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https://www.readbyqxmd.com/read/28520776/proteomic-analysis-of-tea-plants-camellia-sinensis-with-purple-young-shoots-during-leaf-development
#1
Qiongqiong Zhou, Zhidan Chen, Jinwook Lee, Xinghui Li, Weijiang Sun
Tea products made from purple leaves are highly preferred by consumers due to the health benefits. This study developed a proteome reference map related to color changes during leaf growth in tea (Camellia sinensis) plant with purple young shoots using two-dimensional electrophoresis (2-DE). Forty-six differentially expressed proteins were detected in the gel and successfully identified by using MALDI-TOF/TOF-MS. The pronounced changes in the proteomic profile between tender purple leaves (TPL) and mature green leaves (MGL) included: 1) the lower activity of proteins associated with CO2 assimilation, energy metabolism and photo flux efficiency and higher content of anthocyanins in TPL than those in MGL may protect tender leaves against photo-damage; 2) the higher abundance of chalcone synthase (CHS), chalcone isomerase (CHI) and flavonol synthase (FLS) likely contributes to the synthesis of anthocyanins, catechins and flavonols in TPL tissues; 3) higher abundance of stress response proteins, such as glutathione S-transferases (GST) and phospholipid hydroperoxide glutathione peroxidase (PHGPx), could enhance the tolerance of TPL tissues to adverse condition in; and 4) the increased abundance of proteins related to protein synthesis, nucleic acids and cell wall proteins should be beneficial for the proliferation and expansion of leaf cell in TPL tissues...
2017: PloS One
https://www.readbyqxmd.com/read/28515380/highly-selective-and-considerable-subcritical-butane-extraction-to-separate-abamectin-in-green-tea
#2
Yating Zhang, Lingbiao Gu, Fei Wang, Lingjun Kong, Huili Pang, Guangyong Qin
We specially carried out the subcritical butane extraction to separate abamectin from tea leaves. Four parameters, such as extraction temperature, extraction time, number of extraction cycles, and solid-liquid ratio were studied and optimized through the response surface methodology with design matrix developed by Box-Behnken. Seventeen experiments with three various factors and three variable levels were employed to investigate the effect of these parameters on the extraction of abamectin. Besides, catechins, theanine, caffeine, and aroma components were determined by both high-performance liquid chromatography and gas chromatography-mass spectrometry to evaluate the tea quality before and after the extraction...
May 17, 2017: Journal of Oleo Science
https://www.readbyqxmd.com/read/28511005/characterization-of-l-theanine-excitatory-actions-on-hippocampal-neurons-towards-the-generation-of-novel-n-methyl-d-aspartate-receptor-modulators-based-on-its-backbone
#3
Fatiha Sebih, Matthieu Rousset, Salima Bellahouel, Marc Rolland, Marie Celeste de Jesus Ferreira, Janique Guiramand, Catherine Cohen-Solal, Gérard Barbanel, Thierry Cens, Mohammed Abouazza, Adrien Tassou, Maud Gratuze, Céline Meunier, Pierre Charnet, Michel Vignes, Valérie Rolland
L-Theanine (or L-γ-N-ethyl-glutamine) is the major amino acid found in Camellia sinensis. It has received much attention because of its pleiotropic physiological and pharmacological activities leading to health benefits in humans, especially. We describe here a new, easy, efficient and environmentally-friendly chemical synthesis of L-Theanine and L-γ-N-propyl-Gln and their corresponding D isomers. L-Theanine, and its derivatives obtained so far, exhibited partial co-agonistic action at N-methyl-D-aspartate (NMDA) receptors, with no detectable agonist effect at other glutamate receptors, on cultured hippocampal neurons...
May 16, 2017: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/28473262/the-tea-tree-genome-provides-insights-into-tea-flavor-and-independent-evolution-of-caffeine-biosynthesis
#4
En-Hua Xia, Hai-Bin Zhang, Jun Sheng, Kui Li, Qun-Jie Zhang, Changhoon Kim, Yun Zhang, Yuan Liu, Ting Zhu, Wei Li, Hui Huang, Yan Tong, Hong Nan, Cong Shi, Chao Shi, Jian-Jun Jiang, Shu-Yan Mao, Jun-Ying Jiao, Dan Zhang, Yuan Zhao, You-Jie Zhao, Li-Ping Zhang, Yun-Long Liu, Ben-Ying Liu, Yue Yu, Sheng-Fu Shao, De-Jiang Ni, Evan E Eichler, Li-Zhi Gao
Tea is the world's oldest and most popular caffeine-containing beverage with immense economic, medicinal, and cultural importance. Here, we present the first high-quality nucleotide sequence of the repeat-rich (80.9%), 3.02-Gb genome of the cultivated tea tree Camellia sinensis. We show that an extraordinarily large genome size of tea tree is resulted from the slow, steady, and long-term amplification of a few LTR retrotransposon families. In addition to a recent whole-genome duplication event, lineage-specific expansions of genes associated with flavonoid metabolic biosynthesis were discovered, which enhance catechin production, terpene enzyme activation, and stress tolerance, important features for tea flavor and adaptation...
