Antioxidants in tomatoes

GERBER M (2000) The Antioxidants in Tomatoes and Tomato Products, Report of a European Commission Concerted Action FAIR CT 97-3233, France. 

Rousseaux, M.C. et al., QTL analysis of fruit antioxidants in tomato nsing Lycoper-sicon pennellii introgression lines, Theoret. Appl. Genet. Ill, 1396, 2005. 

The observed associations between folate, antioxidant vitamins, and cardiovascular disease may be confounded by other substances in fruits and vegetables, as the following examples of studies show Flavonoids (see Chapter 31) are naturally occurring, water-soluble antioxidants found widely distributed in vegetables, fruits, tea, and wine. There is an inverse relationship between flavonoids and decreased risk of coronary heart disease. Lycopene, the key antioxidant in tomatoes, shows an inverse association with myocardial infarctions. There is an inverse association between folate and cardiovascular disease. 

Grolier, R 2000. Tomato antioxidants and biosynthesis. In Summary of the White Book The Antioxidants in Tomatoes and Tomato Products and their Health Benefits, Amiton (ed.), Avignon Cedex, France, p. 6. 

Rousseaux M, Jones C, Adams D, Chetelat R, Bennett A, Powell A (2005) QTL analysis of fruit antioxidants in tomato using Lycopersicon pennellii introgression lines. Theor Appl Genet 111 1396-1408... 

George, B., Kaur, C., Khurdiya, D. S., Kapoor, H. C. (2004). Antioxidants in tomato (Lycopersium esculentum) as a function of genotype. Food Chemistry, 84,45-51. 

Grolier, R, Bartholin, G., Broers, L. et al. (1999) Composition of tomatoes and tomato products in antioxidants. In R. BUton, M. Gerber, R Grolier et al. (eds). The White Book on Antioxidants in Tomatoes and Tomato Products and Their Health Benefits. Tomato News, CMITI, Avignon, pp. 1-104. 

In inner layers, changes are much the same as during boiling. Tocopherols and tocotrienols present in wheat and rye are partially destroyed during baking. In ordinary wheat bread, losses of a-tocopherol amount to about 25%, but in the case of rye bread, prepared by traditional technology, a loss of about 50% was reported (Piironen et al, 1987). Losses of natural antioxidants in coffee brews and tomato puree were also observed (Nicoli et al, 1997). 

Abushita, A.A., Daood, H.G., and Biacs, P.A., Change in carotenoids and antioxidant vitamins in tomato as a function of varietal and technological factors, J. Agric. Food Chem., 48, 2075, 2000. 

Abushita AA, Hebshi EA, Daood HG and Biacs PA. 1997. Determination of antioxidant vitamins in tomatoes. 

Lycopene, the predominant carotenoid in tomatoes (Solatium lycopersicum), exhibits the highest antioxidant activity and singlet oxygen quenching ability of all dietary... 

Lycopene is a red pigment found in tomatoes, watermelon, papaya, guava, and pink grapefruit. An antioxidant like vitamin E, lycopene contains many conjugated double bonds—double bonds separated by only one single bond—that allow jt electron density to delocalize and give the molecule added stability. In Chapter 16 we learn about such conjugated unsaturated systems. 

The bioavailability of lycopene in tomato-based foods vs. that in fresh tomatoes increases even further when lycopene is consumed with oil. In studies by Stahl and Sies (1992, 1996), ingestion of tomato juice cooked in an oil medium resulted in a two- to threefold increase in lycopene serum concentrations 1 day after ingestion. An equivalent consumption of unprocessed tomato juice caused no rise in lycopene plasma concentration. This indicates that thermal pretreatment and an oil medium were beneficial for extracting lycopene into the lipophilic phase. Solubilization of lycopene in a lipophilic matrix is expected to considerably enhance its availability and its bioactivity. This is likely to boost its effectiveness as an antioxidant. However, this higher reactivity also renders lycopene more vulnerable to the detrimental effects of factors such as air, temperature and interactions with other components of the food. 

Lycopene oxidation products have been extensively studied by Khachik and coworkers [1, 30-33] two oxidative metabolites, 2,6-cyclolycopene-1,5-diols A and B, present in tomatoes at very low concentrations were identified in human serum, breast milk, and organs (prostate, lung, liver, colon, breast). Recently it has been suggested that the presence of these products may result from the in vivo antioxidation properties of lycopene, and they have been proposed as potential markers of oxidative stress [34]. 

Recent research also indicates an association between tomato consumption (fresh and processed) and protection against cardiovascular disease. Coronary heart disease (CHD) has a high prevalence in western countries and is increasing in Asian countries due to changes in socioeconomic conditions, lifestyle, and diet. The link between LDL oxidation and atherosclerosis is hypothesized to be the basis for a beneficial effect of antioxidants in general on the incidence of subclinical and clinical CHD. 

Li, H., Deng, Z., Wu, T., Liu, R., Loewen, S., and Tsao, R. 2012. Microwave-assisted extraction of phenolics with maximal antioxidant activities in tomatoes. Food Chem. 130 928-936. 

Giovinazzo G, D Amieo L, Paiadiso A, Bollini R, Sparvoli F, DeGara L (2005) Antioxidant metabolite profiles in tomato uit constitutively expressing the grapevine stilbene synthase gene. Plant Bioteehnol J 3 57-69... 

Giliberto L, Perrotta G, Pallara P, Weller JL, Fraser PD, Brantley PM, Fiore A, Tavazza M, Giuliano G (2005) Manipulatirai of the blue light photoreceptor cryptochrome 2 in tomato affects vegetative developmtait, flowering time, and Iruit antioxidant content. Plant Physiol 137 199-208... 

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