Inhibition property of green tea extract in relation to reserpine-induced ribosomal strips of rough endoplasmic reticulum (rER) of the rat kidney proximal tubule cells.

PubMed

Abdel-Majeed, Safer; Mohammad, Afzal; Shaima, Al-Bloushi; Mohammad, Rafique; Mousa, Shaker A

2009-12-01

The aim of this study was to evaluate the effect of green tea in inhibiting and reversing the nephrotoxicity of reserpine--a potent oxidative stress inducer--which induced cellular kidney damage. Serum biochemical parameters, antioxidant enzyme levels, thiobarbituric acid reactive substances (TBARS) and serum transaminases (glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT)) values and histopathology were systematically evaluated. Reserpine exposure led to increase the oxidative stress and organ injury was significantly observed through biochemical parameters and ultrastructural evaluation. Sprague-Dawely (S.D.) rats were intraperitonealy administered reserpine to induce oxidative kidney damage. Experimental rats were given green tea extract according to the protocol given below. Sixty rats were randomly divided into six groups, with 10 rats in each group. Reserpine was found to cause kidney proximal tubule damage, such as stripping and clustering of ribosomes from the rough endoplasmic reticulum (rER) and demolishing of mitochondrial christae with elevated level of oxidative stress markers, such as TBARS. While the ultrastructural study showed a revival of kidney proximal tubule cells as a result of the administration of green tea extract to rats. We suggest that green tea might elevate antioxidant defense system, clean up free radicals, lessen oxidative damages and protect kidney against reserpine-induced toxicity and thus had a potential protective effect.

Enzymatic treatment to improve the quality of black tea extracts.

PubMed

Chandini, S K; Rao, L Jaganmohan; Gowthaman, M K; Haware, D J; Subramanian, R

2011-08-01

Enzymatic extraction was investigated to improve the quality of black tea extracts with pretreatment of pectinase and tannase independently, successively and simultaneously. Pectinase improved the extractable-solids-yield (ESY) up to 11.5%, without much of an improvement in polyphenols recovery, while tannase pre-treatment showed a significant improvement in polyphenols recovery (14.3%) along with an 11.1% improvement in ESY. Among the four treatments, tannase-alone treatment showed the maximum improvement in tea quality, with higher polyphenols-in-extracted solids. Treatments involving tannase resulted in the significant release of gallic acid, due to its hydrolytic activity, leading to greater solubility besides favourably improving TF/TR ratio. The results suggested that employing a single enzyme, tannase, for the pre-treatment of black tea is desirable. Enzymatic extraction may be preferred over enzymatic clarification as it not only displayed reduction in tea cream and turbidity but also improved the recovery of polyphenols and ESY in the extract, as well as maintaining a good balance of tea quality. Copyright © 2011 Elsevier Ltd. All rights reserved.

Fermented green tea extract alleviates obesity and related complications and alters gut microbiota composition in diet-induced obese mice.

PubMed

Seo, Dae-Bang; Jeong, Hyun Woo; Cho, Donghyun; Lee, Bum Jin; Lee, Ji Hae; Choi, Jae Young; Bae, Il-Hong; Lee, Sung-Joon

2015-05-01

Obesity is caused by an imbalance between caloric intake and energy expenditure and accumulation of excess lipids in adipose tissues. Recent studies have demonstrated that green tea and its processed products (e.g., oolong and black tea) are introduced to exert beneficial effects on lipid metabolism. Here, we propose that fermented green tea (FGT) extract, as a novel processed green tea, exhibits antiobesity effects. FGT reduced body weight gain and fat mass without modifying food intake. mRNA expression levels of lipogenic and inflammatory genes were downregulated in white adipose tissue of FGT-administered mice. FGT treatment alleviated glucose intolerance and fatty liver symptoms, common complications of obesity. Notably, FGT restored the changes in gut microbiota composition (e.g., the Firmicutes/Bacteroidetes and Bacteroides/Prevotella ratios), which is reported to be closely related with the development of obesity and insulin resistance, induced by high-fat diets. Collectively, FGT improves obesity and its associated symptoms and modulates composition of gut microbiota; thus, it could be used as a novel dietary component to control obesity and related symptoms.

Rock Tea extract (Jasonia glutinosa) relaxes rat aortic smooth muscle by inhibition of L-type Ca(2+) channels.

PubMed

Valero, Marta Sofía; Oliván-Viguera, Aida; Garrido, Irene; Langa, Elisa; Berzosa, César; López, Víctor; Gómez-Rincón, Carlota; Murillo, María Divina; Köhler, Ralf

2015-12-01

In traditional herbal medicine, Rock Tea (Jasonia glutinosa) is known for its prophylactic and therapeutic value in various disorders including arterial hypertension. However, the mechanism by which Rock Tea exerts blood pressure-lowering actions has not been elucidated yet. Our aim was to demonstrate vasorelaxing effects of Rock Tea extract and to reveal its possible action mechanism. Isometric myography was conducted on high-K+-precontracted rings from rat thoracic aorta and tested extracts at concentrations of 0.5-5 mg/ml. Whole-cell patch-clamp experiments were performed in rat aortic vascular smooth muscle cells (line A7r5) to determine blocking effects on L-type Ca(2+) channels. Rock Tea extract relaxed the aorta contracted by high [K+] concentration dependently with an EC50 of ≈2.4 mg/ml and produced ≈75 % relaxation at the highest concentration tested. The L-type Ca(2+) channel blocker, verapamil (10(-6) M), had similar effects. Rock Tea extract had no effect in nominally Ca(2+)-free high-K(+) buffer but significantly inhibited contractions to re-addition of Ca(2+). Rock Tea extract inhibited the contractions induced by the L-type Ca(2+) channel activator Bay K 8644 (10(-5) M) and by phenylephrine (10(-6) M). Rock Tea extract and Y-27632 (10(-6) M), Rho-kinase inhibitor, had similar effects and the respective effects were not additive. Patch-clamp experiments demonstrated that Rock Tea extract (2.5 mg/ml) virtually abolished L-type Ca(2+) currents in A7r5. We conclude that Rock Tea extract produced vasorelaxation of rat aorta and that this relaxant effect is mediated by inhibition of L-type Ca(2+) channels. Rock Tea extracts may be of phytomedicinal value for prevention and adjuvant treatment of hypertension and other cardiovascular diseases.

Effective Subcritical Butane Extraction of Bifenthrin Residue in Black Tea.

PubMed

Zhang, Yating; Gu, Lingbiao; Wang, Fei; Kong, Lingjun; Qin, Guangyong

2017-03-30

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%. Further, the catechins, theanine, caffeine and aroma components, which determine the quality of the tea, fluctuated after SBE treatment. Compared with the uncrushed leaves, pesticide residues can more easily be removed from crushed leaves, and the practical extraction efficiency was 97%. These results indicate that SBE is a useful method to efficiently remove the bifenthrin, and as appearance is not relevant in the production process, tea leaves should first be crushed and then extracted in order that residual pesticides are thoroughly removed.

Recovery of catechin compounds from Korean tea by solvent extraction.

PubMed

Row, Kyung Ho; Jin, Yinzhe

2006-03-01

Catechin compounds from Korean green tea as potential sources of anticancer and antioxidant components were target materials in this work. The methodologies of solvent extraction and partition were utilized to recover catechin compounds from green tea. The optimum experimental condition was obtained by optimizing operating factors, such as, the extraction solvent, extraction time and operating temperature. After extracting the green tea with water at 80 degrees C for 40 min, the extract was partitioned with water/chloroform, which was best suited to remove caffeine impurity from the extract. Further, the resulting extract was partitioned water/ethyl acetate to deeply purify the catechin compounds of EGC, EC, EGCG and ECG. The experimental result in this work could be extended to preparative HPLC to obtain EGCG on commercial scale.

[Effect of tea extracts, catechin and caffeine against type-I allergic reaction].

PubMed

Shiozaki, T; Sugiyama, K; Nakazato, K; Takeo, T

1997-07-01

The antiallergic effects of green tea, oolong tea, and black tea extracts by hot water were examined. These extracts inhibited the passive cutaneous anaphylaxis (PCA) reaction of rat after oral administration. Three tea catechins, (--)-epigallocatechin (EGC), (--)-epicatechin gallate (ECg), and (--)-epigallocatechin gallate (EGCg) isolated from green tea showed stronger inhibitory effects than that of a green tea extract on the PCA reaction. The inhibitory effects of EGC and EGCg on the PCA reaction were greater than that of ECg. Caffeine also showed a inhibitory effect on the PCA reaction. These results indicate that tea could provide a significant protection against the type-I allergic reaction. These findings also suggest that tea catechins and caffeine play an important role in having an inhibitory effect on the type-I allergic reaction.

Determination of lutein from green tea and green tea by-products using accelerated solvent extraction and UPLC.

PubMed

Heo, Ji-Young; Kim, Suna; Kang, Jae-Hyun; Moon, Bokyung

2014-05-01

We aimed to identify the optimum conditions for the extraction of lutein from green tea using accelerated solvent extraction, and achieve improved analytical resolution and sensitivity between lutein and zeaxanthin using an ultra performance liquid chromatography (UPLC) system. The optimized method employed 80% ethanol as the extraction solvent, 160 °C as the temperature, 2 static cycles, and 5 min of static time. In the validation of the UPLC method, recovery was found to be in the range approximately 93.73 to 108.79%, with a correlation coefficient of 0.9974 and a relative standard deviation of <9.29% in inter- and intraday precision analyses. Finally, the lutein contents of green tea and green tea by-products were measured as 32.67 ± 0.70 and 18.18 ± 0.68 mg/100g dw, respectively. Furthermore, we verified that green tea by-products, which are discarded after producing green tea beverages, might be used as a great resource for massive lutein production. We have demonstrated that the common problem of inadequate resolution between lutein and zeaxanthin during carotenoid analyses can be overcome by optimizing the combined techniques of accelerated solvent extraction and ultra performance liquid chromatography (UPLC). UPLC was highly effective for saving time, solvent, and labor, as well as providing better resolution. The results in this study demonstrated that green tea by-products could be used as new sources for industrial lutein production owing to their massive production during the extraction of green tea beverages. © 2014 Institute of Food Technologists®

Effect of tea (Camellia sinensis) and olive (Olea europaea L.) leaves extracts on male mice exposed to diazinon.

PubMed

Al-Attar, Atef M; Abu Zeid, Isam M

2013-01-01

The present study was aimed to evaluate the effects of tea and olive leaves extracts and their combination in male mice intoxicated with a sublethal concentration of diazinon. Exposure of mice to 6.5 mg/kg body weight of diazinon for seven weeks resulted in statistical increases of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatine kinase, creatinine, glucose, triglycerides, and cholesterol, while the value of serum total protein was declined. Treating diazinon-intoxicated mice with tea and olive leaves extracts or their combination significantly attenuated the severe alterations in these hematobiochemical parameters. Moreover, the results indicated that the supplementation with combination of tea and olive leaves extracts led to more attenuation effect against diazinon toxicity. Additionally, these new findings suggest that the effect of tea and olive leaves extracts and their combination against toxicity of diazinon may be due to antioxidant properties of their chemical constituents. Finally, the present study indicated that the extracts of tea and olive leaves and their combination can be considered as promising therapeutic agents against hepatotoxicity, cardiotoxicity, nephrotoxicity, and metabolic disorders induced by diazinon and maybe by other toxicants and pathogenic factors.

Effect of Tea (Camellia sinensis) and Olive (Olea europaea L.) Leaves Extracts on Male Mice Exposed to Diazinon

PubMed Central

Al-Attar, Atef M.; Abu Zeid, Isam M.

2013-01-01

The present study was aimed to evaluate the effects of tea and olive leaves extracts and their combination in male mice intoxicated with a sublethal concentration of diazinon. Exposure of mice to 6.5 mg/kg body weight of diazinon for seven weeks resulted in statistical increases of serum alanine aminotransferase, aspartate aminotransferase, gamma glutamyl transferase, alkaline phosphatase, creatine kinase, creatinine, glucose, triglycerides, and cholesterol, while the value of serum total protein was declined. Treating diazinon-intoxicated mice with tea and olive leaves extracts or their combination significantly attenuated the severe alterations in these hematobiochemical parameters. Moreover, the results indicated that the supplementation with combination of tea and olive leaves extracts led to more attenuation effect against diazinon toxicity. Additionally, these new findings suggest that the effect of tea and olive leaves extracts and their combination against toxicity of diazinon may be due to antioxidant properties of their chemical constituents. Finally, the present study indicated that the extracts of tea and olive leaves and their combination can be considered as promising therapeutic agents against hepatotoxicity, cardiotoxicity, nephrotoxicity, and metabolic disorders induced by diazinon and maybe by other toxicants and pathogenic factors. PMID:23691503

Comparative healing property of kombucha tea and black tea against indomethacin-induced gastric ulceration in mice: possible mechanism of action.

PubMed

Banerjee, Debashish; Hassarajani, Sham A; Maity, Biswanath; Narayan, Geetha; Bandyopadhyay, Sandip K; Chattopadhyay, Subrata

2010-12-01

The healing activity of black tea (BT) and BT fermented with Candida parapsilosis and kombucha culture, designated as CT and KT respectively against the indomethacin-induced stomach ulceration has been studied in a mouse model. The KT sample (KT4) produced by fermenting BT for four days, showed the best DPPH radical scavenging capacity and phenolics contents. Hence the ulcer-healing activity of KT4 was compared with those of CT4 and BT. All the tea extracts (15 mg kg(-1)) could effectively heal the gastric ulceration as revealed from the histopathological and biochemical studies, with relative efficacy as KT4 > CT4 ∼ BT. The healing capacities of the tea extracts could be attributed to their antioxidant activity as well as the ability to protect the mucin content of the gastric tissues. In addition, the ability of KT4 to reduce gastric acid secretion might also contribute to its ulcer-healing activity. The tea preparation KT4 (15 mg kg(-1)) was as effective as the positive control, omeprazole (3 mg kg(-1)) in ulcer healing.

Green tea extract impairs meat emulsion properties by disturbing protein disulfide cross-linking.

PubMed

Jongberg, Sisse; Terkelsen, Linda de S; Miklos, Rikke; Lund, Marianne N

2015-02-01

The dose-dependent effects of green tea extract (100, 500, or 1500ppm) on the textural and oxidative stability of meat emulsions were investigated, and compared to a control meat emulsion without extract. All levels of green tea extract inhibited formation of TBARS as a measure for lipid oxidation. Overall protein thiol oxidation and myosin heavy chain (MHC) cross-linking were inhibited by 100ppm green tea extract without jeopardizing the textural stability, while increasing concentrations of extract resulted in reduced thiol concentration and elevated levels of non-reducible protein modifications. Addition of 1500ppm green tea extract was found to modify MHC as evaluated by SDS-PAGE combining both protein staining and specific thiol staining, indicating that protein modifications generated through reactions of green tea phenolic compounds with protein thiols, disrupted the meat emulsion properties leading to reduced water holding capacity and textural stability. Hence, a low dose of green tea extract preserves both the textural and the oxidative stability of the meat proteins. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interaction mechanism between green tea extract and human α-amylase for reducing starch digestion.

PubMed

Miao, Ming; Jiang, Bo; Jiang, Huan; Zhang, Tao; Li, Xingfeng

2015-11-01

This study evaluated the inhibitory effects of the green tea extract on human pancreatic α-amylase activity and its molecular mechanism. The green tea extract was composed of epicatechin (59.2%), epigallocatechin gallate (14.6%) and epicatechin gallate (26.2%) as determined by HPLC analysis. Enzyme activity measurement showed that % inhibition and IC50 of the green tea extract (10%, based on starch) were 63.5% and 2.07 mg/ml, respectively. The Michaelis-Menten constant remained unchanged but the maximal velocity decreased from 0.43 (control) to 0.07 mg/(ml × min) (4 mg/ml of the green tea extract), indicating that the green tea extract was an effective inhibitor against α-amylase with a non-competitive mode. The fluorescence data revealed that the green tea extract bound with α-amylase to form a new complex with static quenching mechanism. Docking study showed the epicatechin gallate in the green tea extract presented stronger affinity than epigallocatechin gallate, with more number of amino acid residues involved in amylase binding with hydrogen bonds and Van der Waals forces. Thus, the green tea extract could be used to manipulate starch digestion for potential health benefits. Copyright © 2015 Elsevier Ltd. All rights reserved.

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

PubMed

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.

The Effects of Green Tea Extract on Working Memory in Healthy Women.

PubMed

Liu, Y; Fly, A D; Wang, Z; Klaunig, J E

2018-01-01

This study aimed to examine the effects of green tea extract on working memory in healthy younger (21 - 29 y) and older (50 - 63 y) women. A single-blind, placebo-controlled, crossover design was used. A university laboratory. Twenty non-smoking Caucasian women were recruited in the younger (10) and older (10) age group. Subjects received 5.4 g green tea extract (at least 45% epigallocatechin-3-gallate) or placebo (cornstarch) within a 24-hour period. Working memory was measured by reading span and N-back task paradigm. Blood sample (20 mL) was collected and measured for plasma malondialdehyde (MDA) and total antioxidant capacity (TEAC) concentration. A 24-hour recall was conducted for each treatment period to ensure similar dietary patterns. Green tea extract significantly improved reading span performance in older women, indicated by higher absolute and partial scores of reading span. No significant changes were observed in the younger group. N-back latencies and accuracies were not significantly different after green tea treatment in either age group. Plasma concentration of MDA and TEAC were not different after green tea extract in either group. Acute supplementation of decaffeinated green tea extract may enhance working memory capacity of women between 50 to 63 years of age. This study provides preliminary evidence that consumption of green tea extract may enhance the cognitive performance in older adults and thus provide potential chemopreventive benefits in this group. The mechanism should be explored in future research.

Green and black tea inhibit cytokine-induced IL-8 production and secretion in AGS gastric cancer cells via inhibition of NF-κB activity.

PubMed

Gutierrez-Orozco, Fabiola; Stephens, Brian R; Neilson, Andrew P; Green, Rodney; Ferruzzi, Mario G; Bomser, Joshua A

2010-10-01

Consumption of tea is associated with a reduced risk for several gastrointestinal cancers. Inflammatory processes, such as secretion of IL-8 from the gastric epithelium in response to chronic chemokine or antigen exposure, serve both as a chemoattractant for white blood cells and a prerequisite for gastric carcinogenesis. In this study, the gastric adenocarcinoma cell line AGS was used to investigate the effect of green tea extract, black tea extract, and epigallocatechin gallate (EGCG), the most abundant catechin in tea, on cytokine-induced inflammation. AGS cells were stimulated with interleukin-1β (IL-1β) to initiate inflammation, followed by exposure to either tea extracts or EGCG. We found that both green and black tea extracts at concentrations of 20 and 2 µM total catechins, respectively, significantly (p < 0.05) inhibited IL-1β-induced IL-8 production and secretion to a similar extent. Treatment of AGS cells with EGCG (8 µM) produced similar reductions in IL-1β-induced IL-8 production and secretion. Inhibition of NF-κB activity was found to be responsible, in part, for these observed effects. Our findings demonstrate that both green and black tea extracts with distinctly different catechin profiles, are capable of disrupting the molecular link between inflammation and carcinogenesis via inhibition of NF-κB activity in AGS cells. © Georg Thieme Verlag KG Stuttgart · New York.

Removal of caffeine from green tea by microwave-enhanced vacuum ice water extraction.

PubMed

Lou, Zaixiang; Er, Chaojuan; Li, Jing; Wang, Hongxin; Zhu, Song; Sun, Juntao

2012-02-24

In order to selectively remove caffeine from green tea, a microwave-enhanced vacuum ice water extraction (MVIE) method was proposed. The effects of MVIE variables including extraction time, microwave power, and solvent to solid radio on the removal yield of caffeine and the loss of total phenolics (TP) from green tea were investigated. The optimized conditions were as follows: solvent (mL) to solid (g) ratio was 10:1, microwave extraction time was 6 min, microwave power was 350 W and 2.5 h of vacuum ice water extraction. The removal yield of caffeine by MVIE was 87.6%, which was significantly higher than that by hot water extraction, indicating a significant improvement of removal efficiency. Moreover, the loss of TP of green tea in the proposed method was much lower than that in the hot water extraction. After decaffeination by MVIE, the removal yield of TP tea was 36.2%, and the content of TP in green tea was still higher than 170 mg g(-1). Therefore, the proposed microwave-enhanced vacuum ice water extraction was selective, more efficient for the removal of caffeine. The main phenolic compounds of green tea were also determined, and the results indicated that the contents of several catechins were almost not changed in MVIE. This study suggests that MVIE is a new and good alternative for the removal of caffeine from green tea, with a great potential for industrial application. Copyright © 2011 Elsevier B.V. All rights reserved.

Black tea increases hypertonic stress resistance in C. elegans.

PubMed

Yuan, Pei; Pan, Lian-Yun; Xiong, Li-Gui; Tong, Jie-Wen; Li, Juan; Huang, Jian-An; Gong, Yu-Shun; Liu, Zhong-Hua

2018-06-22

Here we identified that BTE (black tea extract), within the studied concentration range, is more effective than GTE (green tea extract) in protecting C. elegans against hypertonic stress, by enhancing survival after exposure to various salts, and alleviating suffered motility loss and body shrinkage. The mechanism of such protection may be due to the ability of black tea to induce the conserved WNK/GCK signaling pathway and down-regulation of the expression levels of nlp-29. Intriguingly, black tea does not relieve hypertonicity-induced protein damage. The findings implicate the potential health benefits of black tea consumed worldwide.

Enhancement of fermentation process in Pu-erh tea by tea-leaf extract.

PubMed

Hou, C W; Jeng, K C; Chen, Y S

2010-01-01

Pu-erh tea is known as a fermented tea and longer storage enhances its flavor and taste. Recently, Aspergillus, Blastobotrys, and Streptomyces are found to play important roles in nutritional enhancement of Pu-erh tea by fermentation. Since water and temperature affect the microbial growth, we therefore explored the factors that might enhance the Pu-erh tea fermentation. The results showed that the addition of fresh tea-leaf extract (TLE) enhanced the withered tea fermentation (at 37 degrees C, 80 to 85% RH) as compared with the water only. Contents of statin, GABA, gallic acid, DPPH scavenging and polyphenol oxidase (PPO) activities were increased, whereas polyphenols and caffeine were decreased over 6 mo. TLE dose-dependently enhanced some of the qualities (that is, statin, PPO) of Pu-erh tea significantly as compared with the water only. The effect was related to the increase population of A. niger and A. carbonarius at 6 mo (from 7.6 +/- 1.2 x 10(1) and 3.2 +/- 1.3 x 10(1) to 3.1 +/- 1.2 x 10(6) and 2.4 +/- 1.1 x 10(5) colony forming units [CFU]/g, respectively). After drying process (90 degrees C, 30 min), the total microbial count from these samples returned to background level (3 +/- 0.5 x 10(2) CFU/g). None of ochratoxin and fumonisin, toxins from Aspergillus, was detected in the final products. The flavor and taste were also enhanced by treatment with TLE. The inoculation with S. cinereus Y11 with 2% TLE further enhanced these functional contents (about 2-fold increase of statin level) in the experimental Pu-erh tea. Therefore, this result may add a new process for Pu-erh tea manufacture.

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

PubMed

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

1991-02-01

Extracts of black tea exhibited bactericidal activity against Vibrio cholerae O1. The tea extract inhibited the haemolysin activity of V. cholerae O1, El Tor and the morphological changes of Chinese hamster ovary cells induced by cholera toxin. Tea extract also reduced fluid accumulation induced by cholera toxin in sealed adult mice and by V. cholerae O1 in ligated intestinal loops of rabbits. These findings suggest that tea has protective activity against V. cholerae O1.

Inhibition of attachment of oral bacteria to immortalized human gingival fibroblasts (HGF-1) by tea extracts and tea components

PubMed Central

2013-01-01

Background Tea has been suggested to promote oral health by inhibiting bacterial attachment to the oral cavity. Most studies have focused on prevention of bacterial attachment to hard surfaces such as enamel. Findings This study investigated the effect of five commercial tea (green, oolong, black, pu-erh and chrysanthemum) extracts and tea components (epigallocatechin gallate and gallic acid) on the attachment of five oral pathogens (Streptococcus mutans ATCC 25175, Streptococcus mutans ATCC 35668, Streptococcus mitis ATCC 49456, Streptococcus salivarius ATCC 13419 and Actinomyces naeslundii ATCC 51655) to the HGF-1 gingival cell line. Extracts of two of the teas (pu-erh and chrysanthemum) significantly (p < 0.05) reduced attachment of all the Streptococcus strains by up to 4 log CFU/well but effects of other teas and components were small. Conclusions Pu-erh and chrysanthemum tea may have the potential to reduce attachment of oral pathogens to gingival tissue and improve the health of oral soft tissues. PMID:23578062

Inhibition of attachment of oral bacteria to immortalized human gingival fibroblasts (HGF-1) by tea extracts and tea components.

PubMed

Wang, Yi; Chung, Felicia F L; Lee, Sui M; Dykes, Gary A

2013-04-11

Tea has been suggested to promote oral health by inhibiting bacterial attachment to the oral cavity. Most studies have focused on prevention of bacterial attachment to hard surfaces such as enamel. This study investigated the effect of five commercial tea (green, oolong, black, pu-erh and chrysanthemum) extracts and tea components (epigallocatechin gallate and gallic acid) on the attachment of five oral pathogens (Streptococcus mutans ATCC 25175, Streptococcus mutans ATCC 35668, Streptococcus mitis ATCC 49456, Streptococcus salivarius ATCC 13419 and Actinomyces naeslundii ATCC 51655) to the HGF-1 gingival cell line. Extracts of two of the teas (pu-erh and chrysanthemum) significantly (p < 0.05) reduced attachment of all the Streptococcus strains by up to 4 log CFU/well but effects of other teas and components were small. Pu-erh and chrysanthemum tea may have the potential to reduce attachment of oral pathogens to gingival tissue and improve the health of oral soft tissues.

Inhibition of urinary bladder tumors induced by N-butyl-N-(4-hydroxybutyl)-nitrosamine in rats by green tea.

PubMed

Sato, D

1999-02-01

Recently, the anticarcinogenic effects of green tea have been studied in sites other than the urinary tract. The present study examined the inhibition by green tea of vesical tumors induced in rats by N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN). In the first series of experiments, 0.05% BBN was added to the drinking water of rats and remained present for 5 weeks. In one experiment, six groups of animals received either tap water, green tea, matcha, hojicha, oolong tea or black tea from week 6. In a second experiment, three groups of rats received either tap water, green tea extract or powdered green tea mixed into a pellet diet from week 6. In a third experiment, five groups of rats were fed a pellet diet with addition of either 0, 0.15, 1.5 or 3.0% powdered green tea from week 6. All rats were killed and examined at 40 weeks. Green tea, particularly green tea leaves, dose-dependently inhibited the growth of BBN-induced urinary bladder tumors when given after the carcinogen. Green tea may inhibit bladder tumor growth.

Recent advances in tea polysaccharides: Extraction, purification, physicochemical characterization and bioactivities.

PubMed

Chen, Guijie; Yuan, Qingxia; Saeeduddin, Muhammad; Ou, Shiyi; Zeng, Xiaoxiong; Ye, Hong

2016-11-20

Tea has a long history of medicinal and dietary use. Tea polysaccharide (TPS) is regarded as one of the main bioactive constituents of tea and is beneficial for health. Over the last decades, considerable efforts have been devoted to the studies on TPS: extraction, structural feature and bioactivity of TPS. However, it has been received much less attention compared with tea polyphenols. In order to provide new insight for further development of TPS in functional foods, in present review we summarize the recent literature, update the information and put forward future perspectives on TPS covering its extraction, purification, quantitative determination techniques as well as physicochemical characterization and bioactivities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synergistic Effect of Green Tea Polyphenols and Vitamin D on Chronic Inflammation-Induced Bone Loss in Female Rats

USDA-ARS?s Scientific Manuscript database

Our recent study demonstrated a bone-protective role of green tea polyphenols (GTPs), extracted from green tea, in chronic inflammation-induced bone loss of female rats through reduction of inflammation and oxidative stress. This study further examines effects of GTPs in conjunction with vitamin D (...

Development of tea extracts and chitosan composite films for active packaging materials.

PubMed

Peng, Yong; Wu, Yan; Li, Yunfei

2013-08-01

The effects of 0.5%, 1% and 2% green tea extracts (GTE) and black tea extracts (BTE) on the physical, structural and antioxidant properties of chitosan films were investigated. Results showed that the addition of tea extracts significantly decreased water vapour permeability and increased the antioxidant ability of films. The DPPH radical scavenging ability of GTE films was stronger than that of BTE films in all food simulants (0%, 20%, 75% and 95% ethanol). The equilibration time in different food simulants decreased with the increased ethanol concentration. DSC and FTIR spectra analysis indicated that there was strong interaction in film matrix, which could be reflected by the physical and mechanical properties of composite films. This study revealed that an active chitosan film could be obtained by incorporation of tea extracts, which may provide new formulation options for developing an antioxidant active packaging. Copyright © 2013 Elsevier B.V. All rights reserved.

Potential use of tea extract as a complementary mouthwash: comparative evaluation of two commercial samples.

PubMed

Esimone, C O; Adikwu, M U; Nwafor, S V; Okolo, C O

2001-10-01

To evaluate the potential of using tea extracts as complementary mouthwash and to test the comparative efficacy of two commercial samples. A randomized controlled trial with 30 healthy human volunteers was carried out. The subjects were randomly assigned to 5 groups of 6 subjects per group. The ability of Ndu tea (from Cameroon) and Lipton tea (from Nigeria) to reduce colony forming units (CFU) in the liquid expectorated after 60 seconds of gargling from the mouth of the volunteers at 5 and 60 minutes were evaluated. These were compared to the values obtained from bank water and Minty Brett (thymol 0.047%), a standard antiseptic. University of Nigeria, Nsukka, Enugu State, Nigeria. Thirty healthy human volunteers (18 males and 12 females, between 22-30 years of age) who met the eligibility requirement of being nonsmokers and not taking any other antimicrobial agent were selected for the study. Relative to the bank water, the results indicated that the hot water extract of both teas significantly (p < 0.05) reduced CFU per milliliter in the liquid expectorated after gargling at both 5 and 60 minutes. Minty Brett showed higher activity than both tea extracts; however, unlike Minty Brett both extracts still reduced the CFU per milliliter at time 60 minutes (an indication of longer duration of activity). The combination of the tea extracts with sodium lauryl sulfate (1.2% w/v), a surfactant and emulsifier, significantly increased the antimicrobial activity relative to each tea alone. Comparatively, the activity of Ndu tea was found to be slightly higher than that of Lipton tea but this was not significant (p < 0.05). Lipton and Ndu tea extracts potently reduced the CFU per milliliter. This activity was potentiated by sodium lauryl sulfate. Although Minty Brett had more potent antimicrobial activity, both tea extracts have longer duration of activity. The results indicate the potential usefulness of tea extracts as a complementary mouthwash.

Extraction and removal of caffeine from green tea by ultrasonic-enhanced supercritical fluid.

PubMed

Tang, Wei-Qiang; Li, Di-Cai; Lv, Yang-Xiao; Jiang, Jian-Guo

2010-05-01

Low-caffeine or caffeine-removed tea and its products are widely welcomed on market in recent years. In the present study, we adopt ultrasonic-enhanced supercritical fluid extraction process to remove caffeine from green tea. An orthogonal experiment (L16 (4(5))) was applied to optimize the best removal conditions. Extraction pressure, extraction time, power of ultrasound, moisture content, and temperature were the main factors to influence the removal rate of caffeine from green tea. The 5 factors chosen for the present investigation were based on the results of a single-factor test. The optimum removal conditions were determined as follows: extraction pressure of 30 MPa, temperature at 55 degrees C, time of 4 h, 30% moisture content, and ultrasound power of 100 W. Chromatogram and ultraviolet analysis of raw material and decaffeinates suggests that under optimized conditions, the caffeine of green tea was effectively removed and minished without damaging the structure of active ingredients in green tea.

Green tea extract as an anti-browning agent for cloudy apple juice.

PubMed

Klimczak, Inga; Gliszczyńska-Świgło, Anna

2017-03-01

Enzymatic browning of fruits and vegetables and their products is an important factor worsening their quality. The influence of five green tea extracts at the concentrations of 1 g L -1 , 2 g L -1 and 3 g L -1 on polyphenol oxidase (PPO) activity in fresh cloudy apple juice was investigated. Moreover, PPO inhibition by tea extract and colour stability of juice during short-time refrigerated storage was studied. The changes of juice colour during storage was expressed as the total colour differences (ΔE*), browning index (BI), yellowness index (YI), and the absorbance at 420 nm (A 420 ). All extracts inhibited PPO activity in fresh apple juice in concentration-dependent manner. PPO activity in pure apple juice decreased by 7% after 48 h, whereas PPO activity in samples with 1 g L -1 , 2 g L -1 and 3 g L -1 tea extract decreased by 53%, 74%, and 96%, respectively. Browning of apple juice during storage decreased with increased concentration of green tea extract. After 48 h, extract at 1 g L -1 , 2 g L -1 and 3 g L -1 inhibited browning of juice expressed as BI by 48%, 60%, and 86%, respectively, comparing to pure apple juice. Green tea extract may be an effective anti-browning agent for short-time stored cloudy apple juices. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Spectral features based tea garden extraction from digital orthophoto maps

NASA Astrophysics Data System (ADS)

Jamil, Akhtar; Bayram, Bulent; Kucuk, Turgay; Zafer Seker, Dursun

2018-05-01

The advancements in the photogrammetry and remote sensing technologies has made it possible to extract useful tangible information from data which plays a pivotal role in various application such as management and monitoring of forests and agricultural lands etc. This study aimed to evaluate the effectiveness of spectral signatures for extraction of tea gardens from 1 : 5000 scaled digital orthophoto maps obtained from Rize city in Turkey. First, the normalized difference vegetation index (NDVI) was derived from the input images to suppress the non-vegetation areas. NDVI values less than zero were discarded and the output images was normalized in the range 0-255. Individual pixels were then mapped into meaningful objects using global region growing technique. The resulting image was filtered and smoothed to reduce the impact of noise. Furthermore, geometrical constraints were applied to remove small objects (less than 500 pixels) followed by morphological opening operator to enhance the results. These objects served as building blocks for further image analysis. Finally, for the classification stage, a range of spectral values were empirically calculated for each band and applied on candidate objects to extract tea gardens. For accuracy assessment, we employed an area based similarity metric by overlapping obtained tea garden boundaries with the manually digitized tea garden boundaries created by experts of photogrammetry. The overall accuracy of the proposed method scored 89 % for tea gardens from 10 sample orthophoto maps. We concluded that exploiting the spectral signatures using object based analysis is an effective technique for extraction of dominant tree species from digital orthophoto maps.

A study on toxicity of gasoline and GM-10 on liver of mice and it's amelioration by black tea extract.

PubMed

Verma, Ramtej Jayram; Dave, Manjeet; Mathuria, Neeta

2008-01-01

The aim of present study is to investigate the ameliorative effect of black tea extract on gasoline and GM-10 induced toxicity in liver of mice. Eighty healthy male mice weighing 38-40 g approximately were divided into eight groups which included untreated control and various treated groups. Mice were treated with Gasoline 462 mg/kg/day and GM-10 low dose (206 mg/kg/day) and high dose (412 mg/kg/day) subcutaneously for 30 days. Black tea extract was given as 2 g/100 mL drinking water (2% w/v) instead of pure drinking water. All the animals were sacrificed on 31st day by cervical dislocation and livers were isolated and weighed. Parameters such as lipid peroxidation, catalase, superoxide dismutase, glutathione peroxidase, glutathione and total ascorbic acid were studied. The results revealed dose-dependent toxicity of gasoline and GM-10 on liver. Administration of black tea extract ameliorates this toxicity of gasoline and GM-10 in liver of mice. This proves the effective ameliorative effect of black tea extract.

Anti-inflammatory activity of green versus black tea aqueous extract in a rat model of human rheumatoid arthritis.

PubMed

Ramadan, Gamal; El-Beih, Nadia M; Talaat, Roba M; Abd El-Ghffar, Eman A

2017-02-01

Recently, there has been an increasing interest in tea (Camellia sinensis) as a protective agent against inflammatory diseases. Here, we evaluated/compared the anti-inflammatory activity of two different doses (0.5 and 1.0 g/kg body weight) of green tea aqueous extract (GTE, rich in catechins) and black tea aqueous extract (BTE, rich in theaflavins and thearubigins) in rat adjuvant-induced arthritis (AIA). Adjuvant-induced arthritis rat model received orally/daily distilled water as vehicle, indomethacin (1.0 mg/kg body weight; a non-steroidal/anti-inflammatory drug), or tea aqueous extracts (for 28 or 14 consecutive days starting from day 0 or 14 of arthritis induction, respectively). The present study showed that only the high dose of GTE (from day 0) significantly alleviated (P < 0.05-0.001) all complications shown in arthritic rats, including synovial joint inflammation, elevation in erythrocyte sedimentation rate, blood leukocytosis (due to lymphocytosis and neutrocytosis), and changes in weight/cellularity of lymphoid organs. The anti-arthritic activity of the high dose of GTE (from day 0) was comparable (P > 0.05) with that of indomethacin (12.9-53.8 vs. 9.5-48.4%, respectively) and mediated by significantly decreasing and down-regulating (P < 0.001) the systemic production of pro-inflammatory cytokines and the expression of chemokine receptor-5 in synovial tissues, respectively. Moreover, the anti-arthritic activity of tea aqueous extracts was in the following order: high dose of GTE > low dose of GTE ≥ high dose of BTE > low dose of BTE. The present study proved the anti-inflammatory activity of GTE over BTE and equal to that of indomethacin in AIA rat model. © 2015 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.

Extraction of caustic potash from spent tea for biodiesel Production

NASA Astrophysics Data System (ADS)

Sulaiman, Sarina; Faiz Che Fisol, Ahmad; Sharikh, Atikah Mohamed; Noraini Jimat, Dzun; Jamal, Parveen

2018-01-01

Biodiesel is an alternative to non-renewable fossil fuels due to its low gas emission and economical value. This study aims to extract caustic potash (KOH) from spent tea and to optimize the transesterfication process based on parameters such as amount of catalyst, reaction temperature and methanol to oil ratio. The spent tea was first dried at 60°C prior to calcination at 600°C for two hours. Caustic Potash were extracted from the calcined spent tea. The transesterification process was done based on Design of Experiments (DOE) to study the effects of amount of catalyst ranging from 0.5 wt % to 2.5 wt %, reaction temperature from 55°C to 65°C and methanol to oil ratio from 6:1 to 12:1 at a constant agitation rate of 300 rpm for three hours. The calcined spent tea produced was recorded the highest at 54.3 wt % and the extracted catalyst was 2.4 wt %. The optimized biodiesel yield recorded was 56.95% at the optimal conditions of 2.5 wt % amount of catalyst, 65°C reaction temperature and 9:1 methanol to oil ratio.

Total phenolics and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts, vitamin E, and tert-butylhydroquinone.

PubMed

Rababah, Taha M; Hettiarachchy, Navam S; Horax, Ronny

2004-08-11

The total phenolics and antioxidant activities of fenugreek, green tea, black tea, grape seed, ginger, rosemary, gotu kola, and ginkgo extracts, vitamin E, and tert-butylhydroquinone, were determined. Grape seed and green tea were analyzed for their phenolic constituents using high-performance liquid chromatography. The total phenolics of the plant extracts, determined by the Folin-Ciocalteu method, ranged from 24.8 to 92.5 mg of chlorogenic acid equivalent/g dry material. The antioxidant activities of methanolic extracts determined by conjugated diene measurement of methyl linoleate were 3.4-86.3%. The antioxidant activity of the extracts using chicken fat by an oxidative stability instrument (4.6-10.2 h of induction time) followed a similar trend in antioxidant activity as determined by the Folin-Ciocalteu method. Seven phenolics in grape seed and green tea extracts were identified that ranged from 15.38 to 1158.49 and 18.3 to 1087.02 mg/100 g of extract, respectively. Plant extracts such as green tea and grape seed extracts can be used to retard lipid oxidation in a variety of food products.

Use of plant extracts for tea pest management in India.

PubMed

Roy, Somnath; Handique, Gautam; Muraleedharan, Narayanannair; Dashora, Kavya; Roy, Sudipta Mukhopadhyay; Mukhopadhyay, Ananda; Babu, Azariah

2016-06-01

India is the second largest producer of black tea in the world. The biggest challenge for tea growers of India nowadays is to combat pests and diseases. Tea crop in India is infested by not less than 720 insect and mite species. At least four sucking pests and six chewing pests have well established themselves as regular pests causing substantial damage to this foliage crop. Various synthetic pesticides are widely used for the management of tea pests in India. Applications of such large quantity of pesticides could cause various problems such as development of resistance, deleterious effects on non-target organisms such as insect predators and parasitoids, upsetting the ecological balance, and accumulation of pesticide residues on tea leaves. There is a growing demand for organic tea or at least pesticide residue free tea in the international market which affects the export price. There is also a higher emphasis of implementation of new regulations on internationally traded foods and implementation of Plant Protection Code (PPC) for tea by the Government of India. This necessitates a relook into the usage pattern of synthetic pesticides on this crop. There are various non-chemical interventions which are being worked out for their sustainability, compatibility, and eco-friendly properties which can gradually replace the use of toxic chemicals. The application of plant extracts with insecticidal properties provides an alternative to the synthetic pesticides. Botanical products, especially neem-based products, have made a relatively moderate impact in tea pest control. Research has also demonstrated the potential of 67 plant species as botanical insecticides against tea pests. The majority of plant products used in pest management of tea in India are in the form of crude extracts prepared locally in tea garden itself, and commercial standardized formulations are not available for most of the plants due to lack of scientific research in the area. Apart from systematic

Ameliorative Influence of Green Tea Extract on Copper Nanoparticle-Induced Hepatotoxicity in Rats

NASA Astrophysics Data System (ADS)

Ibrahim, Marwa A.; Khalaf, A. A.; Galal, Mona K.; Ogaly, Hanan A.; H. M. Hassan, Azza

2015-09-01

The potential toxicity of copper nanoparticles (CNPs) to the human health and environment remains a critical issue. In the present study, we investigated the protective influence of an aqueous extract of green tea leaves (GTE) against CNPs-induced (20-30 nm) hepatotoxicity. Four different groups of rats were used: group I was the control, group II received CNPs (40 mg/kg BW), group III received CNPs plus GTE, and group IV received GTE alone. We highlighted the hepatoprotective effect of GTE against CNPs toxicity through monitoring the alteration of liver enzyme activity, antioxidant defense mechanism, histopathological alterations, and DNA damage evaluation. The rats that were given CNPs only had a highly significant elevation in liver enzymes, alteration in oxidant-antioxidant balance, and severe pathological changes. In addition, we detected a significant elevation of DNA fragmentation percentage, marked DNA laddering, and significance over expression of both caspase-3 and Bax proteins. The findings for group III clarify the efficacy of GTE as a hepatoprotectant on CNPs through improving the liver enzyme activity, antioxidant status, as well as suppressing DNA fragmentation and the expression of the caspase-3 and Bax proteins. In conclusion, GTE was proved to be a potential hepatoprotective additive as it significantly ameliorates the hepatotoxicity and apoptosis induced by CNPs.

Topical application of green and white tea extracts provides protection from solar-simulated ultraviolet light in human skin.

PubMed

Camouse, Melissa M; Domingo, Diana Santo; Swain, Freddie R; Conrad, Edward P; Matsui, Mary S; Maes, Daniel; Declercq, Lieve; Cooper, Kevin D; Stevens, Seth R; Baron, Elma D

2009-06-01

Tea polyphenols have been found to exert beneficial effects on the skin via their antioxidant properties. We sought to determine whether topical application of green tea or white tea extracts would prevent simulated solar radiation-induced oxidative damages to DNA and Langerhans cells that may lead to immune suppression and carcinogenesis. Skin samples were analysed from volunteers or skin explants treated with white tea or green tea after UV irradiation. In another group of patients, the in vivo immune protective effects of green and white tea were evaluated using contact hypersensitivity to dinitrochlorobenzene. Topical application of green and white tea offered protection against detrimental effects of UV on cutaneous immunity. Such protection is not because of direct UV absorption or sunscreen effects as both products showed a sun protection factor of 1. There was no significant difference in the levels of protection afforded by the two agents. Hence, both green tea and white tea are potential photoprotective agents that may be used in conjunction with established methods of sun protection.

Review and perspective on the composition and safety of green tea extracts

USDA-ARS?s Scientific Manuscript database

The growing body of evidence regarding the putative health benefits of green tea (Camellia sinensis), including reduced risk of cancer and cardiovascular disease, has led to an increase in the consumption of brewed green tea and the formulation of green tea extracts (GTE) into a variety of food and ...

Liver-related safety assessment of green tea extracts in humans: a systematic review of randomized controlled trials

PubMed Central

Isomura, T; Suzuki, S; Origasa, H; Hosono, A; Suzuki, M; Sawada, T; Terao, S; Muto, Y; Koga, T

2016-01-01

There remain liver-related safety concerns, regarding potential hepatotoxicity in humans, induced by green tea intake, despite being supposedly beneficial. Although many randomized controlled trials (RCTs) of green tea extracts have been reported in the literature, the systematic reviews published to date were only based on subjective assessment of case reports. To more objectively examine the liver-related safety of green tea intake, we conducted a systematic review of published RCTs. A systematic literature search was conducted using three databases (PubMed, EMBASE and Cochrane Central Register of Controlled Trials) in December 2013 to identify RCTs of green tea extracts. Data on liver-related adverse events, including laboratory test abnormalities, were abstracted from the identified articles. Methodological quality of RCTs was assessed. After excluding duplicates, 561 titles and abstracts and 119 full-text articles were screened, and finally 34 trials were identified. Of these, liver-related adverse events were reported in four trials; these adverse events involved seven subjects (eight events) in the green tea intervention group and one subject (one event) in the control group. The summary odds ratio, estimated using a meta-analysis method for sparse event data, for intervention compared with placebo was 2.1 (95% confidence interval: 0.5–9.8). The few events reported in both groups were elevations of liver enzymes. Most were mild, and no serious liver-related adverse events were reported. Results of this review, although not conclusive, suggest that liver-related adverse events after intake of green tea extracts are expected to be rare. PMID:27188915

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

PubMed

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.

Irradiation application for color removal and purification of green tea leaves extract

NASA Astrophysics Data System (ADS)

Jo, Cheorun; Son, Jun Ho; Lee, Hyun Ja; Byun, Myung Woo

2003-02-01

Gamma irradiation was introduced to develop a new processing method for brighter-colored green tea leaves extract without changes of physiological activities. Dried green tea leaves were purchased and extracted by 70% ethanol solution and irradiated at 0, 5, 10, and 20 kGy with gamma rays. Hunter color L-value increased and a- and b-value decreased by irradiation, resulting in bright yellow from dark brown. There was no difference in radical scavenging and tyrosinase inhibition effect by irradiation. The irradiation effect in the solution disappeared during storage for 3 weeks at room temperature but vitamin C addition was effective in reducing the color change. Results indicated that irradiation may be a good technology to remove undesirable color in green tea leaves extract.

The effect of green, black and white tea on the level of alpha and gamma tocopherols in free radical-induced oxidative damage of human red blood cells.

PubMed

Gawlik, Małgorzata; Czajka, Aneta

2007-01-01

The present study was undertaken to investigate the effect of aqueous tea extracts on lipid peroxidation and alpha and gamma tocopherols concentration in the oxidative damage of human red blood cells (RBC). RBC was taken as the model for study of the oxidative damage was induced by cumene hydroperoxide (cumOOH). The antioxidative property of leaf green tea, leaf and granulate of black tea and white tea at levels 1, 2, 4 g/150 mL of water were evaluated. The correlation was observed between reducing power of tea extract and formation of malondialdehyde--MDA (an indicator of lipid peroxidation) in oxidative damage of RBC. All tea extracts at level of 4 g/150 mL of water significantly decreased concentration of MDA. The extract of green tea in comparison to black and white tea extracts at the same levels seems to be a better protective agent against oxidative stress. The antioxidant synergism between components extracted from leaves of green tea and endogenous alpha tocopherol in the oxidative damage of red blood cells was observed. The consumption of alpha tocopherol in oxidative damage of RBC was the lowest after treatment with the highest dose of green tea extract. All tea extracts did not protect against decrease of gamma tocopherol in human erythrocytes treated with cumOOH.

White Tea Extract Induces Apoptosis in Nonsmall Cell Lung Cancer Cells– The Role of PPAR-γ and 15-Lipoxygenases

PubMed Central

Mao, Jenny T.; Nie, Wen-Xian; Tsu, I-Hsien; Jin, Yu-Sheng; Rao, Jian yu; Lu, Qing-Yi; Zhang, Zuo-Feng; Go, Vay Liang W.; Serio, Kenneth J.

