Survey of Catechins, Gallic Acid, and Methylxanthines in Green, Oolong, Pu-erh, and Black Teas

Lin, Jen‐Kun; Lin, Chih‐Li; Liang, Yu‐Chih; Lin‐Shiau, Shoei‐Yn; Juan, I-Ming

doi:10.1021/jf980223x

Cited by 261 publications

(206 citation statements)

References 20 publications

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“…Dietary antioxidants are found in cereals, fruits, legumes, spices, vegetables and beverages (Ganthavorn & Hughes, 1997;Lin et al, 1998;Kalt et al, 1999;Ewald et al, 1999;Che Man & Tan, 1999;Markus et al, 1999). The contribution of total PPs to antioxidant capacity has been extensively studied in fruits and vegetables (Furuta et al, 1997;Gazzani et al, 1998;Heinonen et al, 1998;Saleh et al, 1998;Wang et al, 1999).…”

Section: Introductionmentioning

confidence: 99%

Contribution of beverages to the intake of lipophilic and hydrophilic antioxidants in the Spanish diet

2003

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Objective: To investigate the contribution of beverages to the intake of lipophilic and hydrophilic antioxidants in the Spanish diet. Design: This includes the following (i) estimation of the daily intakes of beverages in Spain, from national food consumption data obtained from annual surveys of 5400 households, 700 hotels and restaurants and 200 institutions; (ii) determination of total antioxidant capacity in the selected beverages using two complementary procedures: ferric reducing ability of plasma (FRAP), which measures the ferric reduction capacity, and ABTS, which measures the radical scavenging capacity; (iii) determination of the antioxidant capacity in both lipophilic and hydrophilic extracts of the beverages; (iv) determination of the antioxidant efficiency of the lipophilic and hydrophilic phase of the beverages; and (v) estimation of the intake of dietary antioxidants from beverages in comparison with the daily requirements of antioxidant vitamins C and E. Results: The contribution of beverages to the antioxidant intake in the Spanish diet is estimated at 1623 mg of vitamin E and 598 mg of vitamin C by FRAP, and 1521 mg of vitamin E and 556 mg of vitamin C by ABTS. Coffee is the main contributor (66 and 61% by FRAP and ABTS, respectively), followed by red wine (16 and 22%), fruit juices (6 and 5%), beer (4 and 5%), tea (3 and 5%) and milk (4 and 1%). Conclusions: Beverages account for a very high proportion of dietary antioxidant intake as compared to intake of antioxidant vitamins C and E. Although their metabolic effect must be affected by the bioavailability of the antioxidants, the significance of this intake for antioxidant status and health should be considered.

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Section: Introductionmentioning

confidence: 99%

Contribution of beverages to the intake of lipophilic and hydrophilic antioxidants in the Spanish diet

2003

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“…This indicated that gallic acid was the main radical scavenger in Toyama Kurocha. It has been reported that gallic acid is a main catechin of the late-fermented teas Kurocha and Pu-erh tea, and could be separated from (-)-epicatechin gallate while other catechins were polymerized during fermentation of the tea (Shojaku et al, 1984;Lin et al, 1998;Matsumoto et al, 1999). However, the radical scavenging activity of gallic acid in the late-fermented tea was not studied in these papers.…”

Section: Resultsmentioning

confidence: 99%

Radical Scavenging Activity of Japanese Black Tea, Toyama Kurocha.

Terasawa¹,

Yamazaki²

2002

FSTR

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The radical scavenging activity of the Japanese late-fermented black tea, Toyama Kurocha, was investigated. The activity was determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method, and its radical scavenging activity was found to be lower than that of green tea. Dried leaves of Toyama Kurocha were extracted in boiling distilled water for 10 min, the resulting extract was fractionated in the usual way, and the strongly acidic fraction was purified by silica gel column chromatography and HPLC. Five peaks of phenolics and 4 unknown peaks were detected by HPLC, and the main phenolics component in Toyama Kurocha was believed to be a gallic acid. Gallic acid has the highest DPPH radical scavenging activity.

