title: Effect of dietary α-tocopherol on the bioavailability of lutein in laying hen.
abstract: Lutein and its isomer zeaxanthin have gained considerable interest as possible nutritional ingredient in the prevention of age-related macular degeneration (AMD) in humans. Egg yolk is a rich source of these carotenoids. As an oxidative sensitive component, antioxidants such as α-tocopherol (T) might contribute to an improved accumulation in egg yolk. To test this, chickens were fed lutein esters (LE) with and without α-tocopherol as an antioxidant. After depletion on a wheat-soya bean-based lutein-poor diet for 21 days, laying hens (n = 42) were equally divided into three groups and fed the following diets for 21 days: control (basal diet), a LE group (40 mg LE/kg feed) and LE + T group (40 mg LE plus 100 mg T/kg feed). Eggs and blood were collected periodically. Carotenoids and α-tocopherol in yolk and blood plasma were determined by HPLC. Egg yolk was also analysed for total carotenoids using a one-step spectrophotometric method (iCheck((™)) ). Lutein, zeaxanthin, α-tocopherol and total carotenoids in egg yolk were highest after 14 days of feeding and decreased slightly afterwards. At the end of the trial, eggs of LE + T group contained higher amount of lutein (13.72), zeaxanthin (0.65), α-tocopherol (297.40) and total carotenoids (21.6) compared to the LE group (10.96, 0.55, 205.20 and 18.0 mg/kg, respectively, p < 0.05). Blood plasma values of LE + T group contain higher lutein (1.3), zeaxanthin (0.06) and tocopherol (20.1) compared to LE group (1.02, 0.04 and 14.90 mg/l, respectively, p < 0.05). In conclusion, dietary α-tocopherol enhances bioavailability of lutein reflecting higher content in egg yolk and blood plasma. Improved bioavailability might be due to increased absorption of lutein in the presence of tocopherol and/or a greater stability of lutein/zeaxanthin due to the presence of α-tocopherol as an antioxidant.
authors.affiliation: Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh, Bangladesh. kmsislam1@yahoo.com.|Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany. kmsislam1@yahoo.com.
authors.forename: K M S
authors.initials: KM
authors.lastname: Islam
authors.affiliation: Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Khalil
authors.affiliation: Institute of Animal Nutrition, Freie University, Berlin, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Männer
authors.affiliation: Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Raila
authors.affiliation: Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Rawel
authors.affiliation: Institute of Animal Nutrition, Freie University, Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Zentek
authors.affiliation: Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany.
authors.forename: F J
authors.initials: FJ
authors.lastname: Schweigert
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D001682:Biological Availability; D002645:Chickens / Q000502:physiology*; D004032:Diet / Q000662:veterinary; D004347:Drug Interactions; D004530:Egg Yolk / Q000737:chemistry; D005260:Female; D014975:Lutein / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D010058:Oviposition; D065146:Zeaxanthins / Q000097:blood / Q000378:metabolism; D024502:alpha-Tocopherol / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*
chemical_list: D065146:Zeaxanthins; D024502:alpha-Tocopherol; D014975:Lutein
keywords: HPLC; bioavailability; carotenoids; egg yolk; iCheck; tocopherol