TY - JOUR A1 - Wiese, Stefanie A1 - Esatbeyoglu, Tuba A1 - Winterhalter, Peter A1 - Kruse, Hans-Peter A1 - Winkler, Stephanie A1 - Bub, Achim A1 - Kulling, Sabine E. T1 - Comparative biokinetics and metabolism of pure monomeric, dimeric, and polymeric flavan-3-ols: A randomized cross-over study in humans JF - Molecular nutrition & food research : bioactivity, chemistry, immunology, microbiology, safety, technology N2 - Scope: Flavan-3-ols are abundant polyphenols in human nutrition and are associated with beneficial health effects. The aim of this study was to comparatively investigate the metabolic fate of (-)-epicatechin, procyanidin B1, and polymeric procyanidins in a randomized cross-over study in humans. Methods and results: Parent compounds, conjugates, and microbial metabolites were determined in plasma, urine, and faeces by HPLC-MS and GC-MS/MS. Glucuronidated, sulfated, and methylated (-)-epicatechin and 5-(3',4'-dihydroxyphenyl)-valerolactone were the dominant metabolites in blood and urine. In addition, minor amounts of procyanidin B1 and 4-hydroxy-5-(3',4'-dihydroxyphenyl) valeric acid and their conjugated metabolites were detected. The formation of 5-(3',4'-dihydroxyphenyl)-valerolactone and 4-hydroxy-5-(3',4'-dihydroxyphenyl) valeric acid varied largely between individuals as well as with the degree of polymerization of flavan-3-ols. Monomer units were not detectable in plasma or urine after procyanidin B1 and polymeric procyanidin intake. No correlation was found between the intake of flavan-3-ols and the occurrence of phenolic acids in blood and urine or the phenolic compound profiles in faeces. Conclusion: In addition to conjugated metabolites derived from the absorption of monomeric flavan-3-ols, 5-(3',4' -dihydroxyphenyl)-valerolactone represents an important in vivo metabolite of (-)-epicatechin and procyanidin B1 produced by the gut microbiota. KW - Bioavailability KW - Catechins KW - Drug metabolism KW - Microbial degradation KW - Procyanidins Y1 - 2015 U6 - https://doi.org/10.1002/mnfr.201400422 SN - 1613-4125 SN - 1613-4133 VL - 59 IS - 4 SP - 610 EP - 621 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Frede, Katja A1 - Henze, Andrea A1 - Khalil, Mahmoud A1 - Baldermann, Susanne A1 - Schweigert, Florian J. A1 - Rawel, Harshadrai Manilal T1 - Stability and cellular uptake of lutein-loaded emulsions JF - Journal of functional food N2 - The carotenoid lutein can improve human health. Since only a fraction is absorbed from food, lutein supplementation might be recommended. Emulsions could be good carrier systems to improve the bioavailability of lutein. Six different emulsifier compositions were used in this study to prepare lutein-loaded emulsions: beta-lactoglobulin, beta-lactoglobulin/lecithin, Biozate 1, Biozate 1/lecithin, Been 20 and Tween 20/lecithin. The droplet size, resistance to creaming, lutein stability, cytotoxicity and lutein uptake by HT29 cells were investigated. The whey protein beta-lactoglobulin, the whey protein hydrolysate Biozate 1 and the combination with lecithin brought the most promising results. The small droplet sizes and resistance to creaming were an indication of physical stable emulsions. Furthermore, these emulsifiers prevented oxidation of lutein. The choice of emulsifier had a strong impact on the uptake by HT29 cells. The highest lutein absorption was observed with the combination of Biozate 1 and lecithin. KW - Lutein KW - Emulsion KW - Whey protein KW - Stability KW - Bioavailability Y1 - 2014 U6 - https://doi.org/10.1016/j.jff.2014.03.011 SN - 1756-4646 VL - 8 SP - 118 EP - 127 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Khalil, Mahmoud A1 - Raila, Jens A1 - Ali, Mostafa A1 - Islam, Khan M. S. A1 - Schenk, Regina A1 - Krause, Jens-Peter A1 - Schweigert, Florian J. A1 - Rawel, Harshadrai Manilal T1 - Stability and bioavailability of lutein ester supplements from Tagetes flower prepared under food processing conditions JF - Journal of functional food N2 - Tagetes spp. belongs to the Asteraceae family. It is recognized as a major source of lutein ester (lutein esterified with fatty acids such as lauric, myristic and palmitic acids), a natural colorant belonging to the xanthophylls or oxygenated carotenoids. Four species of Tagetes flower (Tagetes tenuifolia, Tagetes erecta, Tagetes patula, and Tagetes lucida) were used to extract lutein and lutein esters with three different methods. The results showed that T. erecta, type "orangeprinz", is the richest source of lutein esters (14.4 +/- 0.234 mg/g) in comparison to other Tagetes spp. No significant differences between extractions of lutein esters with medium-chain triacylglycerols (MCT) oil, orange oil or solvent (hexane/isopropanol) could be observed. MCT oil also improved stability of lutein esters at 100 degrees C for 40 min. Emulsification of MCT oil improved the stability of lutein ester extract against UV light at 365 nm for 72 h. Finally, an emulsion was prepared under food processing conditions, spray dried and its bioavailability investigated in a preliminary human intervention study. The results show a lower resorption, but further data suggest improvements in implementation of such supplements. (c) 2012 Elsevier Ltd. All rights reserved. KW - Tagetes KW - Lutein ester KW - Emulsion KW - Stability KW - Whey protein KW - Bioavailability Y1 - 2012 U6 - https://doi.org/10.1016/j.jff.2012.03.006 SN - 1756-4646 VL - 4 IS - 3 SP - 602 EP - 610 PB - Elsevier CY - Amsterdam ER -