Antioxidant Activity of Various Tea Extracts in Relation to Their Antimutagenicity

Yen, Gow‐Chin; Chen, Hui-Yin

doi:10.1021/jf00049a007

Cited by 2,152 publications

(1,188 citation statements)

References 29 publications

Supporting

Mentioning

1,118

Contrasting

Unclassified

Order By: Relevance

“…A method described by Yen and Chen was used to determine the activity against DPPH • [30]. The 0.1 mL samples were combined with 2 mL of DPPH • solution (1 mM) and incubated at ambient temperature for 30 min.…”

Section: Chemical Analysis Of the Samplesmentioning

confidence: 99%

The Application of Supercritical Carbon Dioxide and Ethanol for the Extraction of Phenolic Compounds from Chokeberry Pomace

et al. 2017

View full text Add to dashboard Cite

Chokeberry (Aronia melanocarpa (Michx.) Elliot) is a fruit with exceptionally high levels of phenolic compounds which are accumulated mainly in the peel; hence, the majority remains in the leftovers after juice production. Extraction with the use of carbon dioxide in supercritical conditions was used to isolate phenolic compounds from the pomace. The effect of the process parameters (temperature; pressure; and the addition of ethanol) on the extraction yields and properties of the extracts was investigated. The anthocyanin and total phenolic compound content, as well as the scavenging activity against five selected radicals, were evaluated. The best results were acquired for 35 • C, 10 MPa, and 80% m/m ethanol addition, the yield of phenolic compounds was 1.52 g per 100 g of pomace. The amount of extracted phenolics and the antioxidative attributes of the extracts were highly correlated. The impact of supercritical carbon dioxide density on the amount of recovered compounds was confirmed. The use of supercritical CO 2 led to a significant reduction in the volume of organic solvent required for extraction.

show abstract

Section: Chemical Analysis Of the Samplesmentioning

confidence: 99%

The Application of Supercritical Carbon Dioxide and Ethanol for the Extraction of Phenolic Compounds from Chokeberry Pomace

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Tea¯avonoids (such as catechins, thea¯avins and thearubigins) seem to be powerful antioxidants, which may explain this protective effect of tea against cardiovascular disease. In vitro studies have demonstrated that green and black tea infusions indeed possess considerable antioxidant activity (Yen & Chen, 1995;Robinson et al, 1997;Gardner et al, 1998). Tea polyphenols may prevent development of atherosclerosis by protecting low density lipoproteins (LDL) against oxidation (Diaz et al, 1997) as shown in vitro (Luo et al, 1997;Van het Hof et al, 1997).…”

Section: Introductionmentioning

confidence: 99%

A single dose of tea with or without milk increases plasma antioxidant activity in humans

et al. 2000

View full text Add to dashboard Cite

Objective: To investigate the effect of black and green tea consumption, with and without milk, on the plasma antioxidant activity in humans. Design: In a complete cross-over design, 21 healthy volunteers (10 male, 11 female) received a single dose of black tea, green tea (2 g tea solids in 300 ml water) or water with or without milk. Blood samples were obtained at baseline and at several time points up to 2 h post-tea drinking. Plasma was analysed for total catechins and antioxidant activity, using the ferric reducing ability of plasma (FRAP) assay. Results: Consumption of black tea resulted in a signi®cant increase in plasma antioxidant activity reaching maximal levels at about 60 min. A larger increase was observed after consumption of green tea. As anticipated from the higher catechin concentration in green tea, the rise in plasma total catechins was signi®cantly higher after consumption of green tea when compared to black tea. Addition of milk to black or green tea did not affect the observed increases in plasma antioxidant activity. Conclusions: Consumption of a single dose of black or green tea induces a signi®cant rise in plasma antioxidant activity in vivo. Addition of milk to tea does not abolish this increase. Whether the observed increases in plasma antioxidant activity after a single dose of tea prevent in vivo oxidative damage remains to be established.

show abstract

“…In general, phenolics and specifically caffeic acid derivatives have high antioxidant and antimutagenic activities Tsai et al, 2012). TCEPARs have been reported to possess higher concentrations of phenolics and flavonoids (Jeong et al, 2009;Wu et al, 2008) Some studies support the view that compounds with antioxidant activity can inhibit mutations because they scavenge free radicals or induce antioxidant enzyme activity (Yen and Chen, 1995).…”

Section: Discussionmentioning

confidence: 99%

Biosafety and Toxicological Evaluation of Tissue-Cultured Echinacea purpurea Adventitious Roots

Murthy¹,

Park²,

Lee³

et al. 2015

HST

View full text Add to dashboard Cite

Echinacea purpurea (L.) Moench (purple cone flower) is an important medicinal plant; it can enhance immunity, relieve pain, and reduce inflammation, and also has hormonal, antiviral, and antioxidant effects. Adventitious root biomass of Echinacea purpurea was produced in commercial-scale bioreactors for use as a dietary supplement in the food industry and in traditional medicine. Biosafety and toxicological evaluations of tissue-cultured Echinacea purpurea adventitious roots (TCEPARs) were performed. Reverse mutation and chromosomal aberration tests showed no significant mutagenicity. Furthermore, repeated four-week oral dose tests performed in Sprague-Dawley rats did not show any notable changes in the general behavior of the rats, in the gross appearance of their internal organs, or in their mortality rate. There were no differences between the control group and the treatment group in parameters such as absolute body weight, hematology, blood chemistry, and absolute and relative organ weights. These findings indicate that TCEPARs are safe and nontoxic when consumed at an average dietary level and can be used as raw material for traditional medicine and the food industry.

show abstract

Antioxidant Activity of Various Tea Extracts in Relation to Their Antimutagenicity

Cited by 2,152 publications

References 29 publications

The Application of Supercritical Carbon Dioxide and Ethanol for the Extraction of Phenolic Compounds from Chokeberry Pomace

The Application of Supercritical Carbon Dioxide and Ethanol for the Extraction of Phenolic Compounds from Chokeberry Pomace

A single dose of tea with or without milk increases plasma antioxidant activity in humans

Biosafety and Toxicological Evaluation of Tissue-Cultured Echinacea purpurea Adventitious Roots

Contact Info

Product

Resources

About