Year: 2012
Type: article
Abstract: Carotenoids are non-polar compounds which impart the yellow, orange, and red hues to a number of commonly consumed fruits and vegetables.Some carotenoids, like β-carotene, serve as an important source of provitamin A in the human diet.In contrast, consumption of the carotenoid lycopene has been associated with a reduced risk of developing cardiovascular disease and cancer.Finally, the consumption of lycopene, in addition to the carotenoids phytoene and phytofluene, has been associated with a reduced severity of erythema after ultraviolet light exposure.A better understanding of the absorption, metabolism, and bioefficacy of these compounds is important for making future nutritional recommendations to ensure adequate vitamin A status and reduce the risk of developing specific diseases.Tomatoes have the unique ability to synthesize a variety of carotenoids, and novel varieties which accumulate β-carotene, lycopene, phytoene, and phytofluene, were used in our studies.Our first aim was to determine if the consumption of a β-carotene-rich tomato sauce or carrots (containing both β-carotene and α-carotene) with lipid would enhance the delivery of greater quantities of vitamin A as compared to consuming the same carotene rich food without lipid.This objective was accomplished by first developing an HPLC-MS/MS method to separate and identify the carotenes and fat soluble vitamins in the test meal, and then quantitating the immediate post-prandial plasma concentrations of iii β-carotene and vitamin A metabolites after healthy subjects consumed a meal with or without lipid-rich avocado in combination with a serving of tomato sauce.Consumption of the sauce with lipid-rich avocado increased β-carotene levels by 2.3 fold and increased retinyl esters (i.e.vitamin A) by 4.5 fold as compared to the same sauce meal without avocado.An important step in elucidating the potential bioactivity of lycopene is a better understanding of its metabolism in the human body.One approach in determining if and how lycopene is metabolized is to identify the oxidative or enzymatic products of lycopene.Our second aim was to determine whether oxidative products of lycopene are present in raw and processed tomatoes and other lycopene containing foods, in addition to blood plasma of humans who have consumed processed tomato juice.Numerous lycopene metabolites were identified and quantified in raw foods and food products containing lycopene.In addition, these lycopene metabolites were also identified and quantified in the blood plasma of healthy humans who had consumed a high-lycopene tomato juice for 8 weeks.Finally, the consumption of tomato paste and tomato oleoresin containing lycopene, phytoene, and phytofluene has been associated with reduced severity of erythema after ultraviolet light exposure in humans.Our third aim was to determine if the consumption of tangerine tomatoes, containing higher levels of the ultraviolet light absorbing carotenoids phytoene and phytofluene, would: 1) result in the accumulation of lycopene, phytoene, and phytofluene in a mouse model, and 2) reduce the incidence or severity of acute ultraviolet B irradiation-induced skin damage.An immunocompetent,
Author: Rachel E. Kopec
Institution: The Ohio State University
Language: English
Subfield: Biochemistry
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1488072590