Z-Isomers of Astaxanthin Exhibit Greater Bioavailability and Tissue Accumulation Efficiency than the All-E-Isomer

Abstract

The purpose of the present study was to clarify the differences in the bioavailability and tissue accumulation efficiency between (all-E)-and (Z)-astaxanthin. Astaxanthin with a high proportion of the Z-isomer (especially rich in the 9Z-and 13Zisomers) was prepared from (all-E)-astaxanthin by thermal treatment and solid−liquid separation. The all-E-isomer-or Z-isomer-rich diet was fed to male rats for 2 weeks. After the feeding period, blood and tissue samples were collected, and their astaxanthin levels were evaluated. The Z-isomer-rich astaxanthin diet resulted in higher levels of astaxanthin in blood and many tissues (in particular, skin, lung, prostate, and eye) compared to the all-E-isomer-rich diet. Moreover, the Z-isomer-rich diet enhanced the level of the 13Zisomer in blood and tissues rather than that of the 9Z-isomer. These results strongly supported that astaxanthin Z-isomers have greater bioavailability and tissue accumulation efficiency than the all-E-isomer. Moreover, (13Z)-astaxanthin would have higher bioavailability and tissue accumulation than the other isomers.

Application of <i>E/Z</i>-Isomerization Technology for Enhancing Processing Efficiency, Health-Promoting Effects, and Usability of Carotenoids: A Review and Future Perspectives

“…Therefore, it is important to understand the differences properly and accordingly develop products that can exploit the characteristics of each isomer. Several studies have demonstrated that various carotenoid Z-isomers, such as lycopene, lutein, and astaxanthin, possess greater bioavailability than the all-E-isomers 16,18,19,20) . Moreover, our group recently elucidated that Z-isomers of carotenoids (lycopene, β-carotene, lutein, and astaxanthin) exhibit excellent tissue accumulation efficiency (Table 1) 19,20) .…”

“…Several studies have demonstrated that various carotenoid Z-isomers, such as lycopene, lutein, and astaxanthin, possess greater bioavailability than the all-E-isomers 16,18,19,20) . Moreover, our group recently elucidated that Z-isomers of carotenoids (lycopene, β-carotene, lutein, and astaxanthin) exhibit excellent tissue accumulation efficiency (Table 1) 19,20) . For example, an oral administration trial in rats fed with all-E-isomer-rich lycopene diet (total Z-isomer ratio＝0.5％) or the Z-isomer-rich lycopene diet (total Z-isomer ratio＝80.8％) showed that the latter diet induced 11.6-, 4.6-, 5.8-, 14.0-, 3.0-, and 2.5-fold increases in lycopene concentrations in the liver, lung, kidney, adrenal, testis, and skin, respectively, compared to the former diet 19) .…”

“…Numerous studies have demonstrated that several bio-Table 1 Effects of oral administration of all-E-or Z-isomer-carotenoids (lycopene, β-carotene, lutein, and astaxanthin) on the plasma and tissue concentrations in rats after 2-week feeding of the test diets 19,20) . logical activities, such as antioxidant, anti-inflammatory, antiaging, and anticancer activities, vary significantly among carotenoid isomers 14, 22−24, 26, 71−75) .…”

DFT-based Raman spectral study of astaxanthin geometrical isomers

“…AST is known as a super antioxidant, which can effectively remove free radicals from the body, and promote a variety of physiological functions, such as suppressing oxidation, lowering lipid and enhancing immunity activities ( Liu and Huang, 2016 , Visioli and Artaria, 2017 ). Therefore, it has recently attracted a lot of attention in both scientific research and applied areas ( Ambati et al, 2014 , de Bruijn et al, 2016 , Honda et al, 2021a , Honda et al, 2021b , Liu et al, 2016 , Visioli and Artaria, 2017 , Yang et al, 2021 , Yu and Liu, 2020 ). Currently, AST products have been commercially used in safe food additives, nutritional products, cosmetics, aquaculture ( Ambati et al, 2014 , Yang et al, 2021 ).…”

“…For example, during in vitro digestion, the 13- cis shows higher bioavailability than 9- cis and all- trans ASTs, and 9- cis shows higher transport efficiency than all- trans and 13- cis ( Visioli and Artaria, 2017 , Yang et al, 2017 ). Based on AST fed to male rats, it was supported that the cis -AST isomers, the 13- cis have greater bioavailability and tissue accumulation efficiency than the all- trans -isomer ( Honda et al, 2021b ). The cis isomers of AST show much higher antioxidant efficacy than all- trans isomer in vitro ( Liu and Osawa, 2007 ).…”