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“…GOTO et al [11] acharam níveis comparáveis de EGC e EC, mas maiores de EGCG e ECG, enquanto DING et al [7] relataram níveis mais altos de EC, que foi a principal catequina, e ECG. LIN et al [19] apresentaram níveis nitidamente mais altos de ECG e menores de EGC. Por sua vez, SHAO et al [26] acharam ECG como principal catequina, além de conteúdos mais altos de EC.…”

Section: -Teores De Catequinasunclassified

Teores de catequinas e teaflavinas em chás comercializados no Brasil

Matsubara¹,

Rodriguez–Amaya²

2006

Ciênc. Tecnol. Aliment.

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* A quem a correspondência deve ser enviada RESUMONo presente estudo, foram determinados os teores de catequinas e teaflavinas em três marcas de chá verde e quatro de chá preto comercializadas no Brasil. A metodologia analítica consistiu de extração aquosa bastante simples e cromatografia líquida de alta eficiência. Foi utilizada uma coluna de fase reversa Novapak C 18 (3,9 mmx150 mm, 4 µm) com um gradiente de água e metanol ambos em ácido fórmico como fase móvel. Em chás verdes, os conteúdos de catequinas (em mg/g de folha seca) variaram substancialmente: catequina, 0,8 a 2,8; epigalocatequina, 8 a 44; epigalocatequina galato, 11 a 50; epicatequina, 2,3 a 8,5 e epicatequina galato, 3,1 a 7,3. No caso dos chás pretos, as concentrações (mg/g de folha seca) de catequinas estiveram nas faixas de: 10 a 50 de epigalocatequina, 14 a 37 de epigalocatequina galato, 5 a 9 de epicatequina e 10 a 21 de epicatequina galato. As teaflavinas apresentaram variação menor: entre 5 (para teaflavina 3'-galato) e 13 mg/g (para teaflavina 3,3'-digalato) de folha seca. Amostras de chás muito consumidas no Brasil (erva doce, camomila, erva cidreira, hortelã, boldo, mate, erva mate, maçã e morango) também foram investigadas, não sendo encontrada nenhuma catequina ou teaflavina. Palavras-chave: chá verde, chá preto, catequinas, teaflavinas, cromatografia líquida de alta eficiência. SUMMARY CATHECHIN AND THEAFLAVIN LEVELS OF TEAS COMMERCIALIZED IN BRAZILIn the present study, the catechin and theaflavin levels in three brands of green tea and four brands of black tea commercialized in Brazil were determined. The analytical methodology consisted of a very simple aqueous extraction and high performance liquid chromatography. A reverse phase Novapak C 18 (3.9 mmx150 mm, 4 µm) column was used with a gradient of water and methanol, both in formic acid, as mobile phase. In green tea, the catechin contents (in mg/g of dry leaf) varied substantially: catechin, 0.8 to 2.8; epigallocatechin, 8 to 44; epigallocatechin gallate, 11 to 50; epicatechin, 2.3 to 8.5; and epicatechin gallate, 3.1 to 7.3. In the case of black tea, the concentrations (mg/g of dry leaf) of catechins were in the ranges of: 10 to 50 of epigallocatechin, 14 to 37 of epigallocatechin gallate, 5 to 9 of epicatechin and 10 to 21 of epicatechin gallate. The theaflavins had less variation: between 5 (for theaflavin 3'-gallate) to 13 mg/g (for theaflavin 3,3'-digallate) of dry leaf. Samples of teas widely consumed in Brasil (anise, camomile, lemon grass, peppermint, boldo, maté, green maté, apple and strawberry) were also investigated but no catechin or theaflavin was detected.

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Survey of Catechins, Gallic Acid, and Methylxanthines in Green, Oolong, Pu-erh, and Black Teas

Cited by 261 publications

References 20 publications

Contribution of beverages to the intake of lipophilic and hydrophilic antioxidants in the Spanish diet

Contribution of beverages to the intake of lipophilic and hydrophilic antioxidants in the Spanish diet

Radical Scavenging Activity of Japanese Black Tea, Toyama Kurocha.

Teores de catequinas e teaflavinas em chás comercializados no Brasil

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