2010-01-01

Purpose Emerging preclinical data suggests that tea possess anticarcinogenic and antimutagenic properties. We therefore hypothesize that white tea extract (WTE) is capable of favorably modulating apoptosis, a mechanism associated with lung tumorigenesis. Experimental Design We examined the effects of physiologically relevant doses of WTE on the induction of apoptosis in the nonsmall cell lung cancer (NSCLC) cell lines, A549 (adenocarcinoma) and H520 (squamous cell carcinoma) cells. We further characterized the molecular mechanisms responsible for the WTE-induced apoptosis, including the induction of PPAR-γ and the 15-lipoxygenase (15-LOX) signaling pathway. Results We found that WTE was effective in inducing apoptosis in both A549 and H520 cells, and inhibition of PPAR-γ with GW 9662 partially reversed the WTE-induced apoptosis. We further demonstrate that WTE increased PPAR-γ activation and mRNA expression, concomitantly increased 15-HETE release, and up-regulated 15-LOX-1 and 2 mRNA expression by A549 cells. Inhibition of 15-LOX with NGDA, as well as caffeic acid, abrogated the WTE-induced PPAR-γ activation and up-regulation of PPAR-γ mRNA expression in A549 cells. WTE also induced cyclin-dependent kinase inhibitor 1A (CDKN1A) mRNA expression and activated caspase 3. Inhibition of caspase 3 abrogated the WTE-induced apoptosis. Conclusions Our findings indicate that WTE is capable of inducing apoptosis in NSCLC cell lines. The induction of apoptosis appears to be mediated, in part, through the up-regulation of the PPAR-γ and 15-LOX signaling pathways, with enhanced activation of caspase 3. Our findings support the future investigation of WTE as an antineoplastic and chemopreventive agent for lung cancer. PMID:20668019

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

NASA Astrophysics Data System (ADS)

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.

Tea-induced calmness: Sugar-sweetened tea calms consumers exposed to acute stressor

PubMed Central

Samant, Shilpa. S.; Wilkes, Katherine; Odek, Zephania; Seo, Han-Seok

2016-01-01

The food and beverage industry has been increasingly replacing sugar with non-nutritive sweeteners in their sweetened products to control or reduce total calories. Research comparing the effect of nutritive and non-nutritive sweeteners on emotional state of participants exposed to acute stressors is still limited. This study aimed to determine the effect of drinking tea sweetened with either a nutritive sweetener (sugar) or a non-nutritive sweetener (sucralose or stevia) on emotional state, in terms of calmness and pleasantness, of participants exposed to an acute stressor. Effects of acute stress on sweetness intensity and overall liking of tea beverages were also determined. Results showed that the possibility of tea-induced calmness, calculated as the difference between calmness ratings after and before drinking a tea sample, was established on stress session in the sugar-sweetened tea. Overall liking, but not the sweetness intensity, of the sugar-sweetened tea was affected by acute stress. In conclusion, this study provides empirical evidence that the consumption of tea sweetened with nutritive sweetener, but not with non-nutritive sweetener, has calming effect on consumers with acute stress, suggesting that this effect may not be due to the sweet taste of sugar, but due to the caloric nature of the sweetener. PMID:27848976

Tea-induced calmness: Sugar-sweetened tea calms consumers exposed to acute stressor.

PubMed

Samant, Shilpa S; Wilkes, Katherine; Odek, Zephania; Seo, Han-Seok

2016-11-16

The food and beverage industry has been increasingly replacing sugar with non-nutritive sweeteners in their sweetened products to control or reduce total calories. Research comparing the effect of nutritive and non-nutritive sweeteners on emotional state of participants exposed to acute stressors is still limited. This study aimed to determine the effect of drinking tea sweetened with either a nutritive sweetener (sugar) or a non-nutritive sweetener (sucralose or stevia) on emotional state, in terms of calmness and pleasantness, of participants exposed to an acute stressor. Effects of acute stress on sweetness intensity and overall liking of tea beverages were also determined. Results showed that the possibility of tea-induced calmness, calculated as the difference between calmness ratings after and before drinking a tea sample, was established on stress session in the sugar-sweetened tea. Overall liking, but not the sweetness intensity, of the sugar-sweetened tea was affected by acute stress. In conclusion, this study provides empirical evidence that the consumption of tea sweetened with nutritive sweetener, but not with non-nutritive sweetener, has calming effect on consumers with acute stress, suggesting that this effect may not be due to the sweet taste of sugar, but due to the caloric nature of the sweetener.

Lead induced oxidative stress: beneficial effects of Kombucha tea.

PubMed

Dipti, P; Yogesh, B; Kain, A K; Pauline, T; Anju, B; Sairam, M; Singh, B; Mongia, S S; Kumar, G Ilavazhagan Devendra; Selvamurthy, W

2003-09-01

To evaluate the effect of oral administration of Kombucha tea (K-tea) on lead induced oxidative stress. Sprague Dawley rats were administered 1 mL of 3.8% lead acetate solution daily alone or in combination with K-tea orally for 45 d, and the antioxidant status and lipid peroxidation were evaluated. Oral administration of lead acetate to rats enhanced lipid peroxidation and release of creatine phosphokinase and decreased levels of reduced glutathione (GSH) and antioxidant enzymes (superoxide dismutase, SOD and glutathione peroxidase, GPx). Lead treatment did not alter humoral immunity, but inhibited DTH response when compared to the control. Lead administration also increased DNA fragmentation in liver. Oral administration of Kombucha tea to rats exposed to lead decreased lipid peroxidation and DNA damage with a concomitant increase in the reduced glutathione level and GPx activity. Kombucha tea supplementation relieved the lead induced immunosuppression to appreciable levels. The results suggest that K-tea has potent antioxidant and immunomodulating properties.

Cancer prevention by green tea: evidence from epidemiologic studies.

PubMed

Yuan, Jian-Min

2013-12-01

In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral-digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made.

Exploring optimal supplement strategy of medicinal herbs and tea extracts for bioelectricity generation in microbial fuel cells.

PubMed

Chen, Bor-Yann; Liao, Jia-Hui; Hsu, An-Wei; Tsai, Po-Wei; Hsueh, Chung-Chuan

2018-05-01

This first-attempt study used extracts of appropriate antioxidant abundant Camellia and non-Camellia tea and medicinal herbs as model ESs to stably intensify bioelectricity generation performance in microbial fuel cells (MFCs). As electron shuttles (ESs) could stimulate electron transport phenomena by significant reduction of electron transfer resistance, the efficiency of power generation for energy extraction in microbial fuel cells (MFCs) could be appreciably augmented. Using environmentally friendly natural bioresource as green bioresource of ESs is the most promising to sustainable practicability. As comparison of power-density profiles indicated, supplement of Camellia tea extracts would be the most appropriate, then followed non-Camellia Chrysanthemum tea and medicinal herbs. Antioxidant activities, total phenolic contents and power stimulating activities were all electrochemically associated. In particular, the extract of unfermented Camellia tea (i.e., green tea) was the most promising ESs to augment bioenergy extraction compared to other refreshing medicinal herb extracts. Copyright © 2018 Elsevier Ltd. All rights reserved.

Metabolomics-Driven Nutraceutical Evaluation of Diverse Green Tea Cultivars

PubMed Central

Ida, Megumi; Kosaka, Reia; Miura, Daisuke; Wariishi, Hiroyuki; Maeda-Yamamoto, Mari; Nesumi, Atsushi; Saito, Takeshi; Kanda, Tomomasa; Yamada, Koji; Tachibana, Hirofumi

2011-01-01

Background Green tea has various health promotion effects. Although there are numerous tea cultivars, little is known about the differences in their nutraceutical properties. Metabolic profiling techniques can provide information on the relationship between the metabolome and factors such as phenotype or quality. Here, we performed metabolomic analyses to explore the relationship between the metabolome and health-promoting attributes (bioactivity) of diverse Japanese green tea cultivars. Methodology/Principal Findings We investigated the ability of leaf extracts from 43 Japanese green tea cultivars to inhibit thrombin-induced phosphorylation of myosin regulatory light chain (MRLC) in human umbilical vein endothelial cells (HUVECs). This thrombin-induced phosphorylation is a potential hallmark of vascular endothelial dysfunction. Among the tested cultivars, Cha Chuukanbohon Nou-6 (Nou-6) and Sunrouge (SR) strongly inhibited MRLC phosphorylation. To evaluate the bioactivity of green tea cultivars using a metabolomics approach, the metabolite profiles of all tea extracts were determined by high-performance liquid chromatography-mass spectrometry (LC-MS). Multivariate statistical analyses, principal component analysis (PCA) and orthogonal partial least-squares-discriminant analysis (OPLS-DA), revealed differences among green tea cultivars with respect to their ability to inhibit MRLC phosphorylation. In the SR cultivar, polyphenols were associated with its unique metabolic profile and its bioactivity. In addition, using partial least-squares (PLS) regression analysis, we succeeded in constructing a reliable bioactivity-prediction model to predict the inhibitory effect of tea cultivars based on their metabolome. This model was based on certain identified metabolites that were associated with bioactivity. When added to an extract from the non-bioactive cultivar Yabukita, several metabolites enriched in SR were able to transform the extract into a bioactive extract

Green Tea Leaves Extract: Microencapsulation, Physicochemical and Storage Stability Study.

PubMed

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.

Functional Characterization of Epitheaflagallin 3-O-Gallate Generated in Laccase-Treated Green Tea Extracts in the Presence of Gallic Acid.

PubMed

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.

Extraction and preparation of high-aroma and low-caffeine instant green teas by the novel column chromatographic extraction method with gradient elution.

PubMed

Li, Qing-Rong; Wu, Min; Huang, Rui-Jie; Chen, Ya-Fei; Chen, Chan-Jian; Li, Hui; Ni, He; Li, Hai-Hang

2017-06-01

The lack of aroma and natural taste is a critical problem in production and consumption of instant green teas. A method to prepare instant green teas high in-natural-aroma and low-caffeine by the novel column chromatographic extraction with gradient elution is reported. This method simultaneously extracted aroma (or volatile) and non-aroma compounds from green tea. Green tea was loaded into columns with 2.0-fold of petroleum ether (PE): ethanol (8:2). After standing for 3 h until the aroma compounds dissolved, the column was sequentially eluted with 3.0-fold 40% ethanol and 3.5-fold water. The eluant was collected together and automatically separated into PE and ethanol aqueous phases. The aroma extracts was obtained by vacuum-evaporation of PE phase at 45 °C. The ethanol aqueous phase was vacuum-concentrated to aqueous and partially or fully decaffeinated with 4% or 9% charcoal at 70 °C. A regular instant green tea with epigallocatechin-3-gallate: caffeine of 3.5:1 and a low-caffeine instant green tea (less than 1% caffeine) with excellent aroma and taste were prepared, by combining the aroma and non-aroma extracts at a 1:10 ratio. This work provides a practical approach to solve the low-aroma and low-taste problems in the production of high quality instant green teas.

Facile Separation of 5-O-Galloylquinic Acid from Chinese Green Tea Extract using Mesoporous Zirconium Phosphate.

PubMed

Ma, Yilong; Shang, Yafang; Zhu, Danye; Wang, Caihong; Zhong, Zhifeng; Xu, Ziyang

2016-05-01

5-O-Galloylquinic acid from green tea and other plants is attracting increasing attention for its antioxidant and antileishmanial bioactivities. It is always isolated using a silica column, a Sephadex column and high-performance liquid chromatography (HPLC) methods, which are either laborious or instrument dependent. To develop a new method to easily separate 5-O-galloylquinic acid. Mesoporous zirconium phosphate (m-ZrP) was prepared to conveniently separate 5-O-galloylquinic acid from Chinese green tea extract, and the target compound was easily obtained by simple steps of adsorption, washing and desorption. The effects of the green tea extraction conditions, extract concentrations, and m-ZrP adsorption/desorption dynamics on the 5-O-galloylquinic acid separation were evaluated. 5-O-Galloylquinic acid that was separated from a 70% ethanol extract of green tea was of moderate HPLC purity (92%) and recovery (88%), and an increased non-specific binding of epigallocatechin gallate (EGCG) on m-ZrP was observed in the diluted tea extract. The times for maximal adsorption of 5-O-galloylquinic acid in 70% ethanol extract and maximal desorption of 5-O-galloylquinic acid in 0.4% phosphoric acid solution were confirmed as 7 h and 5 h, respectively. A facile method to separate 5-O-galloylquinic acid from Chinese green tea extract using m-ZrP was established. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Fatty acid composition and antioxidant activity of tea (Camellia sinensis L.) seed oil extracted by optimized supercritical carbon dioxide.

PubMed

Wang, Yuefei; Sun, Da; Chen, Hao; Qian, Lisheng; Xu, Ping

2011-01-01

Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO(2)) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20-90 min), temperature (35-45 °C) and pressure (50-90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO(2) extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO(2) contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO(2) is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO(2) is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets.

Fatty Acid Composition and Antioxidant Activity of Tea (Camellia sinensis L.) Seed Oil Extracted by Optimized Supercritical Carbon Dioxide

PubMed Central

Wang, Yuefei; Sun, Da; Chen, Hao; Qian, Lisheng; Xu, Ping

2011-01-01

Seeds are another product in addition to leaves (raw materials for teas) of tea (Camellia sinensis L.) plant. The great increase of tea consumption in recent years raises the challenge of finding commercial applications for tea seeds. In the present study, supercritical carbon dioxide (SC-CO2) extraction edible oil from tea seed was carried out, response surface methodology (RSM) was used to optimize processing parameters including time (20–90 min), temperature (35–45 °C) and pressure (50–90 MPa). The fatty acid composition and antioxidant activity of the extracted oil was also investigated. The highest yield of oil (29.2 ± 0.6%) was obtained under optimal SC-CO2 extraction conditions (45 °C, 89.7 min and 32 MPa, respectively), which was significantly higher (p < 0.05) than that (25.3 ± 1.0%) given by Soxhlet extraction. Meanwhile, tea seed oil extracted by SC-CO2 contained approximately 80% unsaturated fatty acids and showed a much stronger scavenging ability on the DPPH radical than that extracted by Soxhlet. SC-CO2 is a promising alternative for efficient extraction of edible oil from tea seed. Moreover, tea seed oil extracted by SC-CO2 is highly edible and has good antioxidant activity, and therefore may play a potential role as a health-promoting food resource in human diets. PMID:22174626

Greener synthesis of magnetite nanoparticles using green tea extract and their magnetic properties

NASA Astrophysics Data System (ADS)

Karade, V. C.; Waifalkar, P. P.; Dongle, T. D.; Sahoo, Subasa C.; Kollu, P.; Patil, P. S.; Patil, P. B.

2017-09-01

The facile green synthesis method has been employed for the synthesis of biocompatible Fe3O4 magnetic nanoparticles (MNPs) using green tea extract. The effective reduction of ferric ions (Fe3+) were done using an aqueous green tea extract where it acts as reducing as well as capping agent. The effect of iron precursor to green tea extract ratio and reaction temperature was studied. The MNPs were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, field-emission scanning electron microscopy, dynamic light scattering and vibrating sample magnetometer. It was observed that the reaction temperature strongly affects the magnetic and structural properties of MNPs. The magnetic measurements study showed that Fe3O4 MNPs are superparamagnetic at 300 K, while at 60 K have ferromagnetic as well as superparamagnetic contributions.

Black tea extract and dental caries formation in hamsters.

PubMed

Linke, Harald A B; LeGeros, Racquel Z

2003-01-01

Several studies have suggested that green tea and Oolong tea extracts have antibacterial and anticariogenic properties in vitro and in vivo. The aim of the present study was to determine the effect of a standardized black tea extract (BTE) on caries formation in inbred hamsters on a regular and a cariogenic diet. Eighty hamsters were divided into four groups of 20 animals each. Two groups received a pelleted regular diet (LabChow) with water or BTE ad libitum. The other two groups received a powdered cariogenic diet (Diet 2000, containing 56% sucrose) with water or BTE ad libitum. The animals were kept for 3 months on their respective diets and then were sacrificed. The heads were retained, the jaws were prepared and stained using alizarin mordant red II, and were then scored for dental caries according to the Keyes method. This is the first study indicating that BTE, as compared with water, significantly decreased caries formation by 56.6% in hamsters on a regular diet and by 63.7% in hamsters on a cariogenic diet (P < 0.05). In the cariogenic diet group BTE, reduced the mandibular caries score of the hamsters slightly more than the maxillary caries score. The fluoride content of the standardized BTE solution was frequently monitored during the experiment; the mean fluoride concentration was found to be 4.22 ppm. A frequent intake of black tea can significantly decrease caries formation, even in the presence of sugars in the diet.

Comparison of Antioxidative Effects of Insect Tea and Its Raw Tea (Kuding Tea) Polyphenols in Kunming Mice.

PubMed

Zhao, Xin; Song, Jia-Le; Yi, Ruokun; Li, Guijie; Sun, Peng; Park, Kun-Young; Suo, Huayi

2018-01-19

Kudingcha is a traditional Chinese tea, and insect tea is a special drink produced by the metabolism of insect larvae using the raw Kuding tea. Insect tea polyphenols (ITP) and its raw tea (Kuding tea) polyphenols (KTP) are high-purity polyphenols extracted by centrifuge precipitation. The present study was designed to compare the antioxidative effects of insect tea polyphenols (ITP) and its raw tea (Kuding tea) polyphenols (KTP) on d-galactose-induced oxidation in Kunming (KM) mice. KM mice were treated with ITP (200 mg/kg) and KTP (200 mg/kg) by gavage, and vitamin C (VC, 200 mg/kg) was also used as a positive control by gavage. After determination in serum, liver and spleen, ITP-treated mice showed higher superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione (GSH) activities and lower nitric oxide (NO), malonaldehyde (MDA) activities than VC-treated mice, KTP-treated mice and untreated oxidation mice (control group). By H&E section observation, the mice induced by d-galactose-induced oxidation showed more changes than normal mice, and oxidative damage appeared in liver and spleen tissues; ITP, VC and KTP improved oxidative damage of liver and spleen tissues, and the effects of ITP were better than VC and KTP. Using quantitative polymerase chain reaction (qPCR) and western blot experiments, it was observed that ITP could increase the mRNA and protein expression of neuronal nitric oxide synthase (nNOS), endothelial nitric oxide synthase (eNOS), manganese superoxide dismutase (Mn-SOD), cupro/zinc superoxide dismutase (Cu/Zn-SOD), catalase (CAT), heme oxygenase-1 (HO-1), nuclear factor erythroid 2 related factor 2 (Nrf2), gamma glutamylcysteine synthetase (γ-GCS), and NAD(P)H:quinone oxidoreductase 1 (NQO1) and reduce inducible nitric oxide synthase (iNOS) expression in liver and spleen tissues compared to the control group. These effects were stronger than for VC and KTP. Both ITP and KTP had good antioxidative effects, and after the

Possible green tea-induced thrombotic thrombocytopenic purpura.

PubMed

Liatsos, George D; Moulakakis, Antonios; Ketikoglou, Ioannis; Klonari, Stella

2010-04-01

A case of a patient who developed thrombotic thrombocytopenic purpura (TTP) after consuming a weight-loss product containing green tea is reported. A 38-year-old, 68-kg Caucasian woman arrived at the emergency department with a one-week history of malaise, fatigue, and petechiae of the skin. She had no symptoms of infection and denied illegal drug use. Her medical history included hypothyroidism, for which she was treated with levothyroxine 150 microg daily for the past four years. She reported that she had been using a green tea preparation for the two months before admission to lose body weight. The daily preparation contained 200 mg of green tea extract 5:1, equivalent to 1 g of natural green tea. On clinical examination, the patient appeared acutely ill and was afebrile, with pallor, petechiae, and purpura of the extremities. Laboratory test results at the time of admission revealed that the patient had anemia and marked thrombocytopenia. A peripheral blood smear demonstrated a feature of microangiopathic hemolytic anemia. Immunoglobulin G autoantibodies against ADAM metallopeptidase with thrombospondin type 1 motif, 13 were detected. On hospital day 3, the patient appeared confused and exhibited aphasia that was initially transient but then recurrent. Brain computerized tomography did not exhibit focal pathology. Over the next few days, her neurologic symptoms subsided and her platelet count and hematocrit value gradually increased. Plasmapheresis was performed (12 procedures). Corticosteroid treatment was also initiated. After 20 days of hospitalization, the patient was discharged. A 38-year-old woman developed TTP after consuming a weight-loss product containing green tea extract for two months.

Evaluation of transfer rates of multiple pesticides from green tea into infusion using water as pressurized liquid extraction solvent and ultra-performance liquid chromatography tandem mass spectrometry.

PubMed

Chen, Hongping; Pan, Meiling; Liu, Xin; Lu, Chengyin

2017-02-01

Pesticide residues could be transferred from tea into its infusion and by-products, and subsequently consumed by humans. Extra extraction conditions may induce more pesticide leaching into the infusion and by-products of tea and cause greater damage to humans. The aim of this study is to evaluate the infusion of multiple pesticides from green tea into hot water via pressurized liquid extraction. The results showed that pesticides in spiked samples generally have higher leaching (0.8-45.0%) than those in the positive samples. There was a marked rise of transfer rates when water solubility increased from 20mgL(-1) to 450mgL(-1) and LogKow decreased from 6 to 4. All pesticides had more leaching into hot water using pressurized liquid extraction than traditional tea brewing. This study helps in risk assessment of pesticide residues and in the formulation of maximum residue levels (MRLs) in tea and its by-products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Green Tea Potentially Ameliorates Bisphenol A-Induced Oxidative Stress: An In Vitro and In Silico Study

PubMed Central

Suthar, Hiral; Verma, R. J.; Patel, Saumya; Jasrai, Y. T.

2014-01-01

The present investigation was an attempt to elucidate oxidative stress induced by bisphenol A on erythrocytes and its amelioration by green tea extract. For this, venous blood samples from healthy human adults were collected in EDTA vials and used for preparation of erythrocytes suspension. When erythrocyte suspensions were treated with different concentrations of BPA/H2O2, a dose-dependent increase in hemolysis occurred. Similarly, when erythrocytes suspensions were treated with either different concentrations of H2O2 (0.05–0.25 mM) along with BPA (50 μg/mL) or 0.05 mM H2O2 along with different concentrations of BPA (50–250 μg/mL), dose-dependent significant increase in hemolysis occurred. The effect of BPA and H2O2 was found to be additive. For the confirmation, binding capacity of bisphenol A with erythrocyte proteins (hemoglobin, catalase, and glutathione peroxidase) was inspected using molecular docking tool, which showed presence of various hydrogen bonds of BPA with the proteins. The present data clearly indicates that BPA causes oxidative stress in a similar way as H2O2 . Concurrent addition of different concentrations (10–50 μg/mL) of green tea extract to reaction mixture containing high dose of bisphenol A (250 μg/mL) caused concentration-dependent amelioration in bisphenol A-induced hemolysis. The effect was significant (P < 0.05). It is concluded that BPA-induced oxidative stress could be significantly mitigated by green tea extract. PMID:25180096

Potential mechanisms for the effects of tea extracts on the attachment, biofilm formation and cell size of Streptococcus mutans.

PubMed

Wang, Yi; Lee, Sui M; Dykes, Gary A

2013-01-01

Tea can inhibit the attachment of Streptococcus mutans to surfaces and subsequent biofilm formation. Five commercial tea extracts were screened for their ability to inhibit attachment and biofilm formation by two strains of S. mutans on glass and hydroxyapatite surfaces. The mechanisms of these effects were investigated using scanning electron microscopy (SEM) and phytochemical screening. The results indicated that extracts of oolong tea most effectively inhibited attachment and extracts of pu-erh tea most effectively inhibited biofilm formation. SEM images showed that the S. mutans cells treated with extracts of oolong tea, or grown in medium containing extracts of pu-erh tea, were coated with tea components and were larger with more rounded shapes. The coatings on the cells consisted of flavonoids, tannins and indolic compounds. The ratio of tannins to simple phenolics in each of the coating samples was ∼3:1. This study suggests potential mechanisms by which tea components may inhibit the attachment and subsequent biofilm formation of S. mutans on tooth surfaces, such as modification of cell surface properties and blocking of the activity of proteins and the structures used by the bacteria to interact with surfaces.

Hepatoprotective and curative properties of Kombucha tea against carbon tetrachloride-induced toxicity.

PubMed

Murugesan, G S; Sathishkumar, M; Jayabalan, R; Binupriya, A R; Swaminathan, K; Yun, S E

2009-04-01

Kombucha tea (KT) is sugared black tea fermented with a symbiotic culture of acetic acid bacteria and yeasts, which is said to be tea fungus. KT is claimed to have various beneficial effects on human health, but there is very little scientific evidence available in the literature. In the present study, KT along with black tea (BT) and black tea manufactured with tea fungus enzymes (enzyme-processed tea, ET) was evaluated for hepatoprotective and curative properties against CCl4-induced toxicity, using male albino rats as an experimental model by analyzing aspartate transaminase, alanine transaminase, and alkaline phosphatase in plasma and malondialdehyde content in plasma and liver tissues. Histopathological analysis of liver tissue was also included. Results showed that BT, ET, and KT have the potential to revert the CCl4-induced hepatotoxicity. Among the three types of teas tried, KT was found to be more efficient than BT and ET. Antioxidant molecules produced during the fermentation period could be the reason for the efficient hepatoprotective and curative properties of KT against CCI4-induced hepatotoxicity.

Green synthesis of iron nanoparticles by various tea extracts: comparative study of the reactivity.

PubMed

Huang, Lanlan; Weng, Xiulan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravendra

2014-09-15

Iron nanoparticles (Fe NPs) are often synthesized using sodium borohydride with aggregation, which is a high cost process and environmentally toxic. To address these issues, Fe NPs were synthesized using green methods based on tea extracts, including green, oolong and black teas. The best method for degrading malachite green (MG) was Fe NPs synthesized by green tea extracts because it contains a high concentration of caffeine/polyphenols which act as both reducing and capping agents in the synthesis of Fe NPs. These characteristics were confirmed by a scanning electron microscope (SEM), UV-visible (UV-vis) and specific surface area (BET). To understand the formation of Fe NPs using various tea extracts, the synthesized Fe NPs were characterized by SEM, X-ray energy-dispersive spectrometer (EDS), and X-ray diffraction (XRD). What emerged were different sizes and concentrations of Fe NPs being synthesized by tea extracts, leading to various degradations of MG. Furthermore, kinetics for the degradation of MG using these Fe NPs fitted well to the pseudo first-order reaction kinetics model with more than 20 kJ/mol activation energy, suggesting a chemically diffusion-controlled reaction. The degradation mechanism using these Fe NPs included adsorption of MG to Fe NPs, oxidation of iron, and cleaving the bond that was connected to the benzene ring. Copyright © 2014 Elsevier B.V. All rights reserved.

The Peroxidation of Leukocytes Index Ratio Reveals the Prooxidant Effect of Green Tea Extract

PubMed Central

Manafikhi, Husseen; Raguzzini, Anna; Longhitano, Yaroslava; Reggi, Raffaella; Zanza, Christian

2016-01-01

Despite tea increased plasma nonenzymatic antioxidant capacity, the European Food Safety Administration (EFSA) denied claims related to tea and its protection from oxidative damage. Furthermore, the Supplement Information Expert Committee (DSI EC) expressed some doubts on the safety of green tea extract (GTE). We performed a pilot study in order to evaluate the effect of a single dose of two capsules of a GTE supplement (200 mg × 2) on the peroxidation of leukocytes index ratio (PLIR) in relation to uric acid (UA) and ferric reducing antioxidant potential (FRAP), as well as the sample size to reach statistical significance. GTE induced a prooxidant effect on leukocytes, whereas FRAP did not change, in agreement with the EFSA and the DSI EC conclusions. Besides, our results confirm the primary role of UA in the antioxidant defences. The ratio based calculation of the PLIR reduced the sample size to reach statistical significance, compared to the resistance to an exogenous oxidative stress and to the functional capacity of oxidative burst. Therefore, PLIR could be a sensitive marker of redox status. PMID:28101300

The Peroxidation of Leukocytes Index Ratio Reveals the Prooxidant Effect of Green Tea Extract.

PubMed

Peluso, Ilaria; Manafikhi, Husseen; Raguzzini, Anna; Longhitano, Yaroslava; Reggi, Raffaella; Zanza, Christian; Palmery, Maura

2016-01-01

Despite tea increased plasma nonenzymatic antioxidant capacity, the European Food Safety Administration (EFSA) denied claims related to tea and its protection from oxidative damage. Furthermore, the Supplement Information Expert Committee (DSI EC) expressed some doubts on the safety of green tea extract (GTE). We performed a pilot study in order to evaluate the effect of a single dose of two capsules of a GTE supplement (200 mg × 2) on the peroxidation of leukocytes index ratio (PLIR) in relation to uric acid (UA) and ferric reducing antioxidant potential (FRAP), as well as the sample size to reach statistical significance. GTE induced a prooxidant effect on leukocytes, whereas FRAP did not change, in agreement with the EFSA and the DSI EC conclusions. Besides, our results confirm the primary role of UA in the antioxidant defences. The ratio based calculation of the PLIR reduced the sample size to reach statistical significance, compared to the resistance to an exogenous oxidative stress and to the functional capacity of oxidative burst. Therefore, PLIR could be a sensitive marker of redox status.

[Study on extraction process of available components of tea].

PubMed

Bai, Qing-Qing; Liu, Yong-Feng; Guo, Mei; Zhao, Jian-Xi; Zhang, Tian-Cai; Di, Duo-Long

2011-09-01

To investigate the optimum ethanol extraction process conditions for the available components in the tea - Catechines (CT) including Epigallo catechin gallate (EGCG) and Caffeine (CF). The content of EGCG, CT and CF, extraction rate, DPPH * Free radical scavenging capacity were chosen as the assessment indexes. With the alcohol ratio (A), solid-liquid ratio (B) and reflux time (C) as investigation factors, the optimum ethanol extraction process of the available components from tea was determined by L9 (3(4)) orthogonal experimental design. It would obtain different extraction conditions to analyze the assessment indexes depending on the different extraction purposes. For the purpose of CT, the contents of EGCG and CT, extraction rate and DPPH * Free radical scavenging capacity were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 75% alcohol was 1: 12, the reflux time was 30 minutes and extraction times were three; For the purpose of CF, the content of CF and extraction rate were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 60% alcohol was 1: 12, the reflux time was 30 minutes and extraction times were three; For the purpose of integrated extraction, the contents of CT and CF, extraction rate and DPPH * Free radical scavenging capacity were chosen as the assessment indexes, the optimum extraction conditions were selected as follows: the ratio of raw material to 60% alcohol was 1: 8, the reflux time was 30 minutes and extraction times were three. The optimum extraction process in order to attain different purposes can give a reference to the research of a new medicine and industry production.

Evaluation of the effect of green tea extract on mouth bacterial activity in the presence of propylene glycol.

PubMed

Moghbel, Abdolhossein; Farjzadeh, Ahmad; Aghel, Nasrin; Agheli, Homaun; Raisi, Nafiseh

2012-01-01

Compounds present in green tea have proved to inhibit the growth and activity of bacteria associated with infections. To assess the effects of green tea leaves extract in presence of propylene glycol on the aerobic mouth bacteria load. Saliva of 25 volunteer girl students aging 20-25 years were selected and evaluated by a mouthwash sample containing 1% tannin, as the most effective antibacterial complex in green tea. Comparative studies were also conducted between green tea mouthwashes containing 1% tannin and a similar sample with 10% propylene glycol added during extraction. This comparison was applied for a chlorhexidine 0.2% sample as a chemical mouthwash brand, too. There was a meaningful difference between the green tea mouthwashes containing 10% propylene glycol and the simple green tea extract (P < 0.05). Significant difference was also seen between the herbal and chemical mouthwashes (P < 0.05). The extract 1% tannin containing 10% propylene glycol reduced the aerobic mouth bacterial load of the student salvia about 64 percent. The pH monotonousness in different days and temperatures approved the stability of tannin in liquid water medium. Using green tea extract as a herbal mouthwash is safe and harmless specially for children and pregnant women. This result led us to suppose that green tea may prevent plaque formation on teeth, coming over halitosis due to mouth infection, too. These effects need to be approved in an in vivo trial as a second study.

High antiviral effects of hibiscus tea extract on the H5 subtypes of low and highly pathogenic avian influenza viruses

PubMed Central

BAATARTSOGT, Tugsbaatar; BUI, Vuong N.; TRINH, Dai Q.; YAMAGUCHI, Emi; GRONSANG, Dulyatad; THAMPAISARN, Rapeewan; OGAWA, Haruko; IMAI, Kunitoshi

2016-01-01

Viral neuraminidase inhibitors are widely used as synthetic anti-influenza drugs for the prevention and treatment of influenza. However, drug-resistant influenza A virus variants, including H5N1 highly pathogenic avian influenza viruses (HPAIVs), have been reported. Therefore, the discovery of novel and effective antiviral agents is warranted. We screened the antiviral effects of 11 herbal tea extracts (hibiscus, black tea, tencha, rosehip tea, burdock tea, green tea, jasmine tea, ginger tea, lavender tea, rose tea and oak tea) against the H5N1 HPAIV in vitro. Among the tested extracts, only the hibiscus extract and its fractionated extract (frHibis) highly and rapidly reduced the titers of all H5 HPAIVs and low pathogenic AIVs (LPAIVs) used in the pre-treatment tests of Madin–Darby canine kidney (MDCK) cells that were inoculated with a mixture of the virus and the extract. Immunogold electron microscopy showed that anti-H5 monoclonal antibodies could not bind to the deformed H5 virus particles pretreated with frHibis. In post-treatment tests of MDCK cells cultured in the presence of frHibis after infection with H5N1 HPAIV, the frHibis inhibited viral replication and the expression of viral antigens and genes. Among the plants tested, hibiscus showed the most prominent antiviral effects against both H5 HPAIV and LPAIV. PMID:27193820

High antiviral effects of hibiscus tea extract on the H5 subtypes of low and highly pathogenic avian influenza viruses.

PubMed

Baatartsogt, Tugsbaatar; Bui, Vuong N; Trinh, Dai Q; Yamaguchi, Emi; Gronsang, Dulyatad; Thampaisarn, Rapeewan; Ogawa, Haruko; Imai, Kunitoshi

2016-10-01

Viral neuraminidase inhibitors are widely used as synthetic anti-influenza drugs for the prevention and treatment of influenza. However, drug-resistant influenza A virus variants, including H5N1 highly pathogenic avian influenza viruses (HPAIVs), have been reported. Therefore, the discovery of novel and effective antiviral agents is warranted. We screened the antiviral effects of 11 herbal tea extracts (hibiscus, black tea, tencha, rosehip tea, burdock tea, green tea, jasmine tea, ginger tea, lavender tea, rose tea and oak tea) against the H5N1 HPAIV in vitro. Among the tested extracts, only the hibiscus extract and its fractionated extract (frHibis) highly and rapidly reduced the titers of all H5 HPAIVs and low pathogenic AIVs (LPAIVs) used in the pre-treatment tests of Madin-Darby canine kidney (MDCK) cells that were inoculated with a mixture of the virus and the extract. Immunogold electron microscopy showed that anti-H5 monoclonal antibodies could not bind to the deformed H5 virus particles pretreated with frHibis. In post-treatment tests of MDCK cells cultured in the presence of frHibis after infection with H5N1 HPAIV, the frHibis inhibited viral replication and the expression of viral antigens and genes. Among the plants tested, hibiscus showed the most prominent antiviral effects against both H5 HPAIV and LPAIV.

Antimutagenicity and catechin content of soluble instant teas.

PubMed

Constable, A; Varga, N; Richoz, J; Stadler, R H

1996-03-01

The antimutagenic properties of soluble instant teas were examined using the bacterial Ames assay. Inhibition of the numbers of revertants induced from a number of known mutagens indicates that aqueous extracts of instant teas have antimutagenic activity and antioxidative properties, and can inhibit nitrosation reactions. Despite a significant reduction in the amounts of major green tea catechins, quantified using reversed-phase HPLC with electro-chemical detection, no differences in antimutagenicity were observed between the instant teas, a black fermented tea and a green tea. Oxidation of polyphenolic compounds which occurs during the production of instant tea does not therefore decrease the antioxidant, free radical scavenging and antimutagenic properties. This suggests that catechins are not the only compounds responsible for the protective effects of teas.

Xerophilic aflatoxigenic black tea fungi and their inhibition by Elettaria cardamomum and Syzygium aromaticum extracts

PubMed Central

Al-Sohaibani, Saleh; Murugan, K.; Lakshimi, G.; Anandraj, K.

2011-01-01

Black tea is consumed worldwide and is believed to play a role in cancer prevention. Xerophilic aflatoxigenic fungi are highly hazardous contaminants of tea since they are associated with tea quality impairment and human health risk. The present study reports isolation of such xerophilic and aflatoxigenic fungi associated with marketed tea. Twenty different tea samples collected from the local markets of Tamilnadu, India were investigated for fungal contamination. The results indicated contamination by 0.38% Aspergillus flavus. Other common contaminant fungi including Penicillium spp. (0.30%), Pacelomyces spp. (0.14%), and Mucor spp. (0.19%) were also isolated. Amongst the fungi isolated Aspergillus niger ML01 and A. flavus ML02 were found to be xerophilic aflatoxigenic mycoflora. Phylogenetic analysis based on 28S rRNA revealed their close ancestry. The chloroform and acetone extracts of spices Elettaria cardamomum and Syzygium aromaticum exhibited antifungal inhibitory activity on growth and toxin elaboration of both these xerophilic tea contaminants A. niger ML01 and A. flavus ML02. The results advocate the use of these spices plant or their extracts as novel antimicrobials which may add preservation and flavour in marketed tea. PMID:23961151

Artificial neural network modeling and optimization of ultrahigh pressure extraction of green tea polyphenols.

PubMed

Xi, Jun; Xue, Yujing; Xu, Yinxiang; Shen, Yuhong

2013-11-01

In this study, the ultrahigh pressure extraction of green tea polyphenols was modeled and optimized by a three-layer artificial neural network. A feed-forward neural network trained with an error back-propagation algorithm was used to evaluate the effects of pressure, liquid/solid ratio and ethanol concentration on the total phenolic content of green tea extracts. The neural network coupled with genetic algorithms was also used to optimize the conditions needed to obtain the highest yield of tea polyphenols. The obtained optimal architecture of artificial neural network model involved a feed-forward neural network with three input neurons, one hidden layer with eight neurons and one output layer including single neuron. The trained network gave the minimum value in the MSE of 0.03 and the maximum value in the R(2) of 0.9571, which implied a good agreement between the predicted value and the actual value, and confirmed a good generalization of the network. Based on the combination of neural network and genetic algorithms, the optimum extraction conditions for the highest yield of green tea polyphenols were determined as follows: 498.8 MPa for pressure, 20.8 mL/g for liquid/solid ratio and 53.6% for ethanol concentration. The total phenolic content of the actual measurement under the optimum predicated extraction conditions was 582.4 ± 0.63 mg/g DW, which was well matched with the predicted value (597.2mg/g DW). This suggests that the artificial neural network model described in this work is an efficient quantitative tool to predict the extraction efficiency of green tea polyphenols. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Identification of Key Odorants in Withering-Flavored Green Tea by Aroma Extract Dilution Analysis

NASA Astrophysics Data System (ADS)

Mizukami, Yuzo; Yamaguchi, Yuichi

This research aims to identify key odorants in withering-flavored green tea. Application of the aroma extract dilution analysis using the volatile fraction of green tea and withering-flavored green tea revealed 25 and 35 odor-active peaks with the flavor dilution factors of≥4, respectively. 4-mercapto-4-methylpentan-2-one, (E)-2-nonenal, linalool, (E,Z)-2,6-nonadienal and 3-methylnonane-2,4-dione were key odorants in green tea with the flavor dilution factor of≥16. As well as these 5 odorants, 1-octen-3-one, β-damascenone, geraniol, β-ionone, (Z)-methyljasmonate, indole and coumarine contributed to the withering flavor of green tea.

Evaluation of the Effect of Green Tea Extract on Mouth Bacterial Activity in the Presence of Propylene Glycol

PubMed Central

Moghbel, Abdolhossein; Farjzadeh, Ahmad; Aghel, Nasrin; Agheli, Homaun; Raisi, Nafiseh

2012-01-01

Background Compounds present in green tea have proved to inhibit the growth and activity of bacteria associated with infections. Objectives To assess the effects of green tea leaves extract in presence of propylene glycol on the aerobic mouth bacteria load. Materials and Methods Saliva of 25 volunteer girl students aging 20-25 years were selected and evaluated by a mouthwash sample containing 1% tannin, as the most effective antibacterial complex in green tea. Comparative studies were also conducted between green tea mouthwashes containing 1% tannin and a similar sample with 10% propylene glycol added during extraction. This comparison was applied for a chlorhexidine 0.2% sample as a chemical mouthwash brand, too. Results There was a meaningful difference between the green tea mouthwashes containing 10% propylene glycol and the simple green tea extract (P < 0.05). Significant difference was also seen between the herbal and chemical mouthwashes (P < 0.05). The extract 1% tannin containing 10% propylene glycol reduced the aerobic mouth bacterial load of the student salvia about 64 percent. The pH monotonousness in different days and temperatures approved the stability of tannin in liquid water medium. Conclusions Using green tea extract as a herbal mouthwash is safe and harmless specially for children and pregnant women. This result led us to suppose that green tea may prevent plaque formation on teeth, coming over halitosis due to mouth infection, too. These effects need to be approved in an in vivo trial as a second study. PMID:24624155

The enhanced inhibition of water extract of black tea under baking treatment on α-amylase and α-glucosidase.

PubMed

Tong, Da-Peng; Zhu, Ke-Xue; Guo, Xiao-Na; Peng, Wei; Zhou, Hui-Ming

2018-02-01

This paper studied the inhibition of water extract of natural or baked black tea on the activity of α-amylase and α- glucosidase. Baking treatment was found to be one effective way to enhance the inhibition of black tea on both α-amylase and α- glucosidase, and IC 50 of water extract of baked black tea (BBTWE) were 1.213mg/mL and 4.190mg/mL, respectively, while IC 50 of water extract of black tea (BTWE) were 1.723mg/mL and 6.056mg/mL, respectively. This study further studied the mechanism of the effect of water extract on α-amylase and α- glucosidase using HPLC, circular dichroism, and synchronous fluorescence. HPLC analysis of tea polyphenols showed that the content of tea polyphenols with low polarity increased after baking. In addition, BBTWE had higer abilty on decreasing the hydrophobicity of tryptophan residues than BTWE for both α-amylase and α- glucosidase.The increase of α-helix proportion of α-amylase when treated with BBTWE was more obvious than that when treated with BTWE. In a word, thermal process of baked foods may be beneficial for tea polyphenols to reduce the rate of starch digestion. Copyright © 2017 Elsevier B.V. All rights reserved.

Labrador tea (Rhododendron groenlandicum) attenuates insulin resistance in a diet-induced obesity mouse model.

PubMed

Ouchfoun, Meriem; Eid, Hoda M; Musallam, Lina; Brault, Antoine; Li, Shilin; Vallerand, Diane; Arnason, John T; Haddad, Pierre S

2016-04-01

Using a diet-induced obesity (DIO) mouse model, we investigated the antidiabetic effect of Labrador tea [Rhododendron groenlandicum (Oeder) Kron and Judd], a beverage and medicinal tea used by the Cree Nations of northern Quebec. C57BL6 mice were divided into five groups and given standard chow (~4 % of lipids) or high-fat diet (~35 % of lipids) for 8 weeks until they became obese and insulin resistant. Treatment began by adding the plant extract at three doses (125, 250 and 500 mg/kg) to the high-fat diet for another 8 weeks. At the end of the study, insulin-sensitive tissues (liver, skeletal muscle, adipose tissue) were collected to investigate the plant's molecular mechanisms. Labrador tea significantly reduced blood glucose (13 %), the response to an oral glucose tolerance test (18.2 %) and plasma insulin (65 %) while preventing hepatic steatosis (42 % reduction in hepatic triglyceride levels) in DIO mice. It stimulated insulin-dependent Akt pathway (55 %) and increased the expression of GLUT4 (53 %) in skeletal muscle. In the liver, Labrador tea stimulated the insulin-dependent Akt and the insulin-independent AMP-activated protein kinase pathways. The improvement in hepatic steatosis observed in DIO-treated mice was associated with a reduction in inflammation (through the IKK α/β) and a decrease in the hepatic content of SREBP-1 (39 %). Labrador tea exerts potential antidiabetic action by improving insulin sensitivity and mitigating high-fat diet-induced obesity and hyperglycemia. They validate the safety and efficacy of this plant, a promising candidate for culturally relevant complementary treatment in Cree diabetics.

Highly Selective and Considerable Subcritical Butane Extraction to Separate Abamectin in Green Tea.

PubMed

Zhang, Yating; Gu, Lingbiao; Wang, Fei; Kong, Lingjun; Pang, Huili; Qin, Guangyong

2017-06-01

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. The results showed that the extraction temperature was the uppermost parameter compared with others. The optimal extraction conditions selected as follows: extraction temperature, 42°C; number of extraction cycles and extraction time, 1 and 30 min, respectively; and solid-liquid ratio, 1:10. Based on the above study, the separation efficiency of abamectin was up to 93.95%. It is notable that there has a quite low loss rate, including the negligible damage of aroma components, the bits reduce of catechins within the range of 0.7%-13.1%, and a handful lessen of caffeine and theanine of 1.81% and 2.6%, respectively. The proposed method suggested subcritical butane possesses solubility for lipid-soluble pesticides, and since most of the pesticides are attached to the surfaces of tea, thus the as-applied method was successfully effective to separate abamectin because of the so practical and promising method.

Extraction of Epigallocatechin Gallate and Epicatechin Gallate from Tea Leaves Using β-Cyclodextrin.

PubMed

Cui, Lu; Liu, Yuxuan; Liu, Ting; Yuan, Yahong; Yue, Tianli; Cai, Rui; Wang, Zhouli

2017-02-01

Use of organic solvents to extract phenolic compounds from plants may result in environmental pollution and cause health problems in persons. Replacing organic extraction solvents by green extracting agents without affecting the extraction yield is one of the most pressing problems to be solved. The aim of this study is to evaluate the capacity of β-cyclodextrin (β-CD) to recover phenolic compounds from tea leaves. The extract obtained using the ethanol/water mixture presented the highest total phenolic content, followed by those obtained using β-CD solution and water. HPLC analysis of the extracts showed that the addition of β-CD to the extracting agent had a selective effect on the extraction of epigallocatechin gallate (EGCG) and epicatechin gallate (ECG). The extraction yield of EGCG and ECG using 15 g/L β-CD were higher than that obtained using water and 50% ethanol. Molecular docking results indicated that the molecules of EGCG and ECG were more inclined to interact with β-CD than epigallocatechin, epicatechin, and gallocatechin. The impact of β-CD concentration, temperature, and time on EGCG and ECG extraction from tea leaves was investigated and the maximum amount of EGCG (118.7 mg/g) and ECG (54.6 mg/g) were achieved when extracted with 25 g/L aqueous β-CD solution at 60 °C for 60 min. The present study indicates that aqueous β-CD can be used as an alternative to organic solvents to recover EGCG and ECG from tea leaves. © 2017 Institute of Food Technologists®.

Aroma changes of black tea prepared from methyl jasmonate treated tea plants*

PubMed Central

Shi, Jiang; Wang, Li; Ma, Cheng-ying; Lv, Hai-peng; Chen, Zong-mao; Lin, Zhi

2014-01-01

Methyl jasmonate (MeJA) was widely applied in promoting food quality. Aroma is one of the key indicators in judging the quality of tea. This study examined the effect of exogenous MeJA treatment on tea aroma. The aroma components in black tea prepared from MeJA-treated fresh tea leaves were extracted using headspace solid-phase microextraction (HS-SPME) and were analyzed using gas chromatography-mass spectrometry (GC-MS) and GC-olfactometry (GC-O). Forty-five volatile compounds were identified. The results revealed that the MeJA-treated black tea had higher levels of terpene alcohols and hexenyl esters than the untreated tea. Moreover, several newly components, including copaene, cubenol, and indole, were induced by the MeJA treatment. The activities of polyphenol oxidase and β-glucosidase in fresh tea leaves changed after the MeJA treatment. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis indicated that the gene expression levels of polyphenol oxidase and β-primeverosidase were upregulated by two and three folds, respectively, by the MeJA treatment (P<0.01); however, the gene expression of β-glucosidase was downregulated to a half level. In general, the aroma quality of the MeJA-treated black tea was clearly improved. PMID:24711352

Antioxidant activities of distiller dried grains with solubles as protein films containing tea extracts and their application in the packaging of pork meat.

PubMed

Yang, Hyun-Ju; Lee, Ji-Hyeon; Won, Misun; Song, Kyung Bin

2016-04-01

Distiller dried grains with solubles (DDGS) as protein (DP) films were prepared. Additionally, to prepare anti-oxidant films, green tea extract (GTE), oolong tea extract (OTE), and black tea extract (BTE) were incorporated into the DP films. Consequently, the incorporation of the tea extracts did not alter the physical properties of the films much, whereas the antioxidant activities, such as ABTS and DPPH radical scavenging activities were observed. To apply the DP films containing tea extracts to food packaging, pork meat was wrapped with the films and stored at 4 °C for 10 d. During storage, the pork meat wrapped with the DP films containing GTE, OTE, and BTE had less lipid oxidation than did the control. Among the tea extracts, the DP film containing GTE had the greatest antioxidant activity. These results indicate that the DP films containing green tea extracts can be utilized as an anti-oxidative packaging material for pork meat. Copyright © 2015 Elsevier Ltd. All rights reserved.

