Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process
Catechins belonging to polyhydroxylated polyphenols are the primary compounds found in green tea. They are associated with many physiological properties. Epicatechin (EC) is a non-gallate-type catechin with four phenolic hydroxyl groups attached. The changes in EC treated with color light illuminati...
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| Format: | Article |
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MDPI AG
2019-02-01
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| Series: | Molecules |
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| Online Access: | https://www.mdpi.com/1420-3049/24/4/787 |
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| author | Shiuh-Tsuen Huang Yi-An Hung Meei-Ju Yang Iou-Zen Chen Jeu-Ming P. Yuann Ji-Yuan Liang |
| author_facet | Shiuh-Tsuen Huang Yi-An Hung Meei-Ju Yang Iou-Zen Chen Jeu-Ming P. Yuann Ji-Yuan Liang |
| author_sort | Shiuh-Tsuen Huang |
| collection | DOAJ |
| description | Catechins belonging to polyhydroxylated polyphenols are the primary compounds found in green tea. They are associated with many physiological properties. Epicatechin (EC) is a non-gallate-type catechin with four phenolic hydroxyl groups attached. The changes in EC treated with color light illumination in an alkaline condition were investigated by chromatographic and mass analyses in this study. In particular, the superoxide anion radical (O<sub>2</sub>•<sup>−</sup>) was investigated during the EC photolytic process. EC is unstable under blue light illumination in an alkaline solution. When EC was treated with blue light illumination in an alkaline solution, O<sub>2</sub>•<sup>−</sup> was found to occur via a photosensitive redox reaction. In addition, the generation of monomeric, dimeric, and trimeric compounds is investigated. On the other hand, epigallocatechin gallate (EGCG), which is a gallate-type catechin, is stable under blue light illumination in an alkaline solution. Adding EGCG, during the blue light illumination treatment of EC decreased photolytic formation, suggesting that gallate-type catechins can suppress the photosensitive oxidation of EC. Gallate-type catechins are formed via the esterification of non-gallate-type catechins and gallic acid (GA). The carbonyl group on the gallate moiety of gallate-type catechins appears to exhibit its effect on the stability against the photosensitive oxidation caused by blue light illumination. |
| first_indexed | 2024-04-14T06:40:22Z |
| format | Article |
| id | doaj.art-87e5ffacc4eb4d6182db07788fcde367 |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-04-14T06:40:22Z |
| publishDate | 2019-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-87e5ffacc4eb4d6182db07788fcde3672022-12-22T02:07:21ZengMDPI AGMolecules1420-30492019-02-0124478710.3390/molecules24040787molecules24040787Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic ProcessShiuh-Tsuen Huang0Yi-An Hung1Meei-Ju Yang2Iou-Zen Chen3Jeu-Ming P. Yuann4Ji-Yuan Liang5Department of Science Education and Application, National Taichung University of Education, Taichung 40306, TaiwanDepartment of Biotechnology, Ming-Chuan University, Gui-Shan 33343, TaiwanTea Research and Extension Station, Taoyuan 32654, TaiwanDepartment of Horticulture and Landscape Architecture, National Taiwan University, Taipei 10617, TaiwanDepartment of Biotechnology, Ming-Chuan University, Gui-Shan 33343, TaiwanDepartment of Biotechnology, Ming-Chuan University, Gui-Shan 33343, TaiwanCatechins belonging to polyhydroxylated polyphenols are the primary compounds found in green tea. They are associated with many physiological properties. Epicatechin (EC) is a non-gallate-type catechin with four phenolic hydroxyl groups attached. The changes in EC treated with color light illumination in an alkaline condition were investigated by chromatographic and mass analyses in this study. In particular, the superoxide anion radical (O<sub>2</sub>•<sup>−</sup>) was investigated during the EC photolytic process. EC is unstable under blue light illumination in an alkaline solution. When EC was treated with blue light illumination in an alkaline solution, O<sub>2</sub>•<sup>−</sup> was found to occur via a photosensitive redox reaction. In addition, the generation of monomeric, dimeric, and trimeric compounds is investigated. On the other hand, epigallocatechin gallate (EGCG), which is a gallate-type catechin, is stable under blue light illumination in an alkaline solution. Adding EGCG, during the blue light illumination treatment of EC decreased photolytic formation, suggesting that gallate-type catechins can suppress the photosensitive oxidation of EC. Gallate-type catechins are formed via the esterification of non-gallate-type catechins and gallic acid (GA). The carbonyl group on the gallate moiety of gallate-type catechins appears to exhibit its effect on the stability against the photosensitive oxidation caused by blue light illumination.https://www.mdpi.com/1420-3049/24/4/787blue lightcatechinepicatechinEGCGgallic acid |
| spellingShingle | Shiuh-Tsuen Huang Yi-An Hung Meei-Ju Yang Iou-Zen Chen Jeu-Ming P. Yuann Ji-Yuan Liang Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process Molecules blue light catechin epicatechin EGCG gallic acid |
| title | Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process |
| title_full | Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process |
| title_fullStr | Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process |
| title_full_unstemmed | Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process |
| title_short | Effects of Epigallocatechin Gallate on the Stability of Epicatechin in a Photolytic Process |
| title_sort | effects of epigallocatechin gallate on the stability of epicatechin in a photolytic process |
| topic | blue light catechin epicatechin EGCG gallic acid |
| url | https://www.mdpi.com/1420-3049/24/4/787 |
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