Anthocyanins

This book contains 20 articles published in Molecules that concern the color quality of food and wine, anthocyanin biosynthesis and regulation, anthocyanin composition and the biological properties of anthocyanin pigments

Recent Research on the Health Benefits of Blueberries and Their Anthocyanins

Awareness of the human health benefits of blueberries is underpinned by a growing body of positive scientific evidence from human observational and clinical research, plus mechanistic research using animal and in vitro models. Blueberries contain a large number of phytochemicals, including abundant anthocyanin pigments. Of their various phytochemicals, anthocyanins probably make the greatest impact on blueberry health functionality. Epidemiological studies associate regular, moderate intake of blueberries and/or anthocyanins with reduced risk of cardiovascular disease, death, and type 2 diabetes, and with improved weight maintenance and neuroprotection. These findings are supported by biomarker-based evidence from human clinical studies. Among the more important healthful aspects of blueberries are their anti-inflammatory and antioxidant actions and their beneficial effects on vascular and glucoregulatory function. Blueberry phytochemicals may affect gastrointestinal microflora and contribute to host health. These aspects have implications in degenerative diseases and conditions as well as the aging process. More evidence, and particularly human clinical evidence, is needed to better understand the potential for anthocyanin-rich blueberries to benefit public health. However, it is widely agreed that the regular consumption of tasty, ripe blueberries can be unconditionally recommended

Blueberry polyphenols increase lifespan and thermotolerance in Caenorhabditis elegans

The beneficial effects of polyphenol compounds in fruits and vegetables are mainly extrapolated from in vitro studies or short-term dietary supplementation studies. Due to cost and duration, relatively little is known about whether dietary polyphenols are beneficial in whole animals, particularly with respect to aging. To address this question, we examined the effects of blueberry polyphenols on lifespan and aging of the nematode, Caenorhabditis elegans, a useful organism for such a study. We report that a complex mixture of blue-berry polyphenols increased lifespan and slowed aging-related declines in C. elegans. We also found that these benefits did not just reflect antioxidant activity in these compounds. For instance, blueberry treatment increased survival during acute heat stress, but was not protective against acute oxidative stress. The blueberry extract consists of three major fractions that all contain antioxidant activity. However, only one fraction, enriched in proanthocyanidin compounds, increased C. elegans lifespan and thermotolerance. To further determine how polyphenols prolonged C. elegans lifespan, we analyzed the genetic requirements for these effects. Prolonged lifespan from this treatment required the presence of a CaMKII pathway that mediates osmotic stress resistance, though not other pathways that affect stress resistance and longevity. In conclusion, polyphenolic compounds in blueberries had robust and reproducible benefits during aging that were separable from antioxidant effects

Selected bioactivities of vaccinium berries and other fruit crops in relation to their phenolic contents

Antioxidant activity, urinary tract protective activity, and cardioprotective anti-platelet effects are among the bioactivities associated with dietary phenolics. These bioactivities were measured in vitro in fruit extracts from seven Vaccinium species and five non-Vaccinium species to determine their relationship to total phenolic content and to anthocyanin and proanthocyanidin content. Berries belonging to the genus Vaccinium were particularly high in antioxidant activity and urinary tract protective anti-adhesion activity, while anti-platelet activity varied among species. There was a positive relationship between antioxidant activity (using the oxygen radical absorbing capacity (ORAC) assay) and both the total phenolic (R2 = 0.76) and anthocyanin content (R2 = 0.43) of the fruit, although there was no relationship between ORAC and proanthocyanidin content. There were no relationships between anti-adhesion activity and total phenolic content, anthocyanin content, or proanthocyanidin content. Likewise, no relationships were observed between anti-platelet activity and total phenolic content, anthocyanin content, or proanthocyanidin content. These results suggest that while antioxidant properties are characteristic of all fruit phenolics, in vitro anti-adhesion and anti-platelet bioactivities may be due to less abundant phenolic subgroups.Peer reviewed: YesNRC publication: Ye

Selected bioactivities of vaccinium berries and other fruit crops in relation to their phenolic contents

Antioxidant activity, urinary tract protective activity, and cardioprotective anti-platelet effects are among the bioactivities associated with dietary phenolics. These bioactivities were measured in vitro in fruit extracts from seven Vaccinium species and five non-Vaccinium species to determine their relationship to total phenolic content and to anthocyanin and proanthocyanidin content. Berries belonging to the genus Vaccinium were particularly high in antioxidant activity and urinary tract protective anti-adhesion activity, while anti-platelet activity varied among species. There was a positive relationship between antioxidant activity (using the oxygen radical absorbing capacity (ORAC) assay) and both the total phenolic (R2 = 0.76) and anthocyanin content (R2 = 0.43) of the fruit, although there was no relationship between ORAC and proanthocyanidin content. There were no relationships between anti-adhesion activity and total phenolic content, anthocyanin content, or proanthocyanidin content. Likewise, no relationships were observed between anti-platelet activity and total phenolic content, anthocyanin content, or proanthocyanidin content. These results suggest that while antioxidant properties are characteristic of all fruit phenolics, in vitro anti-adhesion and anti-platelet bioactivities may be due to less abundant phenolic subgroups.Peer reviewed: YesNRC publication: Ye

Phenolics of Vaccinium berries and other fruit crops

The concentrations and profiles of phenolics of selected fruit crops common in the Western diet, including several Vaccinium species, were examined to better understand how these crops may be useful sources of phenolic phytochemicals. Vaccinium fruit had a high phenolic concentration compared to non-Vaccinium fruit. Some Vaccinium fruit were particularly rich in certain phenolic subgroups, especially anthocyanins and pro-anthocyanidins. Among the pro-anthocyanidin oligomers measured using fluorometric and mass spectroscopic detection, the trimers and tetramers were most abundant, while pro-anthocyanidins with a degree of polymerization greater than 8 were least abundant. As biomedical studies determine which phenolic structures are associated with particular bioactivities, information on the phenolic concentration and profile of selected species will be useful in developing specific uses for fruit crops in human health. Methods were compared to assess the usefulness of simpler versus more sophisticated means of phenolic analysis. The phenolic components of fruit extracts were purified approximately 20-fold, and not qualitatively altered, by C18 solid-phase extraction. However, fruit extracts obtained from C18 solid-phase extraction differed in their relative abundance of phenolic components. Colorimetric and HPLC-DAD measures of phenolic concentration were correlated (R2 = 0.79), as was pro-anthocyanidin concentration detected fluorometrically and by mass spectrometry (R2 = 0.44). Copyright \ua9 2007 Crown in the right of Canada and Society of Chemical IndustryPeer reviewed: YesNRC publication: Ye