Vegetables antioxidant properties

NICOLI M c, ANESE M, PARPINEL M T (1999) Influence of processing on the antioxidant properties of fruit and vegetables , Trends Food Sci Technol, 10 (3) 94-100. 

Fruifs and vegetables also contain ofher bioactive substances such as polyphenols (including well-known pigments anthocyanins, flavonols) and non-provitamin A carotenoids (mainly lycopene, lutein, and zeaxanthin) that may have protective effects on chronic diseases. Polyphenols and carotenoids are known to display antioxidant activities, counteracting oxidative alterations in cells. Besides these antioxidant properties, these colored bioactive substances may exert other actions on cell signaling and gene expression. 

There is usually no need to supplement with specific vitamins. Patients should be encouraged to eat a well balanced diet and should also take a multivitamin and mineral supplement. Some clinicians recommend vitamins C and E for their antioxidant properties however, no significant improvements have been shown compared to placebo. Encourage patients to eat a diet rich in vitamin C and E (i.e., bright colored fruits and vegetables, nuts, and whole grains). Metabolism of levodopa may cause elevated homocysteine concentrations that... 

Lako J, Trenerry, VC, Wahlqvist M, Wattanapenpaiboon N, Sotheeswaran S and Premier R. 2007. Phytochemical flavonols, carotenoids and the antioxidant properties of a wide selection of Fijian fruit, vegetables and other readily available foods. Food Chem 101(4) 1727-1741. 

Zhou K and Yu L. 2006. Total phenolic contents and antioxidant properties of commonly consumed vegetables grown in Colorado. LWT Food Sci Technol 39(10) 1155—1162. 

The role of the antioxidant properties of vitamins C, E, and p-carotene in the prevention of cardiovascular disease has been the focus of several recent studies. Antioxidants reduce the oxidation of low-density lipoproteins, which may play a role in the prevention of atherosclerosis. However, an inverse relationship between the intake or plasma levels of these vitamins and the incidence of coronary heart disease has been found in only a few epidemiological studies. One study showed that antioxidants lowered the level of high-density lipoprotein 2 and interfered with the effects of lipid-altering therapies given at the same time. While many groups recommend a varied diet rich in fruits and vegetables for the prevention of coronary artery disease, empirical data do not exist to recommend antioxidant supplementation for the prevention of coronary disease. 

Carotenoids, present in fruits and vegetables, are widely believed to protect human health. In particular, some epidemiological studies have correlated the intake of carotenoid-rich fruits and vegetables with protection from some forms of cancer (4,5). This action is probably due to the carotenoids antioxidant properties rather than to their vitamin A activity. 

Similarly, Tarozzi et al. (2004) assessed the impact of cultivation practices, commercial processing, and storage of fruits and vegetables on phenolic antioxidants. They investigated the influence of commercial cold-storage periods on antioxidant properties of apples grown by organic or... 

In association with well-known health benefits related to the consumption of fruit- and vegetable-rich diets, research on the protective effects of plant-derived phenolic compounds (polyphenols) has developed notably in recent years. In particular, their antioxidant properties have been the objective of extensive research. However these phenolics are the target of an array of chemical reactions that, if confirmed to occur in vivo, would contribute to their health promoting effects. It is now emerging that both parent compounds and their metabolites produced after ingestion can regulate cell and tissue functions by both antioxidant and nonantioxidant mechanisms. This volume provides the latest evidence supporting these concepts. 

Flavonoids are a family of antioxidants found in fruits and vegetables as well as in popular beverages such as red wine and tea. Although the physiological benefits of flavonoids have been largely attributed to their antioxidant properties in plasma, flavonoids may also protect cells from various insults. Nerve cell death from oxidative stress has been implicated in a variety of pathologies, including stroke, trauma, and diseases such as Alzheimer s disease and Parkinson s disease. 

Indeed, food plant products can have other interesting functions than just being a source of energy such as, for instance, pharmaceutical properties. Compounds with antioxidant properties and with antiaging effects are brought by various vegetables (32). 

In addition, malic acid has chelating and antioxidant properties. It may be used with butylated hydroxytoluene as a synergist in order to retard oxidation in vegetable oils. In food products it may be used in concentrations up to 420 ppm. 

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