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Sample records for tea catechins caffeine

  1. Quantification of catechins and caffeine from green tea (Camellia sinensis infusions, extract, and ready-to-drink beverages

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    Rafaela Macedo Mendes De Oliveira

    2012-03-01

    Full Text Available This study aimed to quantify the levels of catechins and caffeine in various forms of presentation of green tea: infusion tea bags, extract, and ready-to-drink beverage and, based on their content, identify the most suitable for consumption. High Performance Liquid Chromatography (HPLC analytical method was used for the quantification of catechins and caffeine. The tea bags had the highest concentration of total catechins with 5 to 9.5% followed by the extract with 3.64 to 4.88%, and ready-to-drink green tea beverage showed low levels of catechins, from 0.14 to 0.26%. As for caffeine content, green tea extract had higher concentration (1.96 to 3.54% compared to the tea bags (1.39 to 1.57%. Tea bags were found the most suitable for consumption because it contains higher amounts of catechins and smaller amounts of caffeine.

  2. New Approaches for Effective Microwave Assisted Extraction of Caffeine and Catechins from Green Tea

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    Gönül SERDAR

    2016-01-01

    Full Text Available This study was designed to develop an effective microwave assisted extraction (MAE method for extraction of caffeine and catechins from green tea samples. A series of solvents (water, ethanol:water mixture or citric acid:water mixture were used for extraction of green tea samples (fresh, frozen or dried collected in three collection periods (first, second and third collection periods. Tea samples were extracted using water in a close microwave system under the certain extraction conditions. Extraction was carried out under a controlled 600 W microwave power at 80 oC temperature for 4 min irradiation time. Alternative to water, an ethanol-water mixture (1:1 or a citric acid-water (1:1 mixture was used as extracting solvent under the same conditions. After MAE crude aqueous extract was partitioned first with chloroform to separate caffeine then ethyl acetate for catechins.  Both caffeine and catechin extraction was quite successful with microwave assisted system employing only 4 minutes treatment. The highest caffeine yield was obtained in the second collection period using frozen green tea samples and ethanol-water as extracting solvent. The yield of catechin extracts was between 0.84-3.96% depending on the solvent system used for extraction. Ethanol-water mixture seems to be appropriate for effective extraction in the basis of extract yields. However, HPLC results showed that individual catechin content of each extraction is more important criteria for the evaluation of most effective extraction medium rather than the mass of the extract.  Using citric acid as extracting solvent in MAE seem to be more fruitful providing 100% catechin mixture with the highest EGCG content. 

  3. Comparison of Some Extraction Methods for Isolation of Catechins and Caffeine from Turkish Green Tea

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    Ezgi DEMİR

    2015-07-01

    Full Text Available Effective extraction of anticancer and antioxidant principles from Turkish green tea were main purpose of this work. The pre-optimized experimental condition for liquid extraction was employed for comparative appraisal.  Not only extraction methods also nature of the green tea samples (fresh, dried or frozen and quantitative yields related to collection periods were investigated.  After extraction of the green tea with various techniques the extract was partitioned with chloroform to remove caffeine, after that the extract was partitioned with ethyl acetate to obtain catechin mixture. Quantification of individual catechins was carried out by HPLC and analysis results proved that epigallocatechin gallate (EGCG was main catechin specie present in all extracts. The results indicate that hot water extraction (at 80 0C provides higher catechin yield when compared to other methods. The highest extract yields were obtained with dried leaves collected in second collection period. The crude catechin mixture contains high amount of EGCG and might be used as raw material for production of plant remedies at industrial scale.

  4. Effect of moderate intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions

    DEFF Research Database (Denmark)

    Gregersen, N.T.; Bitz, C.; Krog-Mikkelsen, I.

    2009-01-01

    Green tea may stimulate energy metabolism; however, it is unclear if acute effects are caused by specific catechins, caffeine or their combination. The objective of the present study was to examine the separate and combined effects of different catechins and caffeine on energy expenditure (EE......) and fat oxidation over a single day. Fifteen healthy, normal-weight males received capsules containing placebo, caffeine alone (150mg), or caffeine plus a catechin mixture (600 mg) enriched in either epigallocatechin-3-gallate (EGCG), epigallocatechin or a mix of catechins, in a randomised cross......-over double-blinded design. On each test day EE, respiratory quotient (RQ) and substrate oxidation were measured under sedentary conditions in a respiratory chamber for 13.5h. We found no significant treatment effect on EE (P=0.20) or RQ (P=0.68). EGCG with caffeine insignificantly raised EE and fat oxidation...

  5. Effect of moderate intakes of different tea catechins and caffeine on acute measures of energy metabolism under sedentary conditions.

    Science.gov (United States)

    Gregersen, Nikolaj T; Bitz, Christian; Krog-Mikkelsen, Inger; Hels, Ole; Kovacs, Eva M R; Rycroft, Jane A; Frandsen, Erik; Mela, David J; Astrup, Arne

    2009-10-01

    Green tea may stimulate energy metabolism; however, it is unclear if acute effects are caused by specific catechins, caffeine or their combination. The objective of the present study was to examine the separate and combined effects of different catechins and caffeine on energy expenditure (EE) and fat oxidation over a single day. Fifteen healthy, normal-weight males received capsules containing placebo, caffeine alone (150 mg), or caffeine plus a catechin mixture (600 mg) enriched in either epigallocatechin-3-gallate (EGCG), epigallocatechin or a mix of catechins, in a randomised cross-over double-blinded design. On each test day EE, respiratory quotient (RQ) and substrate oxidation were measured under sedentary conditions in a respiratory chamber for 13.5 h. We found no significant treatment effect on EE (P = 0.20) or RQ (P = 0.68). EGCG with caffeine insignificantly raised EE and fat oxidation v. caffeine-only and placebo (EE 5.71 (SE 0.12) v. 5.68 (SE 0.14) v. 5.59 (SE 0.13) MJ/12.5 h, respectively; fat oxidation 84.8 (SE 5.2) v. 80.7 (SE 4.7) v. 76.8 (SE 4.0) g/12.5 h). Catechin/caffeine combinations at these dosages and mode of application had non-significant acute effects on EE and fat oxidation. The maximum observed effect on EE of about 2 % could still be meaningful for energy balance over much longer period of exposure. However, higher short-term effects reported in the literature may reflect variations in green tea extracts, added caffeine, or synergies with physical activity. The specific mechanisms and conditions that may underpin observed longer-term benefits of catechin-enriched green tea consumption on body composition remain to be confirmed.

  6. Rapid tea catechins and caffeine determination by HPLC using microwave-assisted extraction and silica monolithic column.

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    Rahim, A A; Nofrizal, S; Saad, Bahruddin

    2014-03-15

    A rapid reversed-phase high performance liquid chromatographic method using a monolithic column for the determination of eight catechin monomers and caffeine was developed. Using a mobile phase of water:acetonitrile:methanol (83:6:11) at a flow rate of 1.4 mL min(-1), the catechins and caffeine were isocratically separated in about 7 min. The limits of detection and quantification were in the range of 0.11-0.29 and 0.33-0.87 mg L(-1), respectively. Satisfactory recoveries were obtained (94.2-105.2 ± 1.8%) for all samples when spiked at three concentrations (5, 40 and 70 mg L(-1)). In combination with microwave-assisted extraction (MAE), the method was applied to the determination of the catechins and caffeine in eleven tea samples (6 green, 3 black and 2 oolong teas). Relatively high levels of caffeine were found in black tea, but higher levels of the catechins, especially epigallocatechin gallate (EGCG) were found in green teas. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Effect of green tea catechins with or without caffeine on anthropometric measures: a systematic review and meta-analysis.

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    Phung, Olivia J; Baker, William L; Matthews, Leslie J; Lanosa, Michael; Thorne, Alicia; Coleman, Craig I

    2010-01-01

    Green tea catechins (GTCs) with or without caffeine have been studied in randomized controlled trials (RCTs) for their effect on anthropometric measures and have yielded conflicting results. The objective was to perform a systematic review and meta-analysis of RCTs of GTCs on anthropometric variables, including body mass index (BMI), body weight, waist circumference (WC), and waist-to-hip ratio (WHR). A systematic literature search of MEDLINE, EMBASE, CENTRAL, and the Natural Medicines Comprehensive Database was conducted through April 2009. RCTs that evaluated GTCs with or without caffeine and that reported BMI, body weight, WC, or WHR were included. The weighted mean difference of change from baseline (with 95% CIs) was calculated by using a random-effects model. Fifteen studies (n = 1243 patients) met the inclusion criteria. On meta-analysis, GTCs with caffeine decreased BMI (-0.55; 95% CI: -0.65, -0.40), body weight (-1.38 kg; 95% CI: -1.70, -1.06), and WC (-1.93 cm; 95% CI: -2.82, -1.04) but not WHR compared with caffeine alone. GTC ingestion with caffeine also significantly decreased body weight (-0.44 kg; 95% CI: -0.72, -0.15) when compared with a caffeine-free control. Studies that evaluated GTCs without concomitant caffeine administration did not show benefits on any of the assessed anthropometric endpoints. The administration of GTCs with caffeine is associated with statistically significant reductions in BMI, body weight, and WC; however, the clinical significance of these reductions is modest at best. Current data do not suggest that GTCs alone positively alter anthropometric measurements.

  8. Beverages containing soluble fiber, caffeine, and green tea catechins suppress hunger and lead to less energy consumption at the next meal.

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    Carter, Brett E; Drewnowski, Adam

    2012-12-01

    Previous research has shown that beverages containing soluble fibers can decrease energy intake at the next meal among normal weight participants. Caffeine and green tea catechins have separately been associated with increased satiety. The present study examined the satiating power of a beverage containing soluble fiber as well as a beverage containing the same fiber, caffeine and green tea catechins. These two test beverages were evaluated in comparison to an equal calorie control beverage as well as a no-beverage control condition. All beverage preloads were presented three times for a total of 0.28-0.35MJ and 0-30g fiber. Dependent measures were appetite ratings and calorie intake at a test meal. The no-beverage condition was associated with the highest ratings for hunger and the lowest ratings for fullness when compared to the other three beverage conditions. Of the three beverage conditions, the beverage containing the fiber, green tea catechins, and caffeine created the lowest hunger and the highest fullness ratings. That condition was also associated with the lowest energy intake at the next meal. The present findings indicate that the beverage containing caffeine and green tea catechins in combination with soluble fiber decrease appetite and energy intake relative to a beverage with equal caloric content. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Quantification of total polyphenols, catechin, caffeine, L-theanine, determination of antioxidant activity and effect on antileishmanial drugs of ethiopian tea leaves extracts.

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    Tadesse, Alemu; Hymete, Ariaya; Bekhit, Adnan A; Mohammed, Salahuddin Farooq

    2015-06-01

    In this study four tea samples Gumero black, Wushwush black and Wushwush green from Agri- Ceft Plc and East Africa black tea leaves from East African Agribusiness Plc were investigated for total polyphenols, caffeine, catechin and L-theanine content. The aqueous extracts were investigated for their antioxidant and antileishmanial property and effect on amphotericin B, miltefocine and sodium stibogluconate, the commonly used antileishmanial drugs. Antileishmanial studies were conducted on L. aethiopica. Wushwush green tea had the highest content of polyphenol (19.98 ± 1.15 mg gallic acid equivalent /100 g dry leaf weight), catechin (37.06 mg/g) and L-theanine (48.54 mg/g but the lowest caffeine content). It exhibited the highest antioxidant activity. The highest antioxidant effect of Wushwush green tea may be attributed to the highest polyphenol content. East African black tea had the lowest L-theanine (20.72 mg/g) and antioxidant activity but the highest caffeine (16.60 mg/g) content. Wushwush green tea showed slight inhibitory effect on L. aethiopica while the lack tea extracts (Gumero, East Africa and Wushwush) exhibited no antileishmanial activity. Wushwush green tea did not show any synergistic or antagonistic effect on the antileishmanial drugs used in this study while Gumero, East Africa and Wushwush black tea extracts exhibited dose dependant inhibitory activity to the commonly used antileishmanial drugs included in this study.

  10. Quantification of total polyphenols, catechin, caffeine, L-theanine, determination of antioxidant activity and effect on antileishmanial drugs of ethiopian tea leaves extracts

    OpenAIRE

    Tadesse, Alemu; Hymete, Ariaya; Bekhit, Adnan A.; Mohammed, Salahuddin Farooq

    2015-01-01

    Objective: In this study four tea samples Gumero black, Wushwush black and Wushwush green from Agri- Ceft Plc and East Africa black tea leaves from East African Agribusiness Plc were investigated for total polyphenols, caffeine, catechin and L-theanine content. Materials and Methods: The aqueous extracts were investigated for their antioxidant and antileishmanial property and effect on amphotericin B, miltefocine and sodium stibogluconate, the commonly used antileishmanial drugs. Antileishman...

  11. Determination of volatile organic compounds, catechins, caffeine and theanine in Jukro tea at three growth stages by chromatographic and spectrometric methods.

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    Jeon, Dong Bok; Hong, Young Shin; Lee, Ga Hyun; Park, Yu Min; Lee, Cheong Mi; Nho, Eun Yeong; Choi, Ji Yeon; Jamila, Nargis; Khan, Naeem; Kim, Kyong Su

    2017-03-15

    Tea contains characteristic volatile organic compounds, polyphenols, caffeine and catechins, and is therefore among the most widely consumed beverages all over the world. In this study, fresh Jukro tea leaves collected from Damyang-gun (Jeollanam-do) at 40, 60 and 90day growth stages, were semi-fermented. The volatile organic compounds (VOCs) were extracted by simultaneous distillation-solvent extraction (SDE) and analyzed by gas chromatography/mass spectrometry (GC/MS). Catechins, caffeine and theanine were analyzed by high performance liquid chromatography (HPLC). A total of 159 VOCs were identified in the analyzed Jukro tea leaves. Comparatively, the increase in the concentrations of VOCs was high in 60day leaves. The content of catechins increased along the three growth stages, whereas caffeine, compared to 90day leaves, was higher for 40 and 60day leaves. Based on the results, the 60day leaves were found to be the most suitable and useful for making semi-fermented Jukro tea. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Rapid HPLC-MS method for the simultaneous determination of tea catechins and folates.

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    Araya-Farias, Monica; Gaudreau, Alain; Rozoy, Elodie; Bazinet, Laurent

    2014-05-14

    An effective and rapid HPLC-MS method for the simultaneous separation of the eight most abundant tea catechins, gallic acid, and caffeine was developed. These compounds were rapidly separated within 9 min by a linear gradient elution using a Zorbax SB-C18 packed with sub 2 μm particles. This methodology did not require preparative and semipreparative HPLC steps. In fact, diluted tea samples can be easily analyzed using HPLC-MS as described in this study. The use of mass spectrometry detection for quantification of catechins ensured a higher specificity of the method. The percent relative standard deviation was generally lower than 4 and 7% for most of the compounds tested in tea drinks and tea extracts, respectively. Furthermore, the method provided excellent resolution for folate determination alone or in combination with catechins. To date, no HPLC method able to discriminate catechins and folates in a quick analysis has been reported in the literature.

  13. Suppressive Effects of Tea Catechins on Breast Cancer

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    Xiang, Li-Ping; Wang, Ao; Ye, Jian-Hui; Zheng, Xin-Qiang; Polito, Curt Anthony; Lu, Jian-Liang; Li, Qing-Sheng; Liang, Yue-Rong

    2016-01-01

    Tea leaf (Camellia sinensis) is rich in catechins, which endow tea with various health benefits. There are more than ten catechin compounds in tea, among which epigallocatechingallate (EGCG) is the most abundant. Epidemiological studies on the association between tea consumption and the risk of breast cancer were summarized, and the inhibitory effects of tea catechins on breast cancer, with EGCG as a representative compound, were reviewed in the present paper. The controversial results regarding the role of tea in breast cancer and areas for further study were discussed. PMID:27483305

  14. Nutraceuticals for body-weight management: The role of green tea catechins.

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    Janssens, Pilou L H R; Hursel, Rick; Westerterp-Plantenga, Margriet S

    2016-08-01

    Green tea catechins mixed with caffeine have been proposed as adjuvants for maintaining or enhancing energy expenditure and for increasing fat oxidation, in the context of prevention and treatment of obesity. These catechins-caffeine mixtures seem to counteract the decrease in metabolic rate that occurs during weight loss. Their effects are of particular importance during weight maintenance after weight loss. Other metabolic targets may be fat absorption and the gut microbiota composition, but these effects still need further investigation in combination with weight loss. Limitations for the effects of green tea catechins are moderating factors such as genetic predisposition related to COMT-activity, habitual caffeine intake, and ingestion combined with dietary protein. In conclusion, a mixture of green tea catechins and caffeine has a beneficial effect on body-weight management, especially by sustained energy expenditure, fat oxidation, and preservation of fat free body-mass, after energy restriction induced body-weight loss, when taking the limitations into account. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Effects of catechins and caffeine on the development of atherosclerosis in mice.

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    Liu, Litong; Nagai, Izumi; Gao, Ying; Matsushima, Yoshibumi; Kawai, Yoshichika; Sayama, Kazutoshi

    2017-10-01

    Atherosclerosis is one of the diseases related to metabolic syndrome which is caused by obesity. Previous reports have shown that green tea and its components have anti-obesity effect. We examined whether catechins and caffeine can prevent the development of atherosclerosis by oral administration, singly or in combination to the atherosclerosis model mice. Results demonstrated that the number of atherosclerotic regions in the aorta was significantly reduced by the combined treatment, and the atherosclerotic area was also improved. Serum HDL-C increased by caffeine single treatment, but no effect on the TG and TC by any treatments. Moreover, ECG illuviated to atheromatous lesions in aorta and the illuviation was enhanced by caffeine. The mRNA expression levels of LOX-1 and TNF-α showed a tendency to suppress by the combined treatment. These results indicated that the combined administration of catechins and caffeine has the inhibitory effect on the development of atherosclerosis in mice.

  16. Diversity of catechin in northeast Indian tea cultivars.

    Science.gov (United States)

    Sabhapondit, Santanu; Karak, Tanmoy; Bhuyan, Lakshi Prasad; Goswami, Bhabesh Chandra; Hazarika, Mridul

    2012-01-01

    Tea (Camellia sinensis L.) leaf contains a large amount of catechins (a group of very active flavonoids) which contribute to major quality attributes of black tea. Based on morphological characters tea plants were classified as Assam, China, and Cambod varieties. The present study is an attempt for biochemical fingerprinting of the tea varieties based on catechin composition in green leaf of cultivars grown in Northeast India. Assam variety cultivars contained the highest level of catechins followed by Cambod and China. The average catechin contents were 231 ± 7 mg g(-1), 202 ± 5 mg g(-1), and 157 ± 4 mg g(-1) of dry weight of green leaf for Assam, Cambod, and China cultivars, respectively. Among the individual catechins the variations in epigallocatechin gallate (EGCG) and epigallocatechin (EGC) were the most prominent among the varieties. High EGC content was found to be a characteristic of Assam variety which was further corroborated through multivariate analysis.

  17. Methylxanthines and catechines in different teas (Camellia sinensis L. Kuntze – influence on antioxidant properties

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    Július Árvay

    2017-01-01

    Full Text Available In general, there are four basic types of tea: green (not fermented, black (fermented, oolong and white tea (partially fermented. The differences among these types are in the processing technology, which is largely reflected in their chemical composition. The most influential factor that significantly affects the quality and quantity of substances (biologically active is the processing temperature, which causes changes in the composition (isomerization and/or transformation. The present paper focuses on monitoring content of three methylxanthines - alkaloids (caffeine, theophylline and theobromine, and seven flavan-3-ols - catechins ((+-catechin (C, (--catechin-3-gallate (C-3-G, (--epicatechin (EC, (--epicatechin-3-gallate (EC-3-G, (--epigallocatechin-3-gallate (EGC-3-G, (--gallocatechin (GC and (--gallocatechin-3-gallate (GC 3-G, which are characteristic for tea. Attention was also given to the assessment of selected antioxidant parameters using spectrophotometric procedures (ABTS - radical cation decolorization assay and Phosphomolybdenum reducing antioxidant power assay in relation to the determined substances using RP-HPLC/DAD analysis. Based on the results obtained, it can be concluded that a type of tea clearly affects the quality and quantity of the substances that have a positive impact on the consumer's health, significantly reflected in the levels of antioxidant active substances determined by the spectrophotometric procedures. The highest content of methylxanthin, catechins, polyphenols and antioxidant substances was recorded in the green tea sample GT3. The highest content of flavonoids and phenolic acids was recorded in the Pu-erh tea sample PT 5.

  18. Stability of Green Tea Catechins in Commercial Tea Leaves during Storage for 6 Months

    Science.gov (United States)

    To help meet the needs of consumers, producers of dietary tea products, and researchers for information on health-promoting tea ingredients, we determined by HPLC seven catechins [(–)-epigallocatechin (EGC), (–)-catechin (C), (+)-epicatechin (EC), (–)-epigallocatechin 3-gallate (EGCG), (–)-gallocate...

  19. Diversity of Catechin in Northeast Indian Tea Cultivars

    Science.gov (United States)

    Sabhapondit, Santanu; Karak, Tanmoy; Bhuyan, Lakshi Prasad; Goswami, Bhabesh Chandra; Hazarika, Mridul

    2012-01-01

    Tea (Camellia sinensis L.) leaf contains a large amount of catechins (a group of very active flavonoids) which contribute to major quality attributes of black tea. Based on morphological characters tea plants were classified as Assam, China, and Cambod varieties. The present study is an attempt for biochemical fingerprinting of the tea varieties based on catechin composition in green leaf of cultivars grown in Northeast India. Assam variety cultivars contained the highest level of catechins followed by Cambod and China. The average catechin contents were 231 ± 7 mg g−1, 202 ± 5 mg g−1, and 157 ± 4 mg g−1 of dry weight of green leaf for Assam, Cambod, and China cultivars, respectively. Among the individual catechins the variations in epigallocatechin gallate (EGCG) and epigallocatechin (EGC) were the most prominent among the varieties. High EGC content was found to be a characteristic of Assam variety which was further corroborated through multivariate analysis. PMID:22448135

  20. Caffeine Content of Tea and Coffee

    African Journals Online (AJOL)

    1974-03-13

    Mar 13, 1974 ... The xanthines (caffeine, theophylline, and theobromine) occur in plants widely distributed throughout the world. Best known for the preparation of beverages are coffee beans which contain caffeine, tea leaves which contain caffeine and theophylline, and cocoa seeds which contain caffeine and ...

  1. A RP-HPLC method for the determination of tea catechins

    NARCIS (Netherlands)

    Khokhar, S.; Venema, D.; Hollman, P.C.H.; Dekker, M.; Jongen, W.M.F.

    1997-01-01

    An HPLC method with gradient elution for the quantification of catechins ((−)-epigallocatechin (EGC), ( )-catechin (C), (−)-epicatechin (EC), (−)-epigallocatechingallate (EGCg) and (−)-epicatechingallate (ECg)) in tea was developed. The method was used to determine catechins in black tea, green tea

  2. Effect of ultraviolet B irradiation on accumulation of catechins in tea ...

    African Journals Online (AJOL)

    Effect of UV-B irradiation time on accumulation of foliar catechins in two tea cultivars was investigated. Low influence rate and short term irradiation of UV-B stimulated accumulation of major tea catechins, resulting in an increase in level of total catechins. Excessive irradiation of UV-B supressed the accumulation of tea ...

  3. Determination of catechins and caffeine in camillia sinensis raw materials, extracts, and dietary supplements by HPLC-uv: single-laboratory validation.

    Science.gov (United States)

    Roman, Mark C

    2013-01-01

    A rapid method has been developed to quantify seven catechins and caffeine in green tea (Camillia sinensis) raw material and powdered extract, and dietary supplements containing green tea extract. The method utilizes RP HPLC with a phenyl-based stationary phase and gradient elution. Detection is by UV absorbance. The total run time, including column re-equilibration, is 13 min. Single-laboratory validation (SLV) has been performed on the method to determine the repeatability, accuracy, selectivity, LOD, LOQ, ruggedness, and linearity for (+)-catechin, (-)-epicatechin, (-)-epicatechin gallate, (-)-epigallocatechin, (-)-gallocatechin gallate, (-)-epigallocatechin gallate, and (+)-gallocatechin, as well as caffeine. Repeatability precision and recovery results met AOAC guidelines for SLV studies for all catechins and caffeine down to a level of approximately 20 mg/g. Finished products containing high concentrations of minerals require the use of EDTA to prevent decomposition of the catechins.

  4. Biophysical Approach to Mechanisms of Cancer Prevention and Treatment with Green Tea Catechins

    OpenAIRE

    Masami Suganuma; Atsushi Takahashi; Tatsuro Watanabe; Keisuke Iida; Takahisa Matsuzaki; Hiroshi Y. Yoshikawa; Hirota Fujiki

    2016-01-01

    Green tea catechin and green tea extract are now recognized as non-toxic cancer preventives for humans. We first review our brief historical development of green tea cancer prevention. Based on exciting evidence that green tea catechin, (−)-epigallocatechin gallate (EGCG) in drinking water inhibited lung metastasis of B16 melanoma cells, we and other researchers have studied the inhibitory mechanisms of metastasis with green tea catechins using biomechanical tools, atomic force microscopy (AF...

  5. Green tea catechins for well-being and therapy: prospects and opportunities

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    Miyoshi N

    2015-12-01

    Full Text Available Noriyuki Miyoshi,1 Monira Pervin,1 Takuji Suzuki,2 Keiko Unno,3 Mamoru Isemura,1 Yoriyuki Nakamura1 1School of Food and Nutritional Sciences, University of Shizuoka, Yada, Shizuoka, Japan; 2Faculty of Education, Art and Science, Yamagata University, Yamagata, Japan; 3School of Pharmaceutical Sciences, University of Shizuoka, Yada, Shizuoka, Japan Abstract: Tea is derived from the leaves and buds of Camellia sinensis (Theaceae plant, and is consumed worldwide. Green tea was discovered in the People's Republic of China approximately 3,000 BC. Lu Yu (733–803 published a book that describes the history of tea, the techniques, and utensils used for manufacturing, the method of preparation, and drinking of tea in the People's Republic of China. Green tea contains various components with specific health-promoting effects and is believed to exert protective effects against diseases such as cancer, obesity, diabetes, hepatitis, and neurodegenerative diseases. Of the various tea components, the polyphenol catechins have been the subject of extensive investigation. Among the catechins, (--epigallocatechin gallate has the strongest bioactivity in most cases. Caffeine induces alertness, decreases the sensation of fatigue, and has a diuretic effect. Theanine and -aminobutyric acid can lower the blood pressure and regulate brain function. Vitamin C exhibits antiscorbutic activity, prevents cataracts, and may boost the immune system. Majority of the scientific evidence based on cellular and animal experiments as well as a number of human epidemiological and intervention studies indicate that green tea and (--epigallocatechin gallate have beneficial health effects against various diseases. However, conflicting results have also been reported. Since confounding factors could affect the results, future studies should be designed to eliminate such factors for better understanding of the benefits of green tea on human health. Genetic and environmental factors

  6. Anti-stress Effect of Green Tea with Lowered Caffeine on Humans: A Pilot Study.

    Science.gov (United States)

    Unno, Keiko; Yamada, Hiroshi; Iguchi, Kazuaki; Ishida, Hitoshi; Iwao, Yasunori; Morita, Akio; Nakamura, Yoriyuki

    2017-01-01

    Theanine, an amino acid in tea, has significant anti-stress effects on animals and humans. However, the effect of theanine was blocked by caffeine and gallate-type catechins, which are the main components in tea. We examined the anti-stress effect of green tea with lowered caffeine, low-caffeine green tea, on humans. The study design was a single-blind group comparison and participants (n=20) were randomly assigned to low-caffeine or placebo tea groups. These teas (≥500 mL/d), which were eluted with room temperature water, were taken from 1 week prior to pharmacy practice and continued for 10 d in the practice period. The participants ingested theanine (ca. 15 mg/d) in low-caffeine green tea. To assess the anxiety of participants, the state-trait anxiety inventory test was used before pharmacy practice. The subjective stress of students was significantly lower in the low-caffeine-group than in the placebo-group during pharmacy practice. The level of salivary α-amylase activity, a stress marker, increased significantly after daily pharmacy practice in the placebo-group but not in the low-caffeine-group. These results suggested that the ingestion of low-caffeine green tea suppressed the excessive stress response of students. This study was registered at the University Hospital Medical Information Network (ID No. UMIN14942).

  7. The protective activity of tea catechins against experimental infection by Vibrio cholerae O1.

    Science.gov (United States)

    Toda, M; Okubo, S; Ikigai, H; Suzuki, T; Suzuki, Y; Hara, Y; Shimamura, T

    1992-01-01

    Tea catechins inhibited the fluid accumulation induced by cholera toxin in sealed adult mice. The catechins also reduced fluid accumulation by Vibrio cholerae O1 in ligated intestinal loops of rabbits. These findings suggest that tea catechins may possess protective activity against V. cholerae O1.

  8. Simple thin layer chromatography (TLC) methods for the separation of catechins from fresh tea leaves

    International Nuclear Information System (INIS)

    Wanyoko, J.K.; Munavu, R.M.

    1985-01-01

    Techniques for separating seven catechins on two adsorbents on thin layer chromatography(TLC) layers were investigated. One of the TLC methods used was fast and gave good resolution of the catechins. Both methods showed that the Rfs of one group of the catechins were related to their structural variations. Thus the methods could be used for the tentative identification of catechins in tea as well as in routine screening of catechins in other plants. (author)

  9. Catechins and Caffeine Inhibit Fat Accumulation in Mice through the Improvement of Hepatic Lipid Metabolism

    Directory of Open Access Journals (Sweden)

    Chikako Sugiura

    2012-01-01

    Full Text Available To elucidate the inhibiting mechanisms of fat accumulation by catechins, caffeine, and epigallocatechin gallate (EGCG, ICR mice were fed diets containing either 0.3% catechins or 0.1% EGCG and/or 0.05% caffeine for 4 weeks. After the feeding, intraperitoneal adipose tissues weights were significantly lower in the caffeine, catechins + caffeine, and EGCG + caffeine groups compared to controls. Hepatic fatty acid synthase (FAS activity in the catechins + caffeine group was significantly lower, and the activities of acyl-CoA oxidase (ACO and carnitine palmitoyltransferase-II (CPT-II were significantly higher, compared to the control group. However, these activities were not observed in the other groups. FAS mRNA expression levels in the catechins + caffeine group were significantly lower than in the control group. ACO and CPT-II mRNA levels were not different among all of the treatment groups. These findings indicate that the inhibitory effects of fat accumulation via a combination of catechins, EGCG, or caffeine were stronger collectively than by either catechins, EGCG, or caffeine alone. Moreover, it was demonstrated that the combination of catechins and caffeine induced inhibition of fat accumulation by suppression of fatty acid synthesis and upregulation of the enzymatic activities involved in β-oxidation of fatty acid in the liver, but this result was not observed by combination of EGCG and caffeine.

  10. Caffeine in teas: levels, transference to infusion and estimated intake

    OpenAIRE

    TFOUNI, Silvia Amelia Verdiani; CAMARA, Maíra Marcuci; KAMIKATA, Kamille; GOMES, Fernanda Moralez Leme; FURLANI, Regina Prado Zanes

    2018-01-01

    Abstract Caffeine is naturally present in several foods, being one of the most consumed dietary ingredients in the world; however, excessive intake may cause health concerns. This study evaluated caffeine levels in teas and their infusions, the transference rate during brewing, and estimated caffeine intake from tea infusion. Brands and batches of 4 types of teas were analyzed for caffeine content by high performance liquid chromatography with a diode array detector. Mate tea was the one that...

  11. Effect of Catechins, Green tea Extract and Methylxanthines in Combination with Gentamicin Against Staphylococcus aureus and Pseudomonas aeruginosa - Combination therapy against resistant bacteria -

    Directory of Open Access Journals (Sweden)

    Bibi Sedigheh Fazly Bazzaz

    2016-12-01

    Full Text Available Objectives: Bacterial resistant infections have become a global health challenge and threaten the society’s health. Thus, an urgent need exists to find ways to combat resistant pathogens. One promising approach to overcoming bacterial resistance is the use of herbal products. Green tea catechins, the major green tea polyphenols, show antimicrobial activity against resistant pathogens. The present study aimed to investigate the effect of catechins, green tea extract, and methylxanthines in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus (S. aureus and the standard strain of Pseudomonas aeruginosa (P. aeruginosa. Methods: The minimum inhibitory concentration (MIC and the minimum bactericidal concentration (MBC values of different agents against bacterial strains were determined. The interactions of green tea extract, epigallate catechin, epigallocatechin gallate, two types of methylxanthine, caffeine, and theophylline with gentamicin were studied in vitro by using a checkerboard method and calculating the fraction inhibitory concentration index (FICI. Results: The MICs of gentamicin against bacterial strains were in the range of 0.312 - 320 μg/mL. The MIC values of both types of catechins were 62.5 - 250 μg/ mL. Green tea extract showed insufficient antibacterial activity when used alone. Methylxanthines had no intrinsic inhibitory activity against any of the bacterial strains tested. When green tea extract and catechins were combined with gentamicin, the MIC values of gentamicin against the standard strains and a clinical isolate were reduced, and synergistic activities were observed (FICI < 1. A combination of caffeine with gentamicin did not alter the MIC values of gentamicin. Conclusion: The results of the present study revealed that green tea extract and catechins potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and standard P. aeruginosa strains

  12. Novel acetylcholinesterase inhibitors from Zijuan tea and biosynthetic pathway of caffeoylated catechin in tea plant.

    Science.gov (United States)

    Wang, Wei; Fu, Xi-Wen; Dai, Xin-Long; Hua, Fang; Chu, Gang-Xiu; Chu, Ming-Jie; Hu, Feng-Lin; Ling, Tie-Jun; Gao, Li-Ping; Xie, Zhong-Wen; Wan, Xiao-Chun; Bao, Guan-Hu

    2017-12-15

    Zijuan tea is a special cultivar of Yunnan broad-leaf tea (Camellia sinensis var. assamica) with purple buds, leaves, and stems. Phytochemical study on this tea led to the discovery of three hydroxycinnamoylated catechins (HCCs) (1-3), seven other catechins (4-10), three proanthocyanidins (11-13), five flavones and flavone glycosides (14-18), two alkaloids (19, 20), one steroid (21), and one phenylpropanoid glycoside (22). The isolation and structural elucidation of the caffeoylated catechin (1) by means of spectroscopic techniques were described. We also provide the first evidence that 1 is synthesized via a two-step pathway in tea plant. The three HCCs (1-3) were investigated on their bioactivity through molecular modeling simulation and biochemical experiments. Our results show that they bind acetylcholinesterase (AChE) tightly and have strong AChE inhibitory activity with IC 50 value at 2.49, 11.41, 62.26μM, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Comparison of Catechins and Antioxidant Activity in Four kinds of Sichuan tea

    Science.gov (United States)

    Li, Jianhua; Chen, Shengxiang; Zhu, Mingzhu; Meng, Xueli

    2017-11-01

    Absract:Catechins of the nine representative teas produced in Sichuan, which belonged to green tea, yellow tea, dark tea and black tea, were determined by UHPLC. Their antioxidant activity was determined by the hydroxyl radical scavenging. The results showed that: the total amount of their catechins was between 0.45(Qingzhuan) ˜ 121.21 mg/g (Mengding ganlu), and the order for theirs was green tea > yellow tea > dark tea (black tea); except Qingzhuan, their EGCG contents were between 1.07 ± 0.01 (Chuanhong gongfu) ˜ 76.16 ±0.43 mg/g (Mengding ganlu), and the order for theirs was green tea > yellow tea> dark tea (black tea); EGCG3“Me, which only remained in green and yellow tea, their contents were between 0.05±0.02 (Mengding Huangya) ˜ 0.39±0.04 mg/g (Mengding ganlu); their hydroxyl radical scavenging was between 48.37±0.20 (Fuzhuan) ˜75.51±0.63% (Mengding Huangya) and their IC50 was between 3.31±0.028 ˜5.18±0.012 mg/mL, the order for their clear rates was yellow tea> green tea> dark tea (black tea). Mengding Huangya showed the highest antioxidant activity in sichuan tea.

  14. Biophysical Approach to Mechanisms of Cancer Prevention and Treatment with Green Tea Catechins.

    Science.gov (United States)

    Suganuma, Masami; Takahashi, Atsushi; Watanabe, Tatsuro; Iida, Keisuke; Matsuzaki, Takahisa; Yoshikawa, Hiroshi Y; Fujiki, Hirota

    2016-11-18

    Green tea catechin and green tea extract are now recognized as non-toxic cancer preventives for humans. We first review our brief historical development of green tea cancer prevention. Based on exciting evidence that green tea catechin, (-)-epigallocatechin gallate (EGCG) in drinking water inhibited lung metastasis of B16 melanoma cells, we and other researchers have studied the inhibitory mechanisms of metastasis with green tea catechins using biomechanical tools, atomic force microscopy (AFM) and microfluidic optical stretcher. Specifically, determination of biophysical properties of cancer cells, low cell stiffness, and high deformability in relation to migration, along with biophysical effects, were studied by treatment with green tea catechins. The study with AFM revealed that low average values of Young's moduli, indicating low cell stiffness, are closely associated with strong potential of cell migration and metastasis for various cancer cells. It is important to note that treatments with EGCG and green tea extract elevated the average values of Young's moduli resulting in increased stiffness (large elasticity) of melanomas and various cancer cells. We discuss here the biophysical basis of multifunctions of green tea catechins and green tea extract leading to beneficial effects for cancer prevention and treatment.

  15. Biophysical Approach to Mechanisms of Cancer Prevention and Treatment with Green Tea Catechins

    Directory of Open Access Journals (Sweden)

    Masami Suganuma

    2016-11-01

    Full Text Available Green tea catechin and green tea extract are now recognized as non-toxic cancer preventives for humans. We first review our brief historical development of green tea cancer prevention. Based on exciting evidence that green tea catechin, (−-epigallocatechin gallate (EGCG in drinking water inhibited lung metastasis of B16 melanoma cells, we and other researchers have studied the inhibitory mechanisms of metastasis with green tea catechins using biomechanical tools, atomic force microscopy (AFM and microfluidic optical stretcher. Specifically, determination of biophysical properties of cancer cells, low cell stiffness, and high deformability in relation to migration, along with biophysical effects, were studied by treatment with green tea catechins. The study with AFM revealed that low average values of Young’s moduli, indicating low cell stiffness, are closely associated with strong potential of cell migration and metastasis for various cancer cells. It is important to note that treatments with EGCG and green tea extract elevated the average values of Young’s moduli resulting in increased stiffness (large elasticity of melanomas and various cancer cells. We discuss here the biophysical basis of multifunctions of green tea catechins and green tea extract leading to beneficial effects for cancer prevention and treatment.

  16. A method for fast determination of epigallocatechin gallate (EGCG, epicatechin (EC, catechin (C and caffeine (CAF in green tea using HPLC Método rápido para determinação de galato de epigalocatequina (EGCG, epicatequina (EC, catequina (C e cafeína (CAF em chá verde usando CLAE

    Directory of Open Access Journals (Sweden)

    Samuel T. Saito

    2006-06-01

    Full Text Available Tea has been considered a medicine and a healthy beverage since ancient times, but recently it has received a great deal of attention because of its antioxidant properties. Green tea polyphenols have demonstrated to be an effective chemopreventive agent. Recently, investigators have found that EGCG, one of the green tea catechins, could have anti-HIV effects when bound to CD4 receptor. Many factors can constitute important influences on the composition of tea, such as species, season, age of the leaf, climate, and horticultural practices (soil, water, minerals, fertilizers. This paper presents an HPLC analytical methodology development, using column RP-18 and mobile phase composed by water, acetonitrile, methanol, ethyl acetate, glacial acetic acid (89:6:1:3:1 v/v/v/v/v for simultaneous determination and quantification of caffeine (CAF, catechin (C, epicatechin (EC and epigallocatechin gallate (EGCG in samples of Camellia sinensis (green tea grown in Brazil and harvested in spring, in summer and in autumn, in comparison to Brazilian black tea, to samples of Japanese and Chinese green tea and to two standardized dry extracts of green tea. The method has been statistically evaluated and has proved to be adequate to qualitative and quantitative determination of the samples.O chá vem sendo considerado uma bebida saudável e com propriedades medicinais desde tempos bem remotos, mas recentemente tem ganhado grande interesse no meio científico devido a suas atividades como antioxidante. Os polifenóis do chá verde vêm demonstrando possuir atividades quimiopreventivas. Recentemente, pesquisadores descobriram que o EGCG, a principal catequina do chá verde, poderia ter efeito anti-HIV quando acoplado ao receptor CD4. Muitos fatores podem influenciar de forma significativa na composição do chá, como sua espécie, estação que foi colhida, idade da folha, clima e técnicas de cultura (solo, irrigação e fertilizantes. Este artigo vem apresentar

  17. Green tea catechins and their metabolites in human skin before and after exposure to ultraviolet radiation.

    Science.gov (United States)

    Clarke, Kayleigh A; Dew, Tristan P; Watson, Rachel E B; Farrar, Mark D; Osman, Joanne E; Nicolaou, Anna; Rhodes, Lesley E; Williamson, Gary

    2016-01-01

    Dietary flavonoids may protect against sunburn inflammation in skin. Preliminary reports using less complete analysis suggest that certain catechins and their metabolites are found in skin biopsies and blister fluid after consumption of green tea; however, it is not known if they are affected by solar-simulated ultraviolet radiation (UVR) or whether conjugated forms, with consequently altered bioactivity, are present. The present study tested the hypothesis that UVR affects the catechin levels in the skin of healthy volunteers after consumption of green tea and how catechins in the plasma are related to their presence in skin tissue samples. In an open oral intervention study, 11 subjects consumed green tea and vitamin C supplements daily for 3months. Presupplementation and postsupplementation plasma samples, suction blister fluid and skin biopsies were collected; the latter two samples were collected both before and after UVR. A sensitive high-performance liquid chromatography/mass spectrometric assay was used to measure the intact catechin metabolites, conjugates and free forms. Seven green tea catechins and their corresponding metabolites were identified postsupplementation in skin biopsies, 20 in blister fluid and 26 in plasma, with 15 green tea catechin metabolites present in both blister fluid and plasma. The valerolactone, O-methyl-M4-O-sulfate, a gut microbiota metabolite of catechins, was significantly increased 1.6-fold by UVR in blister fluid samples. In conclusion, there were some common catechin metabolites in the plasma and blister fluid, and the concentration was always higher in plasma. The results suggest that green tea catechins and metabolites are bioavailable in skin and provide a novel link between catechin metabolites derived from the skin and gut microbiota. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Protecting effect on gamma-ray damage of DNA by tea catechin

    International Nuclear Information System (INIS)

    Yoshioka, H.; Akai, G.; Yoshinaga, K.; Hasegawa, K.; Yoshioka, H.

    1995-01-01

    The protecting effect of the tea catechin on the radiation induced scission of DNA in vitro. was examined. In addition, ESR spin-trapping method was used to make clear the mechanism of the protection. (author)

  19. The Galloyl Catechins Contributing to Main Antioxidant Capacity of Tea Made from Camellia sinensis in China

    Directory of Open Access Journals (Sweden)

    Chunjian Zhao

    2014-01-01

    Full Text Available Total polyphenol content, catechins content, and antioxidant capacities of green, dark, oolong, and black teas made from Camellia sinensis in China were evaluated. The total polyphenol content of 20 samples of tea was in the range of 7.82–32.36%. Total catechins content was in the range of 4.34–24.27%. The antioxidant capacity of tea extract was determined by the oxygen radical absorbance capacity (ORAC test and the 1,1-diphenyl-2-picrylhydrazyl (DPPH radical-scavenging test. Total polyphenol content, catechins content, and antioxidant capacity decreased in the following order: green > oolong > black > dark tea. A positive correlation existed between the antioxidant capacity and total polyphenol content or catechins content (R2=0.67–0.87. The antioxidant capacities of five major catechins (epigallocatechin gallate (EGCG, epicatechin gallate (ECG, epicatechin, epigallocatechin, and catechin were determined by online HPLC DPPH radical-scavenging; the antioxidant activity of tea was mainly attributed to the esterified catechins (EGCG or ECG.

  20. Green Tea Catechin-Inactivated Viral Vaccine Platform

    Directory of Open Access Journals (Sweden)

    Yun H. Lee

    2017-12-01

    Full Text Available Traditionally, chemical agents such as formalin (FA and β-propiolactone (BPL have long been used for the preparation of inactivated vaccines or toxoids. It has been shown that FA extensively modifies vaccine antigens and thus affects immunogenicity profiles, sometimes compromising the protective efficacy of the vaccines or even exacerbating the disease upon infection. In this study, we show that natural catechins from green tea extracts (GT can be used as an inactivating agent to prepare inactivated viral vaccines. GT treatment resulted in complete and irreversible inactivation of influenza virus as well as dengue virus. In contrast to FA that reacted extensively with multiple amino acids including lysine, a major anchor residue for epitope binding to MHC molecules, GT catechin epigallocatechin-3-gallate (EGCG crosslinked primarily with cysteine residues and thus preserved the major epitopes of the influenza hemagglutinin. In a mouse model, vaccination with GT-inactivated influenza virus (GTi virus elicited higher levels of viral neutralizing antibodies than FA-inactivated virus (FAi virus. The vaccination completely protected the mice from a lethal challenge and restricted the challenge viral replication in the lungs. Of note, the quality of antibody responses of GTi virus was superior to that with FAi virus, in terms of the magnitude of antibody titer, cross-reactivity to hetero-subtypes of influenza viruses, and the avidity to viral antigens. As the first report of using non-toxic natural compounds for the preparation of inactivated viral vaccines, the present results could be translated into a clinically relevant vaccine platform with improved efficacy, safety, productivity, and public acceptance.

  1. Metabolic effects of spices, teas, and caffeine.

    Science.gov (United States)

    Westerterp-Plantenga, Margriet; Diepvens, Kristel; Joosen, Annemiek M C P; Bérubé-Parent, Sonia; Tremblay, Angelo

    2006-08-30

    Consumption of spiced foods or herbal drinks leads to greater thermogenesis and in some cases to greater satiety. In this regard, capsaicin, black pepper, ginger, mixed spices, green tea, black tea and caffeine are relevant examples. These functional ingredients have the potential to produce significant effects on metabolic targets such as satiety, thermogenesis, and fat oxidation. A significant clinical outcome sometimes may appear straightforwardly but also depends too strongly on full compliance of subjects. Nevertheless, thermogenic ingredients may be considered as functional agents that could help in preventing a positive energy balance and obesity.

  2. Caffeine in teas: levels, transference to infusion and estimated intake

    Directory of Open Access Journals (Sweden)

    Silvia Amelia Verdiani TFOUNI

    2018-01-01

    Full Text Available Abstract Caffeine is naturally present in several foods, being one of the most consumed dietary ingredients in the world; however, excessive intake may cause health concerns. This study evaluated caffeine levels in teas and their infusions, the transference rate during brewing, and estimated caffeine intake from tea infusion. Brands and batches of 4 types of teas were analyzed for caffeine content by high performance liquid chromatography with a diode array detector. Mate tea was the one that presented lowest levels (6.1 to 13.2 mg/g while Camellia sinensis teas were from 14.3 to 34.8 mg/g. There were statistical differences between different types, brands and batches. Caffeine levels in infusions followed the same pattern of the leaves, with mate tea presenting lowest levels. Caffeine percentage of transference from leaves to infusion varied from 51.5 to 85.2%. Caffeine intake was estimated to be up to 191.4 mg/day. Tea may be considered an important source of caffeine intake for heavy tea drinkers.

  3. Oligomerization and hydroxylation of green tea catechins by oxidative enzymes

    NARCIS (Netherlands)

    Verloop, J.W.

    2016-01-01

    Black teas are known for their characteristic brown colour, bitter taste and astringent mouth feel. These sensory characteristics are mainly influenced by the phenolic oxidation products present in black tea. The oxidation of phenolics from green tea leaves during black tea manufacturing is an

  4. Oligomerization and hydroxylation of green tea catechins by oxidative enzymes

    NARCIS (Netherlands)

    Verloop, J.W.

    2016-01-01

    Black teas are known for their characteristic brown colour, bitter taste and astringent mouth feel. These sensory characteristics are mainly influenced by the phenolic oxidation products present in black tea. The oxidation of phenolics from green tea leaves during black tea manufacturing is an

  5. Daily ingestion of green tea catechins from adulthood suppressed brain dysfunction in aged mice.

    Science.gov (United States)

    Unno, Keiko; Ishikawa, Yuichi; Takabayashi, Fumiyo; Sasaki, Toru; Takamori, Nina; Iguchi, Kazuaki; Hoshino, Minoru

    2008-01-01

    Oxidative damage is believed to be an important cause of senescence. We have previously found that green tea catechins (GT-catechin), potent antioxidants, decrease oxidative damage to DNA and suppress brain dysfunction in aged senescence-accelerated mice (SAMP10) when ingested from the age of 1 month to the age of 12 months. To clarify the effect of GT-catechin on suppression of brain senescence, we investigated the effect of starting period to ingest GT-catechin. Six- or 9-month-old SAMP10 mice were allowed free access to water containing 0.02% GT-catechin. SAMP10 mice exhibit senescence characteristics such as shortened life span, atrophied forebrain and lowered learning and memory abilities. Learning ability was significantly higher in mice that ingested GT-catechin from the age of 6 months to 12 months when compared with same-aged control mice drank water without GT-catechin. Starting GT-catechin intake from the age of 9 months tended to improve learning ability. The ages of 6 and 9 months are thought to be adult and middle ages, respectively in SAMP10 mice. This result suggested that GT-catechin was helpful in suppressing brain dysfunction with aging even when ingestion started at the adult age.

  6. CATECHIN CONTENT AND ANTIOXIDANT ACTIVITY OF SOME BREWED TEMPERATURE OF BLACK TEA SYRUP

    Directory of Open Access Journals (Sweden)

    Tuty Anggraini

    2011-12-01

    Full Text Available The catechin contents and the antioxidant activity of black tea syrup that brewed at some temperature still poorly understood. It has been investigated whether catechin contents and antioxidant activity of black tea syrup may be affected by hot or cold water.  The temperature of 30°C, 60°C, and 90°C were used to brew the syrup, and then the catechin and the antioxidant were determined at each temperature by using DPPH radical scavenging activity method. Measurement of DPPH was conducted for 2 minutes reaction time. Catechin contents were determined by using HPLC method. The result of research showed that the catechin and the antioxidant activity affected by temperature tested. Five kinds of catechin derivatives detected in black tea syrup, EGC (epigallocatechin, C (catechin, EGCG (epigallocatechin gallate, EC (epicatechin and ECG (epicatechin gallate. The highest DPPH scavenging activity of black tea syrup was showed by 30°C.ABSTRAKKandungan katechin dan aktivitas antioksidan dari sirup teh hitam yang diseduh pada beberapa temperatur masih belum begitu dipahami. Pada penelitian ini telah diselidiki apakan kandungan katechin dan aktioksidan dipengaruhi oleh air dingin atau air panas. Temperatur 30oC, 60oC, dan 90oC digunakan untuk menyeduh sirup teh hitam lalu ditentukan kandungan katechin dan aktifitas antioksidannya pada masing-masing temperatur menggunakan metode aktifitas perangkap radikal bebas DPPH (dyphenyl pycrylhydrazyl. Pengukuran DPPH dilakukan selama waktu reaksi dua menit. Kandungan katechin ditentukan menggunakan metode HPLC (High Performance Liquid Chromatography. Hasil penelitian menunjukkan bahwa kandungan katechin dan aktifitas antioksidan sirup teh hitam dipengaruhi oleh temperatur yang diuji. Lima jenis turunan katechin terdeteksi dalam sirup teh hitam yaitu EGC (epigallocatechin, C (catechin, EGCG (epigallocatechin gallate, EC (epicatechin and ECG (epicatechin gallate. Aktifitas perangkap DPPH tertinggi dari sirup teh

  7. Green tea catechins reduced the glycaemic potential of bread: an in vitro digestibility study.

    Science.gov (United States)

    Goh, Royston; Gao, Jing; Ananingsih, Victoria K; Ranawana, Viren; Henry, Christiani Jeyakumar; Zhou, Weibiao

    2015-08-01

    Green tea catechins are potent inhibitors of enzymes for carbohydrate digestion. However, the potential of developing low glycaemic index bakery food using green tea extract has not been investigated. Results of this study showed that addition of green tea extract (GTE) at 0.45%, 1%, and 2% concentration levels significantly reduced the glycaemic potential of baked and steamed bread. The average retention levels of catechins in the baked and steamed bread were 75.3-89.5% and 81.4-99.3%, respectively. Bread fortified with 2% GTE showed a significantly lower level of glucose release during the first 90 min of pancreatic digestion as well as a lower content of rapidly digested starch (RDS) content. A significantly negative correlation was found between the catechin retention level and the RDS content of bread. The potential of transforming bread into a low GI food using GTE fortification was proven to be promising. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Potential role of green tea catechins in the management of oxidative stress-associated infertility.

    Science.gov (United States)

    Roychoudhury, Shubhadeep; Agarwal, Ashok; Virk, Gurpriya; Cho, Chak-Lam

    2017-05-01

    Reactive oxygen species (ROS) are present in low concentrations in the genital tracts of males and females. Excessive ROS lead to oxidative stress, which damages DNA, lipids and proteins. Such molecular changes result in compromised vitality, increased morphological defects and decreased sperm motility in the male. In the female, oxidative stress interferes with oocyte maturation, and may inhibit in-vitro maturation of the oocyte. Recently, green tea supplementation has been reported to possess properties that may improve the quality of male and female gametes largely due to the ability of catechin polyphenols to quench ROS. Epigallocatechin-3-gallate (EGCG) is considered the most promising bioactive compound in green tea due to its strong antioxidant activity. The unique property of green tea catechins may potentially improve reproductive health and pose an important research area. We present a comprehensive overview on the effects and potential roles of green tea catechins on oxidative stress in male and female reproduction and fertility. In this review, possible mechanisms of action are highlighted to better understand the potential use of green tea catechins in the reduction of oxidative stress and its associated beneficial effects in the clinical setting. Copyright © 2017 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

  9. Bactericidal activity of green tea extracts: the importance of catechin containing nano particles.

    Science.gov (United States)

    Gopal, Judy; Muthu, Manikandan; Paul, Diby; Kim, Doo-Hwan; Chun, Sechul

    2016-01-28

    When we drink green tea infusion, we believe we are drinking the extract of the green tea leaves. While practically each tea bag infused in 300 mL water contains about 50 mg of suspended green tea leaf particles. What is the role of these particles in the green tea effect is the objective of this study. These particles (three different size ranges) were isolated via varying speed centrifugation and their respective inputs evaluated. Live oral bacterial samples from human volunteers have been screened against green tea extracts and macro, micro and nano sized green tea particles. The results showed that the presence/absence of the macro and mico sized tea particles in the green tea extract did not contribute much. However, the nano sized particles were characterized to be nature's nano stores of the bioactive catechins. Eradication of these nano tea particles resulted in decrease in the bactericidal property of the green tea extracts. This is a curtain raiser investigation, busting the nano as well as green tea leaf particle contribution in green tea extracts.

  10. Inhibition of Catalase by Tea Catechins in Free and Cellular State: A Biophysical Approach

    Science.gov (United States)

    Pal, Sandip; Dey, Subrata Kumar; Saha, Chabita

    2014-01-01

    Tea flavonoids bind to variety of enzymes and inhibit their activities. In the present study, binding and inhibition of catalase activity by catechins with respect to their structure-affinity relationship has been elucidated. Fluorimetrically determined binding constants for (−)-epigallocatechin gallate (EGCG) and (−)-epicatechin gallate (ECG) with catalase were observed to be 2.27×106 M−1 and 1.66×106 M−1, respectively. Thermodynamic parameters evidence exothermic and spontaneous interaction between catechins and catalase. Major forces of interaction are suggested to be through hydrogen bonding along with electrostatic contributions and conformational changes. Distinct loss of α-helical structure of catalase by interaction with EGCG was captured in circular dichroism (CD) spectra. Gallated catechins demonstrated higher binding constants and inhibition efficacy than non-gallated catechins. EGCG exhibited maximum inhibition of pure catalase. It also inhibited cellular catalase in K562 cancer cells with significant increase in cellular ROS and suppression of cell viability (IC50 54.5 µM). These results decipher the molecular mechanism by which tea catechins interact with catalase and highlight the potential of gallated catechin like EGCG as an anticancer drug. EGCG may have other non-specific targets in the cell, but its anticancer property is mainly defined by ROS accumulation due to catalase inhibition. PMID:25025898

  11. Effect of ultraviolet B irradiation on accumulation of catechins in tea ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-09-17

    Sep 17, 2008 ... chins are a group of important sunscreens (Mamati et al., ... lation of catechins in tea plant may lead to development of ... Different influence rates were obtained by regulating the lamp num- ber and distance between the plants and the lamps. The plants were irradiated by UV-B influence rates of 0.2, 0.4, 1.0 ...

  12. Alleviation of UV-B stress in Arabidopsis using tea catechins | Lee ...

    African Journals Online (AJOL)

    Ultraviolet-B (UV-B) has been confirmed to be harmful to living organisms and it is of concern that the amount of UV-B radiation reaching the earth's surface is increasing because of the depletion of the stratospheric ozone layer. Effect of different levels of tea catechins on morphological damage and expression of chalcone ...

  13. Green Tea Catechin Consumption Enhances Exercise-Induced Abdominal Fat Loss

    Science.gov (United States)

    Aim: This study evaluated the influence of a green tea catechin beverage on body composition and fat distribution in overweight and obese adults during exercised-induced weight loss. Methods: Participants (N=132) were randomly assigned to receive a 500 mL beverage containing approximately 625 mg of...

  14. Systemic Absorption of Catechins after Intraruminal or Intraduodenal Application of a Green Tea Extract in Cows

    Science.gov (United States)

    Wein, Silvia; Beyer, Birgit; Gohlke, Annika; Blank, Ralf; Metges, Cornelia C.; Wolffram, Siegfried

    2016-01-01

    Green tea catechins have various potential health benefits in humans including anti-inflammatory, anti-oxidative and hepato-protective effects. If present in the circulation, they might have similar effects in ruminants, which are exposed to oxidative stress and fatty liver disease such as dairy cows during the periparturient phase. However, the bioavailability of a substance is a prerequisite for any post absorptive effect in vivo. This study aimed to investigate the appearance of catechins from a green tea extract (GTE) in cattle plasma after intraruminal and intraduodenal administration because absorption is of major importance regarding the bioavailability of catechins. The studies were performed in 5 rumen-fistulated non-lactating heifers and 6 duodenally fistulated lactating dairy cows, respectively, equipped with indwelling catheters placed in a jugular vein. The GTE was applied intraruminally (10 and 50 mg/kg BW, heifers) or duodenally (10, 20 and 30 mg/kg BW, dairy cows) in a cross‐over design with a 2 d washout period between different dosages. Blood samples were drawn following the GTE administration at various pre-defined time intervals. The concentration of the major GTE catechins (gallocatechin, epigallocatechin, catechin, epicatechin, epigallocatechin-gallate, epicatechin-gallate) in plasma samples were analysed by HPLC with electrochemical detection. Irrespective of the dose, almost none of the catechins originally contained in the GTE were detected in plasma samples after intraruminal application. In contrast, intraduodenal administration of GTE resulted in increased plasma concentrations of epicatechin, epigallocatechin, epigallocatechin gallate in a dose‐dependent manner. Thus, we can conclude that intraruminally or orally administered catechins are intensively metabolized by ruminal microorganisms. PMID:27427946

  15. Tea and Cancer Prevention: Strengths and Limits of the Evidence

    Science.gov (United States)

    ... from dried leaves and buds (either in tea bags or loose), prepared from dry instant tea mixes, ... presentation of catechin and caffeine information, and some values reported on product labels were inconsistent with analyzed ...

  16. Catechin content and the degree of its galloylation in oolong tea are inversely correlated with cultivation altitude

    Directory of Open Access Journals (Sweden)

    Guan-Heng Chen

    2014-09-01

    Full Text Available The taste quality of oolong tea generated from leaves of Camellia sinensis L. cultivated in the same mountain area is positively correlated to the cultivation altitude, partly due to the inverse correlation with the astringency of the tea infusion. The astringency of oolong tea mostly results from the presence of polyphenolic compounds, mainly catechins and their derivatives. Four catechins, (--epicatechin (EC and (--epigallocatechin (EGC together with their gallate derivatives (with relatively high astringency, (--EC gallate (ECG and (--EGC gallate (EGCG, were detected as major compounds in oolong tea. The degrees of catechin galloylation, designated as ECG/(EC + ECG and EGCG/(EGC + EGCG, in both oolong tea infusions and their fresh tea leaves, were found to be inversely correlated to the cultivation altitude at 200 m, 800 m, and 1300 m. A similar inverse correlation was observed when seven more oolong tea infusions and seven more fresh leaves harvested at altitude ranging from 170 m to 1600 m were recruited for the analyses. Moreover, catechin contents in oolong tea infusions were also found to be inversely correlated to the cultivation altitude. It is proposed that catechin content and the degree of its galloylation account for, at least partly, the inverse correlation between the astringency of oolong tea and the cultivation altitude.

  17. Inhibiting effect of tea catechins on the lipid peroxidation induced in tritiated water

    Energy Technology Data Exchange (ETDEWEB)

    Kubota, M. [Radiochemical Research Laboratory, University of Shizuoka, 836 Ohya, Shizuoka-shi 422-8529 (Japan); Takeuchi, Y. [Radiochemical Research Laboratory, University of Shizuoka, 836 Ohya, Shizuoka-shi 422-8529 (Japan); Okuno, K. [Radiochemical Research Laboratory, University of Shizuoka, 836 Ohya, Shizuoka-shi 422-8529 (Japan); Yoshioka, H. [Institute for Environmental Sciences, University of Shizuoka, 52-1 Yada, Shizuoka-shi 422-8526 (Japan); Yoshioka, H. [Radiochemical Research Laboratory, University of Shizuoka, 836 Ohya, Shizuoka-shi 422-8529 (Japan)]. E-mail: srhyosi@ipc.shizuoka.ac.jp

    2006-02-15

    Lipid peroxidation induced by {beta}-ray in tritiated water and the inhibiting effect of tea catechins on it were studied using a spin probe method. A hydrophobic spin probe, 16-doxylstearic acid (16NS), was incorporated into a liposome prepared from egg yolk phosphatidylcholine, which was dispersed in tritiated water; the catechins were added to the solution. The rate of the decrease of ESR intensity of 16NS was a measure of the peroxidation and of the inhibiting effect. Inhibiting activity increased with an increase in the concentration of the catechin. Inhibiting ability estimated from the slope of the curves was in the order of (-)-epicatechin gallate > (-)-epigallocatechin gallate > (-)-epicatechin > (-)-epigallocatechin. The activity decreased with increasing temperature and the temperature dependence increased with the catechin concentration. These results were explained by a model; the initiator of the peroxidation is the hydroxyl radical (OH) and catechin is adsorbed on the surface of the membrane and scavenges OH coming into there from the water phase. The activity depended on the ratio of the adsorbed catechin, namely the partition coefficient between the water and the lipid.

  18. [Antibacterial and anti-hemolysin activities of tea catechins and their structural relatives].

    Science.gov (United States)

    Toda, M; Okubo, S; Ikigai, H; Shimamura, T

    1990-03-01

    Among catechins tested, (-)epigallocatechin (EGC), (-)epicatechin gallate (ECg), (-) epigallocatechin gallate (EGCg) inhibited the growth of Staphylococcus aureus, Vibrio cholerae O1 classical Inaba 569B and El Tor Inaba V86. S. aureus was more sensitive than V. cholerae O1 to these compounds. EGCg showed also a bactericidal activity against V. cholerae O1 569B. Pyrogallol showed a stronger antibacterial activity against S. aureus and V. cholerae O1 than tannic and gallic acid. Rutin or caffein had no effect on them. ECg and EGCg showed the most potent anti-hemolysin activity against S. aureus alpha-toxin, Vibrio parahaemolyticus thermostable direct hemolysin (Vp-TDH) and cholera hemolysin. Among catechin relatives, only tannic acid had a potent anti-hemolysin activity against alpha-toxin. These results suggest that the catechol and pyrogallol groups are responsible for the antibacterial and bactericidal activities, while the conformation of catechins might play an important role in the anti-hemolysin activity.

  19. Physiologically based pharmacokinetic modeling of tea catechin mixture in rats and humans.

    Science.gov (United States)

    Law, Francis C P; Yao, Meicun; Bi, Hui-Chang; Lam, Stephen

    2017-06-01

    Although green tea ( Camellia sinensis) (GT) contains a large number of polyphenolic compounds with anti-oxidative and anti-proliferative activities, little is known of the pharmacokinetics and tissue dose of tea catechins (TCs) as a chemical mixture in humans. The objectives of this study were to develop and validate a physiologically based pharmacokinetic (PBPK) model of tea catechin mixture (TCM) in rats and humans, and to predict an integrated or total concentration of TCM in the plasma of humans after consuming GT or Polyphenon E (PE). To this end, a PBPK model of epigallocatechin gallate (EGCg) consisting of 13 first-order, blood flow-limited tissue compartments was first developed in rats. The rat model was scaled up to humans by replacing its physiological parameters, pharmacokinetic parameters and tissue/blood partition coefficients (PCs) with human-specific values. Both rat and human EGCg models were then extrapolated to other TCs by substituting its physicochemical parameters, pharmacokinetic parameters, and PCs with catechin-specific values. Finally, a PBPK model of TCM was constructed by linking three rat (or human) tea catechin models together without including a description for pharmacokinetic interaction between the TCs. The mixture PBPK model accurately predicted the pharmacokinetic behaviors of three individual TCs in the plasma of rats and humans after GT or PE consumption. Model-predicted total TCM concentration in the plasma was linearly related to the dose consumed by humans. The mixture PBPK model is able to translate an external dose of TCM into internal target tissue doses for future safety assessment and dose-response analysis studies in humans. The modeling framework as described in this paper is also applicable to the bioactive chemical in other plant-based health products.

  20. Modulation of signal transduction by tea catechins and related phytochemicals

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Masahito [Herbert Irving Comprehensive Cancer Center and Department of Medicine, Columbia University Medical Center, HHSC-1509, 701 West 168 Street, NY 10032-2704 (United States); Weinstein, I. Bernard [Herbert Irving Comprehensive Cancer Center and Department of Medicine, Columbia University Medical Center, HHSC-1509, 701 West 168 Street, NY 10032-2704 (United States)]. E-mail: ibw1@columbia.edu

    2005-12-11

    Epidemiologic studies in human populations and experimental studies in rodents provide evidence that green tea and its constituents can inhibit both the development and growth of tumors at a variety of tissue sites. In addition, EGCG, a major biologically active component of green tea, inhibits growth and induces apoptosis in a variety of cancer cell lines. The purpose of this paper is to review evidence that these effects are mediated, at least in part, through inhibition of the activity of specific receptor tyrosine kinases (RTKs) and related downstream pathways of signal transduction. We also review evidence indicating that the antitumor effects of the related polyphenolic phytochemicals resveratrol, genistein, curcumin, and capsaicin are exerted via similar mechanisms. Some of these agents (EGCG, genistein, and curcumin) appear to directly target specific RTKs, and all of these compounds cause inhibition of the activity of the transcription factors AP-1 and NF-{kappa}B, thus inhibiting cell proliferation and enhancing apoptosis. Critical areas of future investigation include: (1) identification of the direct molecular target(s) of EGCG and related polyphenolic compounds in cells; (2) the in vivo metabolism and bioavailability of these compounds; (3) the ancillary effects of these compounds on tumor-stromal interactions; (4) the development of synergistic combinations with other antitumor agents to enhance efficacy in cancer prevention and therapy, and also minimize potential toxicities.

  1. Effect of shaking process on correlations between catechins and volatiles in oolong tea

    Directory of Open Access Journals (Sweden)

    Shu-Yen Lin

    2016-07-01

    Full Text Available Shaking the tea leaves is the key manipulation to making oolong tea. It contributes to the formation of flavor and fragrance in oolong tea. The dynamic variations of catechins and volatile organic compounds (VOCs during the shaking process were investigated. The results showed that the contents of epicatechin, epigallocatechin, epicatechin gallate (ECG, and epigallocatechin gallate (EGCG first decreased after the shaking and then increased to the initial value before the next shaking. Geraniol, linalool and its oxides, and phenylethyl alcohol showed similar variations. The contents of trans-β-ocimene, 1H-indole, and 3-hexenyl hexanoate increased after the second or third shaking (the late fermentation stage. However, the contents of aldehydes showed an opposite trend to other VOCs. The abundance of phenylethyl alcohol was positively related to the content of ECG and EGCG ​during fermentation, whereas the abundance of cis-3-hexenal was negatively related to the content of ECG. The correlations between catechin and VOCs indicated that shaking affected the chemical transformation of the compounds in oolong tea.

  2. Elucidation of the Corrosion Inhibition of Mild Steel in 1.0 M HCl by Catechin Monomers from Commercial Green Tea Extracts

    Science.gov (United States)

    Nofrizal, S.; Rahim, Afidah A.; Saad, Bahruddin; Bothi Raja, P.; Shah, Affaizza M.; Yahya, S.

    2012-04-01

    The inhibitive action of commercial green tea extracts on mild steel (MS) in a 1.0 M hydrochloric acid solution was investigated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). A high-performance liquid chromatographic (HPLC) analysis showed conclusively that of the eight catechin monomers and caffeine found in the original extracts, only four components were responsible for the inhibition of MS. The decreasing adsorption capacity of monomers on MS is related to the stereochemistry of molecules and the number of phenolic groups, and it is as follows: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin. Adsorption of green tea extract constituent was found to follow Langmuir adsorption isotherm and the calculated Gibb's free energy values indicated the physisorption of inhibitor over MS surface. Physisorption was supported well by the potential zero charge (PZC) and molecular surface energy-level calculations.

  3. A SIMPLE METHOD FOR DETERMINATION OF CAFFEINE CONTENT IN TEA SAMPLES

    OpenAIRE

    Venkatesh, Sama; Swamy, M.M.; Reddy, Y.S.R.; Suresh, B.; Sethuraman, M.

    1994-01-01

    The present communication describes a simple and modified colorimetric procedure for the estimation of caffeine content in both commercial and locally available tea samples. Comparative data of caffeine content in different brands of tea samples are shown here. The present method is no doubt an improvised procedure for estimating directly caffeine content from the tea extracts. A possible explanation to account for the variability in caffeine content in different samples is offered.

  4. Biotransformation of catechin and extraction of active polysaccharide from green tea leaves via simultaneous treatment with tannase and pectinase.

    Science.gov (United States)

    Baik, Joo Hyun; Shin, Kwang-Soon; Park, Yooheon; Yu, Kwang-Won; Suh, Hyung Joo; Choi, Hyeon-Son

    2015-08-30

    Green tea is a dietary source of bioactive compounds for human health. Enzymatic treatments induce the bioconversion of bioactive components, which can improve biological activities. In this study, we investigated the effect of simultaneous treatment with tannase and Rapidase on biotransformation of catechins and extraction of polysaccharide from green tea extract (GTE). Tannase and pectinase treatments induced the biotransformation of catechins and altered tea polysaccharide () content. The addition of GTE to the enzyme reaction resulted in a significant increase in degallated catechins, including gallic acid, a product of the tannase reaction (314.5-4076.0 µg mL(-1)) and a reduction in epigallocatechin gallate (EGCG). Biotransformation of catechins improved the radical scavenging activity of GTE. Pectinase treatment led to change of TPS composition in GTE by hydrolyzing polysaccharides. In addition, pectinase-driven hydrolysis in polysaccharides significantly increased TPS-induced Interleukin 6 (IL-6) production in macrophages. In particular, treatment of Rapidase (TPS-Ra) led to the highest IL-6 production among TPS samples, similar to treatment of highly purified pectinase (TPS-GTE), a positive control. Simultaneous processing with tannase and Rapidase can be an efficient method for the extraction of bioactive polysaccharides and biotransformation of catechins with enhanced radical scavenging activity from green tea. © 2014 Society of Chemical Industry.

  5. Interaction between Ester-Type Tea Catechins and Neutrophil Gelatinase-Associated Lipocalin: Inhibitory Mechanism.

    Science.gov (United States)

    Zhang, Wei; Li, Xiao; Hua, Fang; Chen, Wei; Wang, Wei; Chu, Gang-Xiu; Bao, Guan-Hu

    2018-02-07

    Tea is thought to alleviate neurotoxicity due to the antioxidative effect of ester-type tea catechins (ETC). Neutrophil gelatinase-associated lipocalin (NGAL) can sensitize β-amyloid (Aβ) induced neurotoxicity, and inhibitors of NGAL may relieve associated symptoms. As such, the interactions of ETC with NGAL were investigated by fluorescence spectrometry and molecular simulation. NGAL fluorescence is quenched regularly when being added with six processing types of tea infusion (SPTT) and ETC. Thermodynamic analyses suggest that ETC with more catechol moieties has a stronger binding capacity with NGAL especially in the presence of Fe 3+ . (-)-Epicatechin 3-O-caffeoate (ECC), a natural product isolated from Zijuan green tea, shows the strongest binding ability with NGAL (K d = 15.21 ± 8.68 nM in the presence of Fe 3+ ). All ETC are effective in protecting nerve cells against H 2 O 2 or Aβ 1-42 induced injury. The inhibitory mechanism of ETC against NGAL supports its potential use in attenuation of neurotoxicity.

  6. The effects of co-administration of butter on the absorption, metabolism and excretion of catechins in rats after oral administration of tea polyphenols.

    Science.gov (United States)

    Zhang, Liang; Han, Yuhui; Xu, Liwei; Liang, Yuhong; Chen, Xin; Li, Junsong; Wan, Xiaochun

    2015-07-01

    In Southwest China, tea polyphenols are usually utilized by way of butter tea. Tea polyphenols inhibit the absorption and biosynthesis of fatty acids in vivo, but the effects of butter on the pharmacokinetics of tea polyphenols have drawn less concern. A rapid UHPLC-MS/MS method was used to quantitatively determine the catechins in the plasma, feces and bile of rats after the oral administration of tea polyphenol or its combination with butter. In comparison with the single tea polyphenol treatment, the maximum plasma concentrations (Cmax) of the free EGCG, EGC, EC, GCG, GC and ECG significantly decreased after the co-administration of butter. The mean residence times (MRT) of the free EGCG, EGC, EC, GC and ECG were also significantly prolonged. When the plasma samples were treated with β-glucuronidase and arylsulfatase, the pharmacokinetic parameters of the total catechins (free and conjugated forms) were not affected by the co-administration of butter. These results indicated that the total absorption of catechins was not affected by butter, but the metabolism of catechins had been changed. Furthermore, the fecal catechins were significantly increased by butter. The total fecal amount and excretion ratio of all catechins were increased highly. The biliary excretion of EGCG, EGC, EC, GCG and GC was significantly increased by the co-administration of butter. To sum up, the butter changed the metabolism of catechins in vivo by decreasing the plasma concentration of the free catechins but increasing the conjugated catechins.

  7. Construction of a SSR-Based Genetic Map and Identification of QTLs for Catechins Content in Tea Plant (Camellia sinensis)

    Science.gov (United States)

    Ma, Chun-Lei; Wang, Xin-Chao; Jin, Ji-Qiang; Wang, Xue-Min; Chen, Liang

    2014-01-01

    Catechins are the most important bioactive compounds in tea, and have been demonstrated to possess a wide variety of pharmacological activities. To characterize quantitative trait loci (QTLs) for catechins content in the tender shoots of tea plant, we constructed a moderately saturated genetic map using 406 simple sequence repeat (SSR) markers, based on a pseudo-testcross population of 183 individuals derived from an intraspecific cross of two Camellia sinensis varieties with diverse catechins composition. The map consisted of fifteen linkage groups (LGs), corresponding to the haploid chromosome number of tea plant (2n = 2x = 30). The total map length was 1,143.5 cM, with an average locus spacing of 2.9 cM. A total of 25 QTLs associated with catechins content were identified over two measurement years. Of these, nine stable QTLs were validated across years, and clustered into four main chromosome regions on LG03, LG11, LG12 and LG15. The population variability explained by each QTL was predominantly at moderate-to-high levels and ranged from 2.4% to 71.0%, with an average of 17.7%. The total number of QTL for each trait varied from four to eight, while the total population variability explained by all QTLs for a trait ranged between 38.4% and 79.7%. This is the first report on the identification of QTL for catechins content in tea plant. The results of this study provide a foundation for further cloning and functional characterization of catechin QTLs for utilization in improvement of tea plant. PMID:24676054

  8. Interaction of Environmental Moisture with Powdered Green Tea Formulations: Relationship between Catechin Stability and Moisture-Induced Phase Transformations

    Science.gov (United States)

    Ortiz, Julieta; Kestur, Umesh S.; Taylor, Lynne S.; Mauer, Lisa J.

    2009-01-01

    This study investigated the effect of phase transformations of amorphous and deliquescent ingredients on catechin stability in green tea powder formulations. Blends of amorphous green tea and crystalline sucrose, citric acid, and/or ascorbic acid were analyzed by X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), dynamic water vapor sorption, water activity measurements, and high-performance liquid chromatography (HPLC) after storage for up to 12 weeks at 0–75% relative humidity (RH) and 22 °C. The glass transition temperature (Tg) of green tea was reduced to below room temperature (moisture sorption. Catechin degradation was affected by Tg of green tea powder and both dissolution and deliquescence of citric and ascorbic acids. PMID:19489621

  9. Theanine and Caffeine Content of Infusions Prepared from Commercial Tea Samples

    OpenAIRE

    Boros, Kl?ra; Jedlinszki, Nikoletta; Csupor, Dezs?

    2016-01-01

    Background: Caffeine and L-theanine are pharmacologically important constituents of tea, especially due to their effects on the central nervous system. The effects of these two compounds are opposite: While caffeine is a well-known stimulant, theanine has a relaxing effect. Tea processing may influence the caffeine and theanine content of tea leaves. Objective: The aim of our work was to quantify these constituents from a set of commercial products to reveal the possible correlations of caffe...

  10. Caffeine in tea Camellia sinensis--content, absorption, benefits and risks of consumption.

    Science.gov (United States)

    Gramza-Michałowska, A

    2014-01-01

    Therapeutic properties of tea Camellia sinensis are of particular interest since it has been consumed for ages and was always regarded as safe beverage. Tea is most popular beverage in the world because of its attractive aroma, exceptional taste, health promoting and pharmaceutical potential. Current results showed that antioxidative, antibacterial and other health effects are attributed to its caffeine content and caffeine - polyphenols interactions. An overview is given on caffeine content in different tea leaves beverage. Special attention is drawn to caffeine physiological effect on human organism. Controversies concerning the possible caffeine influence on human physical and psychological health are briefly summarized and presented.

  11. Green tea catechins quench the fluorescence of bacteria-conjugated Alexa fluor dyes.

    Science.gov (United States)

    Zhao, Lin; Li, Wei; Zhu, Shu; Tsai, Sheena; Li, Jianhua; Tracey, Kevin J; Wang, Ping; Fan, Saijun; Sama, Andrew E; Wang, Haichao

    2013-10-01

    Accumulating evidence suggests that Green tea polyphenolic catechins, especially the (-)-epigallocatechin gallate (EGCG), can be cross-linked to many proteins, and confer a wide range of anti-bacterial activities possibly by damaging microbial cytoplasmic lipids and proteins. At the doses that conferred protection against lethal polymicrobial infection (induced by cecal ligation and puncture), EGCG significantly reduced bacterial loads particularly in the liver and lung. To elucidate its bactericidal mechanisms, we determined whether EGCG affected the fluorescence intensities of bacteria-conjugated Alexa Fluor 488 or 594 dyes. When mixed with unconjugated Alexa Fluor 488 or 594 dyes, EGCG or analogs did not affect the fluorescence intensity of these dyes. In a sharp contrast, EGCG and some analogs (e.g., Catechin Gallate, CG), markedly reduced the fluorescence intensity of Gram-positive Staphylococcus aureus-conjugated Alexa 594 and Gram-negative Escherichia coli-conjugated Alexa 488. Interestingly, co-treatment with ethanol impaired the EGCG-mediated fluorescence quenching of the G(+) S. aureus, but not of the G(-) E. coli-conjugated Alexa Flour dyes. In light of the notion that Alexa Fluor dyes can be quenched by aromatic amino acids, it is plausible that EGCG exerts antimicrobial activities possibly by altering microbial protein conformations and functions. This possibility can now be explored by screening other fluorescence-quenching agents for possible antimicrobial activities.

  12. Determination of catechin in green tea using a catechol oxidase biomimetic sensor

    International Nuclear Information System (INIS)

    Fernandes, Suellen C.; Osorio, Renata El-Hage M. de Barros; Anjos, Ademir dos; Neves, Ademir; Micke, Gustavo Amadeu; Vieira, Iolanda C.

    2008-01-01

    A catechol oxidase biomimetic sensor, based on a novel copper(II) complex, was developed for the determination of catechin in green tea and the results were compared with those obtained by capillary electrophoresis. The dinuclear copper(II) complex, [Cu 2 (HL)(μ-CH 3 COO)](ClO 4 ), containing the ligand N,N-[bis-(2-pyridylmethyl)]-N',N'-[(2-hydroxybenzyl)(2-hydroxy-3,5-di-tert - butylbenzyl)]-1,3-propanediamine-2-ol (H 3 L), was synthesized and characterized by IR, 1 H NMR and elemental analysis. The best conditions for the optimization of the biomimetic sensor were established by square wave voltammetry. The best performance for this sensor was obtained in 75:15:10% (m/m/m) of the graphite powder:nujol:copper(II) complex, 0.05 mol L -1 phosphate buffer solution (pH 7.5) and frequency, pulse amplitude, scan increment at 30 Hz, 80 mV, 3.3 mV, respectively. The analytical curve was linear in the concentration range 4.95 x 10 -6 to 3.27 x 10 -5 mol L -1 (r = 0.9993) with a detection limit of 2.8 x 10 -7 mol L -1 . This biomimetic sensor demonstrated long-term stability (9 months; 800 determinations) and reproducibility with a relative standard deviation of 3.5%. The recovery of catechin from green tea samples ranged from 93.8 to 106.9% and the determination, compared with that obtained using capillary electrophoresis, was found to be acceptable at the 95% confidence level. (author)

  13. Effects of exercise and tea catechins on muscle mass, strength and walking ability in community-dwelling elderly Japanese sarcopenic women: a randomized controlled trial.

    Science.gov (United States)

    Kim, Hunkyung; Suzuki, Takao; Saito, Kyoko; Yoshida, Hideyo; Kojima, Narumi; Kim, Miji; Sudo, Motoki; Yamashiro, Yukari; Tokimitsu, Ichiro

    2013-04-01

    To investigate the effects of exercise and/or tea catechin supplementation on muscle mass, strength and walking ability in elderly Japanese women with sarcopenia. A total of 128 women aged over 75 years were defined as sarcopenic and randomly assigned into four groups: exercise and tea catechin supplementation (n = 32), exercise (n = 32), tea catechin supplementation (n = 32) or health education (n = 32). The exercise group attended a 60-min comprehensive training program twice a week and the tea catechin supplementation group ingested 350 mL of a tea beverage fortified with catechin daily for 3 months. Body composition was determined by bioelectrical impedance analysis. Interview data and functional fitness measurements, such as muscle strength, balance and walking ability, were collected at baseline and after the 3-month intervention. There were significant group × time interactions observed in timed up & go (P exercise + catechin group showed a significant effect (odds ratio 3.61, 95% confidence interval 1.05-13.66) for changes in the combined variables of leg muscle mass and usual walking speed compared with the health education group. The combination of exercise and tea catechin supplementation had a beneficial effect on physical function measured by walking ability and muscle mass. © 2012 Japan Geriatrics Society.

  14. Caffeine

    Science.gov (United States)

    What is caffeine? Caffeine is a bitter substance that occurs naturally in more than 60 plants including Coffee beans Tea leaves Kola nuts, ... chocolate products There is also synthetic (man-made) caffeine, which is added to some medicines, foods, and ...

  15. Comparing the effect of aqueous extract of green tea and catechin on gonadotropins, β-estradiol, Progesterone, testosterone and ovarian follicle in polycystic ovarian syndrome rat model

    Directory of Open Access Journals (Sweden)

    Sayed Damoon Sadoughi

    2017-09-01

    Conclusion: Compared with green tea, catechin has a more favorable effect on improving hormonal parameters, especially FSH hormone and increasing the number of ovarian follicles in rats with polycystic ovary syndrome.

  16. The Powdering Process with a Set of Ceramic Mills for Green Tea Promoted Catechin Extraction and the ROS Inhibition Effect

    Directory of Open Access Journals (Sweden)

    Kouki Fujioka

    2016-04-01

    Full Text Available For serving green tea, there are two prominent methods: steeping the leaf or the powdered leaf (matcha style in hot water. The purpose of the present study was to reveal chemical and functional differences before and after the powdering process of green tea leaf, since powdered green tea may contribute to expanding the functionality because of the different ingesting style. In this study, we revealed that the powdering process with a ceramic mill and stirring in hot water increased the average extracted concentration of epigallocatechin gallate (EGCG by more than three times compared with that in leaf tea using high-performance liquid chromatography (HPLC and liquid chromatography–tandem mass Spectrometry (LC-MS/MS analyses. Moreover, powdered green tea has a higher inhibition effect of reactive oxygen species (ROS production in vitro compared with the same amount of leaf tea. Our data suggest that powdered green tea might have a different function from leaf tea due to the higher catechin contents and particles.

  17. Ingestion of green tea with lowered caffeine improves sleep quality of the elderly via suppression of stress

    OpenAIRE

    Unno, Keiko; Noda, Shigenori; Kawasaki, Yohei; Yamada, Hiroshi; Morita, Akio; Iguchi, Kazuaki; Nakamura, Yoriyuki

    2017-01-01

    Epidemiological and animal studies have demonstrated that ingestion of green tea enhances healthy life. However, caffeine in green tea can interfere with sleep. In this report, we examined the effect of green tea with lowered caffeine, low-caffeine green tea, on stress and sleep of the elderly. The participants (n = 10, mean age 89.3 ± 4.2 years) drank five cups/day of standard green tea for 1 week. Subsequently, they drank five cups/day of low-caffeine green tea for 2 weeks. Salivary α-amyla...

  18. Functions and mechanisms of green tea catechins in regulating bone remodeling.

    Science.gov (United States)

    Shen, Chwan-Li; Kwun, In-Sook; Wang, Shu; Mo, Huanbiao; Chen, Lixia; Jenkins, Marjorie; Brackee, Gordon; Chen, Chung-Hwan; Chyu, Ming-Chien

    2013-12-01

    Osteoporosis is caused by an imbalance in bone remodeling, a process involving bone-building osteoblasts and bone-resorptive osteoclasts. Excessive reactive oxygen species and inflammatory responses have been shown to stimulate differentiation and function of osteoclasts while inducing osteoblast apoptosis and suppressing osteoblastic proliferation and differentiation via extracellular signal-regulated kinases (ERK), ERK-dependent nuclear factor-κB and Wnt/β-catenin signaling pathways. The anti-oxidant and anti-inflammatory green tea catechins (GTC) have been shown to promote osteoblastogenesis, suppress osteoclastogenesis and stimulate the differentiation of mesenchymal stem cells into osteoblasts rather than adipocytes by modulating the signaling pathways. This paper reviews the pharmacokinetics and metabolism of GTC, their bone-protective activities evidenced in in vitro and in vivo studies, and the limited clinical studies supporting these preclinical findings. In light of the physical, economical, and social burdens due to osteoporosis, easily accessible and affordable preventive measures such as GTC deserves further clinical studies prior to its clinical application.

  19. In vitro transdermal delivery of caffeine, theobromine, theophylline and catechin from extract of Guarana, Paullinia Cupana.

    Science.gov (United States)

    Heard, Charles M; Johnson, Sarah; Moss, Gary; Thomas, Chris P

    2006-07-06

    Extracts of guarana (Paullinia cupana) feature as putatively stimulating ingredients in a number of foods, drinks and dietary/herbal supplements. The objective of this work was to investigate in vitro the transdermal delivery of the major pharmacologically active compounds contained in guarana extract. Saturated solutions of guarana were prepared in polyethylene glycol 400 (PEG400), propylene glycol (PG) and H(2)O at 32 degrees C. Guarana extract was also formulated in Duro-tak 2287 transdermal adhesive in a range of concentrations and the diffusional release was determined in addition to adhesive properties. Transdermal delivery across full thickness pig ear skin was investigated in vitro using Franz-type diffusion cells, with reverse-phase HPLC being used for the quantification of the permeation of theobromine (TB), theophylline (TP), (+)-catechin (C) and caffeine (CF). Based upon a combination of release and adhesive property data a patch containing 5.55 mg guarana extract cm(-2) was deemed optimal. The general trend for the delivery of the 4 analytes was: water >5.55 mg cm(-2) patch approximately PG>PEG400. For CF the greatest steady state flux was obtained from the water vehicle: 19 microg cm(-2)h(-1), with approximately 420 microg cm(-2) permeating after 24h. This was some 6x times more than from the drug-in-adhesive patch and 10x greater than PG, a well-known penetration enhancer, and 50x that of the 'regular' excipient PEG400. A water vehicle also provided the greatest delivery of TB (0.45 microg cm(-2) h(-1)), TP (0.022 microg cm(-2) h(-1)), and C (0.10 microg cm(-2) h(-1)). An inverse relationship was noted between lipophilicity and k(p) in each vehicle. The simultaneous transdermal delivery of the major actives of guarana was established, with permeation rates being highly concentration and vehicle dependent.

  20. Analysis of caffeine and heavy metal contents in branded and unbranded tea available in Pakistan

    International Nuclear Information System (INIS)

    Khan, S.R.; Inayat, A.; Chowdhry, M.N.; Waheed, A.

    2010-01-01

    In the investigation of caffeine and heavy metal contents in four branded and six unbranded tea samples collected from local markets of Lahore, Faisalabad and Peshawar, the amount of caffeine and heavy metals in all the branded tea samples were in agreement with the international standards. In unbranded tea samples, though the amount of caffeine was within standard limits but two of the samples collected from Peshawar had high concentrations of lead being, 13.69 and 15.78 mg/kg, consumption of which can lead to serious problems. (author)

  1. Inhibitory Effects of Eight Green Tea Catechins on Cytochrome P450 1A2, 2C9, 2D6, and 3A4 Activities.

    Science.gov (United States)

    Satoh, Takashi; Fujisawa, Haruka; Nakamura, Ami; Takahashi, Natsuko; Watanabe, Kazuhiro

    2016-01-01

    Green tea is a traditional beverage that has been enjoyed by the Japanese to this day. Recently, there has been an increase in the consumption of green tea beverage having high concentrations of catechins, such as (-)-epigallocatechin-3-O-gallate (EGCG). Many people tend to ingest large amounts of catechins through the frequent consumption of green tea beverage, and this dietary habit may lead to unwanted interactions between the catechins in green tea and medicinal drug. The inhibitory effects of eight green tea catechins on drug metabolizing enzymes, cytochrome P450 (CYP) 1A2, 2C9, 2D6, and 3A4, were investigated in human liver microsomes. Incubation was initiated by the addition of cocktail probe drugs that served as specific substrates for each CYP, and the resulting metabolites were analyzed by LC-MS. From a comparison of the fifty percent inhibitory concentration (IC50) values of the eight green tea catechins, it was found that non-gallated catechins did not inhibit CYPs, whereas gallated catechins inhibited all CYPs except CYP2D6. Among them, CYP2C9 was most strongly inhibited by (-)-catechin-3-O-gallate (CG) (7.60 µM), and CYP1A2 was most strongly inhibited by EGCG (8.93 µM). Catechin gallate exhibited non-competitive inhibition of CYP2C9, and its Ki value was 9.76 ± 0.47µM. The present study is the first to report the inhibitory effect of CG on CYP2C9. In contrast, EGCG showed competitive inhibition of CYP1A2, and its Ki value was 14.3 ± 0.09 µM. Previous reports had predicted that plasma EGCG concentration reached 7.4 µM after ingesting green tea having high concentrations of catechins. That concentration of EGCG is equivalent to one-half to one-third of its Ki value for CYP1A2 and CYP3A4 in this study. The ingestion of beverages containing large amounts of green tea catechins together with drugs that are metabolized by CYP1A2, CYP2C9, and CYP3A4 should be avoided. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For

  2. Theanine and Caffeine Content of Infusions Prepared from Commercial Tea Samples.

    Science.gov (United States)

    Boros, Klára; Jedlinszki, Nikoletta; Csupor, Dezső

    2016-01-01

    Caffeine and L-theanine are pharmacologically important constituents of tea, especially due to their effects on the central nervous system. The effects of these two compounds are opposite: While caffeine is a well-known stimulant, theanine has a relaxing effect. Tea processing may influence the caffeine and theanine content of tea leaves. The aim of our work was to quantify these constituents from a set of commercial products to reveal the possible correlations of caffeine and theanine content and processing methods. Theanine and caffeine contents of 37 commercial white, green, oolong, black, and pu-erh tea samples were quantified by high-performance liquid chromatography-diode array detector. The mean L-theanine content of white, green, oolong, and black teas were 6.26, 6.56, 6.09, and 5.13 mg/g, respectively. The same values for caffeine content were 16.79, 16.28, 19.31, and 17.73 mg/g. Though the effect of processing on theanine content was evident, quantification for these analytes does not seem to be a good criterion to discriminate the different types of tea. Caffeine content provided no information on the effect of processing, and the theanine content of the samples was rather variable, independently from the type of the tea. The quantitative analysis of caffeine and theanine is essential to assess the stimulating effect of the tea, however, for chemical profiling further secondary metabolites have to be determined. Thirty-seven commercial white, green, oolong, black, and pu-erh tea samples were analyzed for caffeine and theanine contentWhile the caffeine content was similar, the theanine contents of black teas were slightly lower and practically zero in pu-erhThe great variability of these two compound within the tea categories allows no discrimination of tea types based solely on theanine and caffeine quantificationContrary to the previous data, the way of processing has no determining effect on theanine content. FigureAbbreviations used: CZE: Capillary

  3. Green tea catechins potentiate the effect of antibiotics and modulate adherence and gene expression in Porphyromonas gingivalis.

    Science.gov (United States)

    Fournier-Larente, Jade; Morin, Marie-Pierre; Grenier, Daniel

    2016-05-01

    A number of studies have brought evidence that green tea catechins may contribute to periodontal health. The objective of this study was to investigate the ability of a green tea extract and its principal constituent epigallocatechin-3-gallate (EGCG) to potentiate the antibacterial effects of antibiotics (metronidazole, tetracycline) against Porphyromonas gingivalis, and to modulate the adherence to oral epithelial cells and expression of genes coding for virulence factors and the high temperature requirement A (HtrA) stress protein in P. gingivalis. A broth microdilution assay was used to determine the antibacterial activity of the green tea extract and EGCG. The synergistic effects of either compounds in association with metronidazole or tetracycline were evaluated using the checkerboard technique. A fluorescent assay was used to determine bacterial adherence to oral epithelial cells. The modulation of gene expression in P. gingivalis was evaluated by quantitative RT-PCR. The Vibrio harveyi bioassay was used for monitoring quorum sensing inhibitory activity. The MIC values of the green tea extract on P. gingivalis ranged from 250 to 1000 μg/ml, while those of EGCG ranged from 125 to 500 μg/ml. A marked synergistic effect on P. gingivalis growth was observed for the green tea extract or EGCG in combination with metronidazole. Both the green tea extract and EGCG caused a dose-dependent inhibition of P. gingivalis adherence to oral epithelial cells. On the one hand, green tea extract and EGCG dose-dependently inhibited the expression of several P. gingivalis genes involved in host colonization (fimA, hagA, hagB), tissue destruction (rgpA, kgp), and heme acquisition (hem). On the other hand, both compounds increased the expression of the stress protein htrA gene. The ability of the green tea extract and EGCG to inhibit quorum sensing may contribute to the modulation of gene expression. This study explored the preventive and therapeutic potential of green tea

  4. Caffeine Concentrations in Coffee, Tea, Chocolate, and Energy Drink Flavored E-liquids

    Science.gov (United States)

    Lisko, Joseph G.; Lee, Grace E.; Kimbrell, J. Brett; Rybak, Michael E.; Valentin-Blasini, Liza; Watson, Clifford H.

    2017-01-01

    Introduction Most electronic cigarettes (e-cigarettes) contain a solution of propylene glycol/glycerin and nicotine, as well as flavors. E-cigarettes and their associated e-liquids are available in numerous flavor varieties. A subset of the flavor varieties include coffee, tea, chocolate, and energy drink, which, in beverage form, are commonly recognized sources of caffeine. Recently, some manufacturers have begun marketing e-liquid products as energy enhancers that contain caffeine as an additive. Methods A Gas Chromatography-Mass Spectrometry (GC-MS) method for the quantitation of caffeine in e-liquids was developed, optimized and validated. The method was then applied to assess caffeine concentrations in 44 flavored e-liquids from cartridges, disposables, and refill solutions. Products chosen were flavors traditionally associated with caffeine (ie, coffee, tea, chocolate, and energy drink), marketed as energy boosters, or labeled as caffeine-containing by the manufacturer. Results Caffeine was detected in 42% of coffee-flavored products, 66% of tea-flavored products, and 50% of chocolate-flavored e-liquids (limit of detection [LOD] – 0.04 μg/g). Detectable caffeine concentrations ranged from 3.3 μg/g to 703 μg/g. Energy drink-flavored products did not contain detectable concentrations of caffeine. Eleven of 12 products marketed as energy enhancers contained caffeine, though in widely varying concentrations (31.7 μg/g to 9290 μg/g). Conclusions E-liquid flavors commonly associated with caffeine content like coffee, tea, chocolate, and energy drink often contained caffeine, but at concentrations significantly lower than their dietary counterparts. Estimated daily exposures from all e-cigarette products containing caffeine were much less than ingestion of traditional caffeinated beverages like coffee. Implications This study presents an optimized and validated method for the measurement of caffeine in e-liquids. The method is applicable to all e

  5. Caffeine Concentrations in Coffee, Tea, Chocolate, and Energy Drink Flavored E-liquids.

    Science.gov (United States)

    Lisko, Joseph G; Lee, Grace E; Kimbrell, J Brett; Rybak, Michael E; Valentin-Blasini, Liza; Watson, Clifford H

    2017-04-01

    Most electronic cigarettes (e-cigarettes) contain a solution of propylene glycol/glycerin and nicotine, as well as flavors. E-cigarettes and their associated e-liquids are available in numerous flavor varieties. A subset of the flavor varieties include coffee, tea, chocolate, and energy drink, which, in beverage form, are commonly recognized sources of caffeine. Recently, some manufacturers have begun marketing e-liquid products as energy enhancers that contain caffeine as an additive. A Gas Chromatography-Mass Spectrometry (GC-MS) method for the quantitation of caffeine in e-liquids was developed, optimized and validated. The method was then applied to assess caffeine concentrations in 44 flavored e-liquids from cartridges, disposables, and refill solutions. Products chosen were flavors traditionally associated with caffeine (ie, coffee, tea, chocolate, and energy drink), marketed as energy boosters, or labeled as caffeine-containing by the manufacturer. Caffeine was detected in 42% of coffee-flavored products, 66% of tea-flavored products, and 50% of chocolate-flavored e-liquids (limit of detection [LOD] - 0.04 µg/g). Detectable caffeine concentrations ranged from 3.3 µg/g to 703 µg/g. Energy drink-flavored products did not contain detectable concentrations of caffeine. Eleven of 12 products marketed as energy enhancers contained caffeine, though in widely varying concentrations (31.7 µg/g to 9290 µg/g). E-liquid flavors commonly associated with caffeine content like coffee, tea, chocolate, and energy drink often contained caffeine, but at concentrations significantly lower than their dietary counterparts. Estimated daily exposures from all e-cigarette products containing caffeine were much less than ingestion of traditional caffeinated beverages like coffee. This study presents an optimized and validated method for the measurement of caffeine in e-liquids. The method is applicable to all e-liquid matrices and could potentially be used to ensure regulatory

  6. Simultaneous determination of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in standard reference material baking chocolate 2384, cocoa, cocoa beans, and cocoa butter.

    Science.gov (United States)

    Risner, Charles H

    2008-01-01

    A reverse-phase liquid chromatography analysis is used to access the quantity of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in Standard Reference Material 2384 Baking Chocolate, cocoa, cocoa beans, and cocoa butter using water or a portion of the mobile phase as the extract. The procedure requires minimal sample preparation. Theobromine, (+)-catechin, caffeine, and (-)-epicatechin are detected by UV absorption at 273 nm after separation using a 0.3% acetic acid-methanol gradient (volume fractions) and quantified using external standards. The limit of detection for theobromine, (+)-catechin, caffeine, and (-)-epicatechin averages 0.08, 0.06, 0.06, and 0.06 microg/mL, respectively. The method when applied to Standard Reference Material 2384 Baking Chocolate; baking chocolate reference material yields results that compare to two different, separate procedures. Theobromine ranges from 26000 mg/kg in cocoa to 140 mg/kg in cocoa butter; (+)-catechin from 1800 mg/kg in cocoa to below detection limits of theobromine, 100.0 +/- 0.6 for (+)-catechin, 96.2 +/- 2.1 for caffeine, and 106.2 +/- 1.7 for (-)-epicatechin.

  7. Separation of Caffeine and Tea Poly-phenols from Instant (Soluble) Tea Waste Liquor by Macro-porous Resins

    OpenAIRE

    Xueling Gao; Bin Zhang; Zenglang Shao; Yong Yang; Pengxiang Yue

    2014-01-01

    Instant tea is presently manufactured by spraying and freeze drying the concentrated brew of processed tea leaves and dust. The purpose of this study was to develop a technique using macro-porous resins for separating Caffeine (Caf) and Tea Poly-phenols (TP) from the waste liquor generated by manufacturing instant tea. Optimum adsorption conditions were obtained using an initial concentration of Caf solution of 80 mg/L and a flow rate of 1.5 mL/min at 60°C; The optimal desorption conditions w...

  8. Preparation of catechin extracts and nanoemulsions from green tea leaf waste and their inhibition effect on prostate cancer cell PC-3

    Directory of Open Access Journals (Sweden)

    Tsai YJ

    2016-05-01

    Full Text Available Yin-Jieh Tsai, Bing-Huei ChenDepartment of Food Science, Fu Jen Catholic University, New Taipei City, Taiwan, Republic of China Abstract: Green tea is one of the most commonly consumed natural health beverages in Taiwan’s market, with the major functional component catechin being shown to possess several biological activities such as antioxidation, anticancer, and prevention of cardiovascular disease. The objectives of this study were to develop a high-performance liquid chromatography–mass spectrometry method to determine the variety and content of catechins in green tea leaf waste, a by-product obtained during processing of tea beverage. In addition, catechin nanoemulsion was prepared to study its inhibition effect on prostate cancer cell PC-3. Results showed that a total of eight catechin standards were separated within 25 minutes by using a Gemini C18 column and a gradient mobile phase of 0.1% formic acid (A and acetonitrile (B with flow rate at 1 mL/min, column temperature at 30°C, and detection wavelength at 280 nm. Among various extraction solvents, 50% ethanol generated the highest yield of total catechins from tea leaf waste, of which five catechins were identified and quantified. The catechin nanoemulsion was composed of catechin extract, lecithin, Tween 80, and deionized water in an appropriate proportion, with the mean particle size being 11.45 nm, encapsulation efficiency 88.1%, and zeta potential -66.3 mV. A high stability of catechin nanoemulsion was shown over a storage period of 120 days at 4°C. Both catechin extract and nanoemulsion could inhibit growth of PC-3 tumor cells, with the half maximal inhibitory concentration being 15.4 µg/mL and 8.5 µg/mL, respectively. The PC-3 cell cycle was arrested at S phase through elevation of P27 expression and decline of cyclin A, cyclin B, cyclin-dependent kinase 2, and cyclin-dependent kinase 1 expression. In addition, both catechin extract and nanoemulsion could induce

  9. Association mapping of caffeine content with TCS1 in tea plant and its related species.

    Science.gov (United States)

    Jin, Ji-Qiang; Yao, Ming-Zhe; Ma, Chun-Lei; Ma, Jian-Qiang; Chen, Liang

    2016-08-01

    Caffeine is the most abundant purine alkaloid in majority of tea plant and its related species. This purine alkaloid contributes to the important flavor and health attributes of tea. Tea caffeine synthase 1 (TCS1, EC 2.1.1.159/2.1.1.160) gene plays a crucial role in caffeine biosynthesis. The objective of this study was to investigate the genetic relationship between the TCS1 and caffeine content of tea plant and its related species using association mapping. We identified 87 single-nucleotide polymorphisms (SNPs, π = 0.00447) by resequencing the TCS1 locus of 44 tea accessions. Linkage disequilibrium (LD) analysis showed that LD did not extend over the entire gene (r(2) caffeine content in four environments, explaining 4.0%-7.7% of the phenotypic variance. We also validated the significant marker-trait associations in site-directed mutagenesis experiments. Examination of allelic variation and linkage disequilibrium by a candidate-gene-based approach can help to decipher the genetic basis of caffeine biosynthesis. Moreover, the SNP marker identified in this study can potentially be applied for future marker-assisted selection to improve tea quality. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Biosynthesis of caffeine by tea-leaf extracts. Enzymic formation of theobromine from 7-methylxanthine and of caffeine from theobromine.

    Science.gov (United States)

    Suzuki, T; Takahashi, E

    1975-01-01

    1. Extracts prepared from tea leaves with Polyclar AT (insoluble polyvinylpyrrolidine) contained two methyltransferase activities catalysing the transfer of methyl groups from S-adenosylmethionine to 7-methylxanthine, producing theobromine, and to theobromine, producing caffeine. 2. The methyltransferases exhibited the same pH optimum (8.4) and a similar pattern of effects by metal ions, thiol inhibitors and metal-chelating reagents, both for theobromine and caffeine synthesis. Mg2+, Mn2+ and Ca2+ slightly stimulated enzyme activity but they were not essential. Paraxanthine was shown to be most active among methylxanthines, as the methyl acceptor. However, the formation of paraxanthine from 1-methylxanthine was very low and that from 7-methylxanthine was nil, suggesting that the synthesis of caffeine from paraxanthine is of little importance in intact plants. Xanthine, xanthosine, XMP and hypoxanthine were all inactive as methyl acceptors, whereas [2(-14)C]xanthine and [8(-14)C]hypoxanthine were catabolized to allantoin and urea by tea-leaf extracts. The apparent Km values are as follows: 7-methylxanthine, 1.0 times 10(-14)M; theobromine, 1.0 times 10(-3)M; paraxanthine, 0.2 times 10(-3)M; S-adenosylmethionine, 0.25 times 10(-4)M (with each of the three substrates). 3. The results suggest that the pathway for caffeine biosynthesis is as follows: 7-methylxanthine leads to theobromine leads to caffeine. In contrast, it is suggested that theophylline is synthesized from 1-methylxanthine. The methyl groups of the purine ring of caffeine are all derived directly from the methyl group of S-adenosylmethionine. Little is known about the pathways leading to the formation of 7-methylxanthine. 4. A good correlation between caffeine synthesis and shoot formation or growth of tea seedlings was shown, suggesting that the methylating systems in caffeine synthesis are closely associated with purine nucleotide and nucleic acid metabolism in tea plants. PMID:238504

  11. Reduced Stress and Improved Sleep Quality Caused by Green Tea Are Associated with a Reduced Caffeine Content

    OpenAIRE

    Unno, Keiko; Noda, Shigenori; Kawasaki, Yohei; Yamada, Hiroshi; Morita, Akio; Iguchi, Kazuaki; Nakamura, Yoriyuki

    2017-01-01

    Caffeine, one of the main components in green tea, can interfere with sleep and block the effect of theanine. Since theanine, the main amino acid in tea leaves, has significant anti-stress effects in animals and humans, we examined the effects of green tea with lowered caffeine content, i.e., low-caffeine green tea (LCGT), on stress and quality of sleep of middle–aged individuals (n = 20, mean age 51.3 ± 6.7 years) in a double-blind crossover design. Standard green tea (SGT) was used as the c...

  12. Coffee, tea, and caffeine consumption and risk of epithelial ovarian cancer and borderline ovarian tumors

    DEFF Research Database (Denmark)

    Gosvig, Camilla F; Kjaer, Susanne K; Blaakær, Jan

    2015-01-01

    BACKGROUND: Epidemiological studies that have investigated the association between coffee, tea and caffeine consumption and ovarian cancer risk have produced conflicting results. Furthermore, only few studies have examined the role of coffee and tea consumption separately for borderline ovarian...... tumors. By use of data from a large Danish population-based case-control study, we examined the risk of ovarian tumors associated with coffee, tea, and caffeine consumption with a particular focus on characterizing risks by tumor behavior and histology. MATERIAL AND METHODS: From 1995 through 1999, we....... RESULTS: Both coffee (OR = 0.90; 95% CI 0.84-0.97 per cup/day) and total caffeine consumption from coffee and tea combined (OR = 0.93; 95% CI 0.88-0.98 per 100 mg/day) decreased the risk of ovarian cancer. These associations were significant only for the serous and "other" subtypes of ovarian cancer...

  13. Effects of supplementation with green tea catechins on plasma C-reactive protein concentrations: A systematic review and meta-analysis of randomized controlled trials.

    Science.gov (United States)

    Serban, Corina; Sahebkar, Amirhossein; Antal, Diana; Ursoniu, Sorin; Banach, Maciej

    2015-09-01

    Promising experimental and clinical trials suggest that green tea decreases the inflammatory process in cardiometabolic diseases, but evidence from epidemiologic studies about the effects on plasma C-reactive protein (CRP) seems inconsistent and ambiguous. Therefore, the aim of this meta-analysis was to evaluate the effects of green tea supplementation on plasma CRP concentrations. We searched selected database up to October 26, 2014 to identify randomized controlled trials (RCTs) investigating the effects of green tea supplementation on plasma CRP concentrations. Two independent reviewers extracted data on study characteristics, methods, and outcomes. Meta-analysis of data from 11 RCTs arms did not indicate a significant effect of supplementation with green tea catechins on plasma CRP concentrations (weighted mean difference [WMD], 0.085 mg/L; 95% confidence interval [CI], -0.225 to 0.395; P = 0.592). This effect size was robust in sensitivity analysis and omission of each individual study did not have a significant effect. The nonsignificant effects of green tea catechins on plasma CRP concentrations were also observed in subgroups of studies with green tea supplementation with a duration of green tea catechins on plasma CRP concentrations. Furthermore, well-designed trials are necessary to validate these results. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Molecular insights into the differences in anti-inflammatory activities of green tea catechins on IL-1β signaling in rheumatoid arthritis synovial fibroblasts.

    Science.gov (United States)

    Fechtner, Sabrina; Singh, Anil; Chourasia, Mukesh; Ahmed, Salahuddin

    2017-08-15

    In this study, we found that catechins found in green tea (EGCG, EGC, and EC) differentially interfere with the IL-1β signaling pathway which regulates the expression of pro-inflammatory mediators (IL-6 and IL-8) and Cox-2 in primary human rheumatoid arthritis synovial fibroblasts (RASFs). EGCG and EGC inhibited IL-6, IL-8, and MMP-2 production and selectively inhibited Cox-2 expression. EC did not exhibit any inhibitory effects. When we looked at the expression of key signaling proteins in the IL-1β signaling pathway, we found all the tested catechins could inhibit TAK-1 activity. Therefore, the consumption of green tea offers an overall anti-inflammatory effect. Molecular docking analysis confirms that EGCG, EGC, and EC all occupy the active site of the TAK1 kinase domain. However, EGCG occupies the majority of the TAK1 active site. In addition to TAK1 inhibition, EGCG can also inhibit P38 and nuclear NF-κB expression whereas EC and EGC were not effective inhibitors. Our findings suggest one of the main health benefits associated with the consumption of green tea are due to the activity of EGCG and EGC which are both present at higher amounts. Although EGCG is the most effective catechin at inhibiting downstream inflammatory signaling, its effectiveness could be hindered by the presence of EC. Therefore, varying EC content in green tea may reduce the anti-inflammatory effects of other potential catechins in green tea. Copyright © 2017. Published by Elsevier Inc.

  15. Ingestion of green tea with lowered caffeine improves sleep quality of the elderly via suppression of stress

    Science.gov (United States)

    Unno, Keiko; Noda, Shigenori; Kawasaki, Yohei; Yamada, Hiroshi; Morita, Akio; Iguchi, Kazuaki; Nakamura, Yoriyuki

    2017-01-01

    Epidemiological and animal studies have demonstrated that ingestion of green tea enhances healthy life. However, caffeine in green tea can interfere with sleep. In this report, we examined the effect of green tea with lowered caffeine, low-caffeine green tea, on stress and sleep of the elderly. The participants (n = 10, mean age 89.3 ± 4.2 years) drank five cups/day of standard green tea for 1 week. Subsequently, they drank five cups/day of low-caffeine green tea for 2 weeks. Salivary α-amylase activity (sAA) was measured as a stress marker. Sleep stages were measured using a portable electroencephalography (n = 7, 6 female and 1 male). The level of sAA in the morning (sAAm) was significantly lower when the participants drank low-caffeine green tea than standard green tea. While the levels of sAAm were different among individuals, lower sAAm correlated with a higher quality of sleep. In those participants whose sAAm was lowered by the ingestion of low-caffeine green tea, some sleep parameters improved. Daily ingestion of low-caffeine green tea may be a beneficial tool for improving the quality of sleep of the elderly via the suppression of stress, although further research is required to fortify this hypothesis. PMID:29203963

  16. Ingestion of green tea with lowered caffeine improves sleep quality of the elderly via suppression of stress.

    Science.gov (United States)

    Unno, Keiko; Noda, Shigenori; Kawasaki, Yohei; Yamada, Hiroshi; Morita, Akio; Iguchi, Kazuaki; Nakamura, Yoriyuki

    2017-11-01

    Epidemiological and animal studies have demonstrated that ingestion of green tea enhances healthy life. However, caffeine in green tea can interfere with sleep. In this report, we examined the effect of green tea with lowered caffeine, low-caffeine green tea, on stress and sleep of the elderly. The participants ( n  = 10, mean age 89.3 ± 4.2 years) drank five cups/day of standard green tea for 1 week. Subsequently, they drank five cups/day of low-caffeine green tea for 2 weeks. Salivary α-amylase activity (sAA) was measured as a stress marker. Sleep stages were measured using a portable electroencephalography ( n  = 7, 6 female and 1 male). The level of sAA in the morning (sAAm) was significantly lower when the participants drank low-caffeine green tea than standard green tea. While the levels of sAAm were different among individuals, lower sAAm correlated with a higher quality of sleep. In those participants whose sAAm was lowered by the ingestion of low-caffeine green tea, some sleep parameters improved. Daily ingestion of low-caffeine green tea may be a beneficial tool for improving the quality of sleep of the elderly via the suppression of stress, although further research is required to fortify this hypothesis.

  17. Bactericidal activity of green tea extracts: the importance of catechin containing nano particles

    OpenAIRE

    Gopal, Judy; Muthu, Manikandan; Paul, Diby; Kim, Doo-Hwan; Chun, Sechul

    2016-01-01

    When we drink green tea infusion, we believe we are drinking the extract of the green tea leaves. While practically each tea bag infused in 300?mL water contains about 50?mg of suspended green tea leaf particles. What is the role of these particles in the green tea effect is the objective of this study. These particles (three different size ranges) were isolated via varying speed centrifugation and their respective inputs evaluated. Live oral bacterial samples from human volunteers have been ...

  18. Effect of green tea catechins in patients with high-grade prostatic intraepithelial neoplasia: Results of a short-term double-blind placebo controlled phase II clinical trial

    Directory of Open Access Journals (Sweden)

    Salvatore Micali

    2017-10-01

    Full Text Available Background and study objective: Several studies suggest a protective role of green tea catechins against prostate cancer (PCa. In order to evaluate the efficacy of green tea catechins for chemoprevention of PCa in patients with high-grade prostate intraepithelial neoplasia (HG-PIN we performed a phase II clinical trial. Methods: Sixty volunteers with HG-PIN were enrolled to carry out a double-blind randomized placebo-controlled phase II clinical trial. Treated group took daily 600 mg of green tea catechins (Categ Plus® for 1 year. Patients were screened at 6 and 12 months through prostatic biopsy and measurements of prostate-specific antigen (PSA. Results: Despite the statistically significant reduction of PSA observed in subjects who received green tea catechins for 6 and 12 months, we did not find any statistical difference in PCa incidence between the experimental groups neither after 6 nor after 12 months. However, throughout the one-year follow- up we observed very limited adverse effects induced by green tea catechins and a not significant improvement in lower urinary tract symptoms and quality of life. Conclusions: Although the small number of patients enrolled in our study and the relatively short duration of intervention, our findings seems to deny the efficacy of green tea catechins. However, results of our clinical study, mainly for its low statistical strength, suggest that the effectiveness of green tea catechins should be evaluated in both a larger cohort of men and longer trial.

  19. Green tea and type 2 diabetes

    Directory of Open Access Journals (Sweden)

    Jae-Hyung Park

    2014-03-01

    Full Text Available Green tea and coffee consumption have been widely popular worldwide. These beverages contain caffeine to activate the central nervous system by adenosine receptor blockade, and due to the caffeine, addiction or tolerance may occur. In addition to this caffeine effect, green tea and coffee consumption have always been at the center of discussions about human health, disease, and longevity. In particular, green tea catechins are involved in many biological activities such as antioxidation and modulation of various cellular lipid and proteins. Thus, they are beneficial against degenerative diseases, including obesity, cancer, cardiovascular diseases, and various inflammatory diseases. Some reports also suggest that daily consumption of tea catechins may help in controlling type 2 diabetes. However, other studies have reported that chronic consumption of green tea may result in hepatic failure, neuronal damage, and exacerbation of diabetes, suggesting that interindividual variations in the green tea effect are large. This review will focus on the effect of green tea catechins extracted from the Camellia sinensis plant on type 2 diabetes and obesity, and the possible mechanistic explanation for the experimental results mainly from our laboratory. It is hoped that green tea can be consumed in a suitable manner as a supplement to prevent the development of type 2 diabetes and obesity.

  20. Orthogonal analytical methods for botanical standardization: determination of green tea catechins by qNMR and LC-MS/MS.

    Science.gov (United States)

    Napolitano, José G; Gödecke, Tanja; Lankin, David C; Jaki, Birgit U; McAlpine, James B; Chen, Shao-Nong; Pauli, Guido F

    2014-05-01

    The development of analytical methods for parallel characterization of multiple phytoconstituents is essential to advance the quality control of herbal products. While chemical standardization is commonly carried out by targeted analysis using gas or liquid chromatography-based methods, more universal approaches based on quantitative (1)H NMR (qHNMR) measurements are being used increasingly in the multi-targeted assessment of these complex mixtures. The present study describes the development of a 1D qHNMR-based method for simultaneous identification and quantification of green tea constituents. This approach utilizes computer-assisted (1)H iterative Full Spin Analysis (HiFSA) and enables rapid profiling of seven catechins in commercial green tea extracts. The qHNMR results were cross-validated against quantitative profiles obtained with an orthogonal LC-MS/MS method. The relative strengths and weaknesses of both approaches are discussed, with special emphasis on the role of identical reference standards in qualitative and quantitative analyses. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Proximate, caffeine and tannin analyses in some brands of tea ...

    African Journals Online (AJOL)

    China, Kenya, India, Srilanka and Mambilla) tea leaves samples sold in Kano markets was conducted. The moisture content was generally high in all the tea samples and ranged from 5.6% in Mambila to 7.5% in India samples. Ash content was ...

  2. proximate, caffeine and tannin analyses in some brands of tea ...

    African Journals Online (AJOL)

    DR. AMINU

    (Kumar et al., 2005). Sahito et al. (2005) reported the contents of fifteen essential trace and toxic elements in some green tea samples and in their infusion. Karimi et al. (2008) worked on the concentrations and health risk of metals in tea samples marketed in Iran. Effects of tannase treatment and protein tannin aggregation.

  3. The single and synergistic effects of the major tea components caffeine, epigallocatechin-3-gallate and L-theanine on rat sperm viability.

    Science.gov (United States)

    Dias, Tânia R; Alves, Marco G; Casal, Susana; Silva, Branca M; Oliveira, Pedro F

    2016-03-01

    Caffeine, epigallocatechin-3-gallate (EGCG) and L-theanine are the major components of tea (Camellia sinensis L.) and the main representatives of the classes of methylxanthines, catechins and free amino acids present in this beverage. There are many studies reporting tea's health benefits, however it is not clear if those effects are mediated by a single component or a synergistic action. This study aimed to evaluate the individual and synergistic effects of tea's major components on rat epididymal spermatozoa survival and oxidative profile during 3-day storage at room temperature (RT). For that, spermatozoa were incubated with caffeine (71 μg mL(-1)), EGCG (82 μg mL(-1)), or L-theanine (19 μg mL(-1)), alone or in combination. Spermatozoa viability was assessed by the eosin-nigrosin staining technique. The oxidative profile was established by evaluating the levels of carbonyl groups, protein nitration and lipid peroxidation. Supplementation of sperm storage medium with the three compounds together improved sperm viability, after 24, 48 and 72 h of incubation, relative to the control and the groups incubated with each component individually. However, at the end of the 72 h of incubation, there was an increase in protein oxidation in the group exposed to the three compounds, illustrating that the combined treatment triggers different alterations in sperm proteins during their maturational process in the epididymis. This study highlights the importance of the synergism between tea components for the beneficial effects usually attributed to this beverage, particularly in sperm storage at RT.

  4. Effect of green tea catechin, a local drug delivery system as an adjunct to scaling and root planing in chronic periodontitis patients: A clinicomicrobiological study

    Directory of Open Access Journals (Sweden)

    Praveen Kudva

    2011-01-01

    Full Text Available Background: Evaluate the adjunctive use of locally delivered green tea catechin with scaling and root planing, as compared to scaling and root planing alone in the management of chronic periodontitis. Materials and Methods: Fourteen patients with two sites in the contralateral quadrants with probing pocket depth of 5−8mm were selected. Each of the sites was assessed for the plaque index, gingival index, and probing pocket depth at baseline and 21 days and for microbiological analysis at baseline, 1 week and 21 days. Test sites received scaling and root planing along with green tea catechin strips and control sites received scaling and root planning alone. Results: The result showed intercomparison of the plaque index and gingival index for test and control groups at 21 days was not significant with P>0.05, whereas the probing depth at 21 days was significant with P<0.001. Intercomparison between microbial results demonstrated a considerable reduction of occurrence of Aggregatibacter actinomycetemcomitans, Prevotella intermedia, Fusobacterium species and Capnocytophaga in test. Conclusion: Green tea catechin local delivery along with scaling and root planing is more effective than scaling and root planing alone.

  5. OPTIMIZATION OF A UV-VIS SPECTROMETRIC METHOD FOR CAFFEINE ANALYSIS IN TEA, COFFEE AND OTHER BEVERAGES

    Directory of Open Access Journals (Sweden)

    S. DOBRINAS

    2014-01-01

    Full Text Available A method has been developed and validated for the determination of caffeine in tea, coffee and other beverages by UV-VIS spectrometry. A linear calibration curve was generated with caffeine concentration ranging from 3 mg∙L-1 to 18 mg∙L-1. The procedure developed provides a 0.85 mg∙L-1 detection limit of caffeine, respectively 1.52 mg∙L-1 quantification limit and the relative standard deviation (RSD was less than 0.05 % for independent measurement. The developed method was sensitive/specific and robust. Caffeine in tea infusions was found to be dependent on infusion time, the longer of the infusion time and the higher of the caffeine concentrations in tea infusions.

  6. Psychological effects of dietary components of tea: caffeine and L-theanine.

    Science.gov (United States)

    Bryan, Janet

    2008-02-01

    This review summarizes the literature on the association between two dietary components of tea, caffeine and L-theanine, and the psychological outcomes of consumption; it also identifies areas for future research. The studies reviewed suggest that caffeinated tea, when ingested at regular intervals, may maintain alertness, focused attention, and accuracy and may modulate the more acute effects of higher doses of caffeine. These findings concur with the neurochemical effects of L-theanine on the brain. L-theanine may interact with caffeine to enhance performance in terms of attention switching and the ability to ignore distraction; this is likely to be reflective of higher-level cognitive activity and may be sensitive to the detrimental effects of overstimulation. Further research should investigate the interactive effects of caffeine, L-theanine, and task complexity, utilize a range of ecologically valid psychological outcomes, and assess the neuroprotective effects of L-theanine using epidemiological or longer-term intervention studies among individuals at risk of neurodegenerative disease.

  7. Analysis of cream formation in green tea concentrates with different solid concentrations

    OpenAIRE

    Xu, Yong-Quan; Chen, Su-Qin; Yuan, Hai-Bo; Tang, Ping; Yin, Jun-Feng

    2011-01-01

    The formation of tea cream in the green tea concentrates of different solid concentrations (5, 10, 20, 30, 40, 50 and 60°Brix) was investigated. The results showed a good positive correlation (γ = 0.98, p ≤ 0.05) between the amount of tea cream and the solid concentrations from 5 to 40°Brix, while the amount of tea cream in the tea concentrates of 50 and 60°Brix decreased acutely. Total sugar, caffeine and catechins were found to be the main chemical components of tea cream in the green tea c...

  8. Augmented cellular uptake of nanoparticles using tea catechins: effect of surface modification on nanoparticle-cell interaction

    Science.gov (United States)

    Lu, Yi-Ching; Luo, Pei-Chun; Huang, Chun-Wan; Leu, Yann-Lii; Wang, Tzu-Hao; Wei, Kuo-Chen; Wang, Hsin-Ell; Ma, Yunn-Hwa

    2014-08-01

    Nanoparticles may serve as carriers in targeted therapeutics; interaction of the nanoparticles with a biological system may determine their targeting effects and therapeutic efficacy. Epigallocatechin-3-gallate (EGCG), a major component of tea catechins, has been conjugated with nanoparticles and tested as an anticancer agent. We investigated whether EGCG may enhance nanoparticle uptake by tumor cells. Cellular uptake of a dextran-coated magnetic nanoparticle (MNP) was determined by confocal microscopy, flow cytometry or a potassium thiocyanate colorimetric method. We demonstrated that EGCG greatly enhanced interaction and/or internalization of MNPs (with or without polyethylene glycol) by glioma cells, but not vascular endothelial cells. The enhancing effects are both time- and concentration-dependent. Such effects may be induced by a simple mix of MNPs with EGCG at a concentration as low as 1-3 μM, which increased MNP uptake 2- to 7-fold. In addition, application of magnetic force further potentiated MNP uptake, suggesting a synergetic effect of EGCG and magnetic force. Because the effects of EGCG were preserved at 4 °C, but not when EGCG was removed from the culture medium prior to addition of MNPs, a direct interaction of EGCG and MNPs was implicated. Use of an MNP-EGCG composite produced by adsorption of EGCG and magnetic separation also led to an enhanced uptake. The results reveal a novel interaction of a food component and nanocarrier system, which may be potentially amenable to magnetofection, cell labeling/tracing, and targeted therapeutics.

  9. Total, caffeinated and decaffeinated coffee and tea intake and gastric cancer risk : Results from the EPIC cohort study

    NARCIS (Netherlands)

    Sanikini, Harinakshi; Dik, Vincent K.; Siersema, Peter D.; Bhoo-Pathy, Nirmala; Uiterwaal, Cuno S. P. M.; Peeters, Petra H. M.; Alez, Carlos A. Gonz; Zamora-Ros, Raul; Overvad, Kim; Nneland, Anne Tj; Roswall, Nina; Boutron-Ruault, Marie-Christine; Fagherazzi, Guy; Racine, Antoine; Kuehn, Tilman; Katzke, Verena; Boeing, Heiner; Trichopoulou, Antonia; Trichopoulos, Dimitrios; Lagiou, Pagona; Palli, Domenico; Grioni, Sara; Vineis, Paolo; Tumino, Rosario; Panico, Salvatore; Weiderpass, Elisabete; Skeie, Guri; Braaten, Tonje; Huerta, Jose Maria; Sanchez-Cantalejo, Emilio; Barricarte, Aurelio; Sonestedt, Emily; Wallstrom, Peter; Nilsson, Lena Maria; Johansson, Ingegerd; Bradbury, Kathryn E.; Khaw, Kay-Tee; Wareham, Nick; Huybrechts, Inge; Freisling, Heinz; Cross, Amanda J.; Riboli, Elio; Bueno-de-Mesquita, H. B(as)

    2015-01-01

    Prospective studies examining the association between coffee and tea consumption and gastric cancer risk have shown inconsistent results. We investigated the association between coffee (total, caffeinated and decaffeinated) and tea consumption and the risk of gastric cancer by anatomical site and

  10. Total, caffeinated and decaffeinated coffee and tea intake and gastric cancer risk: results from the EPIC cohort study

    NARCIS (Netherlands)

    Sanikini, H.; Dik, V.K.; Siersema, P.D.; Bhoo-Pathy, N.; Uiterwaal, C.S.; Peeters, P.H.M.; Gonzalez, C.A.; Zamora-Ros, R.; Overvad, K.; Tjonneland, A.; Roswall, N.; Boutron-Ruault, M.C.; Fagherazzi, G.; Racine, A.; Kuhn, T.; Katzke, V.; Boeing, H.; Trichopoulou, A.; Trichopoulos, D.; Lagiou, P.; Palli, D.; Grioni, S.; Vineis, P.; Tumino, R.; Panico, S.; Weiderpass, E.; Skeie, G.; Braaten, T.; Huerta, J.M.; Sanchez-Cantalejo, E.; Barricarte, A.; Sonestedt, E.; Wallstrom, P.; Nilsson, L.M.; Johansson, I.; Bradbury, K.E.; Khaw, K.T.; Wareham, N.; Huybrechts, I.; Freisling, H.; Cross, A.J.; Riboli, E.; Bueno-de-Mesquita, H.B.

    2015-01-01

    Prospective studies examining the association between coffee and tea consumption and gastric cancer risk have shown inconsistent results. We investigated the association between coffee (total, caffeinated and decaffeinated) and tea consumption and the risk of gastric cancer by anatomical site and

  11. Consumption of coffee, green tea, oolong tea, black tea, chocolate snacks and the caffeine content in relation to risk of diabetes in Japanese men and women.

    Science.gov (United States)

    Oba, Shino; Nagata, Chisato; Nakamura, Kozue; Fujii, Kaori; Kawachi, Toshiaki; Takatsuka, Naoyoshi; Shimizu, Hiroyuki

    2010-02-01

    Although the inverse association between coffee consumption and risk of diabetes has been reported numerous times, the role of caffeine intake in this association has remained unclear. We evaluated the consumption of coffee and other beverages and food containing caffeine in relation to the incidence of diabetes. The study participants were 5897 men and 7643 women in a community-based cohort in Takayama, Japan. Consumption of coffee, green tea, oolong tea, black tea and chocolate snacks were measured with a semi-quantitative FFQ in 1992. At the follow-up survey in 2002, the development of diabetes and the time of diagnosis were reported. To assess the association, age, smoking status, BMI, physical activity, education in years, alcohol consumption, total energy intake, fat intake and women's menopausal status were adjusted. Among men who consumed one cup per month to six cups per week and among those who consumed one cup per d or more, the associated hazard ratios were 0.69 (95 % CI 0.50, 0.97) and 0.69 (95 % CI 0.49, 0.98) compared with those who drank little to no coffee, with a P value for trend of 0.32. The hazard ratios for women with the same coffee consumption patterns were 1.08 (95 % CI 0.74, 1.60) and 0.70 (95 % CI 0.44, 1.12), with a P value for trend of 0.03. The association between estimated total caffeine intake and risk of diabetes was insignificant both among men and among women. The results imply that coffee consumption decreased the risk of developing diabetes. The protective effect may exist aside from the influence of caffeine intake.

  12. Total, caffeinated and decaffeinated coffee and tea intake and gastric cancer risk

    DEFF Research Database (Denmark)

    Sanikini, Harinakshi; Dik, Vincent K; Siersema, Peter D

    2015-01-01

    Prospective studies examining the association between coffee and tea consumption and gastric cancer risk have shown inconsistent results. We investigated the association between coffee (total, caffeinated and decaffeinated) and tea consumption and the risk of gastric cancer by anatomical site...... no significant association between overall gastric cancer risk and consumption of total coffee (HR 1.09, 95%-CI: 0.84-1.43; quartile 4 vs. non/quartile 1), caffeinated coffee (HR 1.14, 95%-CI: 0.82-1.59; quartile 4 vs. non/quartile 1), decaffeinated coffee (HR 1.07, 95%-CI: 0.75-1.53; tertile 3 vs. non/tertile 1...... association was observed between gastric cardia cancer risk and caffeinated coffee consumption (HR 1.98, 95%-CI: 1.16-3.36, P-trend=0.06; quartile 3 vs. non/quartile 1) and per increment of 100mL/day (HR 1.09, 95%-CI: 1.04-1.14). In conclusion, consumption of total, caffeinated and decaffeinated coffee...

  13. Alkaloid and polyphenol analysis by HPLC in green and black tea powders and their potential use as additives in ruminant diets

    Science.gov (United States)

    Ramdani, Diky; Chaudhry, Abdul S.; Seal, Chris J.

    2018-02-01

    We used HPLC to examine the bioactive compounds such as alkaloids and polyphenols in green and black tea powders and their use as potential additives in ruminant diets. Caffeine was the highest alkaloid in both green and black teas. Green tea had significantly higher concentrations of alkaloids and catechins but lower theaflavins than black tea. Epigallocatechin gallate, epicatechin gallate and epigallocatechin were the major catechins in green tea while theaflavin-3, 3'-digallate and theaflavin-3-gallate were the major theaflavins in black tea. Tea powders in ruminant diets decreased in vitro rumen ammonia and methane production without affecting volatile fatty acid profiles and the degradability of the diets. The tea powders containing variable amounts of alkaloids, catechins and theaflavins can potentially be used to decrease rumen ammonia and methane productions without any detrimental effect on rumen functions in vitro and perhaps ruminant productive efficiency.

  14. The Green Tea Catechin Epigallocatechin Gallate Ameliorates Graft-versus-Host Disease.

    Directory of Open Access Journals (Sweden)

    Sabine Westphal

    Full Text Available Allogeneic hematopoetic stem cell transplantation (allo-HSCT is a standard treatment for leukemia and other hematologic malignancies. The major complication of allo-HSCT is graft-versus-host-disease (GVHD, a progressive inflammatory illness characterized by donor immune cells attacking the organs of the recipient. Current GVHD prevention and treatment strategies use immune suppressive drugs and/or anti-T cell reagents these can lead to increased risk of infections and tumor relapse. Recent research demonstrated that epigallocatechin gallate (EGCG, a component found in green tea leaves at a level of 25-35% at dry weight, may be useful in the inhibition of GVHD due to its immune modulatory, anti-oxidative and anti-angiogenic capacities. In murine allo-HSCT recipients treated with EGCG, we found significantly reduced GVHD scores, reduced target organ GVHD and improved survival. EGCG treated allo-HSCT recipients had significantly higher numbers of regulatory T cells in GVHD target organs and in the blood. Furthermore, EGCG treatment resulted in diminished oxidative stress indicated by significant changes of glutathione blood levels as well as glutathione peroxidase in the colon. In summary, our study provides novel evidence demonstrating that EGCG ameliorates lethal GVHD and reduces GVHD-related target organ damage. Possible mechanisms are increased regulatory T cell numbers and reduced oxidative stress.

  15. Reduced Stress and Improved Sleep Quality Caused by Green Tea Are Associated with a Reduced Caffeine Content.

    Science.gov (United States)

    Unno, Keiko; Noda, Shigenori; Kawasaki, Yohei; Yamada, Hiroshi; Morita, Akio; Iguchi, Kazuaki; Nakamura, Yoriyuki

    2017-07-19

    Caffeine, one of the main components in green tea, can interfere with sleep and block the effect of theanine. Since theanine, the main amino acid in tea leaves, has significant anti-stress effects in animals and humans, we examined the effects of green tea with lowered caffeine content, i.e., low-caffeine green tea (LCGT), on stress and quality of sleep of middle-aged individuals ( n = 20, mean age 51.3 ± 6.7 years) in a double-blind crossover design. Standard green tea (SGT) was used as the control. These teas (≥300 mL/day), which were eluted with room temperature water, were consumed over a period of seven days after a single washout term. The level of salivary α-amylase activity (sAA), a stress marker, was significantly lower in participants that consumed LCGT (64.7 U/mL) than in those that consumed SGT (73.9 U/mL). Sleep quality was higher in participants that consumed a larger quantity of LCGT. In addition, a self-diagnostic check for accumulated fatigue was significantly lower in those participants that consumed LCGT than SGT. These results indicate that LCGT intake can reduce stress in middle-aged individuals and improve their quality of sleep. The reduction in caffeine is suggested to be a valid reason for enhancing the anti-stress effect of green tea.

  16. Reduced Stress and Improved Sleep Quality Caused by Green Tea Are Associated with a Reduced Caffeine Content

    Directory of Open Access Journals (Sweden)

    Keiko Unno

    2017-07-01

    Full Text Available Caffeine, one of the main components in green tea, can interfere with sleep and block the effect of theanine. Since theanine, the main amino acid in tea leaves, has significant anti-stress effects in animals and humans, we examined the effects of green tea with lowered caffeine content, i.e., low-caffeine green tea (LCGT, on stress and quality of sleep of middle–aged individuals (n = 20, mean age 51.3 ± 6.7 years in a double-blind crossover design. Standard green tea (SGT was used as the control. These teas (≥300 mL/day, which were eluted with room temperature water, were consumed over a period of seven days after a single washout term. The level of salivary α-amylase activity (sAA, a stress marker, was significantly lower in participants that consumed LCGT (64.7 U/mL than in those that consumed SGT (73.9 U/mL. Sleep quality was higher in participants that consumed a larger quantity of LCGT. In addition, a self-diagnostic check for accumulated fatigue was significantly lower in those participants that consumed LCGT than SGT. These results indicate that LCGT intake can reduce stress in middle-aged individuals and improve their quality of sleep. The reduction in caffeine is suggested to be a valid reason for enhancing the anti-stress effect of green tea.

  17. A green tea-containing starch confection increases plasma catechins without protecting against postprandial impairments in vascular function in normoglycemic adults.

    Science.gov (United States)

    Sapper, Teryn N; Mah, Eunice; Ahn-Jarvis, Jennifer; McDonald, Joshua D; Chitchumroonchokchai, Chureeporn; Reverri, Elizabeth J; Vodovotz, Yael; Bruno, Richard S

    2016-09-14

    Postprandial hyperglycemia (PPH) increases cardiovascular disease risk regardless of glucose intolerance by transiently impairing vascular endothelial function (VEF) by limiting nitric oxide bioavailability in an oxidative stress-dependent manner. Preclinical studies show that green tea catechins attenuate PPH by inhibiting starch digestion. We hypothesized that a starch-based confection containing catechin-rich green tea extract (GTE) would limit PPH-mediated impairments in VEF in normoglycemic adults. We formulated a unique GTE confection and then conducted a double-blind, randomized, controlled, crossover study in healthy men (n = 15; 25.3 ± 1.0 years; 22.4 ± 1.8 kg m(-2)) in which they ingested starch confections (50 g carbohydrate) formulated with or without GTE (1 g) prior to evaluating sensory characteristics of confections and plasma glucose, biomarkers of lipid peroxidation and nitric oxide homeostasis, and brachial artery flow-mediated dilation (FMD) at 30 min intervals for 3 h. Sensory evaluation of confections indicated acceptable consumer appeal and an inability to distinguish between confections regardless of GTE. Plasma catechins concentrations increased following ingestion of the GTE confection. However, plasma glucose peaked at 60 min (P confection ingestion and was unaffected throughout the postprandial period by the GTE confection (P > 0.05). FMD was significantly decreased only at 60 min regardless of confections containing GTE. Also at 60 min, both confections similarly increased plasma malondialdehyde while decreasing arginine and increasing asymmetric dimethylarginine/arginine. The successfully formulated GTE-containing confection effectively delivered catechins, but without mitigating PPH-mediated impairments in VEF in association with oxidative stress that likely limits nitric oxide bioavailability.

  18. Actual Daily Intakes of Tea Catechins and Thier Estimation According to Four Season 3 Day Weighed Dietary Records and a Short Food Frequency Questionnaire among Japanese Men and Women

    Science.gov (United States)

    Endoh, Kaori; Matsui, Yuji; Takeshita, Masao; Katashima, Mitsuhiro; Yasunaga, Koichi; Kuriki, Kiyonori

    2017-01-01

    Background: Tea catechins are considered to be important preventive factors of cancer on several organs; however, the relationships of the actual daily intakes (ADIs) on the preventive effects have not been adequately addressed. We measured the ADIs of tea catechins as annual averages derived from every their ingested cups recorded by each subject, and the estimation models were established considering tea origin. Methods: Fifty-nine Japanese men and women completed four season 3 day weighed dietary records (WDRs) and a food frequency questionnaire (FFQ), and samples of green, oolong and black teas, ingested during a total 12 days were collected for the analysis. The ADIs of the total and composed catechins of all tea samples were measured by a high-performance liquid chromatography. The estimation models for the ADIs (R2: coefficient of determination) based on the WDRs and FFQ were established with multiple regression analysis using appropriate confounding factors. V Results: The ADIs of total catechins and epigallocatechin gallate (EGCg) were 110 and 21.4 mg/day in men and 157 and 34.7 mg/day in women, respectively. The total catechins ADIs were positively associated with green tea consumption based on WDRs and FFQ (adjusted R2 =0.421 and 0.341 for men and 0.346 and 0.238 for women, p<0.05 for all, respectively). Likewise, the EGCg ADIs were associated with green tea intake derived from WDRs and FFQ, respectively. Conclusions: We revealed the ADIs of total catechins and EGCg as annual averages could establish their estimation models. These provide reference information to clarify their relationships with cancer risks. PMID:29072829

  19. Photoprotective Effect of Tea and its Extracts against Ultraviolet ...

    African Journals Online (AJOL)

    chemopreventive agents in tea include catechins, caffeine, polysaccharides, apigenin and luteolin which inhibit, reverse or retard the ... tumor cellular proteasome inhibitors and apoptosis inducers with potency similar to natural ..... on the effect of chitosan mordanting condition. Fiber. Polym 2006; 7: 255-261. 3 Reinert G ...

  20. Simultaneous determination of caffeine and some selected polyphenols in Wuyi Rock tea by high-performance liquid chromatography.

    Science.gov (United States)

    Zhao, Feng; Lin, He-Tong; Zhang, Shen; Lin, Yi-Fen; Yang, Jiang-Fan; Ye, Nai-Xing

    2014-04-02

    The primary taste and healthy benefits of tea are mainly attributed to tea polyphenols and caffeine. Due to very many kinds of flavonoid glycosides in tea and the lack of commercial standards of flavonoid glycosides, it is critical to develop a rapid and cheap method for determining flavonoid glycosides of tea. Contents of myricetin glycosides and quercetin glycosides in Wuyi Rock tea were determined by detecting contents of corresponding myricetin and quercetin. Optimizing hydrolysis conditions for hydrolyzing flavonoid glycosides to their corresponding flavonols including quercetin and myricetin in Wuyi Rock tea was a key technology for detecting contents of corresponding myricetin and quercetin. The results showed that hydrolysis at 2 mol/L HCl solution and at 90 °C for 1 h was an optimizing condition for hydrolyzing flavonoid glycosides to myricetin and quercetin in Wuyi Rock tea. Caffeine and seven kinds of polyphenols (GA, EGC, C, EGCG, EC, ECG, and CGA) in 20 samples of Wuyi Rock tea were simultaneously determined using a simple and fast reverse-phase high-performance liquid chromatography procedure coupled with photodiode array detector (RP-HPLC-PDAD). The results indicated that there were significant (P < 0.05) differences of ECG, CGA, ECG, and myricetin glycosides in 'Wuyi Rougui' and 'Wuyi Shuixian', which were credited with causing the difference in taste between these two cultivar of Wuyi Rock tea. The study may be useful for clarifying the cause of "cultivated varieties flavor" of Wuyi Rock tea.

