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Tea polyphenols

Ji-Yuan Liang, Jun-Yun Wu, Ming-Yeh Yang, Anren Hu, Liang-Yü Chen
Polyphenols are associated with a wide range of physiological properties. Catechin is a flavan-3-ol with five phenolic hydroxyl groups. After blue light illumination, the transparent solution of catechin became yellowish. The effects of visible light illumination (400-800nm) were investigated on molecular structures and antioxidant capacities of catechin. Under the neutral or alkaline aqueous with the illumination of blue light, the photolysis and polymerization of catechin were observed in this study. A chromogenic catechin dimer was separated and identified as a proanthocyanidin by the chromatographic technique and mass spectrometry...
October 19, 2016: Journal of Photochemistry and Photobiology. B, Biology
Yohei Shirakami, Hiroyasu Sakai, Takahiro Kochi, Mitsuru Seishima, Masahito Shimizu
The mechanisms of action of polyphenols have attracted much attention. Catechins are generally known as tea polyphenols. Researchers have extensively investigated the molecular mechanisms of these substances, especially (-)-epigallocatechin gallate of green tea catechin, and have provided new insights in the prevention and therapy for chronic diseases. This chapter summarizes catechins and their effects on chronic diseases, including metabolic syndromes, cardiovascular diseases, neurodegenerative diseases, and cancer, focusing on the effects of green tea catechins...
2016: Advances in Experimental Medicine and Biology
Dong Bok Jeon, Young Shin Hong, Ga Hyun Lee, Yu Min Park, Cheong Mi Lee, Eun Yeong Nho, Ji Yeon Choi, Nargis Jamila, Naeem Khan, Kyong Su Kim
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)...
March 15, 2017: Food Chemistry
Naga Pavan Kumar Chevala, Naga Thirumalesh Chevala, Kirubakaran Dhanakodi, Rama Rao Nadendla, Chandrashekara Krishnappa Nagarathna
BACKGROUND: Tea is an economic important crop with high medicinal value due to rich polyphenols content. In the present research we studied the accumulation of polyphenols of in vitro regenerated callus from anthers. OBJECTIVE: Callus induction of tea anthers and in vitro accumulation of phenolic compounds from the anther-derived callus. MATERIALS AND METHODS: Standardization of callus induction for tea anthers. In vitro generated callus was screened for in vivo accumulation of catechins and its isomers were screened by FC reagent staining technique...
July 2016: Pharmacognosy Magazine
Teruki Aizawa, Ayaka Yamamoto, Tomoya Ueno
Theaflavins are reddish-colored polyphenols in black tea. To test the efficacy of theaflavin administration on body fat and muscle, we performed a randomized, double-blind, placebo-controlled study and investigated the effect of theaflavins administration on the body composition using of healthy subjects. In this study, 30 male and female Japanese were enrolled and participants were randomly allocated to receive placebo, theaflavin (50 or 100 mg/day), or catechin (400 mg/ml) for 10 weeks. The effects were evaluated using body weight, body fat percentage, subcutaneous fat percentage, and skeletal muscle percentage...
October 19, 2016: Bioscience, Biotechnology, and Biochemistry
Xiran He, Bo Gao, Lei Zhou, Sidong Xiong
Viral myocarditis, which is mainly caused by coxsackievirus B3 (CVB3), affects about 5%-20% of the world population and still lacks efficient treatments. Green tea, a tonic and healthful beverage that was originated in ancient China, has been receiving considerable attention for its protective effect on cardiovascular diseases in recent years. In present investigation, we aimed to explore the effect of Green tea polyphenol epigallocatechin-3-gallate (EGCG) on CVB3-induced myocarditis and its underlying mechanism...
October 6, 2016: Journal of Cardiovascular Pharmacology
Amir Hadi, Makan Pourmasoumi, Marzieh Kafeshani, Jahangir Karimian, Mohammad Reza Maracy, Mohammad Hasan Entezari
OBJECTIVE: Additional oxygen consumption during intense exercises may lead to oxidative stress and contribute to muscular fatigue. Green tea and sour tea (Hibiscus sabdariffa L.), which contain various flavonoids and polyphenols, have many healthful properties such as anticarcinogenic, anti-inflammatory, and heart protecting effects. The aim of the present study was to assess the effects of green tea and sour tea supplementation on oxidative stress and muscle damage in soccer athletes...
