title: The proportion of lycopene isomers in human plasma is modulated by lycopene isomer profile in the meal but not by lycopene preparation.
abstract: Dietary lycopene consists mostly of the (all-E) isomer. Upon absorption, (all-E) lycopene undergoes isomerisation into various (Z)-isomers. Because these isomers offer potentially better health benefits than the (all-E) isomer, the aim of the present study was to investigate if the profile of lycopene isomers in intestinal lipoproteins is affected by the profile of lycopene isomers in the meal and by the tomato preparation. Six postprandial, crossover tests were performed in healthy men. Three meals provided about 70 % of the lycopene as (Z)-isomers, either mainly as 5-(Z) or 13-(Z), or as a mixture of 9-(Z) and 13-(Z) lycopene, while three tomato preparations provided lycopene mainly as the (all-E) isomer. Consumption of the 5-(Z) lycopene-rich meal led to a high (60 %) proportion of this isomer in TAG-rich lipoproteins (TRL), indicating a good absorption and/or a low intestinal conversion of this isomer. By contrast, consumption of meals rich in 9-(Z) and 13-(Z) lycopene isomers resulted in a low level of these isomers but high amounts of the 5-(Z) and (all-E) isomers in TRL. This indicates that the 9-(Z) and 13-(Z) isomers were less absorbed or were converted into 5-(Z) and (all-E) isomers. Dietary (Z)-lycopene isomers were, therefore, differently isomerised and released in TRL during their intestinal absorption in men. Consuming the three meals rich in (all-E) lycopene resulted in similar proportions of lycopene isomers in TRL: 60 % (all-E), 20 % 5-(Z), 9 % 13-(Z), 2 % 9-(Z) and 9 % unidentified (Z)-isomers. These results show that the tomato preparation has no impact on the lycopene isomerisation occurring during absorption in humans.
authors: Nestlé Research Center, Nestec Limited, PO Box 44, CH-1000 Lausanne 26, Switzerland. myriam.richelle@rdls.nestle.com
authors: Myriam
authors: M
authors: Richelle
authors: Pierre
authors: P
authors: Lambelet
authors: Andreas
authors: A
authors: Rytz
authors: Isabelle
authors: I
authors: Tavazzi
authors: Anne-France
authors: AF
authors: Mermoud
authors: Christine
authors: C
authors: Juhel
authors: Patrick
authors: P
authors: Borel
authors: Karlheinz
authors: K
authors: Bortlik
mesh_terms: D000328:Adult; D000975:Antioxidants / Q000378:metabolism* / Q000494:pharmacology; D001682:Biological Availability; D002338:Carotenoids / Q000378:metabolism* / Q000494:pharmacology; D004032:Diet; D005511:Food Handling / Q000379:methods*; D006801:Humans; D007408:Intestinal Absorption; D007413:Intestinal Mucosa / Q000378:metabolism*; D007536:Isomerism; D008074:Lipoproteins / Q000378:metabolism; D000077276:Lycopene; D018551:Solanum lycopersicum / Q000737:chemistry*; D008297:Male; D010936:Plant Extracts / Q000378:metabolism* / Q000494:pharmacology; D019518:Postprandial Period; D014280:Triglycerides / Q000378:metabolism; D055815:Young Adult
chemical_list: D000975:Antioxidants; D008074:Lipoproteins; D010936:Plant Extracts; D014280:Triglycerides; D002338:Carotenoids; D000077276:Lycopene