U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 Food Components and Health Laboratory: Beltsville, MD
 close



    Research

                    Research Projects
                                    Publications
                                    Collaborations
                                    News
                People

                    Staff Listing
                                    Careers


        


                    FCHL Home
                    About FCHL
                        News
                                    Documents
                                    Directions to FCHLSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home Northeast Area Beltsville, Maryland (BHNRC) Beltsville Human Nutrition Research Center Food Components and Health Laboratory Research Publications at this Location





- ARS National Programs
- Search for a scientific manuscript
- Search for a research project
- ARS Software
- Programs and Projects
- Collaborations
- Subjects of Investigation
- Publications

Title:   Author  item
                                            MORAN, NANCY - The Ohio State Universityitem
                                            Novotny, Janetitem
                                            CICHON, MORGAN - The Ohio State Universityitem
                                            RIEDL, KENNETH - The Ohio State Universityitem
                                            ROGERS, RANDY - University Of Illinoisitem
                                            GRAINGER, ELIZABETH - The Ohio State Universityitem
                                            SCHWARTZ, STEVEN - The Ohio State Universityitem
                                            ERDMAN, JOHYN - University Of Illinoisitem
                                            CLINTON, STEVEN - The Ohio State University
  Submitted to: Journal of Nutrition
                                    Publication Type: Peer Reviewed Journal
                                    Publication Acceptance Date: 11/2/2015
                                    Publication  Date: 2/1/2016
                                    Citation: Moran, N.E., Novotny Dura, J., Cichon, M., Riedl, K., Rogers, R., Grainger, E., Schwartz, S., Erdman, J., Clinton, S. 2016. Absorption and distribution kinetics of the 13C-labeled tomato carotenoid phytoene in healthy adults. Journal of Nutrition. 146:368-376.Interpretive Summary: Tomato intake has been thought to be protective against prostate cancer since a Harvard publication reported reduced incidence of prostate cancer in men who consumed tomato products.  A compound called lycopene, which is in the family of pigments called carotenoids, was first thought to be the active component.  However, another carotenoid called phytoene is found in much lesser amounts in tomatoes but accumulates to similar levels in body tissues.   The accumulation of this compound in body tissues despite its lower concentration in food suggests that the body may preferentially retain phytoene for health reasons.  To date, very little is known about the body’s ability to absorb and distribute phytoene, therefore we conducted a study with specially tagged phytoene so we could follow it through human metabolism to determine how well it is absorbed, stored, and eliminated.  Four adults consumed the tagged phytoene and provided blood samples for six weeks after dosing.  The resulting data showed that the intestinal absorption of phytoene is approximately double that of the more common tomato carotenoid lycopene.  Further, the elimination of phytoene happens more than twice as slowly as lycopene.  As the roles of phytoene and lycopene are more clearly defined, dietary guidance regarding tomato, lycopene, and phytoene intakes will become more reliable.  These results will be useful to scientists and health practitioners.
                                Technical Abstract: Phytoene is a tomato carotenoid which may contribute to the apparent health benefits of tomato consumption. While phytoene is a less prominent tomato carotenoid than lycopene, it is a major carotenoid in various human tissues. Phytoene distribution to plasma lipoproteins and tissues differs from lycopene, suggesting the kinetics of phytoene and lycopene differ.  The objective of this study was to characterize the kinetic parameters of phytoene absorption, distribution, and excretion in adults, to better understand why biodistribution of phytoene differs from lycopene.  Four adults (2 males, 2 females) maintained a controlled phytoene diet (1-5 mg per day) for 42 days. On day 14, each consumed 3.2 mg 13C-phytoene, produced using tomato cell suspension culture technology.  Blood samples were collected at 0, 1-15, 17, 21, and 24 h and 2, 3, 4, 7, 10, 14, 17, 21, and 28 d post 13C-phytoene consumption. Plasma unlabeled and labeled phytoene concentrations were measured by UPLC-MS, and data were fit to a 7-compartment carotenoid kinetic model using WinSAAM 3.0.7 software.  Subjects were compliant with a controlled phytoene diet, consuming 2.5+/-0.6 mg per day, resulting in average unlabeled plasma phytoene concentrations of 71+/-14 nmol per L. A maximal plasma 13C-phytoene concentration of 55.6+/-5.9 nM was achieved 19.8+/-9.2 h after consumption, and the plasma half-life was 2.3+/-0.2 d. Compared to previous results for lycopene, phytoene bioavailability was nearly double at 58+/-19%, the clearance rate from chylomicrons was slower, and the rate of deposition into and utilization by the slow turnover tissue compartment were nearly 3 times greater.  Though only differing from lycopene by four double bonds, phytoene exhibits markedly different kinetic characteristics in human plasma, providing insight into metabolic processes contributing to phytoene enrichment in plasma and tissues compared to lycopene.


Return to top


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov