Background: Lycopene is mainly provided in tomato and tomato products in Western diet. Among other factors the systemic availability of lycopene from natural sources is dependent on release from the cell matrix as achieved by food processing.
Aims of the study: The purpose of this study was to compare plasma concentration responses of total lycopene and its major isomers to dosing of the carotenoid as tomato juice, tomato soup or tablets containing synthetic lycopene.
Methods: Intake of lycopene rich food products was restricted throughout this randomized, parallel group study, including 6 volunteers per group. Following a 14 day lycopene depletion phase subjects ingested 20 mg of lycopene daily for 8 days as tomato juice, soup prepared from tomato paste or lycopene tablets. Lycopene plasma concentrations were monitored throughout the depletion and dosing phases and for 22 days post-dosing and kinetics were evaluated using both empirical and compartmental modelling.
Results: Irrespective of the lycopene treatment all-E lycopene was the predominant lycopene isomer, whereas 5-Z lycopene was the most abundant Z isomer. Plasma concentration response of total and all-E lycopene to dosing of the carotenoid in tablets and tomato soup was comparable but exceeded that of intake in tomato juice. No differences were noted in dose normalized 5-Z lycopene concentrations between groups. The estimates of efficient half-life were approximately 5 and 9 days for all-E and 5-Z lycopene, respectively.
Conclusions: The systemic availability of synthetic lycopene from a tablet formulation is comparable to that observed from processed tomatoes (soup from tomato paste) and superior to that from tomato juice. No differences were observed in disposition kinetics of natural and synthetic lycopene. The synthetic lycopene tablet formulation used in this investigation may be of value for future clinical investigations.