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Caffeine L-Theanine

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https://www.readbyqxmd.com/read/29215606/cognitive-and-mood-effects-of-a-nutrient-enriched-breakfast-bar-in-healthy-adults-a-randomised-double-blind-placebo-controlled-parallel-groups-study
#1
David O Kennedy, Emma L Wightman, Joanne Forster, Julie Khan, Crystal F Haskell-Ramsay, Philippa A Jackson
OBJECTIVES: Few previous studies have assessed the effects of concomitant administration of multiple potentially psychoactive nutrients. METHODS: 95 healthy adult participants consumed either a nutrient enriched breakfast bar (containing α-Linolenic acid, l-tyrosine, l-theanine, vitamins, minerals and 21.5 mg of caffeine) or an isocaloric, macronutrient matched control bar for 56 days. Cognitive function and mood were assessed pre-dose and at 40- and 160-min post-dose on the 1st and 56th day of the intervention period...
December 7, 2017: Nutrients
https://www.readbyqxmd.com/read/29163391/colletotrichum-gloeosporioides-contaminated-tea-infusion-blocks-lipids-reduction-and-induces-kidney-damage-in-mice
#2
Jin Li, Kang Sun, Qingping Ma, Jin Chen, Le Wang, Dingjun Yang, Xuan Chen, Xinghui Li
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...
2017: Frontiers in Microbiology
https://www.readbyqxmd.com/read/28938517/green-tea-camellia-sinensis-and-l-theanine-medicinal-values-and-beneficial-applications-in-humans-a-comprehensive-review
#3
REVIEW
Muhammad Saeed, Muhammad Naveed, Muhammad Arif, Mohib Ullah Kakar, Robina Manzoor, Mohamed Ezzat Abd El-Hack, Mahmoud Alagawany, Ruchi Tiwari, Rekha Khandia, Ashok Munjal, Kumaragurubaran Karthik, Kuldeep Dhama, Hafiz M N Iqbal, Maryam Dadar, Chao Sun
Green tea (Camellia sinensis) is a famous herb, and its extract has been extensively used in traditional Chinese medicinal system. In this context, several studies have revealed its health benefits and medicinal potentialities for several ailments. With ever increasing scientific knowledge, search for safer, potential and novel type of health-related supplements quest, scientists are re-directing their research interests to explore natural resources i.e. medicinal herbs/plant derived compounds. Green tea consumption has gained a special attention and popularity in the modern era of changing lifestyle...
November 2017: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/28899506/green-tea-effects-on-cognition-mood-and-human-brain-function-a-systematic-review
#4
REVIEW
Edele Mancini, Christoph Beglinger, Jürgen Drewe, Davide Zanchi, Undine E Lang, Stefan Borgwardt
BACKGROUND: Green tea (Camellia sinensis) is a beverage consumed for thousands of years. Numerous claims about the benefits of its consumption were stated and investigated. As green tea is experiencing a surge in popularity in Western culture and as millions of people all over the world drink it every day, it is relevant to understand its effects on the human brain. PURPOSE: To assess the current state of knowledge in the literature regarding the effects of green tea or green tea extracts, l-theanine and epigallocatechin gallate both components of green tea-on general neuropsychology, on the sub-category cognition and on brain functions in humans...
October 15, 2017: Phytomedicine: International Journal of Phytotherapy and Phytopharmacology
https://www.readbyqxmd.com/read/28852881/itraq-based-proteomics-monitors-the-withering-dynamics-in-postharvest-leaves-of-tea-plant-camellia-sinensis
#5
Zhi-Jun Wu, Hong-Yu Ma, Jing Zhuang
Tea plant [Camellia sinensis (L.) O. Kuntze] is a typical leaf-type beverage crop. Many secondary metabolites, such as tea polyphenols, theanine, and caffeine that accumulated in tea leaves are beneficial to human health. The fresh leaves of tea plant are harvested and timely processed into tea products with different flavors. The withering of fresh tea leaves is the first step in tea processing and directly affects tea color, taste, and fragrance. To understand the molecular mechanism that influences tea quality during withering, we investigated the dynamic changes in the proteome of postharvest tea leaves in four withering stages (0, 1, 4, and 12 h treatments)...
August 29, 2017: Molecular Genetics and Genomics: MGG
https://www.readbyqxmd.com/read/28801632/stimulation-in-primary-and-secondary-metabolism-by-elevated-carbon-dioxide-alters-green-tea-quality-in-camellia-sinensis-l
#6
Xin Li, Lan Zhang, Golam Jalal Ahammed, Zhi-Xin Li, Ji-Peng Wei, Chen Shen, Peng Yan, Li-Ping Zhang, Wen-Yan Han
Rising CO2 concentration, a driving force of climate change, is impacting global food security by affecting plant physiology. Nevertheless, the effects of elevated CO2 on primary and secondary metabolism in tea plants (Camellia sinensis L.) still remain largely unknown. Here we showed that exposure of tea plants to elevated CO2 (800 µmol mol(-1) for 24 d) remarkably improved both photosynthesis and respiration in tea leaves. Furthermore, elevated CO2 increased the concentrations of soluble sugar, starch and total carbon, but decreased the total nitrogen concentration, resulting in an increased carbon to nitrogen ratio in tea leaves...
August 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28640307/healthy-properties-of-green-and-white-teas-an-update
#7
S Pastoriza, M Mesías, C Cabrera, J A Rufián-Henares
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...
August 1, 2017: Food & Function
https://www.readbyqxmd.com/read/28056735/effect-of-green-tea-phytochemicals-on-mood-and-cognition
#8
Christina Dietz, Matthijs Dekker
BACKGROUND: 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...
