Antioxidant hydroxycinnamic acid

Fig. (4). General structures of antioxidant hydroxycinnamic acid derivatives.

There are also more complex hydroxycinnamic acids in cereals and other members of the Poaceae. These are cell wall-bound mono-, di- and tri-ferulates. Although they appear to have significant antioxidant activity, their bioavailability (release from cell walls and subsequent absorption in humans) is very low. 

A major group of citrus compounds interacting with drugs are phenolics, which include hydroxycinnamic acids, flavonoids such as flavanones, fla-vones, and flavonols, and anthocyanins, as well as coumarins (Table 1, Fig. 1) (30). Many of these phenolic compounds have been shown to have antioxidant and anticancer properties that may play an important role in cancer prevention, but also in prevention of other chronic diseases such as coronary heart disease, gout, and arthritis (58 60). 

Ananas comosus (L.) Merrill Feng Li (leaf) Ergosterol peroxide, ananasic acid, 5 -stigmautena-3 (3,7d-diol, 3,4-dihydroxy cinnamic acid, 4-hydroxycinnamic acid, bromelin, vitamins.57 Antioxidant activity, for digestion, lower blood pressure, anticancer. 

The comparison in terms of preservation of the total antioxidant activity and of the bioactive antioxidant components of the juice (ascorbic acid, anthocyanins, hydroxycinnamic acids, flavanones) demonstrates that this integrated membrane... 

For many centuries, cinnamon and its essential oil have been used as preservatives in food, due to the antioxidant property of cinnamon. Deterioration of food is due to lipid peroxidation. In vivo lipid peroxidation causes tissue damage, which can lead to inflammatory diseases. Phenolic compounds, such as hydroxy cinnamalde-hyde and hydroxycinnamic acid, present... 

There is a growing interest in naturally occurring phenolic compounds that display biological antioxidant properties such as -hydroxycinnamic acid, ferulic zcid, caffeic acid/ and curcumin which are ubiquitous in plant food. It has been demonstrated that the interaction of the oxidizing OH adduct of DNA, poly-A and poly-G with hydrox-ycinnamic acid derivatives proceed via electron transfer. Cinnamic acid derivatives have been shown to be able to scavenge superoxide, peroxyl, and hydroxyl radicals. 

High Nutrient Content protein, prebiotic fiber, antioxidant A-C-E vitamins (diminished by heating), B vitamins, dietary minerals High Phytochemical Content carotenoids (beta-cryptoxanthin, beta-carotene) polyphenols (anthocyanins, particularly delphinidin and cyanidin glycosides and rutinosides, catechins, proanthocyanidins, chlorogenic acid, quercetin, hydroxycinnamic acid)... 

Water stress may upregulate the phenyl propanoid synthesis pathway and hence enhance the level of anthocyanin and hydroxycinnamic acids contributing to elevated levels of antioxidants in sweet potato roots (Philpott et al. 2003). Drought and cold stresses elevated (-)-epicatechin and some flavonoid levels in hawthorn... 

Similarly, the phenolic antioxidants p-coumaric acid, ferulic acid, curcumin, and caffeic acid, which are found in coriander (as well as members of the Labiatae family, see below), inhibit the formation of 3-nitrotyrosine in vitro and may prevent lipid peroxidation in vivo [14, 15]. Caffeic acid and other hydroxycinnamic acids have also been found to exert an inhibitory effect on LDL oxidation, a known risk factor for CHD [16]. 

Important natural antioxidants in frying oils are tocopherols and tocoMenols. Other antioxidants, such as derivatives of p-hydroxybenzoic and hydroxycinnamic acid, hydroxytyrosol, and lignans, are also present in certain oils (Boskou, 1999 Carlos-Espin et al., 2000). 

Other antioxidants retained in heated oils enhance the stability of a-tocopherol and reduce losses in free radical scavenging activity. Such antioxidants include sinapic acid in rapeseed oil (Carlos-Espin et al., 2000) sesamol, sesamol dimers, and sesaminol in sesame seed oil and hydroxycinnamic acids and hydroxytyrosol in olive oil (Boskou, 1999 Pellegrini et al., 2001). 

Herrmann, K. (1990) Significance of hydroxycinnamic acid compounds in food I. Antioxidant activity - Effects on the use, digestibility and microbial spoilage of food. Chem. Mikrobiol Technol. Lebensm. 12, 137-144. 

Hydroxycinnamic acid derivatives have shown antioxidant and anti-inflammatory properties in vivo and in vitro. They contribute to DNA protection and help to prevent Alzheimer s disease [64, 65]. However, data are still too limited for an informed assessment of hydroxycinnamics [49]. 

Table 3.40. Relative antioxidative activity (RAA) of flavonoids, cumarins and hydroxycinnamic acids ...

ChoiS.W., LeeS.K., Kim E.O.,Oh J.H., Yoon K.S., Parris N., Hicks K.B., Moreau R.A. Antioxidant and antimelanogenic activities of polyamine conjugates from corn bran and related hydroxycinnamic acids. Journal of Agricultural and Food Chemistry, 55 3920-3925 (2007). 

Flow injection methodology was used to estimate the total phenolic content of wine using acidic potassium permanganate chemiluminescence detection by Costin et al. (2003). Simple phenolic compounds such as quercetin, rutin, catechin, epicatechin, ferulic acid, caffeic acid, gallic acid, 4-hydroxycinnamic acid, and vanillin were examined analytically with chemiluminescence. Analysis of 12 different wines showed that detection limits were 2 x 10 M for caffeic acid, 3 x 10 M for ferulic acid, and 5 x 10 M for gallic acid. Comparison of the results of the chemiluminescence methodology and other total phenol/antioxidant assays showed that their correlation was good. Chemiluminescence... 

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