Further investigation of the biosynthesis of caffeine in tea plants (Camellia sinensis L.). Methylation of transfer ribonucleic acid by tea leaf extracts.

PubMed Central

Suzuki, T; Takahashi, E

1976-01-01

1. The tRNA methyltransferase activity in vitro of leaves, cotyledons and roots of 85-day-old tea seedlings was studied. 2. The activity of extracts prepared from tea leaves with Polycar AT (insoluble polyvinylpyrrolidine) had optimum pH7.7 and was greatly influenced by thiol compounds, but only slightly by metal ions and ammonium acetate. 3. The activities of extracts, expressed per mg of protein, were as follows: roots greater than leaves greater than cotyledons. The only methylated base isolated after incubation with these preparations was 1-methyladenine. 4. The results did not support the view of involvement of methylation of nucleic acids in caffeine biosynthesis in tea plants. In contrast, it is suggested that theophylline is synthesized from the specific methylated precursor in nucleic acids, namely 1-methyladenylic acid, via 1-methylxanthine. PMID:12749

The safety of green tea and green tea extract consumption in adults - Results of a systematic review.

PubMed

Hu, Jiang; Webster, Donna; Cao, Joyce; Shao, Andrew

2018-06-01

A systematic review of published toxicology and human intervention studies was performed to characterize potential hazards associated with consumption of green tea and its preparations. A review of toxicological evidence from laboratory studies revealed the liver as the target organ and hepatotoxicity as the critical effect, which was strongly associated with certain dosing conditions (e.g. bolus dose via gavage, fasting), and positively correlated with total catechin and epigallocatechingallate (EGCG) content. A review of adverse event (AE) data from 159 human intervention studies yielded findings consistent with toxicological evidence in that a limited range of concentrated, catechin-rich green tea preparations resulted in hepatic AEs in a dose-dependent manner when ingested in large bolus doses, but not when consumed as brewed tea or extracts in beverages or as part of food. Toxico- and pharmacokinetic evidence further suggests internal dose of catechins is a key determinant in the occurrence and severity of hepatotoxicity. A safe intake level of 338 mg EGCG/day for adults was derived from toxicological and human safety data for tea preparations ingested as a solid bolus dose. An Observed Safe Level (OSL) of 704 mg EGCG/day might be considered for tea preparations in beverage form based on human AE data. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

The Effect of LAB as Probiotic Starter Culture and Green Tea Extract Addition on Dry Fermented Pork Loins Quality.

PubMed

Neffe-Skocińska, Katarzyna; Jaworska, Danuta; Kołożyn-Krajewska, Danuta; Dolatowski, Zbigniew; Jachacz-Jówko, Luiza

2015-01-01

The objective of this study was to evaluate the microbiological, physicochemical, and sensory quality of dry fermented pork loin produced with the addition of Lb. rhamnosus LOCK900 probiotic strain, 0.2% glucose, and 1.5% green tea extract. Three loins were prepared: control sample (P0: no additives), sample supplemented with glucose and probiotic strain (P1), and sample with glucose, green tea extract, and probiotic (P2). The samples were analyzed after 21 days of ripening and 180 days of storage. The results indicated that the highest count of LAB was observed both in the samples: with probiotic and with probiotic and green tea extract (7.00 log cfu/g after ripening; 6.00 log cfu/g after storage). The oxidation-reduction potential values were lower in the probiotic loin samples. Probiotic and green tea extract have not caused color changes of study loins during storage. The study demonstrated that an addition of probiotic and green tea extract to dry fermented loins is possible and had no impact on sensory quality after product storage.

The Effect of LAB as Probiotic Starter Culture and Green Tea Extract Addition on Dry Fermented Pork Loins Quality

PubMed Central

Jaworska, Danuta; Kołożyn-Krajewska, Danuta; Dolatowski, Zbigniew; Jachacz-Jówko, Luiza

2015-01-01

The objective of this study was to evaluate the microbiological, physicochemical, and sensory quality of dry fermented pork loin produced with the addition of Lb. rhamnosus LOCK900 probiotic strain, 0.2% glucose, and 1.5% green tea extract. Three loins were prepared: control sample (P0: no additives), sample supplemented with glucose and probiotic strain (P1), and sample with glucose, green tea extract, and probiotic (P2). The samples were analyzed after 21 days of ripening and 180 days of storage. The results indicated that the highest count of LAB was observed both in the samples: with probiotic and with probiotic and green tea extract (7.00 log cfu/g after ripening; 6.00 log cfu/g after storage). The oxidation-reduction potential values were lower in the probiotic loin samples. Probiotic and green tea extract have not caused color changes of study loins during storage. The study demonstrated that an addition of probiotic and green tea extract to dry fermented loins is possible and had no impact on sensory quality after product storage. PMID:25961018

In-vitro study investigating influence of toothpaste containing green tea extract on the microhardness of demineralized human enamel

NASA Astrophysics Data System (ADS)

Febrian, K.; Triaminingsih, S.; Indrani, DJ

2017-08-01

The aim of this study was to analyze the influence of toothpaste containing green tea extract on the microhardness of demineralized enamel. Human tooth, which was demineralised in citric acid solution, had a toothpaste containing green tea extract of concentration of 5, 10 or 15% application. Microhardness measurement was carried out on each enamel surface of the teeth for initial, after the demineralization and after application of the tooth pastes. It showed that there was significant decrease between enamel microhardness of the teeth at the initial condition and after demineralization. After application of the toothpaste containing green tea extract of each concentration the microhardnss increased significantly. However, there the microhardness was insignificant between the applications of each green tea concentration.

Green tea extract induces genes related to browning of white adipose tissue and limits weight-gain in high energy diet-fed rat.

PubMed

Chen, Li-Han; Chien, Yi-Wen; Liang, Chung-Tiang; Chan, Ching-Hung; Fan, Meng-Han; Huang, Hui-Yu

2017-01-01

Background: A wealth of research has reported on the anti-obesity effects of green tea extract (GTE). Although browning of white adipose tissue (WAT) has been reported to attenuate obesity, no study has disclosed the effects of GTE on browning in Sprague Dawley rats. Objectives: The aims of the study were to investigate the effects of GTE on anti-obesity and browning, and their underlying mechanisms. Methods: Four groups of rats (n=10/group) were used including a normal diet with vehicle treatment, and a high-energy diet (HED) with vehicle or GTE by oral gavage at 77.5 or 155 mg/kg/day for 8 weeks. Body weight, fat accumulation, and serum biochemical parameters were used to evaluate obesity. The gene expressions were analyzed using RT-qPCR and western blotting. Results: GTE modulated HED-induced body weight, fat accumulation, and serum levels of triacylglycerol, total cholesterol, low-density lipoprotein, free fatty acids, aspartate aminotransferase, and alanine aminotransferase. Moreover, GTE enhanced the serum high-density lipoprotein. Most importantly, the biomarkers of beige adipose tissue were up-regulated in WAT in GTE-given groups. GTE induced genes involved in different pathways of browning, and reduced transducin-like enhancer protein-3 in WAT. Conclusion: Our results suggest that GTE may improve obesity through inducing browning in HED-fed rats. Abbreviations : ALT: Alanine transaminase; AST: Aspartate transaminase; BAT: Brown adipose tissue; BMP-7: Bone morphogenetic protein-7; BW: Body weight; CIDEA: Cell death activator; CPT-1: Carnitine palmitoyltransferase-1; EFP: Epididymal fat pad; FFA: Free fatty acid; FGF-21: Fibroblast growth factor-21; GTE: Green tea extract; HDL: High-density lipoprotein; HED: high-energy diet; LDL: Low-density lipoprotein; MFP: Mesenteric fat pad; PGC-1α: Activates PPAR-γ coactivator-1; PPAR-γ: Peroxisome proliferator-activated receptor-γ; PRDM-16: PR domain containing 16; RFP: Renal fat pad; SD: Sprague Dawley; TC: Total

Myocardial potency of Bio-tea against Isoproterenol induced myocardial damage in rats.

PubMed

Lobo, Reema Orison; Shenoy, Chandrakala K

2015-07-01

Kombucha (Bio-tea) is a beverage produced by the fermentation of sugared black tea using a symbiotic association of bacteria and yeasts. Traditional claims about Kombucha report beneficial effects such as antibiotic properties, gastric regulation, relief from joint rheumatism and positive influence on the cholesterol level, arteriosclerosis, diabetes, and aging problems. The present investigation was carried out to understand the preventive effect of Kombucha on heart weight, blood glucose, total protein, lipid profile and cardiac markers in rats with myocardial damage induced using Isoproterenol. As Bio-tea is produced by fermenting tea, the parameters were compared in rats pre-treated with normal black tea and Bio-tea for 30 days followed by subcutaneous injection of Isoproterenol (85 mg/kg body weight). Normal rats as well as Isoproterenol induced myocardial infarcted rats were also used, which served as controls. Isoproterenol induced myocardial infarcted control rats showed a significant increase in heart weight, blood glucose and cardiac markers and a decrease in plasma protein. Increased levels of cholesterol, triglycerides, low density lipids (LDL) and very low density lipids (VLDL) were also observed, while the high density lipid (HDL) content decreased. Bio-tea showed a higher preventive effect against myocardial infarction when compared to tea, as was observed by the significant reduction in heart weight, and blood glucose and increase in plasma albumin levels. Bio-tea significantly decreased cholesterol, triglycerides, LDL and VLDL while simultaneously increasing the levels of HDL. Similarly a decrease in leakage of cardiac markers from the myocardium was also observed.

Hypotriacylglycerolemic and antiobesity properties of a new fermented tea product obtained by tea-rolling processing of third-crop green tea (Camellia sinensis) leaves and loquat (Eriobotrya japonica) leaves.

PubMed

Tanaka, Kazunari; Tamaru, Shizuka; Nishizono, Shoko; Miyata, Yuji; Tamaya, Kei; Matsui, Toshiro; Tanaka, Takashi; Echizen, Yoshie; Ikeda, Ikuo

2010-01-01

We manufactured a new fermented tea by tea-rolling processing of third-crop green tea (Camellia sinensis) leaves and loquat (Eriobotrya japonica) leaves. The mixed fermented tea extract inhibited pancreatic lipase activity in vitro, and effectively suppressed postprandial hypertriacylglycerolemia in rats. Rats fed a diet containing 1% freeze-dried fermented tea extract for 4 weeks had a significantly lower liver triacylglycerol concentration and white adipose tissue weight than those fed the control diet lacking fermented tea extract. The activity of fatty acid synthase in hepatic cytosol markedly decreased in the fermented tea extract group as compared to the control group. The serum and liver triacylglycerol- and body fat-lowering effects of the mixed fermented tea extract were strong relative to the level of dietary supplementation. These results suggest that the new fermented tea product exhibited hypotriacylglycerolemic and antiobesity properties through suppression of both liver fatty acid synthesis and postprandial hypertriacylglycerolemia by inhibition of pancreatic lipase.

Therapeutic effect of Northern Labrador tea extracts for acute myeloid leukemia.

PubMed

McGill, Colin M; Tomco, Patrick L; Ondrasik, Regina M; Belknap, Kaitlyn C; Dwyer, Gaelen K; Quinlan, Daniel J; Kircher, Thomas A; Andam, Cheryl P; Brown, Timothy J; Claxton, David F; Barth, Brian M

2018-04-27

Acute myeloid leukemia (AML) is an aggressive hematological malignancy that is one of the more common pediatric malignancies in addition to occurring with high incidence in the aging population. Unfortunately, these patient groups are quite sensitive to toxicity from chemotherapy. Northern Labrador tea, or Rhododendron tomentosum Harmaja (a.k.a. Ledum palustre subsp. decumbens) or "tundra tea," is a noteworthy medicinal plant used by indigenous peoples in Alaska, Canada, and Greenland to treat a diversity of ailments. However, laboratory investigations of Northern Labrador tea, and other Labrador tea family members, as botanical sources for anticancer compounds have been limited. Utilizing an AML cell line in both in vitro and in vivo studies, as well as in vitro studies using primary human AML patient samples, this study demonstrated for the first time that Northern Labrador tea extracts can exert anti-AML activity and that this may be attributed to ursolic acid as a constituent component. Therefore, this medicinal herb holds the potential to serve as a source for further drug discovery efforts to isolate novel anti-AML compounds. Copyright © 2018 John Wiley & Sons, Ltd.

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice

PubMed Central

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil

2014-01-01

BACKGROUND/OBJECTIVES Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. MATERIALS/METHODS Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). RESULTS The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. CONCLUSIONS Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression. PMID:25110559

Protective effect of the standardized green tea seed extract on UVB-induced skin photoaging in hairless mice.

PubMed

Lim, Jae-Youn; Kim, Ok-Kyung; Lee, Jeongmin; Lee, Min-Jae; Kang, Namgil; Hwang, Jae-Kwan

2014-08-01

Ultraviolet B (UVB) irradiation on skin can induce production of reactive oxygen species (ROS), which cause expression of matrix metalloproteinases (MMPs) and collagen degradation. Thus, chronic exposure of skin to UVB irradiation leads to histological changes consistent with aging, such as wrinkling, abnormal pigmentation, and loss of elasticity. We investigated the protective effect of the standardized green tea seed extract (GSE) on UVB-induced skin photoaging in hairless mice. Skin photoaging was induced by UVB irradiation on the back of Skh-1 hairless mice three times per week and UVB irradiation was performed for 10 weeks. Mice were divided into six groups; normal control, UVB irradiated control group, positive control (UVB + dietary supplement of vitamin C 100 mg/kg), GSE 10 mg/kg (UVB + dietary supplement of GSE 10 mg/kg), GSE 100 mg/kg (UVB + dietary supplement of GSE 100 mg/kg), and GSE 200 mg/kg (UVB + dietary supplement of GSE 200 mg/kg). The dietary supplement GSE attenuated UVB irradiation-induced wrinkle formation and the decrease in density of dermal collagen fiber. In addition, results of the antioxidant analysis showed that GSE induced a significant increase in antioxidant enzyme activity compared with the UVB irradiation control group. Dietary supplementation with GSE 200 mg/kg resulted in a significant decrease in expression of MMP-1, MMP-3, and MMP-9 and an increase in expression of TIMP and type-1 collagen. Findings of this study suggest that dietary supplement GSE could be useful in attenuation of UVB irradiation-induced skin photoaging and wrinkle formation due to regulation of antioxidant defense systems and MMPs expression.

Assessment of the polyphenolic composition of the organic extracts of Mauritian black teas: a potential contributor to their antioxidant functions.

PubMed

Luximon-Ramma, Amitabye; Neergheen, Vidushi S; Bahorun, Theeshan; Crozier, Alan; Zbarsky, Virginia; Datla, Krishna P; Dexter, David T; Aruoma, Okezie I

2006-01-01

There is increasing interest in the emerging view that tea improves the antioxidant status in vivo and thereby helps to lower risk of certain types of cancer, coronary heart disease and stroke and its component biofactors could provide prophylactic potential for these diseases. The polyphenolic composition and the antioxidant properties of organic extracts (acetone/methanol) of Mauritian commercial black teas were evaluated. HPLC data of the individual compounds revealed remarkably high levels (+)-Catechin ((+)-C), (-)-epicatechin ((-)-EC), (-)-epicatechin 3-gallate ((-)-ECG), (-)-epigallocatechin ((-)-EGC), (-)-epigallocatechin 3-gallate ((-)-EGCG) and gallic acid. Analysis of hydrolysed extracts indicated that quercetin was the dominant flavonol aglycone with traces of myricetin and kaempferol. Based on the Ferric Reducing Antioxidant Power (FRAP) and the Trolox Equivalent Antioxidant Capacity (TEAC) assays Extra tea from Bois Chéri exhibited the highest antioxidant potential. Linear regression analyses showed that the antioxidant capacities of the organic extracts are strongly influenced by total phenols (TEAC: r=0.95 and FRAP: r=0.96) and to a lesser extent by total proanthocyanidin and total flavonoid contents. Catechins and gallic acid seem to add up to the overall antioxidant capacity of black tea extracts. The fresh tea leaves had high levels of total phenols, total flavonoids, total proanthocyanidin and exhibited greater antioxidant potential when compared with black teas. Organic extracts of endemic teas represent useful source of phenolic antioxidants supplements for prophylactic use.

Antioxidant-mediated preventative effect of Dragon-pearl tea crude polyphenol extract on reserpine-induced gastric ulcers.

PubMed

Yi, Ruokun; Wang, Rui; Sun, Peng; Zhao, Xin

2015-07-01

Dragon-pearl tea is a type of green tea commonly consumed in Southwest China. In the present study, the antioxidative and anti-gastric ulcer effects of Dragon-pearl tea crude polyphenols (DTCP) were determined in vitro and in vivo . Treatment with 25, 50 or 100 µg/ml DTCP resulted in notable antioxidant effects in vitro , which manifested as 2,2-diphenyl-1-picrylhydrazyl and OH radical-scavenging activity. Furthermore, using an in vivo mouse model, DTCP was shown to reduce the gastric ulcer area in the stomach, in which the 200 mg/kg DTCP dose exhibited the most marked effect, with a gastric ulcer index inhibitory rate of 72.63%. In addition, DTCP was demonstrated to improve stomach acidity conditions in vivo by increasing the pH and reducing the level of gastric juice, as compared with the reserpine-induced gastric ulcer control mice. Furthermore, DTCP altered the serum levels of a number of oxidation-related biomolecules, including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), malondialdehyde (MDA), lipid peroxidation (LPO) and catalase (CAT), to subsequently exert an anti-gastric ulcer effect. Treatment with 50, 100 and 200 mg/kg DTCP increased the SOD, GSH-Px and CAT levels and reduced the MDA and LPO levels in the mouse model of gastric ulcers. These serum level alterations resulted in the modified serum levels of prostaglandin E2 (PGE2) and nitric oxide (NO), which are associated with gastric mucosal protection. A reverse transcription-quantitative polymerase chain reaction (RT-PCR) assay is a molecular biology experiment which could determine the changes of mRNA in tissues. Using the RT-PCR assay, DTCP was observed to increase the mRNA expression levels of certain genes associated with gastric ulcers: Epidermal growth factor, epidermal growth factor receptor, vascular endothelial growth factor and vascular endothelial growth factor receptor 1, while reducing gastrin expression levels. Therefore, the results indicated that DTCP induced a

A modified extraction and clean-up procedure for the detection and determination of parathion-methyl and chlorpyrifos residues in tea.

PubMed

Shanker, A; Sood, C; Kumar, V; Ravindranath, S D

2001-05-01

Recent advances in methodology and instrumentation have made possible the detection and determination of pesticides at microgram kg-1 (ppb) levels. The sensitivity of a method of analysis depends greatly on the efficient extraction of the pesticide and the subsequent clean-up of the extract. The extract from green tea leaves is a mixture of aroma components, polyphenols and caffeine. The preparation of made tea from green tea leaves adds to this complexity by concentrating these coextractives. Conventional clean-up techniques provide poor recoveries for parathion-methyl and chlorpyrifos from both green tea leaves and made tea. This arises from interference by caffeine during gas chromatography, as it has a similar retention time to the two pesticides and peaks overlap. A modification to the protocol based on a solvent partitioning process using dichloromethane and subsequent washing of the extracts with warm water removed the caffeine, and pigments were removed by column chromatography. Recoveries ranging from 80 to 90% were then obtained for both pesticides.

Conventional and Accelerated-Solvent Extractions of Green Tea (Camellia sinensis) for Metabolomics-based Chemometrics

PubMed Central

Kellogg, Joshua J.; Wallace, Emily D.; Graf, Tyler N.; Oberlies, Nicholas H.; Cech, Nadja B.

2018-01-01

Metabolomics has emerged as an important analytical technique for multiple applications. The value of information obtained from metabolomics analysis depends on the degree to which the entire metabolome is present and the reliability of sample treatment to ensure reproducibility across the study. The purpose of this study was to compare methods of preparing complex botanical extract samples prior to metabolomics profiling. Two extraction methodologies, accelerated solvent extraction and a conventional solvent maceration, were compared using commercial green tea [Camellia sinensis (L.) Kuntze (Theaceae)] products as a test case. The accelerated solvent protocol was first evaluated to ascertain critical factors influencing extraction using a D-optimal experimental design study. The accelerated solvent and conventional extraction methods yielded similar metabolite profiles for the green tea samples studied. The accelerated solvent extraction yielded higher total amounts of extracted catechins, was more reproducible, and required less active bench time to prepare the samples. This study demonstrates the effectiveness of accelerated solvent as an efficient methodology for metabolomics studies. PMID:28787673

Protective effects of Ziyang tea polysaccharides on CCl4-induced oxidative liver damage in mice.

PubMed

Wang, Dongying; Zhao, Yan; Sun, Yanfei; Yang, Xingbin

2014-01-15

This study was designed to investigate the hepatoprotective effects of the tea polysaccharides (ZTPs) extracted from a selenium-enriched Ziyang green tea (Camellia sinensis). ZTPs were identified as the heteropolysaccharides with glucose (31.4%), arabinose (23.5%) and galactose (21.8%) being the main constitutive monosaccharides. ZTPs displayed noteworthy scavenging effects against DPPH, OH and O2(-), and high antioxidant effects in vitro, and the effects were further verified by suppressing CCl4-induced oxidative liver damage in mice at 100, 200 and 400mg/kg BW. Administration of ZTPs in mice prior to CCl4 significantly prevented the CCl4-induced increases in serum alanine aminotransferase, aspartate aminotransferase and lactic dehydrogenase, as well as hepatic malondialdehyde level. Mice treated with ZTPs showed normal glutathione peroxidase and superoxide dismutase activities, relative to CCl4-treated group. ZTPs also prevented the CCl4-caused liver histological alteration, as indicated by histopathological evaluation. These findings demonstrate that ZTPs have protective effects against acute CCl4-induced oxidative liver damage. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of Catechins, Green tea Extract and Methylxanthines in Combination with Gentamicin Against Staphylococcus aureus and Pseudomonas aeruginosa

PubMed Central

Fazly Bazzaz, Bibi Sedigheh; Sarabandi, Sahar; Khameneh, Bahman; Hosseinzadeh, Hossein

2016-01-01

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. Therefore

Separation of major catechins from green tea by ultrahigh pressure extraction.

PubMed

Jun, Xi; Shuo, Zhao; Bingbing, Lu; Rui, Zhang; Ye, Li; Deji, Shen; Guofeng, Zhou

2010-02-15

This study presents a novel extraction technique, ultrahigh pressure extraction, to obtain major catechins from green tea leaves. The effects of various high pressure level (100, 200, 300, 400, 500, 600 MPa) on the extract are examined. HPLC chromatographic analyses determine the concentration of four major catechins and caffeine. The extraction yields of active ingredients with ultrahigh pressure extraction (400 MPa pressure) for only 15 min were given the same as those of organic solvent extraction for 2h. These excellent results for the ultrahigh pressure extraction are promising for the future separation of active ingredients from traditional Chinese herbal medicine. Copyright 2009 Elsevier B.V. All rights reserved.

Influence of the extraction method on the yield of flavonoids and phenolics from Sideritis spp. (Pirin Mountain tea).

PubMed

Alipieva, Kalina; Petreska, Jasmina; Gil-Izquierdo, Angel; Stefova, Marina; Evstatieva, Ljuba; Bankova, Vassya

2010-01-01

The influence of the extraction method on the yield and composition of extracts of Sideritis (Pirin mountain tea) has been studied. Maceration, ultrasound-assisted (USAE) and microwave assisted extraction (MAE) were applied. Total phenolics and total flavonoids were quantified spectrophotometrically, and individual compounds were analyzed by HPLC-DAD-MS(n). This preliminary study reveals that the traditional way of tea preparation from Sideritis is the most appropriate in order to extract the maximum of total flavonoids and total phenolics. In the case of methanol extraction, the optimal method is USAE.

Effects of Green Tea Extract on Learning, Memory, Behavior and Acetylcholinesterase Activity in Young and Old Male Rats

ERIC Educational Resources Information Center

Kaur, Tranum; Pathak, C. M.; Pandhi, P.; Khanduja, K. L.

2008-01-01

Objective: To study the effects of green tea extract administration on age-related cognition in young and old male Wistar rats. Methods: Young and old rats were orally administered 0.5% green tea extract for a period of eight weeks and were evaluated by passive avoidance, elevated maze plus paradigm and changes in acetylcholinesterase activity.…

Conventional and accelerated-solvent extractions of green tea (camellia sinensis) for metabolomics-based chemometrics.

PubMed

Kellogg, Joshua J; Wallace, Emily D; Graf, Tyler N; Oberlies, Nicholas H; Cech, Nadja B

2017-10-25

Metabolomics has emerged as an important analytical technique for multiple applications. The value of information obtained from metabolomics analysis depends on the degree to which the entire metabolome is present and the reliability of sample treatment to ensure reproducibility across the study. The purpose of this study was to compare methods of preparing complex botanical extract samples prior to metabolomics profiling. Two extraction methodologies, accelerated solvent extraction and a conventional solvent maceration, were compared using commercial green tea [Camellia sinensis (L.) Kuntze (Theaceae)] products as a test case. The accelerated solvent protocol was first evaluated to ascertain critical factors influencing extraction using a D-optimal experimental design study. The accelerated solvent and conventional extraction methods yielded similar metabolite profiles for the green tea samples studied. The accelerated solvent extraction yielded higher total amounts of extracted catechins, was more reproducible, and required less active bench time to prepare the samples. This study demonstrates the effectiveness of accelerated solvent as an efficient methodology for metabolomics studies. Copyright © 2017. Published by Elsevier B.V.

Green tea extracts ameliorate high-fat diet-induced muscle atrophy in senescence-accelerated mouse prone-8 mice.

PubMed

Onishi, Shintaro; Ishino, Mayu; Kitazawa, Hidefumi; Yoto, Ai; Shimba, Yuki; Mochizuki, Yusuke; Unno, Keiko; Meguro, Shinichi; Tokimitsu, Ichiro; Miura, Shinji

2018-01-01

Muscle atrophy (loss of skeletal muscle mass) causes progressive deterioration of skeletal function. Recently, excessive intake of fats was suggested to induce insulin resistance, followed by muscle atrophy. Green tea extracts (GTEs), which contain polyphenols such as epigallocatechin gallate, have beneficial effects on obesity, hyperglycemia, and insulin resistance, but their effects against muscle atrophy are still unclear. Here, we found that GTEs prevented high-fat (HF) diet-induced muscle weight loss in senescence-accelerated mouse prone-8 (SAMP8), a murine model of senescence. SAMP8 mice were fed a control diet, an HF diet, or HF with 0.5% GTEs (HFGT) diet for 4 months. The HF diet induced muscle weight loss with aging (measured as quadriceps muscle weight), whereas GTEs prevented this loss. In HF diet-fed mice, blood glucose and plasma insulin concentrations increased in comparison with the control group, and these mice had insulin resistance as determined by homeostasis model assessment of insulin resistance (HOMA-IR). In these mice, serum concentrations of leukocyte cell-derived chemotaxin 2 (LECT2), which is known to induce insulin resistance in skeletal muscle, were elevated, and insulin signaling in muscle, as determined by the phosphorylation levels of Akt and p70 S6 kinases, tended to be decreased. In HFGT diet-fed mice, these signs of insulin resistance and elevation of serum LECT2 were not observed. Although our study did not directly show the effect of serum LECT2 on muscle weight, insulin resistance examined using HOMA-IR indicated an intervention effect of serum LECT2 on muscle weight, as revealed by partial correlation analysis. Accordingly, GTEs might have beneficial effects on age-related and HF diet-induced muscle weight loss, which correlates with insulin resistance and is accompanied by a change in serum LECT2.

Antioxidant potential of tea reduces arsenite induced oxidative stress in Swiss albino mice.

PubMed

Sinha, D; Roy, S; Roy, M

2010-04-01

Environmental arsenic (As) is a potent human carcinogen and groundwater As contamination is a major health concern in West Bengal, India. Oxidative stress has been one of the prime factors in As-induced carcinogenicity. Generation of reactive oxygen species (ROS), beyond the body's endogenous antioxidant balance cause a severe imbalance of the cellular antioxidant defence mechanism. Tea, a popular beverage has excellent chemopreventive and antioxidant properties. In this study it was investigated whether these flavonoids could ameliorate the arsenite (As III) induced oxidative stress in Swiss albino mice. Bio-monitoring with comet assay elicited that the increase in genotoxicity caused by As III was counteracted by both black tea and green tea. Elevated levels of lipid peroxides and protein carbonyl by As III were effectively reduced with green as well as black tea. They also exhibited protective action against the As III induced depletion of antioxidants like catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), glutathione-S-transferase (GST) and glutathione (GSH) in mice liver tissue. Thus the tea polyphenols by virtue of their antioxidant potential may be used as an effective agent to reduce the As III induced oxidative stress in Swiss albino mice. 2010 Elsevier Ltd. All rights reserved.

Efficacy of methanolic extract of green and black teas against extended-spectrum β-Lactamase-producing Pseudomonas aeruginosa.

PubMed

Taherpour, Arezou; Hashemi, Ali; Erfanimanesh, Soroor; Taki, Elahe

2016-07-01

Pseudomonas aeruginosa is one of the major bacteria causing acute infections. β-Lactamase production is the principal defense mechanism in gram-negative bacteria. The aim of our study was to evaluate the antibacterial activity of Methanolic Extracts of Green and Black Teas on P. aeruginosa Extended Spectrum-β-Lactamases (ESBLs) production. This research was carried out on burn wounds of 245 hospitalized patients in Kerman, Iran. P. aeruginosa ESBLs and MBL producing strains were detected by Combination Disk Diffusion Test (CDDT) and Epsilometer test (E-test) strips, respectively. Minimum inhibitory concentration (MIC) was measured for Ceftazidime, Meropenem, Imipenem, Aztreonam, Cefotaxime and methanollic extracts of Camellia Sinensis (Green Tea). From 245 patients in the burn ward, 120 cases were infected with P. aeruginosa. 41 isolates contained ESBL while MBL was not detected. P. aeruginosa were resistant to Cefotaxime, Aztreonam, Ceftazidime, Meropenem and Imipenem, 72 (60%), 50 (41.66%), 79 (65.83%), 33 (27.5%) and 24 (20%), respectively. Green tea extract had the highest anti-bacterial effect on standard and P. aeruginosa strains in 1.25mg/ml concentration. This study determined that the methanolic extract of green tea has a higher effect against ESBL producing P. aeruginosa than Cefotaxime, Aztreonam and Ceftazidime.

Green tea extract for periodontal health

PubMed Central

Venkateswara, Babu; Sirisha, K.; Chava, Vijay K.

2011-01-01

Tea, the commonly consumed beverage, is gaining increased attention in promoting overall health. In specific, green tea is considered a healthful beverage due to the biological activity of its polyphenols namely catechins. Among the polyphenols Epigallo catechin 3 gallate and Epicatechin 3 Gallate are the most predominant catechins. The antioxidant, antimicrobial, anticollagenase, antimutagenic, and c hemopreventive properties of these catechins proved to be helpful in the treatment of chronic diseases like periodontal disease. Studies have demonstrated that the type of processing mainly effects the concentration of catechins. Several epidemiological studies have proved that green tea also has some general health benefitting properties like antihypertensive, reduction of cardiovascular risk, antibacterial, antiviral, and antifungal activity. The present review concentrates on the effects of green tea in periodontal and general health. PMID:21772716

Mangiferin Has an Additive Effect on the Apoptotic Properties of Hesperidin in Cyclopia sp. Tea Extracts

PubMed Central

Bartoszewski, Rafal; Hering, Anna; Marszałł, Marcin; Stefanowicz Hajduk, Justyna; Bartoszewska, Sylwia; Kapoor, Niren; Kochan, Kinga; Ochocka, Renata

2014-01-01

A variety of biological pro-health activities have been reported for mangiferin and hesperidin, two major phenolic compounds of Honeybush (Cyclopia sp.) tea extracts. Given their increasing popularity, there is a need for understanding the mechanisms underlying the biological effects of these compounds. In this study, we used real-time cytotoxicity cellular analysis of the Cyclopia sp. extracts on HeLa cells and found that the higher hesperidin content in non-fermented "green" extracts correlated with their higher cytotoxicity compared to the fermented extracts. We also found that mangiferin had a modulatory effect on the apoptotic effects of hesperidin. Quantitative PCR analysis of hesperidin-induced changes in apoptotic gene expression profile indicated that two death receptor pathway members, TRADD and TRAMP, were up regulated. The results of this study suggest that hesperidin mediates apoptosis in HeLa cells through extrinsic pathway for programmed cell death. PMID:24633329

Optimisation of supercritical carbon dioxide extraction of essential oil of flowers of tea (Camellia sinensis L.) plants and its antioxidative activity.

PubMed

Chen, Zhenchun; Mei, Xin; Jin, Yuxia; Kim, Eun-Hye; Yang, Ziyin; Tu, Youying

2014-01-30

To extract natural volatile compounds from tea (Camellia sinensis) flowers without thermal degradation and residue of organic solvents, supercritical fluid extraction (SFE) using carbon dioxide was employed to prepare essential oil of tea flowers in the present study. Four important parameters--pressure, temperature, static extraction time, and dynamic extraction time--were selected as independent variables in the SFE. The optimum extraction conditions were the pressure of 30 MPa, temperature of 50°C, static time of 10 min, and dynamic time of 90 min. Based on gas chromatography-mass spectrometry analysis, 59 compounds, including alkanes (45.4%), esters (10.5%), ketones (7.1%), aldehydes (3.7%), terpenes (3.7%), acids (2.1%), alcohols (1.6%), ethers (1.3%) and others (10.3%) were identified in the essential oil of tea flowers. Moreover, the essential oil of tea flowers showed relatively stronger DPPH radical scavenging activity than essential oils of geranium and peppermint, although its antioxidative activity was weaker than those of essential oil of clove, ascorbic acid, tert-butylhydroquinone, and butylated hydroxyanisole. Essential oil of tea flowers using SFE contained many types of volatile compounds and showed considerable DPPH scavenging activity. The information will contribute to the future application of tea flowers as raw materials in health-care food and food flavour industries. © 2013 Society of Chemical Industry.

Green tea polyphenols avert chronic inflammation-induced myocardial fibrosis of female rats

USDA-ARS?s Scientific Manuscript database

Objective: Green tea proposes anti-inflammatory properties which may attenuate chronic inflammation-induced fibrosis of vessels. This study evaluated whether green tea polyphenols (GTP) can avert fibrosis or vascular disruption along with mechanisms in rats with chronic inflammation. Treatments: Fo...

Physiological effects of formulation containing tannase-converted green tea extract on skin care: physical stability, collagenase, elastase, and tyrosinase activities.

PubMed

Hong, Yang-Hee; Jung, Eun Young; Noh, Dong Ouk; Suh, Hyung Joo

2014-03-01

Green tea contains numerous polyphenols, which have health-promoting effects. The purpose of this study was to evaluate the effect of tannase-converted green tea extract (TGE) formulation on the physical stability and activities of skin-related enzymes. Physical stability was evaluated by measuring the pH, precipitation, and colors at 25 ± 2 °C/ambient humidity and at 40 ± 2 °C/70% ± 5% relative humidity for 4 months. Activities of collagenase, elastase, and tyrosinase as skin-related enzymes were assessed on TGE formulation. The concentrations of epigallocatechin-3-gallate and epicatechin-3-gallate in green tea extract were greatly decreased to the extent of negligible level when treated with tannase. The formulation containing 5% tannase-converted green tea extract showed relatively stable pH, precipitation, and color features for 16 weeks. When TGE was added to the formulation, there was a significant increase in the inhibition of elastase and tyrosinase activities ( p  < 0.05) compared with the formulation containing 5% normal green tea extract. The TGE could be used in cosmetics as skin antiwrinkling or depigmenting agent.

Using tea stalk lignocellulose as an adsorbent for separating decaffeinated tea catechins.

PubMed

Ye, J H; Jin, J; Liang, H L; Lu, J L; Du, Y Y; Zheng, X Q; Liang, Y R

2009-01-01

Lignocelluloses prepared from woody tea stalk, pine sawdust and sugarcane bagasse were used as adsorbents to isolate decaffeinated catechins from tea extracts and compared with synthetic macroporous resin HPD 600. HPD 600 had the highest adsorption capacity to catechins, followed by tea stalk lignocellulose while lignocelluloses of pine sawdust and bagasse the least. Tea stalk lignocellulose absorbed preferentially tea catechins and showed a good selectivity. HPD 600 absorbed caffeine and tea catechins simultaneously. The kinetics data of tea stalk lignocellulose showed a good fit with the Langmuir isotherm model. It is considered that tea stalk lignocellulose is an alternative low-cost adsorbent for preparing decaffeinated tea catechins.

Grape seed and tea extracts and catechin 3-gallates are potent inhibitors of α-amylase and α-glucosidase activity.

PubMed

Yilmazer-Musa, Meltem; Griffith, Anneke M; Michels, Alexander J; Schneider, Erik; Frei, Balz

2012-09-12

This study evaluated the inhibitory effects of plant-based extracts (grape seed, green tea, and white tea) and their constituent flavan-3-ol monomers (catechins) on α-amylase and α-glucosidase activity, two key glucosidases required for starch digestion in humans. To evaluate the relative potency of extracts and catechins, their concentrations required for 50 and 90% inhibition of enzyme activity were determined and compared to the widely used pharmacological glucosidase inhibitor, acarbose. Maximum enzyme inhibition was used to assess relative inhibitory efficacy. Results showed that grape seed extract strongly inhibited both α-amylase and α-glucosidase activity, with equal and much higher potency, respectively, than acarbose. Whereas tea extracts and catechin 3-gallates were less effective inhibitors of α-amylase, they were potent inhibitors of α-glucosidase. Nongallated catechins were ineffective. The data show that plant extracts containing catechin 3-gallates, in particular epigallocatechin gallate, are potent inhibitors of α-glucosidase activity and suggest that procyanidins in grape seed extract strongly inhibit α-amylase activity.

Protective effect of kombucha mushroom (KM) tea on phenol-induced cytotoxicity in albino mice.

PubMed

Yapar, Kursad; Cavusoglu, Kultigin; Oruc, Ertan; Yalcin, Emine

2010-09-01

The present study was carried out to evaluate the protective role of kombucha mushroom (KM) tea on cytotoxicity induced by phenol (PHE) in mice. We used weight gain and micronucleus (MN) frequency as indicators of cytotoxicity and supported these parameters with pathological findings. The animals were randomly divided into seven groups: (Group I) only tap water (Group II) 1000 microl kg(-1) b. wt KM-tea, (Group III) 35 mg kg(-1) body wt. PHE (Group IV) 35 mg kg(-1) body wt. PHE + 250 microl kg(-1) b. wt KM-tea (Group V) 35 mg kg(-1) b. wt PHE + 500 microl kg(-1) b. wt KM-tea (Group VI) 35 mg kg(-1) b. wt PHE + 750 microl kg(-1) b. wt KM-tea, (Group VII) 35 mg kg(-1) b. wt PHE + 1000 microl kg(-1) b. wt KM-tea, for 20 consecutive days by oral gavage. The results indicated that all KM-tea supplemented mice showed a lower MN frequency than erythrocytes in only PHE-treated group. There was an observable regression on account of lesions in tissues of mice supplemented with different doses of KM-tea in histopathological observations. In conclusion, the KM-tea supplementation decreases cytotoxicity induced by PHE and its protective role is dose-dependent.

The analysis of aroma/flavor compounds in green tea using ice concentration linked with extractive stirrer.

PubMed

Alluhayb, Abdullah H; Logue, Brian A

2017-10-06

Worldwide, green tea is one of the most popular beverages. It promotes blood circulation, liver function, and lowers the risk of cancer and cardiovascular diseases. This drink is characterized by the distinctive odors and flavors produced by its constituent compounds, with its value predicated on the amount and type of constituents extracted from the tea leaves during brewing. Ice concentration linked with extractive stirrer (ICECLES) is a novel sample preparation technique, especially applicable for the extraction of relatively polar compounds while retaining excellent extraction efficiencies for non-polar compounds. In this study, ICECLES was used to prepare green tea for analysis of aroma/flavor compounds by gas chromatography-mass spectrometry (GC-MS). ICECLES performed very well, revealing 301 constituents as compared to 245 for SBSE (i.e., 56 more constituents were detected via ICECLES). Moreover, ICECLES produced stronger signal to noise ratios for all except 4 of 301 constituents, with a maximum signal enhancement of 19. Of the constituents which were only detectable using ICECLES, some very important aroma/flavor and/or medicinal compounds were easily identified, including furfural, furfural alcohol, maltol, eugenol, 2-methylpyrazine, phenethyl alcohol, 2,6-dimethoxyphenol, and α-terpineol. Overall, we confirmed that ICECLES sample preparation followed by GC-MS consistently allowed more complete green tea aroma/flavor analysis, especially for relatively polar compounds, some of which are critical for flavor quality. Copyright © 2017 Elsevier B.V. All rights reserved.

Interaction of green tea polyphenols with dairy matrices in a simulated gastrointestinal environment.

PubMed

Lamothe, Sophie; Azimy, Naheed; Bazinet, Laurent; Couillard, Charles; Britten, Michel

2014-10-01

The consumption of polyphenols in green tea has been associated with beneficial health effects. Although polyphenols are unstable in the intestinal environment, they may be protected by interactions with dairy proteins during digestion. The objectives of this study were to evaluate the effect of a green tea extract on the digestibility of different dairy matrices and to monitor the antioxidant activity of these matrices with or without the green tea extract during digestion in a simulated gastrointestinal environment. Milk, yogurt and cheese with similar fat-to-protein ratios were subjected to simulated digestion. Matrix degradation, protein and fat hydrolysis, polyphenol concentration and radical scavenging activity were analyzed during gastric and intestinal digestion phases. Cheese was the matrix most resistant to protein and fat digestion. The addition of the green tea extract significantly decreased proteolysis in the gastric phase but had no effect in the intestinal phase. The kinetics of fatty acid release was reduced by the presence of the green tea extract. Transition from the gastric phase to the intestinal phase induced a 50% decrease in the antioxidant activity of the control (tea extract dispersed in water) due to the degradation of polyphenols. The presence of dairy matrices significantly improved polyphenol stability in the intestinal phase and increased the antioxidant activity by 29% (cheese) to 42% (milk) compared to the control. These results suggest that simultaneous consumption of green tea and dairy products helps to maintain the integrity and antioxidant activity of polyphenols during digestion.

Investigation of Polyhenolic Content of Rose Hip (Rosa canina L.) Tea Extracts: A Comparative Study

PubMed Central

İlbay, Zeynep; Şahin, Selin; Kırbaşlar, Ş. İsmail

2013-01-01

Three different brands of Rose hip (Rosa canina L.) tea were extracted with water, ethanol (EtOH), methanol (MeOH), and aqueous mixtures (50%, v/v) by ultrasound-assisted extraction (UAE) and Soxhlet methods. Total phenolic content was determined according to the Folin-Ciocalteu method. The results were presented by means of the extract yields and total phenolic contents, expressed in gallic acid equivalent (GAE) per g of dried matter (DM). The greatest amount of extract observed in tea samples was obtained by UAE through water with the value of 619.37 ± 0.58 mg/g DM. Regarding the phenolic content, the best result was achieved by the Soxhlet method through 50% MeOH mixture (59.69 ± 0.89 mg GAE/g DM), followed by the UAE method with water (48.59 ± 0.29 mg GAE/g DM). PMID:28239095

Determination of the inhibitory effect of green tea extract on glucose-6-phosphate dehydrogenase based on multilayer capillary enzyme microreactor.

PubMed

Camara, Mohamed Amara; Tian, Miaomiao; Liu, Xiaoxia; Liu, Xin; Wang, Yujia; Yang, Jiqing; Yang, Li

2016-08-01

Natural herbal medicines are an important source of enzyme inhibitors for the discovery of new drugs. A number of natural extracts such as green tea have been used in prevention and treatment of diseases due to their low-cost, low toxicity and good performance. The present study reports an online assay of the activity and inhibition of the green tea extract of the Glucose 6-phosphate dehydrogenase (G6PDH) enzyme using multilayer capillary electrophoresis based immobilized enzyme microreactors (CE-IMERs). The multilayer CE-IMERs were produced with layer-by-layer electrostatic assembly, which can easily enhance the enzyme loading capacity of the microreactor. The activity of the G6PDH enzyme was determined and the enzyme inhibition by the inhibitors from green tea extract was investigated using online assay of the multilayer CE-IMERs. The Michaelis constant (Km ) of the enzyme, the IC50 and Ki values of the inhibitors were achieved and found to agree with those obtained using offline assays. The results show a competitive inhibition of green tea extract on the G6PDH enzyme. The present study provides an efficient and easy-to-operate approach for determining G6PDH enzyme reaction and the inhibition of green tea extract, which may be beneficial in research and the development of natural herbal medicines. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Protective effects of green tea on olanzapine-induced-metabolic syndrome in rats.

PubMed

Razavi, Bibi Marjan; Lookian, Fariba; Hosseinzadeh, Hossein

2017-08-01

Atypical antipsychotics particularly olanzapine are associated with obesity and serious metabolic disturbances. As green tea (Camellia sinensis) is generally associated with beneficial effects on obesity and other metabolic disturbances, this study was undertaken to evaluate the effect of green tea aqueous extract (GTAE) on olanzapine induced weight gain and metabolic abnormalities in rats. Male Wistar rats were divided into eight groups: control, olanzapine (5mg/kg/day, IP.), GTAE (25, 50 and 100mg/kg/day, IP.) plus olanzapine and GTAE (25, 50 and 100mg/kg/day, IP.). Treatments were continued for 11 days. Body weight gain, average food and water intake were measured during the experiment. Plasma lipid, glucose and leptin levels, mean systolic blood pressure and total locomotion were evaluated at the end of experiment. Olanzapine induced significant weight gain at the end of treatment (10.38% of body weight) when compared to control (3.13% of body weight) in male Wistar rats. Average food and water intake were increased by olanzapine treatment. 11days olanzapine administration led to hyperleptinemia, hyperglycemia and dyslipidemia. Olanzapine also increased mean systolic blood pressure and decreased total locomotion. GTAE decreased significantly body weight gain and average food and water intake, improved the changes in lipid profile as well as fasting blood glucose, and finally decreased hyperleptinemia and hypertension induced by olanzapine. Results of this study demonstrated that GTAE could exert protective effects against olanzapine induced obesity partially due to its lowering effect on leptin. GTAE improved other metabolic abnormalities including dyslipidemia, hyperglycemia and hypertension induced by olanzapine in rats. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Cymbopogon citratus and Camellia sinensis extracts selectively induce apoptosis in cancer cells and reduce growth of lymphoma xenografts in vivo

PubMed Central

Philion, Cory; Ma, Dennis; Ruvinov, Ivan; Mansour, Fadi; Pignanelli, Christopher; Noel, Megan; Saleem, Ammar; Arnason, John; Rodrigues, Mark; Singh, Inderpal; Ropat, Jesse; Pandey, Siyaram

2017-01-01

Cancer cells are reported to have elevated levels of reactive oxygen species (ROS) and are highly dependent on cellular defense mechanisms against oxidative stress. Numerous nutraceuticals and natural polyphenolic compounds have a wide range of abilities to alter cellular redox states with potential implications in various diseases. Furthermore, therapeutic options for cancers are mostly nonselective treatments including genotoxic or tubulin-targeting compounds. Some of the natural extracts, containing multiple bioactive compounds, could target multiple pathways in cancer cells to selectively induce cell death. Cymbopogon citratus (lemongrass) and Camellia sinensis (white tea) extracts have been shown to have medicinal properties, however, their activity against lymphoma and leukemia, as well as mechanistic details, have not been fully characterized. Herein, we report potent anti-cancer properties in dose and time-dependent manners of ethanolic lemongrass and hot water white tea extracts in lymphoma and leukemia models. Both extracts were able to effectively induce apoptosis selectively in these human cancer cell types. Interestingly, ethanolic lemongrass extract induces apoptosis primarily by the extrinsic pathway and was found to be dependent on the generation of ROS. Conversely, apoptotic induction by hot water white tea extract was independent of ROS. Furthermore, both of these extracts caused mitochondrial depolarization and decreased rates of oxygen consumption in lymphoma and leukemia cells, leading to cell death. Most importantly, both these extracts were effective in reducing tumor growth in human lymphoma xenograft models when administered orally. Thus, these natural extracts could have potential for being nontoxic alternatives for the treatment of cancer. PMID:29340014

Effects of tea or tea extract on metabolic profiles in patients with type 2 diabetes mellitus: a meta-analysis of ten randomized controlled trials.