  1. A minireview of effects of green tea on energy expenditure.

    Science.gov (United States)

    Türközü, Duygu; Tek, Nilüfer Acar

    2017-01-22

    In recent years, individuals have begun to tend more frequently to some natural and herbal products to be used alone or as a combination with diet and exercise for ensuring the weight loss. Green tea is the leading one of these products. In some studies, it is reported that the green tea causes an increase in thermogenesis and substrate with fat oxidation by affecting on the sympathetic nervous system. It is reported that green tea has two main components that are associated with energy expenditure. One of them is caffeine and the other is catechin content. Each of these two components has an impact on energy mechanism separately. In this minireview article, mechanisms of action and effects of caffeine and catechin, which are found in green tea composition, on energy expenditure are assessed.

  2. A rapid and simple determination of caffeine in teas, coffees and eight beverages.

    Science.gov (United States)

    Sereshti, Hassan; Samadi, Soheila

    2014-09-01

    Caffeine was extracted and preconcentrated by the simple, fast and green method of dispersive liquid-liquid microextraction (DLLME) and analysed by gas chromatography-nitrogen phosphorus detection (GC-NPD). The influence of main parameters affecting the extraction efficiency investigated and optimised. Under the optimal conditions, the method was successfully applied to determination of caffeine in different real samples including five types of tea (green, black, white, oolong teas and tea bag), two kinds of coffee (Nescafe coffee and coffee), and eight beverages (regular Coca Cola, Coca Cola zero, regular Pepsi, Pepsi max, Sprite, 7up, Red Bull and Hype).The limit of detection (LOD) and limit of quantification (LOQ) were 0.02 and 0.05 μg mL(-1), respectively. Linear dynamic range (LDR) was 0.05-500 μg mL(-1) and determination coefficient (R(2)) was 0.9990. The relative standard deviation (RSD) was 3.2% (n=5, C=1 μg mL(-1)). Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Influence of green tea catechins on oxidative stress metabolites at rest and during exercise in healthy humans.

    Science.gov (United States)

    Sugita, Masaaki; Kapoor, Mahendra P; Nishimura, Akinobu; Okubo, Tsutomu

    2016-03-01

    The aim of this study was to investigate the effects of green tea catechins (GTC) on oxidative stress metabolites in healthy individuals while at rest and during exercise. The effects investigated included response to fat metabolism, blood lactate concentrations, and rating of perceived exertion. In a paralleled, crossover, randomized controlled study, 16 trained male gymnastic students were randomly divided into two groups. The rest group (n = 8; GTC-NEX) received a single dose of 780 mg GTC with water but no exercise; the exercise group (n = 8; GTC-EX) received a similar dose of GTC but were instructed to exercise. This was followed by a crossover study with similar exercise regime as a placebo group (PL-EX) that received water only. Blood samples were collected at baseline and after 60 and 120 min of GTC intake. Oxidative stress blood biomarkers using the diacron reactive oxygen metabolite (d-ROMs) and biological antioxidant potential (BAP) tests; urinary 8-hydroxydeoxyguanosine (8-OHdG); 8-OHdG/creatinine; and blood lactate concentrations were analyzed. During the cycle ergometer exercise, volume of maximal oxygen uptake, volume of oxygen consumption, volume of carbon dioxide, and respiratory exchange ratio were measured from a sample of respiratory breath gas collected during low, moderate, and high intensity exercising, and the amount of fat burning and sugar consumption were calculated. Analysis of variance was used to determine statistical significance (P exercise levels after the recovery period. Levels of d-ROMs showed no significant difference from baseline upon GTC intake followed by resting and a resting recovery period in the GTC-NEX group. BAP levels were significant upon GTC intake followed by resting (P = 0.04), and after a resting recovery period (P = 0.0006) in the GTC-NEX group. Urinary 8-OHdG levels were significant (P exercise-induced BAP to d-ROMs (P = 0.022) after 60 min of GTC intake, as well as resting 8-OHdG and exercise-induced 8-OHd

  4. The effect of coffee, tea, and caffeine consumption on serum uric acid and the risk of hyperuricemia in Korean Multi-Rural Communities Cohort.

    Science.gov (United States)

    Bae, Jisuk; Park, Pil Sook; Chun, Byung-Yeol; Choi, Bo Youl; Kim, Mi Kyung; Shin, Min-Ho; Lee, Young-Hoon; Shin, Dong Hoon; Kim, Seong-Kyu

    2015-02-01

    Caffeine, a commonly consumed food constituent, is known to exert beneficial physiological effects in humans. There is a lack of comprehensive population data for the effects of caffeine intake on urate metabolism. Therefore, the aim of this study was to determine whether coffee, tea, and caffeine intake influences serum uric acid and the risk of hyperuricemia in the Korean Multi-Rural Communities Cohort. We enrolled 9,400 participants in this study. An assessment of various dietary intake amounts of substances such as coffee and tea was performed using a food frequency questionnaire. The content of caffeine was calculated from coffee (74 mg/cup) and tea (15 mg/cup) intake information from the past year. Multivariate logistic regression models, multiple linear regression models, and analysis of covariance were applied to identify any association of dietary intake with serum uric acid levels or the risk of hyperuricemia. No trends for coffee, tea, or caffeine intake were found according to each quintile with serum uric acid in males, although there were weak, marginally significant trends between the content of coffee and caffeine intake and serum uric acid level in females (p = 0.07 for both). Tea intake in males and caffeine intake in females were significantly different between non-hyperuricemia and hyperuricemia (p = 0.04 and p = 0.04, respectively). In addition, a significant association of serum uric acid level with tea intake in males (β = 0.0006, p = 0.02) and with tea intake and caffeine intake in females (β = 0.0003, p = 0.04 and β = 0.0006, p = 0.02, respectively) was observed. There was no effect of coffee, tea, or caffeine intake on the risk of hyperuricemia in either males or females. This study suggests that caffeine consumption might have an effect on serum uric acid in females. However, coffee, tea, and caffeine intake amounts were not associated with the risk of hyperuricemia.

  5. Tea, coffee, and caffeine and early-onset basal cell carcinoma in a case-control study.

    Science.gov (United States)

    Ferrucci, Leah M; Cartmel, Brenda; Molinaro, Annette M; Leffell, David J; Bale, Allen E; Mayne, Susan T

    2014-07-01

    Tea and coffee are hypothesized to play a protective role in skin carcinogenesis through bioactive components, such as caffeine, yet the epidemiologic evidence is mixed. Existing data support an inverse association with basal cell carcinoma (BCC), more so than for melanoma or squamous cell carcinoma. To understand whether tea, coffee, and caffeine are related to early-onset BCC, we evaluated data from 767 non-Hispanic Whites under age 40 in a case-control study in Connecticut. BCC cases (n=377) were identified through Yale's Dermatopathology database. Controls (n=390) were randomly sampled from individuals in the same database with benign skin diagnoses and frequency matched to cases on age, sex, and biopsy site. Participants completed an in-person interview including assessment of caffeinated coffee and hot tea. We calculated multivariate odds ratios (ORs) and 95% confidence intervals (CIs) with unconditional logistic regression for regular consumption and frequency and duration measures. Combined regular consumption of caffeinated coffee plus hot tea was inversely associated with early-onset BCC (OR=0.60, 95% CI=0.38-0.96). Those in the highest category of caffeine from these sources had a 43% reduced risk of BCC compared with nonconsumers (OR=0.57, 95% CI=0.34-0.95, P-trend=0.037). Our findings suggest a modest protective effect for caffeinated coffee plus tea in relation to early-onset BCC that may, in part, be due to caffeine. This study adds to the growing body of literature suggesting potential health benefits from these beverages.

  6. Effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites in rats

    OpenAIRE

    Wu, Tao; Wu, Ji; Gao, Ping; Xiang, Daochun; Liu, Dong; Song, Hongping

    2015-01-01

    abstract The aim of this study was to evaluate the effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites. Rats were intragastrically administered caffeine (30 mg·kg-1, once per day), tea polyphenol (400 mg·kg-1, once per day) or daidzein (13.5 mg·kg-1, once per day) for 14 days, followed by an intragastric administration of lansoprazole (8 mg·kg-1) on the 15th day. The plasma concentrations of lansoprazole and its two primary metabolites,...

  7. Smoking, alcohol, coffee, tea, caffeine, and theobromine: risk of prostate cancer in Utah (United States).

    Science.gov (United States)

    Slattery, M L; West, D W

    1993-11-01

    Data from a population-based study of newly diagnosed cases of prostate cancer (n = 362) and age-matched controls (n = 685) conducted in Utah (United States) between 1983 and 1986 were used to determine if cigarette smoking, alcohol, coffee, tea, caffeine, and theobromine were associated with prostate cancer risk. These factors were examined since their use differs in the Utah population, which is comprised predominantly of members of the Church of Jesus Christ of Latter-day Saints (LDS or Mormon), from most other populations. Pack-years of cigarettes smoked, alcohol intake, and consumption of alcohol, coffee, tea, and caffeine were not associated with prostate cancer risk. Compared with men with very low levels of theobromine intake, older men consuming 11 to 20 and over 20 mg of theobromine per day were at increased risk of prostate cancer (odds ratio [OR] for all tumors = 2.06, 95 percent confidence interval [CI] = 1.33-3.20, and OR = 1.47, CI = 0.99-2.19, respectively; OR for aggressive tumors = 1.90, CI = 0.90-3.97, and OR = 1.74, CI = 0.91-3.32, respectively). We present biological mechanisms for a possible association between prostate cancer and theobromine. This finding needs further exploration in studies with a wider range of theobromine exposures and more men with aggressive tumors.

  8. Coffee, tea, caffeine and risk of depression: A systematic review and dose-response meta-analysis of observational studies.

    Science.gov (United States)

    Grosso, Giuseppe; Micek, Agnieszka; Castellano, Sabrina; Pajak, Andzrej; Galvano, Fabio

    2016-01-01

    The aim of the study was to systematically review and analyze results from observational studies on coffee, caffeine, and tea consumption and association or risk of depression. Embase and PubMed databases were searched from inception to June 2015 for observational studies reporting the odds ratios or relative risks (RRs) and 95% confidence intervals (CI) of depression by coffee/tea/caffeine consumption. Random effects models, subgroup analyses, and dose-response analyses were performed. Twelve studies with 23 datasets were included in the meta-analysis, accounting for a total of 346 913 individuals and 8146 cases of depression. Compared to individuals with lower coffee consumption, those with higher intakes had pooled RR of depression of 0.76 (95% CI: 0.64, 0.91). Dose-response effect suggests a nonlinear J-shaped relation between coffee consumption and risk of depression with a peak of protective effect for 400 mL/day. A borderline nonsignificant association between tea consumption and risk of depression was found (RR 0.70, 95% CI: 0.48, 1.01), while significant results were found only for analysis of prospective studies regarding caffeine consumption (RR = 0.84, 95% CI: 0.75, 0.93). This study suggests a protective effect of coffee and, partially, of tea and caffeine on risk of depression. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Habitual coffee and tea drinkers experienced increases in blood pressure after consuming low to moderate doses of caffeine; these increases were larger upright than in the supine posture.

    Science.gov (United States)

    McMullen, Michael K; Whitehouse, Julie M; Shine, Gillian; Towell, Anthony

    2011-04-01

    Caffeine users have been encouraged to consume caffeine regularly to maintain their caffeine tolerance and so avoid caffeine's acute pressor effects. In controlled conditions complete caffeine tolerance to intervention doses of 250 mg develops rapidly following several days of caffeine ingestion, nevertheless, complete tolerance is not evident for lower intervention doses. Similarly complete caffeine tolerance to 250 mg intervention doses has been demonstrated in habitual coffee and tea drinkers' but for lower intervention doses complete tolerance is not evident. This study investigated a group of habitual caffeine users following their self-determined consumption pattern involving two to six servings daily. Cardiovascular responses following the ingestion of low to moderate amounts caffeine (67, 133 and 200 mg) were compared with placebo in a double-blind, randomised design without caffeine abstinence. Pre-intervention and post-intervention (30 and 60 min) 90 s continuous cardiovascular recordings were obtained with the Finometer in both the supine and upright postures. Participants were 12 healthy habitual coffee and tea drinkers (10 female, mean age 36). Doses of 67 and 133 mg increased systolic pressure in both postures while in the upright posture diastolic pressure and aortic impedance increased while arterial compliance decreased. These vascular changes were larger upright than supine for 133 mg caffeine. Additionally 67 mg caffeine increased dp/dt and indexed peripheral resistance in the upright posture. For 200 mg caffeine there was complete caffeine tolerance. Cardiovascular responses to caffeine appear to be associated with the size of the intervention dose. Habitual tea and coffee drinking does not generate complete tolerance to caffeine as has been previously suggested. Both the type and the extent of caffeine induced cardiovascular changes were influenced by posture.

  10. Production, Composition, and Health Effects of Oolong Tea

    Directory of Open Access Journals (Sweden)

    İlkay Koca

    2014-03-01

    Full Text Available Tea, one of the most widely consumed beverages in the world, is produced from the leaves of the plant Camellia sinensis L.. Tea has important physiological properties and potential health benefits due to the presence of compounds such as polyphenols, amino acids, vitamins, carbohydrates, caffeine, and purine alkaloids. Tea is produced in three types as green tea (unfermented, oolong tea (partially fermented, and black tea (fully fermented. Black tea is consumed worldwide, whereas green and oolong teas are consumed mainly in Asia and North Africa. The total tea production in the world consists of about 78% black tea, 20% green tea and <2% oolong tea. In the production of green tea, the fresh leaves are steamed or roasted to avoid enzymatic oxidation. Black tea is fully oxidized during fermentation. Oolong tea is partially fermented to permit a moderate level of enzymatic oxidation during processing. The degree of fermentation of oolong tea leaves ranges from 20 to 60%, depending upon consumer demand. Oolong tea has a taste and color somewhere between green and black tea. Green tea contains 30-42% catechins in dry mass, while black tea contains 3-10% and oolong 8-20%. Oolong tea has a higher antioxidant activity and lipoxygenase inhibitory activity as compared to black tea. Oolong tea exhibits a stronger antimutagenic activity than green or black tea. Oolong tea is reported to have anticancer, antiobesity, antidiabetes, antiallergic effects, and prevent atherosclerosis and heart disease. In this review, the production, composition and health effects of oolong tea have been discussed.

  11. Dose-response meta-analysis on coffee, tea and caffeine consumption with risk of Parkinson's disease.

    Science.gov (United States)

    Qi, Hui; Li, Shixue

    2014-04-01

    A dose-response meta-analysis was carried out between Parkinson's disease (PD) risk, and coffee, tea and caffeine consumption. A comprehensive search was carried out to identify eligible studies. The fixed or random effect model was used based on heterogeneity test. The dose-response relationship was assessed by restricted cubic spline. A total of 13 articles involving 901 764 participants for coffee, eight articles involving 344 895 participants for tea and seven articles involving 492 724 participants for caffeine were included. A non-linear relationship was found between coffee consumption and PD risk overall, and the strength of protection reached the maximum at approximately 3 cups/day (smoking-adjusted relative risk: 0.72, 95% confidence interval 0.65-0.81). A linear relationship was found between tea and caffeine consumption, and PD risk overall, and the smoking-adjusted risk of PD decreased by 26% and 17% for every two cups/day and 200 mg/day increments, respectively. The association of coffee and tea consumption with PD risk was stronger for men than that for women, and the association of caffeine consumption with PD risk was stronger for ever users of hormones than that for never users of hormones among postmenopausal women. The aforementioned associations were weaker for USA relative to Europe or Asia. A linear dose-relationship for decreased PD risk with tea and caffeine consumption was found, whereas the strength of protection reached a maximum at approximately 3 cups/day for coffee consumption overall. Further studies are required to confirm the findings. © 2013 Japan Geriatrics Society.

  12. Antioxidative capacity and binding affinity of the complex of green tea catechin and beta-lactoglobulin glycated by the Maillard reaction.

    Science.gov (United States)

    Perusko, Marija; Al-Hanish, Ayah; Mihailovic, Jelena; Minic, Simeon; Trifunovic, Sara; Prodic, Ivana; Cirkovic Velickovic, Tanja

    2017-10-01

    Major green tea catechin, epigallocatechin-3-gallate (EGCG), binds non-covalently to numerous dietary proteins, including beta-lactoglobulin of cow's milk. The effects of glycation of proteins via Maillard reaction on the binding capacity for polyphenols and the antiradical properties of the formed complexes have not been studied previously. Binding constant of BLG glycated by milk sugar lactose to EGCG was measured by the method of fluorophore quenching. Binding of EGCG was confirmed by CD and FTIR. The antioxidative properties of the complexes were examined by measuring ABTS radical scavenging capacity, superoxide anion scavenging capacity and total reducing power assay. Glycation of BLG does not significantly influence the binding constant of EGCG for the protein. Conformational changes were observed for both native and glycated BLG upon complexation with EGCG. Masking effect of polyphenol complexation on the antioxidative potential of the protein was of the similar degree for both glycated BLG and native BLG. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Occurrence of Functional Molecules in the Flowers of Tea (Camellia sinensis) Plants: Evidence for a Second Resource.

    Science.gov (United States)

    Chen, Yiyong; Zhou, Ying; Zeng, Lanting; Dong, Fang; Tu, Youying; Yang, Ziyin

    2018-03-29

    Tea ( Camellia sinensis ) is an important crop, and its leaves are used to make the most widely consumed beverage, aside from water. People have been using leaves from tea plants to make teas for a long time. However, less attention has been paid to the flowers of tea plants, which is a waste of an abundant resource. In the past 15 years, researchers have attempted to discover, identify, and evaluate functional molecules from tea flowers, and have made insightful and useful discoveries. Here, we summarize the recent investigations into these functional molecules in tea flowers, including functional molecules similar to those in tea leaves, as well as the preponderant functional molecules in tea flowers. Tea flowers contain representative metabolites similar to those of tea leaves, such as catechins, flavonols, caffeine, and amino acids. The preponderant functional molecules in tea flowers include saponins, polysaccharides, aromatic compounds, spermidine derivatives, and functional proteins. We also review the safety and biological functions of tea flowers. Tea flower extracts are proposed to be of no toxicological concern based on evidence from the evaluation of mutagenicity, and acute and subchronic toxicity in rats. The presence of many functional metabolites in tea flowers indicates that tea flowers possess diverse biological functions, which are mostly related to catechins, polysaccharides, and saponins. Finally, we discuss the potential for, and challenges facing, future applications of tea flowers as a second resource from tea plants.

  14. Stimulatory effect of oral administration of tea, coffee or caffeine on UVB-induced apoptosis in the epidermis of SKH-1 mice

    International Nuclear Information System (INIS)

    Conney, Allan H.; Zhou, Sherry; Lee Maojung; Xie Jianguo; Yang, Chung S.; Lou Yourong; Lu Yaoping

    2007-01-01

    Oral administration of green tea or a caffeine solution, but not decaffeinated green tea, inhibits UVB-induced complete carcinogenesis in SKH-1 mice. Oral administration of green tea, coffee or a caffeine solution for 2 weeks enhanced UVB-induced increases in apoptosis in the epidermis, but these treatments had no effect in non-UVB treated normal epidermis. Our results suggest that administration of green tea, coffee and caffeine may inhibit UVB-induced carcinogenesis - at least in part - by enhancing UVB-induced apoptosis. Plasma levels of caffeine observed after its oral administration at cancer-preventive dose levels were within the range observed in moderate coffee drinkers. Topical applications of caffeine to mice previously treated with UVB for 20 weeks (high risk mice without tumors) inhibited the formation of tumors and stimulated apoptosis in the tumors but not in areas of the epidermis away from tumors. The selective effects of caffeine administration to stimulate UVB-induced apoptosis or apoptosis in tumors but not in normal epidermis or in areas of the epidermis away from tumors is of considerable interest, but the reasons for the selective effects of caffeine on apoptosis in DNA damaged tissues are unknown. Further studies are needed to determine mechanisms of these effects of caffeine and to determine the effects of caffeine administration on sunlight-induced actinic keratoses and squamous cell carcinomas in humans

  15. Maternal caffeine consumption from coffee and tea during pregnancy and behavioural disorders in 11-year-old offspring; a Danish national birth cohort study

    DEFF Research Database (Denmark)

    Mikkelsen, Susanne Hvolgaard; Obel, Carsten; Olsen, Jørn

    2017-01-01

    Objective: To examine the association between maternal caffeine consumption from coffee and tea during pregnancy and offspring behavioural disorders. Methods: We studied 47491 children enrolled in the Danish National Birth Cohort between 1996-2002. Data on maternal coffee and tea consumption...... with increasing daily caffeine consumption at 15 weeks of gestation. Conclusion: High maternal caffeine consumption from coffee and tea at 15 weeks of gestation was associated with behavioural disorders in 11-year old offspring. The hypothesis that caffeine exposure may affect the foetal brain and program...... for behavioural disorders later in life cannot be rejected. The foetal brain seems to be more sensitive to caffeine exposure at 15 weeks of pregnancy compared to 30 weeks of gestation....

  16. Coffee, tea, and caffeine consumption and prevention of late-life cognitive decline and dementia: a systematic review.

    Science.gov (United States)

    Panza, F; Solfrizzi, V; Barulli, M R; Bonfiglio, C; Guerra, V; Osella, A; Seripa, D; Sabbà, C; Pilotto, A; Logroscino, G

    2015-03-01

    A prolonged preclinical phase of more than two decades before the onset of dementia suggested that initial brain changes of Alzheimer's disease (AD) and the symptoms of advanced AD may represent a unique continuum. Given the very limited therapeutic value of drugs currently used in the treatment of AD and dementia, preventing or postponing the onset of AD and delaying or slowing its progression are becoming mandatory. Among possible reversible risk factors of dementia and AD, vascular, metabolic, and lifestyle-related factors were associated with the development of dementia and late-life cognitive disorders, opening new avenues for the prevention of these diseases. Among diet-associated factors, coffee is regularly consumed by millions of people around the world and owing to its caffeine content, it is the best known psychoactive stimulant resulting in heightened alertness and arousal and improvement of cognitive performance. Besides its short-term effect, some case-control and cross-sectional and longitudinal population-based studies evaluated the long-term effects on brain function and provided some evidence that coffee, tea, and caffeine consumption or higher plasma caffeine levels may be protective against cognitive impairment/decline and dementia. In particular, several cross-sectional and longitudinal population-based studies suggested a protective effect of coffee, tea, and caffeine use against late-life cognitive impairment/decline, although the association was not found in all cognitive domains investigated and there was a lack of a distinct dose-response association, with a stronger effect among women than men. The findings on the association of coffee, tea, and caffeine consumption or plasma caffeine levels with incident mild cognitive impairment and its progression to dementia were too limited to draw any conclusion. Furthermore, for dementia and AD prevention, some studies with baseline examination in midlife pointed to a lack of association, although

  17. Caffeine

    Science.gov (United States)

    ... the jitters. Caffeine can also interfere with normal sleep. Caffeine sensitivity (the amount of caffeine that will produce ... As you cut back on the amount of caffeine you consume, you may find yourself feeling tired. Be sure you're getting enough sleep and boost your energy by exercising. As your ...

  18. Effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites in rats

    Directory of Open Access Journals (Sweden)

    Tao Wu

    2015-12-01

    Full Text Available abstract The aim of this study was to evaluate the effects of caffeine, tea polyphenol and daidzein on the pharmacokinetics of lansoprazole and its metabolites. Rats were intragastrically administered caffeine (30 mg·kg-1, once per day, tea polyphenol (400 mg·kg-1, once per day or daidzein (13.5 mg·kg-1, once per day for 14 days, followed by an intragastric administration of lansoprazole (8 mg·kg-1 on the 15th day. The plasma concentrations of lansoprazole and its two primary metabolites, 5-hydroxylansoprazole and lansoprazole sulfone, were determined by high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS. Tea polyphenol significantly elevated the Area Under the Curve (AUC of lansoprazole from 680.29 ± 285.99 to 949.76 ± 155.18 μg/L.h and reduced that of lansoprazole sulfone from 268.82 ± 82.37 to 177.72 ± 29.73 μg/L.h. Daidzein increased the AUC of lansoprazole from 680.29 ± 285.99 to 1130.44 ± 97.6 μg/L.h and decreased that of lansoprazole sulfone from 268.82 ± 82.37 to 116.23 ± 40.14 μg/L.h. The pharmacokinetics of 5-hydroxylansoprazole remained intact in the presence of tea polyphenol or daidzein. Caffeine did not affect the pharmacokinetics of lansoprazole and its metabolites. The results imply that tea polyphenol and daidzein may inhibit the in vivo metabolism of lansoprazole by suppressing CYP3A.

  19. Quantitative Analysis of Major Phytochemicals in Orthodox tea (Camellia sinensis), Oxidized under Compressed Air Environment.

    Science.gov (United States)

    Panda, Brajesh Kumar; Datta, Ashis Kumar

    2016-04-01

    This study describes major changes in phytochemical composition of orthodox tea (Camellia sinensis var. Assamica) oxidized under compressed air (CA). The experiments for oxidation were conducted under air pressure (101, 202, and 303 kPa) for 150 min. Relative change in the concentrations of caffeine, catechins, theaflavins (TF), and thearubigins (TR) were analyzed. Effect of CA pressure was found to be nonsignificant in regulating caffeine concentration during oxidation. But degradation in different catechins as well as formation of different TF was significantly affected by CA pressure. At high CA pressure, TF showed highest peak value. TR was found to have slower rate of formation during initial phase of oxidation than TF. Even though the rate of TR formation was significantly influenced by CA, a portion of catechins remained unoxidized at end of oxidation. Except caffeine, the percent change in rate of formation or degradation were more prominent at 202 kPa. © 2016 Institute of Food Technologists®

  20. Caffein

    DEFF Research Database (Denmark)

    Nørager, Charlotte Buchard; Jensen, Martin Bach; Madsen, Mogens Rørbæk

    2005-01-01

    Summary Caffeine: physiological and pharmacologic aspects Ugeskr Læger 2004;166:2138-2142 Caffeine is the most widely used stimulant in the world. This is due not only to the fact that it is found in a great number of food products and is therefore readily available, but also because caffeine...... intake results in such positive effects as elation, pleasantness and better reactivity and because abstinence from caffeine can result in a withdrawal syndrome including headache, tiredness, restlessness and heart palpitations. Caffeine is also used in sports, as caffeine in moderate doses (3-6 mg....../kg) can increase the endurance of athletes engaged in running, bicycling, swimming and other endurance sports. Caffeine is used both in training and in competitions, and the International Olympic Commitée (IOC) has included caffeine as a drug used for doping. There are several theories about caffeine...

  1. Maternal total caffeine intake, mainly from Japanese and Chinese tea, during pregnancy was associated with risk of preterm birth: the Osaka Maternal and Child Health Study.

    Science.gov (United States)

    Okubo, Hitomi; Miyake, Yoshihiro; Tanaka, Keiko; Sasaki, Satoshi; Hirota, Yoshio

    2015-04-01

    The relation of maternal caffeine intake with birth outcomes is still inconclusive and has not been examined in Japan, where the sources of caffeine intake are different from those in Western countries. We hypothesized that maternal consumption of total caffeine and culture-specific major sources of caffeine would be associated with birth outcomes among Japanese pregnant. The study subjects were 858 Japanese women who delivered singleton infants. Maternal diet during pregnancy was assessed using a validated, self-administered diet history questionnaire. Birth outcomes considered were low birth weight (LBW; caffeine sources were Japanese and Chinese tea (73.5%), coffee (14.3%), black tea (6.6%), and soft drinks (3.5%). After controlling for confounders, maternal total caffeine intake during pregnancy was significantly associated with an increased risk of PTB (odds ratio per 100 mg/d caffeine increase, 1.28; 95% confidence interval, 1.03-1.58; P for trend = .03). However, no evident relationships were observed between total caffeine intake and risk of LBW or SGA. As for caffeine sources, higher Japanese and Chinese tea consumption was associated with an increased risk of PTB (odds ratio per 1 cup/d increase, 1.14; 95% confidence interval, 1.00-1.30; P for trend = .04), but not LBW or SGA. There were no associations between consumption of the other beverages examined and birth outcomes. In conclusion, this prospective birth cohort in Japan suggests that higher maternal total caffeine intake, mainly in the form of Japanese and Chinese tea, during pregnancy is associated with a greater risk of PTB. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. Effects of stachyose on absorption and transportation of tea catechins in mice: possible role of Phase II metabolic enzymes and efflux transporters inhibition by stachyose.

    Science.gov (United States)

    Li, Wenfeng; Lu, Yalong; Huang, Di; Han, Xiao; Yang, Xingbin

    2016-01-01

    Nutritional and absorption-promoting properties of stachyose combined with tea catechins (TC) have been revealed. However, the mechanism involved in non-digestible oligosaccharides-mediated enhancement of flavonoid absorption has largely remained elusive. This study was designed to investigate the molecular mechanism of stachyose in enhancing absorption and transportation of TC in mice. Mice were orally pre-treated with stachyose (50, 250, and 500 mg/kg·bw) for 0-8 weeks, and 1 h before sacrifice, mice were treated with TC (250 mg/kg·bw). Gas chromatography-mass spectrometry analysis showed that serum concentrations of epicatechin, epigallocatechin, epicatechin gallate, and epigallocatechin gallate were dose- and time-dependently elevated with stachyose pre-treatment in mice. Furthermore, pre-treatment with stachyose in mice reduced intestinal sulfotransferase and uridine diphosphate-glucuronosyltransferase levels by 3.3-43.2% and 23.9-30.4%, relative to control mice, respectively. Moreover, intestinal P-glycoprotein and multidrug resistance-associated protein-1 contents were decreased in mice by pre-administration of stachyose in dose- and time-dependent manner. This is the first time to demonstrate that suppression of Phase II metabolic enzymes and efflux transporters of TC in the intestine can play a major role in increasing absorption of TC by stachyose feeding.

  3. The Effect of Dietary Supplementation of Green Tea Catechins on Cardiovascular Disease Risk Markers in Humans: A Systematic Review of Clinical Trials

    Directory of Open Access Journals (Sweden)

    Sarah O. Lau

    2016-06-01

    Full Text Available Green tea catechins (GTCs are secondary plant metabolites that have been associated with health benefits in human trials. As such, they have the potential to reduce cardiovascular disease (CVD risk; however, results are not consistent. This systematic review of the published data assessed the putative effect of GTCs supplementation on anthropometric, blood pressure, and biochemical measures associated with CVD risk. It was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA guidelines exploring four major electronic databases (MEDLINE, Cochrane Library, Web of Science, and Scopus. Studies were included if they were published in peer-reviewed journals in English from 1990 until October 2015, and were human double-blind randomized and placebo-controlled trials (RCTs. From 122,428 articles initially identified, after two levels of screening, seven studies met the inclusion criteria. The review revealed consistent and significant (p ≤ 0.05 reductions in body mass index (BMI, blood pressure and plasma lipids; however, this effect would have been less if between-group effects had been considered. The current evidence base also has considerable methodological limitations due to suboptimal statistical methods used in data analyses. Future research efforts must aim to rectify this paucity of evidence with well-designed and well-reported prospective studies.

  4. Simultaneous determination of 15 phenolic compounds and caffeine in teas and mate using RP-HPLC/UV detection: method development and optimization of extraction process.

    Science.gov (United States)

    Bae, In Kyung; Ham, Hyeon Mi; Jeong, Min Hee; Kim, Dong Ho; Kim, Ho Jin

    2015-04-01

    A reversed-phase high performance liquid chromatographic coupled to ultraviolet detection (RP-HPLC/UV) method was developed for simultaneous determination of 15 phenolic compounds and caffeine in TEAS (green tea, oolong tea, black tea and mate). Furthermore, the extraction process of total phenolic contents (TPC) from TEAS were optimized using response surface methodology (RSM) based on a central composite design (CCD) and then applied to extraction of TEAS. The best conditions obtained using the model were as follow: green tea--extraction time of 123 min, extraction temperature of 70 °C and ethanol concentration of 75%, oolong tea--extraction time of 98 min, extraction temperature of 70 °C and ethanol concentration of 69%, black tea--extraction time of 105 min, extraction temperature of 71 °C and ethanol concentration of 63%, and mate--extraction time of 103 min, extraction temperature of 71 °C and ethanol concentration of 61%. Among the extraction methods used in this study, heat-reflux extraction was found to result in the highest values of TPC. The chromatographic peaks of the 16 studied compounds were successfully identified by comparing their retention time and UV spectra with the reference standards. Method validation was performed by means of linearity, sensitivity, selectivity, accuracy and precision. The developed method was found to be simple, specific and reliable and is suited for routine analysis of phenolic compounds and caffeine in TEAS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Pharmacokinetic interaction of green tea beverage containing cyclodextrins and high concentration catechins with P-glycoprotein substrates in LLC-GA5-COL150 cells in vitro and in the small intestine of rats in vivo.

    Science.gov (United States)

    Oda, Keisuke; Murakami, Teruo

    2017-12-01

    Possible interaction of green tea beverage (GT) containing cyclodextrins and high concentration catechins, a drinking water, with P-glycoprotein (P-gp) substrates was examined in vitro and in vivo. Effects of GT on the uptake of rhodamine 123 by LLC-GA5-COL150 cells and intestinal efflux of rhodamine 123 from blood, intestinal absorption of quinidine from ileum loop and oral absorption of digoxin were examined in rats. Effects of GT and GT components on digoxin solubility were also examined. Green tea increased the uptake of rhodamine 123 by LLC-GA5-COL150 cells, suppressed the intestinal efflux of rhodamine 123 from blood and increased the absorption of quinidine in the ileum of rats. Also, GT increased the solubility of digoxin, and ingestion of GT significantly increased the oral absorption of digoxin given at a high dose in rats. Green tea suppressed the P-gp-mediated efflux transport of hydrophilic compounds and increased the solubility of lipophilic compounds. Thus, GT may cause interaction with various P-gp substrates, due to the combined effects of catechins and cyclodextrins. Especially, cyclodextrin alone can cause interaction with various low-solubility compounds in vivo. In taking low-solubility drugs including low-solubility P-gp substrates, cyclodextrin-containing foods and beverages such as GT should be avoided. © 2017 Royal Pharmaceutical Society.

  6. Development of a methodology using gas chromatography-combustion-isotope ratio mass spectrometry for the determination of the carbon isotope ratio of caffeine extracted from tea leaves (Camellia sinensis).

    Science.gov (United States)

    Wu, Chen; Yamada, Keita; Sumikawa, Osamu; Matsunaga, Akiko; Gilbert, Alexis; Yoshida, Naohiro

    2012-04-30

    Compound-specific isotope analysis (CSIA) of the extracted caffeine can be used to determine the authenticity of the origin of tea. Elemental analysis-isotope ratio mass spectrometry (EA-IRMS), which is widely used to measure the carbon isotope ratio of caffeine, has a strict requirement for the purity of the extracted caffeine. To obtain high-purity caffeine from tea leaves, the conventional extraction process has to be repeated and usually takes about 5-6 h. To improve the measurement of the carbon isotope ratio of caffeine, a more rapid and accurate measuring method is needed. An analytical protocol was developed for the determination of the carbon isotope ratio of caffeine from tea leaves using gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) combined with our extraction process. The procedure to extract caffeine and determine its carbon isotope ratio takes around 1.5 h. The standard deviation of the method is less than 0.1‰ (1σ). The measured carbon isotope ratios were not influenced by the amount of caffeine injected (0.08-0.62 µg) or by the extraction yield of caffeine from the tea leaves. The carbon isotope ratios of caffeine from eight tea cultivars were determined using the protocol. Copyright © 2012 John Wiley & Sons, Ltd.

  7. Dietary catechins and cancer incidence among postmenopausal women: the Iowa Women's Health Study (US)

    NARCIS (Netherlands)

    Arts, I.C.W.; Jacobs Jr., D.R.; Gross, M.; Harnack, L.J.; Folsom, A.R.

    2002-01-01

    Catechins are bioactive flavonoids present in tea, fruits, and vegetables. Previous epidemiological studies regarding tea and cancer risk were inconclusive, possibly because catechins are also present in other plant foods. We investigated whether a high intake of catechins are associated with cancer

  8. PLE in the analysis of plant compounds. Part I. The application of PLE for HPLC analysis of caffeine in green tea leaves.

    Science.gov (United States)

    Dawidowicz, Andrzej L; Wianowska, Dorota

    2005-04-29

    A broad spectrum of sample preparation methods is currently used for the isolation of pharmacologically active compounds from plant and herbal materials. The paper compares the effectiveness of infusion, microwave assisted solvent extraction (MASE), matrix solid-phase dispersion (MSPD) and pressurised liquid extraction (PLE) as sample preparation methods for the isolation of caffeine from green tea leaves. The effect of PLE variables, such as extraction temperature, pressure and time, on the yield of caffeine from the investigated matrix is discussed. The obtained results revealed that PLE, in comparison with other sample preparation methods applied, has significantly lower efficacy for caffeine isolation from green tea leaves. The evaluation of PLE conditions leads to the conclusion that elevated pressure applied in the PLE process is the factor hindering the extraction.

  9. Influence of brewing conditions on taste components in Fuding white tea infusions.

    Science.gov (United States)

    Zhang, Haihua; Li, Yulin; Lv, Yangjun; Jiang, Yulan; Pan, Junxian; Duan, Yuwei; Zhu, Yuejin; Zhang, Shikang

    2017-07-01

    White tea has received increasing attention of late as a result of its sweet taste and health benefits. During the brewing of white tea, many factors may affect the nutritional and sensory quality of the resulting infusions. The present study aimed to investigate the effect of various infusion conditions on the taste components of Fuding white tea, including infusion time, ratio of tea and water, number of brewing steps, and temperature. Brewing conditions had a strong effect on the taste compound profile and sensory characteristics. The catechin, caffeine, theanine and free amino acid contents generally increased with increasing infusion time and temperature. Conditions comprising an infusion time of 7 min, a brewing temperature of 100 °C, a tea and water ratio of 1:30 or 1:40, and a second brewing step, respectively, were shown to obtain the highest contents of most compounds. Regarding tea sensory evaluation, conditions comprising an infusion time of 3 min, a brewing temperature of 100 °C, a tea and water ratio of 1:50, and a first brewing step, resulted in the highest sensory score for comprehensive behavior of color, aroma and taste. The results of the present study reveal differences in the contents of various taste compounds, including catechins, caffeine, theanine and free amino acids, with respect to different brewing conditions, and sensory scores also varied with brewing conditions. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  10. Quantitative Analysis of Major Constituents in Green Tea with Different Plucking Periods and Their Antioxidant Activity

    Directory of Open Access Journals (Sweden)

    Lan-Sook Lee

    2014-07-01

    Full Text Available The objective of this study was to determine the relationship between the plucking periods and the major constituents and the antioxidant activity in green tea. Green tea was prepared from leaves plucked from the end of April 2013 to the end of May 2013 at intervals of one week or longer. The contents of theanine, theobromine, caffeine, catechin (C, and gallocatechin gallate (GCg were significantly decreased, whereas those of epicatechin (EC, epigallocatechin gallate (EGCg and epigallocatechin (EGC were significantly increased along with the period of tea leaf plucking. In addition, antioxidant activity of green tea and standard catechins was investigated using ABTS, FRAP and DPPH assays. The highest antioxidant activity was observed in relatively the oldest leaf, regardless of the assay methods used. Additionally, the order of antioxidant activity of standard catechins was as follows: EGCg ³ GCg ³ ECg > EGC ³ GC ³ EC ³ C. Moreover, the cis-catechins contents were the key factor affecting the antioxidant activity of green tea in all assays employed (ABTS, r = 0.731, p < 0.01; FRAP, r = 0.886, p < 0.01; DPPH, r = 0.778, p < 0.01.

  11. Analysis of cream formation in green tea concentrates with different solid concentrations.

    Science.gov (United States)

    Xu, Yong-Quan; Chen, Su-Qin; Yuan, Hai-Bo; Tang, Ping; Yin, Jun-Feng

    2012-06-01

    The formation of tea cream in the green tea concentrates of different solid concentrations (5, 10, 20, 30, 40, 50 and 60°Brix) was investigated. The results showed a good positive correlation (γ = 0.98, p ≤ 0.05) between the amount of tea cream and the solid concentrations from 5 to 40°Brix, while the amount of tea cream in the tea concentrates of 50 and 60°Brix decreased acutely. Total sugar, caffeine and catechins were found to be the main chemical components of tea cream in the green tea concentrate. The large decrease of the amount of tea cream in the tea concentrates of 50 and 60°Brix may be induced by a sharp increase of the viscosity of the tea concentrates, which helped to improve the stability of tea concentrate. It may be indicated that the stability of green tea concentrate enhanced when the concentration higher than 50°Brix, which helped to restrain the formation of tea cream.

  12. Xanthine-Catechin Mixture Enhances Lithium-Induced Anti-Inflammatory Response in Activated Macrophages In Vitro

    Directory of Open Access Journals (Sweden)

    Fernanda Barbisan

    2017-01-01

    Full Text Available Lithium (Li is a chemical element used for treating and preventing bipolar disorder (BD and exerts positive effects such as anti-inflammatory effects as well as undesirable side effects. These effects of Li can be influenced by interaction with some nutritional elements. Therefore, we investigated the potential effects of xanthine (caffeine and theobromine and catechin molecules present in some food beverages broadly consumed worldwide, such as coffee and tea, on Li-induced anti-inflammatory effects. In the present study, we concomitantly exposed RAW 264.7 macrophages to Li, isolated xanthine and catechin molecules, and a xanthine-catechin mixture (XC mixture. We evaluated the effects of these treatments on cell proliferation, cell cycle progression, oxidative and antioxidant marker expression, cytokine levels, gene expression, and GSK-3β enzyme expression. Treatment with the XC mixture potentialized Li-induced anti-inflammatory effects by intensification of the following: GSK-3β inhibitory action, lowering effect on proinflammatory cytokines (IL-1β, IL-6, and TNFα, and increase in the levels of IL-10 that is an anti-inflammatory cytokine. Despite the controversial nature of caffeine consumption by BD patients, these results suggested that consumption of caffeine, in low concentrations, mixed with other bioactive molecules along with Li may be safe.

  13. Xanthine-Catechin Mixture Enhances Lithium-Induced Anti-Inflammatory Response in Activated MacrophagesIn Vitro.

    Science.gov (United States)

    Barbisan, Fernanda; Azzolin, Verônica Farina; Teixeira, Cibele Ferreira; Mastella, Moisés Henrique; Ribeiro, Euler Esteves; do Prado-Lima, Pedro Antonio Schmidt; Praia, Raquel de Souza; Medeiros Frescura Duarte, Marta Maria; da Cruz, Ivana Beatrice Mânica

    2017-01-01

    Lithium (Li) is a chemical element used for treating and preventing bipolar disorder (BD) and exerts positive effects such as anti-inflammatory effects as well as undesirable side effects. These effects of Li can be influenced by interaction with some nutritional elements. Therefore, we investigated the potential effects of xanthine (caffeine and theobromine) and catechin molecules present in some food beverages broadly consumed worldwide, such as coffee and tea, on Li-induced anti-inflammatory effects. In the present study, we concomitantly exposed RAW 264.7 macrophages to Li, isolated xanthine and catechin molecules, and a xanthine-catechin mixture (XC mixture). We evaluated the effects of these treatments on cell proliferation, cell cycle progression, oxidative and antioxidant marker expression, cytokine levels, gene expression, and GSK-3 β enzyme expression. Treatment with the XC mixture potentialized Li-induced anti-inflammatory effects by intensification of the following: GSK-3 β inhibitory action, lowering effect on proinflammatory cytokines (IL-1 β , IL-6, and TNF α ), and increase in the levels of IL-10 that is an anti-inflammatory cytokine. Despite the controversial nature of caffeine consumption by BD patients, these results suggested that consumption of caffeine, in low concentrations, mixed with other bioactive molecules along with Li may be safe.

  14. Coffee, tea, soda, and caffeine intake in relation to risk of adult glioma in the NIH-AARP Diet and Health Study.

    Science.gov (United States)

    Dubrow, Robert; Darefsky, Amy S; Freedman, Neal D; Hollenbeck, Albert R; Sinha, Rashmi

    2012-05-01

    We utilized the large, prospective NIH-AARP Diet and Health Study to further explore the hypothesis, suggested by two recent prospective cohort studies, that increased intake of coffee, tea, soda, and/or caffeine is associated with reduced adult glioma risk. At baseline in 1995-1996, dietary intake, including coffee, tea, and soda, was assessed with a food frequency questionnaire. We used Cox proportional hazards models to calculate adjusted hazard ratios (HR) and 95 % confidence intervals (CI) for glioma risk in relation to beverage intake. During follow-up of 545,771 participants through 2006, 904 participants were diagnosed with glioma. We found no trends of decreasing glioma risk with increasing intake of specific beverages or total caffeine. HR patterns for consumption of the caffeinated versus decaffeinated form of each beverage were inconsistent with a specific caffeine effect. HR patterns of reduced glioma risk for most categories of beverage intake greater than "none" prompted a post hoc analysis that revealed borderline-significant inverse associations for any versus no intake of tea (HR = 0.84; 95 % CI, 0.69-1.03), total coffee plus tea (HR = 0.70; 95 % CI, 0.48-1.03), and soda (HR = 0.82; 95 % CI, 0.67-1.01). The borderline-significant inverse associations could be explained by a threshold effect in which any beverage intake above a low level confers a beneficial effect, most likely due to beverage constituents other than caffeine. They could also be explained by non-drinkers of these beverages sharing unknown extraneous characteristics associated with increased glioma risk, or by chance.

  15. Effect of teapot materials on the chemical composition of oolong tea infusions.

    Science.gov (United States)

    Liao, Zih-Hui; Chen, Ying-Jie; Tzen, Jason Tze-Cheng; Kuo, Ping-Chung; Lee, Maw-Rong; Mai, Fu-Der; Rairat, Tirawat; Chou, Chi-Chung

    2018-01-01

    The flavor and quality of tea are widely believed to be associated with the pot in which the tea is made. However, this claim is mostly by experiences and lacks solid support from scientific evidence. The current study investigated and compared the chemical compositions of oolong tea made with six different teapot materials, namely Zisha, Zhuni, stainless steel, ceramic, glass and plastic. For each tea sample, polyphenols and caffeine were examined by HPLC-UV, volatile compounds by GC/MS, amino acids by LC/MS and minerals by ICP-MS. The results suggested that tea infusions from Zisha and Zhuni pots contain higher levels of EGC, EGCG and total catechins and less caffeine than those from ceramic, glass and plastic pots and tend to have the lowest total mineral contents, potassium and volatile compounds in tea soup. The statistical differences were not all significant among Zisha, Zhuni and stainless steel pots. Based on the overall chemical composition of the tea infusion, Yixing clay pots (Zisha and Zhuni) produce tea infusions that are presumably less bitter and more fragrant and tend to contain more healthful compounds than tea infusions from other pots. The results could partially explain why Yixing clay pots are among the most popular teapots. The beneficial effects of long-term repeated use of these teapots warrants further study. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. [Fast Detection of Camellia Sinensis Growth Process and Tea Quality Informations with Spectral Technology: A Review].

    Science.gov (United States)

    Peng, Ji-yu; Song, Xing-lin; Liu, Fei; Bao, Yi-dan; He, Yong

    2016-03-01

    The research achievements and trends of spectral technology in fast detection of Camellia sinensis growth process information and tea quality information were being reviewed. Spectral technology is a kind of fast, nondestructive, efficient detection technology, which mainly contains infrared spectroscopy, fluorescence spectroscopy, Raman spectroscopy and mass spectroscopy. The rapid detection of Camellia sinensis growth process information and tea quality is helpful to realize the informatization and automation of tea production and ensure the tea quality and safety. This paper provides a review on its applications containing the detection of tea (Camellia sinensis) growing status(nitrogen, chlorophyll, diseases and insect pest), the discrimination of tea varieties, the grade discrimination of tea, the detection of tea internal quality (catechins, total polyphenols, caffeine, amino acid, pesticide residual and so on), the quality evaluation of tea beverage and tea by-product, the machinery of tea quality determination and discrimination. This paper briefly introduces the trends of the technology of the determination of tea growth process information, sensor and industrial application. In conclusion, spectral technology showed high potential to detect Camellia sinensis growth process information, to predict tea internal quality and to classify tea varieties and grades. Suitable chemometrics and preprocessing methods is helpful to improve the performance of the model and get rid of redundancy, which provides the possibility to develop the portable machinery. Future work is to develop the portable machinery and on-line detection system is recommended to improve the further application. The application and research achievement of spectral technology concerning about tea were outlined in this paper for the first time, which contained Camellia sinensis growth, tea production, the quality and safety of tea and by-produce and so on, as well as some problems to be solved

  17. Coffee, tea and caffeine intake and the risk of severe depression in middle-aged Finnish men: the Kuopio Ischaemic Heart Disease Risk Factor Study.

    Science.gov (United States)

    Ruusunen, Anu; Lehto, Soili M; Tolmunen, Tommi; Mursu, Jaakko; Kaplan, George A; Voutilainen, Sari

    2010-08-01

    Only a few cross-sectional studies have assessed the association between coffee, tea and caffeine and the risk of depression. Our aim was to determine the association in a population-based cohort study. The population-based Kuopio Ischaemic Heart Disease Risk Factor Study cohort was recruited between 1984 and 1989 and followed until the end of 2006. We investigated the association between the intake of coffee, tea and caffeine and depression. Eastern Finland. Middle-aged men (n 2232). Altogether, forty-nine men received a discharge diagnosis of depression. We classified subjects into quartiles according to their mean daily coffee intake: non-drinkers (n 82), light drinkers (813 ml/d, n 390). Heavy drinkers had a decreased risk (RR = 0.28, 95 % CI 0.08, 0.98) for depression when compared with non-drinkers, after adjustment for age and examination years. Further adjustment for socio-economic status, alcohol consumption, smoking, maximal oxygen uptake, BMI and the energy-adjusted daily intakes of folate and PUFA did not attenuate this association (relative risk (RR) = 0.23, 95 % CI 0.06, 0.83). No associations were observed between depression and intake of tea (drinkers v. non-drinkers; RR = 1.19, 95 % CI 0.54, 2.23) or caffeine (highest quartile v. lowest quartile; RR = 0.99, 95 % CI 0.40, 2.45). Coffee consumption may decrease the risk of depression, whereas no association was found for tea and caffeine intake.

  18. Chocolate as a source of tea flavonoids

    NARCIS (Netherlands)

    Arts, I.C.W.; Hollman, P.C.H.; Kromhout, D.

    1999-01-01

    The antioxidant catechin content of chocolate is four times that of tea. Chocolate contributed 20% of the catechin intake in a representative sample of the Dutch population, and tea contributes 55%. Epidemiological assessments of health effects of tea should include other foods that are sources of

  19. The genetics of tea and coffee drinking and preference for source of caffeine in a large community sample of Australian twins.

    Science.gov (United States)

    Luciano, Michelle; Kirk, Katherine M; Heath, Andrew C; Martin, Nicholas G

    2005-10-01

    To investigate the genetic and environmental influences on tea consumption and their commonalities with coffee consumption; and to further examine the genetic and environmental aetiology of preference for tea/coffee. A classical twin design was used in which the similarity of identical and non-identical twins is compared, enabling estimates of genetic, common environmental and unique environmental influence on the trait. An Australian population-based sample of 1796 identical (i.e. monozygotic) and 2013 non-identical (i.e. dizygotic) twin pairs aged 16-87 years was studied, roughly three-fifths of whom were female. The sample represented approximately 70% of those approached for study participation. As part of a Health and Lifestyle Questionnaire, respondents were asked how many cups of each tea and coffee they consumed per day. Additional measures of 'total tea and coffee consumption' and 'preference for coffee' were calculated. Age was positively associated with tea consumption but negatively associated with coffee preference; women consumed more beverages than men, but showed a lower preference for coffee. An inverse relation between tea and coffee consumption--larger in females (-0.41) than males (-0.34)--was supported. This association was mediated entirely by the unique environment in males, and by both the unique environment (68.3%) and genes (31.7%) in females. Tea and coffee drinking were shown to have similar heritabilities (0.46) in males, but tea consumption was influenced by common environmental factors whereas coffee consumption was not. Coffee preference was shown to be influenced by genes (0.42) and the unique environment (0.58). As the patterns of genetic and environmental variation were shown to differ for tea and coffee consumption it may be more informative to retain them as separate measures of caffeine intake in future studies of stimulant use and taste perception.

  20. The determination of catechins and phenylpropanoid acids in selected

    OpenAIRE

    Křížová, Šárka

    2015-01-01

    Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of: Pharmacognosy Candidate: Mgr. Šárka Křížová Consultant: PharmDr. Jan Martin, Ph.D. Title of Thesis: The determination of catechins and phenylpropanoid acids in selected dietary supplements Key words: dietary supplements, green coffee, green tea, guarana, catechins, phenylpropanoid acids. This work was focused on the determination of catechins and phenylpropanoid acids in selected dietary supplements. We selecte...

  1. 'Benifuuki' Green Tea Containing O-Methylated Catechin Reduces Symptoms of Japanese Cedar Pollinosis: A Randomized, Double- Blind, Placebo-Controlled Trial

    Directory of Open Access Journals (Sweden)

    Sawako Masuda

    2014-01-01

    Conclusions: 'Benifuuki' green tea containing a large amount of O-methylated EGCG reduced the symptoms of JCP and has potential as a complementary/alternative medicine for treating seasonal allergic rhinitis.

  2. Healthy properties of green and white teas: an update.

    Science.gov (United States)

    Pastoriza, S; Mesías, M; Cabrera, C; Rufián-Henares, J A

    2017-08-01

    Green tea has been consumed for centuries in Japan, China and Morocco. White tea, which is considered a variety of green tea, is mostly consumed in China and is very appreciated for its flavor. Currently the consumption of both types of tea has been extended to the western countries even as a functional ingredient. A group of polyphenols called catechins stands out among their bioactive components, the most abundant being the (-) epigallocatechin gallate, with high antioxidant power. Teas also contain other phenolic compounds such as gallic, caffeic, chlorogenic or cinnamic acids, quercetin and proanthocyanidols, caffeine, theophylline, l-theanine and minerals such as fluorine, manganese or chromium. Investigations have mainly been focused on their antioxidant potential and their implication in the prevention and treatment of degenerative diseases. Several studies have evaluated their role in cardiovascular diseases, body weight control, bone mass increase, protection against neurodegenerative diseases and improvement of type 2 diabetes, among other pathologies. The main points of controversy are the design and interpretation of epidemiological and human intervention studies and the lack of information on catechins availability, metabolism and biotransformation. This review compiles and analyzes the latest peer-reviewed papers published from 2002 up to February 2017, including systematic reviews and meta-analyses.

  3. Tea and health: preventive and therapeutic usefulness in the elderly?

    Science.gov (United States)

    Bolling, Bradley W; Chen, Chung-Yen Oliver; Blumberg, Jeffrey B

    2009-01-01

    To update the growing literature suggesting that tea and its constituent flavonoids are inversely related to the risk of chronic diseases common among the elderly. Results are provided from recent observational studies and clinical trials on the relationship of tea and tea catechins to body weight control and energy metabolism, impaired glucose tolerance and diabetes, cardiovascular disease, bone mineral density, cognitive function and neurodegenerative disease, and cancer. The evidence for the efficacy and potency of tea and tea extracts in benefiting these outcomes ranges from compelling for cardiovascular disease to equivocal at best for some forms of cancer. Although randomized clinical trials of tea have generally been of short duration and with small sample sizes, together with experimental and epidemiological studies, the totality of the data suggests a role for tea in health promotion as a beverage absent in calories and rich in phytochemicals. Further research is warranted on the putative benefits of tea and the potential for synergy among its constituent flavonoids, L-theanine, and caffeine.

  4. Acute effects of tea constituents L-theanine, caffeine, and epigallocatechin gallate on cognitive function and mood: a systematic review and meta-analysis.

    Science.gov (United States)

    Camfield, David A; Stough, Con; Farrimond, Jonathon; Scholey, Andrew B

    2014-08-01

    A systematic review and meta-analysis was conducted on 11 randomized placebo-controlled human studies of acute effects of tea constituents L-theanine and epigallocatechin gallate, administered alone or in combination with caffeine, on cognitive function and mood. The outcome measures of mood were alertness, calmness, and contentedness, derived from the Bond-Lader scales, and state anxiety, from the State-Trait Anxiety Inventory. Cognitive measures assessed were attentional switch, intersensory attention, and rapid visual information processing. Standardized mean differences between placebo and treatment groups are presented for each study and outcome measure. Meta-analysis using a random-effects model was conducted when data were available for three or more studies. Evidence of moderate effect sizes in favor of combined caffeine and L-theanine in the first 2 hours postdose were found for outcome measures Bond-Lader alertness, attentional switching accuracy, and, to a lesser extent, some unisensory and multisensory attentional outcomes. Moderator analysis of caffeine and L-theanine doses revealed trends toward greater change in effect size for caffeine dose than for L-theanine dose, particularly during the first hour postdose. © 2014 International Life Sciences Institute.

  5. Changes of Constituents and Activity to Apoptosis and Cell Cycle During Fermentation of Tea

    Science.gov (United States)

    Zhao, Hang; Zhang, Min; Zhao, Lu; Ge, Ya-kun; Sheng, Jun; Shi, Wei

    2011-01-01

    Tea is believed to be beneficial for health, and the effects of the fermentation process on its contributions to apoptosis and cell cycle arrest of gastric cancer cells have not been completely investigated. In this study, the chemical components in green tea, black tea and pu-erh tea aqueous extracts were analyzed and compared. The polysaccharide and caffeine levels were substantially higher in the fermented black tea and pu-erh tea, while the polyphenol level was higher in the unfermented green tea. Hence, a treatment of tea aqueous extract and the components, which are emerging as promising anticancer agents, were pursued to determine whether this treatment could lead to enhance apoptosis and cell cycle arrest. In the human gastric cancer cell line SGC-7901, the cell viability and flow cytometry analysis for apoptotic cells indicated effects in a dose-dependent inhibition manner for the three tea treatment groups. The apoptosis rates were found to be elevated after 48 h of treatment with 31.2, 125, and 500 μg/mL of green tea extract, the higher catechins content may be involved in the mechanism. Cell cycle was arrested in S phase in the fermented black tea and pu-erh tea, and the populations were significantly decreased in G2/M phases, possibly due to the oxidation of tea polyphenols, which causes an increase of theabrownins. CCC-HEL-1 normal cells were not sensitive to tea extract. These findings suggest that the fermentation process causes changes of the compounds which might be involved in the changes of cell proliferation inhibition, apoptosis induction and cell cycle arrest. PMID:21673927

  6. Altering the phenolics profile of a green tea leaves extract using exogenous oxidases

    NARCIS (Netherlands)

    Verloop, A.J.W.; Gruppen, H.; Bisschop, Robbin; Vincken, Jean Paul

    2016-01-01

    Transformation from green tea leaves into black tea involves oxidation of catechins into theaflavins and other complex phenolics by endogenous enzymes in tea leaves. By employing tyrosinase and laccase, both from Agaricus bisporus, on green tea catechins, the oxidation process was directed

  7. Polyphenol content of plasma and litter after the oral administration of green tea and tea polyphenols in chickens.

    Science.gov (United States)

    Zhou, Yi-Bin; Wan, Xiao-Chun; Shang, Yan-Yan; Hu, Jing-Wei; Shao, Lei; Chen, Wei; Li, Da-Xiang

    2012-02-22

    Metabolic profiles of broiler chickens were examined after the ingestion of green tea, tea polyphenols, and (-)-epigallocatechin-3-gallate (EGCG). Solid-phase extraction of serum and litters yielded free catechins and their metabolites, which were then identified and quantified by liquid chromatography-tandem mass spectrometry. In plasma samples, (-)-gallocatechin, (+)-catechin, and EGCG were detected in the green tea group; pyrogallol acid, (epi)catechin-O-sulfate, 4'-O-methyl-(epi)gallocatechin-O-glucuronide, and (epi)catechin-3'-O-glucuronide were detected in the tea polyphenols group; and EGCG, (-)-gallocatechin gallate (GCG), and 4'-O-methyl-(epi)gallocatechin-O-glucuronides were detected in the EGCG group. In litters, gallic acid, EGCG, GCG, and ECG were detected in the green tea and tea polyphenols groups; EGCG and ECG were detected in the EGCG group. The conjugated metabolites, 4'-O-methyl-(epi)gallocatechin-O-glucuronide, (epi)catechin-3'-glucuronide, and 4'-O-methyl-(epi)catechin-O-sulfate, were identified in the green tea group; 4'-O-methyl-(epi)catechin-O-sulfate and 4'-O-methyl-(epi)gallocatechin-O-sulfate were identified in the tea polyphenols group; only 4'-O-methyl-(epi)gallocatechin-O-sulfate was detected in the EGCG group. The excretion of tea catechins was 95.8, 87.7, and 97.7% for the green tea, tea polyphenols, and EGCG groups, respectively.

  8. The acute effects of green tea and carbohydrate coingestion on systemic inflammation and oxidative stress during sprint cycling.

    Science.gov (United States)

    Suzuki, Katsuhiko; Takahashi, Masaki; Li, Chia-Yang; Lin, Shiuan-Pey; Tomari, Miki; Shing, Cecilia M; Fang, Shih-Hua

    2015-10-01

    Green tea (Camellia sinensis) has anti-oxidative and anti-inflammatory effects, which may be beneficial to athletes performing high-intensity exercise. This study investigated the effects of carbohydrate and green tea coingestion on sprint cycling performance and associated oxidative stress and immunoendocrine responses to exercise. In a crossover design, 9 well-trained male cyclists completed 3 sets of 8 repetitions of 100-m uphill sprint cycling while ingesting green tea and carbohydrate (TEA) (22 mg/kg body mass catechins, 6 mg/kg body mass caffeine, 230 mg/kg glucose, and 110 mg/kg fructose) or carbohydrate only (CHO) (230 mg/kg body mass glucose and 110 mg/kg body mass fructose) during each 10-min recovery period between sets. Blood samples were collected before exercise, 10 min after exercise, and 14 h after exercise. There was no effect of acute TEA ingestion on cycling sprint performance (p = 0.29), although TEA maintained postexercise testosterone and lymphocyte concentrations, which decreased significantly in the CHO group (p TEA (p = 0.05), there were no significant differences between TEA and CHO for circulating cytokines (p > 0.20), markers of oxidative stress and antioxidant capacity (p > 0.17), adiponectin concentration (p = 0.60), or muscle damage markers (p > 0.64). While acute green tea ingestion prevents the postexercise decrease in testosterone and lymphocytes, it does not appear to benefit cycling sprint performance or reduce markers of oxidation and inflammation when compared with carbohydrate alone.

  9. A study on quality components and sleep-promoting effects of GABA black tea.

    Science.gov (United States)

    Zhao, Wenfang; Li, Yun; Ma, William; Ge, Yazhong; Huang, Yahui

    2015-10-01

    The aims of this study were to analyze the changes in quality components of gamma (γ)-aminobutyric acid (GABA) black tea during processing, and to investigate the effect of three dosages of GABA black tea on sleep improvement. The results showed that the GABA content was increased significantly up to 2.70 mg g(-1) after vacuum anaerobic and aerobic treatment. In addition, the content of GABA after drying reached 2.34 mg g(-1), which achieved the standard of GABA tea. During the entire processing of GABA black tea, the contents of tea polyphenols, caffeine and total catechins displayed a gradually descending trend, while the contents of free amino acids and GABA were firstly increased, and then reduced. The GABA black tea had significant effects on prolonging the sleeping time with sodium pentobarbital (P sleeping rate induced by sodium pentobarbital at a sub-threshold dose (P sleeping latency period induced by sodium barbital was not significant (P > 0.05). It had no effect on directly inducing sleep and the mouse body weight. The extract of GABA black tea improved the sleeping quality of mice to extend with an optimal effect being found in the high dose-treated mice.

  10. Variations of Antioxidant Properties and NO Scavenging Abilities during Fermentation of Tea

    Science.gov (United States)

    Xu, Yang; Zhao, Hang; Zhang, Min; Li, Chun-Jie; Lin, Xue-Zhen; Sheng, Jun; Shi, Wei

    2011-01-01

    Tea is known as one of the most popular beverages in the world, which is believed to be beneficial for health. The main components in tea will change a lot depending on the different processes of fermentation, and thus the effects of different teas on human health may differ. The aim of this study is to explore the varied abilities of reactive oxygen species (ROS) and nitric oxide (NO) scavenging during the fermentation of tea. In this study, we conducted the in vitro experiments which involved some reaction systems indicating the abilities of scavenging ROS and NO. We also investigated the effects of tea and their components (catechins, theabrownins, caffeine) on the intracellular levels of ROS and NO, using Raw 264.7 cells as the model. We found that regardless of whether it was out of cell system or in Raw 264.7 cells, the abilities of scavenging ROS would decrease during the fermentation of tea. Further, the post-fermented pu-erh tea showed the best effect on inhibiting the lipopolysaccharide (LPS)-induced production of NO. These findings indicated that the fermentation process caused a change of the components which might be due to the changes of their antioxidant properties and NO scavenging abilities. PMID:21845097

  11. New Sample Preparation Method for Quantification of Phenolic Compounds of Tea (Camellia sinensis L. Kuntze: A Polyphenol Rich Plant

    Directory of Open Access Journals (Sweden)

    P. A. Nimal Punyasiri

    2015-01-01

    Full Text Available Chemical analysis of the Sri Lankan tea (Camellia sinensis, L. germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols, are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures and freeze-dried leaves (a new procedure, for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolites such as catechins, caffeine, gallic acid, and theobromine, recorded in the new sampling procedure via freeze-dried leaves, were significantly higher than those recorded in the conventional sample preparation procedure. Additionally new method required less amount of leaf sample for analysis of major metabolites and facilitates storage of samples until analysis. The freeze-dried method would be useful for high throughput analysis of large number of samples in shorter period without chemical deterioration starting from the point of harvest until usage. Hence, this method is more suitable for metabolite profiling of tea as well as other phenol rich plants.

  12. Discrimination of the production season of Chinese green tea by chemical analysis in combination with supervised pattern recognition.

    Science.gov (United States)

    Xu, Wenping; Song, Qiushuang; Li, Daxiang; Wan, Xiaochun

    2012-07-18

    High-performance liquid chromatography (HPLC) has been used to quantify levels of free amino acids, catechins, and caffeine in Chinese green tea. Levels of free amino acids and catechins in green tea leaves show obvious variation from spring to summer, which is useful information to identify the production season of commercial green tea. Supervised pattern recognition methods such as the K-nearest neighbor (KNN) method and Bayesian discriminant method (a type of linear discriminant analysis (LDA)) were used to discriminate between the production seasons of Chinese green tea. The optimal accuracy of the KNN method was ≤97.61 and ≤94.80% as validated by resubstitution and cross-validation tests, respectively, and that of LDA was ≤95.22 and ≤93.54%, respectively. Compared with LDA, the KNN method did not require a Gaussian distribution and was more accurate than LDA. The KNN method in combination with chemical analysis is recommended for discrimination of the production seasons of Chinese green tea.

  13. Adsorption characteristics of (-)-epigallocatechin gallate and caffeine in the extract of waste tea on macroporous adsorption resins functionalized with chloromethyl, amino, and phenylamino groups.

    Science.gov (United States)

    Liu, Yongfeng; Bai, Qingqing; Lou, Song; Di, Duolong; Li, Jintian; Guo, Mei

    2012-02-15

    According to the Friedel-Crafts and amination reaction, a series of macroporous adsorption resins (MARs) with novel structures were synthesized and identified by the Brunauer-Emmett-Teller (BET) method and Fourier transform infrared (FTIR) spectra, and corresponding adsorption behaviors for (-)-epigallocatechin gallate (EGCG) and caffeine (CAF) extracted from waste tea were systemically investigated. Based on evaluation of adsorption kinetics, the kinetic data were well fitted by pseudo-second-order kinetics. Langmuir, Freundlich, Temkin-Pyzhev, and Dubinin-Radushkevich isotherms were selected to illustrate the adsorption process of EGCG and CAF on the MARs. Thermodynamic parameters were adopted to explain in-depth information of inherent energetic changes associated with the adsorption process. The effect of temperature on EGCG and CAF adsorption by D101-3 was further expounded. Van der Waals force, hydrogen bonding, and electrostatic interaction were the main driving forces for the adsorption of EGCG and CAF on the MARs. This study might provide a scientific reference point to aid the industrial large-scale separation and enrichment of EGCG from the extracts of waste tea using modified MARs.

  14. Chemical synthesis of tea polyphenols and related compounds.

    Science.gov (United States)

    Asakawa, Tomohiro; Hamashima, Yoshitaka; Kan, Toshiyuki

    2013-01-01

    Tea polyphenol "catechin", which is a major constituent of green tea extract, has received special attention for its important bioactivities. In this article, we review the recent various syntheses of catechins by classifying the mode of of flavan ring-construction. Additionally, we also take notice of the application of the modified catechins that were created to uncover the mechanism of bioactivities and discover new activities.

  15. Bactericidal catechins damage the lipid bilayer.

    Science.gov (United States)

    Ikigai, H; Nakae, T; Hara, Y; Shimamura, T

    1993-04-08

    The mode of antibacterial action of, the green tea (Camellia sinensis) extracts, (-)-epigallocatechin gallate (EGCg) and (-)-epicatechin (EC) was investigated. Strong bactericidal EGCg caused leakage of 5,6-carboxyfluorescein from phosphatidylcholine liposomes (PC), but EC with very weak bactericidal activity caused little damage to the membrane. Phosphatidylserine and dicetyl phosphate partially protected the membrane from EGCg-mediated damage when reconstituted into the liposome membrane with PC. EGCg, but not EC, caused strong aggregation and NPN-fluorescence quenching of PC-liposomes and these actions were markedly lowered in the presence of negatively charged lipids. These results show that bactericidal catechins primarily act on and damage bacterial membranes. The observation that Gram-negative bacteria are more resistant to bactericidal catechins than Gram-positive bacteria can be explained to some extent by the presence of negatively charged lipopolysaccharide.

  16. Long-Term Green Tea Supplementation Does Not Change the Human Gut Microbiota.

    Science.gov (United States)

    Janssens, Pilou L H R; Penders, John; Hursel, Rick; Budding, Andries E; Savelkoul, Paul H M; Westerterp-Plantenga, Margriet S

    2016-01-01

    Green tea catechins may play a role in body weight regulation through interactions with the gut microbiota. We examined whether green tea supplementation for 12 weeks induces changes in composition of the human gut microbiota. 58 Caucasian men and women were included in a randomized, placebo-controlled design. For 12 weeks, subjects consumed either green tea (>0.56 g/d epigallocatechin-gallate + 0.28 ∼ 0.45 g/d caffeine) or placebo capsules. Fecal samples were collected twice (baseline, vs. week 12) for analyses of total bacterial profiles by means of IS-profiling, a 16S-23S interspacer region-based profiling method. No significant changes between baseline and week 12 in subjects receiving green tea or placebo capsules, and no significant interactions between treatment (green tea or placebo) and time (baseline and week 12) were observed for body composition. Analysis of the fecal samples in subjects receiving green tea and placebo showed similar bacterial diversity and community structures, indicating there were no significant changes in bacterial diversity between baseline and week 12 in subjects receiving green tea capsules or in subjects receiving placebo capsules. No significant interactions were observed between treatment (green tea or placebo) and time (baseline and week 12) for the gut microbial diversity. Although, there were no significant differences between normal weight and overweight subjects in response to green tea, we did observe a reduced bacterial alpha diversity in overweight as compared to normal weight subjects (p = 0.002). Green tea supplementation for 12 weeks did not have a significant effect on composition of the gut microbiota. ClinicalTrials.gov NCT01556321.

  17. Study on tea leaves extract as green corrosion inhibitor of mild steel in hydrochloric acid solution

    Science.gov (United States)

    Hamdan, A. B.; Suryanto; Haider, F. I.

    2018-01-01

    Corrosion inhibitor from extraction of plant has been considered as the most preferable and most chosen technique to prevent corrosion of metal in acidic medium because of the environmental friendly factor. In this study, black tea leaves extraction was tested as corrosion inhibitor for mild steel in 0.1M of hydrochloric acid (HCl) with the absence and presence of corrosion inhibitor. The efficiency and effectiveness of black tea as corrosion inhibitor was tested by using corrosion weight loss measurement experiment was carried out with varies parameters which with different concentration of black tea extract solution. The extraction of black tea solution was done by using aqueous solvent method. The FT-IR result shows that black tea extract containing compounds such as catechin, caffeine and tannins that act as anti-corrosive reagents and responsible to enhance the effectiveness of black tea extract as corrosion inhibitor by forming the hydrophobic thin film through absorption process. As a result of weight loss measurement, it shows that loss in weight of mild steel reduces as the concentration of inhibitor increases. The surface analysis was done on the mild steel samples by using SEM.