April 29, 2017: Molecular Plant
https://www.readbyqxmd.com/read/28439281/l-theanine-content-and-related-gene-expression-novel-insights-into-theanine-biosynthesis-and-hydrolysis-among-different-tea-plant-camellia-sinensis-l-tissues-and-cultivars
#5
Zhi-Wei Liu, Zhi-Jun Wu, Hui Li, Yong-Xin Wang, Jing Zhuang
L-Theanine content has tissues and cultivars specificity in tea plant (Camellia sinensis L.), the correlations of theanine metabolic related genes expression profiles with theanine contents were explored in this study. L-theanine contents in the bud and 1st leaf, 2nd leaf, 3rd leaf, old leaf, stem, and lateral root were determined by HPLC from three C. sinensis cultivars, namely 'Huangjinya', 'Anjibaicha', and 'Yingshuang', respectively. The theanine contents in leaves and root of 'Huangjinya' were the highest, followed by 'Anjibaicha', and 'Yingshuang'...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28429900/theanine-the-unique-amino-acid-in-the-tea-plant-as-an-oral-hepatoprotective-agent
#6
Dongxu Wang, Qiang Gao, Taotao Wang, Frank Qian, Yijun Wang
For thousands of years, humans have consumed tea made from leaves of Camellia sinensis, first as a medicinal herb and then as a widely popular beverage. In the past 10 years, theanine, a tea-derived, unique, nonproteinic amino acid, has been extensively studied for its health benefits. Recently, multiple lines of evidence have proven its beneficial effects on hepatic and immune functions. One possible mechanism for its biological activity involves the downregulation of the inflammatory response through the induction of nitric oxide production and glutathione synthesis...
May 2017: Asia Pacific Journal of Clinical Nutrition
https://www.readbyqxmd.com/read/28416871/effect-of-water-quality-on-the-main-components-in-fuding-white-tea-infusions
#7
Haihua Zhang, Yulan Jiang, Yangjun Lv, Junxian Pan, Yuwei Duan, Yunyun Huang, Yuejin Zhu, Shikang Zhang, Kunkun Geng
The aim of this study was to investigate the effect of water quality on the main components in Fuding white tea infusions, including catechins, caffeine, theanine and free amino acids. Pure, tap and spring water were tested, and water quality was found to have a distinct effect on the main compounds extracted. Pure water, which was weakly acidic and low in dissolved ions, achieved the highest catechin content, whereas caffeine and theanine, and amino acids, were higher in infusions made with spring and tap water, respectively...
April 2017: Journal of Food Science and Technology
https://www.readbyqxmd.com/read/28412808/spontaneously-assembled-nano-aggregates-in-clear-green-tea-infusions-from-camellia-ptilophylla-and-camellia-sinensis
#8
Xiaorong Lin, Xiong Gao, Zhongzheng Chen, Yuanyuan Zhang, Wei Luo, Xiaofei Li, Bin Li
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...
April 26, 2017: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/28391425/safety-tolerability-and-efficacy-of-drugs-for-treating-behavioural-insomnia-in-children-with-attention-deficit-hyperactivity-disorder-a-systematic-review-with-methodological-quality-assessment
#9
REVIEW
Shweta Anand, Henry Tong, Frank M C Besag, Esther W Chan, Samuele Cortese, Ian C K Wong
OBJECTIVE: A large proportion of paediatric patients with attention-deficit/hyperactivity disorder (ADHD) have associated sleep problems which not only affect the child's wellbeing but also impact family functioning. Management of sleep problems is consequently an important aspect of overall ADHD management in paediatric patients. Although some drugs are being used off-label for the management of paediatric insomnia, there is scant clinical evidence supporting their use. Our aim was to identify and assess the quality of published studies reporting the safety, tolerability and efficacy of drugs used for treating behavioural insomnia in children with ADHD...