PubMed

Li, Yanchuan; Wang, Cheng; Huai, Qingjie; Guo, Fuchuan; Liu, Liyan; Feng, Rennan; Sun, Changhao

2016-01-01

As consumption of tea has been confirmed as a protective factor for type 2 diabetes mellitus (T2DM), it would be interesting to know if T2DM patients could benefit from tea. Because of small sample sizes and inconsistent results of previous studies, we performed this meta-analysis to reevaluate the effects of tea or tea extract on all available outcomes in patients with T2DM. We systematically searched electronic databases of PubMed, Cochrane Library and EMBASE to identify randomized controlled trials of tea in T2DM patients up to January 2015. Weight mean differences for the changes in all outcomes were pooled by Review Manager 5.2 (Cochrane Collaboration, Oxford, England). A total of ten trials including 608 subjects were identified. The meta-analysis found that tea could alleviate the decrease of fasting blood insulin [1.30 U/L, 95% CI (0.36, 2.24)], and reduced waist circumference only in more than 8-week intervention [-2.70 cm, 95% CI (-4.72, -0.69)], whereas there were no statistically significant differences with regard to homeostasis model of insulin resistance 0.38 (-0.18, 0.95), fasting blood glucose -0.05 mmol/L (-0.51, 0.40), low density lipoprotein-cholesterol 0.07 mmol/L (-0.15, 0.29), high density lipoprotein-cholesterol 0.01 mmol/L (-0.08, 0.09), body mass index -0.15 kg/m(2) (-0.50, 0.21), SBP 0.35 mmHg (-3.54, 4.24), DBP -1.02 mmHg (-3.53, 1.48), triglycerides -0.11 mmol/L (-0.28, 0.05) and fasting cholesterol -0.05 mmol/L (-0.20, 0.11) in patients with T2DM, and leptin, ADPN, CRE and UA were also non-significant. The intervention of tea or tea extraction could maintain a stable fasting blood insulin and reduce waist circumference in the T2DM patients; however, the effects on other outcomes were not significant. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Effects of processing parameters on the caffeine extraction yield during decaffeination of black tea using pilot-scale supercritical carbon dioxide extraction technique.

PubMed

Ilgaz, Saziye; Sat, Ihsan Gungor; Polat, Atilla

2018-04-01

In this pilot-scale study supercritical carbon dioxide (SCCO 2 ) extraction technique was used for decaffeination of black tea. Pressure (250, 375, 500 bar), extraction time (60, 180, 300 min), temperature (55, 62.5, 70 °C), CO 2 flow rate (1, 2, 3 L/min) and modifier quantity (0, 2.5, 5 mol%) were selected as extraction parameters. Three-level and five-factor response surface methodology experimental design with a Box-Behnken type was employed to generate 46 different processing conditions. 100% of caffeine from black tea was removed under two different extraction conditions; one of which was consist of 375 bar pressure, 62.5 °C temperature, 300 min extraction time, 2 L/min CO 2 flow rate and 5 mol% modifier concentration and the other was composed of same temperature, pressure and extraction time conditions with 3 L/min CO 2 flow rate and 2.5 mol% modifier concentration. Results showed that extraction time, pressure, CO 2 flow rate and modifier quantity had great impact on decaffeination yield.

Tea-induced improvement of endothelial function in humans: No role for epigallocatechin gallate (EGCG).

PubMed

Lorenz, Mario; Rauhut, Franziska; Hofer, Christine; Gwosc, Stefanie; Müller, Eda; Praeger, Damaris; Zimmermann, Benno F; Wernecke, Klaus-Dieter; Baumann, Gert; Stangl, Karl; Stangl, Verena

2017-05-23

Consumption of tea is inversely associated with cardiovascular diseases. However, the active compound(s) responsible for the protective effects of tea are unknown. Although many favorable cardiovascular effects in vitro are mediated by epigallocatechin gallate (EGCG), its contribution to the beneficial effects of tea in vivo remains unresolved. In a randomised crossover study, a single dose of 200 mg EGCG was applied in three different formulas (as green tea beverage, green tea extract (GTE), and isolated EGCG) to 50 healthy men. Flow-mediated dilation (FMD) and endothelial-independent nitro-mediated dilation (NMD) was measured before and two hours after ingestion. Plasma levels of tea compounds were determined after each intervention and correlated with FMD. FMD significantly improved after consumption of green tea containing 200 mg EGCG (p < 0.01). However, GTE and EGCG had no significant effect on FMD. NMD did not significantly differ between interventions. EGCG plasma levels were highest after administration of EGCG and lowest after consumption of green tea. Plasma levels of caffeine increased after green tea consumption. The results show that EGCG is most likely not involved in improvement of flow-mediated dilation by green tea. Instead, other tea compounds, metabolites or combinations thereof may play a role.

Cardiovascular effects of black tea and nicotine alone or in combination against experimental induced heart injury.

PubMed

Joukar, Siyavash; Bashiri, Hamideh; Dabiri, Shahriar; Ghotbi, Payam; Sarveazad, Arash; Divsalar, Kouros; Joukar, Farzin; Abbaszadeh, Mahsa

2012-06-01

The present study was designed to elucidate the outcome of subchronic co-administration of black tea and nicotine on cardiovascular performance and whether these substances could modulate the isoproterenol-induced cardiac injury. Animal groups were control, black tea, nicotine and black tea plus nicotine. Test groups received nicotine (2 mg/kg s.c.) and black tea brewed (p.o.) each alone and in combination for 4 weeks. On the 28th day, myocardial damage was induced by isoproterenol (50 mg/kg i.p.), and blood samples were taken. On day 29, after hemodynamic parameters recording, hearts were removed for histopathological evaluation. Tea or nicotine consumption had no significant effects on hemodynamic indices of animals without heart damage. When the cardiac injury was induced, tea consumption maintained the maximum dp/dt, and nicotine significantly decreased the pressure-rate product. Moreover, severity of heart lesions was lower in the presence of nicotine or black tea. Concomitant use of these materials did not show extra effects on mentioned parameters more than the effect of each of them alone. The results suggest that subchronic administration of black tea or nicotine for a period of 4 weeks may have a mild cardioprotective effect, while concomitant use of these materials cannot intensify this beneficial effect.

Properties and antioxidant action of actives cassava starch films incorporated with green tea and palm oil extracts.

PubMed

Perazzo, Kátya Karine Nery Carneiro Lins; Conceição, Anderson Carlos de Vasconcelos; dos Santos, Juliana Caribé Pires; Assis, Denilson de Jesus; Souza, Carolina Oliveira; Druzian, Janice Izabel

2014-01-01

There is an interest in the development of an antioxidant packaging fully biodegradable to increase the shelf life of food products. An active film from cassava starch bio-based, incorporated with aqueous green tea extract and oil palm colorant was developed packaging. The effects of additives on the film properties were determined by measuring mechanical, barrier and thermal properties using a response surface methodology design experiment. The bio-based films were used to pack butter (maintained for 45 days) under accelerated oxidation conditions. The antioxidant action of the active films was evaluated by analyzing the peroxide index, total carotenoids, and total polyphenol. The same analysis also evaluated unpacked butter, packed in films without additives and butter packed in LDPE films, as controls. The results suggested that incorporation of the antioxidants extracts tensile strength and water vapor barrier properties (15 times lower) compared to control without additives. A lower peroxide index (231.57%), which was significantly different from that of the control (p<0.05), was detected in products packed in film formulations containing average concentration of green tea extracts and high concentration of colorant. However, it was found that the high content of polyphenols in green tea extract can be acted as a pro-oxidant agent, which suggests that the use of high concentration should be avoided as additives for films. These results support the applicability of a green tea extract and oil palm carotenoics colorant in starch films totally biodegradable and the use of these materials in active packaging of the fatty products.

Properties and Antioxidant Action of Actives Cassava Starch Films Incorporated with Green Tea and Palm Oil Extracts

PubMed Central

Perazzo, Kátya Karine Nery Carneiro Lins; Conceição, Anderson Carlos de Vasconcelos; dos Santos, Juliana Caribé Pires; Assis, Denilson de Jesus; Souza, Carolina Oliveira; Druzian, Janice Izabel

2014-01-01

There is an interest in the development of an antioxidant packaging fully biodegradable to increase the shelf life of food products. An active film from cassava starch bio-based, incorporated with aqueous green tea extract and oil palm colorant was developed packaging. The effects of additives on the film properties were determined by measuring mechanical, barrier and thermal properties using a response surface methodology design experiment. The bio-based films were used to pack butter (maintained for 45 days) under accelerated oxidation conditions. The antioxidant action of the active films was evaluated by analyzing the peroxide index, total carotenoids, and total polyphenol. The same analysis also evaluated unpacked butter, packed in films without additives and butter packed in LDPE films, as controls. The results suggested that incorporation of the antioxidants extracts tensile strength and water vapor barrier properties (15 times lower) compared to control without additives. A lower peroxide index (231.57%), which was significantly different from that of the control (p<0.05), was detected in products packed in film formulations containing average concentration of green tea extracts and high concentration of colorant. However, it was found that the high content of polyphenols in green tea extract can be acted as a pro-oxidant agent, which suggests that the use of high concentration should be avoided as additives for films. These results support the applicability of a green tea extract and oil palm carotenoics colorant in starch films totally biodegradable and the use of these materials in active packaging of the fatty products. PMID:25251437

Modelling and simulation of a moving interface problem: freeze drying of black tea extract

NASA Astrophysics Data System (ADS)

Aydin, Ebubekir Sıddık; Yucel, Ozgun; Sadikoglu, Hasan

2017-06-01

The moving interface separates the material that is subjected to the freeze drying process as dried and frozen. Therefore, the accurate modeling the moving interface reduces the process time and energy consumption by improving the heat and mass transfer predictions during the process. To describe the dynamic behavior of the drying stages of the freeze-drying, a case study of brewed black tea extract in storage trays including moving interface was modeled that the heat and mass transfer equations were solved using orthogonal collocation method based on Jacobian polynomial approximation. Transport parameters and physical properties describing the freeze drying of black tea extract were evaluated by fitting the experimental data using Levenberg-Marquardt algorithm. Experimental results showed good agreement with the theoretical predictions.

Separation and purification of both tea seed polysaccharide and saponin from camellia cake extract using macroporous resin.

PubMed

Yang, Pengjie; Zhou, Mingda; Zhou, Chengyun; Wang, Qian; Zhang, Fangfang; Chen, Jian

2015-02-01

A novel method to separate and purify tea seed polysaccharide and tea seed saponin from camellia cake extract by macroporous resin was developed. Among four kinds of resins (AB-8, NKA-9, XDA-6, and D4020) tested, AB-8 macroporous resin possessed optimal separating capacity for the two substances and thus was selected for the separation, in which deionized water was used to elute tea seed polysaccharide, 0.25% NaOH solution to remove the undesired pigments, and 90% ethanol to elute tea seed saponin. Further dynamic adsorption/desorption experiments on AB-8 resin-based column chromatography were conducted to obtain the optimal parameters. Under optimal dynamic adsorption and desorption conditions, 18.7 and 11.8% yield of tea seed polysaccharide and tea seed saponin were obtained with purities of 89.2 and 96.0%, respectively. The developed method provides a potential approach for the large-scale production of tea seed polysaccharide and tea seed saponin from camellia cake. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Iodine-Induced Thyrotoxicosis After Ingestion of Kelp-Containing Tea

PubMed Central

Müssig, Karsten; Thamer, Claus; Bares, Roland; Lipp, Hans-Peter; Häring, Hans-Ulrich; Gallwitz, Baptist

2006-01-01

Complementary medication is en vogue and an increasing number of patients consume herbal medicine without reporting their use to physicians. We report a case of iodine-induced hyperthyroidism due to the ingestion of a kelp-containing tea. A 39-year-old woman with multinodular goiter presented with typical signs of hyperthyroidism, which was confirmed by endocrine tests. She was not exposed to iodinated radiocontrast media and did not take medications containing iodine, such as amiodarone. However, a detailed medical history revealed that she had been treated for a period of 4 weeks by a Chinese alternative practitioner with a herbal tea containing kelp because of her enlarged thyroid. The consumption of the tea was discontinued and an antithyroid drug therapy was initiated. Physicians should advise patients with underlying thyroid disease to avoid all complementary or alternative medications containing iodine. PMID:16808731

Performance and methane emissions in dairy cows fed oregano and green tea extracts as feed additives.

PubMed

Kolling, G J; Stivanin, S C B; Gabbi, A M; Machado, F S; Ferreira, A L; Campos, M M; Tomich, T R; Cunha, C S; Dill, S W; Pereira, L G R; Fischer, V

2018-05-01

Plant extracts have been proposed as substitutes for chemical feed additives due to their potential as rumen fermentation modifiers and because of their antimicrobial and antioxidant activities, possibly reducing methane emissions. This study aimed to evaluate the use of oregano (OR), green tea extracts (GT), and their association as feed additives on the performance and methane emissions from dairy between 28 and 87 d of lactation. Thirty-two lactating dairy cows, blocked into 2 genetic groups: 16 Holstein cows and 16 crossbred Holstein-Gir, with 522.6 ± 58.3 kg of body weight, 57.2 ± 20.9 d in lactation, producing 27.5 ± 5.0 kg/cow of milk and with 3.1 ± 1.8 lactations were evaluated (means ± standard error of the means). Cows were allocated into 4 treatments: control (CON), without plant extracts in the diet; oregano extract (OR), with the addition of 0.056% of oregano extract in the dry matter (DM) of the diet; green tea (GT), with the addition of 0.028% of green tea extract in the DM of the diet; and mixture, with the addition of 0.056% oregano extract and 0.028% green tea extract in the DM of the diet. The forage-to-concentrate ratio was 60:40. Forage was composed of corn silage (94%) and Tifton hay (6%); concentrate was based on ground corn and soybean meal. Plant extracts were supplied as powder, which was previously added and homogenized into 1 kg of concentrate in natural matter, top-dressed onto the total mixed diet. No treatment by day interaction was observed for any of the evaluated variables, but some block by treatment interactions were significant. In Holstein cows, the mixture treatment decreased gross energy and tended to decrease the total-tract apparent digestibility coefficient for crude protein and total digestible nutrients when compared with OR. During the gas measurement period, GT and OR increased the digestible fraction of the ingested DM and decreased CH 4 expressed in grams per kilogram of digestible DMI compared with CON. The use

Identification and quantitation of alkaloids in coca tea

PubMed Central

Jenkins, Amanda J.; Llosa, Teobaldo; Montoya, Ivan

2008-01-01

The consumption of coca tea is a common occurrence in many South American countries. The tea is often packaged in individual servings as tea bags which contain approximately 1 g of plant material. The consumption of coca tea leads to ingestion of cocaine and other alkaloids: however, there is little information available regarding the pharmacological or toxicological effects that result from consumption of coca tea. We performed a series of studies with coca tea bags from two South American countries, Peru and Bolivia. The alkaloidal content of the ‘coca leaf’ in coca tea bags was determined by two different extraction methods: Soxhlet extraction with methanol (exhaustive extraction), and mechanical agitation with methanol. Extracts were purified by solid-phase extraction (SPE) followed by analysis by gas chromatography/mass spectrometry (GC/MS). Coca tea prepared from Peruvian and Bolivian coca tea bags was also analyzed by SPE-GC/MS assay. In addition, urine specimens were analyzed from an individual who consumed one cup of Peruvian coca tea and one cup of Bolivian coca tea on separate occasions. Urine samples were analyzed by immunoassay (TDxR) and SPE-GC/MS. Analysis of coca tea bags and coca tea indicated that cocaine, benzoylecgonine, ecgonine methyl ester and trans-cinnamoylcocaine were present in varying quantities. With exhaustive extraction, an average of 5.11 mg, and 4.86 mg of cocaine per tea bag were found in coca leaf from Peru and Bolivia, respectively. The average amounts of benzoylecgonine and ecgonine methyl ester in Peruvian coca leaf were 0.11 and 1.15 mg, and in Bolivian coca leaf were 0.12 and 2.93 mg per tea bag, respectively. trans-Cinnamoylcocaine was found in trace amounts in Peruvian tea bags and 0.16 mg/tea bag of Bolivian tea. When tea was prepared, an average of 4.14 mg of cocaine was present in a cup of Peruvian coca tea and 4.29 mg of cocaine was present in Bolivian tea. Following the consumption of a cup of Peruvian tea by one

Green synthesis palladium nanoparticles mediated by white tea (Camellia sinensis) extract with antioxidant, antibacterial, and antiproliferative activities toward the human leukemia (MOLT-4) cell line.

PubMed

Azizi, Susan; Mahdavi Shahri, Mahnaz; Rahman, Heshu Sulaiman; Rahim, Raha Abdul; Rasedee, Abdullah; Mohamad, Rosfarizan

2017-01-01

Among nanoparticles used for medical applications, palladium nanoparticles (PdNPs) are among the least investigated. This study was undertaken to develop PdNPs by green synthesis using white tea (W.tea; Camellia sinensis ) extract to produce the Pd@W.tea NPs. The Pd@W.tea NPs were characterized by UV-vis spectroscopy and X-ray diffractometry, and evaluated with transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The Pd@W.tea NPs were spherical (size 6-18 nm) and contained phenols and flavonoids acquired from the W.tea extract. Pd@W.tea NPs has good 1-diphenyl-2-picrylhydrazyl (DPPH), OH, and NO-scavenging properties as well as antibacterial effects toward Staphylococcus epidermidis and Escherichia coli . MTT assay showed that Pd@W.tea NPs (IC 50 =0.006 μM) were more antiproliferative toward the human leukemia (MOLT-4) cells than the W.tea extract (IC 50 =0.894 μM), doxorubicin (IC 50 =2.133 μM), or cisplatin (IC 50 =0.013 μM), whereas they were relatively innocuous for normal human fibroblast (HDF-a) cells. The anticancer cell effects of Pd@W.tea NPs are mediated through the induction of apoptosis and G2/M cell-cycle arrest.

Comparative assessment of antibacterial efficacy of aqueous extract of commercially available black, green, and lemon tea: an in vitro study

PubMed Central

Arun, S. Dodamani; Minal, M. Kshirsagar; Karibasappa, G. N.; Prashanth, V. K.; Girija, A. Dodamani; Harish, C. Jadhav

2017-01-01

Objectives: The objective of this study is to determine and compare antibacterial efficacy of aqueous extracts of black, green, and lemon tea of a commercially available brand. Materials and Methods: The well-diffusion method was used to evaluate the antibacterial efficacy of commercially available black tea, green tea, and lemon tea at three different concentrations (1.5 g, 5 g, and 7.5 g) against Streptococcus mutans and Lactobacillus acidophilus. After incubation in appropriate culture medium, diameter of zone of inhibition was measured to assess the antibacterial efficacy of tea. Results: Maximum zone of inhibition was found with lemon tea (27 mm) followed by green tea (26 mm) and black tea (13 mm) against S. mutans and L. acidophilus. Zone of inhibition was highest at 7.5 g concentration (1 and half tea spoon) for lemon tea followed by green tea and black tea. Results were statistically analyzed with the analysis of variance (ANOVA). For pairwise intergroup multiple comparisons, bonferroni test was applied. The difference between black tea, green tea, and lemon tea were statistically significant (P < 0.001) at 5% of level of significance. Conclusion: Lemon tea at 7.5 g concentration was more effective followed by green tea and black tea against S. mutans and L. acidophilus. PMID:29085267

Antigenotoxic and Apoptotic Activity of Green Tea Polyphenol Extracts on Hexavalent Chromium-Induced DNA Damage in Peripheral Blood of CD-1 Mice: Analysis with Differential Acridine Orange/Ethidium Bromide Staining

PubMed Central

García-Rodríguez, María del Carmen; Carvente-Juárez, Megumi Monserrat; Altamirano-Lozano, Mario Agustín

2013-01-01

This study was conducted to investigate the modulating effects of green tea polyphenols on genotoxic damage and apoptotic activity induced by hexavalent chromium [Cr (VI)] in CD-1 mice. Animals were divided into the following groups: (i) injected with vehicle; (ii) treated with green tea polyphenols (30 mg/kg) via gavage; (iii) injected with CrO3 (20 mg/kg) intraperitoneally; (iv) treated with green tea polyphenols in addition to CrO3. Genotoxic damage was evaluated by examining micronucleated polychromatic erythrocytes (MN-PCEs) obtained from peripheral blood at 0, 24, 48, and 72 h after treatment. Induction of apoptosis and cell viability were assessed by differential acridine orange/ethidium bromide (AO/EB) staining. Treatment of green tea polyphenols led to no significant changes in the MN-PCEs. However, CrO3 treatment significantly increased MN-PCEs at 24 and 48 h after injection. Green tea polyphenols treatment prior to CrO3 injection led to a decrease in MN-PCEs compared to the group treated with CrO3 only. The average of apoptotic cells was increased at 48 h after treatment compared to control mice, suggesting that apoptosis could contribute to eliminate the DNA damaged cells induced by Cr (VI). Our findings support the proposed protective effects of green tea polyphenols against the genotoxic damage induced by Cr (VI). PMID:24363823

Phytochemical Screening and Acute Oral Toxicity Study of Java Tea Leaf Extracts

PubMed Central

Safinar Ismail, Intan; Azam, Amalina Ahmad; Abas, Faridah; Shaari, Khozirah; Sulaiman, Mohd Roslan

2015-01-01

The term Java tea refers to the decoction of Orthosiphon stamineus (OS) Benth (Lamiaceae) leaves, which are widely consumed by the people in Europe and South East Asian countries. The OS leaves are known for their use in traditional medicinal systems as a prophylactic and curative agent for urinary stone, diabetes, and hypertension and also as a diuretic agent. The present study was aimed at evaluating its possible toxicity. Herein, the major phytochemical constituents of microwave dried OS leaf, which is the common drying process for tea sachets in the market, were also identified. The acute oral toxicity test of aqueous, 50% aqueous ethanolic, and ethanolic extracts of OS was performed at a dose of 5000 mg/Kg body weight of Sprague-Dawley rats. During the 14-day study, the animals were observed for any mortality, behavioral, motor-neuronal abnormalities, body weight, and feed-water consumption pattern. The hematological and serum biochemical parameters to assess the kidney and liver functions were carried out, along with the histological analysis of these organs. It was found that all microwave dried OS leaf extracts did not cause any toxic effects or mortality at the administered dose. No abnormality was noticed in all selected parameters in rats of both sexes as compared with their respective control groups. Thus, the possible oral lethal dose for microwave dried Java tea leaves is more than 5000 mg/Kg body weight. PMID:26819955

Green tea extract as a local drug therapy on periodontitis patients with diabetes mellitus: A randomized case-control study.

PubMed

Gadagi, Jayaprakash S; Chava, Vijay K; Reddy, Venkata Ramesh

2013-03-01

The green tea extract is a naturally occurring product having beneficial effects that counteract with the pathobiological features of periodontitis and diabetes mellitus. Hence, the present study was aimed at incorporation of green tea extract into hydroxylpropyl methylcellulose and investigates its efficacy in chronic periodontitis patients associated with and without diabetes mellitus. For the in vitro study, formulation of green tea strips and placebo strips, and analysis of drug release pattern from the green tea strips at different time intervals were performed. For the in vivo study, 50 patients (20-65 years), including 25 systemically healthy patients with chronic periodontitis (group 1) and 25 diabetic patients with chronic periodontitis (group 2) were enrolled. In each patient, test and control sites were identified for the placement of green tea and placebo strips, respectively. Gingival Index (GI), Probing Pocket Depth (PPD), and Clinical Attachment Level (CAL) were examined at baseline, first, second, third, and fourth weeks. Microbiological analysis for Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans was performed at baseline and fourth week. The in vitro study showed 10.67% green tea release at 30 min; thereafter, a slow release was noted till 120 min. Both groups showed significant reduction in GI scores at the test sites. Group 1 showed significant (P < 0.001) PPD reduction at different time intervals at the test sites. However, group 2 showed significant reduction from baseline (5.30 ± 0.70) to fourth week (3.5 ± 0.97). Statistically significant gain in CAL at the test sites was observed both in group 1 (1.33 mm) and group 2 (1.43 mm). The prevalence of P. gingivalis in group 1 test sites was significantly reduced from baseline (75%) to fourth week (25%). Local drug delivery using green tea extract could be used as an adjunct in the treatment of chronic periodontitis in diabetic and non-diabetic individuals.

The potential role of polyphenols in the modulation of skin cell viability by Aspalathus linearis and Cyclopia spp. herbal tea extracts in vitro.

PubMed

Magcwebeba, Tandeka Unathi; Riedel, Sylvia; Swanevelder, Sonja; Swart, Pieter; De Beer, Dalene; Joubert, Elizabeth; Andreas Gelderblom, Wentzel Christoffel

2016-11-01

The relationship between polyphenol constituents, antioxidant properties of aqueous and methanol extracts of green tea (Camellia sinensis), the herbal teas, rooibos (Aspalathus linearis) and honeybush (Cyclopia spp.), against skin cell viability was investigated in vitro. The effect of extracts, characterised in terms of polyphenol content and antioxidant properties, on cell viability of premalignant, normal and malignant skin cells was determined. Phenolic composition, particularly high levels of potent antioxidants, of rooibos and green tea methanol extracts was associated with a strong reduction in cell viability specifically targeting premalignant cells. In contrast, the aqueous extracts of Cyclopia spp. were more effective in reducing cell viability. This correlated with a relatively high flavanol/proanthocyanidin content and ABTS radical cation scavenging capacity. The major green tea flavanol (epigallocatechin gallate) and rooibos dihydrochalcone (aspalathin) exhibited differential effects against cell viability, while the major honeybush xanthone (mangiferin) and flavanone (hesperidin) lacked any effect presumably due to a cytoprotective effect. The underlying mechanisms against skin cell viability are likely to involve mitochondrial dysfunction resulting from polyphenol-iron interactions. The polyphenol constituents and antioxidant parameters of herbal tea extracts are useful tools to predict their activity against skin cell survival in vitro and potential chemopreventive effects in vivo. © 2016 Royal Pharmaceutical Society.

Black Tea High-Molecular-Weight Polyphenol-Rich Fraction Promotes Hypertrophy during Functional Overload in Mice.

PubMed

Aoki, Yuki; Ozawa, Tetsuo; Takemasa, Tohru; Numata, Osamu

2017-03-29

Mitochondria activation factor (MAF) is a high-molecular-weight polyphenol extracted from black tea that stimulates training-induced 5' adenosine monophosphate-activated protein kinase (AMPK) activation and improves endurance capacity. Originally, MAF was purified from black tea using butanol and acetone, making it unsuitable for food preparation. Hence, we extracted a MAF-rich sample "E80" from black tea, using ethanol and water only. Here, we examined the effects of E80 on resistance training. Eight-week old C57BL/6 mice were fed with a normal diet or a diet containing 0.5% E80 for 4, 7 and 14 days under conditions of functional overload. It was found that E80 administration promoted overload-induced hypertrophy and induced phosphorylation of the Akt/mammalian target of rapamycin (mTOR) pathway proteins, such as Akt, P70 ribosomal protein S6 kinase (p70S6K), and S6 in the plantaris muscle. Therefore, functional overload and E80 administration accelerated mTOR signaling and increased protein synthesis in the muscle, thereby inducing hypertrophy.

Effect of gamma radiation on antioxidant capacity of green tea, yerba mate, and chamomile tea as evaluated by different methods

NASA Astrophysics Data System (ADS)

Gerolis, Luanai Grazieli Luquini; Lameiras, Fernando Soares; Krambrock, Klaus; Neves, Maria Jose.

2017-01-01

Tea is a traditional plant extract with important cultural ties. It is the most widely consumed beverage in the world. Tea consumption has some health benefits including antioxidant stimulus. Gamma radiation is currently used to control of postharvest pathogens on tea herb. However, free radicals can be generated, which consumes antioxidant molecules. A positive relation was found between radiation doses used and free radicals generation in green tea (Camellia sinensis), yerba mate (Ilex paraguariensis), and chamomile tea (Matricaria recutita). Total antioxidant capacity (TAC) of aqueous and methanol extracts of these herbs was determined by various methods to compare the effect of irradiation of herb on antioxidant capacity of the extracts. TAC was evaluated by measuring: total phenols (decreased with irradiation in mate and green teas), total flavonoids (stable in aqueous extracts and decreased with irradiation in methanol extract of mate and chamomile), Trolox equivalent or ABTS (unchanged under irradiation), DPPH* scavenging capacity (stable on aqueous extract but diminished in methanol extract after irradiation), β carotene/acid linoleic ability (stable with the exception of chamomile tea that increased after irradiation) and, capacity to chelate ferrous ions (unchanged with irradiation). In conclusion, gamma irradiation reduced the capacity of some antioxidants but preserved the capacity of others. This study showed that one isolated test does not suffice to perform this evaluation reliably, which is a reflection of the diversity and complexity of the effects of irradiation on antioxidant molecules present in different samples.

Evanescent wave sensing and absorption analysis of herbal tea floral extracts in the presence of silver metal complexes

NASA Astrophysics Data System (ADS)

Priyamvada, V. C.; Radhakrishnan, P.

2017-06-01

Fiber optic evanescent wave sensors are used for studying the absorption properties of biochemical samples. The studies give precise information regarding the actual ingredients of the samples. Recent studies report the corrosion of silver in the presence glucose dissolved in water and heated to a temperature of 70°C. Based on this report evanescent absorption studies are carried out in hibiscus herbal tea floral extracts in the presence of silver metal complexes. These studies can also lead to the evaluation of the purity of the herbal tea extract.

Potential protection of green tea polyphenols against 1800 MHz electromagnetic radiation-induced injury on rat cortical neurons.

PubMed

Liu, Mei-Li; Wen, Jian-Qiang; Fan, Yu-Bo

2011-10-01

Radiofrequency electromagnetic fields (EMF) are harmful to public health, but the certain anti-irradiation mechanism is not clear yet. The present study was performed to investigate the possible protective effects of green tea polyphenols against electromagnetic radiation-induced injury in the cultured rat cortical neurons. In this study, green tea polyphenols were used in the cultured cortical neurons exposed to 1800 MHz EMFs by the mobile phone. We found that the mobile phone irradiation for 24 h induced marked neuronal cell death in the MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl-tetrazolium bromide) and TUNEL (TdT mediated biotin-dUTP nicked-end labeling) assay, and protective effects of green tea polyphenols on the injured cortical neurons were demonstrated by testing the content of Bcl-2 Assaciated X protein (Bax) in the immunoprecipitation assay and Western blot assay. In our study results, the mobile phone irradiation-induced increases in the content of active Bax were inhibited significantly by green tea polyphenols, while the contents of total Bax had no marked changes after the treatment of green tea polyphenols. Our results suggested a neuroprotective effect of green tea polyphenols against the mobile phone irradiation-induced injury on the cultured rat cortical neurons.

Development of new antioxidant active packaging films based on ethylene vinyl alcohol copolymer (EVOH) and green tea extract.

PubMed

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.

Chemical composition and hepatoprotective effects of polyphenol-rich extract from Houttuynia cordata tea.

PubMed

Tian, Lingmin; Shi, Xiaolong; Yu, Linhong; Zhu, Jiao; Ma, Rui; Yang, Xingbin

2012-05-09

This study was designed to investigate the antioxidant activity, hepatoprotective effect, and phenolic composition of the ethyl acetate fraction (EAF) extracted from Houttuynia cordata tea. EAF was shown to exhibit strong ferric-reducing antioxidant power (FRAP) and scavenging activity against DPPH radical in vitro, and the antioxidant effects were further verified by suppressing CCl₄-induced oxidative stress in mouse liver at three tested doses of EAF (250, 500, and 1000 mg/kg bw). Pretreatment with EAF (1000 mg/kg bw) prior to CCl₄ administration significantly (p < 0.001) decreased the CCl₄-elevated levels of serum AST, ALT, alkaline phosphatase, total bilirubin, and hepatic MDA in mice and prevented the increases in GSH, SOD, and CAT caused by CCl₄. HPLC analysis revealed that three predominantly polyphenolic compounds present in EAF were quercitrin (111.7 μg/mg), quercetin (43.8 μg/mg), and hyperoside (29.1 μg/mg). These results combined with liver histopathology indicate that EAF possesses a significant protective effect against acute hepatotoxicity induced by CCl₄, which may be due to the strong antioxidant activity of phenolic components.

Capsule shell material impacts the in vitro disintegration and dissolution behaviour of a green tea extract.

PubMed

Glube, Natalie; Moos, Lea von; Duchateau, Guus

2013-01-01

In vitro disintegration and dissolution are routine methods used to assess the performance and quality of oral dosage forms. The purpose of the current work was to determine the potential for interaction between capsule shell material and a green tea extract and the impact it can have on the release. A green tea extract was formulated into simple powder-in-capsule formulations of which the capsule shell material was either of gelatin or HPMC origin. The disintegration times were determined together with the dissolution profiles in compendial and biorelevant media. All formulations disintegrated within 30 min, meeting the USP criteria for botanical formulations. An immediate release dissolution profile was achieved for gelatin capsules in all media but not for the specified HPMC formulations. Dissolution release was especially impaired for HPMCgell at pH 1.2 and for both HPMC formulations in FeSSIF media suggesting the potential for food interactions. The delayed release from studied HPMC capsule materials is likely attributed to an interaction between the catechins, the major constituents of the green tea extract, and the capsule shell material. An assessment of in vitro dissolution is recommended prior to the release of a dietary supplement or clinical trial investigational product to ensure efficacy.

Nutrient intake, digestibility and performance of Gaddi kids supplemented with tea seed or tea seed saponin extract.

PubMed

Kumar, M; Kannan, A; Bhar, R; Gulati, A; Gaurav, A; Sharma, V K

2017-04-01

An experiment was conducted to determine the nutrient intake, digestibility, microbial protein synthesis, haemato-biochemical attributes, immune response and growth performance of Gaddi kids fed with oat fodder based basal diet supplemented with either tea seed or tea seed saponin (TSS) extract. Eighteen male kids, 7.03±0.16 months of age and 19.72±0.64 kg body weight, were distributed into three groups, T 0 (control), T 1 , and T 2 , consisting of 6 animals each in a completely randomized design. The kids were fed a basal diet consisting of concentrate mixture and oat fodder (50:50). Animals in group III (T 2 ) were supplemented with TSS at 0.4% of dry matter intake (DMI), and group II (T 1 ) were supplemented with tea seed at 2.6% of DMI to provide equivalent dose of TSS as in T 2 . Two metabolism trials were conducted, 1st after 21 days and 2nd after 90 days of feeding to evaluate the short term and long term effects of supplementation. The tea seed (T 1 ) or TSS (T 2 ) supplementation did not affect DMI as well as the digestibility of dry matter, organic matter, crude protein, neutral detergent fibre, and acid detergent fibre. Nutritive value of diet and plane of nutrition were also comparable for both the periods. However, the average daily gain and feed conversion ratio (FCR) were improved (p<0.05) for T 1 and T 2 as compared to T 0 . The microbial protein supply was also higher (p<0.05) for T 1 and T 2 for both the periods. There was no effect of supplementation on most blood parameters. However, the triglyceride and low density lipoprotein cholesterol levels decreased (p<0.05) and high density lipoprotein-cholesterol level increased (p<0.05) in T 2 as compared with T 0 and T 1 . Supplementation also did not affect the cell mediated and humoral immune response in goats. Tea seed at 2.6% of DMI and TSS at 0.4% DMI can be fed to Gaddi goats to improve growth rate, FCR and microbial protein synthesis.

Nutrient intake, digestibility and performance of Gaddi kids supplemented with tea seed or tea seed saponin extract

PubMed Central

Kumar, M.; Kannan, A.; Bhar, R.; Gulati, A.; Gaurav, A.; Sharma, V. K.

2017-01-01

Objective An experiment was conducted to determine the nutrient intake, digestibility, microbial protein synthesis, haemato-biochemical attributes, immune response and growth performance of Gaddi kids fed with oat fodder based basal diet supplemented with either tea seed or tea seed saponin (TSS) extract. Methods Eighteen male kids, 7.03±0.16 months of age and 19.72±0.64 kg body weight, were distributed into three groups, T0 (control), T1, and T2, consisting of 6 animals each in a completely randomized design. The kids were fed a basal diet consisting of concentrate mixture and oat fodder (50:50). Animals in group III (T2) were supplemented with TSS at 0.4% of dry matter intake (DMI), and group II (T1) were supplemented with tea seed at 2.6% of DMI to provide equivalent dose of TSS as in T2. Two metabolism trials were conducted, 1st after 21 days and 2nd after 90 days of feeding to evaluate the short term and long term effects of supplementation. Results The tea seed (T1) or TSS (T2) supplementation did not affect DMI as well as the digestibility of dry matter, organic matter, crude protein, neutral detergent fibre, and acid detergent fibre. Nutritive value of diet and plane of nutrition were also comparable for both the periods. However, the average daily gain and feed conversion ratio (FCR) were improved (p<0.05) for T1 and T2 as compared to T0. The microbial protein supply was also higher (p<0.05) for T1 and T2 for both the periods. There was no effect of supplementation on most blood parameters. However, the triglyceride and low density lipoprotein cholesterol levels decreased (p<0.05) and high density lipoprotein-cholesterol level increased (p<0.05) in T2 as compared with T0 and T1. Supplementation also did not affect the cell mediated and humoral immune response in goats. Conclusion Tea seed at 2.6% of DMI and TSS at 0.4% DMI can be fed to Gaddi goats to improve growth rate, FCR and microbial protein synthesis. PMID:27608635

The Minnesota Green Tea Trial (MGTT), a randomized controlled trial of the efficacy of green tea extract on biomarkers of breast cancer risk: Study rationale, design, methods, and participant characteristics

PubMed Central

Samavat, Hamed; Dostal, Allison M.; Wang, Renwei; Bedell, Sarah; Emory, Tim H.; Ursin, Giske; Torkelson, Carolyn J.; Gross, Myron D.; Le, Chap T.; Yu, Mimi C.; Yang, Chung S.; Yee, Douglas; Wu, Anna H.; Yuan, Jian-Min; Kurzer, Mindy S.

2015-01-01

Purpose The Minnesota Green Tea Trial (MGTT) was a randomized, placebo-controlled, double-blinded trial investigating the effect of daily green tea extract consumption for 12 months on biomarkers of breast cancer risk. Methods Participants were healthy postmenopausal women at high risk of breast cancer due to dense breast tissue with differing catechol-O-methyltransferase (COMT) genotypes. The intervention was a green tea catechin extract containing 843.0 ± 44.0 mg/day epigallocatechin gallate or placebo capsules for one year. Annual digital screening mammograms were obtained at baseline and month 12, and fasting blood and 24-hour urine samples were provided at baseline, months 6, and 12. Primary endpoints included changes in percent mammographic density, circulating endogenous sex hormones and insulin-like growth factor axis proteins; secondary endpoints were changes in urinary estrogens and estrogen metabolites and circulating F2-isoprostanes, a biomarker of oxidative stress. Results The MGTT screened more than 100,000 mammograms and randomized 1075 participants based on treatment (green tea extract vs. placebo), stratified by COMT genotype activity (high COMT vs. low/intermediate COMT genotype activity). 937 women successfully completed the study and 138 dropped out (overall dropout rate= 12.8%). Conclusions In this paper we report the rationale, design, recruitment, participant characteristics, and methods for biomarker and statistical analyses. PMID:26206423

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

PubMed

Fujioka, Kouki; Iwamoto, Takeo; Shima, Hidekazu; Tomaru, Keiko; Saito, Hideki; Ohtsuka, Masaki; Yoshidome, Akihiro; Kawamura, Yuri; Manome, Yoshinobu

2016-04-11

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.

Effect of different types of tea on Streptococcus mutans: an in vitro study.

PubMed

Subramaniam, Priya; Eswara, Uma; Maheshwar Reddy, K R

2012-01-01

If tea can be shown to have an inhibitory effect on the growth of Streptococcus mutans there can be a basis for using it as an agent for reducing caries. The aim of the study was to determine the effect of aqueous and organic extracts of three types of tea (green, oolong, and black tea) on the growth of S. mutans. In vitro study. Qualitative and quantitative phytochemical analysis of the three types of tea was done. Organic extracts of methanol and ethanol and aqueous extracts (50% and 100%) of tea were prepared. Fifty microliters of these extracts were inoculated into wells prepared on Mueller-Hinton agar plates that had been previously smeared with S. mutans. The agar plates were incubated at 37΀C for 24 hours. A similar procedure was followed using 0.2% chlorhexidine, which served as the positive control. Analysis of variance (ANOVA), post hoc Tukey test, Student's 't ' test (two-tailed, dependent), and Student's 't' test (two-tailed, independent) were used for analysis of the data. All the phytochemicals were found to be higher in oolong tea. Both aqueous and organic extracts of oolong tea showed greatest zones of inhibition, followed by green tea and black tea. Aqueous extracts of oolong and green tea showed greater zone of inhibition than chlorhexidine. All the three types of tea inhibited growth of S. mutans. The greatest inhibition was observed with aqueous extract of oolong tea. Oolong tea extracts (aqueous and organic) showed a greater inhibitory effect on the growth of S. mutans than the other tea extracts .

Green Tea Extracts Epigallocatechin-3-gallate for Different Treatments

PubMed Central

Chu, Chenyu; Deng, Jia

2017-01-01

Epigallocatechin-3-gallate (EGCG), a component extracted from green tea, has been proved to have multiple effects on human pathological and physiological processes, and its mechanisms are discrepant in cancer, vascularity, bone regeneration, and nervous system. Although there are multiple benefits associated with EGCG, more and more challenges are still needed to get through. For example, EGCG shows low bioactivity via oral administration. This review focuses on effects of EGCG, including anti-cancer, antioxidant, anti-inflammatory, anticollagenase, and antifibrosis effects, to express the potential of EGCG and necessity of further studies in this field. PMID:28884125

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

PubMed Central

Tsai, Yin-Jieh; Chen, Bing-Huei

2016-01-01

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 apoptosis of PC-3 cells through decrease in B-cell lymphoma 2 (bcl-2) expression and increase in cytochrome c expression for activation of caspase-3, caspase-8, and

Protective activity of green tea against free radical- and glucose-mediated protein damage.

PubMed

Nakagawa, Takako; Yokozawa, Takako; Terasawa, Katsutoshi; Shu, Seiji; Juneja, Lekh Raj

2002-04-10

Protein oxidation and glycation are posttranslational modifications that are implicated in the pathological development of many age-related disease processes. This study investigated the effects of green tea extract, and a green tea tannin mixture and its components, on protein damage induced by 2,2'-azobis(2-amidinopropane) dihydrochloride (a free radical generator) and glucose in in vitro assay systems. We found that green tea extract can effectively protect against protein damage, and showed that its action is mainly due to tannin. In addition, it was shown that the chemical structures of tannin components are also involved in this activity, suggesting that the presence of the gallate group at the 3 position plays the most important role in the protective activity against protein oxidation and glycation, and that there is also a contribution by the hydroxyl group at the 5' position in the B ring and the sterical structure. These findings demonstrate the mechanisms of the usefulness of green tea in protein oxidation- and glycation-associated diseases.

Healing mechanisms of the hydroalcoholic extract and ethyl acetate fraction of green tea (Camellia sinensis (L.) Kuntze) on chronic gastric ulcers.

PubMed

Borato, Débora Gasparin; Scoparo, Camila Toledo; Maria-Ferreira, Daniele; da Silva, Luísa Mota; de Souza, Lauro Mera; Iacomini, Marcello; Werner, Maria Fernanda de Paula; Baggio, Cristiane Hatsuko

2016-03-01

Green tea is an infusion of unfermented leaves of Camellia sinensis (L.) Kuntze (Theaceae), traditionally used for the treatment of obesity, hypercholesterolemia, and gastric complaints. This study evaluated the mechanisms involved in the gastric ulcer healing of the hydroalcoholic extract from green tea (GEt), its ethyl acetate fraction, (GEAc) and epigallocatechin gallate (EGCG) using the model of acetic acid-induced gastric ulcer in rats. The chronic gastric ulcer was induced by application of 80 % acetic acid on serosal mucosa of rats. After 7 days of oral treatment with GEt and GEAc, the ulcer area, mucin content, inflammatory parameters (MPO and NAG), and antioxidant system (GSH and LOOH levels, SOD and GST activities) were evaluated. In vitro, the scavenging activity of GEt and GEAc were also measured. The antisecretory action was studied on the pylorus ligature method in rats. Oral treatment with GEt and GEAc reduced significantly the gastric ulcer area induced by acetic acid. The gastric ulcer healing was accompanied by increasing of mucin content, restoration of GSH levels and SOD activity, and reduction of MPO and LOOH levels. In addition, GEt and GEAc reduced the DPPH free radicals in vitro. Furthermore, the oral treatment of animals with GEt and GEAc did not alter the gastric acid secretion or cause signs of toxicity. Collectively, these results showed that GEt had a pronounced antiulcer effect, possibly through maintenance of mucin content and reduction of inflammation and oxidative stress. In addition, the compounds present in its ethyl acetate fraction could be responsible for the extract activity.

[Effect of green tea or green tea extract consumption on body weight and body composition; systematic review and meta-analysis].

PubMed

Baladia, Eduard; Basulto, Julio; Manera, María; Martínez, Rodrigo; Calbet, David

2014-03-01

Caffeine and catechins contained in green tea may have a thermogenic effect favoring weight and body fat loss. The aim of this study is to evaluate the magnitude of the effect of green tea or its extracts (caffeine and catechins) on body weight and body composition. A systematic review and meta-analysis was conducted to determine the magnitude of the effect of green tea or its extracts on body weight (kg), body mass index (BMI) (kg/m2), fat mass (%), and waist and hip circumference (cm). We included studies published between 2000 and 2013, retrieved from PubMed/Medline with the following characteristics: randomized controlled trials (RCTs) of parallel groups (intervention and placebo), randomized, double-blind, and a minimum 12-week follow-up, in healthy individuals of either gender, 18 years or older, with a BMI of 25-40 kg/m2. Quality and risk of bias was assessed for every included study, and the statistical analysis was performed with the Crochrane Collaboration RevMan 5.1.6 software, according to the random effects model with a confidence interval of 95% (95%). It was established that the effect was statistically significant at p < 0.05, and the homogeneity of the studies was assessed using the I2 index. The search strategy retrieved 154 studies, of which only five could be included in the quantitative analysis. The analysis revealed a not statistically significant mean difference (MD) in weight loss in the analyzed sample and subgroups: Asian individuals -0.81 kg (95% CI: -2.76 to 1.13; P = 0.41; I2 = 0%, n = 210), Caucasians -0.73 kg (95% CI: -3.22 to 1.75; P = 0.45; I2 = 0%; n = 91), as well as in the sample as a whole: -0.78 kg (95% CI: -2.31 to 0.75; P = 0.32; I2 = 0%; n = 301). No statistically significant decrease was revealed in BMI in the analyzed sample and subgroups: Asian individuals -0.65 (95% CI: -1.85 to 0.54; P = 0.29; I2 = 0%; n = 71), -0.21 Caucasians (95% CI: -0.96 to 0.53; P = 0.58; I2 = 22%; n = 91), as well as in the sample as a whole: -0

Pine Bark and Green Tea Concentrated Extracts: Antioxidant Activity and Comprehensive Characterization of Bioactive Compounds by HPLC–ESI-QTOF-MS

PubMed Central

Cádiz-Gurrea, María de la Luz; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio

2014-01-01

The consumption of polyphenols has frequently been associated with low incidence of degenerative diseases. Most of these natural antioxidants come from fruits, vegetables, spices, grains and herbs. For this reason, there has been increasing interest in identifying plant extract compounds. Polymeric tannins and monomeric flavonoids, such as catechin and epicatechin, in pine bark and green tea extracts could be responsible for the higher antioxidant activities of these extracts. The aim of the present study was to characterize the phenolic compounds in pine bark and green tea concentrated extracts using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC–ESI-QTOF-MS). A total of 37 and 35 compounds from pine bark and green tea extracts, respectively, were identified as belonging to various structural classes, mainly flavan-3-ol and its derivatives (including procyanidins). The antioxidant capacity of both extracts was evaluated by three complementary antioxidant activity methods: Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC). Higher antioxidant activity values by each method were obtained. In addition, total polyphenol and flavan-3-ol contents, which were determined by Folin–Ciocalteu and vanillin assays, respectively, exhibited higher amounts of gallic acid and (+)-catechin equivalents. PMID:25383680

Pine bark and green tea concentrated extracts: antioxidant activity and comprehensive characterization of bioactive compounds by HPLC-ESI-QTOF-MS.

PubMed

de la Luz Cádiz-Gurrea, María; Fernández-Arroyo, Salvador; Segura-Carretero, Antonio

2014-11-06

The consumption of polyphenols has frequently been associated with low incidence of degenerative diseases. Most of these natural antioxidants come from fruits, vegetables, spices, grains and herbs. For this reason, there has been increasing interest in identifying plant extract compounds. Polymeric tannins and monomeric flavonoids, such as catechin and epicatechin, in pine bark and green tea extracts could be responsible for the higher antioxidant activities of these extracts. The aim of the present study was to characterize the phenolic compounds in pine bark and green tea concentrated extracts using high-performance liquid chromatography coupled to electrospray ionization mass spectrometry (HPLC-ESI-QTOF-MS). A total of 37 and 35 compounds from pine bark and green tea extracts, respectively, were identified as belonging to various structural classes, mainly flavan-3-ol and its derivatives (including procyanidins). The antioxidant capacity of both extracts was evaluated by three complementary antioxidant activity methods: Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC). Higher antioxidant activity values by each method were obtained. In addition, total polyphenol and flavan-3-ol contents, which were determined by Folin-Ciocalteu and vanillin assays, respectively, exhibited higher amounts of gallic acid and (+)-catechin equivalents.

Hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats.