  18. Tea (Camellia sinensis (L.)): a putative anticancer agent in bladder carcinoma?

    Science.gov (United States)

    Conde, Vanessa R; Alves, Marco G; Oliveira, Pedro F; Silva, Branca M

    2015-01-01

    The leaves of Camellia sinensis (L.) are the source of tea, the second most consumed beverage worldwide. Tea contains several chemical compounds such as polyphenols (mainly catechins), caffeine, theophylline, L-theanine, among many others. Polyphenolic compounds are mainly responsible for its significant antioxidant properties and anticarcinogenic potential. Bladder cancer is one of the most common types of cancer, and its progression and onset are thought to be controlled by dietary and lifestyle factors. Epidemiological studies showed that the regular consumption of tea can be a preventive factor for this type of cancer, and several in vivo and in vitro studies reported that tea and its components may interfere in the cancer cells' signaling, preventing the bladder tumor progression. The mechanisms responsible for this protection include deregulation of cell cycle, induction of apoptosis while protecting the surrounding healthy bladder cells, inhibition of metastization processes, among others. Herein, we discuss the potential beneficial effects of tea and tea components in bladder cancer prevention and/or treatment, and how they can be helpful in finding new therapeutic strategies to treat this type of cancer.

  19. Effect of Brewing Duration on the Antioxidant and Hepatoprotective Abilities of Tea Phenolic and Alkaloid Compounds in a t-BHP Oxidative Stress-Induced Rat Hepatocyte Model

    Directory of Open Access Journals (Sweden)

    Laura Braud

    2015-08-01

    Full Text Available Tea is an interesting source of antioxidants capable of counteracting the oxidative stress implicated in liver diseases. We investigated the impact of antioxidant molecules provided by a mixture of teas’ leaves (green, oolong, pu-erh after different infusion durations in the prevention of oxidative stress in isolated rat hepatocytes, by comparison with pure epigallocatechin-3-gallate (EGCG, the main representative of tea catechins. Dried aqueous tea extracts (ATE obtained after 5, 15 and 30 min infusion time were characterized for total polyphenols (gallic acid equivalent, catechins, gallic acid and caffeine (HPLC-DAD/ESI-MS contents, and for scavenging ability against 2,2-diphenyl-1-picrylhydrazyl free radical. Hepatoprotection was evaluated through hepatocyte viability tests using tert-butyl hydroperoxide as a stress inducer, (3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, neutral red uptake, real-time cellular impedance and mitochondrial function tests. We showed that a 5-min incubation time is sufficient for an optimal bioaccessibility of tea compounds with the highest antioxidative ability, which decreases for longer durations. A 4-h pretreatment of cells with ATE significantly prevented cell death by regulating reactive oxygen species production and maintaining mitochondrial integrity. Pure EGCG, at doses similar in ATE (5–12 µM, was inefficient, suggesting a plausible synergy of several water-soluble tea compounds to explain the ATE beneficial effects.

  20. Catechins and Their Therapeutic Benefits to Inflammatory Bowel Disease

    Directory of Open Access Journals (Sweden)

    Fei-Yan Fan

    2017-03-01

    Full Text Available Catechins are natural polyphenolic phytochemicals that exist in food and medicinal plants, such as tea, legume and rubiaceae. An increasing number of studies have associated the intake of catechins-rich foods with the prevention and treatment of chronic diseases in humans, such as inflammatory bowel disease (IBD. Some studies have demonstrated that catechins could significantly inhibit the excessive oxidative stress through direct or indirect antioxidant effects and promote the activation of the antioxidative substances such as glutathione peroxidases (GPO and glutathione (GSH, reducing the oxidative damages to the colon. In addition, catechins can also regulate the infiltration and proliferation of immune related-cells, such as neutrophils, colonic epithelial cells, macrophages, and T lymphocytes, helping reduce the inflammatory relations and provide benefits to IBD. Perhaps catechins can further inhibit the deterioration of intestinal lesions through regulating the cell gap junctions. Furthermore, catechins can exert their significant anti-inflammatory properties by regulating the activation or deactivation of inflammation-related oxidative stress-related cell signaling pathways, such as nuclear factor-kappa B (NF-κB, mitogen activated protein kinases (MAPKs, transcription factor nuclear factor (erythroid-derived 2-like 2 (Nrf2, signal transducer and the activator of transcription 1/3 (STAT1/3 pathways. Finally, catechins can also stabilize the structure of the gastrointestinal micro-ecological environment via promoting the proliferation of beneficial intestinal bacteria and regulating the balance of intestinal flora, so as to relieve the IBD. Furthermore, catechins may regulate the tight junctions (TJ in the epithelium. This paper elaborates the currently known possible molecular mechanisms of catechins in favor of IBD.

  1. Polyphenol- and Caffeine-Rich Postfermented Pu-erh Tea Improves Diet-Induced Metabolic Syndrome by Remodeling Intestinal Homeostasis in Mice.

    Science.gov (United States)

    Gao, Xiaoyu; Xie, Qiuhong; Kong, Ping; Liu, Ling; Sun, Sheng; Xiong, Boyu; Huang, Baojia; Yan, Liang; Sheng, Jun; Xiang, Hongyu

    2018-01-01

    Postfermented Pu-erh tea (PE) protects against metabolic syndrome (MS), but little is known regarding its underlying mechanisms. Animal experiments were performed to determine whether the gut microbiota mediated the improvement in diet-induced MS by PE and its main active components (PEAC). We confirmed that PE altered the body composition and energy efficiency, attenuated metabolic endotoxemia and systemic and multiple-tissue inflammation, and improved the glucose and lipid metabolism disorder in high-fat diet (HFD)-fed mice via multiple pathways. Notably, PE promoted the lipid oxidation and browning of white adipose tissue (WAT) in HFD-fed mice. Polyphenols and caffeine (CAF) played critical roles in improving these parameters. Meanwhile, PE remodeled the disrupted intestinal homeostasis that was induced by the HFD. Many metabolic changes observed in the mice were significantly correlated with alterations in specific gut bacteria. Akkermansia muciniphila and Faecalibacterium prausnitzii were speculated to be the key gut bacterial links between the PEAC treatment and MS at the genus and species levels. Interestingly, A. muciniphila administration altered body composition and energy efficiency, promoted the browning of WAT, and improved the lipid and glucose metabolism disorder in the HFD-fed mice, whereas F. prausnitzii administration reduced the HFD-induced liver and intestinal inflammatory responses. In summary, polyphenol- and CAF-rich PE improved diet-induced MS, and this effect was associated with a remodeling of the gut microbiota. Copyright © 2017 American Society for Microbiology.

  2. Production, Composition, and Health Effects of Oolong Tea

    OpenAIRE

    İlkay Koca; Şeyda Bostancı

    2014-01-01

    Tea, one of the most widely consumed beverages in the world, is produced from the leaves of the plant Camellia sinensis L.. Tea has important physiological properties and potential health benefits due to the presence of compounds such as polyphenols, amino acids, vitamins, carbohydrates, caffeine, and purine alkaloids. Tea is produced in three types as green tea (unfermented), oolong tea (partially fermented), and black tea (fully fermented). Black tea is consumed worldwide, whereas green and...

  3. Caffeine, sleep and quality of life

    NARCIS (Netherlands)

    Lorist, M.M.; Snel, J.; Verster, J.C.; Pandi-Perumal, S.R.; Streiner, D.L.

    2008-01-01

    Caffeine is regarded as a mild stimulant acting on the central nervous system that is responsible for a significant portion of the behavioural and physiological effects of coffee and tea. Motives why people take caffeine are reflected in consumption patterns. Early in the morning caffeine might help

  4. Caffeine Confusion

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Caffeine Confusion KidsHealth / For Kids / Caffeine Confusion What's in ... cup of coffee. So what is caffeine, anyway? Caffeine Is a Common Chemical Caffeine (say: KA-feen) ...

  5. Spectrophotometric Analysis of Caffeine

    Directory of Open Access Journals (Sweden)

    Showkat Ahmad Bhawani

    2015-01-01

    Full Text Available The nature of caffeine reveals that it is a bitter white crystalline alkaloid. It is a common ingredient in a variety of drinks (soft and energy drinks and is also used in combination with various medicines. In order to maintain the optimum level of caffeine, various spectrophotometric methods have been developed. The monitoring of caffeine is very important aspect because of its consumption in higher doses that can lead to various physiological disorders. This paper incorporates various spectrophotometric methods used in the analysis of caffeine in various environmental samples such as pharmaceuticals, soft and energy drinks, tea, and coffee. A range of spectrophotometric methodologies including chemometric techniques and derivatization of spectra have been used to analyse the caffeine.

  6. Caffeine intake and fecundability

    DEFF Research Database (Denmark)

    Jensen, Tina Kold; Henriksen, T B; Hjollund, N H

    1998-01-01

    Fecundability has been defined as the ability to achieve a recognized pregnancy. Several studies on caffeine and fecundability have been conducted but have been inconclusive. This may be explained partly by lack of stratification by smoking. Furthermore, few researchers have tried to separate...... the effect of caffeine from different sources (coffee, tea, cola, and chocolate). Clearly, the relationship between caffeine and fecundability needs further research, given the high prevalence of caffeine intake among women of childbearing age. We examined the independent and combined effects of smoking...... and caffeine intake from different sources on the probability of conception. From 1992 to 1995, a total of 430 couples were recruited after a nationwide mailing of a personal letter to 52,255 trade union members who were 20 to 35 years old, lived with a partner, and had no previous reproductive experience...

  7. Determination of Caffeine Content in Non-Alcoholic Beverages and ...

    African Journals Online (AJOL)

    alcoholic energy drinks and prepared teas using reverse phase HPLC. Caffeine was extracted from 19 different types of non-alcoholic beverages and prepared teas sampled from supermarkets in Nairobi Central Business District, Kenya. These were ...

  8. Aspectos funcionais das catequinas do chá verde no metabolismo celular e sua relação com a redução da gordura corporal Functional aspects of green tea catechins in the cellular metabolism and their relationship with body fat reduction

    Directory of Open Access Journals (Sweden)

    Renata da Costa Lamarão

    2009-04-01

    Full Text Available O chá é uma bebida amplamente utilizada, perdendo apenas para a água como a bebida mais consumida no mundo. O chá verde é rico em polifenóis, principalmente catequinas. Entre uma variedade de efeitos benéficos à saúde atribuídos ao consumo do chá verde, grande atenção tem sido focalizada no seu efeito na redução da gordura corporal. Este estudo tem como objetivo apresentar uma descrição dos estudos com o chá verde e/ou seus compostos bioativos relacionados à biologia celular, estudos experimentais e epidemiológicos associados ao metabolismo lipídico e à redução da gordura corporal. Galato de epigalocatequina é o principal composto bioativo presente no chá verde e seus efeitos anti-obesidade estão sendo investigados. Tais efeitos estão associados a diversos mecanismos bioquímicos e fisiológicos, dentre eles podem-se destacar a estimulação do metabolismo lipídico pela combinação da ingestão de catequinas e a prática de exercícios físicos regulares. Apesar do efeito promissor do chá verde e seus compostos bioativos no tratamento da obesidade, estudos clínicos controlados devem ser conduzidos. Finalmente, um plano alimentar adequado associado à prática regular de atividade física constitui a principal ferramenta para a prevenção da obesidade e de suas comorbidades.The use of tea is widespread, second only to water in worldwide consumption. Green tea is rich in polyphenols, mainly catechins. Among a variety of beneficial health effects attributed to the consumption of the green tea, much attention has been given to its ability to reduce body fat. This study has the objective of presenting a description of the studies of green tea and/or its bioactive compounds related to cell biology and of experimental and epidemiological studies associated with lipid metabolism and the reduction of body fat. Epigallocatechin gallate is the main bioactive compound present in green tea and its anti-obesity effects are

  9. (--)-Catechin glycosides from Ulmus davidiana.

    Science.gov (United States)

    Hosny, Mohammed; Zheng, Ming-Shan; Zhang, Haiyan; Chang, Hyun-Wook; Woo, Mi-Hee; Son, Jong-Keun; Lee, Sunny Kyung-Seon

    2014-06-01

    Extensive chromatographic separation of the n-BuOH soluble fraction obtained from the stem and root barks of U. davidiana resulted in five hitherto unknown compounds together with a known one (-)-catechin 1. Structures of the five compounds were elucidated by chemical and spectroscopic analyses, to be (-)-catechin-7-O-gallate-5-O-(5″″-trans-caffeoyl)-β-D-apiofuranoside-3-O-β-D-apiofuranosyl-(1 → 2)-β-D-glucopyranoside 2, (-)-catechin-7-O-gallate-5-O-(5″″-trans-caffeoyl)-β-D-apiofuranoside-3-O-β-D-glucopyranoside 3, (-)-catechin-7-O-gallate-5-O-β-D-apiofuranoside-3-O-(2″-O-galloyl)-β-D-glucopyranoside 4, (-)-catechin-7-O-gallate-5-O-(5″″-trans-caffeoyl)-β-D-apiofuranoside 5, and (-)-catechin-7-O-gallate-5-O-(5″″-trans-feruloyl)-β-D-apiofuranoside 6.

  10. Comparative Transcriptome Analysis of Chinary, Assamica and Cambod tea (Camellia sinensis) Types during Development and Seasonal Variation using RNA-seq Technology

    Science.gov (United States)

    Kumar, Ajay; Chawla, Vandna; Sharma, Eshita; Mahajan, Pallavi; Shankar, Ravi; Yadav, Sudesh Kumar

    2016-11-01

    Tea quality and yield is influenced by various factors including developmental tissue, seasonal variation and cultivar type. Here, the molecular basis of these factors was investigated in three tea cultivars namely, Him Sphurti (H), TV23 (T), and UPASI-9 (U) using RNA-seq. Seasonal variation in these cultivars was studied during active (A), mid-dormant (MD), dormant (D) and mid-active (MA) stages in two developmental tissues viz. young and old leaf. Development appears to affect gene expression more than the seasonal variation and cultivar types. Further, detailed transcript and metabolite profiling has identified genes such as F3‧H, F3‧5‧H, FLS, DFR, LAR, ANR and ANS of catechin biosynthesis, while MXMT, SAMS, TCS and XDH of caffeine biosynthesis/catabolism as key regulators during development and seasonal variation among three different tea cultivars. In addition, expression analysis of genes related to phytohormones such as ABA, GA, ethylene and auxin has suggested their role in developmental tissues during seasonal variation in tea cultivars. Moreover, differential expression of genes involved in histone and DNA modification further suggests role of epigenetic mechanism in coordinating global gene expression during developmental and seasonal variation in tea. Our findings provide insights into global transcriptional reprogramming associated with development and seasonal variation in tea.

  11. Consumption of caffeinated beverages and the awareness of their caffeine content among Dutch students.

    Science.gov (United States)

    Mackus, Marlou; van de Loo, Aurora J A E; Benson, Sarah; Scholey, Andrew; Verster, Joris C

    2016-08-01

    The purpose of the current study was to examine the knowledge of caffeine content of a variety of caffeinated beverages among Dutch university students. A pencil-and-paper survey was conducted among N = 800 Dutch students. Most participants (87.8%) reported consuming caffeinated beverages during the past 24 h. Their mean ± SD past 24-h caffeine intake from beverages was 144.2 ± 169.5 mg (2.2 ± 3.0 mg/kg bw). Most prevalent sources of caffeine were coffee beverages (50.8%) and tea (34.8%), followed by energy drink (9.2%), cola (4.7%), and chocolate milk (0.5%). Participants had poor knowledge on the relative caffeine content of caffeinated beverages. That is, they overestimated the caffeine content of energy drinks and cola, and underestimated the caffeine content of coffee beverages. If caffeine consumption is a concern, it is important to inform consumers about the caffeine content of all caffeine containing beverages, including coffee and tea. The current findings support previous research that the most effective way to reduce caffeine intake is to limit the consumption of coffee beverages and tea. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Biological Effects of Green Tea Capsule Supplementation in Pre-Surgery Postmenopausal Breast Cancer Patients

    OpenAIRE

    Yu, Steven S.; Spicer, Darcy V.; Hawes, Debra; Tseng, Chiu-Chen; Yang, Chung S.; Pike, Malcolm C.; Wu, Anna H.

    2013-01-01

    Regular green tea intake has been associated with an inverse risk of breast cancer. There are compelling experimental evidence that green tea, particularly, epigallocatechin gallate, the most potent green tea catechin, possesses a range of anti-cancer properties. We conducted a pre-surgical study of green tea capsules vs. no-green tea in women with primary breast cancer to determine the effects of green tea supplementation on markers of biological response. Postmenopausal women with ductal ca...

  13. Biological Effects of Green Tea Capsule Supplementation in Pre-surgery Postmenopausal Breast Cancer Patients

    OpenAIRE

    Steven S Yu; Darcy V Spicer; Darcy V Spicer; Debra eHawes; Chiu-Chen eTseng; Chung S Yang; Malcolm C Pike; Anna H Wu

    2013-01-01

    Regular green tea intake has been associated with an inverse risk of breast cancer. There is compelling experimental evidence that green tea, particularly, epigallocatechin gallate, the most potent green tea catechin, possesses a range of anti-cancer properties. We conducted a pre-surgical study of green tea capsules versus no green tea in women with primary breast cancer to determine the effects of green tea supplementation on markers of biological response. Postmenopausal women with duct...

  14. The cytogenetic effects of black tea and green tea on cultured human lymphocytes

    Directory of Open Access Journals (Sweden)

    Halil Erhan Eroğlu

    2011-12-01

    Full Text Available In this study, the cytogenetic effects of black tea and green tea were determined in cultured peripheral blood lymphocytes. Results showed that black tea and green tea induced the mitotic and replication indexes and decreased micronuclei. But these data were not statistically significant for green tea. The effects of black tea on the micronucleus formation and mitotic index were statistically significant. The decrease in micronucleus counts indicated that black tea and green tea had considerable anticlastogenic and antigenotoxic effects as observed in vitro in human lymphocytes. Thus, it could be concluded that tea polyphenols protected the normal cells from genotoxic or carcinogenic agents, which indicated the therapeutic and antioxidative role of catechins, flavonoids or other tea compounds.

  15. L-theanine, unique amino acid of tea, and its metabolism, health effects, and safety.

    Science.gov (United States)

    Türközü, Duygu; Şanlier, Nevin

    2017-05-24

    Tea has been a very popular beverage around the world for centuries. The reason that it is delicious, enabling hydration, showing warming and relaxing effect can be mentioned why it is consumed so much in addition to its prominent health effects. Although the catechins and caffeine are the primary bioactive components that are related with the health effects of the tea, the health effects of theanine amino acid, which is a nonproteinic amino acid special to tea, has become prominent in recent years. It has been known that the theanine amino acid in tea has positive effects especially on relaxing, cognitive performance, emotional status, sleep quality, cancer, cardiovascular diseases, obesity, and common cold. The results of acute and chronic toxicity tests conducted on the safety of theanine express that L-theanine is reliable in general even if it is consumed too much with diet. However, it has not revealed a clear evidence-based result yet regarding theanine metabolism, health effects, and its safety. Within this frame, chemical structure of theanine, its biosynthesis, dietary sources, metabolism, health effects, and safety are discussed in present study.

  16. Brassinosteroids Improve Quality of Summer Tea by Balancing Biosynthesis of Polyphenols and Amino Acids in Camellia sinensis L.

    Directory of Open Access Journals (Sweden)

    Xin Li

    2016-08-01

    Full Text Available Summer grown green tea is less popular due to bitterness and high astringency that are attributed to high levels of tea polyphenol (TP and low levels of amino acids (AA in tea leaves (Camellia sinensis L.. Brassinosteroids (BRs, a group of steroidal plant hormones can regulate primary and secondary metabolism in a range of plant species under both normal and stress conditions. However, specific effects of BRs on the photosynthesis of tea plants and the quality of summer green tea are largely unknown. Here we show that 24-epibrassinolide (EBR, a bioactive BR, promoted photosynthesis in tea plants in a concentration-dependent manner. Stimulation in photosynthesis by EBR resulted in an increased summer tea yield. Although all tested concentrations (0.01, 0.05, 0.1, 0.5 and 1.0 ppm increased concentrations of TP and AA, a moderate concentration of EBR (0.5 ppm caused the highest decrease in TP to AA ratio, an important feature of quality tea. Time-course analysis using 0.5 ppm EBR as foliar spray revealed that TP or AA concentration increased as early as 3 h after EBR application, reaching the highest peak at 24 h and that remained more or less stable. Importantly, such changes in TP and AA concentration by EBR resulted in a remarkably decreased but stable TP to AA ratio at 24 h and onward. Furthermore, concentrations of catechins and theanine increased, while that of caffeine remained unaltered following treatment with EBR. EBR improved activity of phenylalanine ammonia-lyase (PAL and glutamine: 2-oxoglutarate (GOGAT enzymes involved in catechins and theanine biosynthesis, respectively. Transcript analysis revealed that transcript levels of CsPAL and CsGS peaked as early as 6 h, while that of CsGOGAT peaked at 12 h following application of EBR, implying that EBR increased the concentration of TP and AA by inducing their biosynthesis. These results suggest a positive role of BR in enhancing green tea quality, which might have potential implication

  17. Energy Drinks and the Neurophysiological Impact of Caffeine

    OpenAIRE

    Persad, Leeana Aarthi Bagwath

    2011-01-01

    Caffeine is the most widely used psychoactive stimulant with prevalent use across all age groups. It is a naturally occurring substance found in the coffee bean, tea leaf, the kola nut, cocoa bean. Recently there has been an increase in energy drink consumption leading to caffeine abuse, with aggressive marketing and poor awareness on the consequences of high caffeine use. With caffeine consumption being so common, it is vital to know the impact caffeine has on the body, as its effects can in...

  18. The Safety of Ingested Caffeine: A Comprehensive Review

    OpenAIRE

    Jennifer L. Temple; Jennifer L. Temple; Christophe Bernard; Steven E. Lipshultz; Jason D. Czachor; Joslyn A. Westphal; Miriam A. Mestre

    2017-01-01

    Caffeine is the most widely consumed psychoactive drug in the world. Natural sources of caffeine include coffee, tea, and chocolate. Synthetic caffeine is also added to products to promote arousal, alertness, energy, and elevated mood. Over the past decade, the introduction of new caffeine-containing food products, as well as changes in consumption patterns of the more traditional sources of caffeine, has increased scrutiny by health authorities and regulatory bodies about the overall consump...

  19. A Review of the Biochemical and Haematological Effects of Caffeine ...

    African Journals Online (AJOL)

    Caffeine is a xanthine alkaloid that acts as a stimulant drug. It exists naturally in certain plants such as coffee beans, kola nut, tea leaves, cocoa and can be found in different food and drinks which includes; coffee, tea, chocolate, beverages, energy Caffeine is one of the most popularly consumed psychoactive substance in ...

  20. Inhibition of Listeria monocytogenes ATCC 19115 on ham steak by tea bioactive compounds incorporated into chitosan-coated plastic films

    Directory of Open Access Journals (Sweden)

    Vodnar Dan C

    2012-07-01

    Full Text Available Abstract Background The consumer demands for better quality and safety of food products have given rise to the development and implementation of edible films. The use of antimicrobial films can be a promising tool for controlling L. monocytogenes on ready to eat products. The aim of this study was to develop effective antimicrobial films incorporating bioactive compounds from green and black teas into chitosan, for controlling L. monocytogenes ATCC 19115 on vacuum-packaged ham steak. The effectiveness of these antimicrobial films was evaluated at room temperature (20°C for 10 days and at refrigerated temperature (4°C for 8 weeks. Results The HPLC results clearly show that relative concentrations of catechins and caffeine in green tea ranked EGCG>EGC>CAF>ECG>EC>C while in black tea extracts ranked CAF>EGCG>ECG>EGC>EC>C. The chitosan-coated plastic films incorporating green tea and black tea extracts shows specific markers identified by FTIR. Incorporating natural extracts into chitosan showed that the growth of L monocytogenes ATCC 19115 was inhibited. The efficacy of antimicrobial effect of tea extracts incorporated into chitosan-coated plastic film was dose dependent. However, chitosan-coated films without addition of tea extracts did not inhibit the growth of L. monocytogenes ATCC 19115. Chitosan-coated plastic films incorporating 4% Green tea extract was the most effective antimicrobial, reducing the initial counts from 3.2 to 2.65 log CFU/cm2 during room temperature storage and from 3.2 to 1–1.5 log CFU/cm2 during refrigerated storage. Conclusions Incorporation of tea extracts into the chitosan-coated films considerably enhanced their effectiveness against L. monocytogenes ATCC 19115. 4% Green tea incorporated into chitosan-coated plastic film had a better antilisterial effect than 2% green tea or 2% and 4% black tea. Data from this study would provide new formulation options for developing antimicrobial packaging films using tea

  1. Determination and estimation of pharmacokinetic profile of caffeine in form of extract of green tea leaves and its analogy with synthetic form.

    Science.gov (United States)

    Shanmugasundaram, Sangeetha; Manjunatha, N; Vijayan, R; Khatwal, R B; Samanta, M K

    2011-11-01

    The aim of the study was to formulate and investigate the pharmacokinetic parameters for the tablets of herbal extract of caffeine with comparison to synthetic formulation. The tablets of the aqueous herbal extract of leaves of Camellia sinensis and synthetic caffeine were formulated by wet granulation technique. The HPLC and HPTLC were applied as analytical tools for estimation of caffeine. The batches of formulation (B1 to B7) were subjected for various pre and post-formulation studies. The pharmacokinetic of the batch B5 was assessed in rabbits, and the results were compared to synthetic batch B7. With the suitable pre and post-formulation results, the B5 showed in vitro release of 90.54% of caffeine at the end of 60 min. The release followed first order kinetics and the plot of Higuchi and Peppas confirms anomalous diffusion as the basic mechanism behind the release. B5 revealed non-significant mean C(max), t(1/2), and AUC of 1.88 μg/ml, 5.52 h and 9.67 μg.h/ml respectively compared to B7. The study highlights; no significant difference in the pharmacological effect of caffeine when administered in the form of extract. The administration of herbal extract can further provide the other health benefits lacked by synthetic caffeine.

  2. Matcha Green Tea Drinks Enhance Fat Oxidation During Brisk Walking in Females.

    Science.gov (United States)

    Willems, Mark Elisabeth Theodorus; Şahin, Mehmet Akif; Cook, Matthew David

    2018-01-18

    Intake of the catechin epigallocatechin gallate and caffeine has been shown to enhance exercise-induced fat oxidation. Matcha green tea powder contains catechins and caffeine and is consumed as a drink. We examined the effect of Matcha green tea drinks on metabolic, physiological and perceived intensity responses during brisk walking. Thirteen females (age: 27±8 yr, body mass: 65±7 kg, height: 166±6 cm) volunteered. Resting metabolic equivalent (1-MET) was measured using Douglas bags (1-MET: 3.4±0.3 ml·kg -1 ·min -1 ). Participants completed an incremental walking protocol to establish the relationship between walking speed and oxygen uptake and individualize the walking speed at 5- or 6-MET. A randomized cross-over design was used with participants tested between day 9 and 11 of the menstrual cycle (follicular phase). Participants consumed 3 drinks (each drink made with 1 gram of Matcha premium grade, OMGTea Ltd UK) the day before, and 1 drink 2 hours before the 30-min walk at 5- (n=10) or 6-METs (walking speed: 5.8±0.4 km·h -1 ) with responses measured at 8-10, 18-20 and 28-30 min. Matcha had no effect on physiological and perceived intensity responses. Matcha resulted in lower respiratory exchange ratio (control: 0.84±0.04; Matcha: 0.82±0.04) (P drinking can enhance exercise-induced fat oxidation in females. However, when regular brisk walking with 30-min bouts is being undertaken as part of a weight loss program, the metabolic effects of Matcha should not be overstated.

  3. Do leaf surface characteristics affect Agrobacterium infection in tea

    Indian Academy of Sciences (India)

    Caffeine fraction of tea promoted Agrobacterium infection even in leaves poor in wax (Upasi-10), whereas caffeine-free wax inhibited both Agrobacterium growth and infection. Thus, study suggests the importance of leaf surface features in influencing the Agrobacterium infection in tea leaf explants. Our study also provides a ...

  4. Caffeine intake among adolescents in Delhi

    Directory of Open Access Journals (Sweden)

    Mridul Gera

    2016-01-01

    Full Text Available Background: Availability and advertising of caffeinated drinks is on the rise in Indian market. Excess caffeine intake may have deleterious effects on health. Objective: To estimate the daily consumption of caffeine among urban school-going adolescents from Delhi. Materials and Methods: A school-based survey was conducted to determine the amount and pattern of caffeine consumption among students of classes 9-12, using a self-administered questionnaire. Results: Of 300 participants (median age 15 year, 174 boys, 291 (97% were consuming caffeine [mean (SD: 121.0 (98.2 mg/day]. Nineteen (6% students were consuming more than 300 mg of caffeine per day. Tea/coffee contributed to more than 50% of the caffeine intake. The rest was derived from cola beverages, chocolates, and energy drinks. Conclusion: Average caffeine consumption among school-going adolescents from Delhi is high. The findings of this preliminary survey need to be confirmed in larger data sets.

  5. Caffeine Intake Among Adolescents in Delhi.

    Science.gov (United States)

    Gera, Mridul; Kalra, Swati; Gupta, Piyush

    2016-01-01

    Availability and advertising of caffeinated drinks is on the rise in Indian market. Excess caffeine intake may have deleterious effects on health. To estimate the daily consumption of caffeine among urban school-going adolescents from Delhi. A school-based survey was conducted to determine the amount and pattern of caffeine consumption among students of classes 9-12, using a self-administered questionnaire. Of 300 participants (median age 15 year, 174 boys), 291 (97%) were consuming caffeine [mean (SD): 121.0 (98.2) mg/day]. Nineteen (6%) students were consuming more than 300 mg of caffeine per day. Tea/coffee contributed to more than 50% of the caffeine intake. The rest was derived from cola beverages, chocolates, and energy drinks. Average caffeine consumption among school-going adolescents from Delhi is high. The findings of this preliminary survey need to be confirmed in larger data sets.

  6. THE EFFECT OF CAFFEINE ON TEAR FORMATION

    African Journals Online (AJOL)

    INTRODUCTION. Caffeine is a methylxanthine, and be derived form such sources as kola nuts, coffee beans and cocoa. It is contained in most of the things we eat, and drink like chocolates, cola drink, coffee, tea, cocoa, drink and many other beverages,. As stated by Goodman and Gilman , the different sources of caffeine ...

  7. Antidiabetic Effects of Tea

    Directory of Open Access Journals (Sweden)

    Qiu-Yue Fu

    2017-05-01

    Full Text Available Diabetes mellitus (DM is a chronic endocrine disease resulted from insulin secretory defect or insulin resistance and it is a leading cause of death around the world. The care of DM patients consumes a huge budget due to the high frequency of consultations and long hospitalizations, making DM a serious threat to both human health and global economies. Tea contains abundant polyphenols and caffeine which showed antidiabetic activity, so the development of antidiabetic medications from tea and its extracts is increasingly receiving attention. However, the results claiming an association between tea consumption and reduced DM risk are inconsistent. The advances in the epidemiologic evidence and the underlying antidiabetic mechanisms of tea are reviewed in this paper. The inconsistent results and the possible causes behind them are also discussed.

  8. Antidiabetic Effects of Tea.

    Science.gov (United States)

    Fu, Qiu-Yue; Li, Qing-Sheng; Lin, Xiao-Ming; Qiao, Ru-Ying; Yang, Rui; Li, Xu-Min; Dong, Zhan-Bo; Xiang, Li-Ping; Zheng, Xin-Qiang; Lu, Jian-Liang; Yuan, Cong-Bo; Ye, Jian-Hui; Liang, Yue-Rong

    2017-05-20

    Diabetes mellitus (DM) is a chronic endocrine disease resulted from insulin secretory defect or insulin resistance and it is a leading cause of death around the world. The care of DM patients consumes a huge budget due to the high frequency of consultations and long hospitalizations, making DM a serious threat to both human health and global economies. Tea contains abundant polyphenols and caffeine which showed antidiabetic activity, so the development of antidiabetic medications from tea and its extracts is increasingly receiving attention. However, the results claiming an association between tea consumption and reduced DM risk are inconsistent. The advances in the epidemiologic evidence and the underlying antidiabetic mechanisms of tea are reviewed in this paper. The inconsistent results and the possible causes behind them are also discussed.

  9. Safety assessment of green tea based beverages and dried green tea extracts as nutritional supplements.

    Science.gov (United States)

    Dekant, Wolfgang; Fujii, Kenkichi; Shibata, Eiichiro; Morita, Osamu; Shimotoyodome, Akira

    2017-08-05

    The safety of green tea infusions and green tea extract (GTE)-based products is reviewed regarding catechins. Epigallocatechin 3-gallate (EGCG), the major catechin present in green tea, is suspected of being responsible for liver toxicity reported in humans consuming food supplements. Intake of EGCG with green tea infusions and GTE-based beverages is up to about 450mg EGCG/person/day in Europe and higher in Asia. Consumption of green tea is not associated with liver damage in humans, and green tea infusion and GTE-based beverages are considered safe in the range of historical uses. In animal studies, EGCG's potency for liver effects is highly dependent on conditions of administration. Use of NOAELs from bolus administration to derive a tolerable upper intake level applying the margin of safety concept results in acceptable EGCG-doses lower than those from one cup of green tea. NOAELs from toxicity studies applying EGCG with diet/split of the daily dose are a better point of departure for risk characterization. In clinical intervention studies, liver effects were not observed after intakes below 600mg EGCG/person/day. Thus, a tolerable upper intake level of 300mg EGCG/person/day is proposed for food supplements; this gives a twofold safety margin to clinical studies that did not report liver effects and a margin of safety of 100 to the NOAELs in animal studies with dietary administration of green tea catechins. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Both phenolic and non-phenolic green tea fractions inhibit migration of cancer cells

    Science.gov (United States)

    Green tea consumption is associated with chemoprevention of many cancer types. Fresh tea leaves are rich in polyphenolic catechins, which can constitute up to 30% of the dry leaf weight. While the polyphenols of green tea have been well investigated, it is still largely unknown, whether or not non-p...

  11. Facile synthesis of amine-functional reduced graphene oxides as modified quick, easy, cheap, effective, rugged and safe adsorbent for multi-pesticide residues analysis of tea.

    Science.gov (United States)

    Ma, Guicen; Zhang, Minglu; Zhu, Li; Chen, Hongping; Liu, Xin; Lu, Chengyin

    2018-01-05

    Amine-functional reduced graphene oxide (amine-rGO) with different carbon chain length amino groups were successfully synthesized. The graphene oxides (GO) reduction as well as amino grafting were achieved simultaneously in one step via a facile solvothermal synthetic strategy. The obtained materials were characterized by X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectrometry and X-ray photoelectron spectroscopy to confirm the modification of GO with different amino groups. The adsorption performance of catechins and caffeine from tea acetonitrile extracts on different amine functional rGO samples were evaluated. It was found that tributylamine-functional rGO (tri-BuA-rGO) exhibited the highest adsorption ability for catechins and caffeine compared to GO and other amino group functional rGO samples. It was worth to note that the adsorption capacity of catechins on tri-BuA-rGO was 11 times higher than that of GO (203.7mgg -1 vs 18.7mgg -1 ). Electrostatic interaction, π-π interaction and surface hydrophilic-hydrophobic properties of tri-BuA-rGO played important roles in the adsorption of catechins as well as caffeine. The gravimetric analysis confirmed that the tri-BuA-rGO achieved the highest efficient cleanup preformance compared with traditional dispersive solid phase extraction (dSPE) adsorbents like primary-secondary amine (PSA), graphitized carbon black (GCB) or C18. A multi-pesticides analysis method based on tri-BuA-rGO is validated on 33 representative pesticides in tea using gas chromatography coupled to tandem mass spectrometry or high-performance liquid chromatography coupled with tandem mass spectrometry. The analysis method gave a high coefficient of determination (r 2 >0.99) for each pesticide and satisfactory recoveries in a range of 72.1-120.5%. Our study demonstrated that amine functional rGO as a new type of QuEChERS adsorbent is expected to be widely applied for analysis of pesticides at trace levels. Copyright © 2017

  12. Antiviral effects of green tea ( Camellia sinensis ) against pathogenic ...

    African Journals Online (AJOL)

    Background: Tea is the second most addictive worldwide after formulations containing caffeine in carbonated beverage. Green tea is made from leaves of the Camellia sinensis plant. In the repertoire of traditional Chinese medicine, green tea beverages have played a fundamental role associated with their culture.

  13. Coffee, tea and melanoma risk : findings from the European Prospective Investigation into Cancer and Nutrition

    NARCIS (Netherlands)

    Caini, Saverio; Masala, Giovanna; Saieva, Calogero; Kvaskoff, Marina; Savoye, Isabelle; Sacerdote, Carlotta; Hemmingsson, Oskar; Hammer Bech, Bodil; Overvad, Kim; Tjønneland, Anne; Petersen, Kristina E N; Mancini, Francesca Romana; Boutron-Ruault, Marie Christine; Cervenka, Iris; Kaaks, Rudolf; Kühn, Tilman; Boeing, Heiner; Floegel, Anna; Trichopoulou, Antonia; Valanou, Elisavet; Kritikou, Maria; Tagliabue, Giovanna; Panico, Salvatore; Tumino, Rosario; Bueno-de-Mesquita, H. Bas; Peeters, Petra H.; Veierød, Marit B.; Ghiasvand, Reza; Lukic, Marko; Quirós, José Ramón; Chirlaque, Maria Dolores; Ardanaz, Eva; Salamanca Fernández, Elena; Larrañaga, Nerea; Zamora-Ros, Raul; Maria Nilsson, Lena; Ljuslinder, Ingrid; Jirström, Karin; Sonestedt, Emily; Key, Timothy J.; Wareham, Nick; Khaw, Kay Tee; Gunter, Marc; Huybrechts, Inge; Murphy, Neil; Tsilidis, Konstantinos K.; Weiderpass, Elisabete; Palli, Domenico

    2017-01-01

    In vitro and animal studies suggest that bioactive constituents of coffee and tea may have anticarcinogenic effects against cutaneous melanoma; however, epidemiological evidence is limited to date. We examined the relationships between coffee (total, caffeinated or decaffeinated) and tea consumption

  14. Does caffeine affect cardiovascular responses?

    NARCIS (Netherlands)

    S. Bradamante; L. Barenghi (Livia); S. Versari (Silvia); A. Villa (Alessandro); J.W. de Jong (Jan Willem)

    2007-01-01

    textabstractCaffeine (1,3,7-trimethylxanthine), a natural alkaloid present in many beverages such as coffee, tea and cola drinks, is the most widely consumed pharmacological compound. Due to its common use and frequent intake in stressful conditions, a great deal of data have been produced by

  15. Caffeine Enhances the Calcium-Dependent Cardiac Mitochondrial Permeability Transition: Relevance for Caffeine Toxicity

    OpenAIRE

    Sardão, Vilma A.; Oliveira, Paulo J.; Moreno, António J. M.

    2002-01-01

    Caffeine (1,3,7-trimethylxanthine), a compound present in beverages such as tea and coffee, is known to be toxic at high concentrations. Some of the observed clinical conditions include cardiovascular disease and reproductive disorders, among others. The possible toxic effects of caffeine on heart mitochondria are still poorly understood. The influence of caffeine on the mitochondrial permeability transition has not been clarified so far. The objective of this study was to investigate whether...

  16. Cancer Therapy by Catechins Involves Redox Cycling of Copper Ions and Generation of Reactive Oxygen Species

    Directory of Open Access Journals (Sweden)

    Mohd Farhan

    2016-02-01

    Full Text Available Catechins, the dietary phytochemicals present in green tea and other beverages, are considered to be potent inducers of apoptosis and cytotoxicity to cancer cells. While it is believed that the antioxidant properties of catechins and related dietary agents may contribute to lowering the risk of cancer induction by impeding oxidative injury to DNA, these properties cannot account for apoptosis induction and chemotherapeutic observations. Catechin (C, epicatechin (EC, epigallocatechin (EGC and epigallocatechin-3-gallate (EGCG are the four major constituents of green tea. In this article, using human peripheral lymphocytes and comet assay, we show that C, EC, EGC and EGCG cause cellular DNA breakage and can alternatively switch to a prooxidant action in the presence of transition metals such as copper. The cellular DNA breakage was found to be significantly enhanced in the presence of copper ions. Catechins were found to be effective in providing protection against oxidative stress induced by tertbutylhydroperoxide, as measured by oxidative DNA breakage in lymphocytes. The prooxidant action of catechins involved production of hydroxyl radicals through redox recycling of copper ions. We also determined that catechins, particularly EGCG, inhibit proliferation of breast cancer cell line MDA-MB-231 leading to a prooxidant cell death. Since it is well established that tissue, cellular and serum copper levels are considerably elevated in various malignancies, cancer cells would be more subject to redox cycling between copper ions and catechins to generate reactive oxygen species (ROS responsible for DNA breakage. Such a copper dependent prooxidant cytotoxic mechanism better explains the anticancer activity and preferential cytotoxicity of dietary phytochemicals against cancer cells.

  17. Survey of caffeine levels in retail beverages in Portugal

    OpenAIRE

    Pena, A.; Lino, C.; Silveira, M. I. N.

    2005-01-01

    The caffeine content of 85 retail beverage samples purchased from local supermarkets between 1995 and 2004 was determined. The potential intake of caffeine through the consumption of these beverages (but excluding coffee) was estimated for students of the University of Coimbra, Portugal. The caffeine content of the beverages ranged from 47.5 to 282.5?mg?l-1 for teas, from 20.1 to 47.2?mg?l-1 for tea extracts samples, and from 80.7 to 168.7?mg?l-1 for cola soft drinks. Caffeine was not complet...

  18. Acute effects of theanine, caffeine and theanine-caffeine combination on attention.

    Science.gov (United States)

    Kahathuduwa, Chanaka N; Dassanayake, Tharaka L; Amarakoon, A M Tissa; Weerasinghe, Vajira S

    2017-07-01

    l-theanine is a constituent of tea which is claimed to enhance cognitive functions. We aimed to determine whether theanine and theanine-caffeine combination have acute positive effects on cognitive and neurophysiological measures of attention, compared to caffeine (a positive control) and a placebo in healthy individuals. In a placebo-controlled, five-way crossover trial in 20 healthy male volunteers, we compared the effects of l-theanine (200 mg), caffeine (160 mg), their combination, black tea (one cup) and a placebo (distilled water) on cognitive (simple [SVRT] and recognition visual reaction time [RVRT]) and neurophysiological (event-related potentials [ERPs]) measures of attention. We also recorded visual (VEPs) and motor evoked potentials (MEPs) to examine any effects of treatments on peripheral visual and motor conduction, respectively. Mean RVRT was significantly improved by theanine (P = 0.019), caffeine (P = 0.043), and theanine-caffeine combination (P = 0.001), but not by tea (P = 0.429) or placebo (P = 0.822). VEP or MEP latencies or SVRT did not show significant inter-treatment differences. Theanine (P = 0.001) and caffeine (P = 0.001) elicited significantly larger mean peak-to-peak N2-P300 ERP amplitudes than the placebo, whereas theanine-caffeine combination elicited a significantly larger mean N2-P300 amplitude than placebo (P caffeine (P = 0.005). No significant theanine × caffeine interaction was observed for RVRT or N2-P300 amplitude. A dose of theanine equivalent of eight cups of back tea improves cognitive and neurophysiological measures of selective attention, to a degree that is comparable with that of caffeine. Theanine and caffeine seem to have additive effects on attention in high doses.

  19. Coffee, tea, colas, and risk of epithelial ovarian cancer.

    Science.gov (United States)

    Song, Yoon Ju; Kristal, Alan R; Wicklund, Kristine G; Cushing-Haugen, Kara L; Rossing, Mary Anne

    2008-03-01

    Associations of coffee, tea, and other caffeinated beverages with ovarian cancer risk remain uncertain. In a population-based study in Washington State, 781 women with epithelial ovarian cancer diagnosed in 2002 to 2005 and 1,263 controls completed self-administered questionnaires detailing consumption of caffeinated and noncaffeinated coffee, teas, and colas and in-person interviews regarding reproductive and hormonal exposures. We assessed risk associated with coffee, tea, and cola drinking and with total caffeine consumption using logistic regression to calculate odds ratios and 95% confidence intervals. Neither caffeinated nor decaffeinated coffees were associated with ovarian cancer risk; also, we observed no association of total caffeine with risk using a combined index that summed intake from coffee, tea, and carbonated soft drinks. Among teas, neither herbal/decaffeinated nor black teas were associated with risk; however, women who reported drinking >or=1 cup/d of green tea had a 54% reduction in risk (P trend = 0.01). Associations of green tea with risk were similar when invasive and borderline cases were considered separately and when Asian women were excluded from analysis. Green tea, which is commonly consumed in countries with low ovarian cancer incidence, should be further investigated for its cancer prevention properties.

  20. A Literature Review of Some Deseases Can Cured With Tea Component

    OpenAIRE

    Tuti Anggraini

    2013-01-01

    Tea (Camellia sinensis) very rich in flavonoids and one of the important plant in the world. The six major flavan-3-ols occurring in tea are catechin (C), gallocatechin (GC), epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (EGG), and epigallocatechin-3-gallate (EGCG). Theaflavins and thearubigins are a group of polyphenol pigments formed during the fermentation of black tea This paper identified the deaseas can cured with the tea properties by literature reviewed. Besides the ...

  1. Caffeine's Vascular Mechanisms of Action

    Directory of Open Access Journals (Sweden)

    Darío Echeverri

    2010-01-01

    Full Text Available Caffeine is the most widely consumed stimulating substance in the world. It is found in coffee, tea, soft drinks, chocolate, and many medications. Caffeine is a xanthine with various effects and mechanisms of action in vascular tissue. In endothelial cells, it increases intracellular calcium stimulating the production of nitric oxide through the expression of the endothelial nitric oxide synthase enzyme. Nitric oxide is diffused to the vascular smooth muscle cell to produce vasodilation. In vascular smooth muscle cells its effect is predominantly a competitive inhibition of phosphodiesterase, producing an accumulation of cAMP and vasodilation. In addition, it blocks the adenosine receptors present in the vascular tissue to produce vasoconstriction. In this paper the main mechanisms of action of caffeine on the vascular tissue are described, in which it is shown that caffeine has some cardiovascular properties and effects which could be considered beneficial.

  2. Tea polyphenols dominate the short-term tea (Camellia sinensis) leaf litter decomposition.

    Science.gov (United States)

    Fan, Dong-Mei; Fan, Kai; Yu, Cui-Ping; Lu, Ya-Ting; Wang, Xiao-Chang

    Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols.

  3. Tea polyphenols dominate the short-term tea (Camellia sinensis) leaf litter decomposition*

    Science.gov (United States)

    Fan, Dong-mei; Fan, Kai; Yu, Cui-ping; Lu, Ya-ting; Wang, Xiao-chang

    2017-01-01

    Polyphenols are one of the most important secondary metabolites, and affect the decomposition of litter and soil organic matter. This study aims to monitor the mass loss rate of tea leaf litter and nutrient release pattern, and investigate the role of tea polyphenols played in this process. High-performance liquid chromatography (HPLC) and classical litter bag method were used to simulate the decomposition process of tea leaf litter and track the changes occurring in major polyphenols over eight months. The release patterns of nitrogen, potassium, calcium, and magnesium were also determined. The decomposition pattern of tea leaf litter could be described by a two-phase decomposition model, and the polyphenol/N ratio effectively regulated the degradation process. Most of the catechins decreased dramatically within two months; gallic acid (GA), catechin gallate (CG), and gallocatechin (GC) were faintly detected, while others were outside the detection limits by the end of the experiment. These results demonstrated that tea polyphenols transformed quickly and catechins had an effect on the individual conversion rate. The nutrient release pattern was different from other plants which might be due to the existence of tea polyphenols. PMID:28124839

  4. Recent patents on antibacterial, antifungal and antiviral properties of tea.

    Science.gov (United States)

    Yiannakopoulou, Eugenia Ch

    2012-04-01

    Teas have beneficial effects on human health including cardioprotective, anticarcinogenic, antibacterial, antiviral and antifungal activity. The precise antimicrobial spectrum of tea is difficult to be defined due to variation in the methods of testing that have been used. Antibacterial effects of tea have been demonstrated against a number of microorganisms including Staphylococcus aureus, Vibrio cholerae, Escherichia coli, Shigella spp., Salmonella spp., Bacillus spp., Klebsiella spp. and Pseudomonas aeruginosa. Teas and tea ingredients seem to have both bactericidal and bacteriostatic actions. In addition, tea catechins have been shown to modify the antibiotic sensitivity of bacteria and to alter the expression of factors that determine bacterial virulence. Antiviral effects of green tea have been demonstrated against the influenza virus, as well as against the Herpes simplex virus, tobacco mosaic virus, enterovirus, rotavirus, Epstein Barr virus, HIV virus. Yet, green tea catechins have been shown to have antiviral activities against HIV infection. Antifungal effects of tea have been reported against Candida albicans, Trichophyton mentagrophytes, and Trichophyton rubrum. The present paper describes recent patents on antimicrobial effect of teas and tea ingredients.

  5. Spontaneously Assembled Nano-aggregates in Clear Green Tea Infusions from Camellia ptilophylla and Camellia sinensis.

    Science.gov (United States)

    Lin, Xiaorong; Gao, Xiong; Chen, Zhongzheng; Zhang, Yuanyuan; Luo, Wei; Li, Xiaofei; Li, Bin

    2017-05-10

    Tea nano-aggregates spontaneously assembled in clear tea infusions are considered as the precursors of tea cream, although their molecular basis remains obscure. Here, we characterized nano-aggregates in green tea infusions from Camellia ptilophylla, a peculiar tea variety with 6.0% of theobromine, and Camellia sinensis as the control for comparative purpose. Numerous negatively charged spherical colloidal particles of 50-100 nm in diameter were primarily found in both green tea infusions. Catechins, proteins, and carbohydrates were confirmed as the dominant components in green tea nano-aggregates. In addition, iron, copper, nickel, proteins, and gallated catechins exhibited higher aggregating affinity than other components, whereas methylxanthines and calcium contributed to the transformation of nano-aggregates into tea cream. Green tea nano-aggregates were partly destroyed by simulated gastrointestinal digestion, and removing theses peculiar particles dramatically attenuated the bioaccessibility of methylxanthines, theanine, and some catechin monomers in green tea infusions. This study enhanced our knowledge of molecular interactions in the formation of green tea cream and provided insight into physicochemical profiles, phytochemical nature, and functional effects of green tea nano-aggregates.

  6. Caffeine overdose

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/002579.htm Caffeine overdose To use the sharing features on this page, please enable JavaScript. Caffeine is a substance that exists naturally in certain ...

  7. In vitro activity of 23 tea extractions and epigallocatechin gallate against Candida species

    DEFF Research Database (Denmark)

    Chen, Ming; Zhai, Lin; Arendrup, Maiken Cavling

    2015-01-01

    In this study, we investigate the susceptibility of Candida albicans, Candida glabrata, Candida krusei, Candida parapsilosis, Candida tropicalis, and Aspergillus fumigatus using the EUCAST microdilution minimum inhibitory concentration (MIC) method (final tea supernatant concentration range 5.......0-0.005 mg/ml) to 23 different teas and tea catechins including epigallocatechin gallate (EGCG) isolated from green tea. All teas exhibited potent in vitro antifungal activity against C. glabrata. Six out of nine green teas and three of eight black teas had an MIC of 0.078 mg/ml, one white tea had an MIC...... of 0.156 mg/ml, and finally three of five oolong teas had an MIC of 0.156 mg/ml. Three teas exhibited activity against C. albicans (MIC 1.25 mg/ml), one green tea was active against C. parapsilosis (MIC 1.25 mg/ml), but none were effective against C. krusei, C. tropicalis or A. fumigatus...

  8. Microbial Succession and the Dynamics of Chemical Compounds during the Solid-State Fermentation of Pu-erh Tea

    Directory of Open Access Journals (Sweden)

    Yan Ma

    2017-02-01

    Full Text Available An in-depth knowledge of the microbiota and metabolites in the solid-state fermentation (SSF of Post-fermented Pu-erh tea (Pu-erh Shucha, PFPT, a Chinese traditional tea with various health benefits, is essential to develop modern fermentation technology. In this work, the microbial diversity and succession in two laboratory-developed SSF protocols for PFPT were investigated using pyrosequencing analyses of the bacterial 16S rRNA and fungal 18S rRNA genes. The active bacteria in the initial stages of SSF (seven days were from the raw materials and environment, with a dominance of Proteobacteria in both the raw materials and SSF after seven days. The environmental bacteria were inoculated into the tea mass throughout the fermentation process and multiplied, with a dominance of Firmicutes at day 14 and 21, and then Firmicutes and Actinobacteria at the last stages of fermentation (day 28 and 35. The dominant fungi came from the raw material and were identified at the genus level as Aspergillus throughout the SSF process. The contents of tea polyphenols, free amino acids, gallic acid, theaflavin, thearubigin, and catechins decreased significantly (p < 0.05, while the level of theabrownin increased significantly (p < 0.05. The caffeine content showed no significant change (p > 0.05. In total, 30 bacterial and three fungal genera showed significant correlations to 1–8 and 3–4 identified tea compounds, respectively (p < 0.05. The dynamics of the microbiota and chemical compounds, and correlations between their changes in the SSF of PFPT were revealed, and present a foundation for further studies on the microbial effects on chemical compounds.

  9. Analysis of Caffeine in Beverages Using Aspirin as a Fluorescent Chemosensor

    Science.gov (United States)

    Smith, Jordan; Loxley, Kristen; Sheridan, Patrick; Hamilton, Todd M.

    2016-01-01

    Caffeine (1,3,7-trimethylxanthine) is an alkaloid stimulant that is popular in beverages. Fluorescence-coupled methods have been used to measure the caffeine content in coffee, tea, soft drinks, energy drinks, and cosmetics. In this experiment, we have developed a method for detecting caffeine in beverages utilizing the effect of the caffeine…

  10. Trends in Caffeine Intake Among US Children and Adolescents

    Science.gov (United States)

    Branum, Amy M.; Rossen, Lauren M.; Schoendorf, Kenneth C.

    2016-01-01

    BACKGROUND AND OBJECTIVE Physicians and policy makers are increasingly interested in caffeine intake among children and adolescents in the advent of increasing energy drink sales. However, there have been no recent descriptions of caffeine or energy drink intake in the United States. We aimed to describe trends in caffeine intake over the past decade among US children and adolescents. METHODS We assessed trends and demographic differences in mean caffeine intake among children and adolescents by using the 24-hour dietary recall data from the 1999–2010 NHANES. In addition, we described the proportion of caffeine consumption attributable to different beverages, including soda, energy drinks, and tea. RESULTS Approximately 73% of children consumed caffeine on a given day. From 1999 to 2010, there were no significant trends in mean caffeine intake overall; however, caffeine intake decreased among 2- to 11-year-olds (P caffeine intake, but this contribution declined from 62% to 38% (P caffeine intake in 1999–2000 but increased to nearly 24% of intake in 2009–2010 (P Energy drinks did not exist in 1999–2000 but increased to nearly 6% of caffeine intake in 2009–2010. CONCLUSIONS Mean caffeine intake has not increased among children and adolescents in recent years. However, coffee and energy drinks represent a greater proportion of caffeine intake as soda intake has declined. These findings provide a baseline for caffeine intake among US children and young adults during a period of increasing energy drink use. PMID:24515508

  11. Catechin secretion and phytotoxicity: Fact not fiction.

    Science.gov (United States)

    Bais, Harsh P; Kaushik, Shail

    2010-09-01

    Research indicates that the invasiveness of Centaurea stoebe is attributed to the stronger allelopathic effects on the native North American species than on the related European species, which is one of the unquestionable aspects of the "novel weapons hypothesis (NWH)." Studies originating from controlled to field conditions have shown that C. stoebe utilizes its biochemical potential to exert its invasiveness. The roots of C. stoebe secrete a potent phytotoxin, catechin, which has a detrimental effect on the surrounding plant species. Although, studies on catechin secretion and phytotoxicity represent one of the most well studied systems describing negative plant-plant interactions, it has also sparked controversies lately due to its phytotoxicity dosages and secretion effluxes. Previous reports negate the phytotoxic and pro-oxidant nature of catechin.1-3 In our recent study we have shown that catechin is highly phytotoxic against Arabidopsis thaliana and Festuca idahoensis. We also show that (±) catechin applied to roots of A. thaliana induces reactive oxygen species (ROS) confirming the pro-oxidant nature of catechin. In addition, activation of signature cell death genes such as acd2 and cad1 post catechin treatment in A. thaliana ascertains the phytotoxic nature of catechin.

  12. Effects of Tea Phenolics on Iron Uptake from Different Fortificants by Caco-2 cells

    Science.gov (United States)

    The in vitro effects of tea phenolics on Fe uptake from different fortificants (FeSO4, FeCl3, FeEDTA) by Caco-2 cells were compared. Cell cultures were exposed to catechin, tannic acid, green or black tea solutions added within Fe-containing solution, or used to pre-treat cell cultures before Fe-exp...

  13. Consumption of black tea and cancer risk : a prospective cohort study

    NARCIS (Netherlands)

    Goldbohm, R.A.; Hertog, M.G.L.; Brants, H.A.M.; Poppel, G. van; Brandt, P.A. van den

    1996-01-01

    Background: Tea is one of the most frequently consumed beverages in the world. Antioxidant polyphenol compounds (such as catechins and flavonols) are abundantly present in both green and black teas and have been observed to have anticarcinogenic properties in cell and animal model studies. In black

  14. Green tea phytocompounds as anticancer: A review

    Directory of Open Access Journals (Sweden)

    Najeeb Ullah

    2016-04-01

    Full Text Available Green tea is universally considered significant and its benefits have been experimentally explored by researchers and scientists. Anticancer potential of green tea has been completely recognized now. Green tea contains anti-cancerous constituents and nutrients that have powerful remedial effects. By using electronic data base (1998–2015, different compounds in green tea possessing anticancer activity including epigallocatechin-3-gallate, paclitaxel and docetaxel combinations, ascorbic acid, catechins, lysine, synergistic arginine, green tea extract, proline, and green tea polyphenols has been reported. Green tea extracts exhibited remedial potential against cancer of lung, colon, liver, stomach, leukemic cells, prostate, breast, human cervical cells, head, and neck. For centuries, green tea has been utilized as medicine for therapeutic purposes. It originated in China and extensively used in Asian countries for blood pressure depression and as anticancer medicine. Green tea has therapeutic potential against many diseases such as lowering of blood pressure, Parkinson’s disease, weight loss, esophageal disease, skin-care, cholesterol, Alzheimer’s disease and diabetes.

  15. Does caffeine affect cardiovascular responses?

    OpenAIRE

    Bradamante, S.; Barenghi, Livia; Versari, Silvia; Villa, Alessandro; Jong, Jan Willem

    2007-01-01

    textabstractCaffeine (1,3,7-trimethylxanthine), a natural alkaloid present in many beverages such as coffee, tea and cola drinks, is the most widely consumed pharmacological compound. Due to its common use and frequent intake in stressful conditions, a great deal of data have been produced by epidemiological surveys and experimental mammal studies to evaluate its direct and side effects on the cardiovascular system. There are controversies concerning the possible adverse effects induced by th...

  16. Tea and Health: Studies in Humans

    Science.gov (United States)

    Khan, Naghma; Mukhtar, Hasan

    2014-01-01

    Tea, next to water is the cheapest beverage humans consume. Drinking the beverage tea has been considered a health-promoting habit since ancient times. The modern medicinal research is providing a scientific basis for this belief. The evidence supporting the health benefits of tea drinking grows stronger with each new study that is published in the scientific literature. Tea plant Camellia sinensis has been cultivated for thousands of years and its leaves have been used for medicinal purposes. Tea is used as a popular beverage worldwide and its ingredients are now finding medicinal benefits. Encouraging data showing cancer-preventive effects of green tea from cell-culture, animal and human studies have emerged. Evidence is accumulating that black tea may have similar beneficial effects. Tea consumption has also been shown to be useful for prevention of many debilitating human diseases that include maintenance of cardiovascular and metabolic health. Various studies suggest that polyphenolic compounds present in green and black tea are associated with beneficial effects in prevention of cardiovascular diseases, particularly of atherosclerosis and coronary heart disease. In addition, anti-aging, antidiabetic and many other health beneficial effects associated with tea consumption are described. Evidence is accumulating that catechins and theaflavins, which are the main polyphenolic compounds of green and black tea, respectively, are responsible for most of the physiological effects of tea. This article describes the evidences from clinical and epidemiological studies in the prevention of chronic diseases like cancer and cardiovascular diseases and general health promotion associated with tea consumption. PMID:23448443

  17. Simultaneous Separation and Purification of Tea Bioactives from summer Green Tea by Column Chromatography

    International Nuclear Information System (INIS)

    Zhang, X.; Lei, S.C.; Sun, B.H.; ZENG, X.X.

    2013-01-01

    In the present study, feasibility of producing high quality of tea polyphenols, the anine and caffeine from the extract of summer green tea by column chromatography was investigated. Crude extract of summer green tea obtained by hot water extraction was passed through columns of polyamide and NKA-II macroporous resin respectively, resulting in tea polyphenols-enriched fraction (96.27 +- 1.78%), the anine-enriched fraction (99.02 +- 0.43%) and caffeine-enriched fraction (99.25 +- 0.36%). The recovery rates for tea polyphenols, the anine and caffeine were 72.42 +- 1.41%, 66.12 +- 1.66% and 62.07 +- 2.17%, respectively. The separation procedure allowed the production of such products by decreasing impurities and avoiding the use of poisonous organic solvent. The results suggested that it was possible to produce high-quality products of rich-in tea polyphenols, the anine and caffeine by a simple way. From industrial point of view, this novel method has many merits such as high efficiency of separation, low consumption of energy and environment-friendly procedure. (author)

  18. Effect of catechins on fattening performance, meat quality, some antioxidant and blood parameters and fattening costs in Japanese quail (Coturnix coturnix japonica).

    Science.gov (United States)

    Kara, K; Şentürk, M; Guclu, B K; Sariözkan, S; Eren, M

    2016-08-01

    The aim of this study was to investigate the effect of dietary supplementation of green tea (Camellia sinensis) catechins in quail (Coturnix coturnix japonica). Quail were fed with a basal diet, and the treatment groups were fed on the basal diet with 1.25 or 2.50 g/kg catechin supplementation for 30 d. Fattening performance and meat quality of the quail were estimated. Serum total antioxidant status (TAS), plasma and liver malondialdehyde (MDA) and some serum biochemical parameters were measured. The results showed that catechin supplementation did not affect live weight, feed intake, feed conversion ratio, carcass weight, carcass dressing or the nutrient composition of breast and thigh meats. The water holding capacity (WHC) of breast meat was increased in the 2.50 g/kg catechin treatment. Catechin supplementation increased the serum TAS, but decreased plasma MDA and liver MDA concentration as well as serum glucose and total cholesterol levels. Serum triglyceride and total protein levels were not affected by catechin supplementation. In conclusion, catechins have effective antioxidant hypoglycaemic and hypocholesterolaemic properties, as well as having the potential to increase meat quality in fattening quail. On the other hand, catechin supplementation did not have any negative effect on the fattening performance, meat nutrient composition and fattening costs in fattening quail.

  19. Study of nutritional value of dried tea leaves and infusions of black, green and white teas from Chinese plantations

    Science.gov (United States)

    Czernicka, Maria; Zaguła, Grzegorz; Bajcar, Marcin; Saletnik, Bogdan; Puchalski, Czesław

    The processing of tea leaves determines the contents of bioactive ingredients, hence it should be expected that each variety of tea, black, red or green, will represent a different package of compounds of physiological importance. Taste and aroma, as well as price and brand are the main factors impacting consumers’ preferences with regard to tea of their choice; on the other hand consumers less frequently pay attention to the chemical composition and nutritional value of tea. The purpose of the study was assessment of the nutritional value of black, green and white high-quality tea leaf from Chinese plantations based on the chemical composition of the dried leaves as well as minerals and caffeine content in tea infusions. The research material included 18 high-quality loose-leaf teas produced at Chinese plantations, imported to Poland, and purchased in an online store. The analyses included examination of the dried tea leaves for their chemical composition (contents of water, protein, volatile substances and ash) and assessment of selected minerals and caffeine contents in the tea infusions. High-quality Chinese green teas were found with the most valuable composition of minerals, i.e. the highest contents of Zn, Mn, Mg, K, Ca and Al and the highest contents of protein in comparison to the other products. Chinese black teas had the highest contents of total ash and caffeine and white teas were characterized with high content of volatile substances, similar to the black teas, and the highest content of water and the lowest content of total ash. The three types of tea brews examined in the present study, in particular green tea beverages, significantly enhance the organism’s mineral balance by providing valuable elements

  20. Mother's Caffeine Ingestion Affects Fecundity and Offspring Birth Weight in Murine Models

    OpenAIRE

    O. Owolabi Joshua; Adeyeye Joshua; O. Oyewumi Samson

    2017-01-01

    Caffeine is the world most popularly consumed legal neurostimulant. It is naturally found in beverage drinks including coffee and tea. It is also artificially added to several soft and energy drinks, as well as medicinal drugs including analgesics. Caffeine itself can be employed for therapeutic purposes. The wide range of caffeine distribution in substances and its popularity in some cultures makes it almost impossible to regulate its consumption. Several people consume caffeine from one or ...

  1. Energy drinks and the neurophysiological impact of caffeine.

    Science.gov (United States)

    Persad, Leeana Aarthi Bagwath

    2011-01-01

    Caffeine is the most widely used psychoactive stimulant with prevalent use across all age groups. It is a naturally occurring substance found in the coffee bean, tea leaf, the kola nut, cocoa bean. Recently there has been an increase in energy drink consumption leading to caffeine abuse, with aggressive marketing and poor awareness on the consequences of high caffeine use. With caffeine consumption being so common, it is vital to know the impact caffeine has on the body, as its effects can influence cardio-respiratory, endocrine, and perhaps most importantly neurological systems. Detrimental effects have being described especially since an over consumption of caffeine has being noted. This review focuses on the neurophysiological impact of caffeine and its biochemical pathways in the human body.

  2. Energy drinks and the neurophysiological impacts of caffeine

    Directory of Open Access Journals (Sweden)

    Leeana eBagwath Persad

    2011-10-01

    Full Text Available Caffeine is the most widely used psychoactive stimulant with prevalent use across all age groups. It is a naturally occurring substance found in the coffee bean, tea leaf, the kola nut, cocoa bean. Recently there has been an increase in energy drink consumption leading to caffeine abuse, with aggressive marketing and poor awareness on the consequences of high caffeine use. With caffeine consumption being so common, it is vital to know the impact caffeine has on the body, as its effects can influence cardio-respiratory, endocrine and perhaps most importantly neurological systems. Detrimental effects have being described especially since an over consumption of caffeine has being noted. This review focuses on the neurophysiological impact of caffeine and its biochemical pathways in the human body.

  3. Soxhlet Extraction of Caffeine from Beverage Plants

    Science.gov (United States)

    Adam, D. J.; Mainwaring, J.; Quigley, Michael N.

    1996-12-01

    A simple procedure is described for the extraction of caffeine from coffee beans or granules, tea leaves, mat leaves, etc. Since dichloromethane and several other hazardous substances are used, the procedure is best performed in a fume hood. Following extraction, melting point determination of the crystalline precipitate establishes its positive identity. Includes 33 references.

  4. Determinação simultânea de teobromina, teofilina e cafeína em chás por cromatografia líquida de alta eficiência Simultaneous determination of theobromine, theophylline and caffeine in teas by high performance liquid chromatography

    Directory of Open Access Journals (Sweden)

    Adriana Barreto Alves

    2002-06-01

    Full Text Available Para a realização deste trabalho, foram analisadas 10 amostras de diferentes tipos e marcas de chás com o objetivo de se quantificar teobromina, teofilina e cafeína simultaneamente. Para tanto, otimizou-se técnica de cromatografia líquida de alta eficiência (CLAE baseada na ISO 10095 (1992, utilizando-se coluna Inertsil ODS-3 (150x4 mm, 5 mm, fase móvel de ácido acético 1% + acetonitrila (95:5, v/v, fluxo de 1 mL/min e detector de UV/VIS ajustado em 273 nm. Os resultados de cafeína obtidos por esse método foram comparados com os obtidos por um método espectrofotométrico de acordo com Schormüller (1970. Não houve diferença significativa nos resultados de cafeína nas amostras de chá preto obtidos pelos dois métodos. As amostras de chá preto foram as que apresentaram maiores teores de teobromina e cafeína e nenhuma das amostras apresentou quantidades significativas de teofilina.To carry out this study, 10 samples of different kinds and brands of teas were analyzed with the purpose of quantifying simultaneously theobromine, theophylline and caffeine. For this, high performance liquid chromatography (HPLC was used based on ISO 10095 (1992. The conditions were: a reversed phase column (Inertisil ODS-3, 150x4 mm, 5 mm; acetic acid 1% + acetonitrile (95:5, v/v as mobile phase; flow of 1 ml/min and UV-VIS detector set at 273 nm. The results of caffeine obtained by this method were compared with those using a spectrophotometric method according to Schormüller (1970. In the case of black tea, no difference was observed in the caffeine, by both methods. The samples of black tea had the highest amounts of theobromine and caffeine and no sample had a significant amount of theophylline.

  5. Green tea and the risk of prostate cancer: A systematic review and meta-analysis.

    Science.gov (United States)

    Guo, Yuming; Zhi, Fan; Chen, Ping; Zhao, Keke; Xiang, Han; Mao, Qi; Wang, Xinghuan; Zhang, Xinhua

    2017-03-01

    Prostate cancer (PCa) now remains the 2nd most frequently diagnosed cancer. In recent years, chemoprevention for PCa becomes a possible concept. Especially, many phytochemicals rich foods are suggested to lower the risk of cancer. Among these foods, green tea is considered as effective prevention for various cancers. However, clinical trials and previous meta-analyses on the relationship between green tea consumption and the risk of PCa have produced inconsistent outcomes. This study aims to determine the dose-response association of green tea intake with PCa risk and the preventive effect of green tea catechins on PCa risk. Seven observational studies and 3 randomized controlled trials were retrieved from Cochrane Library, PubMed, Sciencedirect Online, and hand searching. The STATA (version 12.0) was applied to analyze the data. The relative risks (RRs) and 95% confidence intervals were pooled by fixed or random effect modeling. Dose-response relations were evaluated with categories of green tea intake. Although there was no statistical significance in the comparison of the highest versus lowest category, there was a trend of reduced incidence of PCa with each 1 cup/day increase of green tea (P = 0.08). Our dose-response meta-analysis further demonstrated that higher green tea consumption was linearly associated with a reduced risk of PCa with more than 7 cups/day. In addition, green tea catechins were effective for preventing PCa with an RR of 0.38 (P = 0.02). In conclusion, our dose-response meta-analysis evaluated the association of green tea intake with PCa risk systematically and quantitatively. And this is the first meta-analysis of green tea catechins consumption and PCa incidence. Our novel data demonstrated that higher green tea consumption was linearly reduced PCa risk with more than 7 cups/day and green tea catechins were effective for preventing PCa. However, further studies are required to substantiate these conclusions.

