State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China; Guelph Research and Development Centre, Agriculture and Agri-Food Canada, 93 Stone Road West, Guelph, Ontario N1G 5C9, Canada; School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, China.
Charlottetown Research & Development Centre, Agriculture and Agri-Food Canada, 440 University Avenue, Charlottetown, Prince Edward Island C1A 4N6, Canada.
Food Chem. 2018 May 30;249:66-76. doi: 10.1016/j.foodchem.2017.12.055. Epub 2017 Dec 14.
A rapid method for producing 9Z- and 13'Z-isomers from all-E-lutein was developed using I-TiO as catalyst. In a simulated in vitro gastrointestinal digestion model, both trans-cis isomerization of all-E-lutein and cis-trans isomerization of Z-luteins occurred during the intestinal phase. The bioaccessibility of all isomers was between 14 and 23%, and it was higher for Z-luteins. In a Caco-2 cell monolayer model, all isomers were relatively stable during cellular uptake and transport across the membrane as no significant isomerization and degradation was detected, but all-E-lutein exhibited significantly higher cellular uptake and transport efficiencies. These results suggest that Z-luteins found in human plasma may likely be formed before intestinal absorption. 13'Z-Lutein also exhibited highest antioxidant activity in FRAP, DPPH and ORAC-L assays, but no significant difference in cell-based antioxidant assay compared with other isomers. Future studies on the different antioxidant activities of cis isomers of lutein in vivo will provide further explanation.
采用 I-TiO 作为催化剂，开发了一种从全反式叶黄素快速制备 9Z-和 13'Z-异构体的方法。在模拟的体外胃肠道消化模型中，在肠道阶段，全反式叶黄素的顺反异构化和 Z-叶黄素的顺反异构化都发生了。所有异构体的生物利用度在 14%至 23%之间，Z-叶黄素的生物利用度更高。在 Caco-2 细胞单层模型中，在细胞摄取和跨膜转运过程中，所有异构体都相对稳定，因为没有检测到明显的异构化和降解，但全反式叶黄素表现出更高的细胞摄取和转运效率。这些结果表明，人血浆中发现的 Z-叶黄素可能是在肠道吸收前形成的。13'Z-叶黄素在 FRAP、DPPH 和 ORAC-L 测定中也表现出最高的抗氧化活性，但与其他异构体相比，在细胞抗氧化测定中没有显著差异。未来在体内研究叶黄素顺式异构体的不同抗氧化活性将提供进一步的解释。
