PDF
Full
Outline
Theaflavins (TF) are water-soluble pigments in tea. They possess rich biological activities such as antioxidant, antibacterial, alleviating metabolic syndrome, anti-inflammatory, tooth-protecting, neuroprotective, and antidepressant effects, and thus have broad application prospects. Given the complex structure, unstable chemical properties, low extraction efficiency, and the difficulty in obtaining TF, the oxidative preparation of TF has attracted significant attention. Oxidation preparation methods of TF include the chemical method and the enzymatic method. Chemical method utilizes a chemical oxidant. It features a uniform oxidation degree and strong controllability, and generates more ester TF in an acidic environment. However, the chemical oxidation method has poor specificity. Consequently, it is necessary to protect the hydroxyl group on the catechin A-ring to enhance the yield of TF. Moreover, the amount of oxidant required is large, and safety is a concern. In enzymatic preparation, polyphenol oxidase and peroxidase are employed. The conditions are mild, efficient, and specific. Efficiency of enzymatically preparing TF is influenced by the sources and types of oxidases, substrate composition, and reaction parameters. Yield of TF can be increased by preferentially oxidizing the oxidases of catechol catechins, increasing the proportion of biphenyl catechins, and reacting for an extended period in a weak-acid and low-temperature environment. Nevertheless, the current preparation methods still face problems such as a low extraction rate and low product purity. This paper discussed 2 kinds of oxidation preparation methods, and summarized their biological activities, in order to provide reference for the industrial production and application research of TF.
PDF
378
183
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |
关闭全屏
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