  6. Evaluation of the antioxidant properties of fruit and flavoured black teas.

    Science.gov (United States)

    Pękal, Anna; Dróżdż, Paulina; Biesaga, Magdalena; Pyrzynska, Krystyna

    2011-12-01

    Antioxidant properties of the water extracts of the commercial bagged fruit and flavoured black teas were evaluated and compared with typical black teas of C. sinensis. Folin-Ciocalteu (FC) assay, cupric ion reducing antioxidant capacity (CUPRAC) and DPPH radical method were used for these purposes. The content of selected flavonoids and phenolic acids was also determined by high-performance liquid chromatography with tandem mass spectrometry in the negative electrospray ionization mode. Flavoured black teas contain significantly higher level of catechins, quercetin, and rutin, while the content of chlorogenic and caffeic acids as well as naringin and hesperidin was higher in fruit teas. Supplementation with these flavonoids could reduce blood glucose. In FC and DPPH assays, the antioxidant properties of studied tea infusion increases in the order: fruit tea premium black tea, while in CUPRAC method, some aromatized teas exhibit the highest antioxidant properties. Tea infusions with nice smell of fruits would also support the human diet with some source of antioxidants.

  7. Quantification of Tea Flavonoids by High Performance Liquid Chromatography

    Science.gov (United States)

    Freeman, Jessica D.; Niemeyer, Emily D.

    2008-01-01

    We have developed a laboratory experiment that uses high performance liquid chromatography (HPLC) to quantify flavonoid levels in a variety of commercial teas. Specifically, this experiment analyzes a group of flavonoids known as catechins, plant-derived polyphenolic compounds commonly found in many foods and beverages, including green and black…

  8. Antioxidant capacity of different types of tea products | Karori ...

    African Journals Online (AJOL)

    In the present study, twelve different types of commercial tea samples were assayed to determine their phenolic composition and antioxidant activity. Reverse phase high performance liquid chromatography using a binary gradient system was used for the identification and quantification of individual catechins. Subsequently ...

  9. Green tea polyphenol induces significant cell death in human lung ...

    African Journals Online (AJOL)

    ... of EGCG on lung cancer cells, including H1155 cells, both in vitro and in vivo. The induction of reactive oxygen species, oxidative DNA damage, and apoptosis were evident following EGCG treatment. Keywords: Green tea, Lung cancer, Catechins, Epigallocatechin-3-gallate, Oxidative stress, Oxidative DNA damage ...

  10. Temporal patterns of caffeine intake in the United States.

    Science.gov (United States)

    Martyn, Danika; Lau, Annette; Richardson, Philip; Roberts, Ashley

    2018-01-01

    To investigate whether caffeine intake among adolescents and adults in the U.S. varies across the week or throughout the day, data from a 7-day online beverage consumption survey (2010-2011) were analyzed. Mean (206.8-213.0 mg/day) and 90th percentile (437.4-452.6 mg/day) daily caffeine intakes among consumers 13 years and older were relatively constant across the week with no marked difference among weekdays versus weekend days. Percent consumers of caffeinated beverages likewise remained stable across the week. Mean daily caffeine intake for coffee and energy drink consumers 13 years and older was higher than contributions for tea and carbonated soft drink consumers. Caffeinated beverage consumers (13 + yrs) consumed most of their caffeine in the morning (61% versus 21% and 18% in the afternoon and evening) which was driven by coffee. Caffeinated beverage consumption patterns among adolescents (13-17 yrs) - who typically consume less daily caffeine - were more evenly distributed throughout the day. These findings provide insight into U.S. temporal caffeine consumption patterns among specific caffeinated beverage consumers and different age brackets. These data suggest that while caffeine intakes do not vary from day-to-day, mornings generally drive the daily caffeine intake of adults and is predominantly attributed to coffee. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  11. Beverage caffeine intakes in the U.S.

    Science.gov (United States)

    Mitchell, Diane C; Knight, Carol A; Hockenberry, Jon; Teplansky, Robyn; Hartman, Terryl J

    2014-01-01

    Caffeine is one of the most researched food components, with the vast majority of dietary contributions coming from beverage consumption; however, there is little population-level data on caffeine intakes in the U.S. This study estimated the caffeine intakes of the U.S. population using a comprehensive beverage survey, the Kantar Worldpanel Beverage Consumption Panel. A nationally representative sample of 37,602 consumers (aged ≥ 2 years) of caffeinated beverages completed 7-day diaries which facilitated the development of a detailed database of caffeine values to assess intakes. Results showed that 85% of the U.S. population consumes at least one caffeinated beverage per day. The mean (±SE) daily caffeine intake from all beverages was 165±1 mg for all ages combined. Caffeine intake was highest in consumers aged 50-64 years (226±2 mg/day). The 90th percentile intake was 380 mg/day for all ages combined. Coffee was the primary contributor to caffeine intakes in all age groups. Carbonated soft drinks and tea provided a greater percentage of caffeine in the younger (caffeinated beverage consumption patterns and caffeine intakes in the U.S. population. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. The Safety of Ingested Caffeine: A Comprehensive Review

    Directory of Open Access Journals (Sweden)

    Jennifer L. Temple

    2017-05-01

    Full Text Available Caffeine is the most widely consumed psychoactive drug in the world. Natural sources of caffeine include coffee, tea, and chocolate. Synthetic caffeine is also added to products to promote arousal, alertness, energy, and elevated mood. Over the past decade, the introduction of new caffeine-containing food products, as well as changes in consumption patterns of the more traditional sources of caffeine, has increased scrutiny by health authorities and regulatory bodies about the overall consumption of caffeine and its potential cumulative effects on behavior and physiology. Of particular concern is the rate of caffeine intake among populations potentially vulnerable to the negative effects of caffeine consumption: pregnant and lactating women, children and adolescents, young adults, and people with underlying heart or other health conditions, such as mental illness. Here, we review the research into the safety and safe doses of ingested caffeine in healthy and in vulnerable populations. We report that, for healthy adults, caffeine consumption is relatively safe, but that for some vulnerable populations, caffeine consumption could be harmful, including impairments in cardiovascular function, sleep, and substance use. We also identified several gaps in the literature on which we based recommendations for the future of caffeine research.

  13. Effect of Green Tea Phytochemicals on Mood and Cognition.

    Science.gov (United States)

    Dietz, Christina; Dekker, Matthijs

    2017-01-01

    Green tea is traditionally known to induce mental clarity, cognitive function, physical activation and relaxation. Recently, a special green tea, matcha tea, is rapidly gaining popularity throughout the world and is frequently referred to as a mood- and brain food. Matcha tea consumption leads to much higher intake of green tea phytochemicals compared to regular green tea. Previous research on tea constituents caffeine, L-theanine, and epigallocatechin gallate (EGCG) repeatedly demonstrated benefits on mood and cognitive performance. These effects were observed when these phytochemicals were consumed separately and in combination. A review was conducted on 49 human intervention studies to summarize the research on acute psychoactive effects of caffeine, L-theanine, and EGCG on different dimensions of mood and cognitive performance. Caffeine was found to mainly improve performance on demanding long-duration cognitive tasks and self-reported alertness, arousal, and vigor. Significant effects already occurred at low doses of 40 mg. L-theanine alone improved self-reported relaxation, tension, and calmness starting at 200 mg. L-theanine and caffeine combined were found to particularly improve performance in attention-switching tasks and alertness, but to a lesser extent than caffeine alone. No conclusive evidence relating to effects induced by EGCG could be given since the amount of intervention studies was limited. These studies provided reliable evidence showing that L-theanine and caffeine have clear beneficial effects on sustained attention, memory, and suppression of distraction. Moreover, L-theanine was found to lead to relaxation by reducing caffeine induced arousal. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Synergistic effect of a catechin-immobilized poly(3,4-ethylenedioxythiophene)-modified electrode on electrocatalysis of NADH in the presence of ascorbic acid and uric acid

    International Nuclear Information System (INIS)

    Vasantha, V.S.; Chen, S.-M.

    2006-01-01

    Catechin is a polyphenolic flavonoid that can be isolated from a variety of natural sources, including tea leaves, grape seeds, and the wood and bark of trees such as acacia and mahogany. In our experiments, catechin was immobilized on PEDOT/GC (poly(3,4-ethylenedioxythiophene)/glassy carbon)-modified electrodes and used as a mediator for NADH (nicotinamide adenine dinucleotide) oxidation. The effect of the PEDOT thickness on the surface coverage of the catechin molecules was studied using cyclic voltammetry. The electrochemical properties and the effect of pH on the redox properties of the immobilized catechin molecules were studied by cyclic voltammetry in phosphate solution. The electrocatalytic oxidation of NADH at different electrode surfaces such as the bare GC-, the PEDOT/GC-, the catechin/GC- and the catechin/PEDOT/GC-modified electrodes was explored in phosphate solution at pH 7. In the catechin/PEDOT/GC-modified electrode, the PEDOT film plays an important role in resolving the oxidation potentials of ascorbic acid and NADH into two peaks that occur at the same potential for the catechin/GC-modified electrode surface. The heterogeneous electron transfer rate constant for NADH oxidation at the catechin/PEDOT/GC-modified electrode was determined using the rotating disk electrode technique and found to be 9.88 x 10 3 M -1 s -1 . The amperometric determination of NADH at the catechin/PEDOT/GC electrode was tested. The sensitivity of the electrode was 19 nA/μM

  15. Caffeine in Pregnancy

    Science.gov (United States)

    ... Home > Pregnancy > Nutrition, weight & fitness > Caffeine in pregnancy Caffeine in pregnancy E-mail to a friend Please ... two cups of coffee a day. What is caffeine? Caffeine is a drug found in things like ...

  16. Caffeine in the diet

    Science.gov (United States)

    Diet - caffeine ... Caffeine is absorbed and passes quickly into the brain. It does not collect in the bloodstream or ... been consumed. There is no nutritional need for caffeine. It can be avoided in the diet. Caffeine ...

  17. Catechins activate muscle stem cells by Myf5 induction and stimulate muscle regeneration.

    Science.gov (United States)

    Kim, A Rum; Kim, Kyung Min; Byun, Mi Ran; Hwang, Jun-Ha; Park, Jung Il; Oh, Ho Taek; Kim, Hyo Kyeong; Jeong, Mi Gyeong; Hwang, Eun Sook; Hong, Jeong-Ho

    2017-07-22

    Muscle weakness is one of the most common symptoms in aged individuals and increases risk of mortality. Thus, maintenance of muscle mass is important for inhibiting aging. In this study, we investigated the effect of catechins, polyphenol compounds in green tea, on muscle regeneration. We found that (-)-epicatechin gallate (ECG) and (-)-epigallocatechin-3-gallate (EGCG) activate satellite cells by induction of Myf5 transcription factors. For satellite cell activation, Akt kinase was significantly induced after ECG treatment and ECG-induced satellite cell activation was blocked in the presence of Akt inhibitor. ECG also promotes myogenic differentiation through the induction of myogenic markers, including Myogenin and Muscle creatine kinase (MCK), in satellite and C2C12 myoblast cells. Finally, EGCG administration to mice significantly increased muscle fiber size for regeneration. Taken together, the results suggest that catechins stimulate muscle stem cell activation and differentiation for muscle regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. The Relationship Between Caffeine, Sleep, and Behavior in Children.

    Science.gov (United States)

    Watson, Emily J; Banks, Siobhan; Coates, Alison M; Kohler, Mark J

    2017-04-15

    To examine caffeine consumption from various dietary sources in a cohort of Australian children and the relationship between caffeine consumption, sleep, and daytime behavior. Children aged 8 to 12 years and their parents/guardians completed a battery of questionnaires. Children completed a caffeine questionnaire while parents completed questionnaires regarding demographics, sleep, and behavior. The final sample consisted of 309 children (mean ± standard deviation [SD] age 10.6 ± 1.3 years, male = 48%) and corresponding parent reports. On average a mean ± SD 10.2 ± 17.4 mg/day of caffeine was consumed with a range of zero to 151 mg/day. Of the children who consumed caffeine (87% of the sample), the largest contributor was coffee and tea; making up 41% of total caffeine intake, and sodas (soft drinks) contributed to 40% of caffeine intake. Total caffeine consumption was significantly associated with sleep routine ( r = 0.152); morning tiredness ( r = 0.129); restless sleep ( r = 0.113); and internalizing behavioral problems ( r = 0.128). Using path analysis, caffeine consumption was positively associated with morning tiredness (β = 0.111, P = .050) which was positively associated with internalizing behaviors (β = 0.432, P sleep routine and restless sleep to the model led to a complete mediation of caffeine consumption on morning tiredness, as well as a partial mediation of the association between morning tiredness and internal behaviors. In 8- to 12-year-olds the primary sources of caffeine are coffee/tea and sodas. Overall mean caffeine consumption is small by adult standards but has an effect on behavior and sleep in children. The effect on behavior is mediated by disrupted sleep, indicating that caffeine is a contributor to sleep problems and related behavior in children. © 2017 American Academy of Sleep Medicine

  19. Green tea and the risk of prostate cancer

    Science.gov (United States)

    Guo, Yuming; Zhi, Fan; Chen, Ping; Zhao, Keke; Xiang, Han; Mao, Qi; Wang, Xinghuan; Zhang, Xinhua

    2017-01-01

    Abstract Prostate cancer (PCa) now remains the 2nd most frequently diagnosed cancer. In recent years, chemoprevention for PCa becomes a possible concept. Especially, many phytochemicals rich foods are suggested to lower the risk of cancer. Among these foods, green tea is considered as effective prevention for various cancers. However, clinical trials and previous meta-analyses on the relationship between green tea consumption and the risk of PCa have produced inconsistent outcomes. This study aims to determine the dose–response association of green tea intake with PCa risk and the preventive effect of green tea catechins on PCa risk. Seven observational studies and 3 randomized controlled trials were retrieved from Cochrane Library, PubMed, Sciencedirect Online, and hand searching. The STATA (version 12.0) was applied to analyze the data. The relative risks (RRs) and 95% confidence intervals were pooled by fixed or random effect modeling. Dose–response relations were evaluated with categories of green tea intake. Although there was no statistical significance in the comparison of the highest versus lowest category, there was a trend of reduced incidence of PCa with each 1 cup/day increase of green tea (P = 0.08). Our dose–response meta-analysis further demonstrated that higher green tea consumption was linearly associated with a reduced risk of PCa with more than 7 cups/day. In addition, green tea catechins were effective for preventing PCa with an RR of 0.38 (P = 0.02). In conclusion, our dose–response meta-analysis evaluated the association of green tea intake with PCa risk systematically and quantitatively. And this is the first meta-analysis of green tea catechins consumption and PCa incidence. Our novel data demonstrated that higher green tea consumption was linearly reduced PCa risk with more than 7 cups/day and green tea catechins were effective for preventing PCa. However, further studies are required to substantiate these conclusions

  20. Caffeine adsorption of montmorillonite in coffee extracts.

    Science.gov (United States)

    Shiono, Takashi; Yamamoto, Kenichiro; Yotsumoto, Yuko; Yoshida, Aruto

    2017-08-01

    The growth in health-conscious consumers continues to drive the demand for a wide variety of decaffeinated beverages. We previously developed a new technology using montmorillonite (MMT) in selective decaffeination of tea extract. This study evaluated and compared decaffeination of coffee extract using MMT and activated carbon (AC). MMT adsorbed caffeine without significant adsorption of caffeoylquinic acids (CQAs), feruloylquinic acids (FQAs), dicaffeoylquinic acids (di-CQAs), or caffeoylquinic lactones (CQLs). AC adsorbed caffeine, chlorogenic acids (CGAs) and CQLs simultaneously. The results suggested that the adsorption selectivity for caffeine in coffee extract is higher in MMT than AC. The caffeine adsorption isotherms of MMT in coffee extract fitted well to the Langmuir adsorption model. The adsorption properties in coffee extracts from the same species were comparable, regardless of roasting level and locality of growth. Our findings suggest that MMT is a useful adsorbent in the decaffeination of a wide range of coffee extracts.

  1. Caffeine intake reduces sleep duration in adolescents.

    Science.gov (United States)

    Lodato, Francesca; Araújo, Joana; Barros, Henrique; Lopes, Carla; Agodi, Antonella; Barchitta, Martina; Ramos, Elisabete

    2013-09-01

    In our study, we hypothesized that higher caffeine intake would be associated with lower sleep duration among 13-year-old adolescents. In addition, we aimed to identify food sources of caffeine intake in this sample. Eligible participants were adolescents who were born in 1990 and attended school in Porto, Portugal, in 2003/2004. Self-administered questionnaires were used, and diet was evaluated using a food frequency questionnaire. From the 2160 eligible participants, only 1522 with valid information regarding their diet were included in this study. In our sample, the median intake of caffeine was 23.1 mg/d, with soft drinks being the major source. Ice tea presented the highest median (25th-75th percentiles) contribution (33.1% [14.0-52.1]), followed by cola (21.1% [6.4-37.6]). Regarding cocoa products, chocolate bars presented a median contribution of 5.1% (1.0-14.0), and snacks containing chocolate had a contribution of 3.0% (0.5-7.2). Coffee and tea presented a negligible contribution. Adolescents who reported less sleep duration and those who spent more time watching TV during the weekend had a significantly higher caffeine intake. Overall, boys had higher intakes of caffeine from soft drinks, and private school attendees, those who had parents with more education, who reported less television viewing time and had lower body mass index presented higher intakes of caffeine from chocolate. Considering sleeping more than 9.5 hours as a reference class, for each increase of 10 mg/d in caffeine intake, we found that the odds ratio of sleeping 8.5 hours or less was 1.12 (95% confidence interval, 1.06-1.19). Our results support the hypothesis that caffeine intake was inversely associated with sleep duration in adolescents. © 2013.

  2. Anti-inflammatory Action of Green Tea.

    Science.gov (United States)

    Ohishi, Tomokazu; Goto, Shingo; Monira, Pervin; Isemura, Mamoru; Nakamura, Yoriyuki

    2016-01-01

    Green tea has been shown to have beneficial effects against a variety of diseases such as cancer, obesity, diabetes, cardiovascular disease, and neurodegenerative diseases. Through cellular, animal, and human experiments, green tea and its major component, epigallocatechin-3-gallate (EGCG) have been demonstrated to have anti-inflammatory effects. Our previous findings have indicated that green tea and EGCG suppress the gene and/or protein expression of inflammatory cytokines and inflammation-related enzymes. Using bibliographic databases, particularly PubMed (provided by the http://www.ncbi.nlm.nih.gov/pubmed, US National Library of Medicine, National Institutes of Health, United States), we examined the potential usefulness of green tea/EGCG for the prevention and treatment of inflammatory diseases in human clinical and epidemiological studies. We also reviewed results from cellular and animal experiments and proposed action mechanisms. Most of the results from the human studies indicated the beneficial effects of green tea and tea catechins against inflammatory diseases. The cellular and animal studies also provided evidence for the favorable effects of green tea/EGCG. These results are compatible with our previous findings and can be largely explained by a mechanism wherein green tea/EGCG acts as an antioxidant to scavenge reactive oxygen species, leading to attenuation of nuclear factor-κB activity. Since green tea and EGCG have multiple targets and act in a pleiotropic manner, we may consider their usage to improve the quality of life in patients with inflammatory disease. Green tea and EGCG have beneficial health effects and no severe adverse effects; however, care should be taken to avoid overdosage, which may induce deleterious effects including hepatic injury. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  3. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    OpenAIRE

    Adam Drewnowski; Colin D. Rehm

    2016-01-01

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011?2012 data (n = 7456). Second, fourteen years trends in caffe...

  4. Caffeine and theanine exert opposite effects on attention under emotional arousal.

    Science.gov (United States)

    Giles, Grace E; Mahoney, Caroline R; Brunyé, Tad T; Taylor, Holly A; Kanarek, Robin B

    2017-01-01

    Tea is perceived as more relaxing than coffee, even though both contain caffeine. L-theanine in tea may account for the difference. Consumed together, caffeine and theanine exert similar cognitive effects to that of caffeine alone, but exert opposite effects on arousal, in that caffeine accentuates and theanine mitigates physiological and felt stress responses. We evaluated whether caffeine and theanine influenced cognition under emotional arousal. Using a double-blind, repeated-measures design, 36 participants received 4 treatments (200 mg caffeine + 0 mg theanine, 0 mg caffeine + 200 mg theanine, 200 mg caffeine + 200 mg theanine, 0 mg caffeine + 0 mg theanine) on separate days. Emotional arousal was induced by highly arousing negative film clips and pictures. Mood, salivary cortisol, and visual attention were evaluated. Caffeine accentuated global processing of visual attention on the hierarchical shape task (p Caffeine reduced flanker conflict difference scores on the Attention Network Test (p caffeine and theanine exert opposite effects on certain attentional processes, but when consumed together, they counteract the effects of each other.

  5. Nε-(carboxymethyl)lysine and Nε-(carboxyethyl)lysine in tea and the factors affecting their formation.

    Science.gov (United States)

    Jiao, Ye; He, Jialiang; Li, Fengli; Tao, Guanjun; Zhang, Shuang; Zhang, Shikang; Qin, Fang; Zeng, Maomao; Chen, Jie

    2017-10-01

    The levels of N ε -(carboxymethyl)lysine (CML) and N ε -(carboxyethyl)lysine (CEL) in 99 tea samples from 14 geographic regions, including 44 green, 7 oolong, 41 black, and 7 dark teas were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The CML and CEL contents varied from 11.0 to 1701μg/g tea and 4.6 to 133μg/g tea, respectively. Dark tea presented the highest levels of CML and CEL, whereas green and oolong teas presented the lowest levels. Five kinds of catechins in the tea were also analyzed, and spearman's correlation coefficients showed that all the catechins negatively correlated with CML and CEL. The results suggested that withering, fermentation and pile fermentation may facilitate the formation of CML and CEL. Catechins might inhibit the formation of CML and CEL, but their inhibitory effects may be affected by tea processing. The results of this study are useful for the production of healthier tea. Copyright © 2017. Published by Elsevier Ltd.

  6. A Presurgical Study of Lecithin Formulation of Green Tea Extract in Women with Early Breast Cancer.

    Science.gov (United States)

    Lazzeroni, Matteo; Guerrieri-Gonzaga, Aliana; Gandini, Sara; Johansson, Harriet; Serrano, Davide; Cazzaniga, Massimiliano; Aristarco, Valentina; Macis, Debora; Mora, Serena; Caldarella, Pietro; Pagani, Gianmatteo; Pruneri, Giancarlo; Riva, Antonella; Petrangolini, Giovanna; Morazzoni, Paolo; DeCensi, Andrea; Bonanni, Bernardo

    2017-06-01

    Epidemiologic data support an inverse association between green tea intake and breast cancer risk. Greenselect Phytosome (GSP) is a lecithin formulation of a caffeine-free green tea catechin extract. The purpose of the study was to determine the tissue distribution of epigallocatechin-3-O-gallate (EGCG) and its effect on cell proliferation and circulating biomarkers in breast cancer patients. Twelve early breast cancer patients received GSP 300 mg, equivalent to 44.9 mg of EGCG, daily for 4 weeks prior to surgery. The EGCG levels were measured before (free) and after (total) enzymatic hydrolysis by HPLC-MS/MS in plasma, urine, breast cancer tissue, and surrounding normal breast tissue. Fasting blood samples were taken at baseline, before the last administration, and 2 hours later. Repeated administration of GSP achieved levels of total EGCG ranging from 17 to 121 ng/mL in plasma. Despite a high between-subject variability, total EGCG was detectable in all tumor tissue samples collected up to 8 ng/g. Median total EGCG concentration was higher in the tumor as compared with the adjacent normal tissue (3.18 ng/g vs. 0 ng/g, P = 0.02). Free EGCG concentrations ranged from 8 to 65.8 ng/mL in plasma ( P between last administration and 2 hours after breast tumor tissue and is associated with antiproliferative effects on breast cancer tissue. Cancer Prev Res; 10(6); 363-9. ©2017 AACR . ©2017 American Association for Cancer Research.

  7. Can We Predict Cognitive Performance Decrements Due to Sleep Loss and the Recuperative Effects of Caffeine

    Science.gov (United States)

    2015-10-14

    approximation for caffeine when ingested via coffee, tea, energy drinks , and most gum products, where the absorption rate is much faster (by a factor......such as timely short naps and caffeine , are often used to mitigate the effects of sleep loss on performance. However, the timing, duration, and dosage

  8. Methylxanthine and catechin content of fresh and fermented cocoa beans, dried cocoa beans, and cocoa liquor

    Directory of Open Access Journals (Sweden)

    Pedro P. Peláez

    2016-01-01

    Full Text Available The theobromine and catechin content can affect the quality of cocoa liquor and is influenced by cacao variety, production area (PA, and fermentation, as well as the method of drying beans (FDB and cocoa liquor production (CLP. This study examined variationsin methylxanthine and catechin levels in fresh and fermented cocoa beans, dried cocoa grains, and in cocoa liquor from Trinitario, Criollo, and Forastero cacao varieties. A total of 123 cocoa bean samples from three Peruvian PAs at different altitudes, Tingo María (TM, San Alejandro (SA, and Curimana (CU, were evaluated. The theobromine (Tb and caffeine (Cf contents in fresh cocoa beans were affected by both cocoa type and PA. The caffeine content was higher in Trinitario cacao than in Criollo and Forastero varieties (p ≤ 0.05. The Tb and CF contents decreased in dry cocoa grain and was affected by FDB (p ≤ 0.05 (1.449 ± 0.004 to 1.140 ± 0.010 and 0.410 ± 0.03 to 0.165 ± 0.02 g Tb and C, respectively, per 100 g dry weight. Cocoa beans from Tingo María, which has thehighest altitude, had higher Tb and CF contents than those from other PAs. The catechin (C and epicatechin (EC contents were affected by the FDB and CLP, and were highestin fresh cocoa beans from the Tingo María area (range: 0.065 ± 0.01 to 0.020 ± 0.00 g C/100 g. The C and EC contents decreased during FDB and CLP (0.001 g C/100 g of cocoa liquor. Taken together, these results show that higher concentrations of Tb, Cf, C,and EC are present in fresh cocoa beans. Moreover, the cocoa variety influenced cocoa liquor quality. Overall, cocoa from the Tingo María PA had the most desirable chemical composition.

  9. Physicochemical Characterization of Inclusion Complex of Catechin ...

    African Journals Online (AJOL)

    Its physicochemical properties were investigated by ultravioletvisible spectrometry (UV), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffractometry (XRD) and differential scanning calorimetry (DSC). Results: The characteristic UV absorption peaks for catechin, the physical ...

  10. Differences in quality parameters between types of commercial tea from Argentina

    Directory of Open Access Journals (Sweden)

    Ana Eugenia Thea

    2012-10-01

    Full Text Available Normal 0 21 false false false ES X-NONE X-NONE To determine differences in quality parameters between different types of tea elaborated in Argentina, water extract, crude fibre, caffeine, total polyphenol content, antioxidant activity, sorption isotherms and colour parameters (L, a, b were determined. Fifty-one industrial samples of commercially available teas including green tea, semifermented tea, black tea and black tea sub-product (BTSP were used for this study.Water extract contents were significantly higher in black tea and green tea (40.3% and 40.7% w/w, respectively, while semifermented tea and BTSP showed higher levels of crude fibre (22.3% and 20.4% w/w, respectively. Caffeine contents of black teas (2.7% w/w were significantly higher than in the other types of tea. Green teas revealed the highest concentrations of phenolic compounds and the major antioxidant activities (14.9 g GAE/100g dm and 30.0 g AAE/100g dm, respectively. The results also highlighted significant differences (p<0.05 in colour values between the different types of tea.

  11. An Update on the Health Benefits of Green Tea

    Directory of Open Access Journals (Sweden)

    Wanda C. Reygaert

    2017-01-01

    Full Text Available Green tea, which is produced from the leaves of the Camellia sinensis plant, is one of the most popular beverages worldwide. Over the past 30 years or more, scientists have studied this plant in respect to potential health benefits. Research has shown that the main components of green tea that are associated with health benefits are the catechins. The four main catechins found in green tea are: (−-epicatechin (EC, (−-epicatechin-3-gallate (ECG, (−-epigallocatechin (EGC, and (−-epigallocatechin-3-gallate (EGCG. Of these four, EGCG is present in the largest quantity, and so has been used in much of the research. Among the health benefits of green tea are: anticarcinogenic, anti-inflammatory, antimicrobial, and antioxidant properties, and benefits in cardiovascular disease and oral health. Research has been carried out using various animal models and cells lines, and is now more and more being carried out in humans. This type of research will help us to better understand the direct benefits of green tea. This review will focus primarily on research conducted using human subjects to investigate the health benefits of green tea.

  12. Caffeine in your drink: natural or synthetic?

    Science.gov (United States)

    Zhang, Lijun; Kujawinski, Dorothea M; Federherr, Eugen; Schmidt, Torsten C; Jochmann, Maik A

    2012-03-20

    Owing to possible adulteration and health concerns, it is important to discriminate between natural and synthetic food ingredients. A new method for compound-specific isotope analysis (CSIA) by coupling high-temperature reversed-phase liquid chromatography to isotope ratio mass spectrometry (HT-RPLC/IRMS) was developed for discrimination of natural and synthetic caffeine contained in all types of drinks. The analytical parameters such as stationary phase, column inner diameter, and column temperature were optimized for the separation of caffeine directly from drinks (without extraction). On the basis of the carbon isotope analysis of 42 natural caffeine samples including coffee beans, tea leaves, guaraná powder, and maté leaves, and 20 synthetic caffeine samples from different sources by high-temperature reversed-phase liquid chromatography coupled to isotope ratio mass spectrometry, it is concluded that there are two distinguishable groups of caffeine δ(13)C-values: one between -25 and -32‰ for natural caffeine, and the other between -33 and -38‰ for synthetic caffeine. Isotope analysis by HT-RPLC/IRMS has been applied to identify the caffeine source in 38 drinks. Four mislabeled products were detected due to added but nonlabeled synthetic caffeine with δ(13)C-values lower than -33‰. This work is the first application of HT-RPLC/IRMS to real-world food samples, which showed several advantages: simple sample preparation (only dilution), high throughput, long-term column stability, and high precision of δ(13)C-value. Thus, HT-RPLC/IRMS can be a very promising tool in stable isotope analysis of nonvolatile compounds.

  13. Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children

    OpenAIRE

    Richards, Gareth; Smith, Andrew

    2015-01-01

    Previous research suggests that effects of caffeine on behaviour are positive unless one is investigating sensitive groups or ingestion of large amounts. Children are a potentially sensitive subgroup, and especially so considering the high levels of caffeine currently found in energy drinks. The present study used data from the Cornish Academies Project to investigate associations between caffeine (both its total consumption, and that derived separately from energy drinks, cola, tea, and coff...

  14. Assessing dietary exposure to caffeine from beverages in the U.S. population using brand-specific versus category-specific caffeine values.

    Science.gov (United States)

    Mitchell, Diane C; Hockenberry, Jon; Teplansky, Robyn; Hartman, Terryl J

    2015-06-01

    Recent reports on caffeine intakes in the United States have highlighted the importance of obtaining accurate and valid measures of caffeine exposure. The objective of this study is to compare two methods of assigning caffeine values to beverages: brand-specific values versus an aggregate single value representing a broader range of products within a beverage category (i.e., category-specific). The two methods yielded some small, but statistically significant differences in the estimation of caffeine intake from coffee, tea, and carbonated soft drinks (CSDs) for all ages combined and within several of the adult age groups (i.e., 35-49, 50-64, and ≥65 years). These differences, while small, suggest that detailed brand-specific data, particularly for CSDs, commercially pre-packaged or bottled teas, coffee, and specialty coffee drinks, provide more accurate estimates of caffeine exposure for some age groups. Despite these differences, these data provide some assurance that studies using a single aggregate caffeine value provide reasonable measures of caffeine exposure, particularly for studies conducted over a decade ago when there were fewer caffeinated products and brand-specific data available. As the caffeinated beverage marketplace continues to evolve, the use of more detailed, brand-specific data will likely strengthen the assessment of caffeine exposure in the United States. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Black Tea

    Science.gov (United States)

    ... leaves of the same plant, has some different properties. Black tea is used for improving mental alertness ... that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen ( ...

  16. Caffeine and Migraine

    Science.gov (United States)

    ... Spotlight On News Content Capsule Contact Understanding Migraine Caffeine and Migraine Doctor Q&A Managing Migraine Migraine ... of Headache Disorders Cluster Headache Post-Traumatic Headache Caffeine and Migraine January 10, 2017 Key Points Caffeine ...

  17. Remediation of azo dyes by using household used black tea as an ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... to remove pollutants such as colors, dyes and metal impurities (Khan, 2002). Some of the adsorbent ... and color characteristics of tea include polyphenolic bo- dies, caffeine, non-caffeine nitrogenous ..... for the removal of chromium (VI) from aqueous solutions on the activated carbons prepared from ...

  18. Caffeine levels in beverages from Argentina's market: application to caffeine dietary intake assessment.

    Science.gov (United States)

    Olmos, V; Bardoni, N; Ridolfi, A S; Villaamil Lepori, E C

    2009-03-01

    The caffeine content of different beverages from Argentina's market was measured. Several brands of coffees, teas, mates, chocolate milks, soft and energy drinks were analysed by high-performance liquid chromatography (HPLC) with ultraviolet detection. The highest concentration level was found in short coffee (1.38 mg ml(-1)) and the highest amount per serving was found in instant coffee (95 mg per serving). A consumption study was also carried out among 471 people from 2 to 93 years of age to evaluate caffeine total dietary intake by age and to identify the sources of caffeine intake. The mean caffeine intake among adults was 288 mg day(-1) and mate was the main contributor to that intake. The mean caffeine intake among children of 10 years of age and under was 35 mg day(-1) and soft drinks were the major contributors to that intake. Children between 11 and 15 years old and teenagers (between 16 and 20 years) had caffeine mean intakes of 120 and 240 mg day(-1), respectively, and mate was the major contributor to those intakes. Drinking mate is a deep-rooted habit among Argentine people and it might be the reason for their elevated caffeine mean daily intake.

  19. Determination of the caffeine contents of various food items within the Austrian market and validation of a caffeine assessment tool (CAT).

    Science.gov (United States)

    Rudolph, E; Färbinger, A; König, J

    2012-01-01

    The caffeine content of 124 products, including coffee, coffee-based beverages, energy drinks, tea, colas, yoghurt and chocolate, were determined using RP-HPLC with UV detection after solid-phase extraction. Highest concentrations of caffeine were found for coffee prepared from pads (755 mg l⁻¹) and regular filtered coffee (659 mg l⁻¹). The total caffeine content of coffee and chocolate-based beverages was between 15 mg l⁻¹ in chocolate milk and 448 mg l⁻¹ in canned ice coffee. For energy drinks the caffeine content varied in a range from 266 to 340 mg l⁻¹. Caffeine concentrations in tea and ice teas were between 13 and 183 mg l⁻¹. Coffee-flavoured yoghurts ranged from 33 to 48 mg kg⁻¹. The caffeine concentration in chocolate and chocolate bars was between 17 mg kg⁻¹ in whole milk chocolate and 551 mg kg⁻¹ in a chocolate with coffee filling. A caffeine assessment tool was developed and validated by a 3-day dietary record (r²= 0.817, p caffeine saliva concentrations (r²= 0.427, p < 0.01).

  20. Effect of Tea Polyphenol Compounds on Anticancer Drugs in Terms of Anti-Tumor Activity, Toxicology, and Pharmacokinetics.

    Science.gov (United States)

    Cao, Jianhua; Han, Jie; Xiao, Hao; Qiao, Jinping; Han, Mei

    2016-12-14

    Multidrug resistance and various adverse side effects have long been major problems in cancer chemotherapy. Recently, chemotherapy has gradually transitioned from mono-substance therapy to multidrug therapy. As a result, the drug cocktail strategy has gained more recognition and wider use. It is believed that properly-formulated drug combinations have greater therapeutic efficacy than single drugs. Tea is a popular beverage consumed by cancer patients and the general public for its perceived health benefits. The major bioactive molecules in green tea are catechins, a class of flavanols. The combination of green tea extract or green tea catechins and anticancer compounds has been paid more attention in cancer treatment. Previous studies demonstrated that the combination of chemotherapeutic drugs and green tea extract or tea polyphenols could synergistically enhance treatment efficacy and reduce the adverse side effects of anticancer drugs in cancer patients. In this review, we summarize the experimental evidence regarding the effects of green tea-derived polyphenols in conjunction with chemotherapeutic drugs on anti-tumor activity, toxicology, and pharmacokinetics. We believe that the combination of multidrug cancer treatment with green tea catechins may improve treatment efficacy and diminish negative side effects.

  1. Effect of Tea Polyphenol Compounds on Anticancer Drugs in Terms of Anti-Tumor Activity, Toxicology, and Pharmacokinetics

    Directory of Open Access Journals (Sweden)

    Jianhua Cao

    2016-12-01

    Full Text Available Multidrug resistance and various adverse side effects have long been major problems in cancer chemotherapy. Recently, chemotherapy has gradually transitioned from mono-substance therapy to multidrug therapy. As a result, the drug cocktail strategy has gained more recognition and wider use. It is believed that properly-formulated drug combinations have greater therapeutic efficacy than single drugs. Tea is a popular beverage consumed by cancer patients and the general public for its perceived health benefits. The major bioactive molecules in green tea are catechins, a class of flavanols. The combination of green tea extract or green tea catechins and anticancer compounds has been paid more attention in cancer treatment. Previous studies demonstrated that the combination of chemotherapeutic drugs and green tea extract or tea polyphenols could synergistically enhance treatment efficacy and reduce the adverse side effects of anticancer drugs in cancer patients. In this review, we summarize the experimental evidence regarding the effects of green tea-derived polyphenols in conjunction with chemotherapeutic drugs on anti-tumor activity, toxicology, and pharmacokinetics. We believe that the combination of multidrug cancer treatment with green tea catechins may improve treatment efficacy and diminish negative side effects.

  2. Caffeine consumption among active duty United States Air Force personnel.

    Science.gov (United States)

    Knapik, Joseph J; Austin, Krista G; McGraw, Susan M; Leahy, Guy D; Lieberman, Harris R

    2017-07-01

    Data from the National Health and Nutrition Examination Survey (NHANES) indicated that 89% of Americans regularly consumed caffeinated products, but these data did not include military personnel. This cross-sectional study examined caffeine consumption prevalence, amount of daily consumption, and factors associated with caffeine intake in active duty United States (US) Air Force personnel. Service members (N = 1787) stationed in the US and overseas completed a detailed questionnaire describing their intake of caffeine-containing products in addition to their demographic, lifestyle, and military characteristics. Overall, 84% reported consuming caffeinated products ≥1 time/week with caffeine consumers ingesting a mean ± standard error of 212 ± 9 mg/day (224 ± 11 mg/day for men, 180 ± 12 mg/day for women). The most commonly consumed caffeinated products (% users) were sodas (56%), coffee (45%), teas (36%), and energy drinks (27%). Multivariate logistic regression modeling indicated that characteristics independently associated with caffeine consumption (≥1 time/week) included older age, ethnicity other than black, tobacco use, less aerobic training, and less sleep; energy drink use was associated with male gender, younger age, tobacco use, and less sleep. Compared to NHANES data, the prevalence of caffeine consumption in Air Force personnel was similar but daily consumption (mg/day) was higher. Published by Elsevier Ltd.

  3. Polymeric nanoparticles encapsulating white tea extract for nutraceutical application.

    Science.gov (United States)

    Sanna, Vanna; Lubinu, Giuseppe; Madau, Pierluigi; Pala, Nicolino; Nurra, Salvatore; Mariani, Alberto; Sechi, Mario

    2015-02-25

    With the aim to obtain controlled release and to preserve the antioxidant activity of the polyphenols, nanoencapsulation of white tea extract into polymeric nanoparticles (NPs) based on poly(ε-caprolactone) (PCL) and alginate was successfully performed. NPs were prepared by nanoprecipitation method and were characterized in terms of morphology and chemical properties. Total polyphenols and catechins contents before and after encapsulation were determined. Moreover, in vitro release profiles of encapsulated polyphenols from NPs were investigated in simulated gastrointestinal fluids. The antioxidant activity and stability of encapsulated extract were further evaluated. Interestingly, NPs released 20% of the polyphenols in simulated gastric medium, and 80% after 5 h at pH 7.4, showing a good capacity to control the polyphenols delivery. Furthermore, DPPH(•) assay confirmed that white tea extract retained its antioxidant activity and NPs protected tea polyphenols from degradation, thus opening new perspectives for the exploitation of white tea extract-loaded NPs for nutraceutical applications.

  4. Trends in intake and sources of caffeine in the diets of US adults: 2001-2010.

    Science.gov (United States)

    Fulgoni, Victor L; Keast, Debra R; Lieberman, Harris R

    2015-05-01

    Coffee and tea are traditional sources of caffeine in the diet, but other sources, such as energy drinks, are now available. Because risks and benefits of caffeine use are dose dependent, the public health consequences of caffeine consumption cannot be determined without data on amounts currently consumed by the US population. The objective was to obtain an up-to-date, nationally representative estimate of caffeine consumption in adults. Dietary intake data from NHANES from 2001 to 2010 for adults ≥19 y of age were used (n = 24,808). Acute and usual intake of caffeine was estimated from all caffeine-containing foods and beverages. Trends in consumption and changes in sources of caffeine were also examined. Eighty-nine percent of the adult US population consumed caffeine, with equal prevalence in men and women. Usual mean ± SE per capita caffeine consumption when nonusers were included was 186 ± 4 mg/d, with men consuming more than women (211 ± 5 vs. 161 ± 3 mg/d, P coffee (∼64%), tea (∼16%), and soft drinks (∼18%) predominant sources; energy drinks provided <1%, but their consumption increased substantially from 2001 to 2010. Although new caffeine-containing products were introduced into the US food supply, total per capita intake was stable over the period examined. © 2015 American Society for Nutrition.

  5. Green tea in dermatology--myths and facts.

    Science.gov (United States)

    Zink, Alexander; Traidl-Hoffmann, Claudia

    2015-08-01

    Green tea consumption has a long tradition in Asian countries--especially China. The epidemiologically and experimentally observed anticarcinogenic and antiinflammatory effects of green tea have led to the implementation of green tea extracts in multiple therapeutic applications - both in dermatological and cosmeceutical preparations. The most abundant evidence exists for the anticarcinogenic and chemopreventive effect of green tea or its major constituent epigallocatechin-3-gallate. Almost equally evident is the effect in infectious diseases such as cutaneous viral infections. For external genital warts, a topical ointment with green tea extracts was licensed in the USA in 2010, and recently also in Europe. Experimental evidence pinpointing the block of central signal transduction factors in inflammatory mechanisms has led to the evaluation of catechins in inflammatory disorders such as atopic dermatitis. The belief of green tea as a "wonder weapon" against diseases dates back thousands of years. According to a Chinese legend, ancient Emperor Shen Nung noted a delightful aroma after some leaves of a nearby tree had fallen into boiling water. He immediately proclaimed the new "drink" as "heaven-sent", starting the belief - persisting until today - of green tea as a medication from nature against many different diseases. This review summarizes biological effects and clinical implications of green tea. © 2015 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  6. [Caffeine--common ingredient in a diet and its influence on human health].

    Science.gov (United States)

    Wierzejska, Regina

    2012-01-01

    consumption by Polish population is concerned there is very few data in this subject so far. In the nineties of the previous century it was 141 mg per day, whereas according to recent survey daily caffeine intake by women from the Warsaw region was 251 mg and 15% of examined women consumed an excessive quantity of caffeine (> or = 400 mg). Smokers consume more caffeine than nonsmokers, similarly to persons with mental illnesses. With reference to the caffeine consumption it should be underline that caffeine content in coffee and tea beverages varies greatly depending on the method of brewing whereas the content of caffeine in many brands of energy drinks can much vary. This should be taken into account in the daily caffeine intake.

  7. Microwave-assisted water extraction of green tea polyphenols.

    Science.gov (United States)

    Nkhili, Ezzohra; Tomao, Valerie; El Hajji, Hakima; El Boustani, Es-Seddik; Chemat, Farid; Dangles, Olivier

    2009-01-01

    Green tea, a popular drink with beneficial health properties, is a rich source of specific flavanols (polyphenols). There is a special interest in the water extraction of green tea polyphenols since the composition of the corresponding extracts is expected to reflect the one of green tea infusions consumed worldwide. To develop a microwave-assisted water extraction (MWE) of green tea polyphenols. MWE of green tea polyphenols has been investigated as an alternative to water extraction under conventional heating (CWE). The experimental conditions were selected after consideration of both temperature and extraction time. The efficiency and selectivity of the process were determined in terms of extraction time, total phenolic content, chemical composition (HPLC-MS analysis) and antioxidant activity of the extracts. By MWE (80 degrees C, 30 min), the flavanol content of the extract reached 97.46 (+/- 0.08) mg of catechin equivalent/g of green tea extract, vs. only 83.06 (+/- 0.08) by CWE (80 degrees C, 45 min). In particular, the concentration of the most bioactive flavanol EGCG was 77.14 (+/- 0.26) mg of catechin equivalent/g of green tea extract obtained by MWE, vs 64.18 (+/- 0.26) mg/g by CWE. MWE appears more efficient than CWE at both 80 and 100 degrees C, particularly for the extraction of flavanols and hydroxycinnamic acids. Although MWE at 100 degrees C typically affords higher yields in total phenols, MWE at 80 degrees C appears more convenient for the extraction of the green tea-specific and chemically sensitive flavanols.

  8. Caffeine and Your Child

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Caffeine KidsHealth / For Parents / Caffeine What's in this article? ... español La cafeína y su hijo What Is Caffeine? Caffeine is a natural stimulant found in coffee, ...

  9. Production of γ-Amino Butyric Acid in Tea Leaves wit Treatment of Lactic Acid Bacteria

    Science.gov (United States)

    Watanabe, Yuko; Hayakawa, Kiyoshi; Ueno, Hiroshi

    Lactic acid bacteria was searched for producing termented tea that contained a lot of γ-amino butyric acid(GABA). Also examined were the growth condition, GABA production and changes in catechin contents in the tea leaves. Lactobacillus brevis L12 was found to be suitable for the production of fermented tea since it gave as much GABA as gabaron tea when tea leaves being suspended with water at 10% and incubated for 4 days at 25°C. The amount of GABA produced was more than calculated based upon the content of glutamic acid in tea leaves. It is probable to assume that glutamate derived from glutamine and theanine is converted into GABA.

  10. Caffeine Awareness in Children: Insights from a Pilot Study.

    Science.gov (United States)

    Thakre, Tushar P; Deoras, Ketan; Griffin, Catherine; Vemana, Aarthi; Podmore, Petra; Krishna, Jyoti

    2015-07-15

    Caffeine, a commonly consumed psychoactive substance, can have significant effects on sleep. Caffeine intake among children is increasing, mainly in the form of sodas. However, adolescent caffeine consumers may lack knowledge about the caffeine content in common beverages. If true, this very fact may hamper the assessment of the effects of caffeine consumption on sleep in children if such assessments are a priori dependent on responders being able to reliably distinguish between caffeinated and noncaffeinated beverages. This preliminary study investigated adolescents' caffeine knowledge and intake at a Cleveland-area public middle school. Seventh- and eighth-grade students were surveyed using: (1) the Caffeine Literacy and Sleep Study (CLASS), a 15-question pilot instrument designed to assess caffeine knowledge and intake by type, quantity and timing, as well as sleep habits; and (2) the Cleveland Adolescent Sleepiness Questionnaire (CASQ), a validated survey measuring excessive daytime sleepiness in adolescents. These questionnaires were distributed and collected during a specified class period. Of the 635 seventh- and eighth-grade students who attended school on the day of the study, 555 (87%) participated. Lack of knowledge about caffeine content of particular drinks was noted in seventh and eighth graders of both sexes with nearly 29% unaware that their favorite drinks contain caffeine and more than 50% unable to correctly identify the drinks with the most caffeine. A low percentage of students correctly identified light-colored sodas lacking caffeine: 7-Up (24.1%), Sierra Mist (38.9%), ginger ale (39.8%), Sprite (39.8%), and Fresca (53.7%). The percentages of students correctly identifying caffeinated light-colored beverages were: Arizona Green Tea (43.5%), Mello Yellow (50.9%), and A&W cream soda (67.6%). However, Mountain Dew was correctly identified by most (93.5%) as caffeinated. Students were not consistently able to identify caffeine content or lack

  11. Evaluation of authenticity and green tea antimicrobial activity of different commercial brands that are sold in San Jose, Costa Rica

    International Nuclear Information System (INIS)

    Alvarez Campos, Jeyson

    2014-01-01

    Various brands of green tea are compared with the leaves of camellia sinensis to verify the antimicrobial effect, authenticity and quality. The main components with antibacterial effect commercially presented are compared to the components present in green tea leaf to determine the quality and authenticity, by thin layer chromatography. The brands marketed studied green tea in the metropolitan area of San Jose, Costa Rica has been really green tea good quality, this can be ensured by the findings in the analysis and comparison of the different profiles of flavonoids, polyphenols, alkaloids and amino acids. The antimicrobial activity has been without to confirmed in the bands of catechins analyzed [es

  12. Antioxidant and prooxidant properties of caffeine, theobromine and xanthine.

    Science.gov (United States)

    Azam, Sonish; Hadi, Naghma; Khan, Nizam Uddin; Hadi, Sheikh Mumtaz

    2003-09-01

    Caffeine, along with its catabolic products theobromine and xanthine, is a key component of tea and coffee. These compounds are structurally similar to uric acid, a known antioxidant which is present in blood at relatively high concentrations, but also shows prooxidant activity. In view of the structural similarity between uric acid and caffeine and its metabolites, we studied the antioxidant and prooxidant properties of these compounds. Antioxidant activity was determined by measuring the quenching effect of the compounds on oxidative DNA degradation by a hydroxyl radical generating system. Prooxidant activity was studied by measuring the ability of the compounds to oxidatively degrade DNA in the presence of copper ions. Caffeine, theobromine and xanthine have a quenching effect on the production of hydroxyl radicals, as well as on oxidative DNA breakage by hydroxyl radicals. Consistent with previous observations that many known antioxidants of plant origin are also capable of prooxidant action, the purine alkaloids also show oxidative DNA breakage in the presence of transition metal ions. The alkaloid caffeine and its catabolic products theobromine and xanthine exhibit both antioxidant and prooxidant properties. The results lead to the observation that caffeine and its metabolites may also contribute to the overall antioxidant and chemopreventive properties of caffeine-bearing beverages, such as tea.

  13. Caffeine Use among Active Duty Navy and Marine Corps Personnel

    Directory of Open Access Journals (Sweden)

    Joseph J. Knapik

    2016-10-01

    Full Text Available Data from the National Health and Nutrition Examination Survey (NHANES indicate 89% of Americans regularly consume caffeine, but these data do not include military personnel. This cross-sectional study examined caffeine use in Navy and Marine Corps personnel, including prevalence, amount of daily consumption, and factors associated with use. A random sample of Navy and Marine Corps personnel was contacted and asked to complete a detailed questionnaire describing their use of caffeine-containing substances, in addition to their demographic, military, and lifestyle characteristics. A total of 1708 service members (SMs completed the questionnaire. Overall, 87% reported using caffeinated beverages ≥1 time/week, with caffeine users consuming a mean ± standard error of 226 ± 5 mg/day (242 ± 7 mg/day for men, 183 ± 8 mg/day for women. The most commonly consumed caffeinated beverages (% users were coffee (65%, colas (54%, teas (40%, and energy drinks (28%. Multivariable logistic regression modeling indicated that characteristics independently associated with caffeine use (≥1 time/week included older age, white race/ethnicity, higher alcohol consumption, and participating in less resistance training. Prevalence of caffeine use in these SMs was similar to that reported in civilian investigations, but daily consumption (mg/day was higher.

  14. Caffeine Use among Active Duty Navy and Marine Corps Personnel

    Science.gov (United States)

    Knapik, Joseph J.; Trone, Daniel W.; McGraw, Susan; Steelman, Ryan A.; Austin, Krista G.; Lieberman, Harris R.

    2016-01-01

    Data from the National Health and Nutrition Examination Survey (NHANES) indicate 89% of Americans regularly consume caffeine, but these data do not include military personnel. This cross-sectional study examined caffeine use in Navy and Marine Corps personnel, including prevalence, amount of daily consumption, and factors associated with use. A random sample of Navy and Marine Corps personnel was contacted and asked to complete a detailed questionnaire describing their use of caffeine-containing substances, in addition to their demographic, military, and lifestyle characteristics. A total of 1708 service members (SMs) completed the questionnaire. Overall, 87% reported using caffeinated beverages ≥1 time/week, with caffeine users consuming a mean ± standard error of 226 ± 5 mg/day (242 ± 7 mg/day for men, 183 ± 8 mg/day for women). The most commonly consumed caffeinated beverages (% users) were coffee (65%), colas (54%), teas (40%), and energy drinks (28%). Multivariable logistic regression modeling indicated that characteristics independently associated with caffeine use (≥1 time/week) included older age, white race/ethnicity, higher alcohol consumption, and participating in less resistance training. Prevalence of caffeine use in these SMs was similar to that reported in civilian investigations, but daily consumption (mg/day) was higher. PMID:27735834

  15. Caffeine Use among Active Duty Navy and Marine Corps Personnel.

    Science.gov (United States)

    Knapik, Joseph J; Trone, Daniel W; McGraw, Susan; Steelman, Ryan A; Austin, Krista G; Lieberman, Harris R

    2016-10-09

    Data from the National Health and Nutrition Examination Survey (NHANES) indicate 89% of Americans regularly consume caffeine, but these data do not include military personnel. This cross-sectional study examined caffeine use in Navy and Marine Corps personnel, including prevalence, amount of daily consumption, and factors associated with use. A random sample of Navy and Marine Corps personnel was contacted and asked to complete a detailed questionnaire describing their use of caffeine-containing substances, in addition to their demographic, military, and lifestyle characteristics. A total of 1708 service members (SMs) completed the questionnaire. Overall, 87% reported using caffeinated beverages ≥1 time/week, with caffeine users consuming a mean ± standard error of 226 ± 5 mg/day (242 ± 7 mg/day for men, 183 ± 8 mg/day for women). The most commonly consumed caffeinated beverages (% users) were coffee (65%), colas (54%), teas (40%), and energy drinks (28%). Multivariable logistic regression modeling indicated that characteristics independently associated with caffeine use (≥1 time/week) included older age, white race/ethnicity, higher alcohol consumption, and participating in less resistance training. Prevalence of caffeine use in these SMs was similar to that reported in civilian investigations, but daily consumption (mg/day) was higher.

  16. Extraction of radioactive cesium from tea leaves

    International Nuclear Information System (INIS)

    Yano, Yukiko; Kubo, M. Kenya; Higaki, Shogo; Hirota, Masahiro; Nomura, Kiyoshi

    2011-01-01

    Radioactive contamination of foodstuffs attributed to the Fukushima Daiichi nuclear disaster has become a social problem. This study investigated the extraction of radioactive cesium from the contaminated leaves to the tea. The green tea was brewed twice reusing the same leaves to study the difference in extraction of cesium between the first and second brew. Moreover, the extraction of cesium was studied in correlation to brewing time. The concentration of radioactive cesium was determined with gamma spectrometry, and the concentration of caffeine was determined with absorption spectrometry. About 40% of cesium was extracted from leaves in the first brew, and about 80% was extracted in the second brew. The extraction of cesium increased over time, and it reached about 80% after 10 minutes brew. The ratio of radioactive cesium to caffeine decreased linearly over time. This study revealed that the extraction of cesium was higher for the second brew, and a rapid increase in extraction was seen as the tea was brewed for 6 minutes and more. Therefore, the first brew of green tea, which was brewed within 5 minutes, contained the least extraction of radioactive cesium from the contaminated leaves. (author)

  17. The legend of laphet: A Myanmar fermented tea leaf

    Directory of Open Access Journals (Sweden)

    Thazin Han

    2015-12-01

    Conclusion: Fermentation is the traditional method. Epigallocatechin gallate is a powerful constituent of laphet for human health. Its caffeinated effect is also popular in Myanmar society. This study will contribute to understanding Myanmar fermented tea leaves and spread the legend of laphet around the world.

  18. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D.

    2016-01-01

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51–70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000) to 142 mg/day (2011–2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes. PMID:26978391

  19. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location.

    Science.gov (United States)

    Drewnowski, Adam; Rehm, Colin D

    2016-03-10

    New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES) were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011-2012 data (n = 7456). Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011-2012, children aged four to eight years consumed the least caffeine (15 mg/day), and adults aged 51-70 years consumed the most (213 mg/day). The population mean (age ≥ four years) was 135 mg/day, driven largely by coffee (90 mg/day), tea (25 mg/day), and soda (21 mg/day). For the 14-19 years and 20-34 years age-groups, energy drinks contributed 6 mg/day (9.9%) and 5 mg/day (4.5%), respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999-2000) to 142 mg/day (2011-2012), largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day). Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

  20. Sources of Caffeine in Diets of US Children and Adults: Trends by Beverage Type and Purchase Location

    Directory of Open Access Journals (Sweden)

    Adam Drewnowski

    2016-03-01

    Full Text Available New sources of caffeine, besides coffee and tea, have been introduced into the US food supply. Data on caffeine consumption age and purchase location can help guide public health policy. National Health and Nutrition Examination Surveys (NHANES were used to estimate population-level caffeine intakes, using data from 24-h dietary recall. First, caffeine intakes by age-group and beverage type were estimated using the most recent 2011–2012 data (n = 7456. Second, fourteen years trends in caffeine consumption, overall and by beverage type, were evaluated for adults and children. Trend analyses were conducted by age groups. Last, trends in caffeine intakes by purchase location and beverage type were estimated. In 2011–2012, children aged four to eight years consumed the least caffeine (15 mg/day, and adults aged 51–70 years consumed the most (213 mg/day. The population mean (age ≥ four years was 135 mg/day, driven largely by coffee (90 mg/day, tea (25 mg/day, and soda (21 mg/day. For the 14–19 years and 20–34 years age-groups, energy drinks contributed 6 mg/day (9.9% and 5 mg/day (4.5%, respectively. The bulk of caffeine came from store-bought coffee and tea. Among both children and adults combined, caffeine intakes declined from 175 mg/day (1999–2000 to 142 mg/day (2011–2012, largely driven by a drop in caffeine from soda (41 mg/day to 21 mg/day. Store-bought coffee and tea remain principal drivers of caffeine intake in the US. Sodas and energy drinks make minor contributions to overall caffeine intakes.

  1. Addition of milk to tea infusions: Helpful or harmful? Evidence from in vitro and in vivo studies on antioxidant properties.

    Science.gov (United States)

    Rashidinejad, Ali; Birch, E John; Sun-Waterhouse, Dongxiao; Everett, David W

    2017-10-13

    Tea consumption is practised as a tradition, and has shown potential to improve human health. Maximal uptake of tea antioxidants and milk proteins without a negative impact on tea flavor is highly desired by consumers. There is a conflicting evidence of the effect of milk addition to tea on antioxidant activity. Differences in the type of tea, the composition, type and amount of milk, preparation method of tea-milk infusions, the assays used to measure antioxidant activity, and sampling size likely account for different findings. Interactions between tea polyphenols and milk proteins, especially between catechins and caseins, could account for a decrease in antioxidant activity, although other mechanisms are also possible, given the similar effects between soy and bovine milk. The role of milk fat globules and the milk fat globule membrane surface is also important when considering interactions and loss of polyphenolic antioxidant activity, which has not been addressed in the literature.

  2. Influence of black tea concentrate on kombucha fermentation

    Directory of Open Access Journals (Sweden)

    Malbaša Radomir V.

    2006-01-01

    Full Text Available Kombucha is cultivated on substrates prepared with different concentrations of black tea and substrate obtained by diluting a substrate with highest concentration of black tea with cold tap water. Qualify of produced beverages is compared with the beverage obtained in traditional fermentation of 1.5 g/L of black tea, sweetened with 70 g/L of sucrose. Inoculation was performed with 10% (v/v of fermentation liquid from previous process, and the fermentation was carried out at 28°C under aerobic conditions, for ten days. Process of fermentation was monitored by following pH, total acids. D-gluconic acid and caffeine content. Beverages obtained in fermentation with diluted black tea concentrate had similar amounts of investigated metabolites compared with traditional one. Use of diluted black tea concentrate as a substrate needs the shorter time for the substrate preparation, which significantly saves energy.

  3. Energy drink consumption and impact on caffeine risk.

    Science.gov (United States)

    Thomson, Barbara M; Campbell, Donald M; Cressey, Peter; Egan, Ursula; Horn, Beverley

    2014-01-01

    The impact of caffeine from energy drinks occurs against a background exposure from naturally occurring caffeine (coffee, tea, cocoa and foods containing these ingredients) and caffeinated beverages (kola-type soft drinks). Background caffeine exposure, excluding energy drinks, was assessed for six New Zealand population groups aged 15 years and over (n = 4503) by combining concentration data for 53 caffeine-containing foods with consumption information from the 2008/09 New Zealand Adult Nutrition Survey (ANS). Caffeine exposure for those who consumed energy drinks (n = 138) was similarly assessed, with inclusion of energy drinks. Forty-seven energy drink products were identified on the New Zealand market in 2010. Product volumes ranged from 30 to 600 ml per unit, resulting in exposures of 10-300 mg caffeine per retail unit consumed. A small percentage, 3.1%, of New Zealanders reported consuming energy drinks, with most energy drink consumers (110/138) drinking one serving per 24 h. The maximum number of energy drinks consumed per 24 h was 14 (total caffeine of 390 mg). A high degree of brand loyalty was evident. Since only a minor proportion of New Zealanders reported consuming energy drinks, a greater number of New Zealanders exceeded a potentially adverse effect level (AEL) of 3 mg kg(-1) bw day(-1) for caffeine from caffeine-containing foods than from energy drinks. Energy drink consumption is not a risk at a population level because of the low prevalence of consumption. At an individual level, however, teenagers, adults (20-64 years) and females (16-44 years) were more likely to exceed the AEL by consuming energy drinks in combination with caffeine-containing foods.

  4. Metabolomics analysis reveals the metabolic and functional roles of flavonoids in light-sensitive tea leaves.

    Science.gov (United States)

    Zhang, Qunfeng; Liu, Meiya; Ruan, Jianyun

    2017-03-20

    As the predominant secondary metabolic pathway in tea plants, flavonoid biosynthesis increases with increasing temperature and illumination. However, the concentration of most flavonoids decreases greatly in light-sensitive tea leaves when they are exposed to light, which further improves tea quality. To reveal the metabolism and potential functions of flavonoids in tea leaves, a natural light-sensitive tea mutant (Huangjinya) cultivated under different light conditions was subjected to metabolomics analysis. The results showed that chlorotic tea leaves accumulated large amounts of flavonoids with ortho-dihydroxylated B-rings (e.g., catechin gallate, quercetin and its glycosides etc.), whereas total flavonoids (e.g., myricetrin glycoside, epigallocatechin gallate etc.) were considerably reduced, suggesting that the flavonoid components generated from different metabolic branches played different roles in tea leaves. Furthermore, the intracellular localization of flavonoids and the expression pattern of genes involved in secondary metabolic pathways indicate a potential photoprotective function of dihydroxylated flavonoids in light-sensitive tea leaves. Our results suggest that reactive oxygen species (ROS) scavenging and the antioxidation effects of flavonoids help chlorotic tea plants survive under high light stress, providing new evidence to clarify the functional roles of flavonoids, which accumulate to high levels in tea plants. Moreover, flavonoids with ortho-dihydroxylated B-rings played a greater role in photo-protection to improve the acclimatization of tea plants.

  5. Green tea polyphenols extend the lifespan of male drosophila melanogaster while impairing reproductive fitness.

    Science.gov (United States)

    Lopez, Terry; Schriner, Samuel E; Okoro, Michael; Lu, David; Chiang, Beatrice T; Huey, Jocelyn; Jafari, Mahtab

    2014-12-01

    Green tea is a popular beverage believed to have many health benefits, including a reduction in the risks of heart disease and cancer. Rich in polyphenolic compounds known as catechins, green tea and its components have been shown to increase the lifespan of various animal models, including Drosophila melanogaster. Here, we investigated the gender-specific effects of green tea on the lifespan of fruit flies and observed that green tea extended the lifespan of male flies only. This effect was found to be independent of typical aging interventions, such as dietary restriction, modulation of oxidative energy metabolism, and improved tolerance to environmental stresses. The one exception was that green tea did protect male flies against iron toxicity. Since there is an inverse correlation between lifespan and reproduction, the impact of green tea on male reproductive fitness was also investigated. We found that green tea negatively impacted male fertility as shown by a reduced number of offspring produced and increased mating latency. We further identified that the lifespan extension properties of green tea was only observed in the presence of females which alludes to a reproductive (or mating) dependent mechanism. Our findings suggest that green tea extends the lifespan of male flies by inhibiting reproductive potential, possibly by limiting iron uptake. To our knowledge, our study is the first to report the negative impact of green tea on Drosophila male reproduction. Our results also support previous studies that suggest that green tea might have a negative effect on reproductive fitness in humans.

  6. Sleep-disordered breathing and caffeine consumption: results of a community-based study.

    Science.gov (United States)

    Aurora, R Nisha; Crainiceanu, Ciprian; Caffo, Brian; Punjabi, Naresh M

    2012-09-01

    Sleepiness is one of the most burdensome symptoms of sleep-disordered breathing (SDB). While caffeine is frequently used to avert sleepiness, the association between SDB and caffeine use has not been thoroughly explored. The current study examined whether SDB is associated with caffeine consumption and if factors such as sex, age, and daytime sleepiness explain or modify the association. Data from the Sleep Heart Health Study, a community-based study on the consequences of SDB, were used to characterize the association between SDB and caffeine intake. SDB was assessed with full-montage polysomnography. Caffeine use was quantified as the number of cans of soda or the cups of coffee or tea consumed daily. The Epworth Sleepiness Scale was used to assess daytime sleepiness. Multivariable negative binomial regression models were used to characterize the independent association between SDB and caffeine use. Caffeinated soda, but not tea or coffee, intake was independently associated with SDB severity. Compared with participants without SDB, the relative ratios for caffeinated soda consumption in women with mild, moderate, and severe SDB were 1.20 (CI, 1.03-1.41), 1.46 (CI, 1.14-1.87), and 1.73 (CI, 1.23-2.42), respectively. For men, an association was only noted with severe SDB and caffeinated soda use. Age did not modify the SDB-caffeine association, and sleepiness could not explain the observed associations. SDB is independently associated with caffeinated soda use in the general community. Identifying excessive caffeine used in SDB has potential significance given the cardiovascular effects of caffeine and untreated SDB.

  7. Synthesis and Property of Ag(NP)/catechin/Gelatin Nanofiber

    Science.gov (United States)

    Nasir, Muhamad; Apriani, Dita

    2017-12-01

    Nanomaterial play important role future industry such as for the medical, food, pharmaceutical and cosmetic industry. Ag (NP) and catechin exhibit antibacterial property. Ag(NP) with diameter around 15 nm was synthesis by microwaved method. We have successfully produce Ag(NP)/catechin/gelatin nanofiber composite by electrospinning process. Ag(NP)/catechin/gelatin nanofiber was synthesized by using gelatin from tuna fish, polyethylene oxide (PEO), acetic acid as solvent and silver nanoparticle(NP)/catechin as bioactive component, respectively. Morphology and structure of bioactive catechin-gelatin nanofiber were characterized by scanning electron microscopy (SEM) and fourier transform infrared spectroscopy (FTIR), respectively. SEM analysis showed that morphology of nanofiber composite was smooth and had average diameter 398.97 nm. FTIR analysis results were used to confirm structure of catechin-gelatin nanofiber. It was confirmed by FTIR that specific vibration band peak amide A (N-H) at 3286,209 cm-1, amide B (N-H) 3069,396 cm-1, amide I (C=O) at 1643,813 cm-1, amide II (N-H and CN) at 1538,949 cm-1, amide III (C-N) at 1276,789 cm-1, C-O-C from polyethylene oxide at 1146,418 cm-1, respectively. When examined to S. Aureus bacteria, Ag/catechin/gelatin nanofiber show inhabitation performance around 40.44%. Ag(NP)/catechin/gelatin nanofiber has potential application antibacterial medical application.

  8. Theacrine (1,3,7,9-tetramethyluric acid) synthesis in leaves of a Chinese tea, kucha (Camellia assamica var. kucha).

    Science.gov (United States)

    Zheng, Xin-Qiang; Ye, Chuang-Xing; Kato, Misako; Crozier, Alan; Ashihara, Hiroshi

    2002-05-01

    Theacrine (1,3,7,9-tetramethyluric acid) and caffeine were the major purine alkaloids in the leaves of an unusual Chinese tea known as kucha (Camellia assamica var. kucha). Endogenous levels of theacrine and caffeine in expanding buds and young leaves were ca. 2.8 and 0.6-2.7% of the dry wt, respectively, but the concentrations were lower in the mature leaves. Radioactivity from S-adenosyl-L-[methyl-14C]methionine was incorporated into theacrine as well as theobromine and caffeine by leaf disks of kucha, indicating that S-adenosyl-L-methionine acts as the methyl donor not only for caffeine biosynthesis but also for theacrine production. [8-14C]Caffeine was converted to theacrine by kucha leaves with highest incorporation occurring in expanding buds. When [8-14C]adenosine, the most effective purine precursor for caffeine biosynthesis in tea (Camellia sinensis), was incubated with young kucha leaves for 24 h, up to 1% of total radioactivity was recovered in theacrine. However, pulse-chase experiments with [8-14C]adenosine demonstrated much more extensive incorporation of label into caffeine than theacrine, possibly because of dilution of [14C]caffeine produced by the large endogenous caffeine pool. These results indicate that in kucha leaves theacrine is synthesized from caffeine in what is probably a three-step pathway with 1,3,7-methyluric acid acting an intermediate. This is a first demonstration that theacrine is synthesized from adenosine via caffeine.

  9. Green Tea as an Agricultural Based Health Promoting Food: The Past Five to Ten Years

    Directory of Open Access Journals (Sweden)

    Qin-Yin Shi

    2012-12-01

    Full Text Available The consumption of tea originated in ancient China over 4000 years ago and is currently the second most popular beverage in the world after water. Tea is an aromatic beverage prepared by pouring hot water over cured leaves of the Camellia sinensis plant. The link between tea intake, most notably green tea, and health has resulted in intense research on the components responsible for preventing the onset of several chronic diseases, including atherosclerosis, cancer, obesity and diabetes. In particular, the high levels of chemically diverse phenols (e.g., phenolic acids, flavonoids present in tea exhibit potent protective properties against many of these diseases. Although health related research on green tea and its predominant phenol (catechins has been on-going for decades, major advances have occurred in the last 5–10 years. Therefore, this review focuses on seminal studies reported primarily within the last five years but not extending past ten years on the link between health and green tea with an emphasis on the catechins.

  10. Metabolic phenotyping of various tea (Camellia sinensis L.) cultivars and understanding of their intrinsic metabolism.

    Science.gov (United States)

    Ji, Hyang-Gi; Lee, Yeong-Ran; Lee, Min-Seuk; Hwang, Kyeong Hwan; Kim, Eun-Hee; Park, Jun Seong; Hong, Young-Shick

    2017-10-15

    Recently, we selected three tea (Camellia sinensis) cultivars that are rich in taste, epigallocatechin-3-O-gallate (EGCG) and epigallocatechin-3-O-(3-O-methyl)-gallate (EGCG3″Me) and then cultivated them through asexual propagation by cutting in the same region. In the present study, proton nuclear magnetic resonance ( 1 H NMR)-based metabolomics was applied to characterize the metabotype and to understand the metabolic mechanism of these tea cultivars including wild type tea. Of the tea leaf metabolite variations, reverse associations of amino acid metabolism with catechin compound metabolism were found in the rich-taste, and EGCG- and EGCG3″Me-rich tea cultivars. Indeed, the metabolism of individual catechin compounds in the EGCG3″Me-rich cultivar differed from those of other tea cultivars. The current study highlights the distinct metabolism of various tea cultivars newly selected for cultivation and the important role of metabolomics in understanding the metabolic mechanism. Thus, comprehensive metabotyping is a useful method to assess and then develop a new plant cultivar. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Trends in caffeine intake among U.S. children and adolescents.

    Science.gov (United States)

    Branum, Amy M; Rossen, Lauren M; Schoendorf, Kenneth C

    2014-03-01

    Physicians and policy makers are increasingly interested in caffeine intake among children and adolescents in the advent of increasing energy drink sales. However, there have been no recent descriptions of caffeine or energy drink intake in the United States. We aimed to describe trends in caffeine intake over the past decade among US children and adolescents. We assessed trends and demographic differences in mean caffeine intake among children and adolescents by using the 24-hour dietary recall data from the 1999-2010 NHANES. In addition, we described the proportion of caffeine consumption attributable to different beverages, including soda, energy drinks, and tea. Approximately 73% of children consumed caffeine on a given day. From 1999 to 2010, there were no significant trends in mean caffeine intake overall; however, caffeine intake decreased among 2- to 11-year-olds (P Coffee accounted for 10% of caffeine intake in 1999-2000 but increased to nearly 24% of intake in 2009-2010 (P coffee and energy drinks represent a greater proportion of caffeine intake as soda intake has declined. These findings provide a baseline for caffeine intake among US children and young adults during a period of increasing energy drink use.

