Lycopene processing effects

Takeoka, G.R., Processing effects on lycopene content and antioxidant activity of tomatoes, J. Agric. Food Chem., 49, 3713, 2001. 

In cell culture, lycopene is a highly oxidizable nonpolar hydrocarbon supplied in an aqueous medium and is incubated at body temperature for 12-72 h. The amount of intact lycopene or its oxidation products delivered to and absorbed by various cell types is an important factor to keep in mind when evaluating the effects of lycopene on various cellular processes. Before reviewing cell culture studies designed to characterize the effects of lycopene on prostate cell biology, the characteristics of prominent prostate cell lines, and the stability and uptake of lycopene by various prostate cell lines are reviewed. 

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. 

Re, R., Bramley, P.M., and Rice-Evans, C., Effects of food processing on flavonoids and lycopene status in a Mediterranean tomato variety. Free Radical Res., 36, 803, 2002. 

EFFECT OF PROCESSING ON LYCOPENE CONTENT OF TOMATO JUICE... 

Handelman et al., 1996). Alcohol consumption was also shown to alter serum lycopene levels (Brady et al., 1997). Other factors that influence the bioavailability of lycopene are its release from the food matrix due to processing, presence of dietary lipids, and heat-induced isomerization from the all-trans to cis conformation. They all enhance lycopene absorption into the body. Ingestion of cooked tomato juice in oil medium increased serum lycopene levels threefold whereas consumption of an equal amount of unprocessed juice did not have any effect (Stahl and Sies, 1992). 

This chapter provides an overview of lycopene bioavailability and the potential benefits of dietary lycopene on human health. Lycopene chemistry and its effect on functionality will be discussed, followed by the effects of processing on lycopene obtained from tomatoes. Finally, methods of analysis and of extraction from tomatoes are discussed. 

The present volume also addresses the issue of processing and its effects on the bioavailability of bioactives. It shows that processing of a functional food may have profound effects on specific health benefits it claims to deliver. As illustrated in Chapter 4, the physiological effects of lycopene are altered significantly during processing, primarily due to its isomerization and oxidation. Worth noting, however,... 

Kaur, D., Wani, A. A., Oberoi, D. P. S., and Sogi, D. S. (2008). Effect of extraction conditions on lycopene extractions from tomato processing waste skin using response surface methodology. Food Chem. 108, 711-718. 

Chapter 12 summarizes the role of dietary phytochemicals, especially those from fruits, herbs, and spices, in the prevention of cardiovascular disease. Chapter 13 is devoted to the effects and mecharusms of action of resveratrol, a polyphenolic phytoalexin that has received considerable publicity. The same is tine of lycopene, the topic of Chapter 14, which occurs in especially high levels in fresh and processed tomatoes. Consideration is given in Chapter 15 to the effects of oltipraz on phase 1 and 2 xenobiotic-metabolizing enzymes this draws together nutritional, clinical, and pharmacological investigation and provides some pointers for the future. These are elaborated upon in Chapter 16, which addresses research directions, challenges, and opportunities. 

The ability of lycopene to act as an antioxidant and scavenger of free radicals is frequently cited as the most likely mechanism that could account for the hypothesized beneficial effects on human health.Supporting this theory, protection against oxidative stress has been shown in parallel with a preferential destraction of lycopene relative to P-carotene in a study of human skin irradiated with ultraviolet (UV) light. Further, the ability of carotenoids to act as antioxidants has been hypothesized as the mechanism underlying the protection of the human retina from photooxidation, a process that over time can result in the pathologies of age-related macular degeneration (AMD) and cataracts. ... 

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