Oxidative Transformation of Tea Catechins

2001 ◽  
pp. 102-112
Author(s):  
Chi-Tang Ho ◽  
Nanqun Zhu ◽  
Tzou-Chi Huang
Keyword(s):  
Oxidative Transformation ◽  
Tea Catechins

THE INFLUENCE OF HAEMOGLOBIN-S AND G6PD DEFICIENCY ON THE ACTIVITY OF THE 17β-HYDROXYSTEROID DEHYDROGENASE OF INTACT HUMAN ERYTHROCYTES

1974 ◽  
Vol 75 (4) ◽  
pp. 793-800
Author(s):  
A. O. Sogbesan ◽  
O. A. Dada ◽  
B. Kwaku Adadevoh
Keyword(s):  
Enzyme Activity ◽  
Dehydrogenase Activity ◽  
Sex Steroids ◽  
G6pd Deficiency ◽  
Incubation Medium ◽  
Hydroxysteroid Dehydrogenase ◽  
G6pd Activity ◽  
Reverse Transformation ◽  
Oxidative Transformation ◽  
Haemoglobin S

ABSTRACT The 17β-hydroxysteroid dehydrogenase activity in intact erythrocytes of Nigerian patients, in particular with regard to haemoglobin genotypes and G6PD* activity was studied. The G6PD activity of the erythrocyte did not affect the oxidative transformation of testosterone to androstenedione and of oestradiol to oestrone. The reduction (reverse transformation) was inhibited in G6PD-deficient erythrocytes but this inhibition was offset by the addition of 0.025 m glucose to the incubation medium. The per cent oxidation transformation of testosterone was higher in Hb-AA than in Hb-SS erythrocytes. It is suggested that the differences may be a result of either lower enzyme activity in the Hb-SS erythrocytes or of differences in the uptake and possibly binding of sex steroids by intact Hb-SS and Hb-AA erythrocytes.

Green tea catechins attenuate high-fat diet effects related to obesity and diabetes without effect hypothalamic expression of TLR4 pathway or serotoninergic 1B and 2C receptors

2013 ◽  
Author(s):  
Marcos Hiromu Okuda ◽  
de Santana Aline Alves ◽  
Mayara Franzoi Moreno ◽  
Ana Claudia Hachul ◽  
Nelson Inacio Neto ◽  
...  
Keyword(s):  
Green Tea ◽  
High Fat Diet ◽  
High Fat ◽  
Tea Catechins ◽  
Green Tea Catechins ◽  
Obesity And Diabetes

The Protective Effects of Green Tea Catechins in the Management of Neurodegenerative Diseases: A Review

2019 ◽  
Vol 16 (1) ◽  
pp. 57-65 ◽  
Author(s):  
Tahereh Farkhondeh ◽  
Hanieh Shaterzadeh Yazdi ◽  
Saeed Samarghandian
Keyword(s):  
Neurodegenerative Diseases ◽  
Signaling Pathways ◽  
Green Tea ◽  
Molecular Mechanisms ◽  
Main Role ◽  
Related Factor ◽  
Protective Effects ◽  
Tea Catechins ◽  
Green Tea Catechins ◽  
And Control

Background: The therapeutic strategies to manage neurodegenerative diseases remain limited and it is necessary to discover new agents for their prevention and control. Oxidative stress and inflammation play a main role in the pathogenesis of neurodegenerative diseases. The aim of this study is to review the effects of green tea catechins against the Neurodegenerative Diseases. Methods: In this study, we extensively reviewed all articles on the terms of Green tea, catechins, CNS disorders, and different diseases in PubMed, Science Direct, Scopus, and Google Scholar databases between the years 1990 and 2017. Results: The present study found that catechins, the major flavonoids in green tea, are powerful antioxidants and radical scavengers which possess the potential roles in the management of neurodegenerative diseases. Catechins modulate the cellular and molecular mechanisms through the inflammation-related NF-&amp;#954;B and the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathways. Conclusion: The findings of the present review shows catechins could be effective against neurodegenerative diseases due to their antioxidation and anti-inflammation effects and the involved biochemical pathways including Nrf2 and NF-kB signaling pathways.<P&gt;

Sterically Crowded Heterocycles. X. A New Mechanistic Approach to the Ferricyanide Oxidation of 4,6'-Disubstituted 1-(Pyridin-2'-yl)-2,6-diphenylpyridinium Salts

