Tomato lycopene

Agarwal, S. and Rao, A.V., Tomato lycopene and low density lipoprotein oxidation a human dietary intervention study. Lipids, 33, 981, 1998. 

Giovannucci, E. 2002. A review of epidemiologic studies of tomatoes, lycopene, and prostate cancer. Exp Biol Med (Maywood) 227(10) 852-859. 

Population studies associate tomato consumption with reduced risk to prostate cancer. The most positive associations have come from cohort studies performed before the prostate-specific antigen (PSA)-screening era, and these studies have suggested that the tomato/lycopene effect was the strongest for clinically relevant prostate cancers (Giovannucci 2007). Small human studies have shown in vivo antioxidant effects for tomato products but evidence for lycopene alone is weak (Chen et al. 2001, Porrini and Riso 2000, Riso et al. 2004, Zhao et al. 2006). Animal and tissue culture studies have been... 

Giovannucci E and Clinton SK. 1998. Tomatoes, lycopene, and prostate cancer. Proc Soc Exp Biol Med 218(2) 129—139. 

The major source of lycopene is tomato products but it also occurs in water melons, guavas, pink grapefruit, and in small quantities in at least 40 plants.14 The structure of lycopene is shown in Fig. 8.2. It is a long chain conjugated hydrocarbon and its structure suggests that it would be easily oxidized in the presence of oxygen and isomerized to cis compounds by heat. Both of these reactions occur in purified solutions of lycopene but in the presence of other compounds normally present in tomatoes, lycopene is more stable. Actually the absorption of lycopene in the human gut is increased by heat treatment probably because the breakdown of the plant cells makes the pigment more accessible. Preparations from tomatoes are widely used in pizza, pasta, soups, drinks and any product compatible with the flavor and color of tomatoes. 

Vegetables are the most important source of carotenoids for humans. Most vegetables contain a variety of carotenoids [30,31]. Only carrots O-carotene) and tomatoes (lycopene) [32] contain one major carotenoid. However, even in these vegetables, several minor components can be identified, most of them geometrical isomers - structurally similar, but nevertheless totally different. For nutritional aspects, the level of these stereoisomers in nature is significant, because their biomedical properties can differ enormously. 

The relationship between tomatoes, lycopene, and other types of cancer are summarized as follows ... 

FIG. 6 Proposed mechanisms for the role of lycopene in chronic diseases. (Tomato lycopene and its role in human health and chronic diseases. Reprinted from CMAJ. 2000 163(6), pp. 739-744 by permission of 2000 CMA Media Inc.)... 

FIG. 12 Effect of dietary lycopene supplements on serum LDL oxidation (SS, spaghetti sauce TJ, tomato juice TO, tomato oleoresin). Bars with different letters are statistically different (p < 0.05). (Tomato lycopene and low density lipoprotein oxidation A human dietary intervention study. Reprinted from Lipids. 1988 33, pp. 981-984 by permission of AOCS Press.)... 

Tomato Lycopene isomers, P-carotene SFE C-30 MeOH-H20- MTBE HPLC/PAD (285, 347, 450 nm) 40... 

Coenzyme QIO is a powerful antioxidant naturally occurring in the mitochondria of myocardium, and it is an electron carrier in the mitochondrial synthesis of ATP. Patients with heart failure have lower myocardial levels of coenzyme QIO, but supplementation has been demonstrated to have variable benefits in randomized controlled trials. One meta-analysis on the use in congestive heart failure showed improvements in stroke volume, ejection fraction, cardiac output, cardiac index, and end diastolic volume index. " Another antioxidant associated with beneficial effects in cardiac patients is lycopene, a natural constituent of tomatoes. Lycopene is the major carotenoid found in human serum, and epidemiological studies have indicated an effect of dietary supplementation in reducing heart disease. Few dietary interventions have been reported one study showed a mild but significant hypocholesterolemic effect, and another showed a significant reduction in LDL oxidation. " Animal studies show an antiatherogenic effect of DHEA, and a review of the clinical trials and studies on DHEA in males with coronary heart disease reported a favorable or neutral effect. Plasma levels of DHEA are decreased in patients with chronic heart failure in proportion to its severity. ... 

Problem 9.19 The yellow plant pigments / -, and y-caronne, and the red pigment of tomatoes, lycopene, aie converted into Vitamin A in the liver. All four have the molecular formula Upon catalytic hydrogenation, - and -carotene... 

Lycopene synthesis in the rin mutant was enhanced by high 02 in the presence of 10 ppm ethylene (Frenkel and Garrison, 1976). On the other hand, ethanol inhibits ripening and the synthesis of tomato lycopene (Saltveit and Mencarelli, 1988). In addition, Sheehy et al. (1988) found that a reduction in polygalacturonase did not affect biosynthesis of lycopene. Lampe and Watada (1971) and Mohr (1979) pointed out that the lycopene content in tomato fruits may be increased by improving the practices at times of selection of varieties, fertilization and harvest. 

Tomato lycopene and other carotenoids have been used as natural food constituents for a long time without toxicological considerations, in the same manner as other vegetable and fruit products. Lack of sound information regarding toxicology and bioavailability data limits the development of food safety regulations. Further studies are necessary to provide toxicological evaluation of lycopene and information on how lycopene interacts with other constituents. 

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