June 2017: Paediatric Drugs
https://www.readbyqxmd.com/read/28365292/evolving-transpeptidase-and-hydrolytic-variants-of-%C3%AE-glutamyl-transpeptidase-from-bacillus-licheniformis-by-targeted-mutations-of-conserved-residue-arg109-and-their-biotechnological-relevance
#10
Shruti Bindal, Sujata Sharma, Tej P Singh, Rani Gupta
γ-Glutamyl transpeptidase (GGT) catalyzes the transfer of the γ-glutamyl moiety from donor compounds such as l-glutamine (Gln) and glutathione (GSH) to an acceptor. During the biosynthesis of various γ-glutamyl-containing compounds using GGT enzyme, auto-transpeptidation reaction leads to the formation of unwanted byproducts. Therefore, in order to alter the auto-transpeptidase activity of the GGT enzyme, the binding affinity of Gln should be modified. Structural studies of the Bacillus licheniformis GGT (BlGT) complexed with the glutamic acid has shown that glutamic acid has strong ionic interactions through its α-carboxlic group with the guanidine moiety of Arg109...
March 30, 2017: Journal of Biotechnology
https://www.readbyqxmd.com/read/28358319/effective-subcritical-butane-extraction-of-bifenthrin-residue-in-black-tea
#11
Yating Zhang, Lingbiao Gu, Fei Wang, Lingjun Kong, Guangyong Qin
As a natural and healthy beverage, tea is widely enjoyed; however, the pesticide residues in tea leaves affect the quality and food safety. To develop a highly selective and efficient method for the facile removal of pesticide residues, the subcritical butane extraction (SBE) technique was employed, and three variables involving temperature, time and extraction cycles were studied. The optimum SBE conditions were found to be as follows: extraction temperature 45 °C, extraction time 30 min, number of extraction cycles 1, and in such a condition that the extraction efficiency reached as high as 92%...
March 30, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28332598/metabolic-flux-redirection-and-transcriptomic-reprogramming-in-the-albino-tea-cultivar-yu-jin-xiang-with-an-emphasis-on-catechin-production
#12
Guo-Feng Liu, Zhuo-Xiao Han, Lin Feng, Li-Ping Gao, Ming-Jun Gao, Margaret Y Gruber, Zhao-Liang Zhang, Tao Xia, Xiao-Chun Wan, Shu Wei
In this study, shade-induced conversion from a young pale/yellow leaf phenotype to a green leaf phenotype was studied using metabolic and transcriptomic profiling and the albino cultivar 'Yu-Jin-Xiang' ('YJX') of Camellia sinensis for a better understanding of mechanisms underlying the phenotype shift and the altered catechin and theanine production. Shaded leaf greening resulted from an increase in leaf chlorophyll and carotenoid abundance and chloroplast development. A total of 1,196 differentially expressed genes (DEGs) were identified between the 'YJX' pale and shaded green leaves, and these DEGs affected 'chloroplast organization' and 'response to high light' besides many other biological processes and pathways...
March 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28321230/integrated-transcriptome-and-metabolic-analyses-reveals-novel-insights-into-free-amino-acid-metabolism-in-huangjinya-tea-cultivar
#13
Qunfeng Zhang, Meiya Liu, Jianyun Ruan
The chlorotic tea variety Huangjinya, a natural mutant, contains enhanced levels of free amino acids in its leaves, which improves the drinking quality of its brewed tea. Consequently, this chlorotic mutant has a higher economic value than the non-chlorotic varieties. However, the molecular mechanisms behind the increased levels of free amino acids in this mutant are mostly unknown, as are the possible effects of this mutation on the overall metabolome and biosynthetic pathways in tea leaves. To gain further insight into the effects of chlorosis on the global metabolome and biosynthetic pathways in this mutant, Huangjinya plants were grown under normal and reduced sunlight, resulting in chlorotic and non-chlorotic leaves, respectively; their leaves were analyzed using transcriptomics as well as targeted and untargeted metabolomics...
