Rapid and Efficient Conversion of All-E-astaxanthin to 9Z- and 13Z-Isomers and Assessment of Their Stability and Antioxidant Activities
| Autor: | Cheng Yang, Leiyan Wu, Qingrui Sun, Ronghua Liu, Jing Li, Lianfu Zhang, Rong Tsao, Hua Zhang |
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| Rok vydání: | 2017 |
| Předmět: |
Chromatography
Antioxidant Molecular Structure DPPH medicine.medical_treatment Radical Ethyl acetate 04 agricultural and veterinary sciences General Chemistry Xanthophylls 040401 food science High-performance liquid chromatography Antioxidants Bioavailability chemistry.chemical_compound 0404 agricultural biotechnology Isomerism chemistry In vivo medicine General Agricultural and Biological Sciences Oxidation-Reduction Isomerization |
| Zdroj: | Journal of Agricultural and Food Chemistry. 65:818-826 |
| ISSN: | 1520-5118 0021-8561 |
| DOI: | 10.1021/acs.jafc.6b04962 |
| Popis: | An optimized isomerization method was developed by heating all-E-astaxanthin in ethyl acetate (70 °C) with I-TiO2 catalyst, yielding 22.7% and 16.9% of 9Z- and 13Z-astaxanthin, respectively, in 2 h, with 92–95% purity after semipreparative HPLC purification. 13Z-Astaxanthin had higher antioxidant activity than all-E- and 9Z-astaxanthins in oxygen radical absorbing capacity assay for lipophilic compounds, photochemiluminescence, and cellular antioxidant activity (CAA) assays, and 9Z-astaxanthin was higher in DPPH radical-scavenging activity assay and lower in CAA assay. All isomers were relatively stable between pH 2.0 and 11.6, except 13Z- and 9Z-astaxanthins at pH 2.0, suggesting they may be converted after passing the gastric phase in vivo. Metal ions did not significantly (p < 0.05) affect the stability. Results of the current study provides a means for further study into the mechanisms related to in vivo transformation and bioavailability of Z-astaxanthins, and their application in the development of ... |
| Databáze: | OpenAIRE |
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