  12. An intervention study on the effect of matcha tea, in drink and snack bar formats, on mood and cognitive performance

    NARCIS (Netherlands)

    Dietz, Christina; Dekker, Matthijs; Piqueras-Fiszman, Betina

    2017-01-01

    Matcha tea is gaining popularity throughout the world in recent years and is frequently referred to as a mood-and-brain food. Previous research has demonstrated that three constituents present in matcha tea, l-theanine, epigallocatechin gallate (EGCG), and caffeine, affect mood and cognitive

  13. Aspirin, Butalbital, and Caffeine

    Science.gov (United States)

    The combination of aspirin, butalbital, and caffeine comes as a capsule and tablet to take by mouth. It usually is taken every 4 ... explain any part you do not understand. Take aspirin, butalbital, and caffeine exactly as directed. Do not ...

  14. Caffeine, cognitive failures and health in a non-working community sample.

    Science.gov (United States)

    Smith, Andrew P

    2009-01-01

    Most studies of the effects of caffeine on performance have been conducted in the laboratory and further information is required on the real-life effects of caffeine consumption on cognition. In addition, possible effects of caffeine consumption on a range of health outcomes should also be assessed in these studies to enable cost-benefit analyses to be conducted. Secondary analyses of a large epidemiological database (N = 3223 non-working participants, 57% female, with a mean age of 49.6 years, range 17-92 years) were conducted to examine associations between caffeine consumption (mean caffeine consumption was 140 mg/day, range 0-1800 mg) and cognitive failures (errors of memory, attention and action) in a non-working sample. Associations between caffeine consumption and physical and mental health problems were also examined. The study involved secondary analyses of a database formed by combining the Bristol Stress and Health at Work and Cardiff Health and Safety at Work studies. Associations between caffeine consumption and frequency of cognitive failures and health outcomes were examined in a sample of non-workers. After controlling for possible confounding factors significant associations between caffeine consumption and fewer cognitive failures were observed. Initial analyses suggested that many health variables were associated with regular level of caffeine consumption. However, most of the significant effects of caffeine disappeared when demographic and lifestyle factors were controlled for. Consumption of caffeine was, however, associated with a reduced risk of depression. These effects were also observed in separate analyses examining the source of the caffeine (coffee and tea). Overall, the results show that caffeine consumption may benefit cognitive functioning in a non-working population. This confirms earlier findings from working samples. This beneficial effect of caffeine was not associated with negative health consequences. Indeed, consumption of

  15. White tea (Camellia sinensis extract reduces oxidative stress and triacylglycerols in obese mice

    Directory of Open Access Journals (Sweden)

    Lílian Gonçalves Teixeira

    2012-12-01

    Full Text Available White tea is an unfermented tea made from young shoots of Camellia sinensis protected from sunlight to avoid polyphenol degradation. Although its levels of catechins are higher than those of green tea (derived from the same plant, there are no studies addressing the relationship between this tea and obesity associated with oxidative stress.The objective of this study was to evaluate the effect of white tea on obesity and its complications using a diet induced obesity model. Forty male C57BL/6 mice were fed a high-fat diet to induce obesity (Obese group or the same diet supplemented with 0.5% white tea extract (Obese + WTE for 8 weeks. Adipose tissue, serum lipid profile, and oxidative stress were studied. White tea supplementation was not able to reduce food intake, body weight, or visceral adiposity. Similarly, there were no changes in cholesterol rich lipoprotein profile between the groups. A reduction in blood triacylglycerols associated with increased cecal lipids was observed in the group fed the diet supplemented with white tea. White tea supplementation also reduced oxidative stress in liver and adipose tissue. In conclusion, white tea extract supplementation (0.5% does not influence body weight or adiposity in obese mice. Its benefits are restricted to the reduction in oxidative stress associated with obesity and improvement of hypertriacylglycerolemia.

  16. Molecular and biochemical characterization of caffeine synthase and purine alkaloid concentration in guarana fruit.

    Science.gov (United States)

    Schimpl, Flávia Camila; Kiyota, Eduardo; Mayer, Juliana Lischka Sampaio; Gonçalves, José Francisco de Carvalho; da Silva, José Ferreira; Mazzafera, Paulo

    2014-09-01

    Guarana seeds have the highest caffeine concentration among plants accumulating purine alkaloids, but in contrast with coffee and tea, practically nothing is known about caffeine metabolism in this Amazonian plant. In this study, the levels of purine alkaloids in tissues of five guarana cultivars were determined. Theobromine was the main alkaloid that accumulated in leaves, stems, inflorescences and pericarps of fruit, while caffeine accumulated in the seeds and reached levels from 3.3% to 5.8%. In all tissues analysed, the alkaloid concentration, whether theobromine or caffeine, was higher in young/immature tissues, then decreasing with plant development/maturation. Caffeine synthase activity was highest in seeds of immature fruit. A nucleotide sequence (PcCS) was assembled with sequences retrieved from the EST database REALGENE using sequences of caffeine synthase from coffee and tea, whose expression was also highest in seeds from immature fruit. The PcCS has 1083bp and the protein sequence has greater similarity and identity with the caffeine synthase from cocoa (BTS1) and tea (TCS1). A recombinant PcCS allowed functional characterization of the enzyme as a bifunctional CS, able to catalyse the methylation of 7-methylxanthine to theobromine (3,7-dimethylxanthine), and theobromine to caffeine (1,3,7-trimethylxanthine), respectively. Among several substrates tested, PcCS showed higher affinity for theobromine, differing from all other caffeine synthases described so far, which have higher affinity for paraxanthine. When compared to previous knowledge on the protein structure of coffee caffeine synthase, the unique substrate affinity of PcCS is probably explained by the amino acid residues found in the active site of the predicted protein. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Caffeine Use and Extroversion.

    Science.gov (United States)

    Landrum, R. Eric; Meliska, Charles J.

    Some research on the stimulant effect of caffeine suggests that the amount of behavioral enhancement produced by caffeine may depend on subjects' prior experience with the task and the drug. A study was undertaken to test whether prior experience with a task while under the influence of caffeine would facilitate performance of that task. Male…

  18. Caffeine, fatigue, and cognition

    NARCIS (Netherlands)

    Lorist, M.M.; Tops, M.

    2003-01-01

    Effects of caffeine and fatigue are discussed with special attention to adenosine-dopamine interactions. Effects of caffeine on human cognition are diverse. Behavioural measurements indicate a general improvement in the efficiency of information processing after caffeine, while the EEG data support

  19. DETERMINATION OF CAFFEIN MINATION OF CAFFEINE ...

    African Journals Online (AJOL)

    userpc

    disturbance and the effect of caffeine on sleep is highly variable, (Peters and Josef, 1967). This research is aimed at determining and comparing the caffeine contents of the old and fresh kola nut(Cola acuminate) from the southern part of Nigeria referred to as 'Dan. Ikko' meaning the Lagos variety, while kola nut from Ghana ...

  20. Bioactive compounds in green tea leaves attenuate the injury of retinal ganglion RGC-5 cells induced by H2O2 and ultraviolet radiation.

    Science.gov (United States)

    Jin, Jianchang; Ying, Hao; Huang, Meirong; Du, Qizhen

    2015-11-01

    The Chinese commonly believe that tea helps maintain clear vision. This viewpoint has been recorded in Chinese medical books also. The key bioactive compounds in green tea leaves, (-)-epigallocatechin gallate (EGCG), L-theanine (theanine) and caffeine, were investigated for their abilities to attenuate the injury of retinal ganglion cells (RGC-5) induced by H2O2 and ultraviolet radiation. Theanine and caffeine promoted cell growth while concentrations of EGCG greater than 10μg/ml inhibited cell growth. The nine and caffeine both protected RGC-5 cells from injury as well as enhanced their recovery, while EGCG only protected the cells from injury and did not help them to recover. Tea is a unique drink, which is simultaneously enriched with EGCG, theanine and caffeine. The role of these compounds in optic nerve protection may partially explain why some tea drinkers feel enhanced vision.

  1. Green tea and its anti-angiogenesis effects.

    Science.gov (United States)

    Rashidi, Bahman; Malekzadeh, Mehrnoush; Goodarzi, Mohammad; Masoudifar, Aria; Mirzaei, Hamed

    2017-05-01

    The development of new blood vessels from a pre-existing vasculature (also known as angiogenesis) is required for many physiological processes including embryogenesis and post-natal growth. However, pathological angiogenesis is also a hallmark of cancer and many ischaemic and inflammatory diseases. The pro-angiogenic members of the VEGF family (vascular endothelial growth factor family), VEGF-A, VEGF-B, VEGF-C, VEGF-D and placental growth factor (PlGF), and the related receptors, VEGFR-1, VEGFR-2 and VEGFR-3 have a central and decisive role in angiogenesis. Indeed, they are the targets for anti-angiogenic drugs currently approved. Green tea (from the Camellia sinensis plant) is one of the most popular beverages in the world. It is able to inhibit angiogenesis by different mechanisms such as microRNAs (miRNAs). Green tea and its polyphenolic substances (like catechins) show chemo-preventive and chemotherapeutic features in various types of cancer and experimental models for human cancers. The tea catechins, including (-)-epigallocatechin-3-gallate (EGCG), have multiple effects on the cellular proteome and signalome. Note that the polyphenolic compounds from green tea are able to change the miRNA expression profile associated with angiogenesis in various cancer types. This review focuses on the ability of the green tea constituents to suppress angiogenesis signaling and it summarizes the mechanisms by which EGCG might inhibit the VEGF family. We also highlighted the miRNAs affected by green tea which are involved in anti-angiogenesis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. The effects of L-theanine, caffeine and their combination on cognition and mood.

    Science.gov (United States)

    Haskell, Crystal F; Kennedy, David O; Milne, Anthea L; Wesnes, Keith A; Scholey, Andrew B

    2008-02-01

    L-Theanine is an amino acid found naturally in tea. Despite the common consumption of L-theanine, predominantly in combination with caffeine in the form of tea, only one study to date has examined the cognitive effects of this substance alone, and none have examined its effects when combined with caffeine. The present randomised, placebo-controlled, double-blind, balanced crossover study investigated the acute cognitive and mood effects of L-theanine (250 mg), and caffeine (150 mg), in isolation and in combination. Salivary caffeine levels were co-monitored. L-Theanine increased 'headache' ratings and decreased correct serial seven subtractions. Caffeine led to faster digit vigilance reaction time, improved Rapid Visual Information Processing (RVIP) accuracy and attenuated increases in self-reported 'mental fatigue'. In addition to improving RVIP accuracy and 'mental fatigue' ratings, the combination also led to faster simple reaction time, faster numeric working memory reaction time and improved sentence verification accuracy. 'Headache' and 'tired' ratings were reduced and 'alert' ratings increased. There was also a significant positive caffeine x L-theanine interaction on delayed word recognition reaction time. These results suggest that beverages containing L-theanine and caffeine may have a different pharmacological profile to those containing caffeine alone.

  3. Tea and coffee intake in relation to risk of breast cancer in the Black Women's Health Study.

    Science.gov (United States)

    Boggs, Deborah A; Palmer, Julie R; Stampfer, Meir J; Spiegelman, Donna; Adams-Campbell, Lucile L; Rosenberg, Lynn

    2010-11-01

    Prospective studies of tea and coffee intake and breast cancer risk have yielded inconsistent results. None of these studies has reported separately on African-American women. We prospectively examined the relation of tea and coffee consumption to risk of breast cancer among 52,062 women aged 21-69 at enrollment in 1995 in the Black Women's Health Study. Dietary intake was assessed in 1995 and 2001 using a validated food frequency questionnaire. Cox proportional hazards models were used to estimate incidence rate ratios (IRR) and 95% confidence intervals (CI), adjusted for breast cancer risk factors. During 12 years of follow-up through 2007, there were 1,268 incident cases of breast cancer. Intakes of tea, coffee, and caffeine were not significantly associated with the risk of breast cancer overall. The IRRs for consumption of ≥4 cups/day compared with none were 1.13 (95% CI 0.78-1.63) for tea and 1.03 (95% CI 0.77-1.39) for caffeinated coffee, and the IRR for the top quintile relative to the bottom quintile of caffeine intake was 1.04 (95% CI 0.87-1.24). Consumption of tea, coffee, and caffeine was not significantly associated with breast cancer risk according to menopausal status or hormone receptor status. Our findings suggest that intakes of tea, coffee, and caffeine are not associated with the risk of breast cancer among African-American women.

  4. The effect of caffeine consumption on the success rate of pregnancy as well various performance parameters of in-vitro fertilization treatment.

    Science.gov (United States)

    Al-Saleh, Iman; El-Doush, Inaam; Grisellhi, Bellido; Coskun, Serdar

    2010-12-01

    This study evaluated the effect of caffeine consumption on the success rate of pregnancy and various in vitro fertilization (IVF) performance parameters. Serum and follicular fluid samples were collected from 619 women undergoing IVF treatment (2002-2003). Caffeine assessment was based on measuring the levels of caffeine in serum and follicular fluid and on the number of coffee or tea or caffeinated drinks consumed per day. A total of 97.3% of participants reported the consumption of caffeinated drinks such as coffee, tea and soft drinks. Their average caffeine consumption was 455.82 mg/day (range: 3.71-3561 mg/day). Coffee was the primary source of caffeine intake. The average caffeine levels in serum (0.913 µg/ml) were significantly higher than in follicular fluid (0.701 µg/ml). After controlling for various potential confounding variables, no association was found between coffee or tea consumption and the success rate of pregnancy. Looking at the effect of caffeine consumption on the IVF performance parameters, we found that the number of eggs decreased as the caffeine serum levels increased (P=0.011). An increase in coffee consumption was positively associated with the number of aborted pregnancy (P=0.007), while the number of good embryo decreased with high tea consumption (P=0.015). Though no association was seen between coffee or tea consumption and pregnancy rate, this study is the first to report that caffeine can reach the follicular fluid and there is a suggestive evidence of its possible harmful role on the consequences of reproductive process. This clearly warrants further investigation.

  5. Behavioural effects of compounds co-consumed in dietary forms of caffeinated plants.

    Science.gov (United States)

    Haskell, C F; Dodd, F L; Wightman, E L; Kennedy, D O

    2013-06-01

    Research into the cognitive and mood effects of caffeine in human subjects has highlighted some fairly robust and well-accepted effects. However, the majority of these studies have focused on caffeine in isolation; whilst caffeine is normally consumed in the form of plant-derived products and extracts that invariably contain other potentially bioactive phytochemicals. The aim of the present review is to consider the possible mechanisms of action of co-occurring phytochemicals, and any epidemiological evidence suggesting that they contribute to potential health benefits ascribed to caffeine. Intervention studies to date that have been conducted to explore the effects on brain function of the non-caffeine components in caffeine-bearing plants (coffee, tea, cocoa, guaraná), either alone or in combination with caffeine, will also be summarised. Research is beginning to accumulate showing independent effects for several of the phytochemicals that co-occur with caffeine, and/or a modulation of the effects of caffeine when it is co-consumed with these naturally concomitant phytochemicals. The present review highlights that more research aimed at understanding the effects of these compounds is needed and, more importantly, the synergistic relationship that they may have with caffeine.

  6. Caffeine and exercise.

    Science.gov (United States)

    Paluska, Scott A

    2003-08-01

    Caffeine is the most commonly consumed drug in the world, and athletes frequently use it as an ergogenic aid. It improves performance and endurance during prolonged, exhaustive exercise. To a lesser degree it also enhances short-term, high-intensity athletic performance. Caffeine improves concentration, reduces fatigue, and enhances alertness. Habitual intake does not diminish caffeine's ergogenic properties. Several mechanisms have been proposed to explain the physiologic effects of caffeine, but adenosine receptor antagonism most likely accounts for the primary mode of action. It is relatively safe and has no known negative performance effects, nor does it cause significant dehydration or electrolyte imbalance during exercise. Routine caffeine consumption may cause tolerance or dependence, and abrupt discontinuation produces irritability, mood shifts, headache, drowsiness, or fatigue. Major sport governing bodies ban excessive use of caffeine, but current monitoring techniques are inadequate, and ethical dilemmas persist regarding caffeine intake by athletes.

  7. Caffeine: Friend or Foe?

    Science.gov (United States)

    Doepker, Candace; Lieberman, Harris R; Smith, Andrew Paul; Peck, Jennifer D; El-Sohemy, Ahmed; Welsh, Brian T

    2016-01-01

    The debate on the safety of and regulatory approaches for caffeine continues among various stakeholders and regulatory authorities. This decision-making process comes with significant challenges, particularly when considering the complexities of the available scientific data, making the formulation of clear science-based regulatory guidance more difficult. To allow for discussions of a number of key issues, the North American Branch of the International Life Sciences Institute (ILSI) convened a panel of subject matter experts for a caffeine-focused session entitled "Caffeine: Friend or Foe?," which was held during the 2015 ILSI Annual Meeting. The panelists' expertise covered topics ranging from the natural occurrence of caffeine in plants and interindividual metabolism of caffeine in humans to specific behavioral, reproductive, and cardiovascular effects related to caffeine consumption. Each presentation highlighted the potential risks, benefits, and challenges that inform whether caffeine exposure warrants concern. This paper aims to summarize the key topics discussed during the session.

  8. Aluminium and nutrients induce changes in the profiles of phenolic substances in tea plants (Camellia sinensis CV TTES, No. 12 (TTE)).

    Science.gov (United States)

    Chen, Yue Ming; Tsao, Tsung Ming; Liu, Cheng Chung; Lin, Kuo Chuan; Wang, Ming Kuang

    2011-04-01

    Tea plants are always cultivated in acid soils in hilly regions and their growth can be dependent on to soluble aluminium (Al). The mechanism of Al detoxification and the influence of Al on phenolic compounds (i.e. catechin) in the roots of tea plants has remained obscure. This study aimed to investigate the influence of Al changes on the concentrations of phenolic substances in tea plants through hydroponic experiments. Tea plants were cultivated in nutrient solution containing 1.5 and 2.5 mmol L(-1) Al, and these treatments enhanced the growth of new buds and roots. Aluminium stimulated the uptake of Ca, Mg, K and Mn, whereas the uptake of Fe, Cu and Zn was retarded. Moreover, total phenol concentrations in tea plant tissues increased with increasing Al concentrations. In general, catechin concentrations in leaves increased with increasing Al concentrations in the hydroponic experiments. High correlation coefficients were obtained between Al and (-)-ECG (r(2) = 0.85, P < 0.01) and between Al and total phenols (r(2) = 0.92, P < 0.01). The Al concentration in tea plants indeed increases catechin concentrations and plays an important role in the growth of tea plants. Copyright © 2011 Society of Chemical Industry.

  9. Plasma appearance and correlation between coffee and green tea metabolites in human subjects.

    Science.gov (United States)

    Renouf, Mathieu; Guy, Philippe; Marmet, Cynthia; Longet, Karin; Fraering, Anne-Lise; Moulin, Julie; Barron, Denis; Dionisi, Fabiola; Cavin, Christophe; Steiling, Heike; Williamson, Gary

    2010-12-01

    Coffee and green tea are two of the most widely consumed hot beverages in the world. Their respective bioavailability has been studied separately, but absorption of their respective bioactive phenolics has not been compared. In a randomised cross-over design, nine healthy subjects drank instant coffee and green tea. Blood samples were collected over 12 h and at 24 h to assess return to baseline. After green tea consumption, (-)-epigallocatechin (EGC) was the major catechin, appearing rapidly in the plasma; (-)-EGC gallate (EGCg) and (-)-epicatechin (EC) were also present, but (-)-EC gallate and C were not detected. Dihydroferulic acid and dihydrocaffeic acid were the major metabolites that appeared after coffee consumption with a long time needed to reach maximum plasma concentration, suggesting metabolism and absorption in the colon. Other phenolic acid equivalents (caffeic acid (CA), ferulic acid (FA) and isoferulic acid (iFA)) were detected earlier, and they peaked at lower concentrations. Summations of the plasma area under the curves (AUC) for the measured metabolites showed 1.7-fold more coffee-derived phenolic acids than green tea-derived catechins (P = 0.0014). Furthermore, we found a significant correlation between coffee metabolites based on AUC. Inter-individual differences were observed, but individuals with a high level of CA also showed a correspondingly high level of FA. However, no such correlation was observed between the tea catechins and coffee phenolic acids. Correlation between AUC and maximum plasma concentration was also significant for CA, FA and iFA and for EGCg. This implies that the mechanisms of absorption for these two classes of compounds are different, and that a high absorber of phenolic acids is not necessarily a high absorber of catechins.

  10. Caffeinated beverage intake and reproductive hormones among premenopausal women in the BioCycle Study.

    Science.gov (United States)

    Schliep, Karen C; Schisterman, Enrique F; Mumford, Sunni L; Pollack, Anna Z; Zhang, Cuilin; Ye, Aijun; Stanford, Joseph B; Hammoud, Ahmad O; Porucznik, Christina A; Wactawski-Wende, Jean

    2012-02-01

    Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood. We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race. Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented. Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = -0.15; 95% CI: -0.26, -0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively. Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race.

  11. Caffeinated beverage intake and reproductive hormones among premenopausal women in the BioCycle Study123

    Science.gov (United States)

    Schisterman, Enrique F; Mumford, Sunni L; Pollack, Anna Z; Zhang, Cuilin; Ye, Aijun; Stanford, Joseph B; Hammoud, Ahmad O; Porucznik, Christina A; Wactawski-Wende, Jean

    2012-01-01

    Background: Caffeinated beverages are widely consumed among women of reproductive age, but their association with reproductive hormones, and whether race modifies any such associations, is not well understood. Objective: We assessed the relation between caffeine and caffeinated beverage intake and reproductive hormones in healthy premenopausal women and evaluated the potential effect modification by race. Design: Participants (n = 259) were followed for up to 2 menstrual cycles and provided fasting blood specimens for hormonal assessment at up to 8 visits per cycle and four 24-h dietary recalls per cycle. Weighted linear mixed models and nonlinear mixed models with harmonic terms were used to estimate associations between caffeine and hormone concentrations, adjusted for age, adiposity, physical activity, energy and alcohol intakes, and perceived stress. On the basis of a priori assumptions, an interaction between race and caffeine was tested, and stratified results are presented. Results: Caffeine intake ≥200 mg/d was inversely associated with free estradiol concentrations among white women (β = −0.15; 95% CI: −0.26, −0.05) and positively associated among Asian women (β = 0.61; 95% CI: 0.31, 0.92). Caffeinated soda intake and green tea intake ≥1 cup/d (1 cup = 240 mL) were positively associated with free estradiol concentrations among all races: β = 0.14 (95% CI: 0.06, 0.22) and β = 0.26 (95% CI: 0.07, 0.45), respectively. Conclusions: Moderate consumption of caffeine was associated with reduced estradiol concentrations among white women, whereas caffeinated soda and green tea intakes were associated with increased estradiol concentrations among all races. Further research is warranted on the association between caffeine and caffeinated beverages and reproductive hormones and whether these relations differ by race. PMID:22237060

  12. Swelling and infusion of tea in tea bags.

    Science.gov (United States)

    Yadav, Geeta U; Joshi, Bhushan S; Patwardhan, Ashwin W; Singh, Gurmeet

    2017-07-01

    The present study deals with swelling and infusion kinetics of tea granules in tea bags. The swelling and infusion kinetics of tea bags differing in tea loading and tea bag shapes were compared with loose tea. Increment in temperature and dipping frequency of tea bag in hot water increased the infusion kinetics of tea bags. Reduction in particle size enhanced the swelling and infusion kinetics of tea in a tea bag. The effects of tea particle size, tea bag dipping rate, loading of tea granules in tea bag and tea bag shapes on infusion kinetics were investigated. Increase in tea loading in tea bags resulted in reduced infusion kinetics. Double chambered tea bag showed the highest swelling (30%) and infusion kinetics (8.30% Gallic acid equivalence) while single chambered tea bags showed the lowest kinetics, amongst the various bags studied. The swelling and infusion kinetics of loose tea was always faster and higher than that of tea bags. It was found that overall effect of percentage filling of tea granules and height of tea bed in a tea bag affects tea infusion kinetics the most. Weibull model was found to be in good agreement with the swelling data.

  13. A prospective study of caffeine and coffee intake and premenstrual syndrome.

    Science.gov (United States)

    Purdue-Smithe, Alexandra C; Manson, JoAnn E; Hankinson, Susan E; Bertone-Johnson, Elizabeth R

    2016-08-01

    Clinically significant premenstrual syndrome (PMS) affects 15-20% of premenopausal women, substantially reducing quality of life. Women with PMS often are counseled to minimize caffeine intake, although only limited evidence supports this recommendation. We evaluated the association between total caffeine, coffee, and tea intake and the development of PMS in a case-control study nested within the prospective Nurses' Health Study II. All participants were free from PMS at baseline (1991). PMS cases reported a new clinician-made diagnosis of PMS on biennial questionnaires between 1993 and 2005, and then confirmed symptom timing and moderate-to-severe impact and severity of symptoms with the use of a retrospective questionnaire (n = 1234). Controls did not report PMS and confirmed experiencing no symptoms or few mild symptoms with limited personal impact (n = 2426). Caffeine, coffee, and tea intake was measured by food-frequency questionnaires every 4 y, and data on smoking, body weight, and other factors were updated every 2-4 y. Logistic regression was used to evaluate the associations of total caffeine intake and frequency of coffee and tea consumption with PMS. After adjustment for age, smoking, and other factors, total caffeine intake was not associated with PMS. The OR comparing women with the highest (quintile median = 543 mg/d) to the lowest (quintile median = 18 mg/d) caffeine intake was 0.79 (95% CI: 0.61, 1.04; P-trend = 0.31). High caffeinated coffee intake also was not associated with risk of PMS or specific symptoms, including breast tenderness (OR for ≥4 cups/d compared with caffeine intake is not associated with PMS, and that current recommendations for women to reduce caffeine intake may not help prevent the development of PMS. © 2016 American Society for Nutrition.

  14. Mechanisms of Body Weight Reduction and Metabolic Syndrome Alleviation by Tea

    Science.gov (United States)

    Yang, Chung S.; Zhang, Jinsong; Zhang, Le; Huang, Jinbao; Wang, Yijun

    2016-01-01

    Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been shown to reduce body weight, alleviate metabolic syndrome, and prevent diabetes and cardiovascular diseases in animal models and humans. Such beneficial effects have generally been observed in most human studies when the level of tea consumption was 3 to 4 cups (600–900 mg tea catechins) or more per day. Green tea is more effective than black tea. In spite of numerous studies, the fundamental mechanisms for these actions still remain unclear. From a review of the literature, we propose that the two major mechanisms are: 1) decreasing absorption of lipids and proteins by tea constituents in the intestine, thus reducing calorie intake; and 2) activating AMPK by tea polyphenols that are bioavailable in the liver, skeletal muscle, and adipose tissues. The relative importance of these two mechanisms depends on the types of tea and diet consumed by individuals. The activated AMPK would decrease gluconeogenesis and fatty acid synthesis and increase catabolism, leading to body weight reduction and MetS alleviation. Other mechanisms and the health relevance of these beneficial effects of tea consumption remain to be further investigated. PMID:26577614

  15. Caffeine Consumption, Expectancies of Caffeine-Enhanced Performance, and Caffeinism Symptoms among University Students.

    Science.gov (United States)

    Bradley, John R.; Petree, Allen

    1990-01-01

    Gathered self-report data on college students' (n=797) expectations of caffeine-enhanced performance, level of beverage caffeine consumed daily, and caffeinism signs experienced after consumption of caffeinated beverages. Results supported extending the expectancies model of substance use motivation from alcohol to caffeine. (Author/ABL)

  16. Optimization of Ultrasonic Extraction of Phenolic Antioxidants from Green Tea Using Response Surface Methodology

    OpenAIRE

    Lee, Lan-Sook; Lee, Namhyouck; Kim, Young; Lee, Chang-Ho; Hong, Sang; Jeon, Yeo-Won; Kim, Young-Eon

    2013-01-01

    Response surface methodology (RSM) has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 °C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio ...

  17. EFFECT OF CAFFEINE ON THE HUMAN BODY: A REVIEW

    Directory of Open Access Journals (Sweden)

    Sadia Hafeez Kazi

    2015-06-01

    Full Text Available Caffeine (1,3,7-trimethylxanthine is the widely consumed substance all over the world. It is found in coffee, tea, cocoa, etc. Caffeine (CF is rapidly and completely absorbed from the gastrointestinal tract; peak plasma concentration reaches in about 15 to 120 min after oral ingestion in humans without any significant first-pass effect. There are some drugs which are responsible for the inhibition of metabolism of CF. It also exerts its effect in higher doses on different body organs like neuro, gastrointestinal, renal, respiration, skeletal muscle, cardiovascular systems. Those who are regular consumer of tea, coffee, or CF containing beverages are at the higher risk for the development of CF toxicity which can lead even to death of an individual. The dependence and withdrawal side effects of CF include anxiety, insomnia, restlessness, nervousness, tremors, gastrointestinal upset, tachycardia, psychomotor agitation, etc.

  18. Metabolite Profiling of 14 Wuyi Rock Tea Cultivars Using UPLC-QTOF MS and UPLC-QqQ MS Combined with Chemometrics

    Directory of Open Access Journals (Sweden)

    Si Chen

    2018-01-01

    Full Text Available Wuyi Rock tea, well-recognized for rich flavor and long-lasting fragrance, is a premium subcategory of oolong tea mainly produced in Wuyi Mountain and nearby regions of China. The quality of tea is mainly determined by the chemical constituents in the tea leaves. However, this remains underexplored for Wuyi Rock tea cultivars. In this study, we investigated the leaf metabolite profiles of 14 major Wuyi Rock tea cultivars grown in the same producing region using UPLC-QTOF MS and UPLC-QqQ MS with data processing via principal component analysis and cluster analysis. Relative quantitation of 49 major metabolites including flavan-3-ols, proanthocyanidins, flavonol glycosides, flavone glycosides, flavonone glycosides, phenolic acid derivatives, hydrolysable tannins, alkaloids and amino acids revealed clear variations between tea cultivars. In particular, catechins, kaempferol and quercetin derivatives were key metabolites responsible for cultivar discrimination. Information on the varietal differences in the levels of bioactive/functional metabolites, such as methylated catechins, flavonol glycosides and theanine, offers valuable insights to further explore the nutritional values and sensory qualities of Wuyi Rock tea. It also provides potential markers for tea plant fingerprinting and cultivar identification.

  19. Metabolite Profiling of 14 Wuyi Rock Tea Cultivars Using UPLC-QTOF MS and UPLC-QqQ MS Combined with Chemometrics.

    Science.gov (United States)

    Chen, Si; Li, Meihong; Zheng, Gongyu; Wang, Tingting; Lin, Jun; Wang, Shanshan; Wang, Xiaxia; Chao, Qianlin; Cao, Shixian; Yang, Zhenbiao; Yu, Xiaomin

    2018-01-24

    Wuyi Rock tea, well-recognized for rich flavor and long-lasting fragrance, is a premium subcategory of oolong tea mainly produced in Wuyi Mountain and nearby regions of China. The quality of tea is mainly determined by the chemical constituents in the tea leaves. However, this remains underexplored for Wuyi Rock tea cultivars. In this study, we investigated the leaf metabolite profiles of 14 major Wuyi Rock tea cultivars grown in the same producing region using UPLC-QTOF MS and UPLC-QqQ MS with data processing via principal component analysis and cluster analysis. Relative quantitation of 49 major metabolites including flavan-3-ols, proanthocyanidins, flavonol glycosides, flavone glycosides, flavonone glycosides, phenolic acid derivatives, hydrolysable tannins, alkaloids and amino acids revealed clear variations between tea cultivars. In particular, catechins, kaempferol and quercetin derivatives were key metabolites responsible for cultivar discrimination. Information on the varietal differences in the levels of bioactive/functional metabolites, such as methylated catechins, flavonol glycosides and theanine, offers valuable insights to further explore the nutritional values and sensory qualities of Wuyi Rock tea. It also provides potential markers for tea plant fingerprinting and cultivar identification.

  20. Metabolic engineering of Saccharomyces cerevisiae for caffeine and theobromine production.

    Science.gov (United States)

    Jin, Lu; Bhuiya, Mohammad Wadud; Li, Mengmeng; Liu, XiangQi; Han, Jixiang; Deng, WeiWei; Wang, Min; Yu, Oliver; Zhang, Zhengzhu

    2014-01-01

    Caffeine (1, 3, 7-trimethylxanthine) and theobromine (3, 7-dimethylxanthine) are the major purine alkaloids in plants, e.g., tea (Camellia sinensis) and coffee (Coffea arabica). Caffeine is a major component of coffee and is used widely in food and beverage industries. Most of the enzymes involved in the caffeine biosynthetic pathway have been reported previously. Here, we demonstrated the biosynthesis of caffeine (0.38 mg/L) by co-expression of Coffea arabica xanthosine methyltransferase (CaXMT) and Camellia sinensis caffeine synthase (TCS) in Saccharomyces cerevisiae. Furthermore, we endeavored to develop this production platform for making other purine-based alkaloids. To increase the catalytic activity of TCS in an effort to increase theobromine production, we identified four amino acid residues based on structural analyses of 3D-model of TCS. Two TCS1 mutants (Val317Met and Phe217Trp) slightly increased in theobromine accumulation and simultaneously decreased in caffeine production. The application and further optimization of this biosynthetic platform are discussed.

  1. Metabolic engineering of Saccharomyces cerevisiae for caffeine and theobromine production.

    Directory of Open Access Journals (Sweden)

    Lu Jin

    Full Text Available Caffeine (1, 3, 7-trimethylxanthine and theobromine (3, 7-dimethylxanthine are the major purine alkaloids in plants, e.g., tea (Camellia sinensis and coffee (Coffea arabica. Caffeine is a major component of coffee and is used widely in food and beverage industries. Most of the enzymes involved in the caffeine biosynthetic pathway have been reported previously. Here, we demonstrated the biosynthesis of caffeine (0.38 mg/L by co-expression of Coffea arabica xanthosine methyltransferase (CaXMT and Camellia sinensis caffeine synthase (TCS in Saccharomyces cerevisiae. Furthermore, we endeavored to develop this production platform for making other purine-based alkaloids. To increase the catalytic activity of TCS in an effort to increase theobromine production, we identified four amino acid residues based on structural analyses of 3D-model of TCS. Two TCS1 mutants (Val317Met and Phe217Trp slightly increased in theobromine accumulation and simultaneously decreased in caffeine production. The application and further optimization of this biosynthetic platform are discussed.

  2. Caffeine-containing beverages, total fluid consumption, and premenstrual syndrome.

    Science.gov (United States)

    Rossignol, A M; Bonnlander, H

    1990-09-01

    The main objective of this study was to evaluate whether daily consumption of caffeine-containing beverages is related to the prevalence and severity of premenstrual syndrome apart from any effects of daily total fluid consumption. A secondary objective was to determine whether daily total fluid consumption itself is related to premenstrual syndrome. The study is based on 841 responses to a questionnaire probing menstrual and premenstrual health, and daily fluid consumption, which was mailed to female university students in Oregon. Analysis of the data revealed that consumption of caffeine-containing beverages was strongly related to the prevalence of premenstrual syndrome. Among women with more severe symptoms, the relation between consumption of caffeine-containing beverages and premenstrual syndrome was dose-dependent, with prevalence odds ratios equal to 1.3 for consumers of one cup of a caffeine-containing beverage per day and increasing steadily to 7.0 for consumers of eight to 10 cups per day. The effects were apparent among both caffeine-containing tea/coffee consumers and caffeine-containing soda consumers. The observed effects were only slightly reduced when daily total fluid consumption was controlled. Daily total fluid consumption also was related to the prevalence of premenstrual symptoms although the effects were large only for consumers of 13-19 cups of fluid per day (the largest amount studied).

  3. Colletotrichum gloeosporioides- Contaminated Tea Infusion Blocks Lipids Reduction and Induces Kidney Damage in Mice

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    Jin Li

    2017-10-01

    Full Text Available When the homogenate of fresh tea tree leaves was fermented to produce black tea beverage, the Colletotrichum gloeosporioides (main pathogen or endophyte of Camellia sinensis may be mixed into the fermentation liquor. However, it was unclear whether C. gloeosporioides-contaminated tea beverage would damage human health. Therefore, we investigated the changes of functional components and the influences on mice. C. gloeosporioides was added to the green tea infusion. After cultivation of 48 h, tea polyphenols, caffeine, and L-theanine decreased by 31.0, 26.2, and 8.3%, respectively. The contaminated tea infusion showed brown stain, and produced a group of toxic materials named phthalic acid esters. The animal study showed that green tea without contamination significantly decreased levels of alanine aminotransferase, triglycerides, free fatty acids, low-density lipoprotein, and increased insulin level compared with obese mice. On the contrary, contaminated tea lost the effects on these indicators. Furthermore, the urea nitrogen and serum creatinine levels significantly increased in the contaminated tea-drinking mice. Altogether, our results indicate that C. gloeosporioides contamination can reduce the amount of functional components of green tea. Therefore, it inhibits some health-care function of lipid-lowering. In addition, the toxic components in contaminated tea infusion might induce renal damage.

  4. Tea aroma formation

    Directory of Open Access Journals (Sweden)

    Chi-Tang Ho

    2015-03-01

    Full Text Available Besides water, tea is one of the most popular beverages around the world. The chemical ingredients and biological activities of tea have been summarized recently. The current review summarizes tea aroma compounds and their formation in green, black, and oolong tea. The flavor of tea can be divided into two categories: taste (non-volatile compounds and aroma (volatile compounds. All of these aroma molecules are generated from carotenoids, lipids, glycosides, etc. precursors, and also from Maillard reaction. In the current review, we focus on the formation mechanism of main aromas during the tea manufacturing process.

  5. Caffeine, fatigue, and cognition.

    Science.gov (United States)

    Lorist, Monicque M; Tops, Mattie

    2003-10-01

    Effects of caffeine and fatigue are discussed with special attention to adenosine-dopamine interactions. Effects of caffeine on human cognition are diverse. Behavioural measurements indicate a general improvement in the efficiency of information processing after caffeine, while the EEG data support the general belief that caffeine acts as a stimulant. Studies using ERP measures indicate that caffeine has an effect on attention, which is independent of specific stimulus characteristics. Behavioural effects on response related processes turned out to be mainly related to more peripheral motor processes. Recent insights in adenosine and dopamine physiology and functionality and their relationships with fatigue point to a possible modulation by caffeine of mechanisms involved in the regulation of behavioural energy expenditure.

  6. Simultaneous activation of salicylate production and fungal resistance in transgenic chrysanthemum producing caffeine

    Science.gov (United States)

    Kim, Yun-Soo; Lim, Soon; Yoda, Hiroshi; Choi, Chang-Sun; Choi, Yong-Eui

    2011-01-01

    Caffeine functions in the chemical defense against biotic attackers in a few plant species including coffee and tea. Transgenic tobacco plants that endogenously produced caffeine by expressing three N-methyltransferases involved in the caffeine biosynthesis pathway exhibited a strong resistance to pathogens and herbivores. Here we report that transgenic Chrysanthemum, which produced an equivalent level of caffeine as the tobacco plants at approximately 3 µg g−1 fresh tissues, also exhibited a resistance against grey mold fungal attack. Transcripts of PR-2 gene, a marker for pathogen response, were constitutively accumulated in mature leaves without pathogen attack. The levels of salicylic acid and its glucoside conjugate in mature leaves of the transgenic lines were found to be 2.5-fold higher than in the wild type control. It is suggested that endogenous caffeine stimulated production and/or deposition of salicylates, which possibly activated a series of defense reactions even under non-stressed conditions. PMID:21346420

  7. The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness.

    Science.gov (United States)

    Giesbrecht, T; Rycroft, J A; Rowson, M J; De Bruin, E A

    2010-12-01

    The non-proteinic amino acid L-theanine and caffeine, a methylxanthine derivative, are naturally occurring ingredients in tea. The present study investigated the effect of a combination of 97 mg L-theanine and 40 mg caffeine as compared to placebo treatment on cognitive performance, alertness, blood pressure, and heart rate in a sample of young adults (n = 44). Cognitive performance, self-reported mood, blood pressure, and heart rate were measured before L-theanine and caffeine administration (i.e. at baseline) and 20 min and 70 min thereafter. The combination of moderate levels of L-theanine and caffeine significantly improved accuracy during task switching and self-reported alertness (both P effects on other cognitive tasks, such as visual search, choice reaction times, or mental rotation. The present results suggest that 97 mg of L-theanine in combination with 40 mg of caffeine helps to focus attention during a demanding cognitive task.

  8. Green tea chemoprotection in rats treated with Diethylnitrosamine
    Ação quimioprotetora do chá verde em ratos tratados com Dietilnitrosamina

    OpenAIRE

    Halha Ostrensky Saridakis; Alexandre Saito; Rubens Cecchini; Dirceu Estevão; Wanderlei Onofre Schmitz

    2011-01-01

    Green tea (Camellia sinensis) and its main components, the catechins present several biological activities such as: antioxidant and chemoprotective action against hepatotoxic agent as diethylnitrosamine(DEN), a known cytotoxic substance. This work has the objective to evaluate and understand the green tea extract (GTE) mechanisms of action as a chemoprotector agent. Therefore, tests in vivo with Wistar rats using GTE 2% (2mg/100mL) was taken orally as the only source of water for 35 days. To ...

  9. Coffee and tea consumption, genotype-based CYP1A2 and NAT2 activity and colorectal cancer risk—Results from the EPIC cohort study

    NARCIS (Netherlands)

    Dik, V.K.; Bueno-de-Mesquita, H.B.; Oijen, van M.G.C.T.; Siersema, P.D.; Uiterwaal, C.S.P.M.; Gils, van C.H.; Duijnhoven, van F.J.B.

    2014-01-01

    Coffee and tea contain numerous antimutagenic and antioxidant components and high levels of caffeine that may protect against colorectal cancer (CRC). We investigated the association between coffee and tea consumption and CRC risk and studied potential effect modification by CYP1A2 and NAT2

  10. Coffee and tea consumption and risk of pre- and postmenopausal breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study

    NARCIS (Netherlands)

    Bhoo-Pathy, Nirmala; Peeters, Petra H M; Uiterwaal, Cuno S P M; Bueno-de-Mesquita, H. Bas; Bulgiba, Awang M.; Bech, Hammer H.; Overvad, Kim; Tjønneland, Anne; Olsen, Anja; Clavel-Chapelon, Françoise; Fagherazzi, Guy; Perquier, Florence; Teucher, Birgit; Kaaks, Rudolf; Schütze, Madlen; Boeing, Heiner; Lagiou, Pagona; Orfanos, Philippos; Trichopoulou, Antonia; Agnoli, Claudia; Mattiello, Amalia; Palli, Domenico; Tumino, Rosario; Sacerdote, Carlotta; Van Duijnhoven, Franzel J B; Braaten, Tonje; Lund, Eiliv; Skeie, Guri; Redondo, María Luisa; Buckland, Genevieve; Pérez, Sánchez J S; Chirlaque, Maria Dolores; Ardanaz, Eva; Amiano, Pilar; Wirfält, Elisabet; Wallström, Peter; Johansson, Ingegerd; Nilsson, Maria M.; Khaw, Kay Tee; Wareham, Nick; Allen, Naomi E.; Key, Timothy J.; Rinaldi, Sabina; Romieu, Isabelle; Gallo, Valentina; Riboli, Elio; Van Gils, Carla H.

    2015-01-01

    Introduction: Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer. Methods: A total of 335,060 women participating in the

  11. Coffee and tea consumption and risk of pre- and postmenopausal breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study

    NARCIS (Netherlands)

    Bhoo-Pathy, Nirmala; Peeters, Petra H.M.; Uiterwaal, Cuno S.P.M.; Duijnhoven, van F.J.B.

    2015-01-01

    Introduction: Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer. Methods: A total of 335,060 women participating in the

  12. Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: a systematic review.

    Science.gov (United States)

    Astorino, Todd A; Roberson, Daniel W

    2010-01-01

    Caffeine is the most widely used drug in the world, commonly ingested in coffee, tea, soda, and energy drinks. Its ability to enhance muscular work has been apparent since the early 1900s. Caffeine typically increases endurance performance; however, efficacy of caffeine ingestion for short-term high-intensity exercise is equivocal, which may be explained by discrepancies in exercise protocols, dosing, and subjects' training status and habitual caffeine intake found across studies. The primary aim of this review is to critically examine studies that have tested caffeine's ability to augment performance during exercise dependent on nonoxidative metabolism such as sprinting, team sports, and resistance training. A review of the literature revealed 29 studies that measured alterations in short-term performance after caffeine ingestion. Each study was critically analyzed using the Physiotherapy Evidence Database (PEDro) scale. The mean PEDro score was 7.76 +/- 0.87. Eleven of 17 studies revealed significant improvements in team sports exercise and power-based sports with caffeine ingestion, yet these effects were more common in elite athletes who do not regularly ingest caffeine. Six of 11 studies revealed significant benefits of caffeine for resistance training. Some studies show decreased performance with caffeine ingestion when repeated bouts are completed. The exact mechanism explaining the ergogenic effect of caffeine for short-term exercise is unknown.

  13. Graphene platforms for the detection of caffeine in real samples.

    Science.gov (United States)

    Khoo, Weslie Yu Heng; Pumera, Martin; Bonanni, Alessandra

    2013-12-04

    The analysis of food components is of high importance due to food safety and security. Here the electrochemical detection of caffeine was performed on different chemically modified graphene (CMG) surfaces carrying diverse amount of defects and oxygen functionalities. The analytical performances of graphite oxide (GPO), graphene oxide (GO), and electrochemically reduced graphene oxide (ERGO) were compared for the first time for the detection of caffeine. It was found that ERGO showed the most favourable analytical parameters, such as lower oxidation potential, sensitivity, linearity and reproducibility of the response. ERGO was then used for the analysis of real samples. Caffeine levels of soluble coffee, teas and energetic drinks were measured without the need of any sample pre-treatment. Our findings are very important to gain more insight into the applicability of different graphene materials to real samples for sense-and-act analysis. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Metabolomic analysis using ultra-performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF MS uncovers the effects of light intensity and temperature under shading treatments on the metabolites in tea.

    Directory of Open Access Journals (Sweden)

    Qunfeng Zhang

    Full Text Available To investigate the effect of light intensity and temperature on the biosynthesis and accumulation of quality-related metabolites, field grown tea plants were shaded by Black Net and Nano-insulating Film (with additional 2-4°C cooling effect with un-shaded plants as a control. Young shoots were subjected to UPLC-Q-TOF MS followed by multivariate statistical analysis. Most flavonoid metabolites (mainly flavan-3-ols, flavonols and their glycosides decreased significantly in the shading treatments, while the contents of chlorophyll, β-carotene, neoxanthin and free amino acids, caffeine, benzoic acid derivatives and phenylpropanoids increased. Comparison between two shading treatments indicated that the lower temperature under Nano shading decreased flavonols and their glycosides but increased accumulation of flavan-3-ols and proanthocyanidins. The comparison also showed a greater effect of temperature on galloylation of catechins than light intensity. Taken together, there might be competition for substrates between the up- and down-stream branches of the phenylpropanoid/flavonoid pathway, which was influenced by light intensity and temperature.

  15. Free radical scavenging activity of Eagle tea and their flavonoids

    Directory of Open Access Journals (Sweden)

    Qiong Meng

    2012-06-01

    Full Text Available In this study, an online HPLC-DAD-MS coupled with 2,2′-azinobis (3-ethylbenzthiazoline-6-sulfonic acid diammonium salt (ABTS assay was employed for evaluating free radical scavenging activity of Eagle tea and their active components. Twenty-three chromatographic peaks were detected, and nineteen components had free radical scavenging activity. Among them, eight compounds were identified as flavonoids (hyperin, isoquercitrin, quercitrin, quercetin, kaempferol, catechins, chlorogenic acid and epicatechin based on MS data and standard chromatographic characters.

  16. Studies on prevention of obesity, metabolic syndrome, diabetes, cardiovascular diseases and cancer by tea

    Directory of Open Access Journals (Sweden)

    Chung Shu Yang

    2018-01-01

    Full Text Available Tea, a popular beverage made from leaves of the plant Camellia sinensis, has been studied extensively in recent decades for its beneficial health effects in the prevention of obesity, metabolic syndrome, diabetes, cancer, and other diseases. Whereas these beneficial effects have been convincingly demonstrated in most laboratory studies, results from human studies have not been consistent. Some studies demonstrated that weight reduction, alleviation of metabolic syndrome and risk reduction in diabetes were only observed in individuals who consume 3–4 cups of tea (600–900 mg tea catechins or more daily. This chapter reviews some of these studies, the possible mechanisms of actions of tea constituents, and the challenges in extrapolating laboratory studies to human situations.

  17. Polyphenolic Profile and Antioxidant Activities of Oolong Tea Infusion under Various Steeping Conditions

    Directory of Open Access Journals (Sweden)

    Feng Chen

    2007-11-01

    Full Text Available The phenolic profile and antioxidant activities of oolong tea extract wereinvestigated after tea was steeped in 90 or 100 oC water for 3 or 10 min. The extractionyield increased with increasing temperature and extended steeping time. However, highertemperature and longer time (100 oC water for 10 min led to loss of phenolics. Theaqueous extract of oolong tea (AEOT at 100 oC for 3 min exhibited the strongestantioxidant activity. The major polyphenolic components of the AEOT were identified as(--epigallocatechin (EGC, (--epigallocatechin gallate (EGCG and (--epicatechin-3-gallate (ECG. The two major catechins (EGC and EGCG in the tea infusion contributedsignificantly to the investigated antioxidant activities [i.e., the 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH radical scavenging and superoxide radical scavengingactivities] with high correlation values in r = 0.9486 and 0.9327 for the EGC and r =0.9592 and 0.8718 for the EGCG, respectively.

  18. Metabolomic unveiling of a diverse range of green tea (Camellia sinensis) metabolites dependent on geography.

    Science.gov (United States)

    Lee, Jang-Eun; Lee, Bum-Jin; Chung, Jin-Oh; Kim, Hak-Nam; Kim, Eun-Hee; Jung, Sungheuk; Lee, Hyosang; Lee, Sang-Jun; Hong, Young-Shick

    2015-05-01

    Numerous factors such as geographical origin, cultivar, climate, cultural practices, and manufacturing processes influence the chemical compositions of tea, in the same way as growing conditions and grape variety affect wine quality. However, the relationships between these factors and tea chemical compositions are not well understood. In this study, a new approach for non-targeted or global analysis, i.e., metabolomics, which is highly reproducible and statistically effective in analysing a diverse range of compounds, was used to better understand the metabolome of Camellia sinensis and determine the influence of environmental factors, including geography, climate, and cultural practices, on tea-making. We found a strong correlation between environmental factors and the metabolome of green, white, and oolong teas from China, Japan, and South Korea. In particular, multivariate statistical analysis revealed strong inter-country and inter-city relationships in the levels of theanine and catechin derivatives found in green and white teas. This information might be useful for assessing tea quality or producing distinct tea products across different locations, and highlights simultaneous identification of diverse tea metabolites through an NMR-based metabolomics approach. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Antioxidant properties of catechins: Comparison with other antioxidants.

    Science.gov (United States)

    Grzesik, Michalina; Naparło, Katarzyna; Bartosz, Grzegorz; Sadowska-Bartosz, Izabela

    2018-02-15

    Antioxidant properties of five catechins and five other flavonoids were compared with several other natural and synthetic compounds and related to glutathione and ascorbate as key endogenous antioxidants in several in vitro tests and assays involving erythrocytes. Catechins showed the highest ABTS-scavenging capacity, the highest stoichiometry of Fe 3+ reduction in the FRAP assay and belonged to the most efficient compounds in protection against SIN-1 induced oxidation of dihydrorhodamine 123, AAPH-induced fluorescein bleaching and hypochlorite-induced fluorescein bleaching. Glutathione and ascorbate were less effective. (+)-catechin and (-)-epicatechin were the most effective compounds in protection against AAPH-induced erythrocyte hemolysis while (-)-epicatechin gallate, (-)-epigallocatechin gallate and (-)-epigallocatechin protected at lowest concentrations against hypochlorite-induced hemolysis. Catechins [(-)-epigallocatechin gallate and (-)-epicatechin gallate)] were most efficient in the inhibition of AAPH-induced oxidation of 2'7'-dichlorodihydroflurescein contained inside erythrocytes. Excellent antioxidant properties of catechins and other flavonoids make them ideal candidates for nanoformulations to be used in antioxidant therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Method for recovering aroma concentrate from a caffeine- or theobromine-comprising food base material

    NARCIS (Netherlands)

    Kattenberg, H.R.; Willemsen, J.H.A.; Starmans, D.A.J.; Hoving, H.D.; Winters, M.G.M.

    2002-01-01

    Described is a method for recovering aroma concentrate from a caffeine- or theobromine-comprising food base material, such as coffee or tea, and in particular cocoa, at least comprising the steps of: introducing the food base material into an aqueous extractant and incubating the food base material

  1. A comparative analysis of chemical compositions in Camellia sinensis var. puanensis Kurihara, a novel Chinese tea, by HPLC and UFLC-Q-TOF-MS/MS.

    Science.gov (United States)

    Li, Yi-Fang; Ouyang, Shu-Hua; Chang, Yi-Qun; Wang, Ting-Mei; Li, Wei-Xi; Tian, Hai-Yan; Cao, Hong; Kurihara, Hiroshi; He, Rong-Rong

    2017-02-01

    Camellia sinensis var. puanensis Kurihara (Puan tea) is a kind of ancient tea plant newly found in Jiangxipo and the surrounding areas of Puan County (Guizhou, China). People there always believe that drinking Puan tea is beneficial to the promotion of health and prevention of diseases. However, detailed information on its compositions has not been reported. Therefore, in this study, the varieties and contents of purine alkaloids and polyphenols in Puan tea were identified and determined by HPLC and UFLC-Q-TOF-MS/MS. Our results showed that theacrine, but not caffeine, was the dominated purine alkaloid detected in Puan tea. Meanwhile, Puan tea contained B-type procyanidin dimer, trimer and dimer monogallate, which were not detected in Camellia sinensis, Camellia ptilophylla and Camellia assamica var. kucha. The obtained results could support the local uses of Puan tea in health and nutrition and contribute to the research of tea variety. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Caffeine inhibits cell proliferation by G0/G1 phase arrest in JB6 cells.

    Science.gov (United States)

    Hashimoto, Takashi; He, Zhiwei; Ma, Wei-Ya; Schmid, Patricia C; Bode, Ann M; Yang, Chung S; Dong, Zigang

    2004-05-01

    Caffeine is a major biologically active constituent in coffee and tea. Because caffeine has been reported to inhibit carcinogenesis in UVB-exposed mice, the cancer-preventing effect of caffeine has attracted considerable attention. In the present study, the effect of caffeine in quiescent (G0 phase) cells was investigated. Pretreatment with caffeine suppressed cell proliferation in a dose-dependent manner 36 h after addition of fetal bovine serum as a cell growth stimulator. Analysis by flow cytometry showed that caffeine suppressed cell cycle progression at the G0/G1 phase, i.e., 18 h after addition of fetal bovine serum, the percentages of cells in G0/G1 phase in 1 mM caffeine-treated cells and in caffeine-untreated cells were 61.7 and 29.0, respectively. The percentage of cells in G0/G1 phase at 0 h was 75.5. Caffeine inhibited phosphorylation of retinoblastoma protein at Ser780 and Ser807/Ser811, the sites where retinoblastoma protein has been reported to be phosphorylated by cyclin-dependent kinase 4 (cdk4). Furthermore, caffeine inhibited the activation of the cyclin D1-cdk4 complex in a dose-dependent manner. However this compound did not directly inhibit the activity of this complex. In addition, caffeine did not affect p16INK4 or p27Kip1 protein levels, but inhibited the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase 3beta. Our results showed that caffeine suppressed the progression of quiescent cells into the cell cycle. The inhibitory mechanism may be due to the inhibition of cell growth signal-induced activation of cdk4, which may be involved in the inhibition of carcinogenesis in vivo.

  3. Caffeine (1, 3, 7-trimethylxanthine) in foods: a comprehensive review on consumption, functionality, safety, and regulatory matters.

    Science.gov (United States)

    Heckman, Melanie A; Weil, Jorge; Gonzalez de Mejia, Elvira

    2010-04-01

    Caffeine ranks as one of the top most commonly consumed dietary ingredients throughout the world. It is naturally found in coffee beans, cacao beans, kola nuts, guarana berries, and tea leaves including yerba mate. The total daily intake, as well as the major source of caffeine varies globally; however, coffee and tea are the 2 most prominent sources. Soft drinks are also a common source of caffeine as well as energy drinks, a category of functional beverages. Moderate caffeine consumption is considered safe and its use as a food ingredient has been approved, within certain limits, by numerous regulatory agencies around the world. Performance benefits attributed to caffeine include physical endurance, reduction of fatigue, and enhancing mental alertness and concentration. Caffeine has also been recently linked to weight loss and consequent reduction of the overall risks for developing the metabolic syndrome. However, the caloric contribution of caffeine-sweetened beverages needs to be considered in the overall energy balance. Despite all these benefits the potential negative effects of excessive caffeine intake should also be considered, particularly in children and pregnant women.

  4. Interaction of tea polyphenols with serum albumins: A fluorescence spectroscopic analysis

    International Nuclear Information System (INIS)

    Bose, Adity

    2016-01-01

    Interactions of some tea polyphenols, namely (−) Catechin (C), (−)-epicatechin (EC), (–) epicatechin-3-gallate (ECG), (−)-epigallocatechin (EGC) and (−)-epigallocatechin-3-gallate (EGCG) are outlined with the serum albumin proteins. These interactions had all resulted in binding with the proteins with a concomitant static quenching of the protein fluorescence. A fluorescence technique has been considered as the tool to comprehend the polyphenol–protein interactions mainly and simultaneously other spectroscopic techniques used to verify the results have been discussed. In this mini review the different types of equations usually employed to calculate the binding constant values have been outlined, namely, modified Stern Volmer plot, Scatchard plot and Lineweaver Burk equation, with their corresponding results. The n values (number of binding sites) had always been close to unity suggesting a 1:1 complexation with the polyphenols and the protein. A structural change in the polyphenols has been found to alter the binding constant value and the galloyl moiety attached to the C ring of the polyphenols have been found to play a crucial role in this regard. It has been found that an increase in galloyl moiety increases binding of the catechins with proteins. - Highlights: • Review on interactions of some tea polyphenols with the serum albumin proteins. • Tea polyphenols include Catechin, epigallocatechin-3-gallate, epigallocatechin, epicatechin-3-gallate and epicatechin. • Fluorescence spectroscopic technique is mainly outlined. • Binding constant studies have been given importance. • Galloyl moiety in the C ring is crucial in increasing binding constant.

  5. Heritability of caffeine metabolism

    DEFF Research Database (Denmark)

    Matthaei, Johannes; Tzvetkov, Mladen V; Strube, Jakob

    2016-01-01

    Heritability of caffeine pharmacokinetics and CYP1A2 activity is controversial. Here we analyzed the pharmacokinetics of caffeine, an in vivo probe drug for CYP1A2 and arylamine N-acetyltransferase 2 (NAT2) activity, in monozygotic and dizygotic twins. In the entire group, common and unique...... environmental effects explained most variation in caffeine AUC. Apparently, smoking and hormonal contraceptives masked the genetic effects on CYP1A2 activity. However, when excluding smokers and users of hormonal contraceptives, 89% of caffeine AUC variation was due to genetic effects and even in the entire...... group, 8% of caffeine AUC variation could be explained by a CYP1A1/1A2 promotor polymorphism (rs2470893). In contrast, nearly all of the variation (99%) of NAT2 activity was explained by genetic effects. This study illustrates two very different situations in pharmacogenetics, from an almost exclusively...

  6. Caffeine and adenosine.

    Science.gov (United States)

    Ribeiro, Joaquim A; Sebastião, Ana M

    2010-01-01

    Caffeine causes most of its biological effects via antagonizing all types of adenosine receptors (ARs): A1, A2A, A3, and A2B and, as does adenosine, exerts effects on neurons and glial cells of all brain areas. In consequence, caffeine, when acting as an AR antagonist, is doing the opposite of activation of adenosine receptors due to removal of endogenous adenosinergic tonus. Besides AR antagonism, xanthines, including caffeine, have other biological actions: they inhibit phosphodiesterases (PDEs) (e.g., PDE1, PDE4, PDE5), promote calcium release from intracellular stores, and interfere with GABA-A receptors. Caffeine, through antagonism of ARs, affects brain functions such as sleep, cognition, learning, and memory, and modifies brain dysfunctions and diseases: Alzheimer's disease, Parkinson's disease, Huntington's disease, Epilepsy, Pain/Migraine, Depression, Schizophrenia. In conclusion, targeting approaches that involve ARs will enhance the possibilities to correct brain dysfunctions, via the universally consumed substance that is caffeine.

  7. Black tea and maintenance of normal endotheliumdependent vasodilation: evaluation of a health claim pursuant to Article 13(5) of Regulation (EC) No 1924/2006

    DEFF Research Database (Denmark)

    Sjödin, Anders Mikael

    2018-01-01

    on the scientific substantiation of a health claim related to black tea and maintenance of normal endotheliumdependent vasodilation. The scope of the application was proposed to fall under a health claim based on newly developed scientific evidence. The food proposed by the applicant as the subject of the health...... claim is black tea beverages, either freshly prepared or reconstituted from water extract powders of black tea, characterised by the content of flavanols (expressed as catechins plus theaflavins) of at least 30 mg per 200 mL serving. The Panel considers that black tea characterised by the content....... Of the five human intervention studies provided on the chronic effect of black tea consumption on endothelium-dependent vasodilation, two investigated the effect after regular consumption of black tea for a sufficiently long time period (i.e. at least 4 weeks). These two studies did not allow an effect...

  8. Influences of charcoal and bamboo charcoal amendment on soil-fluoride fractions and bioaccumulation of fluoride in tea plants.

    Science.gov (United States)

    Gao, Hongjian; Zhang, Zhengzhu; Wan, Xiaochun

    2012-10-01

    High levels of fluoride in tea plants pose a potential health risk to humans who drink tea. It has been demonstrated that tea plant fluoride is closely related to the available fluoride in soil. But approaches that could be used to regulate the availability of fluoride in soil have been rarely seen. This study aims to investigate how the addition of charcoal and bamboo charcoal affected soil fluoride availability and bioaccumulation of fluoride in tea plants. In a microcosm experiment, tea plants were grown in the tea garden soil mixed with different amounts of charcoal and bamboo charcoal [that is, 0.5, 1.0, 2.5, and 5.0 % (w/w)]. Soil-fluoride fractions and fluoride accumulated in tea plants were determined using the sequential extraction and ion selective electrode method. Obtained results showed that both charcoal and bamboo charcoal additions significantly enhanced the concentrations of Fe/Mn oxide-bound fluoride, but significantly reduced the concentrations of water-soluble and exchangeable fluoride (p Charcoal and bamboo charcoal additions also significantly decreased the amounts of fluoride in tea roots and tea leaves (p charcoal and bamboo charcoal had no impacts on the tea quality, as indexed by the concentrations of polysaccharides, polyphenols, amino acids, and caffeine in tea leaves. These results suggested that application of charcoal and bamboo charcoal may provide a useful method to reduce the availability of fluoride in soil and the subsequent fluoride uptake by tea plants.

  9. Antioxidant Phenolic Compounds from Pu-erh Tea

    Directory of Open Access Journals (Sweden)

    Shu Shan Du

    2012-11-01

    Full Text Available Eight compounds were isolated from the water extract of Pu-erh tea and their structures were elucidated by NMR and MS as gallic acid (1, (+-catechin (2, (−-epicatechin (3, (−-epicatechin-3-O-gallate (4, (−-epigallocatechin-3-O-gallate (5, (−-epiafzelechin- 3-O-gallate (6, kaempferol (7, and quercetin (8. Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The relative order of DPPH scavenging capacity for these compounds was compound 8 > compound 7 > compound 1 > compound 6 > compound 4 ≈ compound 5 > compound 2 > VC (reference > compound 3, and that of ABTS scavenging capacity was compound 1 > compound 2 > compound 7 ≈ compound 8 > compound 6 > compound 5 > compound 4 > VC (reference > compound 3. The results showed that these phenolic compounds contributed to the antioxidant activity of Pu-erh tea.

  10. A naturalistic investigation of the effects of day-long consumption of tea, coffee and water on alertness, sleep onset and sleep quality.

    Science.gov (United States)

    Hindmarch, I; Rigney, U; Stanley, N; Quinlan, P; Rycroft, J; Lane, J

    2000-04-01

    The effects of caffeine, especially caffeinated coffee, on human performance have been extensively studied. However, few studies have been naturalistic representations of how tea/coffee is normally consumed in terms of dose and time of consumption. This study investigated the effects of day-long consumption of tea, coffee and water on cognitive and psychomotor performance, and sleep quality at night. Thirty healthy volunteers received equal volume drinks equivalent to either 1 or 2 cups of tea (containing 37.5 mg or 75 mg caffeine), or coffee (75 mg or 150 mg caffeine), or water, in a randomised five-way crossover design. Drinks were administered on four occasions during the day (0900, 1300, 1700 and 2300 hours). A psychometric battery consisting of critical flicker fusion (CFF), choice reaction time (CRT) and subjective sedation (LARS) tests, was administered pre-dose and at frequent time points post-dose. The Leeds Sleep Evaluation Questionnaire (LSEQ) was completed each morning and a wrist actigraph was worn for the duration of the study. Caffeinated beverages maintained CFF threshold over the whole day (Pcaffeine dose or beverage type. During the acute phase of beverage ingestion, caffeine significantly sustained performance compared to water after the first beverage for CFF and subjective sedation (Pcaffeine after the first drink. Compared to coffee, tea produced a significant increase in CFF threshold between 30 and 90 min post-consumption (Pcaffeinated coffee at 75 mg significantly improved reaction time (PCaffeinated beverages had a dose dependent negative effect on sleep onset (Psleep time (Psleep quality (Pcaffeinated beverages may maintain aspects of cognitive and psychomotor performance throughout the day and evening when caffeinated beverages are administered repeatedly. This study also demonstrates that day-long tea consumption produces similar alerting effects to coffee, despite lower caffeine levels, but is less likely to disrupt sleep. Other

  11. Polyphenolic content and antioxidant capacity of white, green, black, and herbal teas: a kinetic study

    Directory of Open Access Journals (Sweden)

    Shannon, E.,

    2017-08-01

    Full Text Available Camellia sinensis teas, and tisanes derived from herbs or fruit, are rich in polyphenolic, antioxidant compounds. This study compared the total phenolic content (TPC, total flavonoid content (TFC, ferric reducing antioxidant power (FRAP, DPPH radical scavenging capacity, and caffeine content of teas (black, green, white, chamomile, and mixed berry/hibiscus over a range of infusion times (0.5–10 mins at 90°C. Green, followed by black tea, respectively, had the greatest TPC (557.58 and 499.19μg GAE/g, TFC (367.84 and 325.18μg QE/g, FRAP (887.38 and 209.38μg TE/g, and DPPH radical scavenging capacity (1233.03 and 866.39μg AAE/g. Caffeine content per cup (200mL in black, green, and white tea was 63, 51, and 49mg respectively. Changes in the phenolic content and antioxidant capacity of teas were modelled using zero, first, and fractional-conversion-first-order (FCFO kinetic models. Results fitted a FCFO kinetic model, providing useful data for maximum phytochemical preservation in the optimisation of industrial and domestic processing. As a dietary comparison, green, black, and white tea were found to have a greater phenolic content and antioxidant capacity than fresh orange and apple juice. It can be concluded that green and black teas are significant sources of dietary phenolic antioxidants.

  12. Effects of L-theanine or caffeine intake on changes in blood pressure under physical and psychological stresses

    OpenAIRE

    Yoto, Ai; Motoki, Mao; Murao, Sato; Yokogoshi, Hidehiko

    2012-01-01

    Abstract Background L-theanine, an amino acid contained in green tea leaves, is known to block the binding of L-glutamic acid to glutamate receptors in the brain, and has been considered to cause anti-stress effects by inhibiting cortical neuron excitation. Both L-theanine and caffeine, which green tea contains, have been highlighted for their beneficial effects on cognition and mood. Methods In this study, we investigated the effects of orally administered L-theanine or caffeine on mental ta...

  13. Graphene platforms for the detection of caffeine in real samples

    Energy Technology Data Exchange (ETDEWEB)

    Khoo, Weslie Yu Heng; Pumera, Martin; Bonanni, Alessandra, E-mail: a.bonanni@ntu.edu.sg

    2013-12-04

    Graphical abstract: -- Highlights: •Commercial caffeine was detected on different chemically modified graphenes. •Electrochemically reduced graphene (ERGO) provided the best performance. •ERGO was then employed for the detection of caffeine in real samples. -- Abstract: The analysis of food components is of high importance due to food safety and security. Here the electrochemical detection of caffeine was performed on different chemically modified graphene (CMG) surfaces carrying diverse amount of defects and oxygen functionalities. The analytical performances of graphite oxide (GPO), graphene oxide (GO), and electrochemically reduced graphene oxide (ERGO) were compared for the first time for the detection of caffeine. It was found that ERGO showed the most favourable analytical parameters, such as lower oxidation potential, sensitivity, linearity and reproducibility of the response. ERGO was then used for the analysis of real samples. Caffeine levels of soluble coffee, teas and energetic drinks were measured without the need of any sample pre-treatment. Our findings are very important to gain more insight into the applicability of different graphene materials to real samples for sense-and-act analysis.

  14. Catechins decrease neurological severity score through apoptosis and neurotropic factor pathway in rat traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Retty Ratnawati

    2017-08-01

    Administration of catechins decreased NSS through inhibiting inflammation and apoptosis, as well as induced the neurotrophic factors in rat brain injury. Catechins may serve as a potential intervention for TBI.

  15. Alleviation of UV-B stress in Arabidopsis using tea catechins

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... Kit (Biobasic Inc., Canada) following the manufacturers instructions. Approximately 3 µg total RNA and 0.5 µg oligo-pd(T)18 were used in a 20 µl reaction volume. The reverse transcription was carried out with 20 units of Maloney Murine Leukemia Virus (MML-V) reverse transcriptase for 1 h and the reaction ...