2017: Frontiers in Plant Science
https://www.readbyqxmd.com/read/28315395/acute-intravenous-administration-of-dietary-constituent-theanine-suppresses-noxious-neuronal-transmission-of-trigeminal-spinal-nucleus-caudalis-in-rats
#14
Shiori Takehana, Yoshiko Kubota, Nobuo Uotsu, Kei Yui, Yoshihito Shimazu, Mamoru Takeda
Theanine is a non-dietary amino acid linked to the modulation of synaptic transmission in the central nervous system, although the acute effects of theanine in vivo, particularly on nociceptive transmission in the trigeminal system, remain to be determined. The present study investigated whether acute intravenous theanine administration to rats attenuates the excitability of wide dynamic range (WDR) spinal trigeminal nucleus caudalis (SpVc) neurons in response to nociceptive and non-nociceptive mechanical stimulation in vivo...
March 15, 2017: Brain Research Bulletin
https://www.readbyqxmd.com/read/28056735/effect-of-green-tea-phytochemicals-on-mood-and-cognition
#15
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
#16
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/27908701/inhibitory-effects-of-l-theanine-on-airway-inflammation-in-ovalbumin-induced-allergic-asthma
#17
Yong Pil Hwang, Sun Woo Jin, Jae Ho Choi, Chul Yung Choi, Hyung Gyun Kim, Se Jong Kim, Yongan Kim, Kyung Jin Lee, Young Chul Chung, Hye Gwang Jeong
l-theanine, a water-soluble amino acid isolated from green tea (Camellia sinensis), has anti-inflammatory activity, antioxidative properties, and hepatoprotective effects. However, the anti-allergic effect of l-theanine and its underlying molecular mechanisms have not been elucidated. In this study, we investigated the protective effects of l-theanine on asthmatic responses, particularly airway inflammation and oxidative stress modulation in an ovalbumin (OVA)-induced murine model of asthma. Treatment with l-theanine dramatically attenuated the extensive trafficking of inflammatory cells into bronchoalveolar lavage fluid (BALF)...
January 2017: Food and Chemical Toxicology
https://www.readbyqxmd.com/read/27872968/new-functions-and-potential-applications-of-amino-acids
#18
Hisayuki Uneyama, Hisamine Kobayashi, Naoto Tonouchi
Currently, several types of amino acids are being produced and used worldwide. Nevertheless, several new functions of amino acids have been recently discovered that could result in other applications. For example, oral stimulation by glutamate triggers the cephalic phase response to prepare for food digestion. Further, the stomach and intestines have specific glutamate-recognizing systems in their epithelial mucosa. Regarding clinical applications, addition of monosodium glutamate to the medicinal diet has been shown to markedly enhance gastric secretion in a vagus-dependent manner...
November 22, 2016: Advances in Biochemical Engineering/biotechnology
https://www.readbyqxmd.com/read/27855934/variation-of-theanine-phenolic-and-methylxanthine-compounds-in-21-cultivars-of-camellia-sinensis-harvested-in-different-seasons
#19
Rui Fang, Sally P Redfern, Don Kirkup, Elaine A Porter, Geoffrey C Kite, Leon A Terry, Mark J Berry, Monique S J Simmonds
This is the first study to use chemometric methods to differentiate among 21 cultivars of Camellia sinensis from China and between leaves harvested at different times of the year using 30 compounds implicated in the taste and quality of tea. Unique patterns of catechin derivatives were observed among cultivars and across harvest seasons. C. sinensis var. pubilimba (You 510) differed from the cultivars of C. sinensis var. sinensis, with higher levels of theobromine, (+)-catechin, gallocatechin, gallocatechin gallate and theasinensin B, and lower levels of (-)-epicatechin, (-)-epigallocatechin (EGC) and (-)-epigallocatechin gallate (EGCG), respectively...
April 1, 2017: Food Chemistry
https://www.readbyqxmd.com/read/27809221/tea-polysaccharides-and-their-bioactivities
#20
REVIEW
Ling-Ling Du, Qiu-Yue Fu, Li-Ping Xiang, Xin-Qiang Zheng, Jian-Liang Lu, Jian-Hui Ye, Qing-Sheng Li, Curt Anthony Polito, Yue-Rong Liang
Tea (Camellia sinensis) is a beverage beneficial to health and is also a source for extracting bioactive components such as theanine, tea polyphenols (TPP) and tea polysaccharides (TPS). TPS is a group of heteropolysaccharides bound with proteins. There is evidence showing that TPS not only improves immunity but also has various bioactivities, such as antioxidant, antitumor, antihyperglycemia, and anti-inflammation. However, inconsistent results concerning chemical composition and bioactivity of TPS have been published in recent years...
October 30, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
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