• Journal of Microbiology and Biotechnology
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• v.23 no.9
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• pp.1322-1326
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• 2013

New antifungal agents are required to compensate for the increase in resistance to standard antifungal agents of Candida albicans, which is an important opportunistic fungal pathogen that causes minor infections in many individuals but very serious infections in those who are immune-compromised. In this study, combinations of theaflavin and epicatechin are investigated as potential antifungal agents and also to establish whether antifungal synergy exists between these two readily accessible and cost-effective polyphenols isolated from black and green tea. The results of disc diffusion assays showed stronger antibacterial activity of theaflavin:epicatechin combinations against C. albicans NCTC 3255 and NCTC 3179, than that of theaflavin alone. Minimum inhibitory concentrations (MICs) of 1,024 ${\mu}g/ml$ with theaflavin and 128-256 ${\mu}g/ml$ with theaflavin:epicatechin combinations were found. The fractional inhibitory concentration indexes were calculated, and the synergy between theaflavin and epicatechin against both isolates of C. albicans was confirmed. Theaflavin:epicatechin combinations show real potential for future use as a treatment for infections caused by C. albicans.

• Food Industry And Nutrition
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• v.11 no.3
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• pp.44-48
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• 2006

본 연구는 옻(Rhus verniciflua)에 대한 국산 미생물 발효차 폴리 페놀물질 인 theaflavin(TF)과 thearubigin(TR)의 항알레르기 효과를 조사하였다. HPLC, column chromatography 및 TLC로 이용하여, 한국 원주산, 일본산 및 중국산 락커(lacquer)로부터 아주 강한 알레르기를 유발하는 long chain alkylphenol을 함유하는 crude urushiol 성분을 분리하였다. 고분자 이중 및 삼중불포화물질의 함량은 중국산 라커의 crude urushiol에 가장 많이 포함되어 있었다. 중국산 라커의 crude urushiol에서 유발되는 접촉성 알레르기 피부염 발생은 5%농도에서 한국산이나 일본산 라커의 시료보다 높았으며, TF 및 TR를 처리한 모든 농도에서 접촉성 알레르기 피부염의 유의적인 감소를 나타내었다. 이들 결과로부터 발효차의 폴리페놀성 TF와 TR은 옻의 접촉성 피부염에 대한 유의적인 항알레르기 효과를 나타내었다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3774-3780
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• 2014

This study examined green tea fermented by the addition of sun-dried salt to increase the extraction of Procyanidins and Gallic acid and Theaflavins. An experiment on the change in the amount of the extract according to the saturation degree of sun-dried salt was performed. The sample of fermented only green tea extracted only Gallic acid (0.004 mg/g). No Procyanidins and Theaflavins were extracted. When the green tea was fermented by sun-dried salt, large amounts of the three compounds were extracted: Procyanidins, 75%(0.244 mg/g) and 100%(0.949 mg/g); Gallic acid, 75%(0.386 mg/g) and 100%(0.691 mg/g), and Theaflavins, 75%(0.083 mg/g). According to the date of fermentation, the largest amount of Procyanidins, Gallic acid and Theaflavins extracted were on the 2nd day(0.295 mg/g) and 7th day(2,256 mg/g) and 4th day(0.168 mg/g), respectively.

• Preventive Nutrition and Food Science
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• v.12 no.3
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• pp.135-140
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• 2007

Antibacterial activities of the major phenolic components from Camellia sinensis L. were investigated against several pathogenic microorganisms including Gram-positive strains like Staphylococcus aureus ATCC 29213 and Streptococcus pyogens 308A; and Gram-negative strains like Escherichia coli ATCC 25922, Escherichia coli 078, Pseudomonas aeruginosa 9027, and Enterobacter cloacae 1321E. The MIC values demonstrate that both (-)-epicatechin and (-)-epigallocatechin were more considerably toxic against Staphylococcus aureus ATCC 29213 than the other two catechins like (-)-epicatechingallate and (-)-epigallocatechin-3-gallate. (-)-Epicatechingallate and (-)-epigallocatechin-3-gallate were most inhibitory against Escherichia coli ATCC 25922. As a result, (-)-epicatechin showed predominant antibacterial activities among tea varieties. The contents of major polyphenolic components such as four catechins, theaflavin, and quercetin were different according to fermentation processes. The total contents of four catechins were ranged from 13.81 to 1.33%, with (-)-epigallocatechin-3-gallate being dominant among tea varieties; theaflavin was found the characteristic pigment in fully-fermented black tea.