PubMed

Aloulou, Ahmed; Hamden, Khaled; Elloumi, Dhouha; Ali, Madiha Bou; Hargafi, Khaoula; Jaouadi, Bassem; Ayadi, Fatma; Elfeki, Abdelfattah; Ammar, Emna

2012-05-16

Diabetes has become a serious health problem and a major risk factor associated with troublesome health complications, such as metabolism disorders and liver-kidney dysfunctions. The inadequacies associated with conventional medicines have led to a determined search for alternative natural therapeutic agents. The present study aimed to investigate and compare the hypoglycemic and antilipidemic effects of kombucha and black tea, two natural drinks commonly consumed around the world, in surviving diabetic rats. Alloxan diabetic rats were orally supplied with kombucha and black tea at a dose of 5 mL/kg body weight per day for 30 days, fasted overnight, and sacrificed on the 31st day of the experiment. Their bloods were collected and submitted to various biochemical measurements, including blood glucose, cholesterol, triglcerides, urea, creatinine, transaminases, transpeptidase, lipase, and amylase activities. Their pancreases were isolated and processed to measure lipase and α-amylase activities and to perform histological analysis. The findings revealed that, compared to black tea, kombucha tea was a better inhibitor of α-amylase and lipase activities in the plasma and pancreas and a better suppressor of increased blood glucose levels. Interestingly, kombucha was noted to induce a marked delay in the absorption of LDL-cholesterol and triglycerides and a significant increase in HDL-cholesterol. Histological analyses also showed that it exerted an ameliorative action on the pancreases and efficiently protected the liver-kidney functions of diabetic rats, evidenced by significant decreases in aspartate transaminase, alanine transaminase, and gamma-glytamyl transpeptidase activities in the plasma, as well as in the creatinine and urea contents. The findings revealed that kombucha tea administration induced attractive curative effects on diabetic rats, particularly in terms of liver-kidney functions. Kombucha tea can, therefore, be considered as a potential strong

Hypoglycemic and antilipidemic properties of kombucha tea in alloxan-induced diabetic rats

PubMed Central

2012-01-01

Background Diabetes has become a serious health problem and a major risk factor associated with troublesome health complications, such as metabolism disorders and liver-kidney dysfunctions. The inadequacies associated with conventional medicines have led to a determined search for alternative natural therapeutic agents. The present study aimed to investigate and compare the hypoglycemic and antilipidemic effects of kombucha and black tea, two natural drinks commonly consumed around the world, in surviving diabetic rats. Methods Alloxan diabetic rats were orally supplied with kombucha and black tea at a dose of 5 mL/kg body weight per day for 30 days, fasted overnight, and sacrificed on the 31st day of the experiment. Their bloods were collected and submitted to various biochemical measurements, including blood glucose, cholesterol, triglcerides, urea, creatinine, transaminases, transpeptidase, lipase, and amylase activities. Their pancreases were isolated and processed to measure lipase and α-amylase activities and to perform histological analysis. Results The findings revealed that, compared to black tea, kombucha tea was a better inhibitor of α-amylase and lipase activities in the plasma and pancreas and a better suppressor of increased blood glucose levels. Interestingly, kombucha was noted to induce a marked delay in the absorption of LDL-cholesterol and triglycerides and a significant increase in HDL-cholesterol. Histological analyses also showed that it exerted an ameliorative action on the pancreases and efficiently protected the liver-kidney functions of diabetic rats, evidenced by significant decreases in aspartate transaminase, alanine transaminase, and gamma-glytamyl transpeptidase activities in the plasma, as well as in the creatinine and urea contents. Conclusions The findings revealed that kombucha tea administration induced attractive curative effects on diabetic rats, particularly in terms of liver-kidney functions. Kombucha tea can, therefore, be

Aluminum induced physiological and proteomic responses in tea (Camellia sinensis) roots and leaves.

PubMed

Xu, Qingshan; Wang, Yu; Ding, Zhaotang; Fan, Kai; Ma, Dexin; Zhang, Yongliang; Yin, Qi

2017-06-01

Tea (Camellia sinensis (L.) O. Kuntze), is an aluminum (Al) hyperaccumulator and grows well in acid soils. Although Al-induced growth of tea plant has been studied, the proteomic profiles of tea plants in response to Al are unclear. In the present study, the proteomic profiles in tea roots and leaves under Al stress were investigated using iTRAQ proteomics approach. In total, 755 and 1059 differentially expressed proteins were identified in tea roots and leaves, respectively. KEGG enrichment analysis showed that the differentially expressed proteins in roots were mainly involved in 11 pathways whereas those from leaves were mainly involved in 9 pathways. Abundance of most protein functions in glycolytic metabolism were enhanced in tea roots, and proteins involved in photosynthesis were stimulated in tea leaves. The protein ferulate-5-hydroxylase (F5H) in lignin biosynthetic pathway was down-regulated in both roots and leaves. Furthermore, antioxidant enzymes (ascorbate peroxidase, catalase and glutathione S-transferase) and citrate synthesis were accumulated in tea roots in response to Al. The results indicated that active photosynthesis and glycolysis as well as increased activities of antioxidant enzymes can be considered as a possible reason for the stimulatory effects of Al on the growth of tea plants. Additionally, the down-regulation of F5H and the binding of Al and phenolic acids may reduce the accumulation of lignin. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Anti-oxidative effects of rooibos tea extract on autoxidation and thermal oxidation of lipids.

PubMed

Fukasawa, Ryo; Kanda, Ayato; Hara, Setsuko

2009-01-01

Powdered rooibos tea extract (RTE), which is rich in polyphenols, is made from rooibos tea by freeze-drying. "Rooibos" is Afrikaans for "red bush," and the scientific name is "Aspalathus linearis." It is a broom-like member of the legume family of plants and is used to make an herbal tea which has been popular in South Africa for generations and is now consumed in many countries. In the present work, the anti-oxidative effect of RTE on oils and fats in autoxidation or thermal oxidation was studied, and it was confirmed that RTE has a very strong anti-oxidative effect on emulsifying oils owing to the water-soluble polyphenols such as rutin and quercetin contained in RTE. RTE was found to have a strong ability to quench radicals generated in the water phase, and to confer higher thermal stability against deep fat frying than tocopherol. But RTE showed little anti-oxidative effect on frying oil because of its lower oil-solubility.

Chemical compositions and antimicrobial activities of Athrixia phylicoides DC. (bush tea), Monsonia burkeana (special tea) and synergistic effects of both combined herbal teas.

PubMed

Tshivhandekano, Itani; Ntushelo, Khayalethu; Ngezimana, Wonder; Tshikalange, Thilivhali Emmanuel; Mudau, Fhatuwani Nixwell

2014-09-01

To determine the chemical compositions and evaluate the antimicrobial activity of bush tea (Athrixia phylicoides DC.), special tea (Monsonia burkeana) and synergy (combination of bush tea and special tea). Total polyphenols were determined using the methods reported by Singleton and Rossi (1965) and modified by Waterman and Mole (1994). Tannins were determined using vanillin HCL methods described by Prince et al. (1978). Total antioxidants were determined using the methods described by Awika et al. (2004). The micro dilution technique using 96-well micro-plates, as described by Eloff (1998) was used to obtain the minimum inhibition concentration (MIC) and minimum microbicidal concentration (MMC) values of the ethanol extracts against the microorganisms under study. The microbes strain used was Gram negative bacteria such as Escherichia coli, Klebsiella oxytoca, Proteus vulgaris, Serratia marcescens, Salmonella typhi, Klebsiella pneumonia; Gram positive bacteria such as Bacillus cereus, Staphylococcus aureus and a fungus Candida albicans. The results demonstrated that special tea contains significantly higher content of total polyphenols (8.34 mg/100 g) and total antioxidant (0.83 mg/100 g) as compared to bush tea [total polyphenols (6.41 mg/100g) and total antioxidant (0.63 mg/100g)] and combination of bush tea and special tea [total polyphenols (6.42 mg/100 g) and total antioxidant (0.64 mg/100 g)]. There was no significant difference in tannins between bush tea, special tea and synergy. The results of antimicrobial activity (MIC and MMC) demonstrated that the ethanol extracts of bush tea, special tea and synergy possessed antimicrobial activity against all microorganisms at different zones. The MIC of bush tea ranged from 1.56 to 12.50 mg/mL while the MMC ranged from 0.78 to 12.50 mg/mL. Special tea's MIC ranged from 0.39 to 12.50 mg/mL while the MMC ranged from 0.01 to 12.50 mg/mL. The MIC of synergy ranged from 3.13 to 12.50 mg/mL while the MMC ranged from 3

Effect of Kombucha, a fermented black tea in attenuating oxidative stress mediated tissue damage in alloxan induced diabetic rats.

PubMed

Bhattacharya, Semantee; Gachhui, Ratan; Sil, Parames C

2013-10-01

Diabetic complications associated with increased oxidative stress can be suppressed by antioxidants. In the present study we investigated the antidiabetic and antioxidant effects of Kombucha (KT), a fermented black tea, in comparison to that of unfermented black tea (BT), in ALX-induced diabetic rats. ALX exposure lowered the body weight and plasma insulin by about 28.12% and 61.34% respectively and elevated blood glucose level and glycated Hb by about 3.79 and 3.73 folds respectively. The oxidative stress related parameters like lipid peroxidation end products (increased by 3.38, 1.7, 1.65, 1.94 folds respectively), protein carbonyl content (increased by 2.5, 2.35, 1.8, 3.26 folds respectively), glutathione content (decreased by 59.8%, 47.27%, 53.69%, 74.03% respectively), antioxidant enzyme activities were also altered in the pancreatic, hepatic, renal and cardiac tissues of diabetic animals. Results showed significant antidiabetic potential of the fermented beverage (150 mg lyophilized extract/kg bw for 14 days) as it effectively restored ALX-induced pathophysiological changes. Moreover, it could ameliorate DNA fragmentation and caspase-3 activation in the pancreatic tissue of diabetic rats. Although unfermented black tea is effective in the above pathophysiology, KT was found to be more efficient. This might be due to the formation of some antioxidant molecules during fermentation period. Copyright © 2013 Elsevier Ltd. All rights reserved.

Antidepressive-like effects and antioxidant activity of green tea and GABA green tea in a mouse model of post-stroke depression.

PubMed

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.

Contamination of Tea and Tea Infusion with Polycyclic Aromatic Hydrocarbons

PubMed Central

Zachara, Alicja; Gałkowska, Dorota; Juszczak, Lesław

2017-01-01

The aim of this work was to validate the method of determination of polycyclic aromatic hydrocarbons (PAHs), i.e., benzo(a)pyrene and sum of benzo(a)pyrene, benz(a)anthracene, benzo(b)fluoranthene and chrysene in different types of tea, as well as to assess the transfer of these contaminants from tea to tea infusion. The research materials were popular types of black, green, red and white tea. Quantitative and qualitative determination of PAHs was performed by High Performance Liquid Chromatography with fluorimetric detection (HPLC-FLD). The samples were prepared by QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) technique followed by cleaning-up by dispersion solid-phase extraction (d-SPE). Values of limit of detection and limit of quantification obtained in the validation of the method were lower than the respective maximum values given in Commission Regulation (EU) No. 836/2011. The level of contamination of popular teas commercially available on the Polish market with PAHs is similar to that of teas available in other countries, with a very large variation in the concentration of each of the compounds. The highest benzo(a)pyrene and Σ4PAHs contents (209 ± 42 μg/kg and 756 ± 151 μg/kg, respectively) were found for black tea leaves. The transfer of Σ4PAHs from black tea to tea infusions was 0.48%, while it was 1.55–1.72% for red, white and green teas. PMID:29283369

Potent suppressing activity of the non-polyphenolic fraction of green tea (Camellia sinensis) against genotoxin-induced umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002)--association with pheophytins a and b.

PubMed

Okai, Y; Higashi-Okai, K

1997-11-25

Antigenotoxic and antimutagenic activities of green tea extract and tea-derived polyphenols have been studied using in vitro and in vivo experiments. However, antigenotoxic substances in the non-polyphenolic fraction of green tea have been poorly elucidated. In the present study, the effect of the non-polyphenolic fraction of green tea on genotoxin-induced umu C gene expression was analyzed using a tester bacteria, and potent antigenotoxic substances in the non-polyphenolic fraction were identified. The non-polyphenolic fraction of green tea showed strong suppressive activities against umu C gene expression in Salmonella typhimurium (TA 1535/pSK 1002) induced by 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indol (Trp-P-1) or mitomycin C (MMC) in the presence or absence of S9 metabolizing enzyme mixture. The non-polyphenolic fraction of green tea exhibited major two-color bands in a silica gel TLC and they were identified as chlorophyll-related compounds, pheophytins a and b, judged by their specific colors, Rf values in silica gel TLC and absorption spectra. These pigments showed significant suppressive activities against umu C gene expression in tester bacteria induced by Trp-P- and MMC in a dose-dependent manner. These results suggest that the non-polyphenolic fraction of green tea contains pheophytins a and b as potent antigenotoxic substances.

Influence of the interactions between tea (Camellia sinensis) extracts and ascorbic acid on their antioxidant activity: analysis with interaction indexes and isobolograms.

PubMed

Enko, Jolanta; Gliszczyńska-Świgło, Anna

2015-01-01

Products containing natural additives, including antioxidants, are usually perceived by consumers as safer than those with synthetic ones. Natural antioxidants, besides having a preservative activity, may exert beneficial health effects. Interactions between antioxidants may significantly change their antioxidant activity, thus in designing functional foods or food/cosmetic ingredients knowledge about the type of interactions could be useful. In the present study, the interactions between ascorbic acid (AA; vitamin C) and different black and green tea extracts and the influence on their antioxidant activities were investigated. The antioxidant activities of tea extracts and their mixtures with AA prepared in several different weight ratios were measured using the trolox equivalent antioxidant capacity (TEAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and ferric-reducing antioxidant power (FRAP) methods. The type of interaction was determined by interaction indexes and isobolograms. It was found that the weight ratio of extracts to AA significantly influenced the antioxidant activity of a mixture and the type of interaction between these components. The weight ratio of tea extract to AA can cause the change of interaction, e.g. from antagonism to additivism or from additivism to synergism. The observed differences in the type of interactions were probably also a result of different extracts' polyphenol composition and content. The type of interaction may also be affected by the medium in which extracts and AA interact, especially its pH and the solvent used. To obtain the best antioxidant effect, all these factors should be taken into account during the design of a tea extract-AA mixture.

Effects of oolong tea on plasma antioxidative capacity in mice loaded with restraint stress assessed using the oxygen radical absorbance capacity (ORAC) assay.

PubMed

Kurihara, Hiroshi; Fukami, Harukazu; Asami, Sumio; Toyoda, Yoshiko; Nakai, Masaaki; Shibata, Hiroshi; Yao, Xin-Sheng

2004-07-01

In the present study, we investigated the antioxidative effect of oolong tea in vitro and in vivo using the oxygen radical absorbance capacity (ORAC) assay. An oolong tea extract, catechin and related compounds suppressed the oxidation of fluorescence induced by AAPH in a dose-dependent manner, that is, they prolonged the antioxidant time in vitro. Oral administration of the oolong tea extract to mice treated with restraint stress increased ORAC activity in plasma as compared with a stress control group. The extract also increased plasma vitamin C levels, and there was a good relationship between ORAC activity and the vitamin C level in plasma. The elevation of plasma ORAC and vitamin C level may have been related to the stress-relieving effect of oolong tea. These effects are probably due to the antioxidative properties of the tea. Thus, these findings suggested that oolong tea has beneficial effects on health related to its antioxidative action.

Role of catechins in the antioxidant capacity of an active film containing green tea, green coffee, and grapefruit extracts.

PubMed

Colon, M; Nerin, C

2012-10-03

The oxygen radical absorbance capacity (ORAC) method was used to characterize the antioxidant capacity of natural extracts of green tea, green coffee, and grapefruit. These natural extracts were incorporated into a plastic film layer, which was subsequently subjected to a free radical gas stream in order to determine the antioxidant capacity directly in the active film. The green tea extract (GTE) afforded the strongest antioxidant activity. To identify the active compounds in the extract, concentration of the diverse catechins in samples were determined by HPLC-UV analysis. The results showed that the content of catechins in the GTE is around 77% (w/w), the major components being (-)-epigallocatechin gallate, (-)-epicatechin gallate, and (-)-epicatechin. A variation in the concentration profile of catechins was detected during the oxidation process. The chromatographic study demonstrated that (-)-gallocatechin, (-)- epigallocatechin, (+)-catechin, and (-)-catechin gallate exhibited the most radical scavenging.

Quality components and antidepressant-like effects of GABA green tea.

PubMed

Teng, Jie; Zhou, Wen; Zeng, Zhen; Zhao, Wenfang; Huang, Yahui; Zhang, Xu

2017-09-20

Gamma (γ)-aminobutyric acid (GABA) green tea, with high GABA content, is a kind of special green tea. The goals of this study are to analyze the changes in quality components of green tea during anaerobic treatment, and to investigate whether or not the extract of GABA present in green tea can prevent depression or improve the depressive state of animals. Results showed that GABA content in green tea had increased significantly after anaerobic treatment. The contents of tea polysaccharides, total free amino acids, and water extracts were also increased whereas tea polyphenols were reduced. More importantly, the extract of GABA green tea could alleviate mouse depression and stress from desperate environments through the forced swim test (FST), tail suspension test (TST), mRNA and protein expression levels of GABA A receptors. Therefore, these results indicate that GABA green tea may have a health effect on prevention and alleviation of depression, and it works on the GABAergic neurotransmission of mouse cerebral cortex via up-regulating expression of the GABA A receptor α1 subunit, thus ameliorating depression.

GREEN SYNTHESIS OF SILVER AND PALLADIUM NANOPARTICLES AT ROOM TEMPERATURE USING COFFEE AND TEA EXTRACT

EPA Science Inventory

An extremely simple green approach that generates bulk quantities of nanocrystals of noble metals such as silver (Ag) and palladium (Pd) using coffee and tea extract at room temperature is described. The single-pot method uses no surfactant, capping agent, and/or template. The ob...

Green Tea Catechin Consumption Enhances Exercise-Induced Abdominal Fat Loss

USDA-ARS?s Scientific Manuscript database

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...

Toxic and essential mineral elements content of black tea leaves and their tea infusions consumed in Iran.

PubMed

Salahinejad, Maryam; Aflaki, Fereydoon

2010-04-01

The metal contents of eleven black tea samples, four cultivated in Iran and seven imported, and their tea infusions were determined. Twelve elements consisting toxic metals (Al, As, Pb, Cr, Cd, and Ni) and essential mineral elements (Fe, Zn, Cu, Mn, Ca, and Mg) were analyzed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, Ca, Mg, and Mn ranged in black tea leaves at mg g(-1) levels, while Cr, Fe, Ni, Cu, Zn were at microg g(-1) levels. Analysis of variance showed no statistically significant differences among most elements determined in cultivated and imported black teas in Iran except for Ni and Cu. The extraction efficiency of each element into tea infusions was evaluated. The solubility of measured metals in infusion extracts varied widely and ranged from 0 to 59.3%. Among the studied elements, Cr, Pb, and Cd showed the lowest rates of solubility and Ni had the highest rates of solubility. The amount of toxic metals and essential mineral elements that one may take up through consumption of black tea infusion was estimated. The amount of realizing each element into tea infusions and acceptable daily intake, for safety consumption of black tea, was compared.

Effect of Kombucha tea on chromate(VI)-induced oxidative stress in albino rats.

PubMed

Sai Ram, M; Anju, B; Pauline, T; Dipti, P; Kain, A K; Mongia, S S; Sharma, S K; Singh, B; Singh, R; Ilavazhagan, G; Kumar, D; Selvamurthy, W

2000-07-01

The effect of Kombucha tea (KT) on oxidative stress induced changes in rats subjected to chromate treatment are reported. KT feeding alone did not show any significant change in malondialdehyde (MDA) and reduced glutathione (GSH) levels, but did enhance humoral response and delayed type of hypersensitivity (DTH) response appreciably over control animals. Chromate treatment significantly enhanced plasma and tissue MDA levels, decreased DTH response considerably, enhanced glutathione peroxidase and catalase activities; however, no change in GSH, superoxide dismutase and antibody titres was noticed. KT feeding completely reversed the chromate-induced changes. These results show that Kombucha tea has potent anti-oxidant and immunopotentiating activities.

Effect of borage and green tea aqueous extracts on the quality of lamb leg chops displayed under retail conditions.

PubMed

Bellés, M; Alonso, V; Roncalés, P; Beltrán, J A

2017-07-01

Different concentrations of two aqueous extracts from green tea leaves and borage seeds with potential antioxidant activity were evaluated in lamb leg chops. Chops were sprayed with 0.005, 0.05, 0.5, 5% (p/v) green tea extracts (T) and 0.5, 5 and 10% (p/v) borage seed extracts (B) and displayed under retail conditions for 13days. Total polyphenols, TBARS, colour, microbial and sensory analyses were performed. The extracts showed a concentration-dependent action; the minimum concentration of polyphenols which significantly reduced lipid oxidation was 2.08mgGAE/100cm 2 of meat. Both 0.5% T and 10% B limited colour deterioration, reducing also metmyoglobin formation. The extracts showed no antimicrobial effect, exceeding microbial counts of 7logCFU/cm 2 at 13days of display. Sensory analyses determined that none of the extracts added herb odours or flavours to lamb. In conclusion, 0.5% T or 10% B extracts extended lamb shelf life from 8 to 11days, so both would be recommended for lamb chops preservation. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

PubMed

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.

Influence of the addition and storage time of crude extract of tea leaves (camellia sinensis l.) toward value of free fatty acid in crude palm oil

NASA Astrophysics Data System (ADS)

Erwin; Wahifiyah, E.; Hairani, R.; Panggabean, A. S.

2018-04-01

The purpose of this study was to determine the effect of the crude extract of tea leaves (Camellia sinensis L.) and storage time on the content of free fatty acid in palm oil. The dried tea leaves were macerated and concentrated by rotary evaporator. The extract obtained was added to crude palm oil with various added mass of the extract and various storage times. Phytochemical tests indicated the presence of secondary metabolites including alkaloids, triterpenoids, steroids, phenolics and flavonoids. The ANOVA test showed a decrease in free fatty acid content in crude palm oil with the addition of tea leaves extract. The LSD (Least Significant Difference) test showed the best influence on ALB of palm oil is on the total extract mass of 2 grams and the storage time of 20 days.

The Spectral Emission Characteristics of Laser Induced Plasma on Tea Samples

NASA Astrophysics Data System (ADS)

Zheng, Peichao; Shi, Minjie; Wang, Jinmei; Liu, Hongdi

2015-08-01

Laser induced breakdown spectroscopy (LIBS) provides a useful technique for food security as well as determining nutrition contents. In this paper, optical emission studies of laser induced plasma on commercial tea samples were carried out. The spectral intensities of Mg, Mn, Ca, Al, C and CN vibration bands varying with laser energy and the detection delay time of an intensified charge coupled device were studied. In addition, the relative concentrations of six microelements, i.e., Mg, Mn, Ca, Al, Na and K, were analyzed semi-quantitatively as well as H, for four kinds of tea samples. Moreover, the plasma parameters were explored, including electron temperature and electron number density. The electron temperature and electron number density were around 11000 K and 1017 cm-3, respectively. The results show that it is reasonable to consider the LIBS technique as a new method for analyzing the compositions of tea leaf samples. supported by National Natural Science Foundation of China (No. 61205149), the Scientific and Technological Talents Training Project of Chongqing, China (No. CSTC2013kjrc-qnrc40002), the Scientific and Technological Project of Nan'an District (2011) and the Visiting Scholarship of State Key Laboratory of Power Transmission Equipment & System Security and New Technology at Chongqing University, China (No. 2007DA10512714409)

Extraction Efficiency of Different Solvents and LC-UV Determination of Biogenic Amines in Tea Leaves and Infusions

PubMed Central

Spizzirri, U. Gianfranco; Picci, Nevio

2016-01-01

Biogenic amines (BAs), that is, spermine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine, cadaverine, and serotonin, have been determined in several samples of tea leaves, tea infusions, and tea drinks by LC-UV method after derivatization with dansyl chloride. Different extraction solvents have been tested and TCA 5% showed better analytical performances in terms of linearity, recovery percentages, LOD, LOQ, and repeatability than HCl 0.1 M and HClO4 0.1 M and was finally exploited for the quantitative determination of BAs in all samples. In tea leaves total BAs concentration ranged from 2.23 μg g−1 to 11.24 μg g−1 and PUT (1.05–2.25 μg g−1) and SPD (1.01–1.95 μg g−1) were always present, while SER (nd–1.56 μg g−1), HIS (nd–2.44 μg g−1), and SPM (nd–1.64 μg g−1) were detected more rarely. CAD and PHE were determined in few samples at much lower concentrations while none of the samples contained TYR. Tea infusions showed the same trend with total BAs concentrations never exceeding 80.7 μg L−1. Black teas showed higher amounts of BAs than green teas and organic and decaffeinated samples always contained much lower BAs levels than their conventional counterparts. PMID:27555979

Green synthesis of tea Ag nanocomposite hydrogels via mint leaf extraction for effective antibacterial activity.

PubMed

Jayaramudu, Tippabattini; Varaprasad, Kokkarachedu; Raghavendra, Gownolla Malegowd; Sadiku, E R; Mohana Raju, Konduru; Amalraj, John

2017-10-01

In this report, we investigated the swelling behavior and antibacterial property of nanosilver composite hydrogels made from tea with polyacrylamide via a free-radical polymerization and green process technique. This is probably for the first time; tea-based nano silver composite hydrogels were developed. The composite hydrogels comprise embedded nano silver particles in the tea hydrogel matrix via a green process with mint leaf extract. The size of the nano silver particles in the hydrogel matrix was found to be < 10 nm. The nano silver composite hydrogels formed and their blank hydrogels from the mint leaf were characterized by using ultraviolet-visible spectroscopy, scanning electron microscopy with energy dispersive spectroscopy, transmission electron microscopy, thermogravimetric analysis and X-ray diffraction studies. The nano silver composite hydrogels developed exhibit eminent antibacterial activity against Escherichia coli and Staphylococcus aureus. This clearly indicates that the nano silver composite hydrogels are potential candidates for antimicrobial applications.

Structural characterization and evaluation of the antioxidant activities of polysaccharides extracted from Qingzhuan brick tea.

PubMed

Yang, Xinhe; Huang, Mingjun; Qin, Caiqin; Lv, Bangyu; Mao, Qingli; Liu, Zhonghua

2017-08-01

The crude tea polysaccharides (CTPS) from Qingzhuan brick tea(QZBT) were extracted and fractionated to afford two fractions, namely TPS-1 and TPS-2. Analyses were conducted concerning the structural characterization and antioxidant activities of these samples. Component analysis revealed that the carbohydrate, uronic acid, protein and polyphenol contents of these samples differed significantly. Fourier transform infrared analysis showed that these samples showed similar characteristic absorption peaks for polysaccharides. Ultraviolet-visible spectroscopy, circular dichroism, scanning electron microscopy and thermogravimetric analyses indicated that there were considerable differences in the presence of protein, surface features, conformational characteristics and thermodynamic behaviors. For antioxidant activities in vitro, CTPS, TPS-1 and TPS-2 exhibited concentration-dependent antioxidant activities, with TPS-2 showing significantly higher antioxidant activity than CTPS and TPS-1. These results provide a scientific and strong foundation for the use of tea polysaccharides(TPS) from QZBT and further research towards the relationships between the characteristics and antioxidant activities of TPS. Copyright © 2017 Elsevier B.V. All rights reserved.

Character impact odorants of fennel fruits and fennel tea.

PubMed

Zeller, Annette; Rychlik, Michael

2006-05-17

The flavor of fennel fruits and fennel tea was examined by aroma extract dilution analysis of the respective dichloromethane extracts. In both fennel fruits and tea, trans-anethole, anisaldehyde, and trans-4,5-epoxy-2(E)-decenal showed high flavor dilution (FD) factors followed by fenchone, 1,8-cineole, (R)-alpha-pinene, estragole, and beta-myrcene. On the basis of these results, the odorants showing higher FD factors were quantified in tea as well as in fruits, and odor activity values (OAV) in tea were calculated by dividing the concentration of the compound by its recognition threshold in water. The highest OAV was found for trans-anethole, followed by estragole, fenchone, 1,8-cineole, (R)-alpha-pinene, beta-myrcene, and anisaldehyde. From a comparison of the concentrations of odorants in fruits and tea, trans-anethole and estragole showed similar extraction rates of approximately 10-15%, whereas the extraction rates for (R)-alpha-pinene, beta-myrcene, and limonene were below 2%. In contrast to this, fenchone, camphor, linalool, and carvone showed higher extraction rates (26-50%), whereas the high apparent extraction rates of anisalcohol (393%) and vanilline (480%) were attributed to the formation from precursors. Sensory studies of aqueous models containing odorants in the amounts quantified in fennel teas revealed high similarity of the models with the tea and proved that all impact odorants had been identified in their correct concentrations. Further sensory experiments showed that estragole had no odor impact on the overall flavor of fennel tea, and, therefore, a reduction of estragole in fennel products would have no negative impact on their sensoric quality. In contrast to this, trans-anethole and fenchone were found to be character impact compounds of fennel.

Application of enzymes in the production of RTD black tea beverages: a review.

PubMed

Kumar, Chandini S; Subramanian, R; Rao, L Jaganmohan

2013-01-01

Ready-to-drink (RTD) tea is a popular beverage in many countries. Instability due to development of haze and formation of tea cream is the common problem faced in the production of RTD black tea beverages. Thus decreaming is an important step in the process to meet the cold stability requirements of the product. Enzymatic decreaming approaches overcome some of the disadvantages associated with other conventional decreaming methods such as cold water extraction, chill decreaming, chemical stabilization, and chemical solubilization. Enzyme treatments have been attempted at three stages of black tea processing, namely, enzymatic treatment to green tea and conversion to black tea, enzymatic treatment to black tea followed by extraction, and enzymatic clarification of extract. Tannase is the most commonly employed enzyme (tannin acyl hydrolase EC 3.1.1.20) aiming at improving cold water extractability/solubility and decreasing tea cream formation as well as improving the clarity. The major enzymatic methods proposed for processing black tea having a direct or indirect bearing on RTD tea production, have been discussed along with their relative advantages and limitations.

Effect of delta-tocotrienols and green tea polyphenols on high-fat-diet-induced bone deterioration in male C57BL/6J mice

USDA-ARS?s Scientific Manuscript database

Our previous studies demonstrated an osteo-protective roles for tocotrienols (TT, extracted from annatto consisting of 90% delta-TT and 10% gamma TT) and green tea polyphenols (GTP, extracted from green tea) in obese animals. This study further examined the combined effects of TT with GTP on high-fa...

9,10-Anthraquinone deposit in tea plantation might be one of the reasons for contamination in tea.

PubMed

Wang, Xuan; Zhou, Li; Luo, Fengjian; Zhang, Xinzhong; Sun, Hezhi; Yang, Mei; Lou, Zhengyun; Chen, Zongmao

2018-04-01

9,10-Anthraquinone (AQ) was a new contaminant, with unknown sources, occurred globally in tea. European Union (EU) fixed the maximum residue limit (MRL) of 0.02mg/kg. The pollution source of AQ in tea was traced from the view of AQ deposit on tea crop by simulation. The possible contamination pathway and main factors to decrease AQ were explored in tea cultivation- tea manufacture- tea infusion, on the basis of AQ analytical methods by using solvent extraction and gas chromatography-tandem mass spectrometry (GC-MS/MS) quantification. 58.8-84.6% of AQ degraded in tea processing, and drying played a key role to reduce the AQ contamination. Certain concentration of AQ deposited on tea shoots could resulted in AQ beyond the MRL of 0.02mg/kg in tea. AQ leaching into tea brew (about 10%) could lead to the possible health risk. AQ deposit on tea crop during the tea cultivation might cause the AQ contamination in tea. Copyright © 2017. Published by Elsevier Ltd.

Comparison of the Level of Boron Concentrations in Black Teas with Fruit Teas Available on the Polish Market

PubMed Central

Zioła-Frankowska, Anetta; Frankowski, Marcin; Novotny, Karel; Kanicky, Viktor

2014-01-01

The determination of boron by inductively coupled plasma-atomic emission spectrometry has been carried in water-soluble and acid soluble (total content) fractions of 36 samples of traditional black tea and fruit brew. The estimation of the impact of the type of tea on the concentration of boron in water-soluble and acid extracts and potential human health risk from the daily intake of boron was carried out in this study. The levels of boron differed significantly in black and fruit tea types. The mean total content of boron ranged from 8.31 to 18.40 mg/kg in black teas, from 12.85 to 15.13 mg/kg in black tea with fruit flavor, and from 12.09 to 22.77 mg/kg in fruit brews. The degree of extraction of boron in black tea ranged from 8% to 27% and for fruit tea from 17% to 69%. In addition, the values below 25% were of black teas with fruit flavors. The daily intake of B from tea infusions (three cups/day) is still within the average daily intake except for some of the fruit brews which exceed acceptable regulations of the daily intake of total boron by humans. Hence, it may not produce any health risks for human consumption, if other sources of metal contaminated food are not taken at the same time. PMID:25379551

Comparison of the level of boron concentrations in black teas with fruit teas available on the Polish market.

PubMed

Zioła-Frankowska, Anetta; Frankowski, Marcin; Novotny, Karel; Kanicky, Viktor

2014-01-01

The determination of boron by inductively coupled plasma-atomic emission spectrometry has been carried in water-soluble and acid soluble (total content) fractions of 36 samples of traditional black tea and fruit brew. The estimation of the impact of the type of tea on the concentration of boron in water-soluble and acid extracts and potential human health risk from the daily intake of boron was carried out in this study. The levels of boron differed significantly in black and fruit tea types. The mean total content of boron ranged from 8.31 to 18.40 mg/kg in black teas, from 12.85 to 15.13 mg/kg in black tea with fruit flavor, and from 12.09 to 22.77 mg/kg in fruit brews. The degree of extraction of boron in black tea ranged from 8% to 27% and for fruit tea from 17% to 69%. In addition, the values below 25% were of black teas with fruit flavors. The daily intake of B from tea infusions (three cups/day) is still within the average daily intake except for some of the fruit brews which exceed acceptable regulations of the daily intake of total boron by humans. Hence, it may not produce any health risks for human consumption, if other sources of metal contaminated food are not taken at the same time.

GENO PROTECTIVE AND ANTI-APOPTOTIC EFFECT OF GREEN TEA AGAINST PERINATAL LIPOPOLYSACCHARIDE-EXPOSURE INDUCED LIVER TOXICITY IN RAT NEWBORNS

PubMed Central

Allam, Ahmed A.; Gabr, Sami A.; Ajarem, Jamaan; Alghadir, Ahmad H.; Sekar, Revathi; Chow, Billy KC

2017-01-01

Background: This study aims to examine the protective effect of green tea on the disturbances in oxidative stress and apoptosis related factors, mostly produced due to perinatal lipopolysaccharide (LPS) exposure, that subsequently induces liver cell damage. Materials and Methods: Anti-free radical, Antioxidant, scavenging, geno-protective, and antiapoptotic activity of aqueous green tea extract (AGTE) were assessed against LPS-induced hepatic dysfunction in newborn-rats. AGTE at doses of 100 & 200 mg/kg was orally administered daily to rat dams, during gestation and lactation. Results: AGTE was observed to exhibit protective effects by significantly attenuating LPS-induced alterations in serum AST, ALT, bilirubin, and albumin levels. Significant increase in the total antioxidant capacity (TAC), DNA contents, and reduction in nitric oxide (NO) levels were observed in AGTE treated rats comparing LPS-toxicated ones. Additionally, AGTE treatment significantly down-regulated apoptotic markers and this effect was directly correlated to the degree of hepatic fibrosis. The possible mechanisms of the potential therapeutic-liver protective effect of AGTE could be due to free radical scavenging potential and antiapoptotic properties caused by the presence of antioxidant polyphenolic components in AGTE. Conclusion: We thereby propose, based on our findings, that the anti-free radical and anti-apoptotic inducing properties of AGTE active constituents attribute to its functional efficacy as anti-fibrotic agent. PMID:28573233

The antioxidant property of chitosan green tea polyphenols complex induces transglutaminase activation in wound healing.

PubMed

Qin, Yao; Guo, Xing Wei; Li, Lei; Wang, Hong Wei; Kim, Wook

2013-06-01

The present study examined, for the first time, the in vitro wound healing potential of chitosan green tea polyphenols (CGP) complex based on the activation of transglutaminase (TGM) genes in epidermal morphogenesis. Response surface methodology was applied to determine the optimal processing condition that gave maximum extraction of green tea polyphenols. The antioxidant activity, scavenging ability, and chelating ability were studied and expressed as average EC50 values of CGP and other treatments. In silico analysis and gene coexpression network was subjected to the TGM sequences analysis. The temporal expressions of TGMs were profiled by semi-quantitative reverse transcription (RT)-PCR technology within 10 days after wounding and 2 days postwounding. CGP showed the effectiveness of antioxidant properties, and the observations of histopathological photography showed advanced tissue granulation and epithelialization formation by CGP treatment. In silico and coexpression analysis confirmed the regulation via TGM gene family in dermatological tissues. RT-PCR demonstrated increased levels of TGM1-3 expression induced by CGP treatment. The efficacy of CGP in wound healing based on these results may be ascribed to its antioxidant properties and activation of the expression of TGMs, and is, thus, essential for the facilitated repair of skin injury.

[Preparation and component analysis of tea pigments].

PubMed

Li, Daxiang; Wan, Xiaochun; Xia, Tao

2004-11-01

To prepare tea pigments. Tea pigments are prepared by solvent extraction from Sri lanka black tea. Tea pigments contains the components as follows: caffeine 1.77%, epigallocatechin 1.37%, catechin 1.20%, epicatechin 9.55%, epigallocatechin gallate 10.52%, epicatechin gallate 9.94%, theaflavin 10.34%, theaflavin monogallate 9.57%, theaflavin digallate 4.81%, thearubigin about 40.93%. The best proportions of the compound that are obtained with HPLC analysis.

Optimization of the Preparation Conditions of Yerba Mate tea Beverage to Maximize Chlorogenic Acids Extraction.

PubMed

da Silveira, Tayse Ferreira Ferreira; Meinhart, Adriana Dillenburg; de Souza, Thaís Cristina Lima; Cunha, Elenice Carla Emídio; de Moraes, Maria Rosa; Filho, José Teixeira; Godoy, Helena Teixeira

2017-06-01

The beverage obtained from the yerba mate tea, besides being the most consumed in Brazil, has high concentrations of chlorogenic acids. In this study, a central composite design was employed to establish the best infusion time, temperature and water volume to maximize the extraction of chlorogenic acids 5-caffeoylquinic (5CQ), 3.4-dicaffeoylquinic (3.4 DQ), 3.5-dicaffeoylquinic (3.5 DQ) and 4.5-dicaffeoylquinic (4.5 DQ), from the leaves and stems of yerba mate tea (beverage ready for consumption). Analyses were performed by high-performance liquid chromatography and the optimum conditions were obtained through the use of the desirability function of Derringer and Suich. The maximum chlorogenic acids content in the beverage was obtained when the infusion was prepared with 2 g of mate tea, in 300 mL of water at 95 °C, under infusion for 16 min. The optimal conditions were applied for the preparation of beverages from 15 commercial samples of yerba mate tea, and it was observed that the sum of the concentration of the four compounds showed variation of up to 79 times between the average of the samples, which can be attributed to climatic conditions of cultivation of the plant and/or of processing.

Volatile aroma compounds in various brewed green teas.

PubMed

Lee, Jeehyun; Chambers, Delores H; Chambers, Edgar; Adhikari, Koushik; Yoon, Youngmo

2013-08-20

This study identifies and semi-quantifies aroma volatiles in brewed green tea samples. The objectives of this study were to identify using a gas chromatograph-mass spectrometer (GC-MS) paired with a headspace solid-phase micro-extraction (HS-SPME) the common volatile compounds that may be responsible for aroma/flavor of the brewed liquor of a range of green tea samples from various countries as consumed and to determine if green teas from the same region have similarities in volatile composition when green tea samples are prepared for consumption. Twenty-four green tea samples from eight different countries were brewed as recommended for consumer brewing. The aroma volatiles were extracted by HS-SPME, separated on a gas chromatograph and identified using a mass spectrometer. Thirty-eight compounds were identified and the concentrations were semi-quantified. The concentrations were lower than those reported by other researchers, probably because this research examined headspace volatiles from brewed tea rather than solvent extraction of leaves. No relationship to country of origin was found, which indicates that other factors have a greater influence than country of origin on aroma.

Chapter 8. Tea and Cancer Prevention: Epidemiological Studies

PubMed Central

Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M.

2011-01-01

Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiologic studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans. PMID:21419224

Green tea extracts for the prevention of metachronous colorectal adenomas: a pilot study.

PubMed

Shimizu, Masahito; Fukutomi, Yasushi; Ninomiya, Mitsuo; Nagura, Kazuo; Kato, Tomohiro; Araki, Hiroshi; Suganuma, Masami; Fujiki, Hirota; Moriwaki, Hisataka

2008-11-01

Experimental studies indicate the chemopreventive properties of green tea extract (GTE) on colorectal cancer. Epidemiologically, green tea consumption of > 10 cups daily reduced colorectal cancer risk in Japanese. Because colorectal adenomas are the precursors to most sporadic colorectal cancers, we conducted a randomized trial to determine the preventive effect of GTE supplements on metachronous colorectal adenomas by raising green tea consumption in the target population from an average of 6 cups (1.5 g GTE) daily to > or = 10 cups equivalent (2.5 g GTE) by supplemental GTE tablets. We recruited 136 patients, removed their colorectal adenomas by endoscopic polypectomy, and 1 year later confirmed the clean colon (i.e., no polyp) at the second colonoscopy. The patients were then randomized into two groups while maintaining their lifestyle on green tea drinking: 71 patients supplemented with 1.5 g GTE per day for 12 months and 65 control patients without supplementation. Follow-up colonoscopy was conducted 12 months later in 125 patients (65 in the control group and 60 in the GTE group). The incidence of metachronous adenomas at the end-point colonoscopy was 31% (20 of 65) in the control group and 15% (9 of 60) in the GTE group (relative risk, 0.49; 95% confidence interval, 0.24-0.99; P < 0.05). The size of relapsed adenomas was also smaller in the GTE group than in the control group (P < 0.001). No serious adverse events occurred in the GTE group. GTE is an effective supplement for the chemoprevention of metachronous colorectal adenomas.

[Determination of catechins and caffeine in tea and tea beverages by high-performance liquid chromatography].

PubMed

Ling, Yun; Zhao, Yun-feng; Li, Zhi-jun; Zhang, Gong; Wu, Yongning

2005-03-01

A high-performance liquid chromatography method was developed for the determination of total tea catechin and caffeine. The catechins needed to be determined are: (-)-catechin, (-)-epigallocatechin, (-)-epigallocatechin gallate, (-)-epicatechin, (-)-epicatechin gallate, (-)-gallocatechin, (-)-gallocatechin gallate, (-)-catechin gallate and caffeine. The catechins in the tea was extracted with water:ethanol (3:7) by sonication for 20 min. After the extraction solution was centrifuged, it was analyzed by HPLC. The column used was a CAPCELL PAK C18 MG (4.6mm I.D. x 150mm) and gradient elution at constant column temperature with 30 degrees C under UV detector with 210nm. Mobile phase A was 0.1% H3PO4 in water, mobile phase B was 0.1% H3PO4 in methanol with the flow rate 1ml/min. The results showed that the concentration of the catechins and caffeine and their peak areas achieved good linear relation, r > 0.999. The recoveries were between 61.7%-117.3%. RSD was below 10%. With this method, some tea samples were determined, the results were favorable. The method can be applied for determination of catechin and caffeine in tea and tea beverages.

Antioxidative activity of green tea treated with radical initiator 2, 2'-azobis(2-amidinopropane) dihydrochloride.

PubMed

Yokozawa, T; Cho, E J; Hara, Y; Kitani, K

2000-10-01

This study investigated the antioxidative activity of green tea extract, and a green tea tannin mixture and its components, under conditions of radical generation using the hydrophilic azo compound, 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) to generate peroxyl radicals at a constant and measurable rate in the cultured renal epithelial cell line, LLC-PK(1), which is susceptible to oxidative damage. Treatment with AAPH decreased cell viability and increased the formation of thiobarbituric acid-reactive substances. However, green tea extract, and the tannin mixture and its components, comprising (-)-epigallocatechin 3-O-gallate (EGCg), (-)-gallocatechin 3-O-gallate (GCg), (-)-epicatechin 3-O-gallate (ECg), (-)-epigallocatechin (EGC), (+)-gallocatechin (GC), (-)-epicatechin (EC), and (+)-catechin (C), showed protective activity against AAPH-induced cellular damage. The tannin mixture and its components exhibited higher antioxidative activity than the green tea extract. Furthermore, EGCg and GCg had higher activity than EGC and GC, respectively. In particular, EGCg exerted the most significant cellular protective activity against AAPH. These results indicate that green tea tannin may inhibit cellular loss and lipid peroxidation resulting from the peroxyl radical generated by AAPH, and that the chemical structure of tannin is also involved in the activity, suggesting that the O-dihydroxy structure in the B ring and the galloyl groups are important determinants for radical scavenging and antioxidative potential.

Green tea extract decreases starch digestion and absorption from a test meal in humans: a randomized, placebo-controlled crossover study.

PubMed

Lochocka, Klaudia; Bajerska, Joanna; Glapa, Aleksandra; Fidler-Witon, Ewa; Nowak, Jan K; Szczapa, Tomasz; Grebowiec, Philip; Lisowska, Aleksandra; Walkowiak, Jaroslaw

2015-07-30

Green tea is known worldwide for its beneficial effects on human health. However, objective data evaluating this influence in humans is scarce. The aim of the study was to assess the impact of green tea extract (GTE) on starch digestion and absorption. The study comprised of 28 healthy volunteers, aged 19 to 28 years. In all subjects, a starch (13)C breath test was performed twice. Subjects randomly ingested naturally (13)C-abundant cornflakes during the GTE test (GTE 4 g) or placebo test. The cumulative percentage dose recovery (CPDR) was significantly lower for the GTE test than for the placebo test (median [interquartile range]: 11.4% [5.5-15.5] vs. 16.1% [12.7-19.5]; p = 0.003). Likewise, CPDR expressed per hour was considerably lower in each point of the measurement. In conclusion, a single dose of green tea extract taken with a test meal decreases starch digestion and absorption.

Three-dimensional modeling of tea-shoots using images and models.

PubMed

Wang, Jian; Zeng, Xianyin; Liu, Jianbing

2011-01-01

In this paper, a method for three-dimensional modeling of tea-shoots with images and calculation models is introduced. The process is as follows: the tea shoots are photographed with a camera, color space conversion is conducted, using an improved algorithm that is based on color and regional growth to divide the tea shoots in the images, and the edges of the tea shoots extracted with the help of edge detection; after that, using the divided tea-shoot images, the three-dimensional coordinates of the tea shoots are worked out and the feature parameters extracted, matching and calculation conducted according to the model database, and finally the three-dimensional modeling of tea-shoots is completed. According to the experimental results, this method can avoid a lot of calculations and has better visual effects and, moreover, performs better in recovering the three-dimensional information of the tea shoots, thereby providing a new method for monitoring the growth of and non-destructive testing of tea shoots.

Evaluation of antioxidant activity of chrysanthemum extracts and tea beverages by gold nanoparticles-based assay.

PubMed

Liu, Quanjun; Liu, Haifang; Yuan, Zhiliang; Wei, Dongwei; Ye, Yongzhong

2012-04-01

A gold nanoparticles-based (GNPs-based) assay was developed for evaluating antioxidant activity of chrysanthemum extracts and tea beverages. Briefly, a GNPs growth system consisted of designated concentrations of hydrogen tetrachloroaurate, cetyltrimethyl ammonium bromide, sodium citrate, and phosphate buffer was designed, followed by the addition of 1 mL different level of test samples. After a 10-min reaction at 45°C, GNPs was formed in the reduction of metallic ions to zero valence gold by chrysanthemum extracts or tea beverages. And the resultant solution exhibited a characteristic surface plasmon resonance band of GNPs centered at about 545 nm, responsible for its vivid light pink or wine red color. The optical properties of GNPs formed correlate well with antioxidant activity of test samples. As a result, the antioxidant functional evaluation of chrysanthemum extracts and beverages could be performed by this GNPs-based assay with a spectrophotometer or in visual analysis to a certain extent. Our present method based on the sample-mediated generation and growth of GNPs is rapid, convenient, inexpensive, and also demonstrates a new possibility for the application of nanotechnology in food science. Moreover, this present work provides some useful information for in-depth research of involving chrysanthemum. Copyright © 2011 Elsevier B.V. All rights reserved.

Antioxidant and antibacterial properties of green, black, and herbal teas of Camellia sinensis.

