differed markedly in their antiherbivore activity, averaged over these herbivores, and the herbivores differed in their sensitivity, averaged over these tannins. Furthermore, the same tannin can have different effects on different herbivores, presumably because of interactions between tannin structure and gut physiology. Results challenge the view that tannins provide an evolutionarily stable plant defense because of their uniform chemical properties. Condensed tannin can sometimes impact herbivore fitness through effects on survival and growth, but the largest effects in 45 insect-tannin combinations were less than that of many other plant metabolites at lower doses. Even at high doses, condensed tannins frequently had no strong antiherbivore activity, even against insects with no evolutionary history of encountering the tannin (< 10% reduction in growth rate in 24 of 45 experiments). Most condensed tannins apparently do not have broad-spectrum antiherbivore activity. We doubt that selective pressures from folivorous insects can be the main explanation for the diversion of so much carbon, in so many plant species, into the synthesis of condensed tannins.
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Saskatoons (Amelanchier alnifolia Nutt.) are small fruits that contain substantial quantities of flavonoids. To further characterize and understand the role of these flavonoids during fruit development, anthocyanins, flavonols, and proanthocyanidins were identified, quantified, and localized over development in cultivars that produce blue-purple or white fruit at maturity. Anthocyanin content was low in young fruit, then dramatically increased as the fruit transitioned into ripening only in the pigmented-fruit (blue-purple) cultivars. Proanthocyanidins with both A-type and B-type linkages were detected in fruit, with (-)-epicatechin as the most abundant proanthocyanidin subunit. Flavonol and proanthocyanidin content was high in, and localized throughout, the tissues of young fruit, and in the developing seed coats, with levels decreasing as the fruit expanded. Our data shows that flavonoid type, content, and tissue localization varies throughout development in saskatoon fruit. These data can be used to target specific fruit developmental stages and flavonoid classes for optimization of health-beneficial flavonoid content.
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We developed a rapid method with ultra-performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS) for the qualitative and quantitative analysis of plant proanthocyanidins (PAs) directly from crude plant extracts. The method utilizes a range of cone voltages to achieve the depolymerization step of both smaller oligomers and larger polymers in the ion source. The formed depolymerization products are further fragmented in the collision cell to enable their selective detection. This UPLC-MS/MS method is able to separately quantify the terminal and extension units of the most common PA sub-classes, i.e. procyanidins (PC) and prodelphinidins (PD). The resulting data enable (1) quantification of the total PA content, (2) quantification of total PCs and PDs including the PC/PD ratio, (3) estimation of the mean degree of polymerization for the oligomers and polymers, (4) estimation of how the different PC and PD types are distributed along the chromatographic hump typically produced by large PAs. All this is achieved within the 10 minute period of analysis, which makes the presented method a significant addition to the chemistry tools currently available for the qualitative and quantitative analysis of complex proanthocyanidin mixtures from plant extracts.
Article
Wild lowbush blueberries (Vaccinium angustifolium Ait) are a rich source of anthocyanins and other flavonoids with anti-inflammatory activities, however their individual effects on cellular signaling remain to be elucidated. In this study we determined the capacity of blueberry bioactives to protect murine RAW 264.7 macrophages from lipopolysaccharide-induced inflammation. Fractionation of the crude extract (CE) into polyphenol-rich (PPR), anthocyanin-rich (ANC), proanthocyanidin-rich (PAC), and an ethyl acetate fraction (EA) revealed that PPR, ANC, and PAC components most effectively suppressed mRNA biomarkers of acute inflammation (Cox-2, iNOS, and IL-1). Among major polyphenols found in the wild blueberries, malvidin-3-glucoside was significantly more effective than epicatechin or chlorogenic acid in reducing the expression of pro-inflammatory genes in vitro.
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Wild Alaskan Vaccinium berries, V. vitis-idaea (lowbush cranberry) and V. uliginosum (bog blueberry), were investigated in parallel to their commercial berry counterparts; V. macrocarpon (cranberry) and V. angustifolium (lowbush blueberry). Lowbush cranberry accumulated about twice the total phenolics (624.4 mg/100 g FW) and proanthocyanidins (278.8 mg/100 g) content as commercial cranberries, but A-type proanthocyanidins were more prevalent in the latter. Bog blueberry anthocyanin and total phenolic contents of 220 and 504.5 mg/100 g, respectively, significantly exceeded those of the lowbush blueberry. Chlorogenic acid, however, was quite high in lowbush blueberry (83.1 mg/100 g), but undetected in bog blueberry, and the proanthocyanidins of lowbush blueberry had significantly higher levels of polymerization. Antioxidant capacity (DPPH, APTS and FRAP) correlated with phenolic content for each berry. A polyphenol-rich fraction from lowbush cranberry exhibited dose-dependent inhibition of LPS-elicited induction of IL-1β in RAW 264.7 cells, indicative of strong anti-inflammatory activity. These results corroborate the historic use of wild Alaskan berries as medicinally-important foods in Alaska Native communities.
