TY  - JOUR
A1  - Islam, Khan M. S.
A1  - Khalil, Mahmoud Abd Elhamid
A1  - Maenner, Klaus
A1  - Raila, Jens
A1  - Rawel, Harshadrai Manilal
A1  - Zentek, Jürgen
A1  - Schweigert, Florian J.
T1  - Lutein Specific Relationships among Some Spectrophotometric and Colorimetric Parameters of Chicken Egg Yolk
JF  - The journal of poultry science
N2  - Lutein is an essential dietary carotenoid with health benefits and is inter alia responsible for the colouration of egg yolk. The relationship between lutein accumulation and egg yolk colouration was therefore studied in more detail. After feeding a low-luteine diet for 21 days, 14 birds (Lohmann brown hens aged 20 weeks) were fed a diet containing marigold (80 mg lutein/kg feed) and 14 other birds were fed a diet containing oleoresin (45 mg lutein/kg feed) for 21 days; for both groups of birds, this feeding period was followed by withdrawal for 21 days. The Roche Yolk Colour Fan (RYCF) score (0 to 15, where higher values denote greater colour intensity; R-2=0.87; P<0.01) and redness (R-2=0.89; P<0.01) increased with increasing lutein content of egg yolk. Total carotenoid content had a poor relationship with lightness (R-2=0.13; P>0.05) and yellowness (R-2=0.12; P>0.05) of the yolk. It may be concluded that increased lutein is potentially responsible for an increased RYCF score and redness (a*), but decreased yellowness (b*) and lightness (L*), of egg yolk.
KW  - carotenoid
KW  - HPLC
KW  - iCheck
KW  - lutein
KW  - spectrophotometry
KW  - yolk
Y1  - 2017
U6  - https://doi.org/10.2141/jpsa.0160065
SN  - 1346-7395
VL  - 54
SP  - 271
EP  - 277
PB  - Japan Poultry Science Association
CY  - Tsukuba
ER  - 
TY  - JOUR
A1  - Frede, Katja
A1  - Ebert, Franziska
A1  - Kipp, Anna Patricia
A1  - Schwerdtle, Tanja
A1  - Baldermann, Susanne
T1  - Lutein Activates the Transcription Factor Nrf2 in Human Retinal Pigment Epithelial Cells
JF  - Journal of agricultural and food chemistry : a publication of the American Chemical Society
N2  - The degeneration of the retinal pigment epithelium caused by oxidative damage is a stage of development in age related macular degeneration (AMD). The carotenoid lutein is a major macular pigment that may reduce the incidence and progression of AMD, but the underlying mechanism is currently not fully understood. Carotenoids are known to be direct antioxidants. However, carotenoids can also activate cellular pathways resulting in indirect antioxidant effects. Here, we investigate the influence of lutein on the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) target genes in human retinal pigment epithelial cells (ARPE-19 cells) using lutein-loaded Tween40 micelles. The micelles were identified as a suitable delivery system since they were nontoxic in APRE-19 cells up to 0.04% Tween40 and led to a cellular lutein accumulation of 62 mu M +/- 14 mu M after 24 h. Lutein significantly enhanced Nrf2 translocation to the nucleus 1.5 +/- 0.4-fold compared to that of unloaded micelles after 4 h. Furthermore, lutein treatment for 24 h significantly increased the transcripts of NAD(P)H:quinone oxidoreductase 1 (NQO1) by 1.7 +/- 0.1-fold, glutamate-cysteine ligase regulatory subunit (GCLm) by 1.4 +/- 0.1-fold, and heme oxygenase-1 (HO-1) by 1.8 +/- 0.3-fold. Moreover, we observed a significant enhancement of NQO1 activity by 1.2 +/- 0.1-fold. Collectively, this study indicates that lutein not only serves as a direct antioxidant but also activates Nrf 2 in ARPE-19 cells.
KW  - lutein
KW  - Nif2
KW  - ARPE-19 cells
KW  - AMD
KW  - Tween40 micelles
Y1  - 2017
U6  - https://doi.org/10.1021/acs.jafc.7b01929
SN  - 0021-8561
SN  - 1520-5118
VL  - 65
SP  - 5944
EP  - 5952
PB  - American Chemical Society
CY  - Washington
ER  -