Lycopene properties

In addition, Montenegro et al., (2007) determined that the photosensitized RF-mediated degradation of vitamins A, D3, and RF itself in skimmed milk was strongly reduced by the addition of small amounts of lycopene-gum arabic-sucrose microcapsules, prepared by spray-drying. Under these conditions, the bulk properties of the skimmed milk were unmodified. The main photoprotection mechanism of the milk vitamins was the efficient quenching of the 3Rf by the protein moiety of GA. Small contributions (<5%) to the total photoprotection percentage was due to both inner filter effect and 1O2 quenching by the microencapsulated lycopene. 

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. 

Rao, A.V. and Agarwal, S., Bioavailability and in vivo antioxidant properties of lycopene from tomato products and their possible role in the prevention of cancer, Nutr. Cancer, 3, 199, 1998. 

Supercritical fluid extraction (SEE) is another modern separation technology usually employed to extract lipophilic compounds such as cranberry seed oil, lycopene, coumarins, and other seed oils. Anthocyanins generally and glycosylated anthocyanins in particular were considered unsuitable for SEE due to their hydrophilic properties, since SEE is applicable for non-polar analytes. However, a small amount of methanol was applied as co-solvent to increase CO2 polarity in anthocyanin extraction from grape pomace. New applications of SEE for anthocyanin purification have been reported for cosmetic applications from red fruits. ... 

Ray, K. and T. N. Mishra. 1997. Photophysical properties of lycopene organized in Langmuir-Blodgett films Formation of aggregates. J. Photochem. Photobiol A 107 201-205. 

Carotenoids are a class of lipophilic compounds with a polyisoprenoid structure. Most carotenoids contain a series of conjugated double bonds, which are sensitive to oxidative modification and cis-trans isomerization. There are six major carotenoids (ji-carotenc, a-carotene, lycopene, P-cryptoxanthin, lutein, and zeaxanthin) that can be routinely found in human plasma and tissues. Among them, p-carotene has been the most extensively studied. More recently, lycopene has attracted considerable attention due to its association with a decreased risk of certain chronic diseases, including cancers. Considerable efforts have been expended in order to identify its biological and physiochemical properties. Relative to P-carotene, lycopene has the same molecular mass and chemical formula, yet lycopene is an open-polyene chain lacking the P-ionone ring structure. While the metabolism of P-carotene has been extensively studied, the metabolism of lycopene remains poorly understood. 

In summary, lycopene must have some specific effect on unknown cellular processes that control the modulation of multiple pathways. General properties, such as antioxidation or pro-oxidation, are unlikely to explain these effects. Since the activation, silencing or loss of pathway control is different for each cell type and its degree of transformation, we do not have enough information to predict whether lycopene may be beneficial or detrimental under different circumstances in various prostate cell lines and in the different stages of prostate cancer. 

Lycopene is a carotenoid with anticancer properties. To improve the production of lycopene by increasing the IPP flux in an engineered E. coli, the dxs gene was overexpressed and enhanced lycopene production was obtained [45]. In another example, the native promoters of DXP pathway genes in the E. coli chromosome were replaced with the strong bacteriophage T5 promoter (PTs), and the increase in isoprenoid precursors resulted in improved /3-carotene production (with a titer of 6 mg/g dry cell weight) [44]. 

Shi J and Le Maguer M. 2000. Lycopene in tomatoes chemical and physical properties affected by food processing. Crit Rev Food Sci Nutr 40(1) 1—42. 

Consumer acceptance of fresh and processed fruits and vegetables is influenced by product appearance, flavor, aroma, and textural properties. Color is a key component that influences a consumer s initial perception of fruit and vegetable quality. Lycopene is the principal carotene in tomato fruit that imparts color. Analytical and sensory... 

The antioxidant system in humans is a complex network composed by several enzymatic and nonenzymatic antioxidants. In addition to being an antioxidant, lycopene also exerts indirect antioxidant properties by inducing the production of cellular enzymes such as superoxide dismutase, glutathione S-transferase, and quinone reductase that also protect cells from reactive oxygen species and other electrophilic molecules (Goo and others 2007). 

The structures of four of the synthetic carotenoids (beta-carotene, canthaxanthin, beta-apo-8 -carotenol, beta-apo-8 -carotenoic acid) are shown in Fig. 8.2. By virtue of their conjugated double bond structure, they are susceptible to oxidation but formulations with antioxidants were developed to minimize oxidation. Carotenoids are classified as oil soluble but most foods require water soluble colorants thus three approaches were used to provide water dispersible preparations. These included formulation of colloidal suspensions, emulsification of oily solutions, and dispersion in suitable colloids. The Hoffman-LaRoche firm pioneered the development of synthetic carotenoid colorants and they obviously chose candidates with better technological properties. For example, the red canthaxanthin is similar in color to lycopene but much more stable. Carotenoid colorants are appropriate for a wide variety of foods.10 Regulations differ in other countries but the only synthetic carotenoids allowed in foods in the US are beta-carotene, canthaxanthin, and beta-8-carotenol. 

Carotenoids are sensitive to heat, light, acid, oxygen and chemicals. They may react in various ways during the process of isolation. The most important change is the formation of cis-isomers. Lycopene is said to form 1056 isomers (36), each with different properties. In some cases, cis-isomers separate more easily than carotenoids that differ by rearrangement of a double bond, i.e., zeaxanthin and lutein. However, a mixture of isomers can often be identified by their failure to crystallize and to give sharp separations on chromatographic columns. 

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. 

Since lycopene lacks the (3-ionic ring structure, unlike (3-carotene, it lacks provitamin A activity. The biological activity of lycopene is thought to be primarily due to its antioxidant properties. However, other mechanisms, such as facilitating gap junction communication (GJC) (Aust et al, 2003 Heber, 2002 Wertz et al, 2004 Zhang et al, 1991, 1992), stimulation of the immune system (Chew and Park, 2004 Heber, 2002 Heber and Lu, 2002 Kim et al, 2004 Wertz et al, 2004), endocrine-mediated pathways... 

Source Lycopene content of tomato products Its stability, bioavailability and in vivo antioxidant properties. Reprinted from Journal of Medicinal Food. 2001 4, pp. 9-15 by permission of Mary Ann Liebert, Inc., Publishers. 

Antioxidant properties of lycopene isomers as indicated by their ionization potential... 

FIG. 3 Stability and antioxidant properties of lycopene isomers (Chasse et al.9 2001). 

The role of lycopene in bone health to date is based on its potent antioxidant properties, the well-known role of oxidative stress in bone health, and the limited reported studies on the effects of lycopene in bone cells in culture. Therefore, in order to understand the role that lycopene can play in bone health, we have included a review of the reported studies on the role of oxidative stress in bone health and bone cells. 

Low bone density is also associated with oxidative stress in lower species. Thus, in ovariectomized rats melatonin has a bone-protective effect, which depends in part on its free radical-scavenging properties (Cardinali et al., 2003). A mouse model that has been used to study the role of ROS in age-related disorders including osteoporosis is the accelerated mouse-senescence-prone P/2 (SAM-P/2) that generates increased oxygen radicals (Hosokawa, 2002 Udagawa, 2002). This model could be very useful in studying the role of lycopene in osteoporosis. 

Jain, C.K., Agarwal, S., and Rao, A.V. 1999. The effect of dietary lycopene on bioavailability, tissue distribution, in-vivo antioxidant properties and colonic preneoplasia in rats. Nutr. Res. 19, 1383-1391. 

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