PubMed

Chan, Eric W C; Soh, Eu Ying; Tie, Pei Pei; Law, Yon Peng

2011-10-01

The role of non-polymeric phenolic (NP) and polymeric tannin (PT) constituents in the antioxidant and antibacterial properties of six brands of green, black, and herbal teas of Camellia sinensis were investigated. Total phenolic content (TPC) and ascorbic acid equivalent antioxidant capacity (AEAC) were assessed using the Folin-Ciocalteu and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays, respectively. Minimum inhibitory dose (MID) against Gram-positive Micrococcus luteus, Staphylococcus aureus, and Bacillus cereus, and Gram-negative. Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa was assessed using the disc-diffusion method. Teas were extracted with hot water successively three times for one hour each time. The extracts were fractionated using Sephadex LH-20 column chromatography to obtain the NP and PT constituents. Extraction yields ranged from 12 to 23%. Yields of NP fractions (70-81%) were much higher than those of PT fractions (1-11%), suggesting that the former are the major tea components. Ranking of antioxidant properties of extracts was green tea>black tea>herbal tea. For all six teas, antioxidant properties of PT fractions were significantly higher than extracts and NP fractions. Extracts and fractions of all six teas showed no activity against the three Gram-negative bacteria. Green teas inhibited all three Gram-positive bacteria with S. aureus being the least susceptible. Black and herbal teas inhibited the growth of M. luteus and B. cereus, but not S. aureus. The most potent were the PT fractions of Boh Cameron Highlands and Ho Yan Hor with MID of 0.01 and 0.03 mg/disc against M. luteus. Results suggested that NP constituents are major contributors to the antioxidant and antibacterial properties of teas of C. sinensis. Although PT constituents have stronger antioxidant and antibacterial properties, they constitute only a minor component of the teas.

Chemical composition, plant secondary metabolites, and minerals of green and black teas and the effect of different tea-to-water ratios during their extraction on the composition of their spent leaves as potential additives for ruminants.

PubMed

Ramdani, Diky; Chaudhry, Abdul Shakoor; Seal, Chris J

2013-05-22

This study characterized the chemical composition of green and black teas as well as their spent tea leaves (STL) following boiling in water with different tea-to-water ratios. The green and black tea leaves had statistically similar (g/kg dry matter (DM), unless stated otherwise) DM (937 vs 942 g/kg sample), crude protein (240 vs 242), and ash (61.8 vs 61.4), but green tea had significantly higher (g/kg DM) total phenols (231 vs 151), total tannins (204 vs 133), condensed tannins (176 vs 101), and total saponins (276 vs 86.1) and lower neutral detergent fiber (254 vs 323) and acid detergent fiber (211 vs 309) than the black tea leaves. There was no significant difference between the green and black tea leaves for most mineral components except Mn, which was significantly higher in green tea leaves, and Na and Cu, which were significantly higher in black tea leaves. A higher tea-to-water ratio during extraction significantly reduced the loss of soluble compounds into water and hence yielded more nutrient-rich STL. On the basis of these analyses it appears that the green and black tea leaves alongside their STL have the potential for use as sources of protein, fiber, secondary metabolites, and minerals in ruminant diets. The presence of high levels of plant secondary metabolites in either tea leaves or their STL suggests that they may have potential for use as natural additives in ruminant diets.

Decaffeinated green and black tea polyphenols decrease weight gain and alter microbiome populations and function in diet-induced obese mice.

PubMed

Henning, Susanne M; Yang, Jieping; Hsu, Mark; Lee, Ru-Po; Grojean, Emma M; Ly, Austin; Tseng, Chi-Hong; Heber, David; Li, Zhaoping

2017-09-30

Decaffeinated green tea (GT) and black tea (BT) polyphenols inhibit weight gain in mice fed an obesogenic diet. Since the intestinal microflora is an important contributor to obesity, it was the objective of this study to determine whether the intestinal microflora plays a role in the anti-obesogenic effect of GT and BT. C57BL/6J mice were fed a high-fat/high-sucrose diet (HF/HS, 32% energy from fat; 25% energy from sucrose) or the same diet supplemented with 0.25% GTP or BTP or a low-fat/high-sucrose (LF/HS, 10.6% energy from fat, 25% energy from sucrose) diet for 4 weeks. Bacterial composition was assessed by MiSeq sequencing of the 16S rRNA gene. GTP and BTP diets resulted in a decrease of cecum Firmicutes and increase in Bacteroidetes. The relative proportions of Blautia, Bryantella, Collinsella, Lactobacillus, Marvinbryantia, Turicibacter, Barnesiella, and Parabacteroides were significantly correlated with weight loss induced by tea extracts. BTP increased the relative proportion of Pseudobutyrivibrio and intestinal formation of short-chain fatty acids (SCFA) analyzed by gas chromatography. Cecum propionic acid content was significantly correlated with the relative proportion of Pseudobutyrivibrio. GTP and BTP induced a significant increase in hepatic 5'adenosylmonophosphate-activated protein kinase (AMPK) phosphorylation by 70 and 289%, respectively (P < 0.05) determined by Western blot. In summary, both BTP and GTP induced weight loss in association with alteration of the microbiota and increased hepatic AMPK phosphorylation. We hypothesize that BTP increased pAMPK through increased intestinal SCFA production, while GTPs increased hepatic AMPK through GTP present in the liver.

Chloride channel blockers promote relaxation of TEA-induced contraction in airway smooth muscle

PubMed Central

Yim, Peter D.; Gallos, George; Perez-zoghbi, Jose F.; Trice, Jacquelyn; Zhang, Yi; Siviski, Matthew; Sonett, Joshua; Emala, Charles W.

2014-01-01

Enhanced airway smooth muscle (ASM) contraction is an important component in the pathophysiology of asthma. We have shown that ligand gated chloride channels modulate ASM contractile tone during the maintenance phase of an induced contraction, however the role of chloride flux in depolarization-induced contraction remains incompletely understood. To better understand the role of chloride flux under these conditions, muscle force (human ASM, guinea pig ASM), peripheral small airway luminal area (rat ASM) and airway smooth muscle plasma membrane electrical potentials (human cultured ASM) were measured. We found ex vivo guinea pig airway rings, human ASM strips and small peripheral airways in rat lungs slices relaxed in response to niflumic acid following depolarization-induced contraction induced by K+ channel blockade with tetraethylammonium chloride (TEA). In isolated human airway smooth muscle cells TEA induce depolarization as measured by a fluorescent indicator or whole cell patch clamp and this depolarization was reversed by niflumic acid. These findings demonstrate that ASM depolarization induced contraction is dependent on chloride channel activity. Targeting of chloride channels may be a novel approach to relax hypercontractile airway smooth muscle in bronchoconstrictive disorders. PMID:24662476

Chloride channel blockers promote relaxation of TEA-induced contraction in airway smooth muscle.

PubMed

Yim, Peter D; Gallos, George; Perez-Zoghbi, Jose F; Trice, Jacquelyn; Zhang, Yi; Siviski, Matthew; Sonett, Joshua; Emala, Charles W

2013-01-01

Enhanced airway smooth muscle (ASM) contraction is an important component in the pathophysiology of asthma. We have shown that ligand gated chloride channels modulate ASM contractile tone during the maintenance phase of an induced contraction, however the role of chloride flux in depolarization-induced contraction remains incompletely understood. To better understand the role of chloride flux under these conditions, muscle force (human ASM, guinea pig ASM), peripheral small airway luminal area (rat ASM) and airway smooth muscle plasma membrane electrical potentials (human cultured ASM) were measured. We found ex vivo guinea pig airway rings, human ASM strips and small peripheral airways in rat lungs slices relaxed in response to niflumic acid following depolarization-induced contraction induced by K(+) channel blockade with tetraethylammonium chloride (TEA). In isolated human airway smooth muscle cells TEA induce depolarization as measured by a fluorescent indicator or whole cell patch clamp and this depolarization was reversed by niflumic acid. These findings demonstrate that ASM depolarization induced contraction is dependent on chloride channel activity. Targeting of chloride channels may be a novel approach to relax hypercontractile airway smooth muscle in bronchoconstrictive disorders.

Green tea, red wine and lemon extracts reduce experimental tumor growth and cancer drug toxicity.

PubMed

Zaletok, S P; Gulua, L; Wicker, L; Shlyakhovenko, V A; Gogol, S; Orlovsky, O; Karnaushenko, O V; Verbinenko, A; Milinevska, V; Samoylenko, O; Todor, I; Turmanidze, T

2015-12-01

To evaluate antitumor effect of plant polyphenol extracts from green tea, red wine lees and/or lemon peel alone and in combination with antitumor drugs on the growth of different transplanted tumors in experimental animals. Green tea extract (GTE) was prepared from green tea infusion. GTE-based composites of red wine (GTRW), lemon peel (GTRWL) and/or NanoGTE as well as corresponding nanocomposites were prepared. The total polyphenolics of the different GTE-based extracts ranged from 18.0% to 21.3%. The effects of GTE-based extracts were studied in sarcoma 180, Ehrlich carcinoma, B16 melanoma, Ca755 mammary carcinoma, P388 leukemia, L1210 leukemia, and Guerin carcinoma (original, cisplatin-resistant and doxorubicin-resistant variants). The extracts were administered as 0.1% solution in drinking water (0.6-1.0 mg by total polyphenolics per mouse per day and 4.0-6.3 mg per rat per day). Tumor growth inhibition (TGI) in mice treated with NanoGTE, cisplatin or cisplatin + NanoGTE was 27%, 55% and 78%, respectively, in Sarcoma 180%, 21%, 45% and 59%, respectively, in Ehrlich carcinoma; and 8%, 13% and 38%, respectively in B16 melanoma. Composites of NanoGTE, red wine, and lemon peel (NanoGTRWL) enhanced the antitumor effects of cyclophosphamide in mice with Ca755 mammary carcinoma. The treatment with combination of NanoGTE and inhibitors of polyamines (PA) synthesis (DFMO + MGBG) resulted in significant TGI of P388 leukemia (up to 71%) and L1210 leukemia. In rats transplanted with Guerin carcinoma (parental strain), treatment with GTRW or GTE alone resulted in 25-28% TGI vs. 55-68% TGI in cisplatin-treated animals. The inhibition observed in the case of combination of GTE or GTRW with cisplatin was additive giving 81-88% TGI. Similar effects were observed when combinations of the cytostatics with GTE (or NanoGTE) were tested against cisplatin- or doxorubicin-resistant Guerin carcinoma. Moreover, the plant extracts lowered side toxicity of the drugs. Treatment with GTE

Antidiabetic Effects of Tea.

PubMed

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.

Green tea extract suppresses NFκB activation and inflammatory responses in diet-induced obese rats with nonalcoholic steatohepatitis.

PubMed

Park, Hea Jin; Lee, Ji-Young; Chung, Min-Yu; Park, Young-Ki; Bower, Allyson M; Koo, Sung I; Giardina, Charles; Bruno, Richard S

2012-01-01

Nonalcoholic steatohepatitis (NASH) is characterized by oxidative stress and inflammatory responses that exacerbate liver injury. The objective of this study was to determine whether the antioxidant and antiinflammatory activities of green tea extract (GTE) would protect against NASH in a model of diet-induced obesity. Adult Wistar rats were fed a low-fat (LF) diet or high-fat (HF) diet containing no GTE or GTE at 1% or 2% (HF+2GTE) for 8 wk. The HF group had greater (P ≤ 0.05) serum alanine (ALT) and aspartate aminotransferases and hepatic lipids than the LF group. Both GTE groups had lower ALT and hepatic lipid than the HF group. In liver and epididymal adipose, the HF group had lower glutathione as well as greater mRNA and protein expression of TNFα and monocyte chemoattractant protein-1 (MCP-1) and NFκB binding activity than the LF group. Compared to the HF group, the HF+2GTE group had greater glutathione and lower protein and mRNA levels of inflammatory cytokines in both tissues. NFκB binding activities at liver and adipose were also lower, likely by inhibiting the phosphorylation of inhibitor of NFκB. NFκB binding activities in liver and adipose (P ≤ 0.05; r = 0.62 and 0.46, respectively) were correlated with ALT, and hepatic NFκB binding activity was inversely related to liver glutathione (r = -0.35). These results suggest that GTE-mediated improvements in glutathione status are associated with the inhibition of hepatic and adipose inflammatory responses mediated by NFκB, thereby protecting against NASH.

Tea enhances insulin activity.

PubMed

Anderson, Richard A; Polansky, Marilyn M

2002-11-20

The most widely known health benefits of tea relate to the polyphenols as the principal active ingredients in protection against oxidative damage and in antibacterial, antiviral, anticarcinogenic, and antimutagenic activities, but polyphenols in tea may also increase insulin activity. The objective of this study was to determine the insulin-enhancing properties of tea and its components. Tea, as normally consumed, was shown to increase insulin activity >15-fold in vitro in an epididymal fat cell assay. Black, green, and oolong teas but not herbal teas, which are not teas in the traditional sense because they do not contain leaves of Camellia senensis, were all shown to increase insulin activity. High-performance liquid chromatography fractionation of tea extracts utilizing a Waters SymmetryPrep C18 column showed that the majority of the insulin-potentiating activity for green and oolong teas was due to epigallocatechin gallate. For black tea, the activity was present in several regions of the chromatogram corresponding to, in addition to epigallocatechin gallate, tannins, theaflavins, and other undefined compounds. Several known compounds found in tea were shown to enhance insulin with the greatest activity due to epigallocatechin gallate followed by epicatechin gallate, tannins, and theaflavins. Caffeine, catechin, and epicatechin displayed insignificant insulin-enhancing activities. Addition of lemon to the tea did not affect the insulin-potentiating activity. Addition of 5 g of 2% milk per cup decreased the insulin-potentiating activity one-third, and addition of 50 g of milk per cup decreased the insulin-potentiating activity approximately 90%. Nondairy creamers and soy milk also decreased the insulin-enhancing activity. These data demonstrate that tea contains in vitro insulin-enhancing activity and the predominant active ingredient is epigallocatechin gallate.

Effects of green tea tannin on cisplatin-induced nephropathy in LLC-PK1 cells and rats.

PubMed

Yokozawa, T; Nakagawa, T; Lee, K I; Cho, E J; Terasawa, K; Takeuchi, S

1999-11-01

A study was conducted to clarify whether green tea tannin ameliorated cisplatin-induced renal injury in terms of lactate dehydrogenase and malondialdehyde leakage from a renal epithelial cell line, swine-derived LLC-PK1 cells in culture. Green tea tannin was shown to suppress the cytotoxicity of cisplatin, the suppressive effect increasing with the dose of green tea tannin. The effect of cisplatin was then investigated in rats given green tea tannin for 40 days before cisplatin administration and in control rats given no green tea tannin. In control rats, blood, urinary and renal parameters and the activities of antioxidative enzymes in renal tissue deviated from the normal range, indicating dysfunction of the kidneys. In contrast, rats given green tea tannin showed decreased blood levels of urea nitrogen and creatinine, and decreased urinary levels of protein and glucose, reflecting less damage to the kidney. In this group, the activity of catalase in the renal tissue was increased, while the level of malondialdehyde was decreased, suggesting the involvement of radicals in the normalizing of kidney function. Based on the evidence available it appeared that green tea tannin eliminated oxidative stress and was beneficial to renal function.

Consumption of milk-protein combined with green tea modulates diet-induced thermogenesis.

PubMed

Hursel, Rick; Westerterp-Plantenga, Margriet S

2011-08-01

Green tea and protein separately are able to increase diet-induced thermogenesis. Although their effects on long-term weight-maintenance were present separately, they were not additive. Therefore, the effect of milk-protein (MP) in combination with green tea on diet-induced thermogenesis (DIT) was examined in 18 subjects (aged 18-60 years; BMI: 23.0 ± 2.1 kg/m(2)). They participated in an experiment with a randomized, 6 arms, crossover design, where energy expenditure and respiratory quotient (RQ) were measured. Green tea (GT)vs. placebo (PL) capsules were either given in combination with water or with breakfasts containing milk protein in two different dosages: 15 g (15 MP) (energy% P/C/F: 15/47/38; 1.7 MJ/500 mL), and 3.5 g (3.5 MP) (energy% P/C/F: 41/59/0; 146.4 kJ/100 mL). After measuring resting energy expenditure (REE) for 30 min, diet-induced energy expenditure was measured for another 3.5 h after the intervention. There was an overall significant difference observed between conditions (p < 0.001). Post-hoc, areas under the curve (AUCs) for diet-induced energy expenditure were significantly different (P ≤ 0.001) for GT + water (41.11 [91.72] kJ·3.5 h) vs. PL + water (10.86 [28.13] kJ·3.5 h), GT + 3.5 MP (10.14 [54.59] kJ·3.5 h) and PL + 3.5 MP (12.03 [34.09] kJ·3.5 h), but not between GT + 3.5 MP, PL + 3.5 MP and PL + water, indicating that MP inhibited DIT following GT. DIT after GT + 15 MP (167.69 [141.56] kJ·3.5 h) and PL + 15 MP (168.99 [186.56] kJ·3.5 h) was significantly increased vs. PL + water (P < 0.001), but these were not different from each other indicating that 15 g MP stimulated DIT, but inhibited the GT effect on DIT. No significant differences in RQ were seen between conditions for baseline and post-treatment. In conclusion, consumption of milk-protein inhibits the effect of green tea on DIT.

An EPR study on tea: Identification of paramagnetic species, effect of heat and sweeteners

NASA Astrophysics Data System (ADS)

Bıyık, Recep; Tapramaz, Recep

2009-10-01

Tea ( Camellia Sinensis) is the most widely consumed beverage in the world, and is known to be having therapeutic, antioxidant and nutritional effects. Electron paramagnetic resonance (EPR) spectral studies made on the tea cultivated along the shore of Black Sea, Turkey, show Mn 2+ and Fe 3+ centers in green tea leaves and in black tea extract. Dry black tea flakes and dry extract show additional sharp line attributed to semiquinone radical. The origins of the paramagnetic species in black tea are defined and discussed. Effect of humidity and heat are investigated. It is observed that dry extract of black tea melts at 100 °C and the semiquinone radical lives up to 140 °C while Mn 2+ sextet disappears just above 100 °C in tea extract. Natural and synthetics sweeteners have different effects on the paramagnetic centers. White sugar (sucrose) quenches the Mn 2+ and semiquinone lines in black tea EPR spectrum, and glucose, fructose, lactose and maltose quench Fe 3+ line while synthetic sweeteners acesulfam potassium, aspartame and sodium saccharine do not have any effect on paramagnetic species in tea.

An EPR study on tea: identification of paramagnetic species, effect of heat and sweeteners.

PubMed

Biyik, Recep; Tapramaz, Recep

2009-10-15

Tea (Camellia Sinensis) is the most widely consumed beverage in the world, and is known to be having therapeutic, antioxidant and nutritional effects. Electron paramagnetic resonance (EPR) spectral studies made on the tea cultivated along the shore of Black Sea, Turkey, show Mn(2+) and Fe(3+) centers in green tea leaves and in black tea extract. Dry black tea flakes and dry extract show additional sharp line attributed to semiquinone radical. The origins of the paramagnetic species in black tea are defined and discussed. Effect of humidity and heat are investigated. It is observed that dry extract of black tea melts at 100 degrees C and the semiquinone radical lives up to 140 degrees C while Mn(2+) sextet disappears just above 100 degrees C in tea extract. Natural and synthetics sweeteners have different effects on the paramagnetic centers. White sugar (sucrose) quenches the Mn(2+) and semiquinone lines in black tea EPR spectrum, and glucose, fructose, lactose and maltose quench Fe(3+) line while synthetic sweeteners acesulfam potassium, aspartame and sodium saccharine do not have any effect on paramagnetic species in tea.

Formation and emission of linalool in tea (Camellia sinensis) leaves infested by tea green leafhopper (Empoasca (Matsumurasca) onukii Matsuda).

PubMed

Mei, Xin; Liu, Xiaoyu; Zhou, Ying; Wang, Xiaoqin; Zeng, Lanting; Fu, Xiumin; Li, Jianlong; Tang, Jinchi; Dong, Fang; Yang, Ziyin

2017-12-15

Famous oolong tea (Oriental Beauty), which is manufactured by tea leaves (Camellia sinensis) infected with tea green leafhoppers, contains characteristic volatile monoterpenes derived from linalool. This study aimed to determine the formation mechanism of linalool in tea exposed to tea green leafhopper attack. The tea green leafhopper responsible for inducing the production of characteristic volatiles was identified as Empoasca (Matsumurasca) onukii Matsuda. E. (M.) onukii attack significantly induced the emission of linalool from tea leaves (p<0.05) as a result of the up-regulation of the linalool synthases (CsLIS1 and CsLIS2) (p<0.05). Continuous mechanical damage significantly enhanced CsLIS1 and CsLIS2 expression levels and linalool emission (p<0.05). Therefore, continuous wounding was a key factor causing the formation and emission of linalool from tea leaves exposed to E. (M.) onukii attack. This information should prove helpful for the future use of stress responses of plant secondary metabolism to improve quality components of agricultural products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Planar solid phase extraction clean-up for pesticide residue analysis in tea by liquid chromatography-mass spectrometry.

PubMed

Oellig, Claudia; Schwack, Wolfgang

2012-10-19

Efficient clean-up is indispensable for preventing matrix effects in multi-residue analysis of pesticides in food by liquid and gas chromatography (LC and GC) coupled to mass spectrometry (MS). High-throughput planar solid phase extraction (HTpSPE) was recently introduced as a new clean-up concept in residue analysis of pesticides in fruit and vegetables (C. Oellig, W. Schwack, 2011 [45]). Thin-layer chromatography (TLC) was used to completely separate pesticides from matrix compounds and to focus them into a sharp zone, followed by extraction of the target zone by the TLC-MS interface. As rather challenging matrices, tea samples were chosen in this study. Besides chlorophylls and polyphenols, high amount of caffeine is co-extracted resulting in strong matrix effects both in LC-MS and GC-MS. The former HTpSPE procedure was adapted to initial extracts of green and black tea resulting in colorless extracts nearly free of matrix effects and interferences, as shown for seven chemically representative pesticides (acetamiprid, penconazole, azoxystrobin, chlorpyrifos, pirimicarb, fenarimol, and mepanipyrim). LC-MS/MS calibration curves obtained in the range of 0.002-0.5 mg/kg from matrix-matched standards and solvent standards were nearly identical and demonstrated the effectiveness of clean-up by HTpSPE. Mean recoveries determined by LC-MS/MS against solvent standards at spiking levels of 0.01 and 0.1 mg/kg ranged between 72 and 114% with relative standard deviations (RSDs) of 0.7-4.7% (n=4), while LC-MS measurements of tea samples spiked at 1 mg/kg provided recoveries of 81-104% with RSDs of 1.2-4.9% (n=6). Using LC-MS/MS, the method showed high sensitivity with signal-to-noise ratios>10 for concentrations below 0.002 mg/kg. HTpSPE of one sample was done in a few minutes, while numerous samples were cleaned in parallel at minimal costs with very low sample and solvent consumption. Copyright © 2012 Elsevier B.V. All rights reserved.

Selective removal of caffeine from tea extracts using macroporous crosslinked polyvinyl alcohol adsorbents.

PubMed

Ma, Ning; Wang, Peng; Kong, Xia; Shi, Rongfu; Yuan, Zhi; Wang, Chunhong

2012-01-01

The hydrolysis reaction of ester groups in vinyl acetate (VAc) was used to introduce hydroxyl groups into the matrix of a macroporous adsorbent, which was itself prepared by free radical suspension copolymerization of triallyl isocyanurate (TAIC) and VAc. Therefore, the copolymerization incompatibility between the hydrophilic and the hydrophobic monomer was overcome successfully and the hydrophobic matrix of the polymeric adsorbent containing a polyvinyl alcohol (PVA) segment was obtained. Introduction of the PVA segment decreased the hydrophobic adsorption affinity of the adsorbent while producing the hydrogen-bonding interaction. When isolating the two active components, polyphenols (TPh) and caffeine (CAF), from green tea extracts, this polymeric adsorbent, namely poly(TAIC-co-VA), exhibited good adsorption selectivity towards TPh over CAF. The adsorption mechanism leading to this selectivity involved a hydrophobic interaction mechanism for CAF and multiple weak hydrophobic and hydrogen-bonding interactions for TPh. The adsorption thermodynamics for TPh on poly(TAIC-co-VA) were studied. The effects of adsorbent structure and gradient desorption conditions on isolation were investigated. The result showed that adsorbent, with 20% TAIC content, was able to efficiently remove CAF from different tea extracts with different ratios of TPh and CAF. Finally, almost no CAF was detected in the TPh fraction and the recovery of TPh was greater than 95%. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Effect of Green Tea and Sour Tea (Hibiscus sabdariffa L.) Supplementation on Oxidative Stress and Muscle Damage in Athletes.

PubMed

Hadi, Amir; Pourmasoumi, Makan; Kafeshani, Marzieh; Karimian, Jahangir; Maracy, Mohammad Reza; Entezari, Mohammad Hasan

2017-05-04

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. This randomized, double-blind control trial was conducted on 54 male soccer players. Participants were randomly assigned to three groups to receive: 450 mg/d green tea extract (GTE) in the first group (n = 18), 450 mg/d sour tea extract (STE) in the second group (n = 18) and 450 mg/d maltodextrin in the control group (n = 18). Fasting whole blood samples were taken under resting conditions at the beginning and the end of the study to quantify the serum levels of muscle damage indices, aspartate aminotransferase (AST), creatine kinase (CK), lactate dehydrogenase (LDH), and oxidative stress biomarkers, malondialdehyde (MDA), and total antioxidant capacity (TAC). After six weeks intervention, athletes who received GTE and STE supplements compared with the placebo had a significantly decreased MDA level (P = 0.008). Furthermore, STE supplementation resulted in a significant increase in TAC level compared with GTE and placebo groups (P = 0.01). However, supplementation with GTE and STE had no significant effects on muscle damage indices. GTE and STE supplementation have beneficial effects on oxidative stress status in male athletes. However, both kinds of tea extract did not affect muscle damage status.

Determination of catechins in matcha green tea by micellar electrokinetic chromatography.

PubMed

Weiss, David J; Anderton, Christopher R

2003-09-05

Catechins in green tea are known to have many beneficial health properties. Recently, it has been suggested that matcha has greater potential health benefits than other green teas. Matcha is a special powdered green tea used in the Japanese tea ceremony. However, there has been no investigation to quantitate the catechin intake from matcha compared to common green teas. We have developed a rapid method of analysis of five catechins and caffeine in matcha using micellar electrokinetic chromatography. Results are presented for water and methanol extractions of matcha compared with water extraction of a popular green tea. Using a mg catechin/g of dry leaf comparison, results indicate that the concentration of epigallocatechin gallate (EGCG) available from drinking matcha is 137 times greater than the amount of EGCG available from China Green Tips green tea, and at least three times higher than the largest literature value for other green teas.

Combined treatment with Dendrobium candidum and black tea extract promotes osteoprotective activity in ovariectomized estrogen deficient rats and osteoclast formation.

PubMed

Wang, Ming-Yue; Shen, Chang; An, Meng-Fei; Xie, Chuan-Qi; Wu, Xin; Zhu, Qiang-Qiang; Sun, Bin; Huang, Yan-Ping; Zhao, Yun-Li; Wang, Xuan-Jun; Sheng, Jun

2018-05-01

Dendrobium candidum (DC) and black tea, are traditional chinese drinks, which contain multiple active ingredients. However, whether or not the combination of these two ingredients can improve osteoporosis remains unknown. This study therefore aimed to examine the effects of the combination of DC and black tea extract (BTE) on osteoporosis. Ovariectomy (OVX)-induced osteoporosis in vivo as well as receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis in vitro was selected. Results showed that OVX rats that were treated orally with a DC and BTE combination for 12 weeks maintained their calcium (Ca) and phosphorus (P) homeostasis and exhibited significantly enhanced estradiol (E 2 ) and OPG levels. This combination treatment also simultaneously reduced levels of interleukin (IL)-1β, IL-6 and improved the organ coefficients of the uterus and femur as well as BMD and BMC in OVX rats. In addition, this DC and BTE combination suppressed osteoclast differentiation in the RANKL-stimulated osteoclastogenesis of RAW 264.7 cells and effectively inhibited the expression of osteoclast-associated genes and proteins. The results of this study further highlight the fact that a combination of DC and BTE improved ovariectomy-induced osteoporosis in rats and suppressed RANKL-stimulated osteoclastogenesis in RAW 264.7 cells. This combination also significantly alleviated osteoporosis when compared to the alternative sole treatments above, due to synergistic effects among components. One partial mechanism of this combination might be the inhibition of osteoclast proliferation and the regulation of NFATC1/c-Fos expression. Copyright © 2018 Elsevier Inc. All rights reserved.

Effect of steeping temperature on antioxidant and inhibitory activities of green tea extracts against α-amylase, α-glucosidase and intestinal glucose uptake.

PubMed

Liu, Shuyuan; Ai, Zeyi; Qu, Fengfeng; Chen, Yuqiong; Ni, Dejiang

2017-11-01

The objective of the present study was to evaluate the effect of steeping temperature on the biological activities of green tea, including the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity, α-glucosidase and α-amylase inhibitory activities, and glucose uptake inhibitory activity in Caco-2 cells. Results showed that, with increasing extraction temperature, the polyphenol content increased, which contributed to enhance antioxidant activity and inhibitory effects on α-glucosidase and α-amylase. Green tea steeped at 100°C showed the highest DPPH radical-scavenging activity and inhibitory effects on α-glucosidase and α-amylase activities with EC 50 or IC 50 values of 6.15μg/mL, 0.09mg/mL, and 6.31mg/mL, respectively. However, the inhibitory potential on glucose uptake did not show an upward trend with increasing extraction temperature. Green tea steeped at 60°C had significantly stronger glucose uptake inhibitory activity (p<0.05). The integrated data suggested that steeping temperature should be considered when evaluating the biological activities of green tea. Copyright © 2017 Elsevier Ltd. All rights reserved.

Primary cancer prevention by green tea, and tertiary cancer prevention by the combination of green tea catechins and anticancer compounds.

PubMed

Fujiki, Hirota; Sueoka, Eisaburo; Watanabe, Tatsuro; Suganuma, Masami

2015-03-01

Green tea is a daily beverage, a non-oxidized non-fermented product containing at least four green tea catechins. Considering our first results when repeated applications of (-)-epigallocatechin gallate (EGCG) prevented tumor promotion in mouse skin, we have continued to look at green tea as a possible cancer preventive agent. 1) The 10-year prospective cohort study by Drs. K. Nakachi and K. Imai revealed that drinking 10 Japanese-size cups (120 mL/cup) of green tea per day delayed cancer onset in humans by 7.3 years among females and by 3.2 years among males. The delay of cancer onset is of course significant evidence of primary cancer prevention in humans. 2) In collaboration with Dr. H. Moriwaki's group we successfully presented a prototype of tertiary cancer prevention showing that 10 Japanese-size cups of green tea daily, supplemented with tablets of green tea extract (G.T.E), reduced recurrence of colorectal adenomas in polypectomy patients by 51.6% (from 31% to 15%). 3) In 1999, we first reported that the combination of green tea catechins and non-steroidal anti-inflammatory drugs showed synergistic anticancer effects in both in vitro and in vivo experiments, along with elucidation of the mechanism. 4) Further studies by other investigators have revealed that various combinations of EGCG or green tea extract and anticancer compounds inhibit tumor volume in xenograft mouse models implanted with various human cancer cell lines. Green tea is a cancer preventive, and green tea catechins act as synergists with anticancer compounds.

Diversity of lactic acid bacteria from Miang, a traditional fermented tea leaf in northern Thailand and their tannin-tolerant ability in tea extract.

PubMed

Chaikaew, Siriporn; Baipong, Sasitorn; Sone, Teruo; Kanpiengjai, Apinun; Chui-Chai, Naradorn; Asano, Kozo; Khanongnuch, Chartchai

2017-09-01

The microbiota of lactic acid bacteria (LAB) in thirty-five samples of Miang, a traditional fermented tea leaf product, collected from twenty-two different regions of eight provinces in upper northern Thailand was revealed through the culture-dependent technique. A total of 311 presumptive LAB strains were isolated and subjected to clustering analysis based on repetitive genomic element-PCR (rep-PCR) fingerprinting profiles. The majority of the strains belonged to the Lactobacillus genera with an overwhelming predominance of the Lb. plantarum group. Further studies of species-specific PCR showed that 201 of 252 isolates in the Lb. plantarum group were Lb. plantarum which were thus considered as the predominant LAB in Miang, while the other 51 isolates belonged to Lb. pentosus. In contrast to Lb. plantarum, there is a lack of information on the tannase gene and the tea tannin-tolerant ability of Lb. pentosus. Of the 51 Lb. pentosus isolates, 33 were found to harbor the genes encoding tannase and shared 93-99% amino acid identity with tannase obtained from Lb. pentosus ATCC 8041 T . Among 33 tannase gene-positive isolates, 23 isolates exhibited high tannin- tolerant capabilities when cultivated on de Man Rogosa and Sharpe agar-containing bromocresol purple (0.02 g/L, MRS-BCP) supplemented with 20% (v/v) crude tea extract, which corresponded to 2.5% (w/v) tannins. These Lb. pentosus isolates with high tannin-tolerant capacity are expected to be the high potential strains for functional tannase production involved in Miang fermentation as they will bring about certain benefits and could be used to improve the fermentation of tea products.

[Induction of NAD(P)H: quinone reductase by anticarcinogenic ingredients of tea].

PubMed

Qi, L; Han, C

1998-09-30

By assaying the activity of NAD(P)H: quinone reductase (QR) in Hep G2 cells exposed to inducing agents, a variety of ingredients in tea, we compared their abilities on inducing QR and preventing cancer. The results showed that tea polyphenols, tea pigments and mixed tea were all able to induce the activity of QR significantly. The single-component ingredients of tea polyphenols and tea pigments, including thearubigens, EGCG and ECG, also enhanced the activity of QR. But EGC, EC, theaflavins, tea polysaccharide and tea caffeine, showed no apparent induction of QR. We found that among those tea ingredients studied, the multi-component ingredients were more effective than the single-component ones. So we thought that the abilities of antioxidation and cancer prevention of tea depended on the combined effects of several kinds of active ingredients, which mainly include tea polyphenols and tea pigments.

White and green teas (Camellia sinensis var. sinensis): variation in phenolic, methylxanthine, and antioxidant profiles.

PubMed

Unachukwu, Uchenna J; Ahmed, Selena; Kavalier, Adam; Lyles, James T; Kennelly, Edward J

2010-08-01

Recent investigations have associated white teas with anti-carcinogenic, immune-boosting, and antioxidative properties that may impact human health in a manner comparable to green teas. An in-depth chemical analysis of white tea types was conducted to quantify polyphenols and antioxidant potential of 8 commercially available white teas, and compare them to green tea. Extraction and HPLC protocols were optimized and validated for the quantification of 9 phenolic and 3 methylxanthine compounds to examine inter- and intra-variation in white and green tea types and subtypes. A sampling strategy was devised to assess various subtypes procured from different commercial sources. Variation in antioxidant activity and total phenolic content (TPC) of both tea types was further assessed by the 1-1-diphenyl-2-picrylhydrazyl (DPPH) and Folin-Ciocalteau (F-C) assays, respectively. Total catechin content (TCC) for white teas ranged widely from 14.40 to 369.60 mg/g of dry plant material for water extracts and 47.16 to 163.94 mg/g for methanol extracts. TCC for green teas also ranged more than 10-fold, from 21.38 to 228.20 mg/g of dry plant material for water extracts and 32.23 to 141.24 mg/g for methanol extracts. These findings indicate that statements suggesting a hierarchical order of catechin content among tea types are inconclusive and should be made with attention to a sampling strategy that specifies the tea subtype and its source. Certain white teas have comparable quantities of total catechins to some green teas, but lesser antioxidant capacity, suggesting that white teas have fewer non-catechin antioxidants present. Practical Application: In this investigation white and green teas were extracted in ways that mimic common tea preparation practices, and their chemical profiles were determined using validated analytical chemistry methods. The results suggest certain green and white tea types have comparable levels of catechins with potential health promoting qualities

Supplementation with lutein or lutein plus green tea extracts does not change oxidative stress in adequately nourished older adults1

PubMed Central

Li, Lei; Chen, C-Y. Oliver; Aldini, Giancarlo; Johnson, Elizabeth J; Rasmussen, Helen; Yoshida, Yasukazu; Niki, Etsuo; Blumberg, Jeffrey B; Russell, Robert M.; Yeum, Kyung-Jin

2009-01-01

Epigallocatechin gallate, a major component of green tea polyphenols, protects against the oxidation of fat-soluble antioxidants including lutein. The current study determined the effect of relatively high but a dietary achievable dose of lutein or lutein plus green tea extract on antioxidant status. Healthy subjects (50–70 yrs) were randomly assigned to one of 2 groups, (n=20 in each group) 1) a lutein (12mg/d) supplemented group, or 2) a lutein (12 mg/d) plus green tea extract (200 mg/d) supplemented group. After 2 wks of run-in period consumed less than two servings of lightly-colored fruit & vegetables in their diet, each group was treated for 112 days while on their customary regular diets. Plasma carotenoids including lutein, tocopherols, flavanols and ascorbic acid were analyzed by HPLC-UVD and -ECD systems; total antioxidant capacity by fluorometry; lipid peroxidation by malondialdehyde using a HPLC system with a fluorescent detector and by total hydroxyoctadecadienoic acids using a GC/MS. Plasma lutein, total carotenoids and ascorbic acid concentrations of subjects in either lutein group or lutein plus green tea extract group were significantly increased (p<0.05) at 4 wks and throughout the 16 wks study period. However, no significant changes from baseline in any biomarker of overall antioxidant activity or lipid peroxidation of the subjects were seen in either group. Our results indicate that an increase of antioxidant concentrations within a range that could readily be achieved in a healthful diet does not affect in vivo antioxidant status in normal healthy subjects when sufficient amounts of antioxidants already exist. PMID:19447020

Pu-erh Tea Inhibits Tumor Cell Growth by Down-Regulating Mutant p53

PubMed Central

Zhao, Lanjun; Jia, Shuting; Tang, Wenru; Sheng, Jun; Luo, Ying

2011-01-01

Pu-erh tea is a kind of fermented tea with the incorporation of microorganisms’ metabolites. Unlike green tea, the chemical characteristics and bioactivities of Pu-erh tea are still not well understood. Using water extracts of Pu-erh tea, we analyzed the tumor cell growth inhibition activities on several genetically engineered mouse tumor cell lines. We found that at the concentration that did not affect wild type mouse embryo fibroblasts (MEFs) growth, Pu-erh tea extracts could inhibit tumor cell growth by down-regulated S phase and cause G1 or G2 arrest. Further study showed that Pu-erh tea extracts down-regulated the expression of mutant p53 in tumor cells at the protein level as well as mRNA level. The same concentration of Pu-erh tea solution did not cause p53 stabilization or activation of its downstream pathways in wild type cells. We also found that Pu-erh tea treatment could slightly down-regulate both HSP70 and HSP90 protein levels in tumor cells. These data revealed the action of Pu-erh tea on tumor cells and provided the possible mechanism for Pu-erh tea action, which explained its selectivity in inhibiting tumor cells without affecting wild type cells. Our data sheds light on the application of Pu-erh tea as an anti-tumor agent with low side effects. PMID:22174618

Amelioration of iron toxicity: A mechanism for aluminum-induced growth stimulation in tea plants.

PubMed

Hajiboland, Roghieh; Barceló, Juan; Poschenrieder, Charlotte; Tolrà, Roser

2013-11-01

Tea plants (Camellia sinensis) are well adapted to acid soils with high Al availability. These plants not only accumulate high leaf Al concentrations, but also respond to Al with growth stimulation. Decreased oxidative stress has been associated with this effect. Why tea plants not exposed to Al suffer from oxidative stress has not been clarified. In this study, hydroponically grown tea plants treated with 0 to 300 μM Al were analyzed for growth, Al and Fe accumulation, and Al distribution by means of morin and hematoxylin staining. Roots of control plants stained black with hematoxylin. This indicates the formation of a Fe-hematoxylin complex. Young leaves of controls accumulated more than 1000 mg Fe kg(-1) dry weight. This concentration is above the Fe-toxicity threshold in most species. Supply of Al stimulated growth and reduced Fe uptake and transport. These results indicate that Al-induced growth stimulation might be due to alleviation of a latent Fe toxicity occurring in tea plants without Al supply. © 2013.

Common tea formulations modulate in vitro digestive recovery of green tea catechins.

PubMed

Green, Rodney J; Murphy, Angus S; Schulz, Burkhard; Watkins, Bruce A; Ferruzzi, Mario G

2007-09-01

Epidemiological evidence suggests a role for tea catechins in reduction of chronic disease risk. However, stability of catechins under digestive conditions is poorly understood. The objective of this study was to characterize the effect of common food additives on digestive recovery of tea catechins. Green tea water extracts were formulated in beverages providing 4.5, 18, 23, and 3.5 mg per 100 mL epicatechin (EC), epigallocatechin (EGC), epigallocatechin-gallate (EGCG), and epicatechin-gallate (ECG), respectively. Common commercial beverage additives; citric acid (CA), BHT, EDTA, ascorbic acid (AA), milk (bovine, soy, and rice), and citrus juice (orange, grapefruit, lemon, and lime) were formulated into finished tea beverages at incremental dosages. Samples were then subjected to in vitro digestion simulating gastric and small intestinal conditions with pre- and post-digestion catechin profiles assessed by HPLC. Catechin stability in green tea was poor with <20% total catechins remaining post-digestion. EGC and EGCG were most sensitive with less, not double equals 10% recovery. Teas formulated with 50% bovine, soy, and rice milk increased total catechin recovery significantly to 52, 55, and 69% respectively. Including 30 mg AA in 250 mL of tea beverage significantly (p<0.05) increased catechin recovery of EGC, EGCG, EC, and ECG to 74, 54, 82, and 45% respectively. Juice preparation resulted in the highest recovery of any formulation for EGC (81-98%), EGCG (56-76%), EC (86-95%), and ECG (30-55%). These data provide evidence that tea consumption practices and formulation factors likely impact catechin digestive recovery and may result in diverse physiological profiles.

Tannase-converted green tea catechins and their anti-wrinkle activity in humans.

PubMed

Hong, Yang-Hee; Jung, Eun Young; Shin, Kwang-Soon; Yu, Kwang-Won; Chang, Un Jae; Suh, Hyung Joo

2013-06-01

This study was performed to investigate the anti-wrinkle effects of topical applications of green tea extract with high antioxidant activity by tannase treatment. Increases in gallic acid (GA), (-)-epigallocatechin (EGC), and (-)-epicatechin (EC) were observed in the green tea extract after tannase treatment. This study was performed to investigate the anti-wrinkle effects of topical applications of green tea extract exhibiting high antioxidant activity after tannase treatment. Subjects, randomly divided into two groups, received the application of either tannase-converted green tea extract (TGE) or normal green tea extract (NGE) on their crow's feet for 8 weeks. The anti-wrinkle effects were evaluated with two methods: (i) self-assessment; and (ii) average roughness of skin surface (R(a), R(z), and R(t) value) using skin replica and Skin-Visiometer SV 600. The scavenging abilities of TGE against radicals were significantly higher compared to NGE. The evaluation of skin wrinkle index values after 8 weeks of treatment showed that reductions of R(a), R(z), and R(t) values in the TGE group were significantly greater than in the NGE group, which indicated that tannase treatment improved the anti-wrinkle effects of green tea extract. According to the overall ratings for wrinkle treatment by applying the formulations, most of the TGE group (63.60%) reported marked or moderate improvement in wrinkles compared with only 36.30% of the NGE group. Tannase treatment can improve the antioxidant activity of green tea extract, conferring anti-wrinkle activities. These results suggest that TGE may have beneficial properties as an anti-wrinkle agent. © 2013 Wiley Periodicals, Inc.

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

PubMed Central

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

Changes of constituents and activity to apoptosis and cell cycle during fermentation of tea.

PubMed

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.

Bioassay-guided purification and identification of antimicrobial components in Chinese green tea extract.

PubMed

Si, Weiduo; Gong, Joshua; Tsao, Rong; Kalab, Milosh; Yang, Raymond; Yin, Yulong

2006-09-01

The Chinese green tea extract was found to strongly inhibit the growth of major food-borne pathogens, Escherichia coli O157:H7, Salmonella Typhimurium DT104, Listeria monocytogenes, Staphylococcus aureus, and a diarrhoea food-poisoning pathogen Bacillus cereus, by 44-100% with the highest activity found against S. aureus and lowest against E. coli O157:H7. A bioassay-guided fractionation technique was used for identifying the principal active component. A simple and efficient reversed-phase high-speed counter-current chromatography (HSCCC) method was developed for the separation and purification of four bioactive polyphenol compounds, epicatechin gallate (ECG), epigallocatechin gallate (EGCG), epicatechin (EC), and caffeine (CN). The structures of these polyphenols were confirmed with mass spectrometry. Among the four compounds, ECG and EGCG were the most active, particularly EGCG against S. aureus. EGCG had the lowest MIC90 values against S. aureus (MSSA) (58 mg/L) and its methicilin-resistant S. aureus (MRSA) (37 mg/L). Scanning electron microscopy (SEM) studies showed that these two compounds altered bacterial cell morphology, which might have resulted from disturbed cell division. This study demonstrated a direct link between the antimicrobial activity of tea and its specific polyphenolic compositions. The activity of tea polyphenols, particularly EGCG on antibiotics-resistant strains of S. aureus, suggests that these compounds are potential natural alternatives for the control of bovine mastitis and food poisoning caused by S. aureus.

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

PubMed

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.

Simplified recovery of enzymes and nutrients in sweet potato wastewater and preparing health black tea and theaflavins with scrap tea.

PubMed

Li, Qing-Rong; Luo, Jia-Ling; Zhou, Zhong-Hua; Wang, Guang-Ying; Chen, Rui; Cheng, Shi; Wu, Min; Li, Hui; Ni, He; Li, Hai-Hang

2018-04-15

The industry discards generous organic wastewater in sweet potato starch factory and scrap tea in tea production. A simplified procedure to recover all biochemicals from the wastewater of sweet potato starch factory and use them to make health black tea and theaflavins from scrap green tea was developed. The sweet potato wastewater was sequentially treated by isoelectric precipitation, ultrafiltration and nanofiltration to recover polyphenol oxidase (PPO), β-amylase, and small molecular fractions, respectively. The PPO fraction can effectively transform green tea extracts into black tea with high content of theaflavins through the optimized fed-batch feeding fermentation. The PPO transformed black tea with sporamins can be used to make health black tea, or make theaflavins by fractionation with ethyl acetate. This work provides a resource- and environment-friendly approach for economically utilizing the sweet potato wastewater and the scrap tea, and making biochemical, nutrient and health products. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigation of six bioactive anthraquinones in slimming tea by accelerated solvent extraction and high performance capillary electrophoresis with diode-array detection.

PubMed

Wang, Ning; Su, Ming; Liang, Shuxuan; Sun, Hanwen

2016-05-15

A rapid and effective method for effective separation and rapid simultaneous determination of six bioactive anthraquinones by capillary zone electrophoresis was developed. An accelerated solvent extraction procedure was used for the extraction of anthraquinones from slimming tea. Under the optimized conditions, the effective separation of six anthraquinones was achieved within 8 min. Good linearity was achieved, with a correlation coefficient (r) of ⩾ 0.999. The limit of detection ranged from 0.33 to 1.40 μg mL(-1). The intra- and inter-day relative standard deviation (RSD) of the six analytes was in the range of 2.3-3.9% and 3.2-4.9%, respectively. The average recovery of the six analytes from real tea samples was in the range of 86.15-98.30% with the RSD of 1.04-4.99%. The developed and validated method has speediness, high sensitivity, recovery and precision, and can be applied for the quality control of slimming tea. Copyright © 2015 Elsevier Ltd. All rights reserved.

Green tea: Health benefits as cancer preventive for humans.

PubMed

Fujiki, Hirota

2005-01-01

Green tea is an acknowledged cancer preventive in Japan. The aim of this review article is to develop the concept of cancer prevention with green tea beverage for humans, which has largely been our exclusive research territory. This paper briefly reviews several topics, beginning with the introduction of our initial work on penta-O-galloyl-beta-D-glucose and (-)-epigallocatechin gallate (EGCG), the main constituent of green tea extract. The mechanisms of EGCG action, particularly the reduction of TNF-alpha are discussed, and we show how use of 3H-EGCG revealed a wide range of target organs for cancer prevention. The results of an epidemiological study in Saitama Prefecture allowed us to determine the cancer preventive amount of green tea-10 Japanese-size cups per day, about 2.5 g green tea extract-which made it possible for us to introduce the two-stage strategy of cancer prevention with green tea. The first stage is the delay of cancer onset for the general population. The second stage is the prevention of recurrence of cancer for patients following cancer treatment. Combination cancer prevention with green tea and cancer preventive drugs is proving especially beneficial for Japanese, who drink green tea every day. And finally, the stimulating comments of Prof. Jim Watson have encouraged green tea scientists. Copyright (c) 2005 The Japan Chemical Journal Forum and Wiley Periodicals, Inc.