  16. Intake of Japanese and Chinese teas reduces risk of Parkinson's disease.

    Science.gov (United States)

    Tanaka, Keiko; Miyake, Yoshihiro; Fukushima, Wakaba; Sasaki, Satoshi; Kiyohara, Chikako; Tsuboi, Yoshio; Yamada, Tatsuo; Oeda, Tomoko; Miki, Takami; Kawamura, Nobutoshi; Sakae, Nobutaka; Fukuyama, Hidenao; Hirota, Yoshio; Nagai, Masaki

    2011-07-01

    Studies that have addressed the association between the intake of coffee or caffeine and Parkinson's disease (PD) were conducted mainly in Western countries. Little is known about this relationship in an Asian population. Therefore, we performed an assessment of the association of the intake of coffee, other caffeine-containing beverages, and caffeine with the risk of PD in Japan. The study involved 249 PD cases and 368 control subjects. Information on dietary factors was obtained through a self-administered diet history questionnaire. Adjustment was made for sex, age, region of residence, educational level, pack-years of smoking, body mass index, the dietary glycemic index, and intake of cholesterol, vitamin E, β-carotene, vitamin B(6,) alcohol, and iron. Intake of coffee, black tea, and Japanese and Chinese teas was significantly inversely associated with the risk of PD: the adjusted odds ratios in comparison of the highest with the lowest quartile were 0.52, 0.58, and 0.59, respectively (95% confidence intervals = 0.30-0.90, 0.35-0.97, and 0.35-0.995, respectively). A clear inverse dose-response relationship between total caffeine intake and PD risk was observed. We confirmed that the intake of coffee and caffeine reduced the risk of PD. Furthermore, this is the first study to show a significant inverse relationship between the intake of Japanese and Chinese teas and the risk of PD. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Enhanced uptake and transport of (+)-catechin and (−)-epigallocatechin gallate in niosomal formulation by human intestinal Caco-2 cells

    Science.gov (United States)

    Song, Qinxin; Li, Danhui; Zhou, Yongzhi; Yang, Jie; Yang, Wanqi; Zhou, Guohua; Wen, Jingyuan

    2014-01-01

    The aim of this study was to evaluate (+)-catechin and (−)-epigallocatechin gallate (EGCG) cellular uptake and transport across human intestinal Caco-2 cell monolayer in both the absence and presence of niosomal carrier in variable conditions. The effect of free drugs and drug-loaded niosomes on the growth of Caco-2 cells was studied. The effects of time, temperature, and concentration on drug cellular uptake in the absence or presence of its niosomal delivery systems were investigated. The intestinal epithelial membrane transport of the drug-loaded niosomes was examined using the monolayer of the human Caco-2 cells. The kinetics of transport, and the effect of temperature, adenosine triphosphate inhibitor, permeability glycoprotein inhibitor, multidrug resistance-associated protein 2 inhibitor, and the absorption enhancer on transport mechanism were investigated. It was found that the uptake of catechin, EGCG, and their niosomes by Caco-2 cells was 1.22±0.16, 0.90±0.14, 3.25±0.37, and 1.92±0.22 μg/mg protein, respectively (n=3). The apparent permeability coefficient values of catechin, EGCG, and their niosomes were 1.68±0.16, 0.88±0.09, 2.39±0.31, and 1.42±0.24 cm/second (n=3) at 37°C, respectively. The transport was temperature- and energy-dependent. The inhibitors of permeability glycoprotein and multidrug resistance-associated protein 2 and the absorption enhancer significantly enhanced the uptake amount. Compared with the free drugs, niosomal formulation significantly enhanced drug absorption. Additionally, drug-loaded niosomes exhibited stronger stability and lower toxicity. These findings showed that the oral absorption of tea flavonoids could be improved by using the novel drug delivery systems. PMID:24855353

  18. Caffeine as a Gelator

    Directory of Open Access Journals (Sweden)

    Nonappa

    2016-03-01

    Full Text Available Caffeine (a stimulant and ethanol (a depressant may have opposite effects in our body, but under in vitro conditions they can “gel” together. Caffeine, being one of the widely used stimulants, continued to surprise the scientific community with its unprecedented biological, medicinal and physicochemical properties. Here, we disclose the supramolecular self-assembly of anhydrous caffeine in a series of alcoholic and aromatic solvents, rendering a highly entangled microcrystalline network facilitating the encapsulation of the solvents as illustrated using direct imaging, microscopy analysis and NMR studies.

  19. An Appraisal of Drug-Drug Interactions with Green Tea (Camellia sinensis).

    Science.gov (United States)

    Albassam, Ahmed A; Markowitz, John S

    2017-04-01

    This review summarizes published in vitro , animal, and clinical studies investigating the effects of green tea ( Camellia sinensis ) extract and associated catechins on drug-metabolizing enzymes and drug transporters. In vitro studies suggest that green tea extract and its main catechin, (-)-epigallocatechin-3-gallate, to varying degrees, inhibit the activity of CYP1A1, CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2D6, and CYP3A4. UGT1A1 and UGT1A4 isoforms were also inhibited by (-)-epigallocatechin-3-gallate. Animal studies suggest green tea extract and/or (-)-epigallocatechin-3-gallate significantly increase the bioavailability of diltazem, verapamil, tamoxifen simvastatin, 5-fluorouracil, and nicardipine. Conversely, green tea extract and/or (-)-epigallocatechin-3-gallate reduce the bioavailability of quetiapine, sunitinib, clozapine, and nadolol. Of the few clinical studies available for review, it appears neither green tea extract nor (-)-epigallocatechin-3-gallate inhibit any major cytochrome P450 enzyme. Regarding drug transporters, in vitro studies indicate P-glycoprotein, organic anion transporting polypeptide 1A1, organic anion transporting polypeptide 1B1, organic anion transporting polypeptide 1B3, organic anion transporting polypeptide 2B1, organic cation transporter 1, organic cation transporter 2, multidrug and toxin extrusion 1, and multidrug and toxin extrusion 2-K are potentially inhibited by green tea extract. A clinical study indicates the organic anion transporting polypeptide 1A1 transporter is inhibited by (-)-epigallocatechin-3-gallate while P-glycoprotein is unaffected. In conclusion, the ingestion of green tea extract or its associated catechins is not expected to result in clinically significant influences on major cytochrome P450 or uridine 5'-diphospho-glucuronosyltransferase enzyme substrates or drugs serving as substrates of P-glycoprotein. However, some caution is advised in the consumption of significant amounts of green tea beverages or

  20. A synergistic effect of GABA tea and copper(II) on DNA breakage in human peripheral lymphocytes.

    Science.gov (United States)

    Wang, Hsueh-Fang; Chuang, Show-Mei; Hsiao, Ching-Chuan; Cherng, Shur-Hueih

    2011-04-01

    GABA tea is a tea product that contains a high level of γ-aminobutyric acid (GABA). The oxidant and antioxidant roles of GABA tea in DNA damage were investigated in this study. DNA cleavage was observed by GABA-tea extract in the presence of copper ions. Comet assay revealed that combination of GABA-tea extract, but not pure GABA, and Cu(2+) is capable of oxidatively degrading cellular DNA in human peripheral lymphocytes. Using various reactive oxygen scavengers, we found that catalase and sodium azide effectively inhibited GABA-tea extract/Cu(II)-induced DNA degradation, suggesting the essential role of singlet oxygen and H(2)O(2) in the reaction. In addition, neocuproine inhibited the DNA degradation, confirming that Cu(I) is an intermediate in the DNA cleavage reaction. Therefore, we speculate that GABA-tea extract/Cu(II)-induced DNA damage is probably mediated through the formation of H(2)O(2) and the reduction of copper. Furthermore, our data showed that GABA-tea extract was more genotoxic and pro-oxidant than its major catechin constituent, (-)-epigallocatechin-3-gallate (EGCG), leading to DNA cleavage in the presence of Cu(2+). These findings will provide implications for the potential of GABA-tea extract in anticancer property, which may involve copper ions and the consequent pro-oxidant action. Copyright © 2010 Elsevier Ltd. All rights reserved.

  1. Persistence of thiacloprid and deltamethrin residues in tea grown at different locations of North-East India.

    Science.gov (United States)

    Sharma, Nitesh; Banerjee, Hemanta; Pal, Srikumar; Sharma, K K

    2018-07-01

    In order to examine the residues of thiacloprid (90 and 180 g a.i./ha) and deltamethrin (10 and 20 g a.i./ha) in fresh tea leaves, made tea and tea infusion, field experiments were conducted at three different locations viz. Kamalpur tea estate, Darjeeling; West Bengal, Teok tea Estate and AAU, Jorhat; Assam in India. Regardless of location and doses, residues of both the insecticides dissipated following first order kinetics. The half-life of Thiacloprid (4.93-5.38 days) was longer than that of deltamethrin (1.78-1.94 days). Processing of green tea leaves reduced the residue level of thiacloprid and deltamethrin in made tea. No residues of both these insecticides could be detected in tea infusion. With respect to the phenolic distribution in tea, a marked increase in total catechin monomers with thiacloprid and greater accumulation of EGCG and ECG (indices of phenol quality) with deltamethrin were observed. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Strontium-90 and cesium-137 in tea (Japanese tea)

    International Nuclear Information System (INIS)

    1982-01-01

    Strontium-90 and cesium-137 in tea (Japanese tea) were determined. Five hundred grams of manufactured green tea was collected from six sampling locations in Japan. The results are shown in a table. (Namekawa, K.)

  3. Green tea and coffee consumption is inversely associated with depressive symptoms in a Japanese working population.

    Science.gov (United States)

    Pham, Ngoc Minh; Nanri, Akiko; Kurotani, Kayo; Kuwahara, Keisuke; Kume, Ayami; Sato, Masao; Hayabuchi, Hitomi; Mizoue, Tetsuya

    2014-03-01

    To examine the association between the consumption of green tea, coffee and caffeine and depressive symptoms. Cross-sectional study. Consumption of green tea and coffee was ascertained with a validated dietary questionnaire and the amount of caffeine intake was estimated from these beverages. Depressive symptoms were measured using the Center for Epidemiologic Studies Depression Scale. Multiple logistic regression analysis was performed to compute odds ratios and 95% confidence intervals for depressive symptoms with adjustments for potential confounders. Two workplaces in north-eastern Kyushu, Japan, in 2009. A total of 537 men and women aged 20-68 years. Higher green tea consumption was associated with a lower prevalence of depressive symptoms. Compared with participants consuming ≤1 cup/d, those consuming ≥4 cups green tea/d had a 51% significantly lower prevalence odds of having depressive symptoms after adjustment for potential confounders, with significant trend association (P for trend = 0·01). Further adjustment for serum folate slightly attenuated the association. Coffee consumption was also inversely associated with depressive symptoms (≥2 cups/d v. green tea, coffee and caffeine may confer protection against depression.

  4. Aged leaves effect on essential components in green and oolong tea

    Directory of Open Access Journals (Sweden)

    M.M. Rahman

    2013-12-01

    Full Text Available Tea leaf encompasses essential components like caffeine, polyphenol, lipid etc. The study was conducted to find out the essential constituents in green and oolong tea from aged tea leaves during the year of 2012. Tea leaves with different plucked aged were collected from Lackatoorah Tea Estate at sylhet district in Bangladesh. Collected leaves were processesed to make desirable samples for biochemical analysis in the laboratory of Department of Food Enginnering and Tea Technology, SUST. Results revealed that the essential constituents like moisture, caffeine, polyphenol, lipid, protein, ash, ascorbic acid, acidity and pH value in green tea made from different aged leaves were found slightly higher than oolong tea, ranged from 6.38±1.06 to 3.49±0.59%; 4.91±0.82 to 1.49±0.24%; 30.88±5.15 to 18.23±3.04%; 7.50±1.25 to 9.58±1.59%; 13.15±2.19 to 17.33±2.88%; 3.87±1.65 to 7.86±1.31%; 48.4±8.05 to 21.3±3.55(mg; 2.13±0.68 to 1.18±0.19% and 5.52±0.11 to 5.97±0.18%, respectively. Similarly, the moisture, caffeine, polyphenol, lipid, protein, ash, ascorbic acid, acidity and pH value from different aged leaves were found in oolong tea from 6.19±1.04 to 2.98±0.49%; 4.68±0.78 to 1.11±0.19%; 20.89±3.48 to 8.23±1.37%; 6.40±1.07 to 9.13±1.52%; 13.03±2.17 to 17.19±2.86%; 3.44±0.58 to 7.57±1.27% 6.44±1.08 to 0.98±0.17 (mg; 2.02±0.34to 1.02±0.17% and 5.53±0.11 to 5.97±0.20%, respectively. Therefore, young tea leaves (i.e. 5 to 8 days tea leaves should be plucked for considering useful constituents in processed green tea and oolong tea.

  5. Qualitative and quantitative analysis of catechin and quercetin in ...

    African Journals Online (AJOL)

    Purpose: To perform a qualitative and quantitative analysis of catechin and quercetin in flavonoids extracted from Rosa roxburghii Tratt. Methods: Total flavonoids were determined using ultraviolet spectrophotometry (UV) at 500 nm. The optimal gradient program started with 15 % methanol and was kept within a period of 0 ...

  6. Catechin content and consumption ratio of the collared lemming

    DEFF Research Database (Denmark)

    Berg, Thomas B.

    2003-01-01

    catechin content. Dicrostonyx species are known to have specialised on shrubs, especially Dryas spp. and Salix spp., rather than graminoids like other related microtines. Bioassays were conducted using food material from Dryas spp., Salix arctica, Vaccinium uliginosum, Kobresia myosuroides and Poa glauca...

  7. Catechin-3-0-rhamoside chain procyanidins from mangrove bark

    Science.gov (United States)

    Suminar Achmadi; Gustini Syahbirin; Elvin T. Chonng; Richard W. Hemingway

    1994-01-01

    Acid-catalysed cleavage of 'purified' condensed tannin isolates from Bruguiera gymnorrhiza (tancang) bark in the presence of phloroglucinol as a capture nucleophile gave, in addition to the expected procyanidin- and prodelphinidin-phloroglucinol adducts, 3-O-α-L-rhamnopyranosyl-(+)-catechin-(4α...

  8. Phytochemical profiles and antioxidant activity of 27 cultivars of tea.

    Science.gov (United States)

    Zeng, Liang; Luo, Liyong; Li, Hongjun; Liu, Ruihai

    2017-08-01

    Tea, rich in phytochemicals, has been suggested to have human health benefits. The phenolic profiles, antioxidant and antiproliferative activities of 27 tea cultivars were determined. Wide ranges of variation were found in analyzed cultivars for the contents of water-soluble phenolics (121.6-223.7 mg/g dry weight (DW)), total catechins (TC) (90.5-177.2 mg/g DW), antioxidant activities (PSC values 627.3-2332.3 μmol of vitamin C equiv/g DW, ORAC values (1865.1-3489.3 μmol of vitamin C equiv/g DW), CAA values (37.7-134.3 μmol of QE/g DW without PBS wash and 25.3-75.4 μmol of QE/g DW with PBS wash) and antiproliferative activity (53.0-90.8% at the concentration of 400 μg/mL extracts). The PSC, ORAC and CAA values were significantly correlated with phenolics, epicatechin gallate (ECG), CC and TC. Knowledge of specific differences among tea cultivars is important for breeding tea cultivars and gives sights to its potential application to promote health.

  9. The Czech Tea Profession and the Phenomenon of Tea Rooms

    OpenAIRE

    Schröderová, Karolína

    2015-01-01

    In this bachelor thesis I have focused on the Czech tea culture and tea profession across tea rooms. I have dealt with influences that led to the present tea rooms' appearances. Furthermore I am dealing with ways of tea culture spreading, and what conduces to the tea room establishing. I am using the term of subculture in the connection with the tea culture, its meaning and position in the Czech culture. The main data source were semi- structured interviews with the tea rooms owners, all comp...

  10. Phenolic compounds in cultures of tissues of tea plants and the effect of light on their synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Koretskaya, T.F.; Zaprometov, M.N.

    1975-01-01

    Stem and leaf calluses of tea plants (Camellia sinensis) retain the capacity for synthesis of phenolic compounds. The content of phenolic compounds comprises 2 to 5 percent of dry weight, the main share (80 to 95 percent) belonging to catechins and leucoanthocyans, including their polymeric forms. The following compounds were detected in callus tissue: (--)-epicatechin, (+)-catechin, two leucoanthocyans, and several unidentified phenolic compounds that fluoresce in UV. (--)-Epicatechin is predominant. In contrast to tissues of an intact plant, the callus does not contain gallocatechins or free gallic acid under the given cultivation conditions. The content of phenolic compounds changes in proportion to callus growth, their greatest amount being formed during the phase of intensive growth. Light stimulates synthesis of phenolic compounds, including the most reduced group of flavonoids, viz., leucoanthocyans and catechins.

  11. A comparative study of the antioxidant scavenging activity of green tea, black tea and coffee extracts: a kinetic approach.

    Science.gov (United States)

    Anissi, Jaouad; El Hassouni, Mohammed; Ouardaoui, Abdelkrim; Sendide, Khalid

    2014-05-01

    The antioxidant activities of three beverages, coffee, black tea and green tea, along with their major components, were investigated in terms of their reaction with the stable radical 2,2'-diphenyl-2-picrylhydrazyl (DPPH). We used a kinetic approach in parallel with quantification methods based on a fixed end-point to determine the scavenging efficiency of compounds abundant in these beverages during their reaction with DPPH using a stopped-flow spectrophotometer-based method. Ascorbic acid, (+)-catechin, (-)-epigallocatechin, tannic acid, and caffeic acid were selected as model antioxidants to study in coffee, black tea and green tea. We applied a second-order model to demonstrate similarities in the kinetics behavior of beverages and related compounds. Our findings showed the slopes k2(')((mol/L)(-1)s(-1)) and k2max(')((mol/L)(1)s(-1)) exhibited similar and correlated values; we suggest the variation in k2(') as a function of time is more informative about antioxidant properties than reaction with DPPH alone. We also used IC100 to test the reliability of the relative stoichiometry using a new comparative parameter "n", which was calculated as: n=c0DPPHIC100 (mol/L(mol/L)(-1), (mol/L)mlmg(-1) or molg(-1)). Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Caffeine and cardiovascular health.

    Science.gov (United States)

    Turnbull, Duncan; Rodricks, Joseph V; Mariano, Gregory F; Chowdhury, Farah

    2017-10-01

    This report evaluates the scientific literature on caffeine with respect to potential cardiovascular outcomes, specifically relative risks of total cardiovascular disease (CVD), coronary heart disease (CHD) and acute myocardial infarction (AMI), effects on arrhythmia, heart failure, sudden cardiac arrest, stroke, blood pressure, hypertension, and other biomarkers of effect, including heart rate, cerebral blood flow, cardiac output, plasma homocysteine levels, serum cholesterol levels, electrocardiogram (EKG) parameters, heart rate variability, endothelial/platelet function and plasma/urine catecholamine levels. Caffeine intake has been associated with a range of reversible and transient physiological effects broadly and cardiovascular effects specifically. This report attempts to understand where the delineations exist in caffeine intake and corresponding cardiovascular effects among various subpopulations. The available literature suggests that cardiovascular effects experienced by caffeine consumers at levels up to 600 mg/day are in most cases mild, transient, and reversible, with no lasting adverse effect. The point at which caffeine intake may cause harm to the cardiovascular system is not readily identifiable in part because data on the effects of daily intakes greater than 600 mg is limited. However, the evidence considered within this review suggests that typical moderate caffeine intake is not associated with increased risks of total cardiovascular disease; arrhythmia; heart failure; blood pressure changes among regular coffee drinkers; or hypertension in baseline populations. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  13. L-theanine and caffeine improve task switching but not intersensory attention or subjective alertness.

    Science.gov (United States)

    Einöther, Suzanne J L; Martens, Vanessa E G; Rycroft, Jane A; De Bruin, Eveline A

    2010-04-01

    Tea ingredients L-theanine and caffeine have repeatedly been shown to deliver unique cognitive benefits when consumed in combination. The current randomized, placebo-controlled, double-blind, cross-over study compared a combination of L-theanine (97 mg) and caffeine (40 mg) to a placebo on two attention tasks and a self-report questionnaire before, and 10 and 60 min after consumption. The combination of L-theanine and caffeine significantly improved attention on a switch task as compared to the placebo, while subjective alertness and intersensory attention were not improved significantly. The results support previous evidence that L-theanine and caffeine in combination can improve attention. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Fast gradient HPLC/MS separation of phenolics in green tea to monitor their degradation.

    Science.gov (United States)

    Šilarová, Petra; Česlová, Lenka; Meloun, Milan

    2017-12-15

    The degradation of catechins and other phenolics in green tea infusions were monitored using fast HPLC/MS separation. The final separation was performed within 2.5min using Ascentis Express C18 column (50mm×2.1mm i.d.) packed with 2μm porous shell particles. Degradation was studied in relation to the temperature of water (70, 80, 90°C) and the standing time of the infusion (up to 6h). Along with chromatographic separation, the antioxidant properties of the infusions were monitored using two spectrophotometric methods. During staying of green tea infusion, the degradation of some catechins probably to gallic acid was observed. Finally, the influence of tea bag storage on antioxidant properties of green tea was evaluated. Rapid degradation of antioxidants after 3weeks was observed. The principal component analysis, factor analysis and discriminant analysis were used for the statistical evaluation of obtained experimental data. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study.

    Science.gov (United States)

    Zokti, James A; Sham Baharin, Badlishah; Mohammed, Abdulkarim Sabo; Abas, Faridah

    2016-07-26

    Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE). To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD), gum arabic (GA) and chitosan (CTS) and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%-88.04%, 19.32-24.90 (g GAE/100 g), and 29.52%-38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%-5.11%, 0.28-0.36, 3.22%-4.71%, 0.22-0.28 g/cm³ and 40.43-225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF) and simulated intestinal fluid (SIF) was determined as 142.00%-188.63% and 207.55%-231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC) and antioxidant activity did not decrease significantly (p ≥ 0.05) under 4 °C storage conditions. The half-life study results were in the range of 35-60, 34-65 and 231-288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

  16. Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study

    Directory of Open Access Journals (Sweden)

    James A. Zokti

    2016-07-01

    Full Text Available Green tea polyphenols have been reported to possess many biological properties. Despite the many potential benefits of green tea extracts, their sensitivity to high temperature, pH and oxygen is a major disadvantage hindering their effective utilization in the food industry. Green tea leaves from the Cameron Highlands Malaysia were extracted using supercritical fluid extraction (SFE. To improve the stability, green tea extracts were encapsulated by spray-drying using different carrier materials including maltodextrin (MD, gum arabic (GA and chitosan (CTS and their combinations at different ratios. Encapsulation efficiency, total phenolic content and antioxidant capacity were determined and were found to be in the range of 71.41%–88.04%, 19.32–24.90 (g GAE/100 g, and 29.52%–38.05% respectively. Further analysis of moisture content, water activity, hygroscopicity, bulk density and mean particles size distribution of the microparticles were carried out and the results ranged from; 2.31%–5.11%, 0.28–0.36, 3.22%–4.71%, 0.22–0.28 g/cm3 and 40.43–225.64 µm respectively. The ability of the microparticles to swell in simulated gastric fluid (SGF and simulated intestinal fluid (SIF was determined as 142.00%–188.63% and 207.55%–231.77%, respectively. Release of catechin polyphenol from microparticles in SIF was higher comparable to that of SGF. Storage stability of encapsulated catechin extracts under different temperature conditions was remarkably improved compared to non-encapsulated extract powder. This study showed that total catechin, total phenolic content (TPC and antioxidant activity did not decrease significantly (p ≥ 0.05 under 4 °C storage conditions. The half-life study results were in the range of 35–60, 34–65 and 231–288 weeks at storage temperatures of 40 °C, 25 °C and 4 °C respectively, therefore, for improved shelf-life stability we recommend that microparticles should be stored at temperatures below 25 °C.

  17. New insights into the mechanisms of polyphenols beyond antioxidant properties; lessons from the green tea polyphenol, epigallocatechin 3-gallate.

    Science.gov (United States)

    Kim, Hae-Suk; Quon, Michael J; Kim, Jeong-A

    2014-01-01

    Green tea is rich in polyphenol flavonoids including catechins. Epigallocatechin 3-gallate (EGCG) is the most abundant and potent green tea catechin. EGCG has been extensively studied for its beneficial health effects as a nutriceutical agent. Based upon its chemical structure, EGCG is often classified as an antioxidant. However, treatment of cells with EGCG results in production of hydrogen peroxide and hydroxyl radicals in the presence of Fe (III). Thus, EGCG functions as a pro-oxidant in some cellular contexts. Recent investigations have revealed many other direct actions of EGCG that are independent from anti-oxidative mechanisms. In this review, we discuss these novel molecular mechanisms of action for EGCG. In particular, EGCG directly interacts with proteins and phospholipids in the plasma membrane and regulates signal transduction pathways, transcription factors, DNA methylation, mitochondrial function, and autophagy to exert many of its beneficial biological actions.

  18. (+)-Catechin inhibition of transmissible gastroenteritis coronavirus in swine testicular cells is involved its antioxidation.

    Science.gov (United States)

    Liang, Wulong; He, Lei; Ning, Pengbo; Lin, Jihui; Li, Helin; Lin, Zhi; Kang, Kai; Zhang, Yanming

    2015-12-01

    Transmissible gastroenteritis virus (TGEV) causes transmissible gastroenteritis (TGE), especially in newborn piglets, which severely threatens the worldwide pig industry. In this study, (+)-catechin was evaluated for its antiviral effect against TGEV in vitro. Viability assays revealed that (+)-catechin treatment exerted a dose-dependent rescue effect in TGEV-infected ST cells, and this result was only obtained with the post-treatment application of (+)-catechin. The viral yields in (+)-catechin-treated cultures were reduced by almost three log10 units. Quantitative real-time PCR analysis of the TGEV genome revealed that TGEV RNA replication was restricted after (+)-catechin treatment. Intracellular reactive oxygen species (ROS) detection showed that (+)-catechin alleviated ROS conditions induced by TGEV infection. Our results showed that (+)-catechin exerts an inhibitory effect on TGEV proliferation in vitro and is involved its antioxidation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Metabolic and physiological effects of ingesting extracts of bitter orange, green tea and guarana at rest and during treadmill walking in overweight males.

    Science.gov (United States)

    Sale, C; Harris, R C; Delves, S; Corbett, J

    2006-05-01

    This study examined the acute effects of ingesting a widely used commercial formula containing extracts of bitter orange, green tea and guarana (Gx) on the metabolic rate and substrate utilisation in overweight, adult males at rest (study 1) and during treadmill walking (study 2). Two different groups of 10 sedentary males with more than 20% body fat participated in studies 1 and 2. In each study, subjects participated in two experimental trials during which they were given two 500 mg capsules containing either Gx or a placebo (P) in a counterbalanced double-blind manner. Doses of the main active ingredients were 6 mg of synephrine, 150 mg caffeine and 150 mg catechin polyphenols. In study 1, subjects completed 7 h supine rest with baseline measures taken during the first hour, with expired gases, blood pressure, heart rate and venous blood being collected every 30 min for the remaining 6 h following ingestion of Gx or P. In study 2, subjects exercised for 60 min at 60% heart rate reserve following ingestion of Gx or P 1 h previously. Venous blood samples were collected twice at rest and at 5, 10, 15, 20, 30, 40, 50 and 60 min, with expired gas measurements taken at 4, 9, 14, 19, 29, 39, 49 and 59 min. In both studies, venous blood was analysed for NEFA, glycerol, glucose and lactate concentrations, while expired gases were used to calculate ATP production from carbohydrate and NEFA, as well as the total substrate utilised. The results did not show any significant effect of Gx ingestion on total ATP utilisation during 6 h rest or during 60 min treadmill walking. Changes were observed in the relative contributions of CHO and NEFA oxidation to ATP production in both studies, such that there was an increase in ATP production from CHO and a decrease from NEFA. The increase in CHO oxidation was shown to be as high as 30% at rest.

  20. Effect of the caffeine on treated and non-treated plasmid DNA with stannic chloride; Efeito da cafeina em DNA plasmidial tratado e nao tratado com cloreto estanoso

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Silvana Ramos F. [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]|[Universidade Federal Fluminense, Niteroi, RJ (Brazil). Faculdade de Ciencias Medicas. Curso de Pos-graduacao em Patologia Experimental; Mattos, Jose C.P. de; Dantas, Flavio; Araujo, Adriano Caldeira de; Bernardo-Filho, Mario [Universidade do Estado, Rio de Janeiro, RJ (Brazil). Inst. de Biologia. Dept. de Biofisica e Biometria]. E-mail: bernardo@uerj.br

    2000-07-01

    Caffeine, a methilxantine drug is a component of coffee, tea, stimulants and other drinks. Caffeine inhibits phosphodiesterase leading to intracellular accumulation of cyclic AMP, blocks adenosine receptors, and increases the release of Ca{sup 2+}. We have studied the possible effect of caffeine in DNA plasmid treated or not with stannous chloride (SnCl{sub 2}). Previous evaluations of the effect of caffeine on the labeling of red blood cells and plasma proteins with technetium-99m have showed a decrease of % ATI in the insoluble fraction of plasma proteins. Samples of DNA were treated with SnCl{sub 2} (0 and 200{mu}g/ml) in 0.8% agarose. SnCl{sub 2} has induced break on DNA and caffeine has not showed effect on the DNA. This indicates that caffeine does not eliminate the oxidant action of SnCl{sub 2} and does not promote break in isolated DNA plasmid. (author)

  1. Implications of Green Tea and Its Constituents in the Prevention of Cancer via the Modulation of Cell Signalling Pathway

    Science.gov (United States)

    Rahmani, Arshad H.; Al shabrmi, Fahad M.; Allemailem, Khaled S.; Aly, Salah M.; Khan, Masood A.

    2015-01-01

    Green tea is commonly used as a beverage worldwide, especially in China, Japan, Morocco, and Saudi Arabia. Green tea and its constituents have been considered very effective in the prevention and treatment of various diseases. It contains a variety of catechins, which show a pivotal role in the modulation of biological activities and also act as chemopreventive agents. Earlier studies have confirmed that green tea and its chief constituent epigallocatechin gallate (EGCG) have a potential role in the management of cancer through the modulation of cell signaling pathways. In this review, we focused on the beneficial effects of green tea and its constituents in the cancer prevention and treatment and its impact on modulation of molecular pathways. PMID:25977926

  2. Anti-cancer properties epigallocatechin-gallate contained in green tea 

    Directory of Open Access Journals (Sweden)

    Magdalena Donejko

    2013-01-01

    Full Text Available Numerous in vivo and in vitro studies point to the possibility of using green tea’s catechins in chemoprevention of cancer. Recent studies show the inhibitory effects of epigallocatechin gallate on the growth of existing tumors including breast cancer, skin cancer and gastrointestinal tract cancers. Another mode of action of biologically active compounds in green tea involves inhibiting the neoplastic process.All these mechanisms may be useful in prevention and inhibition of the cancer processes (initiation, promotion and progress by the consumption of green tea. However, clinical studies show contradictory results. Several independent factors, such as the temperature of the beverage, the duration of consumption, the amount of consumed tea and the diet used by the analyzed group, have a decisive effect on the final effect of plant polyphenols on the process of carcinogenesis. 

  3. Functional Characterization of Epitheaflagallin 3-O-Gallate Generated in Laccase-Treated Green Tea Extracts in the Presence of Gallic Acid.

    Science.gov (United States)

    Itoh, Nobuya; Kurokawa, Junji; Isogai, Yasuhiro; Ogasawara, Masaru; Matsunaga, Takayuki; Okubo, Tsutomu; Katsube, Yuji

    2017-12-06

    Epitheaflagallin (ETFG) and epitheaflagallin 3-O-gallate (ETFGg) are minor polyphenols in black tea extract that are enzymatically synthesized from epigallocatechin (EGC) and epigallocatechin gallate (EGCg), respectively, in green tea extract via laccase oxidation in the presence of gallic acid. The constituents of laccase-treated green tea extract in the presence of gallic acid are thus quite different from those of nonlaccase-treated green tea extract: EGC and EGCg are present in lower concentrations, and ETFG and ETFGg are present in higher concentrations. Additionally, laccase-treated green tea extract contains further polymerized catechin derivatives, comparable with naturally fermented teas such as oolong tea and black tea. We found that ETFGg and laccase-treated green tea extracts exhibit versatile physiological functions in vivo and in vitro, including antioxidative activity, pancreatic lipase inhibition, Streptococcus sorbinus glycosyltransferase inhibition, and an inhibiting effect on the activity of matrix metalloprotease-1 and -3 and their synthesis by human gingival fibroblasts. We confirmed that these inhibitory effects of ETFGg in vitro match well with the results obtained by docking simulations of the compounds with their target enzymes or noncatalytic protein. Thus, ETFGg and laccase-treated green tea extracts containing ETFGg are promising functional food materials with potential antiobesity and antiperiodontal disease activities.

  4. Assessment of the Drug-Drug Interaction Potential Between Theacrine and Caffeine in Humans.

    Science.gov (United States)

    He, Hui; Ma, Dejian; Crone, Laura Brooks; Butawan, Matthew; Meibohm, Bernd; Bloomer, Richard J; Yates, Charles R

    2017-09-01

    Objective: Theacrine, a methylurate class purine alkaloid, triggers diverse pharmacologic responses, including psychostimulatory activity by modulation of adenosinergic and dopaminergic pathways. In a double-blind, placebo-controlled study, theacrine increased energy, concentration, and mood, while reducing fatigue. Because caffeine, a methylxanthine purine alkaloid, is frequently coadministered with theacrine, we sought to determine if a pharmacokinetic and/or pharmacodynamic interaction existed between theacrine and caffeine. Methods: Eight healthy adults received theacrine, as TeaCrine ® (25 or 125 mg), caffeine (150 mg), or a combination of theacrine (125 mg) and caffeine (150 mg) in a randomized, double-blind crossover study. Blood samples were collected over a 24-hour period and analyzed by Liquid chromatrography-mass spectrometry/mass spectrometry (LC-MS/MS) for theacrine, caffeine, and paraxanthine. Pharmacodynamic response markers, heart rate and blood pressure, were recorded. Results: Theacrine pharmacokinetics was similar following administration of theacrine alone. Caffeine coadministration increased maximum plasma concentration and area under the curve of theacrine without altering theacrine half-life. Theacrine had no impact on caffeine or paraxanthine pharmacokinetics. There was no difference between treatment groups with regard to heart rate or systolic/diastolic blood pressure. Conclusions: Coadministration of theacrine and caffeine results in a clinically significant pharmacokinetic interaction, viz ., increased theacrine exposure. Enhanced oral bioavailability is the most likely mechanism by which caffeine alters theacrine exposure. However, further studies examining the contribution of presystemic elimination mechanisms, for example, efflux transport and/or gut metabolism, to theacrine bioavailability are needed to confirm the exact mechanism(s). Hemodynamic parameters were unaltered despite the pharmacokinetic interaction, suggesting

  5. Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children

    Science.gov (United States)

    Richards, Gareth; Smith, Andrew

    2015-01-01

    Previous research suggests that effects of caffeine on behaviour are positive unless one is investigating sensitive groups or ingestion of large amounts. Children are a potentially sensitive subgroup, and especially so considering the high levels of caffeine currently found in energy drinks. The present study used data from the Cornish Academies Project to investigate associations between caffeine (both its total consumption, and that derived separately from energy drinks, cola, tea, and coffee) and single-item measures of stress, anxiety, and depression, in a large cohort of secondary school children from the South West of England. After adjusting for additional dietary, demographic, and lifestyle covariates, positive associations between total weekly caffeine intake and anxiety and depression remained significant, and the effects differed between males and females. Initially, effects were also observed in relation to caffeine consumed specifically from coffee. However, coffee was found to be the major contributor to high overall caffeine intake, providing explanation as to why effects relating to this source were also apparent. Findings from the current study increase our knowledge regarding associations between caffeine intake and stress, anxiety, and depression in secondary school children, though the cross-sectional nature of the research made it impossible to infer causality. PMID:26508718

  6. Caffeine consumption and self-assessed stress, anxiety, and depression in secondary school children.

    Science.gov (United States)

    Richards, Gareth; Smith, Andrew

    2015-12-01

    Previous research suggests that effects of caffeine on behaviour are positive unless one is investigating sensitive groups or ingestion of large amounts. Children are a potentially sensitive subgroup, and especially so considering the high levels of caffeine currently found in energy drinks. The present study used data from the Cornish Academies Project to investigate associations between caffeine (both its total consumption, and that derived separately from energy drinks, cola, tea, and coffee) and single-item measures of stress, anxiety, and depression, in a large cohort of secondary school children from the South West of England. After adjusting for additional dietary, demographic, and lifestyle covariates, positive associations between total weekly caffeine intake and anxiety and depression remained significant, and the effects differed between males and females. Initially, effects were also observed in relation to caffeine consumed specifically from coffee. However, coffee was found to be the major contributor to high overall caffeine intake, providing explanation as to why effects relating to this source were also apparent. Findings from the current study increase our knowledge regarding associations between caffeine intake and stress, anxiety, and depression in secondary school children, though the cross-sectional nature of the research made it impossible to infer causality. © The Author(s) 2015.

  7. Caffeine Content of Tea and Coffee | Kaplan | South African Medical ...

    African Journals Online (AJOL)

    South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 47, No 3 (1973) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

  8. Ad lib caffeine consumption, symptoms of caffeinism, and academic performance.

    Science.gov (United States)

    Gilliland, K; Andress, D

    1981-04-01

    The authors explored the relationship between ad lib caffeine consumption in college students and the incidence of caffeinism, characterized by heightened anxiety, depression, and various psychophysiological reactions. Students were randomly selected from four groups (abstainers from caffeine and low, moderate, and high consumers). A survey battery assessed the effects of caffeine, incidence of psychophysiological disorders, state-trait anxiety, and depression. The moderate and high consumer groups combined reported significantly higher trait anxiety and depression scores when compared with abstainers. The high consumer group also reported significantly higher levels of symptoms of caffeinism, higher frequency of psychophysiological disorders, and lower academic performance.

  9. Separation of Caffeine from Beverages and Analysis Using Thin-Layer Chromatography and Gas Chromatography-Mass Spectrometry

    Science.gov (United States)

    Torres y Torres, Janelle L.; Hiley, Shauna L.; Lorimor, Steven P.; Rhoad, Jonathan S.; Caldwell, Benjamin D.; Zweerink, Gerald L.; Ducey, Michael

    2015-01-01

    The Characterization and Analysis of a Product (CAP) project is used to introduce first-semester general chemistry students to chemical instrumentation through the analysis of caffeine-containing beverage products. Some examples of these products have included coffee, tea, and energy drinks. Students perform at least three instrumental experiments…

  10. Enrichment of Biscuits with Matcha Green Tea Powder: Its Impact on Consumer Acceptability and Acute Metabolic Response

    Directory of Open Access Journals (Sweden)

    Benjapor Phongnarisorn

    2018-02-01

    Full Text Available Matcha green tea powder (MGTP is made with finely ground green tea leaves that are rich in phytochemicals, most particularly catechins. Shortbread biscuits were enriched with MGTP and evaluated for consumer acceptability and potential functional health properties. Baking decreased the content of total catechins by 19% compared to dough, although epimerization increased the amount of (+-gallocatechin gallate at the expense of other catechins such as (−-epigallocatechin gallate. Consumer acceptability tests using a 9-point hedonic scale showed that consumers preferred enriched biscuits with low content of MGTP (2 g of MGTP 100 g−1 of flour, and an increase of sugar content did not significantly improve the acceptability of MGTP-enriched biscuits. Overall, enrichment of biscuits with MGTP did not significantly affect the postprandial glucose or triglyceride response (area under curve compared to non-enriched biscuits consumed with water or MGTP drink. Enriching biscuits with Matcha green tea is acceptable to consumers, but may not bring significant postprandial effects.

  11. Investigation of free amino acid, total phenolics, antioxidant activity and purine alkaloids to assess the health properties of non-Camellia tea

    Directory of Open Access Journals (Sweden)

    Wu Bi

    2016-03-01

    Full Text Available To find novel functional beverages from folk teas, 33 species of frequently used non-Camellia tea (plants other than Camellia were collected and compared with Camellia tea (green tea, pu-erh tea and black tea for the first time. Data are reported here on the quantities of 20 free amino acids (FAAs and three purine alkaloids (measured by UHPLC, total polyphenols (measured by Folin-Ciocalteu assay, and antioxidant activity (DPPH. The total amounts of FAAs in non-Camellia tea (0.62–18.99 mg/g are generally less than that of Camellia tea (16.55–24.99 mg/g. However, for certain FAAs, the quantities were much higher in some non-Camellia teas, such as γ-aminobutyric acid in teas from Ampelopsis grossedentata, Isodon serra and Hibiscus sabdariffa. Interestingly, theanine was detected in tea from Potentilla fruticosa (1.16±0.81 mg/g. Furthermore, the content of polyphenols in teas from A. grossedentata, Acer tataricum subsp. ginnala are significantly higher than those from Camellia tea; teas from I. serra, Pistacia chinensis and A. tataricum subsp. ginnala have remarkable antioxidant activities similar to the activities from green tea (44.23 μg/mL. Purine alkaloids (caffeine, theobromine and theophylline were not detected in non-Camellia teas. The investigation suggest some non-Camellia teas may be great functional natural products with potential for prevention of chronic diseases and aging, by providing with abundant polyphenols, antioxidants and specific FAAs.

  12. Can Tea Consumption be a Safe and Effective Therapy Against Diabetes Mellitus-Induced Neurodegeneration?

    Science.gov (United States)

    Nunes, Ana R; Alves, Marco G; Moreira, Paula I; Oliveira, Pedro F; Silva, Branca M

    2014-12-01

    Diabetes mellitus (DM) is a metabolic disease that is rapidly increasing and has become a major public health problem. Type 2 DM (T2DM) is the most common type, accounting for up to 90-95% of the new diagnosed DM cases. The brain is very susceptible to glucose fluctuations and hyperglycemia-induced oxidative stress (OS). It is well known that DM and the risk of developing neurodegenerative diseases are associated. Tea, Camellia sinensis L., is one of the most consumed beverages. It contains several phytochemicals, such as polyphenols, methylxanthines (mainly caffeine) and L-theanine that are often reported to be responsible for tea's health benefits, including in brain. Tea phytochemicals have been reported to be responsible for tea's significant antidiabetic and neuroprotective properties and antioxidant potential. Epidemiological studies have shown that regular consumption of tea has positive effects on DM-caused complications and protects the brain against oxidative damage, contributing to an improvement of the cognitive function. Among the several reported benefits of tea consumption, those related with neurodegenerative diseases are of great interest. Herein, we discuss the potential beneficial effects of tea consumption and tea phytochemicals on DM and how their action can counteract the severe brain damage induced by this disease.

  13. The effect of light and nitrogen availability on the caffeine, theophylline and allantoin contents in the leaves of Coffea arabica L.

    Directory of Open Access Journals (Sweden)

    Marcelo F. Pompelli

    2013-09-01

    Full Text Available Caffeine is the most abundant and important purine alkaloid derived from several important crop, such as coffee, tea, cocoa, guarana, and other plants. In tea and coffee plants, caffeine is predominantly produced in the young buds of leaves and in immature fruits. The effect of light-stimulating caffeine biosynthesis is uncertain, but our results clearly show that light, independent of N-availability, increases caffeine (26%, allantoin (47%, and theophylline (8% content in plants compared with those grown in a shaded (50% solar irradiation environment. Caffeine is the major low-molecular-weight nitrogenous compound in coffee plants, and at times, it functions as a chemical defense for new bud leaves. Therefore, the primary question that remains is whether caffeine can serve as a nitrogen source for other metabolic pathways. If so, plants grown under a low nitrogen concentration should promote caffeine degradation, with the consequent use of nitrogen atoms (e.g., in NH3 for the construction of other nitrogen compounds that are used for the plant’s metabolism. Our results provide strong evidence that caffeine is degraded into allantoin at low rates in N-deficient plants but not in N-enriched ones. By contrast, this degradation may represent a significant N-source in N-deficient plants.

  14. Caffeine and cognitive performance: persistent methodological challenges in caffeine research.

    Science.gov (United States)

    James, Jack E

    2014-09-01

    Human cognitive performance is widely perceived to be enhanced by caffeine at usual dietary doses. However, the evidence for and against this belief continues to be vigorously contested. Controversy has centred on caffeine withdrawal and withdrawal reversal as potential sources of experimental confounding. In response, some researchers have enlisted "caffeine-naïve" experimental participants (persons alleged to consume little or no caffeine) assuming that they are not subject to withdrawal. This mini-review examines relevant research to illustrate general methodological challenges that have been the cause of enduring confusion in caffeine research. At issue are the processes of caffeine withdrawal and withdrawal reversal, the definition of caffeine-naïve, the population representativeness of participants deemed to be caffeine-naïve, and confounding due to caffeine tolerance. Attention to these processes is necessary if premature conclusions are to be avoided, and if caffeine's complex effects and the mechanisms responsible for those effects are to be illuminated. Strategies are described for future caffeine research aimed at minimising confounding from withdrawal and withdrawal reversal. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Densitometric determination of (+)-catechin and (-)-epicatechin by 4-dimethylaminocinnamaldehyde reagent.

    Science.gov (United States)

    Glavnik, Vesna; Simonovska, Breda; Vovk, Irena

    2009-05-15

    We report the optimization of a sensitive, selective and robust derivatization method using 4-dimethylaminocinnamaldehyde (DMACA) for densitometric determination of (+)-catechin and (-)-epicatechin. The separation of these compounds was achieved by thin-layer chromatography (TLC) on cellulose plates developed with water. With DMACA in HCl, both compounds gave blue bands, while under the same conditions, vanillin produced a fast fading red coloration of bands. Quantitation at 655nm showed that for both compounds the calibration curve was linear from 2 to 12ng and polynomial from 2 to 30ng, and the repeatability of chromatography of 20ng was 3.5% (RSD, n=6). The visible limit of detection of both standards was 1ng, but the densitometric limit of detection was lower (0.2ng). The optimized DMACA reagent is superior to the more frequently used vanillin reagent and is applicable also for determination of mixtures containing other catechins ((-)-catechin, (-)-epicatechin gallate, (-)-epigallocatechin gallate, procyanidin A2, procyanidin B1 and procyanidin B2).

  16. A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood.

    Science.gov (United States)

    Dodd, F L; Kennedy, D O; Riby, L M; Haskell-Ramsay, C F

    2015-07-01

    Evidence suggests interactive effects of the tea components caffeine and L-theanine on behaviour, yet no data exists exploring the impact of the two on cerebral blood flow (CBF). The current placebo-controlled, double-blind, counterbalanced, crossover study examined the effects of caffeine and L-theanine on CBF and extended previous cognitive and mood findings by using lower doses than previous studies of a similar methodology, which more closely reflect the ratios present in tea. Twelve habitual consumers and 12 non-habitual consumers of caffeine each received 75 mg caffeine, 50 mg L-theanine, 75 mg caffeine plus 50 mg L-theanine, and placebo in a counterbalanced order across four separate visits. CBF was measured via near-infrared spectroscopy with cognition and mood assessed at baseline and 30 min post-dose. Salivary caffeine and peripheral haemodynamics were co-monitored. Caffeine reduced oxygenated haemoglobin (oxy-Hb), increased deoxygenated haemoglobin (deoxy-Hb), improved performance on attention tasks and increased overall mood ratings. Increases in deoxy-Hb following caffeine were more pronounced in non-consumers. Some evidence for increased deoxy-Hb remained when caffeine was combined with L-theanine, but this effect was attenuated and the effects of caffeine on oxy-Hb, cognition and mood were eradicated. Combining L-theanine with caffeine, at levels and ratios equivalent to one to two cups of tea, eliminated the vasoconstrictive effect and behavioural effects of caffeine. This supports previous findings of an interaction between these substances, despite a lack of effects of L-theanine in isolation. However, at the levels tested here, this did not lead to a positive impact on behaviour.

  17. Antioxidant and protective effect of inulin and catechin grafted inulin against CCl4-induced liver injury.

    Science.gov (United States)

    Liu, Jun; Lu, Jian-feng; Wen, Xiao-yuan; Kan, Juan; Jin, Chang-hai

    2015-01-01

    In this study, the antioxidant activity and hepatoprotective effect of inulin and catechin grafted inulin (catechin-g-inulin) against carbon tetrachloride (CCl4)-induced acute liver injury were investigated. Results showed that both inulin and catechin-g-inulin had moderate scavenging activity on superoxide radical, hydroxyl radical and H2O2, as well as lipid peroxidation inhibition effect. The antioxidant activity decreased in the order of Vc > catechin >catechin-g-inulin > inulin. Administration of inulin and catechin-g-inulin could significantly reduce the elevated levels of serum aspartate transaminase, alanine transaminase and alkaline phosphatase as compared to CCl4 treatment group. Moreover, inulin and catechin-g-inulin significantly increased the levels of hepatic superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glutathione and total antioxidant capacity, whereas markedly decreased the malondialdehyde level when compared with CCl4 treatment group. Notably, catechin-g-inulin showed higher hepatoprotective effect than inulin. In addition, the hepatoprotective effect of catechin-g-inulin was comparable to positive standard of silymarin. Our results suggested that catechin-g-inulin had potent antioxidant activity and potential protective effect against CCl4-induced acute liver injury. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Both phenolic and non-phenolic green tea fractionsinhibit migration of cancer cells

    Directory of Open Access Journals (Sweden)

    Ean-Jeong Seo

    2016-11-01

    Full Text Available Green tea consumption is associated with chemoprevention of many cancer types. Fresh tea leaves are rich in polyphenolic catechins, which can constitute up to 30% of the dry leaf weight. While the polyphenols of green tea have been well investigated, it is still largely unknown, whether or not non-phenolic constituents also reveal chemopreventive and anti-metastatic effects.In this study, we investigated the effects of a fraction of green tea rich in phenolic compounds (PF, a non-phenolic fraction (NPF, which contains glyceroglycolipids (GGL, and a pure glyceroglycolipid compound isolated from the non-phenolic fraction in human cancer.Dried green tea leaves were extracted and applied to a Sephadex LH-20 column. The resazurin reduction assay was used to investigate the cytotoxicity of green tea samples towards human HepG2 hepatocellular carcinoma and normal AML12 hepatocytes cells. Gene expression profiling was performed by mRNA microarray hybridization and the microarray results were validated by RT-PCR. The scratch migration assay was used to investigate the effects of green tea samples on cell migration in vitro. The changes of microtubule dynamics were observed using fluorescence microscopy.PF and NPF were prepared from methanol extract of green tea. A GGL was isolated from NPF. All three green tea samples did not show significant cytotoxic activity up to 10 µg/mL in both HepG2 and AML12 cells, whereas cytotoxicity of the control drug doxorubicin was observed with both cell lines (IC50 on AML12: 0.024 µg/mL, IC50 on HepG2: 2.103 µg/mL. We identified three sets of genes differentially expressed upon treatment with the green tea samples. The genes were associated with cytoskeleton formation, cellular movement and morphology. The correlation coefficients between mRNA expression values determined by microarray and RT-PCR were R = 0.94. HepG2 and U2OS cells treated with green tea extracts showed the delayed closures. Besides, the number of

  19. Both Phenolic and Non-phenolic Green Tea Fractions Inhibit Migration of Cancer Cells.

    Science.gov (United States)

    Seo, Ean-Jeong; Wu, Ching-Fen; Ali, Zulfiqar; Wang, Yan-Hong; Khan, Shabana I; Walker, Larry A; Khan, Ikhlas A; Efferth, Thomas

    2016-01-01

    Green tea consumption is associated with chemoprevention of many cancer types. Fresh tea leaves are rich in polyphenolic catechins, which can constitute up to 30% of the dry leaf weight. While the polyphenols of green tea have been well investigated, it is still largely unknown, whether or not non-phenolic constituents also reveal chemopreventive and anti-metastatic effects. In this study, we investigated the effects of a fraction of green tea rich in phenolic compounds (PF), a non-phenolic fraction (NPF), which contains glyceroglycolipids (GGL), and a pure glyceroglycolipid compound isolated from the non-phenolic fraction in human cancer. Dried green tea leaves were extracted and applied to a Sephadex LH-20 column. The resazurin reduction assay was used to investigate the cytotoxicity of green tea samples toward human HepG2 hepatocellular carcinoma and normal AML12 hepatocytes cells. Gene expression profiling was performed by mRNA microarray hybridization and the microarray results were validated by RT-PCR. The scratch migration assay was used to investigate the effects of green tea samples on cell migration in vitro . The changes of microtubule dynamics were observed using fluorescence microscopy. PF and NPF were prepared from methanol extract of green tea. A GGL was isolated from NPF. All three green tea samples did not show significant cytotoxic activity up to 10 μg/mL in both HepG2 and AML12 cells, whereas cytotoxicity of the control drug doxorubicin was observed with both cell lines (IC 50 on AML12: 0.024 μg/mL, IC 50 on HepG2: 2.103 μg/mL). We identified three sets of genes differentially expressed upon treatment with the green tea samples. The genes were associated with cytoskeleton formation, cellular movement, and morphology. The correlation coefficients between mRNA expression values determined by microarray and RT-PCR were R = 0.94. HepG2 and U2OS cells treated with green tea extracts showed the delayed closures. Besides, the number of distinct

  20. Quantitative Determination of Caffeine in Beverages Using a Combined SPME-GC/MS Method

    Science.gov (United States)

    Pawliszyn, Janusz; Yang, Min J.; Orton, Maureen L.

    1997-09-01

    Solid-phase microextraction (SPME) combined with gas chromatography/mass spectrometry (GC/MS) has been applied to the analysis of various caffeinated beverages. Unlike the current methods, this technique is solvent free and requires no pH adjustments. The simplicity of the SPME-GC/MS method lends itself to a good undergraduate laboratory practice. This publication describes the analytical conditions and presents the data for determination of caffeine in coffee, tea, and coke. Quantitation by isotopic dilution is also illustrated.

  1. Mothers' Consumption of Soy Drink But Not Black Tea Increases the Flavonoid Content of Term Breast Milk: A Pilot Randomized, Controlled Intervention Study.

    Science.gov (United States)

    Jochum, Frank; Alteheld, Birgit; Meinardus, Pamela; Dahlinger, Norbert; Nomayo, Antonia; Stehle, Peter

    2017-01-01

    We performed a pilot RCT to prove the hypothesis that a controlled ingestion of polyphenol-rich beverages (soy drink, decaffeinated black tea) in nutritive dosages by nursing women has an effect on the composition (flavonoid concentration, total antioxidant capacity) of breast milk. Healthy nursing women were supplemented with either 250 mL of a soy drink (12 mg isoflavones; n = 18), 300 mL decaffeinated black tea (67 mg catechins; n = 18), or 300 mL water (n = 8, control) for 6 days. Milk samples were collected before, during, and after intervention. Flavonoid content (isoflavones/catechins, HPLC) and total antioxidant capacity of milk and test drinks in milk specimens were assessed. Isoflavone content (genistein and daidzein) in breast milk increased up to 12 nmol/L after soy drink consumption; the major flavonoids constituents of black tea (catechin, epicatechin, and respective conjugates) could not be detected in milk samples. With both interventions, the total antioxidant capacity of breast milk was not affected. Mothers' daily consumption of a soy drink considerably increases isoflavone content of breast milk resulting in an estimated daily exposure of 9.6 nmol isoflavones in a 4-month-old suckling infant. Luminal flavanol uptake from black tea consumed by the nursing mother may be too low to affect flavanol concentrations in breast milk. © 2017 S. Karger AG, Basel.

  2. Condensed tannins: The formation of a diarylpropanol-catechinic acid dimer from base-catalyzed reactions of (+)-catechin

    Science.gov (United States)

    Seiji Ohara; Richard W. Hemingway

    1991-01-01

    Reaction of (+ )-catechin at pH 12 and 40 DC results in the stereoselective (if not stereospecific) formation of an enolic form of 1-[6-(3',4'-dihydroxyphenyl)-7-hydroxybicyclo[3.3.1]nonane-2,4,9-trione-3-yl]-1-(3,4-dihyroxyphenyl)-3-(2,-4,6-trihydroxyphenyl)-propan-2-ol. The n.m.r. chemical shift assignments determined by a variety of two-dimensional...

  3. Association of long-term effects of caffeine consumption on lifespan, behavior and learning performances in mature honey bees (Apis mellifere)

    OpenAIRE

    Yusaf, Marina

    2012-01-01

    Abstract Caffeine is probably the most consumed pharmacologically active substance in the world. It is found in common beverages (coffee, tea, soft drinks), in products containing cocoa or chocolate, and in medications. Honey bee (Apis mellifera) serves as an invertebrate model to understand the complexly organized brains, such as those find in mammals. Caffeine affects learning and memory in several different species, including the honey bee. The purpose of this resear...

  4. Coffee, tea and melanoma risk: findings from the European Prospective Investigation into Cancer and Nutrition.

    Science.gov (United States)

    Caini, Saverio; Masala, Giovanna; Saieva, Calogero; Kvaskoff, Marina; Savoye, Isabelle; Sacerdote, Carlotta; Hemmingsson, Oskar; Hammer Bech, Bodil; Overvad, Kim; Tjønneland, Anne; Petersen, Kristina E N; Mancini, Francesca Romana; Boutron-Ruault, Marie-Christine; Cervenka, Iris; Kaaks, Rudolf; Kühn, Tilman; Boeing, Heiner; Floegel, Anna; Trichopoulou, Antonia; Valanou, Elisavet; Kritikou, Maria; Tagliabue, Giovanna; Panico, Salvatore; Tumino, Rosario; Bueno-de-Mesquita, H B As; Peeters, Petra H; Veierød, Marit B; Ghiasvand, Reza; Lukic, Marko; Quirós, José Ramón; Chirlaque, Maria-Dolores; Ardanaz, Eva; Salamanca Fernández, Elena; Larrañaga, Nerea; Zamora-Ros, Raul; Maria Nilsson, Lena; Ljuslinder, Ingrid; Jirström, Karin; Sonestedt, Emily; Key, Timothy J; Wareham, Nick; Khaw, Kay-Tee; Gunter, Marc; Huybrechts, Inge; Murphy, Neil; Tsilidis, Konstantinos K; Weiderpass, Elisabete; Palli, Domenico

    2017-05-15

    In vitro and animal studies suggest that bioactive constituents of coffee and tea may have anticarcinogenic effects against cutaneous melanoma; however, epidemiological evidence is limited to date. We examined the relationships between coffee (total, caffeinated or decaffeinated) and tea consumption and risk of melanoma in the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a multicentre prospective study that enrolled over 500,000 participants aged 25-70 years from ten European countries in 1992-2000. Information on coffee and tea drinking was collected at baseline using validated country-specific dietary questionnaires. We used adjusted Cox proportional hazards regression models to calculate hazard ratios (HR) and 95% confidence intervals (95% CI) for the associations between coffee and tea consumption and melanoma risk. Overall, 2,712 melanoma cases were identified during a median follow-up of 14.9 years among 476,160 study participants. Consumption of caffeinated coffee was inversely associated with melanoma risk among men (HR for highest quartile of consumption vs. non-consumers 0.31, 95% CI 0.14-0.69) but not among women (HR 0.96, 95% CI 0.62-1.47). There were no statistically significant associations between consumption of decaffeinated coffee or tea and the risk of melanoma among both men and women. The consumption of caffeinated coffee was inversely associated with melanoma risk among men in this large cohort study. Further investigations are warranted to confirm our findings and clarify the possible role of caffeine and other coffee compounds in reducing the risk of melanoma. © 2017 UICC.

  5. Exploring an interaction of adenosine A2A receptor variability with coffee and tea intake in Parkinson's disease.

    Science.gov (United States)

    Tan, E K; Lu, Z Y; Fook-Chong, S M C; Tan, E; Shen, H; Chua, E; Yih, Y; Teo, Y Y; Zhao, Y

    2006-09-05

    Caffeine is an adenosine receptor A1 and A2A receptor antagonist and a putative functional genetic variant of the A2A receptor (2592C > Tins) mediates caffeine-induced anxiety. Here we investigated the potential interaction of this A2A genetic variant with the quantity of coffee and tea intake and their relationship with the risk of PD. A total of 441 subjects consisting of 222 PD and 219 race, gender and age matched controls were included. A multivariate analysis of the variables including the 2592C > Tins A2A genotypes, age of onset, gender, and the quantity of tea and coffee intake, interaction of the A2A genotypes with coffee intake, interaction of A2A genotypes with tea intake demonstrated the quantity of coffee intake to be significantly associated with PD (P coffee and tea intake in modulating the risk of PD. The dose dependent protective effect of coffee intake in PD was independent of the 2592C > Tins A2A genotype suggesting that the pharmacogenetic action of caffeine in PD may be mediated differently from other caffeine-induced neurologic syndromes.

  6. Coffee, green tea, black tea and oolong tea consumption and risk of mortality from cardiovascular disease in Japanese men and women.

    Science.gov (United States)

    Mineharu, Yohei; Koizumi, Akio; Wada, Yasuhiko; Iso, Hiroyasu; Watanabe, Yoshiyuki; Date, Chigusa; Yamamoto, Akio; Kikuchi, Shogo; Inaba, Yutaka; Toyoshima, Hideaki; Kondo, Takaaki; Tamakoshi, Akiko

    2011-03-01

    The effects of coffee and green, black and oolong teas and caffeine intake on cardiovascular disease (CVD) mortality have not been well defined in Asian countries. To examine the relationship between the consumption of these beverages and risk of mortality from CVD, 76,979 individuals aged 40-79 years free of stroke, coronary heart disease (CHD) and cancer at entry were prospectively followed. The daily consumption of beverages was assessed by questionnaires. 1362 deaths were documented from strokes and 650 deaths from CHD after 1,010,787 person-years of follow-up. Compared with non-drinkers of coffee, the multivariable HR and 95% CI for those drinking 1-6 cups/week, 1-2 cups/day and ≥ 3 cups/day were 0.78 (0.50 to 1.20), 0.67 (0.47 to 0.96) and 0.45 (0.17 to 0.87) for strokes among men (p = 0.009 for trend). Compared with non-drinkers of green tea, the multivariable HR for those drinking 1-6 cups/week, 1-2 cups/day, 3-5 cups/day and ≥ 6 cups/day were 0.34 (0.06-1.75), 0.28 (0.07-1.11), 0.39 (0.18-0.85) and 0.42 (0.17-0.88) for CHD among women (p = 0.038 for trend). As for oolong tea, the multivariable HR of those drinking 1-6 cups/week and ≥ 1 cups/day were 1.00 (0.65-1.55) and 0.39 (0.17-0.88) for total CVD among men (p = 0.049 for trend). Risk reduction for total CVD across categories of caffeine intake was most prominently observed in the second highest quintile, with a 38% lower risk among men and 22% among women. Consumption of coffee, green tea and oolong tea and total caffeine intake was associated with a reduced risk of mortality from CVD.

  7. The suitability of caffeinated drinks for children: a systematic review of randomised controlled trials, observational studies and expert panel guidelines.

    Science.gov (United States)

    Ruxton, C H S

    2014-08-01

    The increased availability of caffeinated drinks raises questions about the level of caffeine that is appropriate for children, as well as the benefits and risks associated with their consumption. Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, this systematic review evaluates evidence from randomised controlled trials investigating the effects of caffeine on cognition, behaviour, mood and exercise performance in children. Observational studies and expert panel guidelines are also discussed. One hundred and nine studies were found, with 11 randomised controlled trials and 13 observational studies meeting the criteria. High caffeine intakes (e.g. >5 mg kg(-1) body weight day(-1)) were associated with an increased risk of anxiety and withdrawal symptoms. However, smaller amounts were not linked with such effects and may benefit cognitive function and sports performance based on adult studies. The evidence suggests that children and adolescents should limit daily caffeine consumption to 2.5 mg kg(-1) body weight day(-1), equating to one or two cups of tea or one small cup of coffee. Lower contributors of caffeine, such as tea, may be more appropriate for children because they contribute to daily fluid intakes and provide flavonoids. By contrast, caffeinated soft drinks may be less suitable options for children as a result of their acidity, higher caffeine content, presence of added sugar (in some cases) and absence of bioactive compounds. More studies are needed to determine the intakes that represent a risk and whether there may be benefits for alertness and sports performance with moderate intakes of caffeine. © 2013 The British Dietetic Association Ltd.

  8. Caffeine Reinforces Flavor Preference and Behavior in Moderate Users but Not in Low Caffeine Users

    Science.gov (United States)

    Dack, Charlotte; Reed, Phil

    2009-01-01

    The study examined the role of caffeine consumption in caffeine reinforcement. Previous findings have shown that caffeine reinforced flavor preference in moderate caffeine consumers who are caffeine deprived. However, most of these studies have employed rating procedures only, and have not shown the effectiveness of caffeine to reinforce behaviors…

  9. Maternal Caffeine Consumption during Pregnancy and Behavioral Disorders in 11-Year-Old Offspring: A Danish National Birth Cohort Study.

    Science.gov (United States)

    Hvolgaard Mikkelsen, Susanne; Obel, Carsten; Olsen, Jørn; Niclasen, Janni; Bech, Bodil Hammer

    2017-10-01

    To examine the association between maternal caffeine consumption from coffee and tea during pregnancy and offspring behavioral disorders. We studied 47 491 children enrolled in the Danish National Birth Cohort between 1996 and 2002. Data on maternal coffee and tea consumption was collected at 15 and 30 weeks of gestation. When the child was 11 years old, the Strength and Difficulties Questionnaire was filled in by children, parents, and teachers. We estimated risk ratios (RRs) for offspring behavioral disorders. At 15 weeks of gestation 3% and 4% of the pregnant women consumed ≥8 cups/d of coffee or tea, respectively. Maternal coffee consumption ≥8 cups/d at 15 weeks of gestation was associated with increased risk of hyperactivity-inattention disorder (RR 1.47; 95% CI 1.18-1.83), conduct-oppositional disorders (RR 1.22; 95% CI 1.01-1.48), and any psychiatric disorder (RR 1.23; 95% CI 1.08-1.40). Maternal tea consumption ≥8 cups/d at 15 weeks of gestation was associated with increased risk of anxiety-depressive disorders (RR 1.28; 95% CI 1.09-1.52) and any psychiatric disorder (RR 1.24; 95% CI 1.11-1.40). An increased risk of hyperactivity-inattention disorder was observed with increasing daily caffeine consumption at 15 weeks of gestation. High maternal caffeine consumption from coffee and tea at 15 weeks of gestation was associated with behavioral disorders in 11-year-old offspring. We hypothesize that caffeine exposure may affect the fetal brain and program for behavioral disorders later in life. The fetal brain seems to be more sensitive to caffeine exposure at 15 weeks of pregnancy compared with 30 weeks of gestation. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Determination of catechin diastereomers from the leaves of Byrsonima species using chiral HPLC-PAD-CD.

    Science.gov (United States)

    Rinaldo, Daniel; Batista, João M; Rodrigues, Juliana; Benfatti, Ana C; Rodrigues, Clenilson M; dos Santos, Lourdes C; Furlan, Maysa; Vilegas, Wagner

    2010-08-01

    When catechins are found in plant extracts, they are almost always identified as catechin and/or epicatechin probably due to stereoselectivity of the enzymes involved in the biosynthesis of these substances. However, the lack of reports regarding to ent-catechin as well as ent-epicatechin does not necessarily mean that these compounds have not been produced. In fact, most of the previous reports used chromatographic conditions not suitable for such separation. This article describes a simple and reliable analytical HPLC-PAD-CD method for simultaneous determination of catechin diastereomers both in infusions and extracts from the leaves of Byrsonima species. The direct separation of catechin, ent-catechin, epicatechin, and ent-epicatechin was obtained in normal phase by HPLC-PAD-CD using Chiralcel OD-H as chiral stationary phase and n-hexane/ethanol with 0.1% of TFA as mobile phase. Copyright 2010 Wiley-Liss, Inc.

  11. Estimating caffeine intake from energy drinks and dietary supplements in the United States.

    Science.gov (United States)

    Bailey, Regan L; Saldanha, Leila G; Gahche, Jaime J; Dwyer, Johanna T

    2014-10-01

    No consistent definition exists for energy products in the United States. These products have been marketed and sold as beverages (conventional foods), energy shots (dietary supplements), and in pill or tablet form. Recently, the number of available products has surged, and formulations have changed to include caffeine. To help characterize the use of caffeine-containing energy products in the United States, three sources of data were analyzed: sales data, data from federal sources, and reports from the Drug Abuse Warning Network. These data indicate that sales of caffeine-containing energy products and emergency room visits involving their consumption appear to be increasing over time. Data from the National Health and Nutrition Examination Survey (NHANES) 2007-2010 indicate that 2.7% [standard error (SE) 0.2%] of the US population ≥1 year of age used a caffeine-containing energy product, providing approximately 150-200 mg/day of caffeine per day in addition to caffeine from traditional sources like coffee, tea, and colas. The highest usage of these products was among males between the ages of 19 and 30 years (7.6%, SE 1.0). Although the prevalence of caffeine-containing energy product use remains low overall in the US population, certain subgroups appear to be using these products in larger amounts. Several challenges remain in determining the level of caffeine exposure from and accurate usage patterns of caffeine-containing energy products. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  12. Mood, music, and caffeine

    NARCIS (Netherlands)

    Jolij, Jacob; Lorist, Monicque

    2014-01-01

    What we see is affected by how we feel: in positive moods, we are more sensitive to positive stimuli, such as happy faces, but in negative moods we are more sensitive to negative stimuli, such as sad faces. Caffeine is known to affect mood - a cup of coffee results in a more positive mood, but also

  13. Study on the interaction of catechins with human serum albumin using spectroscopic and electrophoretic techniques

    Science.gov (United States)

    Trnková, Lucie; Boušová, Iva; Staňková, Veronika; Dršata, Jaroslav

    2011-01-01

    The interaction between eight naturally occurring flavanols (catechin, epicatechin, gallocatechin, epigallocatechin, catechin gallate, epicatechin gallate, gallocatechin gallate, and epigallocatechin gallate) and human serum albumin (HSA) has been investigated by spectroscopic (fluorescence quenching and UV-Vis absorption) and electrophoretic (native and SDS PAGE) techniques under simulated physiological conditions (pH 7.40, 37 °C). The spectroscopic results confirmed the complex formation for the tested systems. The binding constants and the number of binding sites were obtained by analysis of fluorescence data. The strongest binding affinity to HSA was found for epicatechin gallate and decreased in the order epicatechin gallate ⩾ catechin gallate > epigallocatechin gallate > gallocatechin gallate ≫ epicatechin ⩾ catechin > gallocatechin ⩾ epigallocatechin. All free energy changes possessed negative sign indicating the spontaneity of catechin-HSA systems formation. The binding distances between the donor (HSA) and the acceptors (catechins) estimated by the Förster theory revealed that non-radiation energy transfer from HSA to catechins occurred with high possibility. According to results obtained by native PAGE, the galloylated catechins increased the electrophoretic mobility of HSA, which indicated the change in the molecular charge of HSA, whilst the non-galloylated catechins caused no changes. The ability of aggregation and cross-linking of tested catechins with HSA was not proved by SDS-PAGE. The relationship between the structure characteristics of all tested catechins (e.g. presence of the galloyl moiety on the C-ring, the number of hydroxyl groups on the B-ring, and the spatial arrangement of the substituents on the C-ring) and their binding properties to HSA is discussed. The presented study contributes to the current knowledge in the area of protein-ligand binding, particularly catechin-HSA interactions.

  14. Tea and Cardiovascular Disease

    Science.gov (United States)

    Deka, Apranta; Vita, Joseph A.

    2011-01-01

    There is increasing evidence for a protective effect of tea consumption against cardiovascular disease. This review summarizes the available epidemiological data providing evidence for and against such an effect. We also review observational and intervention studies that investigated an effect of tea and tea extracts on cardiovascular risk factors, including blood pressure, serum lipids, diabetes mellitus, and obesity. Finally, we review potential mechanisms of benefit, including anti-inflammatory, anti-oxidant, and anti-proliferative effects, as well as favorable effects on endothelial function. Overall, the observational data suggest a benefit, but results are mixed and likely confounded by lifestyle and background dietary factors. The weight of evidence indicates favorable effects on risk factors and a number of plausible mechanisms have been elucidated in experimental and translational human studies. Despite the growing body evidence, it remains uncertain whether tea consumption should be recommended to the general population or to patients as a strategy to reduce cardiovascular risk. PMID:21477653

  15. Tea Tree Oil

    Science.gov (United States)

    ... of Grants and Contracts General Award Mechanisms Small Business Research Grant Program (SBIR) Funding for: Natural Product ... cuts and wounds by the aboriginal people of Australia. Today, tea tree oil is often used externally ...

  16. Caffeine and sports performance.

    Science.gov (United States)

    Burke, Louise M

    2008-12-01

    Athletes are among the groups of people who are interested in the effects of caffeine on endurance and exercise capacity. Although many studies have investigated the effect of caffeine ingestion on exercise, not all are suited to draw conclusions regarding caffeine and sports performance. Characteristics of studies that can better explore the issues of athletes include the use of well-trained subjects, conditions that reflect actual practices in sport, and exercise protocols that simulate real-life events. There is a scarcity of field-based studies and investigations involving elite performers. Researchers are encouraged to use statistical analyses that consider the magnitude of changes, and to establish whether these are meaningful to the outcome of sport. The available literature that follows such guidelines suggests that performance benefits can be seen with moderate amounts (~3 mg.kg-1 body mass) of caffeine. Furthermore, these benefits are likely to occur across a range of sports, including endurance events, stop-and-go events (e.g., team and racquet sports), and sports involving sustained high-intensity activity lasting from 1-60 min (e.g., swimming, rowing, and middle and distance running races). The direct effects on single events involving strength and power, such as lifts, throws, and sprints, are unclear. Further studies are needed to better elucidate the range of protocols (timing and amount of doses) that produce benefits and the range of sports to which these may apply. Individual responses, the politics of sport, and the effects of caffeine on other goals, such as sleep, hydration, and refuelling, also need to be considered.