1999 ◽  
Vol 64 (8) ◽  
pp. 1274-1294 ◽  
Author(s):  
Radek Pohl ◽  
Stanislav Böhm ◽  
Josef Kuthan
Keyword(s):  
Transition States ◽  
Oxidative Transformation ◽  
Steric Interactions ◽  
Radical Intermediates ◽  
Mechanistic Approach

The oxidations of the title perchlorates, bearing the sterically diverse 6'-substituents (H, Me, Et, i-Pr, n-Bu, t-Bu and Ph) in two series with the same 4-substituents (Ph and t-Bu) lead to pairs of isomeric 3',5-disubstituted (Z)-1'-phenyl-3'-(2-phenylimidazo[1,2-a]pyridin-3-yl)prop-2'- en-1'-ones and 3,6'-disubstituted [5-phenyl-1-(6'-pyridin-2'-yl)-1H-pyrrol-2-yl](phenyl)methanones except where the both variable substituents are t-Bu and then only pyrrolic product is formed. Considering steric interactions of the substituents in some intermediate and/or transition states a multistep mechanism for the oxidative transformation is proposed and supported by model PM3-PECI calculations of some radical intermediates.

Oxidative transformation of alcohols and organic halides in aqueous solution

2014 ◽  
Vol 38 (8) ◽  
pp. 3749-3754 ◽  
Author(s):  
Neeraj Gupta ◽  
Apoorva Thakur ◽  
Pushpa Bhardwaj
Keyword(s):  
Aqueous Solution ◽  
Oxidative Transformation ◽  
Organic Halides ◽  
Oxidation Of Alcohols

Using water as the only solvent for the oxidation of alcohols and organic halides, a complete solventless process for the preparation of water immiscible aldehydes has been developed.

Neuroprotection of green tea catechins on surgical menopause-induced overactive bladder in a rat model

2012 ◽  
Vol 19 (3) ◽  
pp. 346-354 ◽  
Author(s):  
Yung-Shun Juan ◽  
Shu-Mien Chuang ◽  
Cheng-Yu Long ◽  
Chung-Hwan Chen ◽  
Robert M. Levin ◽  
...  
Keyword(s):  
Overactive Bladder ◽  
Green Tea ◽  
Rat Model ◽  
Tea Catechins ◽  
Green Tea Catechins ◽  
Surgical Menopause

scholarly journals Anti-Influenza with Green Tea Catechins: A Systematic Review and Meta-Analysis

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4014
Author(s):  
Anchalee Rawangkan ◽  
Kirati Kengkla ◽  
Sukrit Kanchanasurakit ◽  
Acharaporn Duangjai ◽  
Surasak Saokaew
Keyword(s):  
Systematic Review ◽  
Green Tea ◽  
Viral Infections ◽  
Influenza Infection ◽  
Meta Analysis ◽  
Influenza Virus Infection ◽  
Control Group ◽  
Tea Consumption ◽  
Tea Catechins ◽  
Green Tea Catechins

Influenza is one of the most serious respiratory viral infections worldwide. Although several studies have reported that green tea catechins (GTCs) might prevent influenza virus infection, this remains controversial. We performed a systematic review and meta-analysis of eight studies with 5,048 participants that examined the effect of GTC administration on influenza prevention. In a random-effects meta-analysis of five RCTs, 884 participants treated with GTCs showed statistically significant effects on the prevention of influenza infection compared to the control group (risk ratio (RR) 0.67, 95%CIs 0.51–0.89, P = 0.005) without evidence of heterogeneity (I2= 0%, P = 0.629). Similarly, in three cohort studies with 2,223 participants treated with GTCs, there were also statistically significant effects (RR 0.52, 95%CIs 0.35–0.77, P = 0.001) with very low evidence of heterogeneity (I2 = 3%, P = 0.358). Additionally, the overall effect in the subgroup analysis of gargling and orally ingested items (taking capsules and drinking) showed a pooled RR of 0.62 (95% CIs 0.49–0.77, P = 0.003) without heterogeneity (I2= 0%, P = 0.554). There were no obvious publication biases (Egger’s test (P = 0.138) and Begg’s test (P = 0.103)). Our analysis suggests that green tea consumption is effective in the prophylaxis of influenza infections. To confirm the findings before implementation, longitudinal clinical trials with specific doses of green tea consumption are warranted.

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