October 13, 2016: Journal of Dietary Supplements
Lixia Chen, Huanbiao Mo, Ling Zhao, Weimin Gao, Shu Wang, Meghan M Cromie, Chuanwen Lu, Jia-Sheng Wang, Chwan-Li Shen
Pesticides, smoke, mycotoxins, polychlorinated biphenyls (PCBs), and arsenic are the most common environmental toxins and toxicants to humans. These toxins and toxicants may impact on human health at the molecular (DNA, RNA, or protein), organelle (mitochondria, lysosome, or membranes), cellular (growth inhibition or cell death), tissue, organ, and systemic levels. Formation of reactive radicals, lipid peroxidation, inflammation, genotoxicity, hepatotoxicity, embryotoxicity, neurological alterations, apoptosis, and carcinogenic events are some of the mechanisms mediating the toxic effects of the environmental toxins and toxicants...
May 27, 2016: Journal of Nutritional Biochemistry
Annewieke J W Verloop, Jean-Paul Vincken, Harry Gruppen
Formation of black tea thearubigins involves at least two of the following oxidation steps: (i) oligomerization, (ii) rearrangement, (iii) hydroxylation. The first two are mainly catalysed by polyphenol oxidase(PPO), whereas the enzyme responsible for hydroxylation has not yet been identified. Two main oxidative activities, peroxidase(POD) and PPO, occur in tea leaves. POD was hypothesized to be responsible for hydroxylation. Model systems with horseradish POD and mushroom tyrosinase were used investigating hydroxylation of theaflavins(TF)...
October 10, 2016: Journal of Agricultural and Food Chemistry
Chayanika Das, Kothandam Krishnamoorthy
Flexible micro-supercapacitors are needed to power ultra-small wearable electronic devices. Silk cocoons comprise microfibers of silk, which are an attractive natural resource to fabricate micro-supercapacitors (MSCs). These fibers are insulators, hence, they must be converted to conducting surfaces. Polyphenols from green tea have been used as a protective layer that also acted as a reducing agent to silver ion. The reduction of silver ion resulted in the formation of silver nanoparticles that subsequently reduced gold ions to gold...
October 7, 2016: ACS Applied Materials & Interfaces
Huaping Li, Na Jiang, Qing Liu, Aili Gao, Xin Zhou, Bihua Liang, Runxiang Li, Zhenjie Li, Huilan Zhu
Ultraviolet (UV) radiation causes skin injury and inflammation resulting in impaired immune response and increased risk of skin cancer. It has been shown that green tea polyphenols (GTPs) enhanced intracellular antioxidant defense and promoted the downregulation of proapoptotic genes, and they could be used to protect against the damage induced by UV irradiation. However, the high instability and poor bioavailability of GTPs impose restrictions on their potential pharmacological use. Here we show that carboxymethyl cellulose sodium (CMC-Na) had a stabilizing effect on GTPs under aqueous conditions and topical application of GTPs (emulsified in CMC-Na) had a strong photoprotective effect against acute UVB induced photodamage in uncovered (Uncv) hairless mice skin...
October 5, 2016: Photochemical & Photobiological Sciences
Patrizia Marinelli, Irantzu Pallares, Susanna Navarro, Salvador Ventura
The opportunistic pathogen Staphylococcus aureus is recognized as one of the most frequent causes of biofilm-associated infections. The recently discovered phenol soluble modulins (PSMs) are small α-helical amphipathic peptides that act as the main molecular effectors of staphylococcal biofilm maturation, promoting the formation of an extracellular fibril structure with amyloid-like properties. Here, we combine computational, biophysical and in cell analysis to address the specific contribution of individual PSMs to biofilm structure...
October 6, 2016: Scientific Reports
Tandeka Magcwebeba, Pieter Swart, Sonja Swanevelder, Elizabeth Joubert, Wentzel Gelderblom
Ultraviolet B (UVB) radiation is one of the major predisposing risk factors of skin cancer. The anticancer and photoprotective effects of unoxidized rooibos (Aspalathus linearis) and honeybush (Cyclopia) herbal teas, containing high levels of dihydrochalones and xanthones, respectively, have been demonstrated in skin cancer models in vivo. In the current study, the anti-inflammatory effects of methanol and aqueous extracts of these herbal teas were investigated in a UVB/HaCaT keratinocyte model with intracellular interleukin-1α (icIL-1α) accumulation as a biomarker...