Formation of enriched black tea extract loaded chitosan nanoparticles via electrospraying

NASA Astrophysics Data System (ADS)

Hammond, Samuel James

Creating nanoparticles of beneficial nutraceuticals and pharmaceuticals has had a large surge of research due to the enhancement of absorption and bioavailability by decreasing their size. One of these ways is by electrohydrodynamic atomization, also known as electrospraying. In general, this novel process is done by forcing a liquid through a capillary nozzle and which is subjected to an electrical field. While there are different ways to create nanoparticles, the novel method of electrospraying can be beneficial over other types of nanoparticle formation. Reasons include high control over particle size and distribution by altering electrospray parameters (voltage, flow rate, distance, and time), higher encapsulation efficiency than other methods, and also it is a one step process without exposure to extreme conditions (Gomez-Estaca et. al. 2012, Jaworek and Sobcyzk 2008). The current study aimed to create a chitosan encapsulated theaflavin-2 enriched black tea extract (BTE) nanoparticles via electrospraying. The first step of this process was to create the smallest chitosan nanoparticles possible by altering the electrospray parameters and the chitosan-acetic acid solution parameters. The solution properties altered include chitosan molecular weight, acetic acid concentration, and chitosan concentration. Specifically, the electrospray parameters such as voltage, flow rate and distance from syringe to collector are the most important in determining particle size. After creating the smallest chitosan particles, the TF-2 enriched black tea extract was added to the chitosan-acetic acid solution to be electrosprayed. The particles were assessed with the following procedures: Atomic force microscopy (AFM) and scanning electron microscopy (SEM) for particle morphology and size, and loading efficiency with ultraviolet--visible spectrophotometer (UV-VIS). Chitosan-BTE nanoparticles were successfully created in a one step process. Diameter of the particles on average

Development and application of UHPLC-MS/MS method for the determination of phenolic compounds in Chamomile flowers and Chamomile tea extracts.

PubMed

Nováková, Lucie; Vildová, Anna; Mateus, Joana Patricia; Gonçalves, Tiago; Solich, Petr

2010-09-15

UHPLC-MS/MS method using BEH C18 analytical column was developed for the separation and quantitation of 12 phenolic compounds of Chamomile (Matricaria recutita L.). The separation was accomplished using gradient elution with mobile phase consisting of methanol and formic acid 0.1%. ESI in both positive and negative ion mode was optimized with the aim to reach high sensitivity and selectivity for quantitation using SRM experiment. ESI in negative ion mode was found to be more convenient for quantitative analysis of all phenolics except of chlorogenic acid and kaempherol, which demonstrated better results of linearity, accuracy and precision in ESI positive ion mode. The results of method validation confirmed, that developed UHPLC-MS/MS method was convenient and reliable for the determination of phenolic compounds in Chamomile extracts with linearity >0.9982, accuracy within 76.7-126.7% and precision within 2.2-12.7% at three spiked concentration levels. Method sensitivity expressed as LOQ was typically 5-20 nmol/l. Extracts of Chamomile flowers and Chamomile tea were subjected to UHPLC-MS/MS analysis. The most abundant phenolic compounds in both Chamomile flowers and Chamomile tea extracts were chlorogenic acid, umbelliferone, apigenin and apigenin-7-glucoside. In Chamomile tea extracts there was greater abundance of flavonoid glycosides such as rutin or quercitrin, while the aglycone apigenin and its glycoside were present in lower amount. Copyright (c) 2010 Elsevier B.V. All rights reserved.

[Chemical and sensory characterization of tea (Thea sinensis) consumed in Chile].

PubMed

Wittig de Penna, Emma; José Zúñiga, María; Fuenzalida, Regina; López-Planes, Reinaldo

2005-03-01

By means of descriptive analysis four varieties of tea (Thea sinensis) were assesed: Argentinean OP (orange pekoe) tea (black), Brazilian OP tea (black), Ceylan OP tea (black) and Darjeeling OP tea (green). The appearance of dry tea leaves were qualitatively characterized comparing with dry leaves standard. The attributes: colour, form, regularity of the leaves, fibre and stem cutting were evaluated The differences obtained were related to the differences produced by the effect of the fermentation process. Flavour and aroma descriptors of the tea liqueur were generated by a trained panel. Colour and astringency were evaluated in comparison with qualified standards using non structured linear scales. In order to relate the sensory analysis and the chemical composition for the different varieties of tea, following determinations were made: chemical moisture, dry material, aqueous extract, tannin and caffeine. Through multifactor regression analysis the equations in relation to the following chemical parameters were determined. Dry material, aqueous extract and tannins for colour and moisture, dry material and aqueous extract for astringency, respectively. Statistical analysis through ANOVA (3 variation sources: samples, judges and replications) showed for samples four significant different groups for astringency and three different groups for colour. No significant differences between judges or repetitions were found. By multifactor regression analysis of both, colour and astringency, on their dependence of chemist results were calculated in order to asses the corresponding equations.

Analysis of biologically active oxyprenylated phenylpropanoids in Tea tree oil using selective solid-phase extraction with UHPLC-PDA detection.

PubMed

Scotti, Luca; Genovese, Salvatore; Bucciarelli, Tonino; Martini, Filippo; Epifano, Francesco; Fiorito, Serena; Preziuso, Francesca; Taddeo, Vito Alessandro

2018-05-30

An efficient analytical strategy based on different extraction methods of biologically active naturally occurring oxyprenylated umbelliferone and ferulic acid derivatives 7-isopentenyloxycoumarin, auraptene, umbelliprenin, boropinic acid, and 4'-geranyloxyferulic acid and quantification by UHPLC with spectrophotometric (UV/Vis) detection from Tea tree oil is reported. Absorption of the pure oil on Al 2 O 3 (Brockmann activity II) prior washing the resulting solid with MeOH and treatment of this latter with CH 2 Cl 2 resulted the best extraction methodology in terms of yields of oxyprenylated secondary metabolites. Among the five O-prenylphenylpropanoids herein under investigation auraptene and umbelliprenin were never detected while 4'-geranyloxyferulic acid was the most abundant compound resulting from all the three extraction methods employed. The UHPLC analytical methodology set up in the present study resulted to be an effective and versatile technique for the simultaneous characterization and quantification of prenyloxyphenylpropanoids in Tea tree oil and applicable to other complex matrices from the plant kingdom. Copyright © 2018 Elsevier B.V. All rights reserved.

Comparison of two thin-film microextractions for the analysis of estrogens in aqueous tea extract and environmental water samples by high performance liquid chromatography-ultraviolet detection.

PubMed

Cai, Pei-Shan; Li, Dan; Chen, Jing; Xiong, Chao-Mei; Ruan, Jin-Lan

2015-04-15

Two thin-film microextractions (TFME), octadecylsilane (ODS)-polyacrylonitrile (PAN)-TFME and polar enhanced phase (PEP)-PAN-TFME have been proposed for the analysis of bisphenol-A, diethylstilbestrol and 17β-estradiol in aqueous tea extract and environmental water samples followed by high performance liquid chromatography-ultraviolet detection. Both thin-films were prepared by spraying. The influencing factors including pH, extraction time, desorption solvent, desorption volume, desorption time, ion strength and reusability were investigated. Under the optimal conditions, the two TFME methods are similar in terms of the analytical performance evaluated by standard addition method. The limits of detection for three estrogens in environmental water and aqueous tea extract matrix ranged from 1.3 to 1.6 and 2.8 to 7.1 ng mL(-1) by the two TFME methods, respectively. Both approaches were applied for the analysis of analytes in real aqueous tea extract and environmental water samples, presenting satisfactory recoveries ranged from 87.3% to 109.4% for the spiked samples. Copyright © 2014 Elsevier Ltd. All rights reserved.

Obtaining of caffeine from Turkish tea fiber and stalk wastes.

PubMed

Gürü, M; Içen, H

2004-08-01

The aim of this study was to find a cheap method to obtain caffeine. Experiments were performed on fiber and stalk wastes of Turkish tea plants that had no economical value other than being used merely as low grade fuel and fodder. Tea stalks and fiber were obtained from tea factories. Parameters affecting caffeine extraction from tea wastes were determined to be, mixing rate, water/tea ratio, temperature, time and particle size. The maximum yields by dried mass from the tea fibers and stalks were 1.16% and 0.92%, respectively.

Antioxidant and potential anti-inflammatory activity of extracts and formulations of white tea, rose, and witch hazel on primary human dermal fibroblast cells

PubMed Central

2011-01-01

Background Numerous reports have identified therapeutic roles for plants and their extracts and constituents. The aim of this study was to assess the efficacies of three plant extracts for their potential antioxidant and anti-inflammatory activity in primary human skin fibroblasts. Methods Aqueous extracts and formulations of white tea, witch hazel and rose were subjected to assays to measure anti-collagenase, anti-elastase, trolox equivalent and catalase activities. Skin fibroblast cells were employed to determine the effect of each extract/formulation on IL-8 release induced by the addition of hydrogen peroxide. Microscopic examination along with Neutral Red viability testing was employed to ascertain the effects of hydrogen peroxide directly on cell viability. Results Considerable anti-collagenase, anti-elastase, and antioxidant activities were measured for all extracts apart from the witch hazel distillate which showed no activity in the collagenase assay or in the trolox equivalence assay. All of the extracts and products tested elicited a significant decrease in the amount of IL-8 produced by fibroblast cells compared to the control (p < 0.05). None of the test samples exhibited catalase activity or had a significant effect on the spontaneous secretion of IL-8 in the control cells which was further corroborated with the microscopy results and the Neutral Red viability test. Conclusions These data show that the extracts and products tested have a protective effect on fibroblast cells against hydrogen peroxide induced damage. This approach provides a potential method to evaluate the claims made for plant extracts and the products in which these extracts are found. PMID:21995704

Oxidation Stability of Pig Liver Pâté with Increasing Levels of Natural Antioxidants (Grape and Tea)

PubMed Central

Pateiro, Mirian; Lorenzo, José M.; Vázquez, José A.; Franco, Daniel

2015-01-01

The present study investigated the effect of the addition of increasing levels of the natural antioxidants tea (TEA) and grape seed extracts (GRA) on the physiochemical and oxidative stability of refrigerated stored pig pâtés. In addition, a synthetic antioxidant and a control batch were used, thus a total of eight batches of liver pâté were prepared: CON, BHT, TEA (TEA50, TEA200 and TEA1000) and GRA (GRA50, GRA200 and GRA1000). Pâté samples were analyzed following 0, 4, 8 and 24 weeks of storage. Color parameters were affected by storage period and level of antioxidant extract. Samples with TEA200 and GRA1000 levels of extracts showed lower total color difference between 0 and 24 weeks. At the end of storage period, the lower TBARs values were obtained in samples with the highest concentration on natural extract. Overall, the evolution of volatile compounds showed an increase in those ones that arise from the lipid oxidation and samples with TEA1000 extract showed the lowest values. PMID:26785340

Tea and Cardiovascular Disease

PubMed Central

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

The Activity Test of Ethanol Extract Tea Parasite Herb (Scurrulla Artopurpurea) as an Immunostimulator on Wistar Strain Rat Sensititized with Sheep Red Blood Cell

NASA Astrophysics Data System (ADS)

Yulianti, Retno; Dimas A, M.; Hafiz, Aldi; Amalia, Muttia

2018-03-01

Tea parasite (Scurrulla artropurpurea) is one of the hemiparasite plants suspected as an imustimulator agent. The aims of this study was to prove the activity of tea parasite herb extract as immunostimulator in Wistar strain rats that are sensitized by sheep red blood cell suspension (SRBC). Twenty eight Wistar rats were divided into 4 groups. The control group was given CMC 1%, the treatment group was given the tea parasite herb extract at doses of 750 mg, 1.5g and 3 g/kgBW/day, each group was sensitized by SRBC 10% as much 0.5 ml intraperitoneally on the 0th and 9th days and 0.1 ml intraplantar on 12th days. The total number of leukocyte and lymphocyte cells was performed using blood smear and analyzed by GLMRM. test. The macrophage cell activity and the capacity of the peritoneal fluid preparation on day 14 and analyzed by ANOVA test. The histopathological features are demonstrated after 48 hours of intraplantar injection, quantitatively perceived perivascular and periadnexal infiltrates. The results showed that there were average differences on leukocyte cell counts (F = 46.249) and total lymphocyte cells (F = 58.144) on each calculation (day), but there were no average differences between each treatment group. The highest activity of phagocytosis is 78% and continues to increase along with the additional dose of extract, without the increased capacity of macrophage phagocytosis. Histopathological features of slow-type IV reaction shows mild severity. It can be concluded that the active compound of the extract tea parasite herbare able to improve immune system.

Determination of five pyrethroids in tea drinks by dispersive solid phase extraction with polyaniline-coated magnetic particles.

PubMed

Wang, Yuanpeng; Sun, Ying; Gao, Yan; Xu, Bo; Wu, Qiong; Zhang, Hanqi; Song, Daqian

2014-02-01

The polyaniline-coated magnetic particles with bowl-shaped morphology (Fe3O4/C/PANI microbowls) were successfully prepared and characterized by scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometry. The prepared microbowls were used as the magnetic adsorbent in dispersive solid phase extraction of five pyrethroids, including cyhalothrin, beta-cypermethrin, esfenvalerate, permethrin and bifenthrin in plain tea drinks. The effects of experiment factors, including amount of Fe3O4/C/PANI microbowls, pH value, ultrasound extraction time and desorption conditions, were investigated. The extraction recoveries obtained with 8 mg of magnetic microbowls were satisfactory, and the microbowls can be reused after easy washing. Thus, a simple, selective and effective method for the determination of the pyrethroids was established successfully. The results showed that the method had good linearity (r=0.9992-0.9998), and the limits of detections (LODs) were from 0.025 to 0.032 ng mL(-1). The intra-day and inter-day relative standard deviations (RSDs) were in the range of 2.4-6.1% and 3.5-8.8%, respectively. Recoveries obtained by analyzing the real tea drinks were in the range of 72.1-118.4%. © 2013 Published by Elsevier B.V.

The effect of green tea and olive oil on the mutagenic activity of heterocyclic amines extracted from common food consumed in Saudi Arabia.

PubMed

Awney, Hala

2011-05-01

The effect of green tea (GT) and green tea with olive oil (GT+OL) as antioxidants on the formation and mutagenic activity of heterocyclic aromatic amines (HCAs) extracted from beef shawerma, grilled chicken and fried beef liver was examined. HCAs were extracted by blue rayon, analyzed as spiked and unspiked samples with high-performance liquid chromatography and its mutagenic response was assessed by Sallmonela typhimurium 100 in the Ames test. Surprisingly, GT and GT+OL augmented HCAs measured in beef shawerma and grilled chicken but total HCAs measured in GT+OL were less than GT treatment. Both treatments altered the HCA profile as imidazoquinoline type became the most abundant. In control and GT+OL fried beef liver no HCAs were detected, but Trp-P1 was detected in GT treatment. Generally, the mutagenic response of HCAs measured in GT+OL was less than GT in beef shawerma and grilled chicken. However, the mutagenic response of control and 2% GT+OL fried liver was negative. These data suggest that GT concentrations used in this study may induce free radical formation during the Millared reaction due to its pro-oxidative effect, which augmented the HCAs formed and its mutagenic response. In order to optimize both safety and quality of our diets, more need to be done to fully understand the risk of HCAs in food.

In vitro and in vivo anti-allergic effects of ‘benifuuki’ green tea containing O-methylated catechin and ginger extract enhancement

PubMed Central

Ema, Kaori; Shibuichi, Ikuo

2007-01-01

‘Benifuuki’, a tea (Camellia Sinensis L.) cultivar in Japan, is rich in anti-allergic epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3″Me). ‘Benifuuki’ green tea and simultaneous addition of ginger extract remarkably suppressed cytokine (TNF-α and MIP-1α) secretion from mouse bone marrow-derived mast cells after antigen stimulation and, as expected, suppressed delay-type allergy. After drinking ‘benifuuki’ green tea containing 43.5 mg of EGCG and 8.5 mg of EGCG3″Me, the AUC (area under the drug concentration time curve; min μg/ml) of EGCG was 6.72 ± 2.87 and EGCG3″Me was 8.48 ± 2.54 in healthy human volunteers. Though the dose of EGCG was 5.1 times the dose of EGCG3″Me, the AUC of EGCG3″Me was higher than that of EGCG. A double blind clinical study on subjects with Japanese cedar pollinosis was carried out. At the 11th week after starting the study, in the most severe cedar pollen scattering period, symptoms, i.e., blowing the nose and itching eyes, were significantly relieved in the ‘benifuuki’ intake group compared with the placebo group, and blowing the nose, itching eyes and nasal symptom score, and at the 11th and 13th weeks, stuffy nose, throat pain and the nasal symptom medication score were significantly relieved in the ‘benifuuki’ containing ginger extract group compared with the placebo group. These results suggested that over one consecutive month, drinking ‘benifuuki’ green tea was useful to reduce some of the symptoms from Japanese cedar pollinosis, and did not affect any normal immune response in subjects with seasonal rhinitis, and the ginger extract enhanced the effect of ‘benifuuki’ green tea. PMID:19003003

A Randomized, Double-blind, Placebo-controlled Clinical Trial Examining the Effects of Green Tea Extract on Systemic Lupus Erythematosus Disease Activity and Quality of Life.

PubMed

Shamekhi, Z; Amani, R; Habibagahi, Z; Namjoyan, F; Ghadiri, Ata; Saki Malehi, A

2017-07-01

Antiinflammatory and immunomodulatory benefit of green tea (Camellia sinensis) in autoimmune disease has been proven in recent studies. The objective of this study was to assess the effects of green tea on disease activity and quality of life in systemic lupus erythematosus patients. A randomized controlled trial on subjects with lupus was conducted, and 68 patients in the age range of 39.1 ± 10.3 years and body mass index of 25.7 ± 5.21 kg/m 2 completed the 12-week study. Patients were randomly divided into two groups of intervention (1000 mg green tea extract, two capsules/day) and control (1000 mg of starch, two capsules/day). Main outcome measure, systemic lupus erythematosus disease activity, was assessed by the systemic lupus erythematosus disease activity index at the first and after 3 months of intervention. In addition, patient's quality of life was evaluated by short form of quality-of-life questionnaire at baseline and after 3 months. Green tea extract supplementation significantly reduced disease activity in lupus patients (p < 0.004); in addition, it significantly increased the vitality (p < 0.006) and general health (p < 0.01). This study showed that daily consumption of green tea extracts for 12 weeks improves the systemic lupus erythematosus disease activity as well as some aspects of quality of life. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Green tea supplementation affects body weight, lipids, and lipid peroxidation in obese subjects with metabolic syndrome.

PubMed

Basu, Arpita; Sanchez, Karah; Leyva, Misti J; Wu, Mingyuan; Betts, Nancy M; Aston, Christopher E; Lyons, Timothy J

2010-02-01

To compare the effects of supplementation of green tea beverage or green tea extracts with controls on body weight, glucose and lipid profile, biomarkers of oxidative stress, and safety parameters in obese subjects with metabolic syndrome. Randomized, controlled prospective trial. General Clinical Research Center (GCRC) at University of Oklahoma Health Sciences Center (OUHSC). Thirty-five subjects with obesity and metabolic syndrome were recruited in age- and gender-matched trios and were randomly assigned to the control (4 cups water/d), green tea (4 cups/d), or green tea extract (2 capsules and 4 cups water/d) group for 8 weeks. The tea and extract groups had similar dosing of epiogallocatechin-3-gallate (EGCG), the active compound in green tea. Anthropometrics, blood pressure, fasting glucose and lipids, nuclear magnetic resonance (NMR)-based lipid particle size, safety parameters, biomarkers of oxidative stress (oxidized low-density lipoprotein [LDL], myeloperoxidase [MPO], malondialdehyde and hydroxynonenals [MDA and HNE]), and free catechins were analyzed at screen and at 4 and 8 weeks of the study. Pairwise comparisons showed green tea beverage and green tea extracts caused a significant decrease in body weight and body mass index (BMI) versus controls at 8 weeks (-2.5 +/- 0.7 kg, p < 0.01, and -1.9 +/- 0.6, p < 0.05, respectively). Green tea beverage showed a decreasing trend in LDL-cholesterol and LDL/high-density lipoprotein (HDL) versus controls (p < 0.1). Green tea beverage also significantly decreased MDA and HNE (-0.39 +/- 0.06 microM, p < 0.0001) versus controls. Plasma free catechins were detectable in both beverage and extract groups versus controls at screen and at 8 weeks, indicating compliance and bioavailability of green tea catechins. Green tea beverage consumption (4 cups/d) or extract supplementation (2 capsules/d) for 8 weeks significantly decreased body weight and BMI. Green tea beverage further lowered lipid peroxidation versus age- and

Design, formulation and evaluation of green tea chewing gum

PubMed Central

Aslani, Abolfazl; Ghannadi, Alireza; Khalafi, Zeinab

2014-01-01

Background: The main purpose of this study is to design, formulate and evaluate the green tea gums with a suitable taste and quality in order to produce an anti-oxidant chewing gum. Materials and Methods: Fresh green tea leaves obtained from Northern Iran for extraction. Maceration is the extraction method that is used in this study. The contents of caffeine, catechin and flavonoids of the hydro alcoholic extract were measured. Various formulations of the 120 mg green tea extract chewing gums with different sweeteners, flavoring agents and various gum bases were prepared afterward release pattern, content uniformity, organoleptic results and other properties were characterized. Results: The contents of caffeine, catechin and flavonoid of the hydro alcoholic extraction were 207.32 mg/g, 130.00 mg/g and 200.82 mg/g, respectively. Release pattern of green tea chewing gum with different gum base ratios and various sweeteners in phosphate buffer were prepared. A total of 60 persons who were 20-30 years of age, participated in our panel test for organoleptic properties such as taste, stiffness, stickiness, etc., Acceptable gum was the one with the same ratio of the used rubber bases. Cinnamon selected as the preferred taste by volunteers. Combination of aspartame, sugar and maltitol has appropriate taste. The effect of various sweetener on release pattern was negligible, on the other hand rubber bases ratio variation, changed the release pattern obviously. Conclusion: The green tea chewing gum with sugar, maltitol and aspartame sweeteners and cinnamon flavor, using the same rubber bases ratio may be a desirable antioxidant product. PMID:25161989

Simultaneous analysis of tropane alkaloids in teas and herbal teas by liquid chromatography coupled to high-resolution mass spectrometry (Orbitrap).

PubMed

Romera-Torres, Ana; Romero-González, Roberto; Martínez Vidal, José Luis; Garrido Frenich, Antonia

2018-05-01

A new method has been developed for the simultaneous determination of 13 tropane alkaloids in tea and herbal teas using high-performance liquid chromatography coupled to an Exactive-Orbitrap analyzer. A mixture of methanol, water, and formic acid was used for the extraction of the target compounds followed by a solid-phase extraction step. The validated method provided recoveries from 75 to 128% with intra- and interday precision lower than or equal to 24% (except for apoatropine). Limits of quantification ranged from 5 to 20 μg/kg. Eleven tea and herbal tea samples and two contaminated samples with Datura stramonium seeds were analyzed. Tropane alkaloids were detected in six samples with concentrations from 5 (apoatropine) to 4340 μg/kg (sum of physoperuvine, pseudotropine, and tropine), whereas concentrations from 5 (apoatropine) to 1725 μg/kg (sum of physoperuvine, pseudotropine, and tropine) were found in the contaminated samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phytochemical analysis of the triterpenoids with cytotoxicity and QR inducing properties from the total tea seed saponin of Camellia sinensis.

PubMed

Li, Ning; Ma, Zhong-Jun; Chu, Yang; Wang, Ying; Li, Xian

2013-01-01

The tea seed triterpene saponin (TS) from Camellia sinensis was found to exhibit better antitumor activity in vivo in S180 implanted ICR mice and QR inducing activity for hepa lclc7 cells respectively compared with the total tea seed saponin (TTS), hydrolysate of the TTS and tea seed flavonoid glycosides (TF). By bioassay-guided isolation, the TS fraction was separated and seven major components were purified and identified as theasaponin E1 (1), theasaponin E2 (2), theasaponin C1 (3), assamsaponin C (4), theasaponin H1 (5), theasaponin A9 (6), and theasaponin A8 (7), among which compounds 4 and 5 were isolated from this genus for the first time. The antitumor bioassay of the isolated compounds showed that compounds 1, 2 and 3 exhibited potential activities against the human tumor cell lines K562 and HL60. Furthermore, compound 1 (the major constituent with a mass content of over 1%) showed significant QR inducing activity with an IR value of 4.2 at 4μg/ml. So it can be concluded that tea seed especially the compound 1 (theasaponin E1) could be used as an antitumor agent and a chemoprevention agent of cancer. The preliminary structure-activity relationship in the anti-tumor activity and QR inducing activity of tea saponins was discussed briefly. Copyright © 2012 Elsevier B.V. All rights reserved.

Therapeutic effect of high-dose green tea extract on weight reduction: A randomized, double-blind, placebo-controlled clinical trial.

PubMed

Chen, I-Ju; Liu, Chia-Yu; Chiu, Jung-Peng; Hsu, Chung-Hua

2016-06-01

To examine the effect and safety of high-dose green tea extract (Epigallocatechin gallate, EGCG) at a daily dosage of 856.8 mg on weight reduction and changes of lipid profile and obesity-related hormone peptides in women with central obesity. We conducted a randomized, double-blind trial registered under ClinicalTrials.gov Identifier no. NCT02147041. A total of 115 women with central obesity were screened at our clinic. 102 of them with a body mass index (BMI) ≥ 27 kg/m(2) and a waist circumference (WC) ≥ 80 cm were eligible for the study. These women were randomly assigned to either a high-dose green tea group or placebo group. The total treatment time was 12 weeks. The main outcome measures were anthropometric measurements, lipid profiles, and obesity related hormone peptides including leptin, adiponectin, ghrelin, and insulin. Significant weight loss, from 76.8 ± 11.3 kg to 75.7 ± 11.5 kg (p = 0.025), as well as decreases in BMI (p = 0.018) and waist circumference (p = 0.023) were observed in the treatment group after 12 weeks of high-dose EGCG treatment. This study also demonstrated a consistent trend of decreased total cholesterol, reaching 5.33%, and decreased LDL plasma levels. There was good tolerance of the treatment among subjects without any side effects or adverse events. Significantly lower ghrelin levels and elevated adiponectin levels were detected in the study group than in the placebo group. 12 weeks of treatment with high-dose green tea extract resulted in significant weight loss, reduced waist circumference, and a consistent decrease in total cholesterol and LDL plasma levels without any side effects or adverse effects in women with central obesity. The antiobestic mechanism of high-dose green tea extract might be associated in part with ghrelin secretion inhibition, leading to increased adiponectin levels. Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Conney, Allan H.; Zhou, Sherry; Lee Maojung

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.more » 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.« less

Protective effects of dietary chamomile tea on diabetic complications.

PubMed

Kato, Atsushi; Minoshima, Yuka; Yamamoto, Jo; Adachi, Isao; Watson, Alison A; Nash, Robert J

2008-09-10

Matricaria chamomilla L., known as "chamomile", has been used as an herbal tea or supplementary food all over the world. We investigated the effects of chamomile hot water extract and its major components on the prevention of hyperglycemia and the protection or improvement of diabetic complications in diabetes mellitus. Hot water extract, esculetin (3) and quercetin (7) have been found to show moderate inhibition of sucrase with IC50 values of 0.9 mg/mL and 72 and 71 microM, respectively. In a sucrose-loading test, the administration of esculetin (50 mg/kg body weight) fully suppressed hyperglycemia after 15 and 30 min, but the extract (500 mg/kg body weight) and quercetin (50 mg/kg body weight) were less effective. On the other hand, a long-term feed test (21 days) using a streptozotocin-induced rat diabetes model revealed that the same doses of extract and quercetin showed significant suppression of blood glucose levels. It was also found that these samples increased the liver glycogen levels. Moreover, chamomile extract showed potent inhibition against aldose reductase (ALR2), with an IC50 value of 16.9 microg/mL, and its components, umbelliferone (1), esculetin (3), luteolin (6), and quercetin (7), could significantly inhibit the accumulation of sorbitol in human erythrocytes. These results clearly suggested that daily consumption of chamomile tea with meals could contribute to the prevention of the progress of hyperglycemia and diabetic complications.

Green tea: a promising natural product in oral health.

PubMed

Narotzki, Baruch; Reznick, Abraham Z; Aizenbud, Dror; Levy, Yishai

2012-05-01

Green tea is a leading beverage in the Far East for thousands of years; it is regarded for a long time as a health product. Green tea is important source of polyphenol antioxidants. Polyphenols including epigallocatechin 3 gallate (EGCG) constitute the most interesting components in green tea leaves. Green tea has the potential to protect against various malignant, cardiovascular and metabolic diseases. There is a growing body of evidence pointing a beneficial role of green tea and its polyphenols in oral health. Green tea protects against bacterial induced dental caries. Tea polyphenols possess antiviral properties, believed to help in protection from influenza virus. Additionally, green tea polyphenols can abolish halitosis through modification of odorant sulphur components. Oral cavity oxidative stress and inflammation, consequent to cigarette smoking and cigarettes' deleterious compounds nicotine and acrolein, may be reduced in the presence of green tea polyphenols. Generally, green tea defends healthy cells from malignant transformation and locally has the ability to induce apoptosis in oral cancer cells. All together, there is an increasing interest in the health benefits of green tea in the field of oral health. Nonetheless, there is still a need for more clinical and biological studies to support guidelines for green tea intake as part of prevention and treatment of specific oral pathologies. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of green tea extract as a safe personal hygiene against viral infections.

PubMed

Lee, Yun Ha; Jang, Yo Han; Kim, Young-Seok; Kim, Jinku; Seong, Baik Lin

2018-01-01

Viral infections often pose tremendous public health concerns as well as economic burdens. Despite the availability of vaccines or antiviral drugs, personal hygiene is considered as effective means as the first-hand measure against viral infections. The green tea catechins, in particular, epigallocatechin-3-gallate (EGCG), are known to exert potent antiviral activity. In this study, we evaluated the green tea extract as a safe personal hygiene against viral infections. Using the influenza virus A/Puerto Rico/8/34 (H1N1) as a model, we examined the duration of the viral inactivating activity of green tea extract (GTE) under prolonged storage at various temperature conditions. Even after the storage for 56 days at different temperatures, 0.1% GTE completely inactivated 10 6 PFU of the virus (6 log 10 reduction), and 0.01% and 0.05% GTE resulted in 2 log 10 reduction of the viral titers. When supplemented with 2% citric acid, 0.1% sodium benzoate, and 0.2% ascorbic acid as anti-oxidant, the inactivating activity of GTE was temporarily compromised during earlier times of storage. However, the antiviral activity of the GTE was steadily recovered up to similar levels with those of the same concentrations of GTE without the supplements, effectively prolonging the duration of the virucidal function over extended period. Cryo-EM and DLS analyses showed a slight increase in the overall size of virus particles by GTE treatment. The results suggest that the virucidal activity of GTE is mediated by oxidative crosslinking of catechins to the viral proteins and the change of physical properties of viral membranes. The durability of antiviral effects of GTE was examined as solution type and powder types over extended periods at various temperature conditions using human influenza A/H1N1 virus. GTE with supplements demonstrated potent viral inactivating activity, resulting in greater than 4 log 10 reduction of viral titers even after storage for up to two months at a wide range of

Impact of green tea extract addition on oxidative changes in the lipid fraction of pastry products.

PubMed

Żbikowska, Anna; Kowalska, Małgorzata; Rutkowska, Jarosława; Kozłowska, Mariola; Onacik-Gür, Sylwia

2017-01-01

Alongside flour, fat is the key ingredient of sponge cakes, including those with long shelf lives. It is an unstable food component, whose quality and nutritional safety depend on the composition and pres- ence of oxidation products. Consumption of fat oxidation products adversely affects the human body and contributes to the incidence of a number of medical conditions. Qualitative changes in fats extracted from thermostat sponge cakes with and without antioxidant additions were determined in this study. In the study, two types of antioxidant were used: natural - green tea extract in three doses (0.02%; 0.2% and 1.0%) and synthetic BHA (0.02%) and 100%, solid bakery shortening. Sponge-cakes were thermostatted at temperatures 63°C after twenty-eight days. In this study, the quality of the lipid fraction was analyzed. The amount of primary (PV) and secondary (AnV) oxidation products was determined, and   a Rancimat test was performed. Adding antioxidants to fats varied in the degree to which oxidation processes of lipids fractions were inhibited. The peroxide value after twenty-eight days of thermostatting ranged from 3.57 meq O/kg (BHA) and 11.14 O meq/kg (extract content - 1%) to 62.85 meq O/kg (control sample). In turn, the value of AnV after the storage period ranged from 4.84 (BHA) and 6.71 (extract content - 1%) to 16.83 (control sample). The best protective effects in the process of oxidation was achieved by BHA. The longest in- duction time and the lowest peroxide value and anisidine value were obtained for this antioxidant. It was achieved after twenty-eight days of fat thermostatting. Nonetheless, the results demonstrated it is possible to use the commercially available green tea extract to slow the adverse process of fat oxidation in sponge cake products.

Pu-erh Tea Reduces Nitric Oxide Levels in Rats by Inhibiting Inducible Nitric Oxide Synthase Expression through Toll-Like Receptor 4

PubMed Central

Xu, Yang; Wang, Guan; Li, Chunjie; Zhang, Min; Zhao, Hang; Sheng, Jun; Shi, Wei

2012-01-01

Pu-erh tea undergoes a unique fermentation process and contains theabrownins, polysaccharides and caffeine; although it is unclear about which component is associated with the down regulation of nitric oxide levels or how this process is mediated. To address this question we examined the effects of pu-erh tea on nitric oxide synthase (NOS) genes. Cohorts of rats were separately given four-week treatments of water as control, pu-erh tea, or the tea components: theabrownins, caffeine or polysaccharides. Five experimental groups were injected with lipopolysaccharides (LPS) to induce nitric oxide (NO) production, while the corresponding five control groups were injected with saline as a negative control. The serum and liver NO concentrations were examined and the NOS expression of both mRNA and protein was measured in liver. The results showed that the rats which were fed pu-erh tea or polysaccharides had lower levels of NO which corresponded with the down-regulation of inducible nitric oxide synthase (iNOS) expression. We further demonstrate that this effect is mediated through reduction of Toll-like receptor 4 (TLR4) signaling. Thus we find that the polysaccharide components in pu-erh tea reduce NO levels in an animal model by inhibiting the iNOS expression via signaling through TLR4. PMID:22837686

A randomized controlled trial of green tea catechins in protection against ultraviolet radiation-induced cutaneous inflammation.

PubMed

Farrar, Mark D; Nicolaou, Anna; Clarke, Kayleigh A; Mason, Sarah; Massey, Karen A; Dew, Tristan P; Watson, Rachel E B; Williamson, Gary; Rhodes, Lesley E

2015-09-01

Safe systemic protection from the health hazards of ultraviolet radiation (UVR) in sunlight is desirable. Green tea is consumed globally and is reported to have anti-inflammatory properties, which may be mediated through the impact on cyclooxygenase and lipoxygenase pathways. Recent data suggest that green tea catechins (GTCs) reduce acute UVR effects, but human trials examining their photoprotective potential are scarce. We performed a double-blind, randomized, placebo-controlled trial to examine whether GTCs protect against clinical, histologic, and biochemical indicators of UVR-induced inflammation. Healthy adults (aged 18-65 y, phototypes I-II) were randomly allocated to 1350 mg encapsulated green tea extract (540 mg GTC) with 50 mg vitamin C or placebo twice daily for 3 mo. Impact on skin erythema, dermal leukocytic infiltration, and concentrations of proinflammatory eicosanoids was assessed after solar-simulated UVR challenge, and subject compliance was determined through assay of urinary GTC metabolite epigallocatechin glucuronide. Volunteers were assigned to the active (n = 25) or the placebo (n = 25) group. After supplementation, median (IQR) sunburn threshold (minimal erythema dose) was 28 (20-28) and 20 (20-28) mJ/cm(2) in the active and placebo groups, respectively (nonsignificant), with no difference in AUC analysis for measured erythema index after a geometric series of 10 UVR doses. Skin immunohistochemistry showed increased neutrophil and CD3(+) T-lymphocyte numbers post-UVR in both groups (P < 0.01) with no statistically significant differences between groups after supplementation. Cyclooxygenase and lipoxygenase metabolites prostaglandin E2 (vasodilator) and 12-hydroxyeicosatetraenoicacid (chemoattractant), respectively, increased after UVR (P < 0.05), with no differences between supplementation groups. Oral GTC (1080 mg/d) with vitamin C over 3 mo did not significantly reduce skin erythema, leukocyte infiltration, or eicosanoid response to UVR

Beneficial effects of cocoa, coffee, green tea, and garcinia complex supplement on diet induced obesity in rats.

PubMed

Huang, Chi-Chang; Tung, Yu-Tang; Huang, Wen-Ching; Chen, Yi-Ming; Hsu, Yi-Ju; Hsu, Mei-Chich

2016-03-12

Cocoa, coffee, green tea and garcinia contain large amounts of polyphenols. Polyphenols are well-known phytochemicals and found in plants, and have modulated physiological and molecular pathways that are involved in energy metabolism, adiposity, and obesity. To evaluate the obesity-lowering effect of a combined extract (comprising cocoa, coffee, green tea and garcinia; CCGG) in high-energy diet (HED)-induced obese rats. Male Sprague Dawley rats (8 weeks old) were randomly divided into four groups (n = 12 per group): normal diet with vehicle treatment (Control), and HED to receive vehicle or CCGG by oral gavage at 129, 258, or 517 mg/kg/day for 4 weeks, designated the HED, 0.5X, 1X and 1X groups, respectively. HED induced macrovesicular fat in the liver and the formation of adipose tissues, and significantly increased the levels of serum free fatty acids (FFA), triacylglycerol (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), and LDL-C/HDL-C, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and ketone bodies in serum, and hepatic TG and TC levels, and decreased the levels of high density lipoprotein cholesterol (HDL-C) in serum and lipase activity in fat tissues. Treatment with CCGG could significantly decrease the levels of FFA, TG, TC, LDL-C, and LDL-C/HDL-C, AST, ALT, and ketone bodies in serum, and hepatic TG and TC contents, and increase the levels of HDL-C in serum and lipase activity in fat tissues compared to the HED group. Liver histopathology also showed that CCGG could significantly reduce the incidence of liver lesions. These results suggested that CCGG stimulated lipid metabolism in HED-induced obese rats, which is attributable to fat mobilization from adipose tissue.

Microwave thawing and green tea extract efficiency for the formation of acrylamide throughout the production process of chicken burgers and chicken nuggets.

PubMed

Soncu, Eda Demirok; Kolsarici, Nuray

2017-04-01

Initially, we measured the acrylamide (AA) levels of chicken burgers (CBs) and chicken nuggets (CNs) purchased from fast food restaurants. After the determination of AA in these products, we aimed to investigate whether the use of green tea extract in the covering material, and microwave thawing before frying, mitigated the formation of AA in CBs and CNs during the production process. According to our study, AA concentrations of CBs and CNs purchased from fast food restaurants were in the range of 13.43-118.97 and 32.92-134.90 ng g -1 coating, respectively. In our experiment, AA levels varied between 19.61 and 40.08 ng g -1 coating for CBs and 7.92-49.60 ng g -1 coating for CNs. Green tea extract reduced the AA formation in CBs and CNs at the pan frying and steam oven cooking heat treatment steps (P < 0.05). However, microwave thawing did not affect AA level of CBs and CNs. When the AA levels of commercial CBs and CNs are compared with those produced in our experiment, the use of green tea extract could be a novel, easy and practical application for fast food producers to minimise AA levels in the first two steps of the production without changes to the sensory properties of the final products. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Sub-chronic indomethacin treatment and its effect on the male reproductive system of albino rats: possible protective role of black tea extract.

PubMed

Bagoji, Ishwar B; Hadimani, Gavishiddappa A; Yendigeri, Saeed M; Das, Kusal K

2017-05-01

Indomethacin is commonly used as a nonsteroidal anti-inflammatory drug (NSAID) to treat inflammation, arthritis and joint pains. Unfortunately, it has a wide range of adverse effects on the physiological system, including gonads. This study aimed to assess possible beneficial effects of black tea extract (BTE) against indomethacin-induced alteration of gonadal hormone levels in male rats. Adult male rats were divided into Group I (control), Group II (indomethacin, 5 mg/kg body weight [bwt.]; i.p., 21 days), Group III (BTE, 2.5 g tea leaf/dL of water, i.e. 2.5% of aqueous BTE, orally, 21 days) and Group IV (indomethacin+BTE, 21 days). Sperm count and motility, serum luteinising hormone (LH), follicle-stimulating hormone (FSH) and testosterone, along with histopathology of testes were studied. One-way ANOVA, followed by post-hoc t-test were conducted. Indomethacin-treated rats showed significant decrease in testicular weight, sperm count, sperm motility, serum gonadotropins and testosterone concentrations. Histopathology of the testes showed tortuous and distorted seminiferous tubules, marked thickening of the tubular basement membrane, reduced spermatogenesis process (>30%) and marked decrease in the number of interstitial cells of Leydig in indomethacin-treated rats. Interestingly, rats supplemented with BTE showed remarkable improvements in testicular weight gain, sperm count and motility, serum gonadotropins and testosterone concentrations, along with testicular histopathology. The results suggest that BTE might have potential ameliorative effects against sub-chronic indomethacin-induced alteration of gonadal hormone levels in male albino rats.

Chemical characterization of heteropolysaccharides from green and black teas (Camellia sinensis) and their anti-ulcer effect.

PubMed

Scoparo, Camila T; Souza, Lauro M; Dartora, Nessana; Sassaki, Guilherme L; Santana-Filho, Arquimedes P; Werner, Maria Fernanda P; Borato, Débora G; Baggio, Cristiane H; Iacomini, Marcello

2016-05-01

In order to obtain polysaccharides from green and black teas (Camellia sinensis), commercial leaves were submitted to infusion and then to alkaline extraction. The extracts were fractionated by freeze-thawing process, giving insoluble and soluble fractions. Complex arabinogalactan protein from the soluble fractions of both teas (GTPS and BTPS) were determined by methylation analysis and (1)H/(13)C-HSQC spectroscopy, showing a main chain of (1→3)-β-Galp, substituted at O-6 by (1→6)-linked β-Galp with side chains of α-Araf and terminal units of α-Araf, α-Fucp and α-Rhap. A highly branched heteroxylan from the insoluble fractions (GTPI and BTPI) showed in methylation analysis and (1)H/(13)C-HSQC spectroscopy the main chain of (1→4)-β-Xylp, substituted in O-3 by α-Araf, β-Galp and α-Glcp units. Evaluating their gastroprotective activity, the fractions containing the soluble heteropolysaccharides from green (GTPS) and black teas (BTPS) reduced the gastric lesions induced by ethanol. Furthermore, the fraction of insoluble heteropolysaccharides of green (GTPI) and black (BTPI) teas also protected the gastric mucosa. In addition, the maintenance of gastric mucus and reduced glutathione (GSH) levels was involved in the polysaccharides gastroprotection. Copyright © 2016 Elsevier B.V. All rights reserved.

Tea polysaccharide inhibits RANKL-induced osteoclastogenesis in RAW264.7 cells and ameliorates ovariectomy-induced osteoporosis in rats.

PubMed

Xu, Huanhuan; Yin, Dan; Liu, Titi; Chen, Fei; Chen, Yingli; Wang, Xuanjun; Sheng, Jun

2018-06-01

Tea drinking has positive effects on bone health and may prevent and treat osteoporosis, especially in older and postmenopausal women. Tea polysaccharide (TPS) is a major bioactive constituent in tea. Despite its profound effects on human health, whether TPS has anti-osteoporotic effects remains largely unknown. As such, we investigated the anti-osteoporotic effects of TPS. In vitro, TPS effects on osteoclastogenesis were examined using osteoclast precursor RAW264.7 cells. TPS effects on osteoclastogenesis-related expression of marker genes and proteins were determined by gene expression and immunoblotting analyses, respectively. For in vivo studies, 12-week-old female Wistar rats were divided randomly into a sham-operated group (sham) and four ovariectomized (OVX) subgroups: OVX with vehicle (model) and OVX with low-, medium-, and high-dose TPS (0.32, 0.64 and 1.28 g/kg body weight/day, respectively). TPS was administered intragastrically to rats for 13 weeks. Body weight, blood biochemical parameters, organ weight, organ coefficients, femoral length, bone mineral density (BMD), biomechanical properties, and bone microarchitecture were documented. TPS inhibited osteoclast differentiation significantly and dose-dependently, and its inhibitory effect was not due to toxicity to RAW264.7 cells. TPS suppressed expression of osteoclastogenesis-related marker genes and proteins significantly. In in vivo studies, medium-dose TPS treatment ameliorated OVX-induced calcium loss significantly. Low-dose TPS treatment decreased the activity of acid phosphatase (ACP) in OVX rats significantly. In addition, TPS treatment improved other blood biochemical parameters and femoral biomechanical properties to a certain extent. More importantly, TPS treatment ameliorated bone microarchitecture in OVX rats strikingly because of increased cortical bone thickness and trabecular bone area in the femur. TPS can inhibit receptor activator nuclear factor-kappa B ligand (RANKL)-induced

Green tea extract attenuates muscle loss and improves muscle function during disuse, but fails to improve muscle recovery following unloading in aged rats

PubMed Central

Bennett, Brian T.; Wilson, Joseph C.; Sperringer, Justin; Mohamed, Junaith S.; Edens, Neile K.; Pereira, Suzette L.

2014-01-01

In this study we tested the hypothesis that green tea extract (GTE) would improve muscle recovery after reloading following disuse. Aged (32 mo) Fischer 344 Brown Norway rats were randomly assigned to receive either 14 days of hindlimb suspension (HLS) or 14 days of HLS followed by normal ambulatory function for 14 days (recovery). Additional animals served as cage controls. The rats were given GTE (50 mg/kg body wt) or water (vehicle) by gavage 7 days before and throughout the experimental periods. Compared with vehicle treatment, GTE significantly attenuated the loss of hindlimb plantaris muscle mass (−24.8% vs. −10.7%, P < 0.05) and tetanic force (−43.7% vs. −25.9%, P <0.05) during HLS. Although GTE failed to further improve recovery of muscle function or mass compared with vehicle treatment, animals given green tea via gavage maintained the lower losses of muscle mass that were found during HLS (−25.2% vs. −16.0%, P < 0.05) and force (−45.7 vs. −34.4%, P < 0.05) after the reloading periods. In addition, compared with vehicle treatment, GTE attenuated muscle fiber cross-sectional area loss in both plantaris (−39.9% vs. −23.9%, P < 0.05) and soleus (−37.2% vs. −17.6%) muscles after HLS. This green tea-induced difference was not transient but was maintained over the reloading period for plantaris (−45.6% vs. −21.5%, P <0.05) and soleus muscle fiber cross-sectional area (−38.7% vs. −10.9%, P <0.05). GTE increased satellite cell proliferation and differentiation in plantaris and soleus muscles during recovery from HLS compared with vehicle-treated muscles and decreased oxidative stress and abundance of the Bcl-2-associated X protein (Bax), yet this did not further improve muscle recovery in reloaded muscles. These data suggest that muscle recovery following disuse in aging is complex. Although satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is

Green tea extract attenuates muscle loss and improves muscle function during disuse, but fails to improve muscle recovery following unloading in aged rats.

PubMed

Alway, Stephen E; Bennett, Brian T; Wilson, Joseph C; Sperringer, Justin; Mohamed, Junaith S; Edens, Neile K; Pereira, Suzette L

2015-02-01

In this study we tested the hypothesis that green tea extract (GTE) would improve muscle recovery after reloading following disuse. Aged (32 mo) Fischer 344 Brown Norway rats were randomly assigned to receive either 14 days of hindlimb suspension (HLS) or 14 days of HLS followed by normal ambulatory function for 14 days (recovery). Additional animals served as cage controls. The rats were given GTE (50 mg/kg body wt) or water (vehicle) by gavage 7 days before and throughout the experimental periods. Compared with vehicle treatment, GTE significantly attenuated the loss of hindlimb plantaris muscle mass (-24.8% vs. -10.7%, P < 0.05) and tetanic force (-43.7% vs. -25.9%, P <0.05) during HLS. Although GTE failed to further improve recovery of muscle function or mass compared with vehicle treatment, animals given green tea via gavage maintained the lower losses of muscle mass that were found during HLS (-25.2% vs. -16.0%, P < 0.05) and force (-45.7 vs. -34.4%, P < 0.05) after the reloading periods. In addition, compared with vehicle treatment, GTE attenuated muscle fiber cross-sectional area loss in both plantaris (-39.9% vs. -23.9%, P < 0.05) and soleus (-37.2% vs. -17.6%) muscles after HLS. This green tea-induced difference was not transient but was maintained over the reloading period for plantaris (-45.6% vs. -21.5%, P <0.05) and soleus muscle fiber cross-sectional area (-38.7% vs. -10.9%, P <0.05). GTE increased satellite cell proliferation and differentiation in plantaris and soleus muscles during recovery from HLS compared with vehicle-treated muscles and decreased oxidative stress and abundance of the Bcl-2-associated X protein (Bax), yet this did not further improve muscle recovery in reloaded muscles. These data suggest that muscle recovery following disuse in aging is complex. Although satellite cell proliferation and differentiation are critical for muscle repair to occur, green tea-induced changes in satellite cell number is by itself insufficient to

Tea, coffee, and cocoa as ultraviolet radiation protectants for the beet armyworm nucleopolyhedrovirus.