Article
Twenty-two species of Gaultheria were examined for phenols and phenolic acids obtained by hydrolysis of ethanolic extracts. Most species yielded p-hydroxybenzoic, o-pyrocatechuic, protocatechuic, gentisic, vanillic, p-coumaric, caffeic and ferulic acids. Thirteen species contained derivatives of salicylic acid as well; the glycoside gaultherin was isolated from two of these. The three species of the section Amblyandra yielded catechol as the major phenol in hydrolyzates of ethanolic extracts. Catechol-β-D-glucopyranoside was isolated from one of these. The relationship of these phenolic compounds to one another is discussed.
Article
Effects of enzymatic and non-enzymatic juice pressing on key orosensory and chemical quality factors of blackcurrant juices were studied in laboratory scale using berries of five different cultivars (Mortti, Mikael, Marski, Ola and Breed15). Enzymatic processing increased the juice yield by 10-22% and the content of various phenolic compounds in juice by 4-10-fold as compared to the non-enzymatic process. Higher intensity of the mouth-drying astringency of the enzyme-aided juice was the most significant orosensory difference between the processes. Juices of different blackcurrant cultivars varied in sweetness, sourness and bitterness. The most intensive sensory attributes of the juices were sourness and puckering astringency regardless of processing method. They correlated positively with each other and were contributed by acid content and pH. In enzyme-aided juices, the contents of flavonol glycosides and hydroxycinnamic acids were associated with mouth-drying astringency, and sugar/acid ratio correlated with sweetness. These correlations were less clear in non-enzyme juices possibly due to lower content of phenolic compounds and the high content of pectin.
Article
Although the fruits are the economic driver for the black currant industry, the buds and leaves are excellent sources of beneficial phenolic compounds that may contribute to the future value of the crop. In this study, extraction of phenolic compounds for different parts of the black currant plant was optimized, and an efficient method for their separation by HPLC was developed. This allowed the simultaneous quantification of a range of hydroxycinnamic acids, flavan-3-ols, flavonols, and anthocyanins by DAD following their identification by HPLC-ESI-MS(n). A total of 23 compounds were detected in the buds, 22 of which were found in fruit and leaves. To the best of our knowledge, this is the first report of flavonol glycosides of quercetin, myricetin, isorhamnetin, and kaempferol along with hydroxycinnamic acids such as neo-chlorogenic acid and chlorogenic acid in the buds. Additionally, we provide the first evidence of kaempferol-3-O-rutinoside in black currant leaves. This approach offers avenues for superior combined compositional identification and cultivar selection targeted at the generation of polyphenol-rich products derived from the whole crop and not just the fruit.
Article
The metabolic pigment composition of Sangiovese wines produced from grapes harvested at 20 different vineyards in Montalcino over three consecutive years (2008-2010) on a semi-industrial scale and of 55 commercial Brunello di Montalcino wines (2004-2007) was studied, using a targeted method capable of analyzing 90 pigments in an 11 min UHPLC-MS/MS chromatographic run. Interesting correlations were shown between various pigments formed during wine aging and those present in Sangiovese grapes. Vitisin B-like pigment and vitisin A-like pigment concentrations would seem to have a good correlation with ethyl-linked and direct-linked flavanol-anthocyanin concentrations, respectively. Moreover, the anthocyanic pattern recognition, genetically controlled by the plant variety, was shown to be inherited by the pigments formed during wine aging.
Article
Representative condensed and hydrolyzable tannins and related simple phenolics were evaluated as biological antioxidants using cyclic voltammetry, the metmyoglobin assay, and the deoxyribose assay. The redox potentials of the tannins were similar to those of structurally related simple phenolics. However, the tannins were 15−30 times more effective at quenching peroxyl radicals than simple phenolics or Trolox. One of the tannins, polygalloyl glucose, reacted an order of magnitude more quickly with hydroxyl radical than mannitol. These results suggest that tannins, which are found in many plant-based foods and beverages, are potentially very important biological antioxidants. Keywords: Tannins; plant phenolics; antioxidant; total antioxidant activity; oxidative damage; dietary antioxidant
Article
The antihypertensive effect of a single oral administration of a boysenberry seed polyphenol extract to spontaneously hypertensive rats was evaluated at different doses (100 and 200 mg/kg), and a significant decrease in systolic blood pressure (SBP) was observed up to 6 h post administration. The extract was separated into proanthocyanidin-rich and ellagitannin fractions by solvent partition. A significant decrease in SBP was observed only after administering the proanthocyanidin-rich fraction, and this decrease was abolished by an N(G)-nitro-L-arginine methyl ester (L-NAME) injection. An analysis of the orally absorbable components showed that intact dimeric and trimeric procyanidins and propelargonidins were detectable in the plasma with a maximal concentration 2 h post administration. The vasorelaxant activity of the extract was also confirmed by in vitro assay using rat aorta rings. These results suggest that proanthocyanidins (PAs) in boysenberry seeds may have played an important role in the observed antihypertensive effect.