January 5, 2017: Current Pharmaceutical Design
https://www.readbyqxmd.com/read/28044450/caffeine-and-theanine-exert-opposite-effects-on-attention-under-emotional-arousal
#9
Grace E Giles, Caroline R Mahoney, Tad T Brunyé, Holly A Taylor, Robin B Kanarek
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...
January 2017: Canadian Journal of Physiology and Pharmacology
https://www.readbyqxmd.com/read/27625668/brassinosteroids-improve-quality-of-summer-tea-camellia-sinensis-l-by-balancing-biosynthesis-of-polyphenols-and-amino-acids
#10
Xin Li, Golam J Ahammed, Zhi-Xin Li, Lan Zhang, Ji-Peng Wei, Chen Shen, Peng Yan, Li-Ping Zhang, Wen-Yan Han
Summer grown green tea is less popular due to bitterness and high astringency, which are attributed to high levels of tea polyphenols (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...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27407065/the-identification-and-evaluation-of-two-different-color-variations-of-tea
#11
Yuchen Li, Changsong Chen, Yusheng Li, Zhaotang Ding, Jiazhi Shen, Yu Wang, Lei Zhao, Meng Xu
BACKGROUND: The tea plant, Camellia sinensis (L.) O. Kuntz, is a perennial woody plant widely cultivated for the production of a popular non-alcoholic beverage. To rapidly identify and evaluate two different color tea varieties (yellowish and purplish), the main phenotypic traits and quality components were tested in the present study. The metabolic profiles of tea shoots and leaves were also analyzed using liquid chromatography-tandem mass spectrometry. RESULTS: The yellowish variation had a higher active level with respect to metabolism of catechins, and the contents of luteolin and kaempferol 3-α-d-glucoside were much higher compared to in the other variations...
December 2016: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/27066035/transcriptomic-analysis-reveals-the-molecular-mechanisms-of-drought-stress-induced-decreases-in-camellia-sinensis-leaf-quality
#12
Weidong Wang, Huahong Xin, Mingle Wang, Qingping Ma, Le Wang, Najeeb A Kaleri, Yuhua Wang, Xinghui Li
The tea plant [Camellia sinensis (L.) O. Kuntze] is an important commercial crop rich in bioactive ingredients, especially catechins, caffeine, theanine and other free amino acids, which the quality of tea leaves depends on. Drought is the most important environmental stress affecting the yield and quality of this plant. In this study, the effects of drought stress on the phenotype, physiological characteristics and major bioactive ingredients accumulation of C. sinensis leaves were examined, and the results indicated that drought stress resulted in dehydration and wilt of the leaves, and significant decrease in the total polyphenols and free amino acids and increase in the total flavonoids...
2016: Frontiers in Plant Science
https://www.readbyqxmd.com/read/27019564/theanine-and-caffeine-content-of-infusions-prepared-from-commercial-tea-samples
#13
Klára Boros, Nikoletta Jedlinszki, Dezső Csupor
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 caffeine and theanine content and processing methods...
January 2016: Pharmacognosy Magazine
https://www.readbyqxmd.com/read/26902467/the-single-and-synergistic-effects-of-the-major-tea-components-caffeine-epigallocatechin-3-gallate-and-l-theanine-on-rat-sperm-viability
#14
Tânia R Dias, Marco G Alves, Susana Casal, Branca M Silva, Pedro F Oliveira
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)...
March 2016: Food & Function
https://www.readbyqxmd.com/read/26869148/acute-effects-of-theanine-caffeine-and-theanine-caffeine-combination-on-attention
#15
Chanaka N Kahathuduwa, Tharaka L Dassanayake, A M Tissa Amarakoon, Vajira S Weerasinghe
OBJECTIVE: 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. DESIGN: 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...
February 12, 2016: Nutritional Neuroscience
https://www.readbyqxmd.com/read/26687755/bioactive-compounds-in-green-tea-leaves-attenuate-the-injury-of-retinal-ganglion-rgc-5-cells-induced-by-h2o2-and-ultraviolet-radiation
#16
Jianchang Jin, Hao Ying, Meirong Huang, Qizhen Du
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...
November 2015: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/26192072/l-theanine-unique-amino-acid-of-tea-and-its-metabolism-health-effects-and-safety
#17
REVIEW
Duygu Türközü, Nevin Şanlier
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...
May 24, 2017: Critical Reviews in Food Science and Nutrition
https://www.readbyqxmd.com/read/26109792/quantification-of-total-polyphenols-catechin-caffeine-l-theanine-determination-of-antioxidant-activity-and-effect-on-antileishmanial-drugs-of-ethiopian-tea-leaves-extracts
#18
Alemu Tadesse, Ariaya Hymete, Adnan A Bekhit, Salahuddin Farooq Mohammed
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...
June 2015: Pharmacognosy Research
https://www.readbyqxmd.com/read/26058139/occurrence-and-de-novo-biosynthesis-of-caffeine-and-theanine-in-seedlings-of-tea-camellia-sinensis
#19
Wei-Wei Deng, Hiroshi Ashihara
Caffeine (1,3,7-trimethyl xanthine) and theanine (γ-glutamyl-L-ethylamide) are the major nitrogen-containing secondary metabolites in tea leaves. The aim of the present study was to elucidate the relative concentration and amounts of these compounds and the de novo biosynthetic activity in different parts of tea seedlings grown for 27-, 106- and 205 days. The results indicated that caffeine and its biosynthetic activity occur only in leaves and stems, while theanine is distributed in all organs, including roots...
May 2015: Natural Product Communications
https://www.readbyqxmd.com/read/25977676/can-tea-consumption-be-a-safe-and-effective-therapy-against-diabetes-mellitus-induced-neurodegeneration
#20
Ana R Nunes, Marco G Alves, Paula I Moreira, Pedro F Oliveira, Branca M Silva
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...
December 2014: Current Neuropharmacology
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