Anthocyanins health effects

Cyanidin is the most common anthocyanin in foods. In addition, anthocyanins are stabilized by the formation of complexes with other flavonoids (co-pigmentation). In the United States, the daily anthocyanin consumption is estimated at about 200 mg. Several promising studies have reported that consumption of anthocyanin-rich foods is associated with reductions of the risks of cancers - and atherosclerosis and with preventive effects against age-related neuronal and behavioral declines. These beneficial effects of anthocyanins might be related to their reported biological actions such as modulators of immune response and as antioxidants. Knowledge of anthocyanin bioavailability and metabolism is thus essential to better understand their positive health effects. 

Interest in the health effects of anthocyanins was piqued by the French paradox in which the mortality from cardiovascular disease was lower than that predicted from the intake of dietary saturated fatty acids. The beneficial effects were greater in association with alcohol taken in the form of wine suggesting that there may be a protective effect of other components of wine. Needless to say the wine industry was pleased with this research. 

The potential health effects of anthocyanins and flavonols has stimulated much research in this area but, in view of the chemical complexity of the plant extracts, we are a long way from determining the chemical compounds responsible for the wide variety of claims. Regardless, a colorant with associated health benefits is a very desirable situation from an industry point of view. This is a very active research area. 

Prior, R.L., Absorption and metabolism of anthocyanins potential health effects. Phytochemicals Mechanisms of Action, 4th International Phytochemical Conference, Phytochemicals Mechanisms of Action , Pomona, CA (October 21-22, 2002), 2004. 

Recently, anthocyanins have received less attention compared to other flavonoids despite their far-reaching health effects. Because berries might have occupied such a large part of early diets, our ancestors probably ate more anthocyanins when compared to our food intake. In fact, according to some researchers, we might be deficient in anthocyanins. When people understand the antioxidant potential of the phytochemicals, perhaps we could improve the deficiencies by taking them. In due-course, our daily common foods may give even more enjoyment to us. 

Prior RL (2004) Absorption and metabolism of anthocyanins potential health effects. In Meskin M, Bidlack WR, Davies AJ, Lewis DS, Randolph RK (eds) Phytochemicals mechanisms of action. CRC, Boca Raton, pp 1-19... 

Anthocyanins are water-soluble plant pigments responsible for the blue, purple, and red color of many plant tissues. The analysis of anthocyanins has become particularly important because of the numerous studies dealing with their potential health effects (Chen et al., 2009 Galvano et al., 2009 Varadinova et al., 2009 Woodward et al., 2009 de Pascual-Teresa et al., 2010 Knaup et al., 2009 Kokotkiewicz et al., 2010 Krikorian et al., 2010 Takikawa et al., 2010). However, the many different structures of anthocyanins and their complex chemistry have provided challenges in their analysis. 

It is critical to recognize the high reactivity and low stability of anthocyanins in the selection of methods of extraction and quantitation in the analysis of anthocyanins. An analysis of processed samples containing anthocyanins for polymeric color as well as monomeric anthocyanins is recommended in nutrition studies until we better understand any health effects (positive or negative) of the compounds that are part of the mix measured as polymeric color. ... 

This review will focus on the food content of anthocyanins, their absorp-tion/metabolism, and reports of potential beneficial health effects. Other reviews have been published that deal more with the chemistry of anthocyanins. - ... 

Although these are the major polyphenolics in berries, it may or may not be these particular components that are responsible for some of the health effects attributed to berries. In our present scientific environment, it is common to take the reductionist point of view, where researchers study single compounds as new therapeutic agents, but in reality, it may be that the end resnlt is based on hundreds of distinct molecules. Although this idea presents a hnge challenge scientifically, it may not be as far-fetched today as it once seemed. In the following section, we will discuss some of the literature that indicates possible involvement of at least the anthocyanins and pro-anthocyanidins in prevention of cancers. 

In the case of the gut, it is not yet clear if these local effects are caused by the original anthocyanin or by the metabolites formed by the colonic microflora. The formation of these degradation products may be involved in the protective action of anthocyanins against colon and rectum cancer. This is an area of research that is growing very recently due to the potential of this kind of the interaction bacteria-anthocyanin as an explanation for the final health effect encountered for this group of polyphenols. 

One of the main reasons for this lack of concretion is the complexity of plant matrices, whose diversified secondary metabolism includes a vast number of different compounds with close structures that can be hard to identify. Some of these families with a well-documented bibliography related to health effects comprise alkaloids, phenolic compounds (including phenolic acids, stilbenes like resveratrol, or flavonoids such as anthocyanins, procyanidins, or isoflavones), terpenoids, carotenoids, sulfur compounds (such as glucosinolates and isothiocyanates), etc. Their presence and amount in the plant source depend on multiple factors including variety, organ of the plant, soil, sun exposure, climate, or even ways of cultivation. 

In the case of anthocyanins, this is even more complex as they coexist under different structural forms at physiological pH. Extensive knowledge of the bioavailability of anthocyanins is thus essential if their health effects are to be understood (Fig. 79.5). 

On the other hand, in vivo studies have increased the awareness of anthocyanin tissue distribution, have given an insight about anthocyanin biokinetic behavior, and allowed to relate anthocyanin consumption with several beneficial health effects. Even so, these types of studies have some limitations given that, generally, there is not a mechanistic approach about the movement of anthocyanins through the cells or the pathways responsible for the biological effects observed. 

A high ntrmber of bioactive corr ormds have been identified in Cornus fruits, including ascorbic acid, phenolic compotmds, anthocyanins, flavonoids, iridois, terpenoids, compoimds that exert health effects especially by acting as potent antioxidants. 

Phenolic compounds from fruits contribute to their quality, nutritional value, color, taste, aroma and flavor. They are also known to provide the beneficial health effects of many fruits. Phytophenols comprise a wide variety of compoimds, divided into several classes hydroxy-acids, anthocyanins, flavonoids, lignans, and taimins. 

The purpose of this chapter is to provide an overview of our present knowledge about the health benehts of pigments, particularly their effects on chronic diseases. We examine the effects of lipophilic (carotenoids, chlorophylls) and hydrophilic pigments (anthocyanins and flavones-flavonols), and curcumin. Descriptive and mechanistic studies are reviewed in regard to common chronic diseases. 

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