Article
Cranberry procyanidins have been associated with an effect against urinary tract infections (UTI) for decades, and European health claims are requested. This study compares the procyanidin profiles and concentrations of American cranberry ( Vaccinium macrocarpon Ait.), European cranberry ( Vaccinium oxycoccus L.), and lingonberry ( Vaccinium vitis-idaea L.) analyzed using ultrahigh-performance liquid chromatoraphy coupled to a triple-quadrupole mass spectrometer with electrospray interface (UHPLC-MS(2)). Concentrations of A-type trimers, procyanidin A2, catechin, epicatechin, and B-type dimers and trimers have been evaluated and compared for the first time in the three berries. The data clearly show remarkable differences in the procyanidin profiles and concentrations, especially the lack of A-type trimers in V. oxycoccus; thus, the effectiveness against UTI may vary among the Vaccinium species. These differences can be used to prove authenticity.
Article
The flavan-3-ol and proanthocyanidin composition of both seeds and skin of Vitis vinifera L. cv. Shiraz grapes was determined by reversed-phase HPLC after acetone extraction and acid-catalysis in the presence of excess phloroglucinol. Samples were taken at weekly intervals from fruit-set until commercial harvest. The main period of proanthocyanidin accumulation in grape seeds occurred immediately after fruit-set with maximum levels observed around veraison. Over two seasons there was variation in both the timing and content of proanthocyanidins in seeds. In skin, proanthocyanidin accumulation occurred from fruit set until 1–2 weeks after veraison. Proanthocyanidin subunit composition was different in seeds and skin and changed during berry development but the mean degree of polymerisation of the tannin polymers in skins was higher than in the seeds at all stages of berry development. Proanthocyanidin levels in both seeds and skin decreased between veraison and harvest. Additional proanthocyanidin subunits were released when the residues remaining after acetone extraction were subjected to direct acid-catalysis in the presence of phloroglucinol. In the seeds, these accounted for much of the post-veraison decrease, but not in grape skin. At harvest, 75% of extractable berry proanthocyanidin was in the seeds. Accumulation of proanthocyanidins in the seeds appears to be independent of that in the skins, but in both tissues synthesis occurs early in berry development and maximum levels are reached around veraison.
Article
Proanthocyanidins (syn condensed tannins) are complex flavonoid polymers naturally present in cereals, legume seeds and particularly abundant in some fruits and fruit juices. They share some common structural features—phenolic nature and high molecular weight—with phenolic polymers found in black tea and red wine (called here tannin-like compounds). The polymeric nature of proanthocyanidins makes their analysis and estimation in food difficult. For this reason, little is known about their consumption, although they likely contribute a large part of the daily polyphenol intake. They also share common physicochemical properties: they form stable complexes with metal ions and with proteins and are, like other polyphenols, good reducing agents. Many of their biological effects of nutritional interest derive from these properties. As metal ion chelators, they influence the bioavailability of several minerals. The nutritional significance of the non-specific complexation of proteins is less clear. As reducing agents, they may participate in the prevention of cancers, both of the digestive tract and inner organs. They may also protect LDLs against oxidation and inhibit platelet aggregation and therefore prevent cardiovascular diseases. In vitro, animal and human studies on the prevention of these chronic diseases are reviewed with particular attention to wine and tea polyphenols. The lack of data on their bioavailability and the paucity of human studies are emphasised.© 2000 Society of Chemical Industry
Article
It is known that the Coast Salish Indians of Vancouver Island used 122 species of plants. Means of collection, preparation, and utilization of these plants are outlined. The role of plants in Salish culture and economy for food, technology, medicine, religion, recreation, linguistics, and migration and settlement patterns is discussed. When possible, phonetic transcriptions are given of Salish names of plants. The ethnobotanies of the Island and related Salish and other Northwest Coast Indian groups are briefly compared. Sixty percent of the plants used by the Western Washington Salish and 20% of the species used by the Thompson Interior Salish were used similarly by the Island Salish. It is concluded that these differences are mainly the result of differences in regional vegetation, extent of trade and inter-group communications, similarity of cultural traits, and the degree of secrecy surrounding use. A map shows the territory of the Vancouver Island Salish and linguistic subdivisions. Summaries of plant uses are given in an Appendix.