  17. [Relationship between the anti-hemolysin activity and the structure of catechins and theaflavins].

    Science.gov (United States)

    Ikigai, H; Toda, M; Okubo, S; Hara, Y; Shimamura, T

    1990-11-01

    We examined the corresponding isomers of catechins and theaflavins for anti-hemolysin activities against Staphylococcus aureus alpha-toxin and Vibrio cholerae O1 hemolysin. Catechins and theaflavins showed anti-hemolysin activities in a dose-dependent manner. Among the catechins tested, (-)catechin gallate, (-)epicatechin gallate and (-)epigallocatechin gallate having galloyl groups in their molecules showed more potent anti-hemolysin activities against both toxins. On the other hand, free catechins, i. e. (-)catechin, (-)gallocatechin, (-) epicatechin and (-)epigallocatechin had low anti-hemolysin activities against alpha-toxin. Although (-)catechin or (-)gallocatechin had no effect on cholera hemolysin, (-) epicatechin and (-)epigallocatechin were slightly inhibitory. Among dextrocatechins, (+) epicatechin and (+)epigallocatechin proved to be more effective than (+)catechin and (+) gallocatechin. The anti-hemolysin activities of theaflavins against alpha-toxin and cholera hemolysin were dependent on the number of the galloyl group in their structure. These results suggest that the tertiary structure of the catechin or theaflavin and the active site of hemolysin, that affects the interaction between them, plays an important role in the anti-hemolysin activity.

  18. Exploring the possible applications of catechin (gel for oral care of the elderly and disabled individuals

    Directory of Open Access Journals (Sweden)

    Muneaki Tamura

    2012-08-01

    Full Text Available The oral cavity contains more than hundreds of microbial species. An increase in the number of these microorganisms like high pathogenic potential species, such as cariogenic and periodontopathic bacteria, and the change of microbial biota may result in, not only oral infection, but also systemic diseases, such as infective endocarditis and aspiration pneumonia. It is very important to control the growth of these microorganisms and its biota just after oral cleaning in order to suppress disease onset. In this regard, it is useful to use the anti-microbial component which acts against pathogenic microorganisms. Here, we highlight the importance of catechin, and feature its possible oral, especially periodontal applications. By combining catechin with gel (catechin gel, antimicrobial activity of catechin was prolonged in gel and catechin anti-oxidization property was observed. Catechin gel inhibited the growth of the Actinomyces, periodontopathic bacteria and Candida strains tested, but did not inhibit that of the oral streptococci that are important in the normal oral flora. In contrast, commercially available moisture gels containing antimicrobial components showed antimicrobial activity against all of the tested strains including the oral streptococci. This show that catechin has selective antimicrobial activity, attributable to hydrogen peroxide production. This paper reviews previous works using catechin and, likewise, catechin gel may be show its possible oral application for prevent dental caries and periodontal disease.

  19. Interaction and release of catechin from anhydride maleic-grafted polypropylene films.

    Science.gov (United States)

    López de Dicastillo, Carol; Castro-López, Maria Del Mar; Lasagabaster, Aurora; López-Vilariño, Jose M; González-Rodríguez, M Victoria

    2013-04-24

    In this paper, investigations were carried out on catechin-loaded maleic anhydride (MAH)-modified polypropylenes (PP). Two maleic-modified polypropylenes (PPMAH) with different maleic concentrations have been blended with PP and catechin to obtain composites of improved catechin retention with the aim of studying the possible interactions between these grafted polymers with antioxidants, and a secondary interest in developing an active antioxidant packaging. Composite physicochemical properties were measured by thermal analysis (thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and oxidation induction time (OIT)) and infrared spectroscopy studies. Catechin release profiles into food simulants were obtained by HPLC-PDA-QqQ, following European legislation. Antiradical activity of composites was analyzed by the ABTS and DPPH method. The formation of intermolecular hydrogen bonds between catechin and functionalized PP has been confirmed by Fourier transform infrared (FTIR) studies. Besides, a small fraction of ester bonds, formed as a result of a chemical reaction between a fraction of the hydrolyzed anhydride and the catechin hydroxyl groups, is not discarded. OIT results also showed an increase in antioxidant effectiveness caused by the presence of catechin- and maleic-modified PPMAH in the blend formulations. Incorporation of MAH-grafted PP increased substantially the retention rate of catechin, being dependent on the MAH content of the grafted polypropylene. The described interactions between catechin and maleic groups, together with changes in PP morphology in comparison with reference PP explained lower antioxidant release. Besides formulation, antioxidant release was dependent on the type of food, the temperature, and the time.

  20. Chemistry of Secondary Polyphenols Produced during Processing of Tea and Selected Foods

    Directory of Open Access Journals (Sweden)

    Takashi Tanaka

    2009-12-01

    Full Text Available This review will discuss recent progress in the chemistry of secondary polyphenols produced during food processing. The production mechanism of the secondary polyphenols in black tea, whisky, cinnamon, and persimmon fruits will be introduced. In the process of black tea production, tea leaf catechins are enzymatically oxidized to yield a complex mixture of oxidation products, including theaflavins and thearubigins. Despite the importance of the beverage, most of the chemical constituents have not yet been confirmed due to the complexity of the mixture. However, the reaction mechanisms at the initial stages of catechin oxidation are explained by simple quinone–phenol coupling reactions. In vitro model experiments indicated the presence of interesting regio- and stereoselective reactions. Recent results on the reaction mechanisms will be introduced. During the aging of whisky in oak wood barrels, ellagitannins originating from oak wood are oxidized and react with ethanol to give characteristic secondary ellagitannins. The major part of the cinnamon procyanidins is polymerized by copolymerization with cinnamaldehyde. In addition, anthocyanidin structural units are generated in the polymer molecules by oxidation which accounts for the reddish coloration of the cinnamon extract. This reaction is related to the insolubilization of proanthocyanidins in persimmon fruits by condensation with acetaldehyde. In addition to oxidation, the reaction of polyphenols with aldehydes may be important in food processing.

  1. DNA degradation by water extract of green tea in the presence of copper ions: implications for anticancer properties.

    Science.gov (United States)

    Malik, Arshi; Azam, Sonish; Hadi, Naghma; Hadi, S M

    2003-04-01

    In recent years a number of reports have documented the chemopreventive effect of green tea consumption on various types of cancers such as those of bladder, prostate, esophagus and stomach. This property is attributed to the presence in green tea of polyphenols known as catechins. These include epigallocatechin-3-gallate, epigallocatechin and epicatechin. In addition to their antioxidant properties plant derived polyphenolics are also capable of oxidative DNA damage particularly in the presence of transition metal ions. We have recently proposed a mechanism for cytotoxic action of plant-derived polyphenols against cancer cells that involves mobilization of endogenous copper and consequent prooxidant action. In partial support of the idea, in the present paper we show that water extract of green tea is considerably more efficient than black tea extract in DNA cleavage in the presence of copper ions. Green tea extract also shows a higher rate of Cu(II) reduction and consequent hydroxyl radical formation. Cu(II) reduction is presumably accompanied by the formation of 'oxidized species' of tea polyphenols, which in turn also appear to catalyze the reduction of Cu(II) leading to redox cycling of copper ions. The results are discussed in relation to the structural differences between polyphenols of green and black tea. Copyright 2003 John Wiley & Sons, Ltd.

  2. In vitro antioxidant capacity of tea of Echinodorus grandiforus, “leather hat,” in Wistar rat liver

    Directory of Open Access Journals (Sweden)

    RAFAELA F. LUNARDI

    2014-09-01

    Full Text Available Oxidative stress has been considered as one of the factors responsible for hepatic diseases, which sometimes require new ways of treatment. The present study aimed to evaluate the in vitro antioxidant capacity of the tea of Echinodorus grandiforus (“leather hat” plant in rat liver. Different preparations of tea were evaluated for phenolic composition, antioxidant activity by DPPH assay and ability to inhibit lipid peroxidation induced by copper sulfate. The antioxidant activity was assessed in liver tissue treated with sodium azide in the presence or absence of tea by assays for lipid peroxidation (TBARS, protein oxidation (carbonyl and the antioxidant enzymes catalase (CAT and superoxide dismutase (SOD. The results show that different preparations of tea are important sources of polyphenols and contain theobromine, catechin and vitexin. Furthermore, the results indicate that this tea exhibits an antioxidant activity by its ability to scavenge DPPH radical. Different preparations of tea prevented damage to lipids and proteins induced by sodium azide, as well as assisting in restoring CAT and SOD activities. Thus, it can be seen that E. grandiforus tea had antioxidant activity in serum and liver being able to prevent oxidative damages generated by sodium azide.

  3. Kombucha tea fermentation: Microbial and biochemical dynamics.

    Science.gov (United States)

    Chakravorty, Somnath; Bhattacharya, Semantee; Chatzinotas, Antonis; Chakraborty, Writachit; Bhattacharya, Debanjana; Gachhui, Ratan

    2016-03-02

    Kombucha tea, a non-alcoholic beverage, is acquiring significant interest due to its claimed beneficial properties. The microbial community of Kombucha tea consists of bacteria and yeast which thrive in two mutually non-exclusive compartments: the soup or the beverage and the biofilm floating on it. The microbial community and the biochemical properties of the beverage have so far mostly been described in separate studies. This, however, may prevent understanding the causal links between the microbial communities and the beneficial properties of Kombucha tea. Moreover, an extensive study into the microbial and biochemical dynamics has also been missing. In this study, we thus explored the structure and dynamics of the microbial community along with the biochemical properties of Kombucha tea at different time points up to 21 days of fermentation. We hypothesized that several biochemical properties will change during the course of fermentation along with the shifts in the yeast and bacterial communities. The yeast community of the biofilm did not show much variation over time and was dominated by Candida sp. (73.5-83%). The soup however, showed a significant shift in dominance from Candida sp. to Lachancea sp. on the 7th day of fermentation. This is the first report showing Candida as the most dominating yeast genus during Kombucha fermentation. Komagateibacter was identified as the single largest bacterial genus present in both the biofilm and the soup (~50%). The bacterial diversity was higher in the soup than in the biofilm with a peak on the seventh day of fermentation. The biochemical properties changed with the progression of the fermentation, i.e., beneficial properties of the beverage such as the radical scavenging ability increased significantly with a maximum increase at day 7. We further observed a significantly higher D-saccharic acid-1,4-lactone content and caffeine degradation property compared to previously described Kombucha tea fermentations. Our

  4. Fluoride and aluminum in teas and tea-based beverages

    Directory of Open Access Journals (Sweden)

    Hayacibara Mitsue Fujimaki

    2004-01-01

    Full Text Available OBJECTIVE: To evaluate fluoride and aluminum concentration in herbal, black, ready-to-drink, and imported teas available in Brazil considering the risks fluoride and aluminum pose to oral and general health, respectively. METHODS: One-hundred and seventy-seven samples of herbal and black tea, 11 types of imported tea and 21 samples of ready-to-drink tea were divided into four groups: I-herbal tea; II-Brazilian black tea (Camellia sinensis; III-imported tea (Camellia sinensis; IV-ready-to-drink tea-based beverages. Fluoride and aluminum were analyzed using ion-selective electrode and atomic absorption, respectively. RESULTS: Fluoride and aluminum levels in herbal teas were very low, but high amounts were found in black and ready-to-drink teas. Aluminum found in all samples analyzed can be considered safe to general health. However, considering 0.07 mg F/kg/day as the upper limit of fluoride intake with regard to undesirable dental fluorosis, some teas exceed the daily intake limit for children. CONCLUSIONS: Brazilian and imported teas made from Camellia sinensis as well as some tea-based beverages are sources of significant amounts of fluoride, and their intake may increase the risk of developing dental fluorosis.

  5. Augmentation of antidepressant effects of duloxetine and bupropion by caffeine in mice.

    Science.gov (United States)

    Kale, Pravin Popatrao; Addepalli, Veeranjaneyulu

    2014-09-01

    There is an unmet need in the treatment of depression suggesting requirement of new therapeutic approaches having better efficacy and safety profile. Patients receiving antidepressant therapy generally consume caffeine in the form of tea or coffee. The objective of the present study was to evaluate the augmentation of antidepressant effects of duloxetine and/or bupropion with caffeine. Male Swiss Albino mice received treatment of normal saline (10 ml/kg), 'caffeine alone' (10mg/kg), 'duloxetine alone' (10mg/kg), 'bupropion alone' (10mg/kg), caffeine+duloxetine (5mg/kg, each), bupropion+caffeine (5mg/kg, each), and bupropion+duloxetine (5mg/kg, each) through the intra-peritoneal route. The immobility period was analyzed 30 min after the treatment in forced swim and tail suspension tests. Norepinephrine, dopamine, and serotonin levels were analyzed in hippocampus, cerebral cortex and whole brain using HPLC with fluorescence detector. Euthanasia was performed 1h after treatment. Comparison between vehicle treated group and other groups showed significant decrease in immobility in all drug treated groups in both antidepressant models. Caffeine plus duloxetine treated group was better among the combination treated groups in terms of decrease in immobility and increase in norepinephrine, dopamine, and serotonin levels in hippocampi, cerebral cortices, and whole brain when compared to their respective monotherapy treated groups. These combination approaches may help in reducing the dose of duloxetine/bupropion, and consequently lower the associated side/adverse effects. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Caffeine and risk of atrial fibrillation or flutter: the Danish Diet, Cancer, and Health Study.

    Science.gov (United States)

    Frost, Lars; Vestergaard, Peter

    2005-03-01

    It is not known whether the consumption of caffeine is associated with excess risk of atrial fibrillation. We evaluated the risk of atrial fibrillation or flutter in association with daily consumption of caffeine from coffee, tea, cola, cocoa, and chocolate. We prospectively examined the association between the amount of caffeine consumed per day and the risk of atrial fibrillation or flutter among 47 949 participants (x age: 56 y) in the Danish Diet, Cancer, and Health Study. Subjects were followed in the Danish National Registry of Patients and in the Danish Civil Registration System. The consumption of caffeine was analyzed by quintiles with Cox proportional-hazard models. During follow-up (x: 5.7 y), atrial fibrillation or flutter developed in 555 subjects (373 men and 182 women). When the lowest quintile of caffeine consumption was used as a reference, the adjusted hazard ratios (95% CIs) in quintiles 2, 3, 4, and 5 were 1.12 (0.87, 1.44), 0.85 (0.65, 1.12), 0.92 (0.71, 1.20), and 0.91 (0.70, 1.19), respectively. Consumption of caffeine was not associated with risk of atrial fibrillation or flutter.

  7. Phenolic compounds of green tea: Health benefits and technological application in food

    Directory of Open Access Journals (Sweden)

    José Manuel Lorenzo

    2016-08-01

    Full Text Available Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodegenerative diseases. Particularly, epigallocatechin gallate has been implicated in alteration mechanisms with protective effect in these diseases as indicated by several studies about the effect of green tea consumption and mechanistic explanation through in vitro and in vivo experiments. The biological activity of green tea phenolic compounds also promotes a protective effect by antioxidant mechanisms in biological and food systems, preventing the oxidative damage by acting over either precursors or reactive species. Extraction of phenolic compounds influences the antioxidant activity and promotes adequate separation from green tea leaves to enhance the yield and/or antioxidant activity. Application of green tea phenolic compounds is of great interest because the antioxidant status of the products is enhanced and provides the product with additional antioxidant activity or reduces the undesirable changes of oxidative reactions while processing or storing food. In this scenario, meat and meat products are greatly influenced by oxidative deterioration and microbial spoilage, leading to reduced shelf life. Green tea extracts rich in phenolic compounds have been applied to increase shelf life with comparable effect to synthetic compounds, commonly used by food industry. Green tea has great importance in general health in technological application, however more studies are necessary to elucidate the impact in pathways related to other diseases and food

  8. Caffeinated alcohol use and expectancies for caffeine versus alcohol.

    Science.gov (United States)

    Lau-Barraco, Cathy; Linden, Ashley N

    2014-08-01

    Caffeinated alcoholic beverage (CAB) use is related to alcohol-related risk. Limited research has examined outcome expectancies and CAB consumption. This study tested the predictive utility of caffeine and alcohol expectancies in CAB use outcomes (i.e. quantity, frequency, and alcohol-related harms). Participants were 419 (302 women) alcohol and caffeine users from a mid-sized urban university. Data collection occurred between August 2010 and December 2011. Participants completed measures of caffeine and alcohol expectancies, alcohol problems, alcohol use, and CAB use. Caffeine and alcohol expectancies contributed uniquely to approximately 12% of the variability in quantity, 8% in frequency, and 16% in problems. When examined separately, alcohol expectancies explained approximately 10% to 11% of the variance, whereas caffeine expectancies accounted for 6% of the variance in CAB use quantity. For CAB use frequency, alcohol and caffeine expectancies accounted for about 8% and 4%, respectively. Alcohol expectancies accounted for 12% to 14% of variance, whereas caffeine expectancies accounted for 4% to 6% in alcohol-related harms. CONCLUSIONS/ IMPORTANCE: The present study sought to address a gap in the literature regarding the contributions of expectancies in the prediction of CAB use. Our findings provide support for the predictive utility of both caffeine and alcohol expectancies in accounting for individual variability in CAB use but alcohol expectancies may exert greater impact on use patterns. Inclusion of both types of expectancies in larger theoretical frameworks may be beneficial in gaining a more complete and deeper conceptualization of this risky behavior.

  9. Coffee and tea consumption and risk of pre- and postmenopausal breast cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort study

    OpenAIRE

    Bhoo-Pathy, Nirmala; Peeters, Petra H M; Uiterwaal, Cuno S P M; Bueno-de-Mesquita, H. Bas; Bulgiba, Awang M.; Bech, Hammer H.; Overvad, Kim; Tjønneland, Anne; Olsen, Anja; Clavel-Chapelon, Françoise; Fagherazzi, Guy; Perquier, Florence; Teucher, Birgit; Kaaks, Rudolf; Schütze, Madlen

    2015-01-01

    Introduction Specific coffee subtypes and tea may impact risk of pre- and post-menopausal breast cancer differently. We investigated the association between coffee (total, caffeinated, decaffeinated) and tea intake and risk of breast cancer. Methods A total of 335,060 women participating in the European Prospective Investigation into Nutrition and Cancer (EPIC) Study, completed a dietary questionnaire from 1992 to 2000, and were followed-up until 2010 for incidence of breast cancer. Hazard ra...

  10. Method for recovering aroma concentrate from a caffeine- or theobromine-comprising food base material

    OpenAIRE

    Kattenberg, H.R.; Willemsen, J.H.A.; Starmans, D.A.J.; Hoving, H.D.; Winters, M.G.M.

    2002-01-01

    Described is a method for recovering aroma concentrate from a caffeine- or theobromine-comprising food base material, such as coffee or tea, and in particular cocoa, at least comprising the steps of: introducing the food base material into an aqueous extractant and incubating the food base material at a suitable temperature and for a suitable period, substantial extraction of the aromas taking place to form an aqueous food extract, pervaporating the food extract using a hydrophobic pervaporat...

  11. Estimation of Theaflavins (TF) and Thearubigins (TR) Ratio in Black Tea Liquor Using Electronic Vision System

    Science.gov (United States)

    Akuli, Amitava; Pal, Abhra; Ghosh, Arunangshu; Bhattacharyya, Nabarun; Bandhopadhyya, Rajib; Tamuly, Pradip; Gogoi, Nagen

    2011-09-01

    Quality of black tea is generally assessed using organoleptic tests by professional tea tasters. They determine the quality of black tea based on its appearance (in dry condition and during liquor formation), aroma and taste. Variation in the above parameters is actually contributed by a number of chemical compounds like, Theaflavins (TF), Thearubigins (TR), Caffeine, Linalool, Geraniol etc. Among the above, TF and TR are the most important chemical compounds, which actually contribute to the formation of taste, colour and brightness in tea liquor. Estimation of TF and TR in black tea is generally done using a spectrophotometer instrument. But, the analysis technique undergoes a rigorous and time consuming effort for sample preparation; also the operation of costly spectrophotometer requires expert manpower. To overcome above problems an Electronic Vision System based on digital image processing technique has been developed. The system is faster, low cost, repeatable and can estimate the amount of TF and TR ratio for black tea liquor with accuracy. The data analysis is done using Principal Component Analysis (PCA), Multiple Linear Regression (MLR) and Multiple Discriminate Analysis (MDA). A correlation has been established between colour of tea liquor images and TF, TR ratio. This paper describes the newly developed E-Vision system, experimental methods, data analysis algorithms and finally, the performance of the E-Vision System as compared to the results of traditional spectrophotometer.

  12. Two New Monoterpene Glycosides from Qing Shan Lu Shui Tea with Inhibitory Effects on Leukocyte-Type 12-Lipoxygenase Activity

    Directory of Open Access Journals (Sweden)

    Ding Zhi Fang

    2013-04-01

    Full Text Available We evaluated the inhibitory effect of 12 Chinese teas on leukocyte-type 12-lipoxygenase (LOX activity. Tea catechins such as epigallocatechin gallate have been known to exhibit leukocyte-type 12-LOX inhibition. Qing Shan Lu Shui, which contains lower catechin levels than the other tested teas, suppressed leukocyte-type 12-LOX activity. To characterize the bioactive components of Qing Shan Lu Shui, leukocyte-type 12-LOX inhibitory activity–guided fractionation of the aqueous ethanol extract of the tea was performed, resulting in the isolation of two new monoterpene glycosides: liguroside A (1 and B (2. The structures of compounds 1 and 2 were characterized as (2E,5E-7-hydroperoxy-3,7-dimethyl-2,5-octadienyl-O-(α-L-rhamnopyranosyl-(1″→3′-(4′″-O-trans-p-coumaroyl-β-D-glucopyranoside and (2E,5E-7-hydroperoxy-3,7-dimethyl-2,5-octa-dienyl- O-(α-L-rhamnopyranosyl-(1″→3′-(4′″-O-cis-p-coumaroyl-β-D-glucopyranoside, respectively, based on spectral and chemical evidence. Ligurosides A (1 and B (2 showed inhibitory effects on leukocyte-type 12-LOX activity, with IC50 values of 1.7 and 0.7 μM, respectively.

  13. Caffeine Intake from Food and Beverage Sources and Trends among Children and Adolescents in the United States: Review of National Quantitative Studies from 1999 to 201112345

    Science.gov (United States)

    Ahluwalia, Namanjeet; Herrick, Kirsten

    2015-01-01

    There is increasing concern about potential adverse effects of caffeine in children. Our understanding of caffeine intake relies on studies dating to the late 1990s. This article synthesizes information from national studies since then to describe caffeine consumption, its association with sociodemographic factors, key dietary sources including caffeine-containing energy drinks (CCEDs), and trends in caffeine intake and sources among US children. Findings from the Kanter Worldpanel (KWP) Beverage Consumption Panel and the NHANES showed that caffeine consumption prevalence was generally consistent across studies and over time; more than one-half of 2- to 5-y-olds and ∼75% of older children (>5 y) consumed caffeine. The usual intakes of caffeine were 25 and 50 mg/d for children and adolescents aged 2–11 and 12–17 y, respectively (NHANES 2007–2010). Caffeine consumption correlated with age and was higher in non-Hispanic white children. The key sources of caffeine were soda and tea as well as flavored dairy (for children aged caffeine intake was noted in children overall during the 10- to 12-y period examined; intakes remained stable among older children (≥12 y). A significant increasing trend in CCED and coffee consumption and a decline in soda intake were noted (1999–2010). In 2009–2010, 10% of 12- to 19-y-olds and 10–25% of caffeine consumers (aged 12–19 y) had intakes exceeding Canadian maximal guidelines. Continued monitoring can help better understand changes in caffeine consumption patterns of youth. PMID:25593149

  14. Caffeine intake from food and beverage sources and trends among children and adolescents in the United States: review of national quantitative studies from 1999 to 2011.

    Science.gov (United States)

    Ahluwalia, Namanjeet; Herrick, Kirsten

    2015-01-01

    There is increasing concern about potential adverse effects of caffeine in children. Our understanding of caffeine intake relies on studies dating to the late 1990s. This article synthesizes information from national studies since then to describe caffeine consumption, its association with sociodemographic factors, key dietary sources including caffeine-containing energy drinks (CCEDs), and trends in caffeine intake and sources among US children. Findings from the Kanter Worldpanel (KWP) Beverage Consumption Panel and the NHANES showed that caffeine consumption prevalence was generally consistent across studies and over time; more than one-half of 2- to 5-y-olds and ∼75% of older children (>5 y) consumed caffeine. The usual intakes of caffeine were 25 and 50 mg/d for children and adolescents aged 2-11 and 12-17 y, respectively (NHANES 2007-2010). Caffeine consumption correlated with age and was higher in non-Hispanic white children. The key sources of caffeine were soda and tea as well as flavored dairy (for children aged coffee (for those aged ≥12 y). The frequency of CCED use varied (2-30%) depending on study setting, methods, and demographic characteristics. A statistically significant but small decline in caffeine intake was noted in children overall during the 10- to 12-y period examined; intakes remained stable among older children (≥12 y). A significant increasing trend in CCED and coffee consumption and a decline in soda intake were noted (1999-2010). In 2009-2010, 10% of 12- to 19-y-olds and 10-25% of caffeine consumers (aged 12-19 y) had intakes exceeding Canadian maximal guidelines. Continued monitoring can help better understand changes in caffeine consumption patterns of youth. © 2015 American Society for Nutrition.

  15. Evaluating Dependence Criteria for Caffeine

    OpenAIRE

    Striley, Catherine L.W.; Griffiths, Roland R.; Cottler, Linda B.

    2011-01-01

    Background: Although caffeine is the most widely used mood-altering drug in the world, few studies have operationalized and characterized Diagnostic and Statistical Manual IV (DSM-IV) substance dependence criteria applied to caffeine. Methods: As a part of a nosological study of substance use disorders funded by the National Institute on Drug Abuse, we assessed caffeine use and dependence symptoms among high school and college students, drug treatment patients, and pain clinic patients who re...

  16. Effect of green tea on kidney tubules of diabetic rats.

    Science.gov (United States)

    Renno, Waleed M; Abdeen, Suad; Alkhalaf, Mousa; Asfar, Sami

    2008-09-01

    It has been documented that green tea (GT) and its catechin components improve renal failure and inhibit the growth of mesangial cells. In the present study we examined the long-term effect of GT extract on streptozotocin (STZ)-induced diabetic nephropathy and on the glycogen accumulation in the kidney tubules. Male Sprague-Dawley rats were randomly assigned to normal control groups (2, 6, 8 and 12 weeks) and five diabetic groups (n 10) of comparable age. A GT diabetic group received 16 % concentration of GT for 12 weeks post-diabetes induction as their sole source of drinking water. GT treatment significantly (P kidney tubules. These results indicate that in STZ diabetes, kidney function appears to be improved with GT consumption which also prevents glycogen accumulation in the renal tubules, probably by lowering blood levels of glucose. Therefore, GT could be beneficial additional therapy in the management of diabetic nephropathy.

  17. Green tea as a source of food antioxidants

    DEFF Research Database (Denmark)

    Yin, Jie

    . The present study focuses on lipid oxidation and the Maillard reaction (known as nonenzymatic browning). Lipid oxidation in foods is mainly related to the unsaturated lipids, and the Maillard reactions is a ubiquitous reaction between reducing sugars and amino groups as found in amino acids, peptides...... and proteins. Lipid oxidation as well as the Maillard reactions can affect the quality of foods. An efficient way to retard or inhibit both types of reactions can be achieved by utilizing natural antioxidants, which are normally presumed to be safe when the source is plant material, “Generally Recognized...... during the Maillard reactions by ESR. A mechanistic study of influencing Maillard reaction products by green tea catechins was mainly explored by liquid chromatography-mass spectrometry (LC-MS). The results revealed that the quinone form of EC can undergo either a Michael type addition or a “Strecker...

  18. Minimum Tea Hectarage Hypothesis: The Case of Smallholder Tea ...

    African Journals Online (AJOL)

    Tea is planted in the high potential and prime lands in the humid and per-humid agro-ecological zones. The population pressure in the tea growing districts is relatively higher than that of the neighbouring districts without the enterprise. The average area under tea in the smallholder sub-sector is approximately 0.27 ha.

  19. Antidepressive-like effects and antioxidant activity of green tea and GABA green tea in a mouse model of post-stroke depression.

    Science.gov (United States)

    Di Lorenzo, Arianna; Nabavi, Seyed Fazel; Sureda, Antoni; Moghaddam, Akbar Hajizadeh; Khanjani, Sedigheh; Arcidiaco, Patrizia; Nabavi, Seyed Mohammad; Daglia, Maria

    2016-03-01

    Growing evidence suggests that oxidative stress plays a role in the development of chronic diseases such as cardiovascular disease and some psychiatric disorders. Tea consumption exerts beneficial effects against damage induced by cerebral ischemia-reperfusion in ischemic stroke and depressive symptoms in depression. The aim of this study was to evaluate, in vivo, the protective activity of green tea (GT) and GABA green tea (GGT) against post-stroke depression (PSD), a common consequence of stroke. The antidepressive-like effects of GT and GGT were determined by behavioral tests in a mouse model of post-stroke depression. The antioxidant activity was evaluated by GSH, SOD, and TBARS measurements on mouse brain. The chemical composition of tea extracts was characterized through chromatographic methods. GGT and GT resulted active in the modulation of depressive symptoms and the reduction of oxidative stress, restoring normal behavior, and at least in part, antioxidant endogenous defenses. The higher polyphenol, theanine, glutamine, and caffeine content may justify the higher activity found in GGT. This work represents the first attempt to demonstrate the positive effect of tea, and especially GGT, on post-stroke depression and to correlate this effect with the antioxidant activity and phytochemical composition of tea. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Effects of tea polyphenol components on reversion of tumor multidrug resistance

    International Nuclear Information System (INIS)

    Ran Tiecheng; Wang Yi; Liu Xinqi; Chu Taiwei; Wei Xionghui; Wang Xiangyun; Guo Zhenquan; Wei Bing

    2003-01-01

    The effects of tea polyphenol (TP) and its main components, (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG) with caffeine on reversion of tumor multidrug resistance (MDR) are investigated by using MCF-7/Adr cell line and 99 Tc m -MIBI as a substrate of P-glucoprotein (P-gp). MCF-7/Adr cells are incubated with 99 Tc m -MIBI in the presence or absence of TP or its main components (separate or mixed). The cell uptake of 99 Tc m -MIBI is measured and compared with a contrast to estimate the MDR reversion effect. The experimental results indicate that the native tea polyphenol exhibits a moderate MDR reversion effect. The MDR reversion efficacies of the four main components of TP are found in the sequence ECG>EGC>EC>EGCG. Caffeine as well as the mixture of EGCG-ECG-EGC-EC in the mass ratio 10:3:2:1 shows practically no MDR reversion effect

  1. Optimization of ultrasonic extraction of phenolic antioxidants from green tea using response surface methodology.

    Science.gov (United States)

    Lee, Lan-Sook; Lee, Namhyouck; Kim, Young Ho; Lee, Chang-Ho; Hong, Sang Pil; Jeon, Yeo-Won; Kim, Young-Eon

    2013-10-31

    Response surface methodology (RSM) has been used to optimize the extraction conditions of antioxidants with relatively low caffeine content from green tea by using ultrasonic extraction. The predicted optimal conditions for the highest antioxidant activity and minimum caffeine level were found at 19.7% ethanol, 26.4 min extraction time, and 24.0 ° C extraction temperature. In the predicted optimal conditions, the experimental values were very close to the predicted values. Moreover, the ratio of (EGCg + ECg)/EGC was identified a major factor contributing to the antioxidant activity of green tea extracts. In this study, ultrasonic extraction showed that the ethanol concentration and extraction time used for antioxidant extraction could be remarkably reduced without a decrease in antioxidant activity compared to the conventional extraction conditions.

  2. Green tea polyphenols provide photoprotection, increase microcirculation, and modulate skin properties of women.

    Science.gov (United States)

    Heinrich, Ulrike; Moore, Carolyn E; De Spirt, Silke; Tronnier, Hagen; Stahl, Wilhelm

    2011-06-01

    Dietary constituents including polyphenols and carotenoids contribute to endogenous photoprotection and modulate skin characteristics related to structure and function of the tissue. Animal and in-vitro studies indicate that green tea polyphenols affect skin properties. In a 12-wk, double-blind, placebo-controlled study, 60 female volunteers were randomized to an intervention or control group. Participants consumed either a beverage with green tea polyphenols providing 1402 mg total catechins/d or a control beverage. Skin photoprotection, structure, and function were measured at baseline (wk 0), wk 6, and wk 12. Following exposure of the skin areas to 1.25 minimal erythemal dose of radiation from a solar simulator, UV-induced erythema decreased significantly in the intervention group by 16 and 25% after 6 and 12 wk, respectively. Skin structural characteristics that were positively affected included elasticity, roughness, scaling, density, and water homeostasis. Intake of the green tea polyphenol beverage for 12 wk increased blood flow and oxygen delivery to the skin. Likewise, in a separate, randomized, double-blind, single-dose (0.5, 1.0, and 2.0 g) study of green tea polyphenols, blood flow was maximized at 30 min after ingestion. In summary, green tea polyphenols delivered in a beverage were shown to protect skin against harmful UV radiation and helped to improve overall skin quality of women.

  3. Differentiation of tea varieties using UV-Vis spectra and pattern recognition techniques

    Science.gov (United States)

    Palacios-Morillo, Ana; Alcázar, Ángela.; de Pablos, Fernando; Jurado, José Marcos

    2013-02-01

    Tea, one of the most consumed beverages all over the world, is of great importance in the economies of a number of countries. Several methods have been developed to classify tea varieties or origins based in pattern recognition techniques applied to chemical data, such as metal profile, amino acids, catechins and volatile compounds. Some of these analytical methods become tedious and expensive to be applied in routine works. The use of UV-Vis spectral data as discriminant variables, highly influenced by the chemical composition, can be an alternative to these methods. UV-Vis spectra of methanol-water extracts of tea have been obtained in the interval 250-800 nm. Absorbances have been used as input variables. Principal component analysis was used to reduce the number of variables and several pattern recognition methods, such as linear discriminant analysis, support vector machines and artificial neural networks, have been applied in order to differentiate the most common tea varieties. A successful classification model was built by combining principal component analysis and multilayer perceptron artificial neural networks, allowing the differentiation between tea varieties. This rapid and simple methodology can be applied to solve classification problems in food industry saving economic resources.

  4. Antioxidant Activity of Aqueous Tea Infusions Prepared from Oregano, Thyme and Wild Thyme

    Directory of Open Access Journals (Sweden)

    Tea Kulišić

    2006-01-01

    Full Text Available Using a multiple-method approach, antioxidant activity of aqueous tea infusions prepared from oregano (Origanum vulgare L. ssp. hirtum, thyme (Thymus vulgaris L. and wild thyme (Thymus serpyllum L. were tested in relation to their chemical composition. Total phenolic, flavonoid, catechin and anthocyanin content was determined by spectrophotometric methods. Oregano aqueous tea infusion had the highest amount of total phenols (12 500 mg/L gallic acid equivalent, GAE and flavonoids (9000 mg/L GAE. Identification of polyphenolic compounds in aqueous tea infusions by HPLC-PDA analysis showed a dominant presence of rosmarinic acid (in mg/g: 123.11 in oregano, 17.45 in thyme and 93.13 in wild thyme. Antioxidant activity of aqueous tea infusions was evaluated using four antioxidative methods (the b-carotene bleaching method (BCB, the 2,2’-diphenyl-1- -picrylhydrazyl (DPPH radical scavenging method, the thiobarbituric acid reactive species (TBARS assay and the induction period of lard oxidation (Rancimat assay. The results were compared with natural (ascorbic acid and a-tocopherol and synthetic antioxidants, butylated hydroxytoluene (BHT and butylated hydroxyanisole (BHA. Oregano aqueous tea infusion showed the strongest antioxidant activity using three methods (the b-carotene bleaching method, DPPH radical scavening method and Rancimat assay, while thyme and wild thyme showed weaker and relatively similar antioxidant activity.

  5. Dietary catechins and their potentially protective role in cardiovascular diseases and cancer

    NARCIS (Netherlands)

    Arts, I.C.W.

    2001-01-01

    Catechins are polyphenolic compounds in plant foods that belong to the family of flavonoids. Due to their strong antioxidant activity and their capacity to influence mammalian enzyme systems, catechins were hypothesized to affect risk of cardiovascular diseases and cancer in humans. After

  6. Caffeine use disorder: An item-response theory analysis of proposed DSM-5 criteria.

    Science.gov (United States)

    Ágoston, Csilla; Urbán, Róbert; Richman, Mara J; Demetrovics, Zsolt

    2018-06-01

    Caffeine is a common psychoactive substance with a documented addictive potential. Caffeine withdrawal has been included in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), but caffeine use disorder (CUD) is considered to be a condition for further study. The aim of the current study is (1) to test the psychometric properties of the Caffeine Use Disorder Questionnaire (CUDQ) by using a confirmatory factor analysis and an item response theory (IRT) approach, (2) to compare IRT models with varying numbers of parameters and models with or without caffeine consumption criteria, and (3) to examine if the total daily caffeine consumption and the use of different caffeinated products can predict the magnitude of CUD symptomatology. A cross-sectional study was conducted on an adult sample (N = 2259). Participants answered several questions regarding their caffeine consumption habits and completed the CUDQ, which incorporates the nine proposed criteria of the DSM-5 as well as one additional item regarding the suffering caused by the symptoms. Factor analyses demonstrated the unidimensionality of the CUDQ. The suffering criterion had the highest discriminative value at a higher degree of latent trait. The criterion of failure to fulfill obligations and social/interpersonal problems discriminate only at the higher value of CUD latent factor, while endorsement the consumption of more caffeine or longer than intended and craving criteria were discriminative at a lower level of CUD. Total daily caffeine intake was related to a higher level of CUD. Daily coffee, energy drink, and cola intake as dummy variables were associated with the presence of more CUD symptoms, while daily tea consumption as a dummy variable was related to less CUD symptoms. Regular smoking was associated with more CUD symptoms, which was explained by a larger caffeine consumption. The IRT approach helped to determine which CUD symptoms indicate more severity and have a greater

  7. Green tea and bone health

    Science.gov (United States)

    Osteoporosis is a major health problem in the elderly, particularly women. Epidemiological evidence has shown an association between tea consumption and the prevention of age-related bone loss in elderly women and men. Ingestion of green tea and green tea bioactive compounds may be beneficial in mit...

  8. Catechin is a phytototoxin and a pro-oxidant secreted from the roots of Centaurea stoebe.

    Science.gov (United States)

    Kaushik, Shail; Bais, Harsh P; Biedrzycki, Meredith L; Venkatachalam, Lakshmannan

    2010-09-01

    When applied to the roots of Arabidopsis thaliana, the phytotoxin (±)-catechin triggers a wave of reactive oxygen species (ROS), leading to a cascade of genome-wide changes in gene expression and, ultimately, death of the root system. Biochemical links describing the root secreted phytotoxin, (±)-catechin, represent one of most well studied systems to describe biochemically based negative plant-plant interactions, but of late have also sparked controversies on phytotoxicity and pro-oxidant behavior of (±)-catechin. The studies originating from two labs ( 1- 3) maintained that (±)-catechin is not at all phytotoxic but has strong antioxidant activity. The step-wise experiments performed and the highly correlative results reported in the present study clearly indicate that (±)-catechin indeed is phytotoxic against A. thaliana and Festuca idahoensis. Our results show that catechin dissolved in both organic and aqueous phase inflict phytotoxic activity against both A. thaliana and F. idahoensis. We show that the deviation in results highlighted by the two labs ( 1- 3) could be due to different media conditions and a group effect in catechin treated seedlings. We also determined the presence of catechin in the growth medium of C. stoebe to support the previous studies. One of the largest functional categories observed for catechin-responsive genes corresponded to gene families known to participate in cell death and oxidative stress. Our results showed that (±)-catechin treatment to A. thaliana plants resulted in activation of signature cell death genes such as accelerated cell death (acd2) and constitutively activated cell death 1 (cad1). Further, we confirmed our earlier observation of (±)-catechin induced ROS mediated phytotoxicity in A. thaliana. We also provide evidence that (±)-catechin induced ROS could be aggravated in the presence of divalent transition metals. These observations have significant impact on our understanding regarding catechin

  9. Catechin is a phytotoxin and a pro-oxidant secreted from the roots of Centaurea stoebe

    Science.gov (United States)

    Kaushik, Shail; Biedrzycki, Meredith L; Venkatachalam, Lakshmannan

    2010-01-01

    When applied to the roots of Arabidopsis thaliana, the phytotoxin (±)-catechin triggers a wave of reactive oxygen species (ROS), leading to a cascade of genome-wide changes in gene expression and, ultimately, death of the root system. Biochemical links describing the root secreted phytotoxin, (±)-catechin, represent one of most well studied systems to describe biochemically based negative plant-plant interactions, but of late have also sparked controversies on phytotoxicity and pro-oxidant behavior of (±)-catechin. The studies originating from two labs1–3 maintained that (±)-catechin is not at all phytotoxic but has strong antioxidant activity. The step-wise experiments performed and the highly correlative results reported in the present study clearly indicate that (±)-catechin indeed is phytotoxic against A. thaliana and Festuca idahoensis. Our results show that catechin dissolved in both organic and aqueous phase inflicts phytotoxic activity against both A. thaliana and F. idahoensis. We show that the deviation in results highlighted by the two labs1–3 could be due to different media conditions and a group effect in catechin treated seedlings. We also determined the presence of catechin in the growth medium of C. stoebe to support the previous studies. One of the largest functional categories observed for catechin-responsive genes corresponded to gene families known to participate in cell death and oxidative stress. Our results showed that (±)-catechin treatment to A. thaliana plants resulted in activation of signature cell death genes such as accelerated cell death (acd2) and constitutively activated cell death 1 (cad1). Further, we confirmed our earlier observation of (±)-catechin induced ROS mediated phytotoxicity in A. thaliana. We also provide evidence that (±)-catechin induced ROS could be aggravated in the presence of divalent transition metals. These observations have significant impact on our understanding regarding catechin phytotoxicity and

  10. Evaluating Dependence Criteria for Caffeine.

    Science.gov (United States)

    Striley, Catherine L W; Griffiths, Roland R; Cottler, Linda B

    2011-12-01

    Background: Although caffeine is the most widely used mood-altering drug in the world, few studies have operationalized and characterized Diagnostic and Statistical Manual IV (DSM-IV) substance dependence criteria applied to caffeine. Methods: As a part of a nosological study of substance use disorders funded by the National Institute on Drug Abuse, we assessed caffeine use and dependence symptoms among high school and college students, drug treatment patients, and pain clinic patients who reported caffeine use in the last 7 days and also reported use of alcohol, nicotine, or illicit drugs within the past year ( n =167). Results: Thirty-five percent met the criteria for dependence when all seven of the adopted DSM dependence criteria were used. Rates of endorsement of several of the most applicable diagnostic criteria were as follows: 26% withdrawal, 23% desire to cut down or control use, and 44% continued use despite harm. In addition, 34% endorsed craving, 26% said they needed caffeine to function, and 10% indicated that they talked to a physician or counselor about problems experienced with caffeine. There was a trend towards increased caffeine dependence among those dependent on nicotine or alcohol. Within a subgroup that had used caffeine, alcohol, and nicotine in the past year, 28% fulfilled criteria for caffeine dependence compared to 50% for alcohol and 80% for nicotine. Conclusion: The present study adds to a growing literature suggesting the reliability, validity, and clinical utility of the caffeine dependence diagnosis. Recognition of caffeine dependence in the DSM-V may be clinically useful.

  11. Caffeine intake during pregnancy and risk of problem behavior in 5- to 6-year-old children.

    Science.gov (United States)

    Loomans, Eva M; Hofland, Laura; van der Stelt, Odin; van der Wal, Marcel F; Koot, Hans M; Van den Bergh, Bea R H; Vrijkotte, Tanja G M

    2012-08-01

    Human studies that have investigated the association between caffeine intake during pregnancy and offspring's behavioral outcomes are scant and inconclusive. We prospectively investigated the association between maternal caffeine intake during pregnancy and children's problem behavior at age 5 to 6 years. Mediation by fetal growth restriction and gestational age as well as effect modification by the child's gender and maternal smoking was tested. In a community based multiethnic birth cohort, dietary caffeine intake (coffee, caffeinated tea, and cola) was measured (maternal self-report, n = 8202) around the 16th week of gestation. At age 5, children's overall problem behavior, emotional problems, conduct problems, hyperactivity/inattention problems, peer relationship problems, and prosocial behavior were rated by both mother and teacher (n = 3439) with the Strengths and Difficulties Questionnaire. Analyses were adjusted for maternal age, ethnicity, cohabitant status, education, smoking and alcohol consumption during pregnancy, child's gender, family size, and prenatal maternal anxiety. Caffeine intake was not associated with a higher risk for behavior problems or with suboptimal prosocial behavior. No evidence was found for mediation by fetal growth restriction or gestational age, nor for effect modification by the child's gender. Results did not provide evidence for developmental programming influences of intrauterine exposure to caffeine on offspring's problem behavior at age 5. Present results give no indication to advise pregnant women to reduce their caffeine intake to prevent behavior problems in their children.

  12. Effects of Exogenous Enzymatic Treatment During Processing on the Sensory Quality of Summer Tieguanyin Oolong Tea from the Chinese Anxi County

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    Xue-Bo Zhang

    2015-01-01

    Full Text Available In order to att enuate the bitt er taste and improve the aroma of the summer tieguanyin oolong tea from the Chinese Anxi county, the eff ects of processing treatment with exogenous laccase and α-galactosidase on tea sensory quality and related compounds were investigated. The solutio ns of laccase and/or α-galactosidase were sprayed on the tea leaves before the fi rst drying process. The sensory evaluation results showed that the sensory quality of the tea was signifi cantly enhanced with the enzymatic treatment. The combined application of laccase a t 8.25 and α- galactosidase at 22 U per kg of fresh tea shoots achieved the most satisfying sensory quality. Further analysis of fl avour-related constituents was carried out by HPLC and GC-MS. The HPLC analysis showed that the contents of catechins and total polyphen ols were reduced, compared to the untreated group, by 11.9 and 13.3 % respectively, and the total soluble sugars and water extract content were increased by 19.4 and 6.6 % respectively, aft er the treatment with both enzymes. The decrease of catechins and total polyphenols reduced the bitt erness and astringency of the summer tea, while the increase of total soluble sugars and water extract content improved the sweetness and mellow taste. The aromatic compound data from GC-MS showed that the total essential oil content in these tea samples co-treated with laccase and α-galactos idase increased significantly, in which aldehydes, alcohols, esters and alkenes increased by 23.28, 37.05, 20.10 and 38.99 %, respectively. Our data suggest that the exogenous enzymatic treatment can enhance the summer oolong tea quality, especially its taste and aroma.

  13. Effects of Exogenous Enzymatic Treatment During Processing on the Sensory Quality of Summer Tieguanyin Oolong Tea from the Chinese Anxi County.

    Science.gov (United States)

    Zhang, Xue-Bo; Du, Xian-Feng

    2015-06-01

    In order to attenuate the bitter taste and improve the aroma of the summer tieguanyin oolong tea from the Chinese Anxi county, the effects of processing treatment with exogenous laccase and α-galactosidase on tea sensory quality and related compounds were investigated. The solutions of laccase and/or α-galactosidase were sprayed on the tea leaves before the first drying process. The sensory evaluation results showed that the sensory quality of the tea was significantly enhanced with the enzymatic treatment. The combined application of laccase at 8.25 and α-galactosidase at 22 U per kg of fresh tea shoots achieved the most satisfying sensory quality. Further analysis of flavour-related constituents was carried out by HPLC and GC-MS. The HPLC analysis showed that the contents of catechins and total polyphenols were reduced, compared to the untreated group, by 11.9 and 13.3% respectively, and the total soluble sugars and water extract content were increased by 19.4 and 6.6% respectively, after the treatment with both enzymes. The decrease of catechins and total polyphenols reduced the bitterness and astringency of the summer tea, while the increase of total soluble sugars and water extract content improved the sweetness and mellow taste. The aromatic compound data from GC-MS showed that the total essential oil content in these tea samples co-treated with laccase and α-galactosidase increased significantly, in which aldehydes, alcohols, esters and alkenes increased by 23.28, 37.05, 20.10 and 38.99%, respectively. Our data suggest that the exogenous enzymatic treatment can enhance the summer oolong tea quality, especially its taste and aroma.

  14. Development of new antioxidant active packaging films based on ethylene vinyl alcohol copolymer (EVOH) and green tea extract.

    Science.gov (United States)

    Lopez de Dicastillo, Carol; Nerin, Cristina; Alfaro, Pilar; Catala, Ramon; Gavara, Rafael; Hernandez-Munoz, Pilar

    2011-07-27

    Ethylene vinyl alcohol copolymer (EVOH) films containing green tea extract were successfully produced by extrusion. The films were brown and translucent, and the addition of the extract increased the water and oxygen barrier at low relative humidity but increased the water sensitivity, the glass transition temperature, and the crystallinity of the films and improved their thermal resistance. An analysis by HPLC revealed that the antioxidant components of the extract suffered partial degradation during extrusion, reducing the content of catechin gallates and increasing the concentration of free gallic acid. Exposure of the films to various food simulants showed that the liquid simulants increased their capacity to reduce DPPH(•) and ABTS(•+) radicals. The release of green tea extract components into the simulant monitored by HPLC showed that all compounds present in the green tea extract were partially released, although the extent and kinetics of release were dependent on the type of food. In aqueous food simulants, gallic acid was the main antioxidant component released with partition coefficient values ca. 200. In 95% ethanol (fatty food simulant) the K value for gallic acid decreased to 8 and there was a substantial contribution of catechins (K in the 1000 range) to a greatly increased antioxidant efficiency. Kinetically, gallic acid was released more quickly than catechins, owing to its faster diffusivity in the polymer matrix as a consequence of its smaller molecular size, although the most relevant effect is the plasticization of the matrix by alcohol, increasing the diffusion coefficient >10-fold. Therefore, the materials here developed with the combination of antioxidant substances that constitute the green tea extract could be used in the design of antioxidant active packaging for all type of foods, from aqueous to fatty products, the compounds responsible for the protection being those with the higher compatibility with the packaged product.

  15. Validation and reproducibility of an Australian caffeine food frequency questionnaire.

    Science.gov (United States)

    Watson, E J; Kohler, M; Banks, S; Coates, A M

    2017-08-01

    The aim of this study was to measure validity and reproducibility of a caffeine food frequency questionnaire (C-FFQ) developed for the Australian population. The C-FFQ was designed to assess average daily caffeine consumption using four categories of food and beverages including; energy drinks; soft drinks/soda; coffee and tea and chocolate (food and drink). Participants completed a seven-day food diary immediately followed by the C-FFQ on two consecutive days. The questionnaire was first piloted in 20 adults, and then, a validity/reproducibility study was conducted (n = 90 adults). The C-FFQ showed moderate correlations (r = .60), fair agreement (mean difference 63 mg) and reasonable quintile rankings indicating fair to moderate agreement with the seven-day food diary. To test reproducibility, the C-FFQ was compared to itself and showed strong correlations (r = .90), good quintile rankings and strong kappa values (κ = 0.65), indicating strong reproducibility. The C-FFQ shows adequate validity and reproducibility and will aid researchers in Australia to quantify caffeine consumption.

  16. Inhibitory Effects of Green Tea and (-)-Epigallocatechin Gallate on Transport by OATP1B1, OATP1B3, OCT1, OCT2, MATE1, MATE2-K and P-Glycoprotein.

    Science.gov (United States)

    Knop, Jana; Misaka, Shingen; Singer, Katrin; Hoier, Eva; Müller, Fabian; Glaeser, Hartmut; König, Jörg; Fromm, Martin F

    2015-01-01

    Green tea catechins inhibit the function of organic anion transporting polypeptides (OATPs) that mediate the uptake of a diverse group of drugs and endogenous compounds into cells. The present study was aimed at investigating the effect of green tea and its most abundant catechin epigallocatechin gallate (EGCG) on the transport activity of several drug transporters expressed in enterocytes, hepatocytes and renal proximal tubular cells such as OATPs, organic cation transporters (OCTs), multidrug and toxin extrusion proteins (MATEs), and P-glycoprotein (P-gp). Uptake of the typical substrates metformin for OCTs and MATEs and bromosulphophthalein (BSP) and atorvastatin for OATPs was measured in the absence and presence of a commercially available green tea and EGCG. Transcellular transport of digoxin, a typical substrate of P-gp, was measured over 4 hours in the absence and presence of green tea or EGCG in Caco-2 cell monolayers. OCT1-, OCT2-, MATE1- and MATE2-K-mediated metformin uptake was significantly reduced in the presence of green tea and EGCG (P green tea [IC50 2.6% (v/v) and 0.39% (v/v), respectively]. Green tea also inhibited OATP1B1- and OATP1B3-mediated atorvastatin net uptake with IC50 values of 1.9% (v/v) and 1.0% (v/v), respectively. Basolateral to apical transport of digoxin was significantly decreased in the presence of green tea and EGCG. These findings indicate that green tea and EGCG inhibit multiple drug transporters in vitro. Further studies are necessary to investigate the effects of green tea on prototoypical substrates of these transporters in humans, in particular on substrates of hepatic uptake transporters (e.g. statins) as well as on P-glycoprotein substrates.

  17. Caffeine, Diabetes, Cognition, and Dementia

    NARCIS (Netherlands)

    Biessels, Geert Jan

    2010-01-01

    People with diabetes mellitus are at increased risk of cognitive dysfunction. This review explores the relation between caffeine intake, diabetes, cognition and dementia, focusing on type 2 diabetes (T2DM). Epidemiological studies on caffeine/coffee intake and T2DM risk are reviewed. Next, the

  18. Caffeine: sleep and daytime sleepiness.

    Science.gov (United States)

    Roehrs, Timothy; Roth, Thomas

    2008-04-01

    Caffeine is one of the most widely consumed psychoactive substances and it has profound effects on sleep and wake function. Laboratory studies have documented its sleep-disruptive effects. It clearly enhances alertness and performance in studies with explicit sleep deprivation, restriction, or circadian sleep schedule reversals. But, under conditions of habitual sleep the evidence indicates that caffeine, rather then enhancing performance, is merely restoring performance degraded by sleepiness. The sleepiness and degraded function may be due to basal sleep insufficiency, circadian sleep schedule reversals, rebound sleepiness, and/or a withdrawal syndrome after the acute, over-night, caffeine discontinuation typical of most studies. Studies have shown that caffeine dependence develops at relatively low daily doses and after short periods of regular daily use. Large sample and population-based studies indicate that regular daily dietary caffeine intake is associated with disturbed sleep and associated daytime sleepiness. Further, children and adolescents, while reporting lower daily, weight-corrected caffeine intake, similarly experience sleep disturbance and daytime sleepiness associated with their caffeine use. The risks to sleep and alertness of regular caffeine use are greatly underestimated by both the general population and physicians.

  19. Chernobyl radioactivity in Turkish tea

    International Nuclear Information System (INIS)

    Molzahn, D.; Tufail, M.; Patzelt, P.

    1990-01-01

    Radioactivity measurement of Turkish tea of 1986 crops is reported. The total cesium activity ranged from about 5500 Bq kg -1 up to 43600 Bq kg -1 . Some other fission products from Chernobyl could be detected in the tea samples, e.g., 95 Zr, 95 Nb, 103 Ru, 106 Ru, 110m Ag and 125 Sb. In addition, some activity values found in tea from USSR are given. The transfer rate of cesium from tea leaves to tea water was found to be about 74%. (author) 6 refs.; 1 fig.; 2 tabs

  20. Recent Advances in Volatiles of Teas

    Directory of Open Access Journals (Sweden)

    Xin-Qiang Zheng

    2016-03-01

    Full Text Available Volatile compounds are important components of tea aroma, a key attribute of sensory quality. The present review examines the formation of aromatic volatiles of various kinds of teas and factors influencing the formation of tea volatiles, including tea cultivar, growing environment and agronomic practices, processing method and storage of tea. The determination of tea volatiles and the relationship of active-aroma volatiles with the sensory qualities of tea are also discussed in the present paper.

  1. Effect of Dietary Cocoa Tea (Camellia ptilophylla Supplementation on High-Fat Diet-Induced Obesity, Hepatic Steatosis, and Hyperlipidemia in Mice

    Directory of Open Access Journals (Sweden)

    Xiao Rong Yang

    2013-01-01

    Full Text Available Recent studies suggested that green tea has the potential to protect against diet-induced obesity. The presence of caffeine within green tea has caused limitations. Cocoa tea (Camellia ptilophylla is a naturally decaffeinated tea plant. To determine whether cocoa tea supplementation results in an improvement in high-fat diet-induced obesity, hyperlipidemia and hepatic steatosis, and whether such effects would be comparable to those of green tea extract, we studied six groups of C57BL/6 mice that were fed with (1 normal chow (N; (2 high-fat diet (21% butterfat + 0.15% cholesterol, wt/wt (HF; (3 a high-fat diet supplemented with 2% green tea extract (HFLG; (4 a high-fat diet supplemented with 4% green tea extract (HFHG; (5 a high-fat diet supplemented with 2% cocoa tea extract (HFLC; and (6 a high-fat diet supplemented with 4% cocoa tea extract (HFHC. From the results, 2% and 4% dietary cocoa tea supplementation caused a dose-dependent decrease in (a body weight, (b fat pad mass, (c liver weight, (d total liver lipid, (e liver triglyceride and cholesterol, and (f plasma lipids (triglyceride and cholesterol. These data indicate that dietary cocoa tea, being naturally decaffeinated, has a beneficial effect on high-fat diet-induced obesity, hepatomegaly, hepatic steatosis, and elevated plasma lipid levels in mice, which are comparable to green tea. The present findings have provided the proof of concept that dietary cocoa tea might be of therapeutic value and could therefore provide a safer and cost effective option for patients with diet-induced metabolic syndrome.

  2. Additional benefit of higher dose green tea in lowering postprandial blood glucose

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    Rita Lahirin

    2015-07-01

    Full Text Available Background: Green tea contains catechins that have inhibitory effects on amylase, sucrase, and sodium-dependent glucose transporter (SGLT which result in lowering of postprandial blood glucose (PBG. This beneficial effect has been widely demonstrated using the usual dose (UD of green tea preparation. Our study was aimed to explore futher lowering of PBG using high dose (HD of green tea in healthy adolescents.Methods: 24 subjects received 100 mL infusion of either 0.67 or 3.33 grams of green tea with test meal. Fasting, PBG at 30, 60, 120 minutes were measured. Subjects were cross-overed after wash out. PBG and its incremental area under the curve (IAUC difference between groups were analyzed with paired T-test. Cathecin contents of tea were measured using high-performance liquid chromatography (HPLC.Results: The PBG of HD group was lower compared to UD (at 60 minutes =113.70 ± 13.20 vs 124.16 ± 8.17 mg/dL, p = 0.005; at 120 minutes = 88.95 ± 6.13 vs 105.25 ± 13.85 mg/dL, p < 0.001. The IAUC of HD was also found to be lower compared to UD (2055.0 vs 3411.9 min.mg/dL, p < 0.001.Conclusion: Additional benefit of lowering PBG can be achieved by using higher dose of green tea. This study recommends preparing higher dose of green tea drinks for better control of PBG.

  3. Green tea: a novel functional food for the oral health of older adults.

    Science.gov (United States)

    Gaur, Sumit; Agnihotri, Rupali

    2014-04-01

    Functional foods are foods with positive health effects that extend beyond their nutritional value. They affect the function of the body and help in the management of specific health conditions. Green tea, a time-honoured Chinese herb, might be regarded as a functional food because of its inherent anti-oxidant, anti-inflammatory, antimicrobial and antimutagenic properties. They are attributed to its reservoir of polyphenols, particularly the catechin, epigallocatechin-3-gallate. Owing to these beneficial actions, this traditional beverage was used in the management of chronic systemic diseases including cancer. Recently, it has been emphasized that the host immuno-inflammatory reactions destroy the oral tissues to a greater extent than the microbial activity alone. Green tea with its wide spectrum of activities could be a healthy alternative for controlling these damaging reactions seen in oral diseases, specifically, chronic periodontitis, dental caries and oral cancer, which are a common occurrence in the elderly population. © 2013 Japan Geriatrics Society.

  4. The Effect of Green Tea Extract on Reproductive Improvement in Estradiol Valerate-Induced Polycystic Ovarian Syndrome in Rat.

    Science.gov (United States)

    Ghafurniyan, Habibeh; Azarnia, Mahnaz; Nabiuni, Mohammad; Karimzadeh, Latifeh

    2015-01-01

    Polycystic ovary syndrome (PCOS) is a reproductive and metabolic disorder in which the level of oxidative elements in blood rises. Green tea is a potent antioxidant since it contains catechins. In this study, the effect of hydro-alcoholic green tea extract on PCOS rats was examined. For PCOS induction, 96 mature Wistar rats were given estradiol valerate. After 60 days, the rats were divided into four groups including PCOS group and three experimental groups, which were given 50, 100 and 200 mg/Kg BW green tea extract 10 days, intraperitoneally. The serum concentration level of FSH, LH, testosterone and insulin were measured using ELISA method, while the serum concentration level of glucose was measured using glucose oxidase methods. Insulin resistance was calculated using HOMA-IR formulation. The data were analyzed using the one-Way ANOVA method considering P<0/05 level of significance. There were a significant reduction in LH serum level, body and ovarian weight between the green tea extract treated-groups compare to PCOS. Moreover, a significant reduction in insulin resistance index was seen in the treatment groups related to PCOS. Histomorphometric studies also showed the significant changes in the number of follicles and theca layer thickness. These changes demonstrated a marked improvement in the symptoms of PCOS which may be due to green tea effects on oxidative stress pathways. Green tea can be considered as a potentially effective drug for treatment of PCOS, Insulin resistance and Type II diabetes.

  5. The Effects of Caffeine on Athletic Performance

    Science.gov (United States)

    McDaniel, Larry W.; McIntire, Kyle; Streitz, Carmyn; Jackson, Allen; Gaudet, Laura

    2010-01-01

    Athletes who use caffeine before exercising or competition may be upgrading themselves more than they realize. Caffeine is classified as a stimulant and is the most commonly used drug in the world. Caffeine has the same affects that amphetamines and cocaine have, just to a lesser degree. Caffeine crosses the membranes of all the body's tissues. It…

  6. Fluorine content of Fukien teas

    Energy Technology Data Exchange (ETDEWEB)

    Wang, T.H.; Lin, C.S.; Wu, C.; Liao, C.E.; Lin, H.Y.

    1949-01-01

    A study was made on the fluorine contents of Fukien teas and analytical results indicated the amount ranged from 5.7 to 35.5 mg. per 100 grams of dry tea. The high content of fluorine was found not to be due to contamination nor to the high fluorine content of the soil in which the tea plant was cultivated. Differences in the methods of manufacture had no effect on the fluorine content of the final products. Different varieties of tea plants have different powers to absorb fluorine from the soil. Of the two varieties of tea plants studied, Shui-Sen leaves possessed the lower fluorine content. Age of the tea leaves exerted an important influence on the fluorine content, the older leaves containing considerably more fluorine than the younger. The amount of fluorine that may be extracted in a two per cent infusion varies from 29.1 per cent for fresh leaves to 50.5 per cent for black tea. The process of roasting and rolling rendered the fluorine more soluble, hence the amount extracted increased in green tea. Fermentation further increased the extractability of the fluorine; thus the amount extracted was the highest in black tea, which was fermented, less in the semi-fermented oolong tea, and least in the unfermented green tea. The extractability of fluorine was also increased with age of the leaves.

  7. Tea Bowl: Imperfect Harmony

    OpenAIRE

    Mehring, Gretchen A; Greater Lafayette Museum of Art,

    1998-01-01

    These tea bowls, with their intimate scale and individual personalities, simultaneeously offer an apprectiation of the past and the contemporary. The subtle beauty of traditional-style bowls contrasts with the more exuberant contemporary idiom, raising an awareness of the role that art has, and can play, in everyday life.

  8. Tea Varrak / Ruth Alas

    Index Scriptorium Estoniae

    Alas, Ruth, 1960-2018

    2007-01-01

    Rahandusministeeriumi kantsler Tea Varrak iseloomustab ennast juhina, alluvate motiveerimine, ülevaade tavalisest tööpäevast, plaanid lähitulevikuks. Eluloolised andmed, haridus, täienduskoolitus, töökogemus. Kommenteerivad justiitsministeeriumi kantsler Jüri Pihl ja rahandusministeeriumi arendusjuht Alar Kolk

  9. Microbial diversity and component variation in Xiaguan Tuo Tea during pile fermentation.

    Science.gov (United States)

    Li, Haizhou; Li, Min; Yang, Xinrui; Gui, Xin; Chen, Guofeng; Chu, Jiuyun; He, Xingwang; Wang, Weitao; Han, Feng; Li, Ping

    2018-01-01

    Xiaguan Tuo Tea is largely consumed by the Chinese, but there is little research into the microbial diversity and component changes during the fermentation of this tea. In this study, we first used fluorescence in situ hybridization (FISH), next-generation sequencing (NGS) and chemical analysis methods to determine the microbial abundance and diversity and the chemical composition during fermentation. The FISH results showed that the total number of microorganisms ranges from 2.3×102 to 4.0×108 cells per gram of sample during fermentation and is mainly dominated by fungi. In the early fermentation stages, molds are dominant (0.6×102~2.8×106 cells/g, 0~35 d). However, in the late stages of fermentation, yeasts are dominant (3.6×104~9.6×106 cells/g, 35~56 d). The bacteria have little effect during the fermentation of tea (102~103 cells/g, tea was observed at day 35 of fermentation (Shannon-Weaver index: 1.195857), and lower diversity was observed on days 6 and 56 of fermentation (Shannon-Weaver index 0.860589 and 1.119106, respectively). During the microbial fermentation, compared to the unfermented tea, the tea polyphenol content decreased by 54%, and the caffeine content increased by 59%. Theanine and free amino acid contents were reduced during fermentation by 81.1 and 92.85%, respectively.

  10. A double-blind, placebo-controlled study evaluating the effects of caffeine and L-theanine both alone and in combination on cerebral blood flow, cognition and mood

    OpenAIRE

    Dodd, Fiona; Kennedy, David; Riby, Leigh; Haskell, Crystal

    2015-01-01

    Rationale -Evidence suggests interactive effects of the tea components caffeine and L-theanine on behaviour, yet no data exists exploring the impact of the two on cerebral blood flow (CBF).\\ud \\ud Objectives - The current placebo-controlled, double-blind, counterbalanced, crossover study examined the effects of caffeine and L-theanine on CBF and extended previous cognitive and mood findings by using lower doses than previous studies of a similar methodology, which more closely reflect the rat...

  11. Proteomic evaluation of myofibrillar carbonylation in chilled fish mince and its inhibition by catechin.

    Science.gov (United States)

    Pazos, Manuel; Maestre, Rodrigo; Gallardo, José M; Medina, Isabel

    2013-01-01

    The present study investigates the susceptibility of individual myofibrillar proteins from mackerel (Scomber scombrus) mince to undergo carbonylation reactions during chilled storage, and the antioxidant capacity of (+)-catechin to prevent oxidative processes of proteins. The carbonylation of each particular protein was quantified by combining the labelling of protein carbonyls by fluorescein-5-thiosemicarbazide (FTSC) with 1-D or 2-D gel electrophoresis. Alpha skeletal actin, glycogen phosphorylase, unnamed protein product (UNP) similar to enolase, pyruvate kinase, isoforms of creatine kinase, aldolase A and an isoform of glyceraldehyde 3-phosphate dehydrogenase (G3PDH) showed elevated oxidation in chilled non-supplemented mince. Myosin heavy chain (MHC) was not carbonylated in chilled muscle, but an extensive MHC degradation was observed in those samples. The supplementation of catechin reduced protein oxidation and lipid oxidation in a concentration-dependent manner: control>25>100≈200ppm. Therefore, the highest catechin concentrations (100 and 200ppm) exhibited the strongest antioxidant activity. Catechin (200ppm) reduced significantly carbonylation of protein spots identified as glycogen phosphorylase, pyruvate kinase muscle isozyme, isoforms of creatine kinase. Conversely, catechin was ineffective to inhibit the oxidation of actin and UNP similar to enolase. These results draw attention to the inefficiency of catechin to prevent actin oxidation, in contrast to the extremely high efficiency of catechin in inhibiting oxidation of lipids and other proteins. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Caffeine-containing energy drinks: beginning to address the gaps in what we know.

    Science.gov (United States)

    Sorkin, Barbara C; Coates, Paul M

    2014-09-01

    Energy drinks are relatively new to the United States but are the fastest growing segment of the beverage market. Humans have a long history of consuming caffeine in traditional beverages, such as cocoa, coffee, tea, and yerba maté, but 2 workshops held at the Institute of Medicine (http://www.iom.edu/Activities/Nutrition/PotentialHazardsCaffeineSupplements/2013-AUG-05.aspx) and the NIH (http://ods.od.nih.gov/News/EnergyDrinksWorkshop2013.aspx) in 2013 highlighted many critical gaps in understanding the biologic and behavioral effects of the mixtures of caffeine, vitamins, herbs, sugar or other sweeteners, and other ingredients that typify caffeine-containing energy drinks (CCEDs). For example, different surveys over the same 2010–2012 timeframe report discrepant prevalence of CCED use by teenagers, ranging from 10.3% in 13–17 y olds to >30% of those in grades 10 and 12. Understanding of functional interactions between CCED ingredients, drivers of use, and biologic and behavioral effects is limited. The 4 speakers in the Experimental Biology 2014 symposium titled “Energy Drinks: Current Knowledge and Critical Research Gaps” described recent progress by their groups in extending our understanding of prevalence of CCED use, sources of caffeine in the United States, drivers of CCED use, and behavioral correlations and effects of CCEDs, including effects on attractiveness of both alcoholic and non-alcoholic beverages.

  13. Smoking, caffeine, and nonsteroidal anti-inflammatory drugs in families with Parkinson disease.

    Science.gov (United States)

    Hancock, Dana B; Martin, Eden R; Stajich, Jeffrey M; Jewett, Rita; Stacy, Mark A; Scott, Burton L; Vance, Jeffery M; Scott, William K

    2007-04-01

    To assess associations between Parkinson disease (PD) and putatively protective factors-smoking, caffeine (coffee, tea, and soft drinks), and nonsteroidal anti-inflammatory drugs (aspirin, ibuprofen, and naproxen). Family-based case-control study. Academic medical center clinic. A total of 356 case subjects and 317 family controls who self-reported environmental exposures. Associations between PD and environmental measures (history, status, dosage, duration, and intensity) of smoking, coffee, caffeine, nonsteroidal anti-inflammatory drugs, and non-aspirin nonsteroidal anti-inflammatory drugs were examined using generalized estimating equations with an independent correlation matrix while controlling for age and sex. Individuals with PD were significantly less likely to report ever smoking (odds ratio = 0.56; 95% confidence interval, 0.41-0.78). Additional measures of smoking revealed significant inverse associations with PD (Pcoffee drinking was inversely associated with PD (test for trend P = .05). Increasing dosage (trend P = .009) and intensity (trend P = .01) of total caffeine consumption were also inversely associated, with high dosage presenting a significant inverse association for PD (odds ratio = 0.58; 95% confidence interval, 0.34-0.99). There were no significant associations between nonsteroidal anti-inflammatory drugs and PD. Inverse associations of smoking and caffeine were corroborated using families with PD, thus emphasizing smoking and caffeine as important covariates to consider in genetic studies of PD.

  14. Effects of caffeine on performance and mood depend on the level of caffeine abstinence.

    Science.gov (United States)

    Yeomans, Martin R; Ripley, Tamzin; Davies, Laura H; Rusted, Jennifer M; Rogers, Peter J

    2002-11-01

    Most studies of the effects of caffeine on performance have used regular caffeine consumers who are deprived at test. Thus the reported effects of caffeine could be explained through reversal of caffeine withdrawal. To test how preloading deprived caffeine consumers with 0, 1 or 2 mg/kg caffeine altered the subsequent ability of caffeine to modify mood and performance. Thirty moderate caffeine consumers were given a drink containing 0, 1 or 2 mg/kg caffeine at brea