Separation of epigallocatechin gallate and epicatechin gallate from tea polyphenols by macroporous resin and crystallization

2021 ◽  
Author(s):  
Li Wang ◽  
Xin Huang ◽  
Huijuan Jing ◽  
Xin Ye ◽  
Chao Jiang ◽  
...  
Keyword(s):  
Green Tea ◽  
Epigallocatechin Gallate ◽  
Tea Polyphenols ◽  
Green Tea Polyphenols ◽  
Macroporous Resin ◽  
Epicatechin Gallate

Epigallocatechin gallate (EGCG) and epicatechin gallate (ECG) are the most abundant ester catechins of green tea polyphenols (GTPs) with numerous potential bioactivities, which have a wide application prospect in the...

scholarly journals Prospective randomized trial evaluating blood and prostate tissue concentrations of green tea polyphenols and quercetin in men with prostate cancer

2020 ◽  
Vol 11 (5) ◽  
pp. 4114-4122
Author(s):  
Susanne M. Henning ◽  
Piwen Wang ◽  
Ru-Po Lee ◽  
Amy Trang ◽  
George Husari ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Randomized Trial ◽  
Green Tea ◽  
Epigallocatechin Gallate ◽  
Potential Effect ◽  
Tea Polyphenols ◽  
Green Tea Polyphenols ◽  
Prostate Tissue ◽  
Epicatechin Gallate ◽  
Tissue Concentrations

Epigallocatechin gallate, epicatechin gallate (Green Tea Polyphenols – GTPs) and quercetin (Q) were taken up in prostate tissue after Q and GTP consumption. Our findings herein suggest a potential effect of Q on GTP metabolism.

scholarly journals Epigallocatechin Gallate (EGCG), a Green Tea Polyphenol, Reduces Coronavirus Replication in a Mouse Model

Viruses ◽  
2021 ◽  
Vol 13 (12) ◽  
pp. 2533
Author(s):  
Rackhyun Park ◽  
Minsu Jang ◽  
Yea-In Park ◽  
Yeonjeong Park ◽  
Woochul Jung ◽  
...  
Keyword(s):  
Mouse Model ◽  
Green Tea ◽  
Particle Production ◽  
Epigallocatechin Gallate ◽  
Tea Polyphenols ◽  
Green Tea Polyphenols ◽  
Tea Polyphenol ◽  
Green Tea Polyphenol

The COVID-19 pandemic has resulted in a huge number of deaths from 2020 to 2021; however, effective antiviral drugs against SARS-CoV-2 are currently under development. Recent studies have demonstrated that green tea polyphenols, particularly EGCG, inhibit coronavirus enzymes as well as coronavirus replication in vitro. Herein, we examined the inhibitory effect of green tea polyphenols on coronavirus replication in a mouse model. We used epigallocatechin gallate (EGCG) and green tea polyphenols containing more than 60% catechin (GTP60) and human coronavirus OC43 (HCoV-OC43) as a surrogate for SARS-CoV-2. Scanning electron microscopy analysis results showed that HCoV-OC43 infection resulted in virion particle production in infected cells. EGCG and GTP60 treatment reduced coronavirus protein and virus production in the cells. Finally, EGCG- and GTP60-fed mice exhibited reduced levels of coronavirus RNA in mouse lungs. These results demonstrate that green tea polyphenol treatment is effective in decreasing the level of coronavirus in vivo.

Effects of phenolic compounds on the heat stability of milk and concentrated milk

1999 ◽  
Vol 66 (3) ◽  
pp. 399-407 ◽  
Author(s):  
JOHN E. O'CONNELL ◽  
PATRICK F. FOX
Keyword(s):  
Phenolic Compounds ◽  
Green Tea ◽  
Skim Milk ◽  
Epigallocatechin Gallate ◽  
Quinic Acid ◽  
Heat Stability ◽  
Green Tea Polyphenols ◽  
Epicatechin Gallate ◽  
Ph Profile ◽  
Concentrated Milk

A methanol extract of green tea was fractionated on Sephadex LH-20. The compounds eluted were identified by thin layer chromatography as catechin–epicatechin, gallocatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate. When added to milk at 2·0 g/l, these polyphenols, apart from the catechin–epicatechin mixture, increased the heat stability of skim milk, particularly in the region of the minimum (pH 6·8–7·1). When added at 0·4 g/l, green tea polyphenols also increased the heat stability of concentrated milk. The effects of other phenolic compounds on the heat stability of milk were also examined. Chlorogenic acid, guaiacol, thymol, vanillin, butylene hydroxyanisole, propyl gallate and butylene hydroxytoluene did not affect the heat stability of milk or concentrated milk. Quinic acid markedly reduced the heat stability of skim milk. Pyrogallol, catechol, tannic acid, ellagic acid, phloroglucinol and gallate converted a type A heat coagulation time–pH profile to a type B profile. Ferulic acid and vanillic acid increased heat stability in the region of the maximum, with little effect on the minimum, and stability did not recover at pH values on the alkaline side of the minimum. Caffeic acid increased the heat stability of milk while the related non-phenolic compounds 2,5-dimethoxycinnamic acid and 3,4-dimethoxycinnamic acid had no effect.

scholarly journals Green Tea Polyphenols Function as Prooxidants To Activate Oxidative-Stress-Responsive Transcription Factors in Yeasts

2006 ◽  
Vol 73 (2) ◽  
pp. 572-580 ◽  
Author(s):  
Kazuhiro Maeta ◽  
Wataru Nomura ◽  
Yoshifumi Takatsume ◽  
Shingo Izawa ◽  
Yoshiharu Inoue
Keyword(s):  
Oxidative Stress ◽  
Transcription Factors ◽  
Green Tea ◽  
Nuclear Localization ◽  
Disulfide Bonds ◽  
Epigallocatechin Gallate ◽  
Tea Polyphenols ◽  
Green Tea Polyphenols ◽  
Alkaline Conditions ◽  
Tea Extract

ABSTRACT Epigallocatechin gallate (EGCG) is the most abundant polyphenolic flavonoid in green tea. Catechin and its derivatives, including EGCG, are widely believed to function as antioxidants. Here we demonstrate that both EGCG and green tea extract (GTE) cause oxidative stress-related responses in the budding yeast Saccharomyces cerevisiae and the fission yeast Schizosaccharomyces pombe under weak alkaline conditions in terms of the activation of oxidative-stress-responsive transcription factors. GTE as well as EGCG induced the nuclear localization of Yap1 in S. cerevisiae, which was repressed by the addition of catalase but not by the addition of superoxide dismutase. The same phenomena were observed for the nucleocytoplasmic localization of Msn2 in S. cerevisiae and Pap1, a Yap1 homologue, in S. pombe. The formation of intramolecular disulfide bonds has been proposed to be crucial for the H2O2-induced nuclear localization of Yap1, and we verified the importance of cysteine residues of Yap1 in response to EGCG and GTE. Additionally, we show that EGCG and GTE produce H2O2 in a weak alkaline medium. Finally, we conclude that tea polyphenols are able to act as prooxidants to cause a response to oxidative stress in yeasts under certain conditions.

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