Article
142 plant species are known to be recognized by the Southern Kwakiutl Indians of British Columbia. Means of collection, preparation, and utilization of these plants are outlined. The role of plants in Kwakiutl culture and economy for food, technology, medicine, religion, recreation, linguistics, and migration and settlement patterns is discussed. Phonetic transcriptions are given of most Kwakiutl names of plants. The ethnobotanies of the Southern Kwakiutl and the Vancouver Island Coast Salish are briefly compared. 50% of the plants were used similarly by both groups. Most differences seem related to vegetation characteristics, degree of trade and communication, cultural features, and religious secrecy. The extent and even the type of use of species occurring in both areas often appeared to be related more to species abundance than to any inherent plant characteristics.
Article
Compelling evidence of the health benefits of phenolic compounds and their impact on food quality have stimulated the development of analytical methods for the identification and quantification of these compounds in different matrices in recent years. A targeted metabolomics method has been developed for the quantification of 135 phenolics, such as benzoates, phenylpropanoids, coumarins, stilbenes, dihydrochalcones, and flavonoids, in fruit and tea extracts and wine using UPLC/QqQ-MS/MS. Chromatography was optimized to achieve separation of the compounds over a period of 15 min, and MRM transitions were selected for accurate quantification. The method was validated by studying the detection and quantification limits, the linearity ranges, and the intraday and interday repeatability of the analysis. The validated method was applied to the analysis of apples, berries, green tea, and red wine, providing a valuable tool for food quality evaluation and breeding studies.
Article
The hydrolysis of proanthocyanidins to anthocyanidins in n-BuOH-HCl (95:5) has been shown to be an autoxidation, the yield of anthocyanidin being critically dependent on trace metal-ion impurities. Reproducible yields of anthocyanidin may be achieved if iron (III) salts are added to the reaction medium, and a standard method of analysis of proanthocyanidins based on use of an n-BuOH-HCl-FeIII mixture is given. The ratio of absorbance maxima of the cyanidin (550 nm) produced to that near 280 nm for the original procyanidin polymer solution was ∼ 3.5.
Article
Condensed tannins (CTs) are a major component of litter inputs, but little is known about the effects of tannin structural variations on soil biological processes and organic matter development. Four different CTs extracted from balsam fir, western red cedar, kalmia and black spruce were added to Corsican pine litter and subsequently incubated for 16 weeks in order to investigate the effect of the B ring hydroxylation pattern on C, N and P transformations. While for C mineralization the chain length and stereochemistry of the CTs seemed to be a more important parameter, net N and P mineralization rates were clearly reduced compared with non-amended litter. With regard to the B ring hydroxylation, the prodelphinidin (PD) CTs having predominantly three hydroxy groups at the B ring (balsam fir and western red cedar) exhibited significantly lower mineralization rates than the procyanidin (PC) CTs having two OH groups (kalmia and black spruce). The same was true for net nitrification, but this process was only slightly affected by the CTs. Although based on only four CTs, this study indicates that B ring hydroxylation is an important variable determining net N and P mineralization rates. Our results support previous suggestions that PD tannins bind to or react more strongly with soil organic matter. Therefore, more than PC tannins, they reduce the availability of organic N for mineralization as well as their own detectability by standard methods for soil CT.
Article
Tannin toxicity for fungi, bacteria and yeasts is reviewed and compared to toxicity of related lower molecular weight phenols. The dependence of toxicity on tannin structure is examined. The different mechanisms proposed so far to explain tannin antimicrobial activity include inhibition of extracellular microbial enzymes, deprivation of the substrates required for microbial growth or direct action on microbial metabolism through inhibition of oxidative phosphorylation. A further mechanism involving iron deprivation is proposed. Many microorganisms can overcome plant defences based on tannins. They may detoxify tannins through synthesis of tannin- complexing polymers, oxidation, tannin biodegradation or synthesis of siderophores.