October 2, 2016: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Terry E Lopez, Hoang M Pham, Benjamin V Nguyen, Yerazik Tahmasian, Shannon Ramsden, Volkan Coskun, Samuel E Schriner, Mahtab Jafari
Green tea has been found to increase the lifespan of various experimental animal models including the fruit fly, Drosophila melanogaster. High in polyphenolic content, green tea has been shown to reduce oxidative stress in part by its ability to bind free iron, a micronutrient that is both essential for and toxic to all living organisms. Due to green tea's iron-binding properties, we questioned whether green tea acts to increase the lifespan of the fruit fly by modulating iron regulators, specifically, mitoferrin, a mitochondrial iron transporter, and transferrin, found in the hemolymph of flies...
October 3, 2016: Archives of Insect Biochemistry and Physiology
Souradipta Ganguly, Taposh Kumar G, Sudarshan Mantha, Koustubh Panda
The bioavailability, tissue distribution and metabolic fate of the major tea polyphenols, catechins and theaflavins as well as their gallated derivatives are yet to be precisely elucidated on a single identification platform for assessment of their relative bioefficacy in vivo. This is primarily due to the lack of suitable analytical tools for their simultaneous determination especially in an in vivo setting, which continues to constrain the evaluation of their relative health beneficiary potential and therefore prospective therapeutic application...
2016: PloS One
Yi-Fang Li, Yi-Qun Chang, Jie Deng, Wei-Xi Li, Jie Jian, Jia-Suo Gao, Xin Wan, Hao Gao, Hiroshi Kurihara, Ping-Hua Sun, Rong-Rong He
The extraordinary hypolipidemic effects of polyphenolic compounds from tea have been confirmed in our previous study. To gain compounds with more potent activities, using the conformations of the most active compound revealed by molecular docking, a 3D-QSAR pancreatic lipase inhibitor model with good predictive ability was established and validated by CoMFA and CoMISA methods. With good statistical significance in CoMFA (r(2)cv = 0.622, r(2) = 0.956, F = 261.463, SEE = 0.096) and CoMISA (r(2)cv = 0...
October 3, 2016: Scientific Reports
Amel Ben Lagha, Daniel Grenier
Fusobacterium nucleatum has been associated with both periodontal disease and inflammatory bowel disease. This Gram-negative bacterium possesses a high inflammatory potential that may contribute to the disease process. We hypothesized that green and black tea polyphenols attenuate the inflammatory response of monocytes/macrophages mediated by F. nucleatum. We first showed that the tea extracts, EGCG and theaflavins reduce the NF-κB activation induced by F. nucleatum in monocytes. Since NF-κB is a key regulator of genes coding for inflammatory mediators, we tested the effects of tea polyphenols on secretion of IL-1β, IL-6, TNF-α, and CXCL8 by macrophages...
October 3, 2016: Scientific Reports
Youmei Wu, Jialu Wang, Wei Cai, Xiuhua Shen
Precocious puberty which impacts children physically and psychologically has become one of the health problem over the world. However, the mechanism and preventive measures of precocious puberty is still not clear. Recent studies suggested that leptin may act as the 'permissive factor' to initiate the puberty by regulating gonadotrophin-releasing hormone secretion. Previous evidence from animal and human studies found that tea polyphenols can reduce serum leptin levels in vivo and inhibit the expression of leptin in adipose tissue...
October 2016: Medical Hypotheses
Xiangyu Wang, Anqi Wang, Jun Ma, Minglai Fu
For the first time, an integrated green technology by coupling functional nanoscale zero-valent iron (NZVI) with ultrasound (US) was innovatively developed for the enhanced decolorization of malachite green (MG) and methylene blue (MB). The functional NZVI (TP-Fe) was successfully fabricated via a facile, one-step and environmentally-benign approach by directly introducing high pure tea polyphenol (TP), where TP contenting abundant epicatechin was employed as reductant, dispersant and capping agent. Note that neither additional extraction procedure nor protection gas was needed during the entire synthesis process...
January 2017: Chemosphere
Shuyuan Liu, Zhi Yu, Hongkai Zhu, Wei Zhang, Yuqiong Chen
BACKGROUND: Natural products have being used as potential inhibitors against carbohydrate-hydrolyzing enzymes to treat diabetes mellitus. Chinese dark tea has various interesting bioactivities. In this study, the active compounds from Qingzhuan dark tea were separated and their anti-diabetic activity was examined using an in vitro enzymatic model. METHODS: The chloroform, ethyl acetate, n-butanol, sediment and residual aqua fractions of a Chinese dark tea (Qingzhuan tea) were prepared by successively isolating the water extract with different solvents and their in vitro inhibitory activities against α-glucosidase were assessed...
September 29, 2016: BMC Complementary and Alternative Medicine
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