Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies
Teas can be classified according to their degree of fermentation, which has been reported to affect both the bioactive components in the teas and their antioxidative activity. In this study, four kinds of commercial Taiwanese tea at different degrees of fermentation, which include green (non-ferment...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2016-10-01
|
| Series: | Molecules |
| Subjects: | |
| Online Access: | http://www.mdpi.com/1420-3049/21/10/1346 |
| _version_ | 1811196705494794240 |
|---|---|
| author | Teeradate Kongpichitchoke Ming-Tzu Chiu Tzou-Chi Huang Jue-Liang Hsu |
| author_facet | Teeradate Kongpichitchoke Ming-Tzu Chiu Tzou-Chi Huang Jue-Liang Hsu |
| author_sort | Teeradate Kongpichitchoke |
| collection | DOAJ |
| description | Teas can be classified according to their degree of fermentation, which has been reported to affect both the bioactive components in the teas and their antioxidative activity. In this study, four kinds of commercial Taiwanese tea at different degrees of fermentation, which include green (non-fermented), oolong (semi-fermented), black (fully fermented), and Pu-erh (post-fermented) tea, were profiled for catechin levels by using high performance liquid chromatography (HPLC). The result indicated that the gallic acid content in tea was directly proportional to the degree of fermentation in which the lowest and highest gallic acid content were 1.67 and 21.98 mg/g from green and Pu-erh tea, respectively. The antioxidative mechanism of the gallic acid was further determined by in vitro and in silico analyses. In vitro assays included the use of phorbol ester-induced macrophage RAW264.7 cell model for determining the inhibition of reactive oxygen species (ROS) production, and PKCδ and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit (p47) activations. The results showed that only at a concentration of 5.00 μM could gallic acid significantly (p < 0.05) reduce ROS levels in phorbol ester-activated macrophages. Moreover, protein immunoblotting expressed similar results in which activations of PKCδ and p47 were only significantly (p < 0.05) attenuated by 5.00 μM treatment. Lastly, in silico experiments further revealed that gallic acid could block PKCδ activation by occupying the phorbol ester binding sites of the protein. |
| first_indexed | 2024-04-12T01:03:29Z |
| format | Article |
| id | doaj.art-5ec63438260944db92d65c518fc54d7d |
| institution | Directory Open Access Journal |
| issn | 1420-3049 |
| language | English |
| last_indexed | 2024-04-12T01:03:29Z |
| publishDate | 2016-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Molecules |
| spelling | doaj.art-5ec63438260944db92d65c518fc54d7d2022-12-22T03:54:21ZengMDPI AGMolecules1420-30492016-10-012110134610.3390/molecules21101346molecules21101346Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico StudiesTeeradate Kongpichitchoke0Ming-Tzu Chiu1Tzou-Chi Huang2Jue-Liang Hsu3Department of Agro-Industry, Assumption University, Bangkok 10240, ThailandTaiwan Tea Experiment Station, Council of Agriculture, Taoyuan 326, TaiwanDepartment of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung 91201, TaiwanDepartment of Biological Science and Technology, National Pingtung University of Science and Technology, Pingtung 91201, TaiwanTeas can be classified according to their degree of fermentation, which has been reported to affect both the bioactive components in the teas and their antioxidative activity. In this study, four kinds of commercial Taiwanese tea at different degrees of fermentation, which include green (non-fermented), oolong (semi-fermented), black (fully fermented), and Pu-erh (post-fermented) tea, were profiled for catechin levels by using high performance liquid chromatography (HPLC). The result indicated that the gallic acid content in tea was directly proportional to the degree of fermentation in which the lowest and highest gallic acid content were 1.67 and 21.98 mg/g from green and Pu-erh tea, respectively. The antioxidative mechanism of the gallic acid was further determined by in vitro and in silico analyses. In vitro assays included the use of phorbol ester-induced macrophage RAW264.7 cell model for determining the inhibition of reactive oxygen species (ROS) production, and PKCδ and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunit (p47) activations. The results showed that only at a concentration of 5.00 μM could gallic acid significantly (p < 0.05) reduce ROS levels in phorbol ester-activated macrophages. Moreover, protein immunoblotting expressed similar results in which activations of PKCδ and p47 were only significantly (p < 0.05) attenuated by 5.00 μM treatment. Lastly, in silico experiments further revealed that gallic acid could block PKCδ activation by occupying the phorbol ester binding sites of the protein.http://www.mdpi.com/1420-3049/21/10/1346Taiwanese teadegree of fermentationcatechinsgallic acidantioxidative activityRAW264.7protein kinase Cmolecular docking |
| spellingShingle | Teeradate Kongpichitchoke Ming-Tzu Chiu Tzou-Chi Huang Jue-Liang Hsu Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies Molecules Taiwanese tea degree of fermentation catechins gallic acid antioxidative activity RAW264.7 protein kinase C molecular docking |
| title | Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies |
| title_full | Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies |
| title_fullStr | Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies |
| title_full_unstemmed | Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies |
| title_short | Gallic Acid Content in Taiwanese Teas at Different Degrees of Fermentation and Its Antioxidant Activity by Inhibiting PKCδ Activation: In Vitro and in Silico Studies |
| title_sort | gallic acid content in taiwanese teas at different degrees of fermentation and its antioxidant activity by inhibiting pkcδ activation in vitro and in silico studies |
| topic | Taiwanese tea degree of fermentation catechins gallic acid antioxidative activity RAW264.7 protein kinase C molecular docking |
| url | http://www.mdpi.com/1420-3049/21/10/1346 |
| work_keys_str_mv | AT teeradatekongpichitchoke gallicacidcontentintaiwaneseteasatdifferentdegreesoffermentationanditsantioxidantactivitybyinhibitingpkcdactivationinvitroandinsilicostudies AT mingtzuchiu gallicacidcontentintaiwaneseteasatdifferentdegreesoffermentationanditsantioxidantactivitybyinhibitingpkcdactivationinvitroandinsilicostudies AT tzouchihuang gallicacidcontentintaiwaneseteasatdifferentdegreesoffermentationanditsantioxidantactivitybyinhibitingpkcdactivationinvitroandinsilicostudies AT juelianghsu gallicacidcontentintaiwaneseteasatdifferentdegreesoffermentationanditsantioxidantactivitybyinhibitingpkcdactivationinvitroandinsilicostudies |