• Journal of Applied Biological Chemistry
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• v.55 no.1
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• pp.19-25
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• 2012

Green tea leaves were fermented for 15 and 30 days with Monascus pilosus which is known to produce functional statins (TMs), and the content of various biochemical constituents such as total polyphenol (TP), total flavonoid (TF), theaflavin, and thearubigin were analyzed and compared with that of non-fermented green tea (GT) and Pu-erh Chinese post-fermented tea (PU). In addition to the electron donating ability (EDA), ferric iron reducing power (FIRP), xanthine oxidase (XO) inhibitory activity, superoxide dismutase (SOD)-like activity, iron chelating activity (ICA) and hydrogen peroxide contents were also measured and compared with that of GT and PU. Content of TP and TF in the water and ethanol extracts in TMs were lower than those in GT and PU. Theaflavin and thearubigin contents of water and ethanol extracts in TMs were higher than those of GT. And, these components were increased depending on the period of fermentation. While, EDA and FIRP of TMs were lower than those of GT, XO inhibitory activity of TMs was higher than non-fermented tea. While, ICA of TMs was slightly higher than GT and PU, the content of hydrogen peroxide in TMs was markedly lower than GT. This results suggested that the green tea fermented by M. pilosus was valuable for oxidative stress-induced diseases by decreasing hydrogen peroxide, and forming theaflavins and thearubigins with functionality of genus Monascus.

• Archives of Pharmacal Research
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• v.25 no.5
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• pp.561-571
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• 2002

The action mechanisms of several chemopreventive agents derived from herbal medicine and edible plants have become attractive issues in cancer research. Tea is the most widely consumed beverage worldwide. Recently, the cancer chemopreventive actions of tea have been intensively investigated. It have been demonstrated that the active principles of tea were attributed to their tea polyphenols. Recently, tremendous progress has been made in elucidating the molecular mechanisms of cancer chemoprevention by tea and tea polyphenols. The suppression of various tumor biomarkers including growth factor receptor tyrosine kinases, cytokine receptor kinases, P13K, phosphatases, ras, raf, MAPK cascades, NㆍFB, IㆍB kinase, PKA, PKB, PKC, c-jun, c-fos, c-myc, cdks, cyclins, and related transducing proteins by tea polyphenols has been studied in our laboratory and others. The IㆍB kinase (IKK) activity in LPS-activated murine macrophages (RAW 264.7 cells) was found to be inhibited by various tea polyphenols including (-) epigallocatechin-3-gallate (EGCG), theaflavin (TF-1), theaflavin-3-gal-late (TF-2) and theaflavin-3,3'-digallate (TF-3). TF-3 inhibited IKK activity in activated macrophages more strongly than did the other tea polyphenols. TF-3 inhibited both IKK1 and IKK2 activity and prevented the degradation of IㆍBㆍand IㆍBㆍin activated macrophage cells. The results suggested that the inhibition of IKK activity by TF-3 and other tea polyphenols could occur by a direct effect on IKKs or on upstream events in the signal transduction pathway. TF-3 and other tea polyphenols blocked phosphorylation of IB from the cytosolic fraction, inhibited NFB activity and inhibited increases in inducible nitric oxide synthase levels in activated macrophage. TF-3 and other tea polyphenols also inhibited strongly the activities of xanthine oxidase, cyclooxygenase, EGF-receptor tyrosine kinase and protein kinase C. These results suggest that TF-3 and other tea polyphenols may exert their cancer chemoprevention through suppressing tumor promotion and inflammation by blocking signal transduction. The mechanisms of this inhibition may be due to the blockade of the mitogenic and differentiating signals through modulating EGFR function, MAPK cascades, NFkB activation as wll as c-myc, c-jun and c-fos expression.

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.16-23
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• 1986

Physico-chemical and sensory characteristics of 28 black tea samples prepared by oaring the mixing ratio of 1 kind of Korean and 9 kinds of foreign black tea were determined, and their relationship was statistically analysed. Korean black tea was found to be lower in bulk density, caffeine, theobromine, crude protein, theaflavin, thearubigin and soluble solids, and higher in Hunter L- and b- value, neutral detergent fiber, calcium and ratio of oxidized matter as compared with foreign black tea. The palatability for 8 kinds of foreign black tea was generally increased by mixing with Korean black tea. The number of black tea whose palatability were higher than that of Korean black tea was 12, which was mostly mixed black tea. Theaflavin. Hunter a-value, soluble solids of the tea infusion, and potassium of the manufactured tea were the major guiding characteristics as a result of stepwise multiple regression analysis, and about 67% of the total variations in the palatability of black tea could be explained by the regression equation formulated by the preceding 4 characteristics.

• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.346-353
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• 2005

CThis study used HPLC to analyze the contents of 7 kinds of catechins, 4 kinds of theaflavins, and 2 kinds of methylxanthines in the following 6 kinds of commercial Korean tea: 2 green, 2 black, 1 jasmine and loolong. The following ranges in the 13 tea components of the 6 samples by ethanol extract were evaluated in mg/g: (-)-epigallocatechin, 0(black tea and jasmine tea) to 14.19(green tea); (-)-catechin 0; (+)-epicatechin, 0.62(bran rice-green tea) to 2.91(black tea); (-)-epigallocatechin gallate, 4.59(black tea) to 43.96(jasmine tea); (-)-gallocatechin gallate, 0.58(black tea) to 5.80(jasmine tea); (-)-epicatechin gallate, 5.63(bran rice-ueen tea) to 48.06(jasmine tea): (-)-catechin gallate, 0.26(black tea): theaflavif 0 to 3.66(black tea): theaflavin-3-gallate, 0 to 6.94(black tea): theaflavin-3'-gallate, 0 to 4.01(black tea); theaflavin-3,3-digallte, 0 to 10.25(black tea); caffeine, 4.60(bran rice-peen tea) to 26.44(black tea); and theobromine, 0.10(bran rice-green tea) to 1.81(jasmine tea). The contents of all components were lower by water extract than by ethanol extract. Therefore, total catechin (100.55, 45.88 mg/g) and theobromine (1.81, 0.86 mg/g) contents in jasmine tea, and theaflavin content (24.88, 1.36 mg/g) in black tea by ethanol and water extract were the highest. Caffeine content was the highest in black tea(96.48 mg/g) for the ethanol extract, and in jasmine tea (12.38 mg/g) for the water extract.

• Journal of the Korean Society of Clothing and Textiles
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• v.22 no.4
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• pp.477-481
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• 1998

Colored components in black tea were extracted, freeze-dried, and analysed to investigate the possibility using as a natural dye. Fractionation of the colored components was carried out by gel permeation chromatography. The colored components in black tea were elected into seven fractions. Each fraction was analyzed by UV spectrophotometer. The early fluted fractions 1-4 did not show any absorption peaks in 320-700 nm and showed the increase in absorption as it approaches to short wavelength and are considered as highly polymerized colored substances. Fractions 5-6 showed tar at 350 m and are considered as thearubigins. Fraction 7 showed absorption peaks at 376 nm and 456 nm and is considered as theaflavin. IR spectra of each fraction show: Strong C=0 stretching band at 1650 cm-1 appears in fractions 1-4, but not in fractions 5-7. Strong C=0 stretching band at 1700 cm-L appears in fraction 3-7. C=0 stretching band at 1610 cm-1 appears as a shoulder in fraction 4 and progressively changes into strong peak in fraction 5-7. From these results, it is assumed that colored components in black tea consist of polyphenolic substances having different molecular weight which were formed during tea manufacturing process. The colorants from black tea infusion were applied to silk, wool, cotton and nylon fabrics. Black tea colorants showed high affinity to wool, silk and nylon, but very low affinity to cotton fabrics.

• Food Science and Biotechnology
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• v.16 no.1
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• pp.167-170
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• 2007

(-)-Epigallocatechin-3-gallate (EGCG), a mai or tea catechin has been shown to have many interesting biological activities. In the present study, we studied the effects of green tea catechins, EGCG metabolites, and black tea theaflavins on accumulation of EGCG in HT-29 human colon cells. Intracellular levels of [$^3H$]-EGCG were not changed significantly in the presence of other tea catechins including (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin-3-gallate. EGCG methyl metabolites and EGCG 4"-glucuronide did not affect cellular levels of [$^3H$]-EGCG. Black tea theaflavins and theasinensin A (TsA), an EGCG oxidative dimer, however, significantly decreased cellular accumulation of EGCG in HT-29 cells by 31-56%. This decrease was more pronounced when cells were incubated in the presence of theaflavin-3',3"-digallate (TFdiG) or TsA. When EGCG was added separately from TFdiG or TsA, the accumulation of EGCG in HT-29 cells was also significantly decreased regardless of when TFdiG or TsA was added during the uptake study (p<0.01). The results suggest that theaflavins and TsA may interrupt EGCG absorption through the gastrointestinal epithelium.