Basic nutritional investigationWheat germ oil: A potential facilitator to improve lutein bioavailability in mice

ObjectiveThe aim of this study is to determine the effect of wheat germ oil (WGO) compared with groundnut oil (GNO) and mixed micelles (control) on lutein bioavailability and bioactivity in mice. The choice of carrier lipid is critical to achieve an enhanced bioavailability of lutein.MethodsMice were intubated with single and repeated doses (2 wk) of lutein solubilized in WGO, GNO, or control mixed micelles to study lutein bioavailability, as well as changes in the lipase activity, antioxidant enzymes, lipid peroxidation, and fatty-acid profile.ResultsSingle-dose (nmol/8 h/mL) and repeated-dose (μg/dL) studies revealed that plasma lutein levels were higher (P > 0.05) in the WGO (88.4 ± 6, 3.2 ± 1) and GNO (23.36 ± 4, 4.7 ± 0.5) groups than in the control (12.4 ± 1, 2.6 ± 0.6) group. Liver and eye lutein levels in WGO (41% and 53%, respectively) and GNO (6% and 41%, respectively) groups also were found to be higher than the control group. However, the dietary lutein response in plasma and tissues was more pronounced in the WGO group than the GNO group. The decrease in plasma malondialdehyde (MDA) levels in the WGO (41%) and GNO (26.4%) groups compared with the control group indicates the higher bioavailability and bioactivity of absorbed lutein.ConclusionThe increased lutein bioavailability in the WGO group compared with the other two groups may be attributed to the polar lipids and intestinal lipase activity found in this study. The results imply a new insight into the application of WGO for improving lutein bioavailability.