Article
Ethyl acetate extracts of Sephadex LH20-purified proanthocyanidins of American cranberry (Vaccinium macrocarpon Ait.) exhibited potent biological activity by inhibiting adherence of uropathogenic isolates of P-fimbriated Escherichia coli bacteria to cellular surfaces containing α-Gal(1 → 4)β-Gal receptor sequences similar to those on epithelial cells in the urinary tract. The chemical structures of the proanthocyanidins were determined by NMR, electrospray mass spectrometry, matrix-assisted laser absorption time-of-flight mass spectrometry and by acid catalyzed degradation with phloroglucinol. The proanthocyanidin molecules consisted predominantly of epicatechin units with mainly DP of 4 and 5 containing at least one A-type linkage. The procyanidin A2 was the most common terminating unit occurring about four times as frequently as the epicatechin monomer.
Article
Wild blueberries are a rich source of polyphenols and other compounds that are highly metabolized by the intestinal microbiota and may, at the same time, affect the intestinal environment itself. A repeated-measure, crossover dietary intervention on human volunteers was designed to study the effect of six week consumption of a wild blueberry ( Vaccinium angustifolium ) drink, versus a placebo drink, in modulating the intestinal microbiota. Relative to total eubacteria, Bifidobacterium spp. significantly increased following blueberry treatment (P ≤ 0.05), while Lactobacillus acidophilus increased after both treatments (P ≤ 0.05). No significant differences were observed for Bacteroides spp., Prevotella spp., Enterococcus spp., and Clostridium coccoides . Bifidobacteria, which have been largely proposed to be of benefit for the host, appeared to be selectively favored suggesting an important role for the polyphenols and fiber present in wild blueberries. Results obtained suggest that regular consumption of a wild blueberry drink can positively modulate the composition of the intestinal microbiota.
Article
Tannins are the most abundant secondary metabolites made by plants, commonly ranging from 5% to 10% dry weight of tree leaves. Tannins can defend leaves against insect herbivores by deterrence and/or toxicity. Contrary to early theories, tannins have no effect on protein digestion in insect herbivores. By contrast, in vertebrate herbivores tannins can decrease protein digestion. Tannins are especially prone to oxidize in insects with high pH guts, forming semiquinone radicals and quinones, as well as other reactive oxygen species. Tannin toxicity in insects is thought to result from the production of high levels of reactive oxygen species. Tannin structure has an important effect on biochemical activity. Ellagitannins oxidize much more readily than do gallotannins, which are more oxidatively active than most condensed tannins. The ability of insects to tolerate ingested tannins comes from a variety of biochemical and physical defenses in their guts, including surfactants, high pH, antioxidants, and a protective peritrophic envelope that lines the midgut. Most work on the ecological roles of tannins has been correlative, e.g., searching for negative associations between tannins and insect performance. A greater emphasis on manipulative experiments that control tannin levels is required to make further progress on the defensive functions of tannins. Recent advances in the use of molecular methods has permitted the production of tannin-overproducing transgenic plants and a better understanding of tannin biosynthetic pathways. Many research areas remain in need of further work, including the effects of different tannin types on different types of insects (e.g., caterpillars, grasshoppers, sap-sucking insects).
Article
Different cultivars of four Vaccinium species [Vaccinium corymbosum L (Highbush), Vaccinium ashei Reade (Rabbiteye), Vaccinium angustifolium (Lowbush), and Vaccinium myrtillus L (Bilberry)] were analyzed for total phenolics, total anthocyanins, and antioxidant capacity (oxygen radical absorbance capacity, ORAC). The total antioxidant capacity of different berries studied ranged from a low of 13.9 to 45.9 micromole Trolox equivalents (TE)/g of fresh berry (63.2-282.3 micromole TE/g of dry matter) in different species and cultivars of Vaccinium. Brightwell and Tifblue cultivars of rabbiteye blueberries were harvested at 2 times, 49 days apart. Increased maturity at harvest increased the ORAC, the anthocyanin, and the total phenolic content. The growing location (Oregon vs Michigan vs New Jersey) did not affect ORAC, anthocyanin or total phenolic content of the cv. Jersey of highbush blueberries. A linear relationship existed between ORAC and anthocyanin (r(xy) = 0.77) or total phenolic (r(xy) = 0.92) content. In general, blueberries are one of the richest sources of antioxidant phytonutrients of the fresh fruits and vegetables we have studied.
Article
The French have one of the lowest incidences of coronary heart disease in the Western world despite a diet with a relatively high fat content. This phenomenon that has puzzled researchers worldwide for more than a decade is known as the 'French paradox' and has been linked to the high consumption of red wine in France. Red wine is rich in the complex polyphenols, the proanthocyanidins, and these compounds have recently attracted attention as potential cardiac-protective compounds. The present review summarizes the literature on proanthocyanidins with focus on their chemical structure, the occurrence, the daily intake from foods, the bioavailability and metabolism, and the evidence for a protective effect against cardiovascular diseases.