New dibenzotropolone derivatives characterized from black tea using LC/MS/MS

Sang, Shengmin; Tian, Shiying; Yang, Chung S.; Ho, Chi‐Tang

doi:10.1016/j.bmc.2004.03.027

Cited by 47 publications

(35 citation statements)

References 25 publications

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“…Additionally, TFs can be further condensed into dimers or oligomers, which should have more deep color than simple TFs (Tanaka, Betsumiya, Mine, & Kouno, ). Some deeper oxidation products and trimers of TFs were also identified in the in vitro reaction system based on tea polyphenols and horseradish peroxidase (Sang et al., ).…”

Section: Tea Chemistrymentioning

confidence: 99%

“…In brief, as shown in Figure 3, if we structurally consider the oxidation products or condensed compounds of catechins and other compounds formed during fermentation, TFs, isotheaflavins, and neotheaflavins are only one benzotropolone containing compounds by condensation of di-and tri-hydroxyls at the B-rings of flavan-3-ols (Davis, Cai, & Davies, 1995). Through continuous oxidation of tri-hydroxyls of gallate and di-hydroxyls of catechin, theadibenzotropolones and theatribenzotropolones containing two and three benzotropolones moieties formed, respectively, (Sang, Tian, Stark, Yang, & Ho, 2004). On the other hand, through decarboxylation, TFs can produce theanaphthoquinones and theacoumarins, which no longer have the benzotropolone moiety (Kusano, Matsuo, Saito, & Tanaka, 2015).…”

Section: Novel Flavan-3-ols Derivativesmentioning

confidence: 99%

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Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review

Liang

Zhou

et al. 2019

Comp Rev Food Sci Food Safe

341

237

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Tea is a typical processed beverage from the fresh leaves of Camellia sinensis [Camellia sinensis (L.) O. Kuntze] or Camellia assamica [Camellia sinensis var. assamica (Mast.) Kitamura] through different manufacturing techniques. The secondary metabolites of fresh tea leaves are mainly flavan‐3‐ols, phenolic acids, purine alkaloids, condensed tannins, hydrolysable tannins, saponins, flavonols, and their glycoside forms. During the processing, tea leaves go through several steps, such as withering, rolling, fermentation, postfermentation, and roasting (drying) to produce different types of tea. After processing, theaflavins, thearubigins, and flavan‐3‐ols derivatives emerge as the newly formed compounds with a corresponding decrease in concentrations of catechins. Each type of tea has its own critical process and presents unique chemical composition and flavor. The components among different teas also cause significant changes in their biological activities both in vitro and in vivo. In the present review, the progress of tea chemistry and the effects of individual unit operation on components were comprehensively described. The health benefits of tea were also reviewed based on the human epidemiological and clinical studies. Although there have been multiple studies about the tea chemistry and biological activities, most of existing results are related to tea polyphenols, especially (‐)‐epigallocatechin gallate. Other compounds, including the novel compounds, as well as isomers of amino acids and catechins, have not been explored in depth.

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Section: Tea Chemistrymentioning

confidence: 99%

Section: Novel Flavan-3-ols Derivativesmentioning

confidence: 99%

Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review

Liang

Zhou

et al. 2019

Comp Rev Food Sci Food Safe

341

237

View full text Add to dashboard Cite

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“…1). The thearubigins are oligomeric and polymeric polyphenolic compounds, which have only recently begun to be structurally characterized (3)(4)(5). Oolong tea is allowed to undergo partial oxidation, which results in the retention of higher levels of catechins than are found in black tea but also in the formation of unique dimeric and oligomeric polyphenols such as the theasinensins (Fig.…”

Section: Introductionmentioning

confidence: 99%

“…Chemically, green tea is characterized by the presence of large amounts polyphenols known as catechins (1). (-)-Epicatechin (EC), 3 (-)-epigallocatechin (EGC), (-)-epicatechin-3-gallate (ECG), and (-)-epigallocatechin-3-gallate (EGCG) are the major green tea catechins ( Fig. 1) (2).…”

Section: Introductionmentioning

confidence: 99%

Laboratory, Epidemiological, and Human Intervention Studies Show That Tea (Camellia sinensis) May Be Useful in the Prevention of Obesity ,

Grove

Lambert

2010

The Journal of Nutrition

153

102

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Tea (Camellia sinensis, Theaceae) and tea polyphenols have been studied for the prevention of chronic diseases, including obesity. Obesity currently affects >20% of adults in the United States and is a risk factor for chronic diseases such as type II diabetes, cardiovascular disease, and cancer. Given this increasing public health concern, the use of dietary agents for the prevention of obesity would be of tremendous benefit. Whereas many laboratory studies have demonstrated the potential efficacy of green or black tea for the prevention of obesity, the underlying mechanisms remain unclear. The results of human intervention studies are mixed and the role of caffeine has not been clearly established. Finally, there is emerging evidence that high doses of tea polyphenols may have adverse side effects. Given that the results of scientific studies on dietary components, including tea polyphenols, are often translated into dietary supplements, understanding the potential toxicities of the tea polyphenols is critical to understanding their potential usefulness in preventing obesity. In this review, we will critically evaluate the evidence for the prevention of obesity by tea, discuss the relevance of proposed mechanisms in light of tea polyphenol bioavailability, and review the reports concerning the toxic effects of high doses of tea polyphenols and the implication that this has for the potential use of tea for the prevention of obesity. We hope that this review will expose areas for further study and encourage research on this important public health issue.

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“…The dark brown cannot be explained by the presence of a proanthocyanidin polymer or a simple polymer with interflavonoid linkages of A-ring to B-ring and B-ring to B-ring. Although it was not clearly proved, we speculate that benzotropolone [26][27][28][29] and naphthoquinone structures 30) are present as chromophores in those polymers.…”

Section: Properties Of Mafs From Oolong Tea and Black Teamentioning

confidence: 75%

High-Molecular-Weight Polyphenols from Oolong Tea and Black Tea: Purification, Some Properties, and Role in Increasing Mitochondrial Membrane Potential

Fujihara

Nakagawa-Izumi

Ozawa

et al. 2007

Bioscience, Biotechnology, and Biochemistry

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High-molecular-weight polyphenols from oolong and black teas increased mitochondrial membrane potential, as measured by a method using ciliated protozoan Tetrahymena and rhodamine 123. These polyphenols, referred to as mitochondrial activation factors (MAFs), were purified from oolong and black teas by solvent extraction and Toyopearl column chromatography. The number-average molecular weights of the MAFs were 9,000 to 18,000, and the weight-average molecular weights were 15,000 to 25,000. The MAFs increased the mitochondrial membrane potential more than catechins did. Treatment of the MAFs with tannase indicated that they contained galloyl residues. When the MAFs were hydrolyzed with HCl-n-BuOH, cyanidin and delphinidin were detected. The partial structure of the MAFs was analyzed by pyrolysis-gas chromatography-mass spectrometry, and nine compounds were identified. These results suggest that MAFs are heterogeneous polymers of flavan-3-ols and flavan-3-ol gallates with intermonomeric linkages of B-ring to B-ring and C-ring to A-ring.

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New dibenzotropolone derivatives characterized from black tea using LC/MS/MS

Cited by 47 publications

References 25 publications

Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review

Chemistry and Biological Activities of Processed Camellia sinensis Teas: A Comprehensive Review

Laboratory, Epidemiological, and Human Intervention Studies Show That Tea (Camellia sinensis) May Be Useful in the Prevention of Obesity ,

High-Molecular-Weight Polyphenols from Oolong Tea and Black Tea: Purification, Some Properties, and Role in Increasing Mitochondrial Membrane Potential

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