PubMed

El-Salamouny, S; Ranwala, D; Shapiro, M; Shepard, B M; Farrar, Robert R

2009-10-01

The addition of 1% (wt:vol) aqueous extracts of cocoa (Theobroma cacao L.) (Malvales: Malvaceae), coffee (Coffea arabica L.) (Gentianales: Rubiaceae), and green and black tea (Camellia sinensis L.) (Ericales: Theaceae) provided excellent UV radiation protection for the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae), nucleopolyhedrovirus under laboratory conditions. Aqueous extracts of coffee, green tea, and black tea at 0.5% provided 85-100% UV protection, whereas cocoa provided 50% UV protection. Epigallocatechin gallate (EGCG), a component of green tea, and caffeine, a component of tea and coffee, also were tested as UV protectants. Both compounds were ineffective when tested alone. When EGCG and caffeine were combined, UV protection increased in a synergistic manner, but <35% of the original virus activity was maintained. This study demonstrated that coffee was comparable to green tea and black tea as a UV protectant. Further studies should be conducted to optimize their use in biopesticide formulations.

In vitro anticancer effects of insect tea in TCA8113 cells.

PubMed

Qian, Yu; Li, Gui-Jie; Wang, Rui; Zhou, Ya-Lin; Sun, Peng; Zhao, Xin

2014-01-01

Insect tea is widely used a traditional drink or traditional Chinese medicine in China. This study was conducted with an aim to determine the in vitro anticancer effect of Insect tea in cancer cells. The anticancer effects of Insect tea were evaluated in human tongue carcinoma TCA8113 cells using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry analysis, nuclear staining with 4,6-diamidino-2-phenylindole (DAPI), reverse transcription-polymerase chain reaction (RT-PCR) analysis, and western bolt assay. At 200 μg/mL, Insect tea inhibited the growth of TCA8113 cells by 80.7%, which was higher than the inhibition caused by 100 μg/mL Insect tea but lower than that of 200 μg/mL green tea. Compared to the control cancer cells, Insect tea significantly (P<0.05) induced apoptosis as determined by DAPI staining and flow cytometry analysis results. Insect tea significantly induced apoptosis in cancer cells by upregulating BAX, CASP3, CASP9 and downregulating BCL2. Genes encoding nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) were significantly downregulated by Insect tea, demonstrating its anti-inflammatory properties. Insect tea also exerted a great anti-metastasis effect on cancer cells as demonstrated by decreased expression of matrix metalloproteinase (MMP) genes and increased expression of tissue inhibitors of metalloproteinases (TIMPs). The results showed that Insect tea has good in vitro anticancer effects in TCA8113 cells, like green tea.

Direct scavenging of nitric oxide and superoxide by green tea.

PubMed

Nakagawa, T; Yokozawa, T

2002-12-01

In the present study, we investigated the free radical scavenging effects of green tea extract and green tea tannin mixture and its components using a nitric oxide (NO) and superoxide (O(2)(-)) generating system in vitro. Green tea extract showed direct scavenging activity against NO and O(2)(-) and green tea tannin mixture, at the same concentration, showed high scavenging activity. Comparison of the activities of seven pure compounds isolated from green tea tannin mixture showed that (-)-epigallocatechin 3-O-gallate (EGCg), (-)-gallocatechin 3-O-gallate (GCg) and (-)-epicatechin 3-O-gallate (ECg) had higher scavenging activities than (-)-epigallocatechin (EGC), (+)-gallocatechin (GC), (-)-epicatechin (EC) and (+)-catechin (C), showing the importance of the structure of flavan-3-ol linked to gallic acid for this activity. Among the gallate-free tannins, EGC and GC were more effective O(2)(-) scavengers than EC and C, indicating the O-trihydroxy structure in the B ring is an important determinant of such activity. However, this structure did not affect the NO scavenging activity. These findings confirm that green tea tannin has excellent antioxidant properties, which may be involved in the beneficial effect of this compound.

[Polycyclic aromatic hydrocarbons (PAHs) in herbs and fruit teas].

PubMed

Ciemniak, Artur

2005-01-01

Polycyclic aromatic hydrocarbons (PAHs) of which benzo[a]pyrene is the most commonly studied and measured, are fused - ring aromatic compounds formed in both natural and man made processes and are found widely distributed throughout the human environment. PAHs occur as contaminants in different food categories and beverages including water, vegetables, fruit, cereals, oils and fats, barbecued and smoked meat. The sources of PAHs in food are predominantly from environmental pollution and food processing. PAHs emissions from automobile traffic and industry activities were show to influence the PAHs levels in vegetables and fruits. The present study was carried out to determine levels of 16 basic PAHs in herbs and fruit teas. The method was based on the hexane extraction and cleaned up by florisil cartridge. The extracts were analysed by GC-MS. The levels of total PAHs varied from 48,27 microg/kg (hibiscus tea) to 1703 microg/kg (green tea). The highest level of BaP was found in lime tea (74,2 microg/kg).

Green tea extract (epigallocatechin-3-gallate) reduces efficacy of radiotherapy on prostate cancer cells.

PubMed

Thomas, Francis; Holly, Jeff M P; Persad, Rajendra; Bahl, Amit; Perks, Claire M

2011-08-01

To assess the influence of epigallocatechin-3-gallate (EGCG) on the efficacy of ionizing radiation on prostate cancer cells because of the increased use of dietary interventions, especially by patients with prostate cancer. Radiotherapy is used to treat localized prostate cancer. Some people consume green tea (EGCG) as a chemopreventive agent against prostate cancer. Green tea can act as an antioxidant and induce superoxide dismutase enzymes, which could scavenge the free oxygen radicals generated by radiotherapy. Prostate cancer cell line DU145 cells were treated with EGCG or radiotherapy, or both. Cell death was assessed using trypan blue cell counting, and apoptosis was confirmed by assessing poly (adenosine phosphate ribose) polymerase cleavage. The antioxidant potential was assessed using Western immunoblotting for manganese superoxide dismutase and copper zinc superoxide dismutase enzymes. Radiotherapy was delivered using a linear accelerator. Cell cycle analysis was performed using flow cytometry. Radiotherapy at 3.5 Gy induced a 5.9-fold increase in apoptosis of DU145 cells. Subapoptotic doses of EGCG (1.5-7.5 μM) significantly reduced ionizing radiation-induced apoptosis (P < .001), with the inhibitory effect of EGCG on ionizing radiation being most effective when added 30 minutes before radiotherapy (P < .001). In addition, when radiotherapy and EGCG were used together, an approximate 1.5-fold increase in manganese superoxide dismutase levels was seen compared with the control and a 2-fold increase compared with radiotherapy alone. Radiotherapy is effective in inducing apoptosis in DU145 cells, but its effect was significantly reduced in the presence of EGCG, and this was associated with an increase in the induction of manganese superoxide dismutase. Copyright © 2011 Elsevier Inc. All rights reserved.

Ischemia-induced endothelial cell swelling and mitochondrial dysfunction are attenuated by cinnamtannin D1, green tea extract, and resveratrol in vitro.

PubMed

Panickar, Kiran S; Qin, Bolin; Anderson, Richard A

2015-10-01

Polyphenols possess antioxidant and anti-inflammatory properties. Oxidative stress (OS) and inflammation have been implicated in the pathogenesis of cytotoxic brain edema in cerebral ischemia. In addition, OS and pro-inflammatory cytokines also damage the endothelial cells and the neurovascular unit. Endothelial cell swelling may contribute to a leaky blood-brain barrier which may result in vasogenic edema in the continued presence of the existing cytotoxic edema. We investigated the protective effects of polyphenols on cytotoxic cell swelling in bEND3 endothelial cultures subjected to 5 hours oxygen-glucose deprivation (OGD). A polyphenol trimer from cinnamon (cinnamtannin D1), a polyphenol-rich extract from green tea, and resveratrol prevented the OGD-induced rise in mitochondrial free radicals, cell swelling, and the dissipation of the inner mitochondrial membrane potential. Monocyte chemoattractant protein (also called CCL2), a chemokine, but not tumor necrosis factor-α or interleukin-6, augmented the cell swelling. This effect of monochemoattractant protein 1-1 was attenuated by the polyphenols. Cyclosporin A, a blocker of the mitochondrial permeability transition pore, did not attenuate cell swelling but BAPTA-AM, an intracellular calcium chelator did, indicating a role of [Ca(2+)]i but not the mPT in cell swelling. These results indicate that the polyphenols reduce mitochondrial reactive oxygen species and subsequent cell swelling in endothelial cells following ischemic injury and thus may reduce brain edema and associated neural damage in ischemia. One possible mechanism by which the polyphenols may attenuate endothelial cell swelling is through the reduction in [Ca(2+)]i.

Green Tea Polyphenols Stimulate Mitochondrial Biogenesis and Improve Renal Function after Chronic Cyclosporin A Treatment in Rats

PubMed Central

Rehman, Hasibur; Krishnasamy, Yasodha; Haque, Khujista; Lemasters, John J.; Schnellmann, Rick G.; Zhong, Zhi

2013-01-01

Our previous studies showed that an extract from Camellia sinenesis (green tea), which contains several polyphenols, attenuates nephrotoxicity caused by cyclosporine A (CsA). Since polyphenols are stimulators of mitochondrial biogenesis (MB), this study investigated whether stimulation of MB plays a role in green tea polyphenol protection against CsA renal toxicity. Rats were fed a powdered diet containing green tea polyphenolic extract (0.1%) starting 3 days prior to CsA treatment (25 mg/kg, i.g. daily for 3 weeks). CsA alone decreased renal nuclear DNA-encoded oxidative phosphorylation (OXPHOS) protein ATP synthase-β (AS-β) by 42%, mitochondrial DNA (mtDNA)-encoded OXPHOS protein NADH dehydrogenase-3 (ND3) by 87% and their associated mRNAs. Mitochondrial DNA copy number was also decreased by 78% by CsA. Immunohistochemical analysis showed decreased cytochrome c oxidase subunit IV (COX-IV), an OXPHOS protein, in tubular cells. Peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α, the master regulator of MB, and mitochondrial transcription factor-A (Tfam), the transcription factor that regulates mtDNA replication and transcription, were 42% and 90% lower, respectively, in the kidneys of CsA-treated than in untreated rats. These results indicate suppression of MB by chronic CsA treatment. Green tea polyphenols alone and following CsA increased AS-β, ND3, COX-IV, mtDNA copy number, PGC-1α mRNA and protein, decreased acetylated PGC-1α, and increased Tfam mRNA and protein. In association with suppressed MB, CsA increased serum creatinine, caused loss of brush border and dilatation of proximal tubules, tubular atrophy, vacuolization, apoptosis, calcification, and increased neutrophil gelatinase-associated lipocalin expression, leukocyte infiltration, and renal fibrosis. Green tea polyphenols markedly attenuated CsA-induced renal injury and improved renal function. Together, these results demonstrate that green tea polyphenols attenuate CsA-induced

A randomized controlled trial of green tea catechins in protection against ultraviolet radiation–induced cutaneous inflammation12

PubMed Central

Farrar, Mark D; Nicolaou, Anna; Clarke, Kayleigh A; Mason, Sarah; Massey, Karen A; Dew, Tristan P; Watson, Rachel EB; Williamson, Gary; Rhodes, Lesley E

2015-01-01

Background: Safe systemic protection from the health hazards of ultraviolet radiation (UVR) in sunlight is desirable. Green tea is consumed globally and is reported to have anti-inflammatory properties, which may be mediated through the impact on cyclooxygenase and lipoxygenase pathways. Recent data suggest that green tea catechins (GTCs) reduce acute UVR effects, but human trials examining their photoprotective potential are scarce. Objective: We performed a double-blind, randomized, placebo-controlled trial to examine whether GTCs protect against clinical, histologic, and biochemical indicators of UVR-induced inflammation. Design: Healthy adults (aged 18–65 y, phototypes I–II) were randomly allocated to 1350 mg encapsulated green tea extract (540 mg GTC) with 50 mg vitamin C or placebo twice daily for 3 mo. Impact on skin erythema, dermal leukocytic infiltration, and concentrations of proinflammatory eicosanoids was assessed after solar-simulated UVR challenge, and subject compliance was determined through assay of urinary GTC metabolite epigallocatechin glucuronide. Results: Volunteers were assigned to the active (n = 25) or the placebo (n = 25) group. After supplementation, median (IQR) sunburn threshold (minimal erythema dose) was 28 (20–28) and 20 (20–28) mJ/cm2 in the active and placebo groups, respectively (nonsignificant), with no difference in AUC analysis for measured erythema index after a geometric series of 10 UVR doses. Skin immunohistochemistry showed increased neutrophil and CD3+ T-lymphocyte numbers post-UVR in both groups (P < 0.01) with no statistically significant differences between groups after supplementation. Cyclooxygenase and lipoxygenase metabolites prostaglandin E2 (vasodilator) and 12-hydroxyeicosatetraenoicacid (chemoattractant), respectively, increased after UVR (P < 0.05), with no differences between supplementation groups. Conclusion: Oral GTC (1080 mg/d) with vitamin C over 3 mo did not significantly reduce skin erythema

Volatile N-nitrosamine inhibition after intake Korean green tea and Maesil (Prunus mume SIEB. et ZACC.) extracts with an amine-rich diet in subjects ingesting nitrate.

PubMed

Choi, S Y; Chung, M J; Sung, N J

2002-07-01

The formation of carcinogenic nitrosamines under simulated gastric conditions was studied during the incubation of amine rich food and nitrate, and its possible inhibition by adding kumquat, sweet orange, strawberry, garlic, kale juices, Maesil (Prunus mume) and green tea extracts. The strawberry, kale juices, Maesil and green tea extracts were equally effective in reducing the formation of N-nitrosodimethylamine (NDMA). The fruits of P. mume SIEB. et ZACC. (Korean name, Maesil) have been used as a traditional drug and health food in Korea. During four weeks of test (designated EW1, EW2, EW3 and EW4; experiment week 1, 2, 3 and 4 diets) volunteers consumed a diet of low nitrate and amine (EW1) and consumed a fish meal rich in amines as nitrosatable precursors in combination with intake of nitrate-containing drinking water without (EW2) or with Maesil and green tea extracts (EW3 and EW4, respectively). The intake of nitrate-containing drinking water (340 mg nitrate/100 ml) resulted in a significant rise in mean salivary nitrate and nitrite concentrations and in mean urinary nitrate levels. Mean urinary nitrate was increased to 455.0+/-66.2, 334.6+/-67.8 and 333.4+/-50.7 mg/18 h after the nitrate intake of EW2, EW3 and EW4, respectively. Significant increases in urinary dimethylamine and trimethylamine levels were observed in consumption of diets (EW2, EW3, and EW4) rich in amine and nitrate. Maesil and green tea extract in EW3 and EW4 enhanced the increase of urinary dimethylamine and trimethylamine levels. Urinary excretion of N-nitrosodimethylamine in consumption of diet rich in nitrate and amine (EW2) increased to 6504.4+/-2638.7 ng/18 h from 257.0+/-112.0 ng/18 h of low nitrate and amine diet (EW1). Korean green tea and Maesil extracts in nitrate and amine rich diet reduced the excretion of N-nitrosodimethylamine to 249.7+/-90.6 and 752.7+/-595.3 ng/18 h, respectively, compared with 6504.4+/-2638.7 ng /18 h after ingestion of TD1 diet.

Electrosprayed Polyvinylpyrrolidone (PVP) Submicron Particles Loaded by Green Tea Extracts

NASA Astrophysics Data System (ADS)

Kamaruddin; Sriyanti, I.; Edikresnha, D.; Munir, M. M.; Khairurrijal, K.

2018-05-01

Electrospraying technique has been successfully used to synthesize composite submicron particles of polyvinylpyrrolidone (PVP) and green tea extract (GTE). The precursor solutions were PVP in ethanol (15 wt%) and GTE in ethanol (10 wt%), which were then mixed at varying ratio. The mixed solution then underwent electrospraying process at an applied voltage of 15 kV, a distance of collector to the nozzle at 15 cm, and a flow rate of 3 µL/min. The composite submicron particles of PVP-GTE showed smooth and fine spherical morphology without fibers or beaded fibers. To a certain degree, the increase of GTE content in the PVP-GTE mixed solution decreased the average diameter of PVP-GTE composite particles. Moreover, the analysis of the FTIR spectra confirmed the existing molecular interaction between PVP and GTE in the composite submicron particles as shown by the shift of PVP wavenumber towards GTE, which has typically smaller wavenumber.

Therapeutic properties of green tea against environmental insults

PubMed Central

Chen, Lixia; Mo, Huanbiao; Zhao, Ling; Gao, Weimin; Wang, Shu; Cromie, Meghan M; Lu, Chuanwen; Wang, Jia-Sheng; Shen, Chwan-Li

2016-01-01

Pesticides, smoke, mycotoxins, polychlorinated biphenyls, 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. Green tea, the non-oxidized and non-fermented form of tea that contains several polyphenols, including green tea catechins, exhibits protective effects against these environmental toxins and toxicants in preclinical studies and to a much-limited extent, in clinical trials. The protective effects are collectively mediated by antioxidant, anti-inflammatory, anti-mutagenic, hepato- and neuroprotective, and anti-carcinogenic activities. In addition, green tea modulates signaling pathway including NFκB and ERK pathways, preserves mitochondrial membrane potential, inhibits caspase-3 activity, down-regulates pro-apoptotic proteins, and induces the phase II detoxifying pathway. The bioavailability and metabolism of green tea and its protective effects against environmental insults induced by pesticides, smoke, mycotoxins, polychlorinated biphenyls, and arsenic are reviewed in this paper. Future studies with emphasis on clinical trials should identify biomarkers of green tea intake, examine the mechanisms of action of green tea polyphenols, and investigate potential interactions of green tea with other toxicant-modulating dietary factors. PMID:27723473

Green tea diet decreases PCB 126-induced oxidative stress in mice by upregulating antioxidant enzymes

PubMed Central

Newsome, Bradley J; Petriello, Michael C; Han, Sung Gu; Murphy, Margaret O; Eske, Katryn E; Sunkara, Manjula; Morris, Andrew J; Hennig, Bernhard

2013-01-01

Superfund chemicals such as polychlorinated biphenyls pose a serious human health risk due to their environmental persistence and link to multiple diseases. Selective bioactive food components such as flavonoids have been shown to ameliorate PCB toxicity, but primarily in an in vitro setting. Here, we show that mice fed a green tea-enriched diet and subsequently exposed to environmentally relevant doses of coplanar PCB exhibit decreased overall oxidative stress primarily due to the upregulation of a battery of antioxidant enzymes. C57BL/6 mice were fed a low fat diet supplemented with green tea extract (GTE) for 12 weeks and exposed to 5 μmol PCB 126/kg mouse weight (1.63 mg/kg-day) on weeks 10, 11 and 12 (total body burden: 4.9 mg/kg). F2-Isoprostane and its metabolites, established markers of in vivo oxidative stress, measured in plasma via HPLC-MS/MS exhibited five-fold decreased levels in mice supplemented with GTE and subsequently exposed to PCB compared to animals on a control diet exposed to PCB. Livers were collected and harvested for both mRNA and protein analyses, and it was determined that many genes transcriptionally controlled by AhR and Nrf2 proteins were upregulated in PCB-exposed mice fed the green tea supplemented diet. An increased induction of genes such as SOD1, GSR, NQO1 and GST, key antioxidant enzymes, in these mice (green tea plus PCB) may explain the observed decrease in overall oxidative stress. A diet supplemented with green tea allows for an efficient antioxidant response in the presence of PCB 126 which supports the emerging paradigm that healthful nutrition may be able to bolster and buffer a physiological system against the toxicities of environmental pollutants. PMID:24378064

Green tea and the skin.

PubMed

Hsu, Stephen

2005-06-01

Plant extracts have been widely used as topical applications for wound-healing, anti-aging, and disease treatments. Examples of these include ginkgo biloba, echinacea, ginseng, grape seed, green tea, lemon, lavender, rosemary, thuja, sarsaparilla, soy, prickly pear, sagebrush, jojoba, aloe vera, allantoin, feverwort, bloodroot, apache plume, and papaya. These plants share a common character: they all produce flavonoid compounds with phenolic structures. These phytochemicals are highly reactive with other compounds, such as reactive oxygen species and biologic macromolecules, to neutralize free radicals or initiate biological effects. A short list of phenolic phytochemicals with promising properties to benefit human health includes a group of polyphenol compounds, called catechins, found in green tea. This article summarizes the findings of studies using green tea polyphenols as chemopreventive, natural healing, and anti-aging agents for human skin, and discusses possible mechanisms of action.

Combination of Antioxidants from Different Sources Could Offer Synergistic Benefits: A Case Study of Tea and Ginger Blend.

PubMed

Makanjuola, Solomon A; Enujiugha, Victor N; Omoba, Olufunmilayo S; Sanni, David M

2015-11-01

Tea and ginger are plants with high antioxidant potential. Combinations of antioxidants from different sources could also produce synergistic antioxidant effects. This study investigated the influence of solvent on antioxidant content of tea, ginger, and tea + ginger blends. Under the investigated extraction conditions, water was the most effective extraction solvent to maximise peroxide scavenging and iron chelating activity of tea, ginger, and their blends. Aqueous ethanol was the most effective solvent to maximise ABTS radical scavenging activity and ethanol was the best solvent to maximise DPPH radical scavenging activity. A good multivariate regression model that explains the relationship between the total flavonoid content of the extracts and their antioxidant activities was obtained (R2 and Q2 of 0.93 and 0.83, respectively). Extracts of tea-ginger blends exhibited synergistic effects in their ABTS and DPPH radical scavenging activity.

Exposure of a Dengue Vector to Tea and Its Waste: Survival, Developmental Consequences, and Significance for Pest Management.

PubMed

Dieng, Hamady; Tan Yusop, Nur Syafiqah Bt; Kamal, Nurafidah Natasyah Bt; Ahmad, Abu Hassan; Ghani, Idris Abd; Abang, Fatimah; Satho, Tomomitsu; Ahmad, Hamdan; Zuharah, Wan Fatma; Majid, Abdul Hafiz Ab; Morales, Ronald E; Morales, Noppawan P; Hipolito, Cirilo N; Noweg, Gabriel Tonga

2016-05-11

Dengue mosquitoes are evolving into a broader global public health menace, with relentless outbreaks and the rise in number of Zika virus disease cases as reminders of the continued hazard associated with Aedes vectors. The use of chemical insecticides-the principal strategy against mosquito vectors-has been greatly impeded due to the development of insecticide resistance and the shrinking spectrum of effective agents. Therefore, there is a pressing need for new chemistries for vector control. Tea contains hundreds of chemicals, and its waste, which has become a growing global environmental problem, is almost as rich in toxicants as green leaves. This paper presents the toxic and sublethal effects of different crude extracts of tea on Aedes albopictus. The survival rates of larvae exposed to tea extracts, especially fresh tea extract (FTE), were markedly lower than those in the control treatment group. In addition to this immediate toxicity against different developmental stages, the extracts tested caused a broad range of sublethal effects. The developmental time was clearly longer in containers with tea, especially in those with young larvae (YL) and FTE. Among the survivors, pupation success was reduced in containers with tea, which also produced low adult emergence rates with increasing tea concentration. The production of eggs tended to be reduced in females derived from the tea treatment groups. These indirect effects of tea extracts on Ae. albopictus exhibited different patterns according to the exposed larval stage. Taken together, these findings indicate that tea and its waste affect most key components of Ae. albopictus vectorial capacity and may be useful for dengue control. Reusing tea waste in vector control could also be a practical solution to the problems associated with its pollution.

Molecular and cellular targets affected by green tea extracts in vascular cells

USDA-ARS?s Scientific Manuscript database

Consumption of green or black tea has been associated with a lower risk for the development of cardiovascular diseases, but despite many studies, a firm connection has not been delineated. Several molecular and cellular mechanisms may play a role in the preventive activity of tea. As reviewed here, ...

Effect of supercritical carbon dioxide decaffeination on volatile components of green teas.

PubMed

Lee, S; Park, M K; Kim, K H; Kim, Y-S

2007-09-01

Volatile components in regular and decaffeinated green teas were isolated by simultaneous steam distillation and solvent extraction (SDE), and then analyzed by GC-MS. A total of 41 compounds, including 8 alcohols, 15 terpene-type compounds, 10 carbonyls, 4 N-containing compounds, and 4 miscellaneous compounds, were found in regular and decaffeinated green teas. Among them, linalool and phenylacetaldehyde were quantitatively dominant in both regular and decaffeinated green teas. By a decaffeination process using supercritical carbon dioxide, most volatile components decreased. The more caffeine was removed, the more volatile components were reduced in green teas. In particular, relatively nonpolar components such as terpene-type compounds gradually decreased according to the decaffeination process. Aroma-active compounds in regular and decaffeinated green teas were also determined and compared by aroma extract dilution analysis (AEDA). Most greenish and floral flavor compounds such as hexanal, (E)-2-hexenal, and some unknown compounds disappeared or decreased after the decaffeination process.

Effect of Green Tea Phytochemicals on Mood and Cognition.

PubMed

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.

How Does Alkali Aid Protein Extraction in Green Tea Leaf Residue: A Basis for Integrated Biorefinery of Leaves.

PubMed

Zhang, Chen; Sanders, Johan P M; Xiao, Ting T; Bruins, Marieke E

2015-01-01

Leaf protein can be obtained cost-efficiently by alkaline extraction, but overuse of chemicals and low quality of (denatured) protein limits its application. The research objective was to investigate how alkali aids protein extraction of green tea leaf residue, and use these results for further improvements in alkaline protein biorefinery. Protein extraction yield was studied for correlation to morphology of leaf tissue structure, protein solubility and hydrolysis degree, and yields of non-protein components obtained at various conditions. Alkaline protein extraction was not facilitated by increased solubility or hydrolysis of protein, but positively correlated to leaf tissue disruption. HG pectin, RGII pectin, and organic acids were extracted before protein extraction, which was followed by the extraction of cellulose and hemi-cellulose. RGI pectin and lignin were both linear to protein yield. The yields of these two components were 80% and 25% respectively when 95% protein was extracted, which indicated that RGI pectin is more likely to be the key limitation to leaf protein extraction. An integrated biorefinery was designed based on these results.

Herbal tea extract combined with light-induced significant in vitro cytotoxicity of human bladder cancer cells

NASA Astrophysics Data System (ADS)

Nseyo, Unyime; Kim, Albert; Stavropoulos, Nicholas E.; Skalkos, Dimitris; Nseyo, U. U.; Chung, Theodore D.

2005-04-01

The anti-inflammatory, anti-microbial, antiviral, and antidepressant activities of the Greek herb, Hypericum Perforatum L, HP L, have been attributed to the total extract or single constituents. We investigated the use of the extract,specifically of the polar methanolic fraction (PMF) of Epirus"HPL in photodynamic therapy (PDT) alone and in combination with recombinant Interferon-a2b (IFN) and gemcitabine (GCB) in the treatment of human bladder cancer cells. The PMF was extracted from the dry herb with methanol, followed by liquid-liquid extraction with petroleum ether. T-24 bladder cancer cells were plated (105 cells/well) and placed in the incubator (370 C, 5%CO) for 24 hours prior to addition of drugs. PMF 60ug/ml was added and incubation continued. After 24 hours, the cells were subjected to laser light (630nm) treatment with 0, 1, 4 and 8 Joules. After reincubation for 24 hours, IFN, (50,000 IU) or GCB, (2ug/ml) was added to the PDT-treated cells. After this incubation cell survival was assessed by the MTT assay. PMF-PDT alone-induced percent cell kill of 0%, 8%, 44% and 80% versus 31%, 64 and 86 % for PMF-PDT and IFN, versus 63%, 80% and 88% for MPF-PDT plus GCB at 1, 2, 4 and 8 Joules respectively. IFN and GCB induced 20% and 53% cell kill respectively. Our data suggest that MPF may be an effective agent for in vitro photodynamic therapy. PMF-PDT combined with Intron A, or gemcitabine achieved improved kill of cultured bladder cancer cells. Confirmation of these results in preclinical studies may lead to clinical trials.

Synthesis of molecularly imprinted polymers using acrylamide-β-cyclodextrin as a cofunctional monomer for the specific capture of tea saponins from the defatted cake extract of Camellia oleifera.

PubMed

Guo, Huiqin; Xiong, Jingjing; Ma, Wentian; Wu, Minghuo; Yan, Liushui; Li, Kexin; Liu, Yu

2016-11-01

Molecularly imprinted polymers were synthesized using mixed tea saponins as a template and acrylamide-β-cyclodextrin as a cofunctional monomer for the specific binding and purification of tea saponins from the defatted cake extract of Camellia oleifera. The adsorption properties of the prepared polymers were systematically evaluated including adsorption kinetics, adsorption isotherms, and selective recognition characteristics. It showed that the adsorption kinetics followed the pseudo first-order kinetic model (R 2 = 0.995) with an equilibrium time of 3 h, adsorption isotherm data fitted well with the Langmuir-Freundlich model (R 2 = 0.984) with an adsorption capacity of 14.23 mg/g. The relative selectivity coefficient (k´) in the presence of the analogues glycyrrhizic acid and glycyrrhetinic acid were 1.16 and 17.21, respectively. The performance of the molecularly imprinted polymers as solid-phase extraction materials was investigated and the results indicated that using acrylamide-β-cyclodextrin as a cofunctional monomer improved both the adsorption capacity and active sites stability of the imprinted polymers. The solid-phase extraction using the polymers as packing materials was subsequently applied for the separation of tea saponins in raw C. oleifera press extract, and targets were obtained with a purity reaching 89%. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Densitometric HPTLC analysis of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams.

PubMed

Alam, Prawez

2013-08-01

To develop and validate a simple, accurate HPTLC method for the analysis of 8-gingerol and to determine the quantity of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams. The analysis was performed on 10×20 cm aluminium-backed plates coated with 0.2 mm layers of silica gel 60 F254 (E-Merck, Germany) with n-hexane: ethyl acetate 60: 40 (v/v) as mobile phase. Camag TLC Scanner III was used for the UV densitometric scanning at 569. This system was found to give a compact spot of 8-gingerol at retention factor (Rf) value of (0.39±0.04) and linearity was found in the ranges 50-500 ng/spot (r (2)=0.9987). Limit of detection (12.76 ng/spot), limit of quantification (26.32 ng/spot), accuracy (less than 2 %) and recovery (ranging from 98.22-99.20) were found satisfactory. The HPTLC method developed for quantification of 8-gingerol was found to be simple, accurate, reproducible, sensitive and is applicable to the analysis of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams.

Influence of agronomic variables on the composition of mate tea leaves (Ilex paraguariensis) extracts obtained from CO2 extraction at 30 degrees C and 175 bar.

PubMed

Esmelindro, Angela Aquino; Girardi, Jonathan Dos Santos; Mossi, Altemir; Jacques, Rosângela Assis; Dariva, Cláudio

2004-04-07

The aim of this work is to assess the influence of light intensity (plants with direct sun exposure and in a controlled light intensity) and age of leaves (6-24 months) on the characteristics of the extracts of mate tea leaves obtained from carbon dioxide at high pressures. Samples of mate were collected in an experiment conducted under agronomic control at Industria e Comercio de Erva-Mate Barão LTDA, Brazil. The content of selected organic compounds of the extracts was evaluated by gas chromatography together with mass spectrometry. Quantitative analysis of caffeine, theobromine, phytol, vitamin E, squalene, and stigmasterol was performed, and the results showed that field variables exert a strong influence on the liquid yield and on the chemical distribution of the extracts.

Analytical separation of tea catechins and food-related polyphenols by high-speed counter-current chromatography.

PubMed

Yanagida, Akio; Shoji, Atsushi; Shibusawa, Yoichi; Shindo, Heisaburo; Tagashira, Motoyuki; Ikeda, Mitsuo; Ito, Yoichiro

2006-04-21

High-speed counter-current chromatography (HSCCC) using the type-J coil planet centrifuge was applied to compositional analysis of tea catechins and separation of other food-related polyphenols. The HSCCC separation of nine different standard compounds and those from extracts of commercial tea leaves was performed with a two-phase solvent system composed of tert-butyl methyl ether-acetonitrile-0.1% aqueous trifluoroacetic acid (TFA) (2:2:3, v/v/v) by eluting the upper organic phase at a flow rate of 2 ml/min. The main compounds in the extract of non-fermented green tea were found to be monomeric catechins, their galloylated esters and caffeine. In addition to these compounds, oxidized pigments, such as hydrophobic theaflavins (TFs) and polar thearubigins (TRs) were also separated and detected from the extracts of semi-fermented oolong tea and fermented black tea. Furthermore, several food-related polyphenols, such as condensed catechin oligomers (procyanidins), phenolic acids and flavonol glycosides were clearly separated under the same HSCCC condition. These separation profiles of HSCCC provide useful information about the hydrophobic diversity of these bioactive polyphenols present in various types of teas and food products.

Black tea aroma inhibited increase of salivary chromogranin-A after arithmetic tasks.

PubMed

Yoto, Ai; Fukui, Natsuki; Kaneda, Chisa; Torita, Shoko; Goto, Keiichi; Nanjo, Fumio; Yokogoshi, Hidehiko

2018-01-24

Growing attention has been paid to the effects of food flavor components on alleviating negative brain functions caused by stressful lifestyles. In this study, we investigated the alleviating effect of two kinds of black tea aromas on physical and psychological stress induced by the Uchida-Kraepelin test, based on salivary chromogranin-A (CgA) levels as a stress marker and subjective evaluations (Profile of Mood States). Compared with the water exposure control, inhaling black tea aroma (Darjeeling and Assam in this study) induced lower salivary CgA concentration levels after 30 min of mental stress load tasks. This anti-stress effect of black tea aroma did not differ between the two tea types even though the concentration of the anti-stress components in the Darjeeling tea aroma was higher than that in the Assam aroma. However, Darjeeling tea aroma tended to decrease the tension and/or anxiety score immediately after the first exposure. Inhaling black tea aroma may diminish stress levels caused by arithmetic mental stress tasks, and Darjeeling tea aroma tended to improve mood before mental stress load.

Purification of a water extract of Chinese sweet tea plant (Rubus suavissimus S. Lee) by alcohol precipitation

PubMed Central

Koh, Gar Yee; Chou, Guixin; Liu, Zhijun

2009-01-01

The aqueous extraction process of the leaves of Rubus suavissimus often brings in a large amount of non-active polysaccharides as part of the constituents. To purify this water extract for potential elevated bioactivity, alcohol precipitation (AP) consisting of gradient regimens was applied, and its resultants were examined through colorimetric and HPLC analyses. AP was effective in partitioning the aqueous crude extract into a soluble supernatant and an insoluble precipitant, and its effect varied significantly with alcohol regimens. Generally, the higher the alcohol concentration, the purer was the resultant extract. At its maximum, approximately 36% (w/w) of the crude extract, of which 23% was polysaccharides, was precipitated and removed, resulting in a purified extract consisting of over 20% bioactive marker compounds (gallic acid, ellagic acid, rutin, rubusoside, and steviol monoside). The removal of 11% polysaccharides from the crude water extract by using alcohol precipitation was complete at 70% alcohol regimen. Higher alcohol levels resulted in even purer extracts, possibly by removing some compounds of uncertain bioactivity. Alcohol precipitation is an effective way of removing polysaccharides from the water extract of sweet tea plant and could be used as an initial simple purification tool for many water plant extracts that contain large amounts of polysaccharides. PMID:19419169

Green tea diet decreases PCB 126-induced oxidative stress in mice by up-regulating antioxidant enzymes.

PubMed

Newsome, Bradley J; Petriello, Michael C; Han, Sung Gu; Murphy, Margaret O; Eske, Katryn E; Sunkara, Manjula; Morris, Andrew J; Hennig, Bernhard

2014-02-01

Superfund chemicals such as polychlorinated biphenyls pose a serious human health risk due to their environmental persistence and link to multiple diseases. Selective bioactive food components such as flavonoids have been shown to ameliorate PCB toxicity, but primarily in an in vitro setting. Here, we show that mice fed a green tea-enriched diet and subsequently exposed to environmentally relevant doses of coplanar PCB exhibit decreased overall oxidative stress primarily due to the up-regulation of a battery of antioxidant enzymes. C57BL/6 mice were fed a low-fat diet supplemented with green tea extract (GTE) for 12 weeks and exposed to 5 μmol PCB 126/kg mouse weight (1.63 mg/kg-day) on weeks 10, 11 and 12 (total body burden: 4.9 mg/kg). F2-isoprostane and its metabolites, established markers of in vivo oxidative stress, measured in plasma via HPLC-MS/MS exhibited fivefold decreased levels in mice supplemented with GTE and subsequently exposed to PCB compared to animals on a control diet exposed to PCB. Livers were collected and harvested for both messenger RNA and protein analyses, and it was determined that many genes transcriptionally controlled by aryl hydrocarbon receptor and nuclear factor (erythroid-derived 2)-like 2 proteins were up-regulated in PCB-exposed mice fed the green tea-supplemented diet. An increased induction of genes such as SOD1, GSR, NQO1 and GST, key antioxidant enzymes, in these mice (green tea plus PCB) may explain the observed decrease in overall oxidative stress. A diet supplemented with green tea allows for an efficient antioxidant response in the presence of PCB 126, which supports the emerging paradigm that healthful nutrition may be able to bolster and buffer a physiological system against the toxicities of environmental pollutants. Copyright © 2014 Elsevier Inc. All rights reserved.

Green tea extracts reduce leukocyte cell-Derived chemotaxin 2 and selenoprotein P levels in the livers of C57BL/6J mice fed a high-fat diet.

PubMed

Onishi, Shintaro; Kitazawa, Hidefumi; Meguro, Shinichi; Tokimitsu, Ichiro

2018-05-31

Epidemiological studies suggest that green tea extracts (GTEs), including catechins such as epigallocatechin gallate and epicatechin gallate, have a beneficial effect on obesity, hyperglycemia, insulin resistance, endothelial dysfunction, and inflammation. Although several studies have shown that catechins directly modulate the cellular and molecular alterations in the liver tissue, the contributions of indirect mechanisms underlying these systemic effects of catechins remain unclear. In this study, we report that, in the C57BL/6J mouse liver, GTEs reduce high-fat diet-induced increases in the levels of hepatokines, liver-derived secretary proteins such as leukocyte cell-derived chemotaxin 2 and selenoprotein P production, which have been shown to induce systemic adverse effects, including several metabolic diseases. These findings suggest that the systemic effects of GTEs involve the regulation of hepatokine production as an indirect mechanism.

[Isolation and purification of seven catechin compounds from fresh tea leaves by semi-preparative liquid chromatography].

PubMed

Gong, Zhihong; Chen, Si; Gao, Jiangtao; Li, Meihong; Wang, Xiaxia; Lin, Jun; Yu, Xiaomin

2017-11-08

An effective and simple method was established to simultaneously purify seven tea catechins (gallocatechin (GC), epigallocatechin (EGC), catechin (C), epigallocatechin-3- O -gallate (EGCG), epicatechin (EC), epigallocatechin-3- O -(3- O -methyl)-gallate (EGCG3"Me) and epicatechin-3- O -gallate (ECG)) from fresh tea leaves by semi-preparative high performance liquid chromatography (HPLC). Fresh leaves of Tieguanyin tea were successively extracted with methanol and chloroform. Then crude catechins were precipitated from the aqueous fraction of chloroform extraction by adding lead subacetate. Crude catechins were used for the isolation of the seven target catechin compounds by semi-preparative HPLC. Methanol-water and acetonitrile-water were sequentially used as mobile phases. After two rounds of semi-preparative HPLC, all target compounds were achieved with high purities (>90%). The proposed method was tested on two additional tea cultivars and showed similar results. This method demonstrated a simple and efficient strategy based on solvent extraction, ion precipitation and semi-preparative HPLC for the preparation of multiple catechins from tea leaves.

Effects of aqueous extracts of dried calyx of sour tea (Hibiscus sabdariffa L.) on polygenic dyslipidemia: A randomized clinical trial.

PubMed

Hajifaraji, Majid; Matlabi, Mohammad; Ahmadzadeh-Sani, Farihe; Mehrabi, Yadollah; Rezaee, Mohammad Salem; Hajimehdipour, Homa; Hasanzadeh, Abbas; Roghani, Katayoun

2018-01-01

Dyslipidemia has been considered as a major risk factor for coronary heart disease. Alternative medicine has a significant role in treatment of dyslipidemia. There are controversial findings regarding the effects of sour tea on dyslipidemia. The aim of this study was to evaluate the impact of aqueous extract of dried calyx of sour tea on polygenic dyslipidemia. This clinical trial was done on 43 adults (30-60 years old) with polygenic dyslipidemia that were randomly assigned to the intervention and control groups. The control group was trained in lifestyle modifications at baseline. The intervention group was trained for lifestyle modifications at baseline and received two cups of sour tea daily, and both groups were followed up for 12 weeks. Lipid profile was evaluated at baseline, and six and 12 weeks following the intervention. In addition, dietary and physical activity assessed at baseline for twelve weeks. Mean concentration of total cholesterol, HDL-C and LDL-C significantly decreased by up to 9.46%, 8.33%, and 9.80%, respectively, after 12 weeks in the intervention group in comparison to their baseline values. However, LDL-C/HDL-C ratio significantly increased by up to 3.15%, following 12 weeks in the control group in comparison to their baseline values. This study showed no difference in lipid profiles between the two groups, except for HDL-C concentrations. sour tea may have significant positive effects on lipid profile of polygenic dyslipidemia subjects and these effect might be attributed to its anthocyanins and inflation factor content. Therefore, sour tea intake with recommended dietary patterns and physical activity can be useful in regulation of lipid profile in patients with polygenic dyslipidemia.

[Identification of green tea brand based on hyperspectra imaging technology].

PubMed

Zhang, Hai-Liang; Liu, Xiao-Li; Zhu, Feng-Le; He, Yong

2014-05-01

Hyperspectral imaging technology was developed to identify different brand famous green tea based on PCA information and image information fusion. First 512 spectral images of six brands of famous green tea in the 380 approximately 1 023 nm wavelength range were collected and principal component analysis (PCA) was performed with the goal of selecting two characteristic bands (545 and 611 nm) that could potentially be used for classification system. Then, 12 gray level co-occurrence matrix (GLCM) features (i. e., mean, covariance, homogeneity, energy, contrast, correlation, entropy, inverse gap, contrast, difference from the second-order and autocorrelation) based on the statistical moment were extracted from each characteristic band image. Finally, integration of the 12 texture features and three PCA spectral characteristics for each green tea sample were extracted as the input of LS-SVM. Experimental results showed that discriminating rate was 100% in the prediction set. The receiver operating characteristic curve (ROC) assessment methods were used to evaluate the LS-SVM classification algorithm. Overall results sufficiently demonstrate that hyperspectral imaging technology can be used to perform classification of green tea.

Dietary Intervention of Artemisia and Green Tea Extracts to Rejuvenate Helicobacter pylori-Associated Chronic Atrophic Gastritis and to Prevent Tumorigenesis.

PubMed

Jeong, Migyeong; Park, Jong-Min; Han, Young-Min; Kangwan, Napapan; Kwon, Sang-Oh; Kim, Bok-Nam; Kim, Won-Hee; Hahm, Ki-Baik

2016-02-01

As nonmicrobial dietary approach is capable of controlling Helicobacter pylori infection, we evaluated the efficacy of long-term dietary administration of Artemisia and/or green tea extracts on H. pylori-initiated, high-salt-promoted chronic atrophic gastritis and gastric tumorigenesis mouse model. Helicobacter pylori-infected and high-salt-diet-administered C57BL/6 mice were administered with Artemisia extracts (MP group) and/or green tea extracts (GT group) for 36 weeks in addition to the control group (ES group, gastroprotective drug, ecabet sodium 30 mg/kg, diet pellet). Gross and pathological gastric lesions were evaluated after 24 and 36 weeks, respectively, and their underlying molecular changes were measured in gastric homogenates. Detailed mechanisms were further evaluated in in vitro cell models. The erythematous and nodular changes and mucosal ulcerative and erosive lesions were noted in the control group at 24 weeks. MP, GT, MPGT, and ES groups all showed significantly ameliorated pathologic lesion compared to the control group (p < .05). After the 36 weeks, scattered nodular masses with some central ulcers and thin gastric surface were noted in the control stomach, whereas no tumorous lesion and milder atrophic changes were observed in all MP, GT, and MPGT groups except ES group (p < .05). On molecular analysis, increased expressions of COX-2, TNF-α, IL-6, lipid peroxide, and activated STAT3 relevant to H. pylori infection were significantly decreased with MPGT administration (p < .01), whereas HSP70 was significantly increased. PGDH expressions, core tumor suppressor involved in carcinogenesis, were significantly decreased with H. pylori infection (p < .05), but significantly increased in MPGT group (p < .05). Increased mucosal apoptotic index noted in the control group was significantly decreased with MP and/or GT along with significantly preserved gastric gastroprotective mediators (p < .01) such as mucins, HSP27, and HSP70. H. pylori-induced serum

The impact of the catechol-O-methyltransferase genotype on vascular function and blood pressure after acute green tea ingestion.

PubMed

Miller, Rosalind J; Jackson, Kim G; Dadd, Tony; Mayes, Andrew E; Brown, A Louise; Lovegrove, Julie A; Minihane, Anne M

2012-06-01

Evidence for the benefits of green tea catechins on vascular function is inconsistent, with genotype potentially contributing to the heterogeneity in response. Here, the impact of the catechol-O-methyltransferase (COMT) genotype on vascular function and blood pressure (BP) after green tea extract ingestion are reported. Fifty subjects (n = 25 of the proposed low-activity [AA] and of the high-activity [GG] COMT rs4680 genotype), completed a randomized, double-blind, crossover study. Peripheral arterial tonometry, digital volume pulse (DVP), and BP were assessed at baseline and 90 min after 1.06 g of green tea extract or placebo. A 5.5 h and subsequent 18.5 h urine collection was performed to assess green tea catechin excretion. A genotype × treatment interaction was observed for DVP reflection index (p = 0.014), with green tea extract in the AA COMT group attenuating the increase observed with placebo. A tendency for a greater increase in diastolic BP was evident at 90 min after the green tea extract compared to placebo (p = 0.07). A genotypic effect was observed for urinary methylated epigallocatechin during the first 5.5 h, with the GG COMT group demonstrating a greater concentration (p = 0.049). Differences in small vessel tone according to COMT genotype were evident after acute green tea extract. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

[Functional saponins in tea flower (flower buds of Camellia sinensis): gastroprotective and hypoglycemic effects of floratheasaponins and qualitative and quantitative analysis using HPLC].

PubMed

Yoshikawa, Masayuki; Wang, Tao; Sugimoto, Sachiko; Nakamura, Seikou; Nagatomo, Akifumi; Matsuda, Hisashi; Harima, Shoichi

2008-01-01

As a part of our characterization studies on the bioactive saponin constituents of tea flowers (Camellia sinensis, flower buds), the methanolic extract and 1-butanol-soluble portion (the saponin fraction) from the flower buds were found to exhibit potent inhibitory effects on ethanol- and indomethacin-induced gastric mucosal lesions in rats and on serum glucose elevation in sucrose-loaded rats. Among the constituents of the 1-butanol-soluble portion, floratheasaponins A, B, and C showed gastroprotective and hypoglycemic activities. Furthermore, we have developed qualitative and quantitative methods using HPLC for the principle saponins, floratheasaponins A-F, in tea flowers, which were previously found to show antiallergic and antiobesity effects. Using those methods, the saponin composition of Indian tea flowers were found to be similar to those of Chinese (Anhui) but not of Japanese tea flowers. On the other hand, it was found that the floratheasaponin contents in tea flowers varied markedly during the blooming period, and they were abundant at half-bloom. Additionally, the contents of caffeine in the tea flowers were examined using HPLC.

Sensory characteristics and consumer acceptability of decaffeinated green teas.

PubMed

Lee, S M; Lee, H-S; Kim, K-H; Kim, K-O

2009-04-01

Green tea has been widely consumed for its mild flavors and its health benefits, yet caffeine in green tea has been a limitation for those who want to avoid it. The limitation brought increase in need for decaffeinated products in the green tea market. Most of the conventional decaffeination techniques applied in food use organic solvents. However, supercritical carbon dioxide fluid extraction (SC-CO2) method is gaining its intension as one of the future decaffeination methods that overcomes the problems of conventional methods. The purpose of this study was to identify sensory characteristics of decaffeinated green teas applied with SC-CO2 method and to observe the relationship with consumer acceptability to elucidate the potentiality of applying SC-CO2 technique in decaffeinated green tea market. Descriptive analysis was performed on 8 samples: green teas containing 4 caffeine levels (10%, 35%, 60%, and 100%) infused at 2 infusing periods (1 or 2 min). It was found that the SC-CO2 process not only reduced caffeine but also decreased some important features of original tea flavors. Two groups were recruited for consumer acceptability test: one (GP I, N = 52), consuming all types of green teas including hot/cold canned teas; and the other (GP II, N = 40), only consuming the loose type. While GP II liked original green tea the most, GP I liked highly decaffeinated green teas. Although the SC-CO2 method had limitations of losing complex flavors of green teas, it appeared to have future potential in the decaffeinated green tea market within or without the addition of desirable flavors.

Effect of decaffeination of coffee or tea on gastro-oesophageal reflux.

PubMed

Wendl, B; Pfeiffer, A; Pehl, C; Schmidt, T; Kaess, H

1994-06-01

Coffee and tea are believed to cause gastro-oesophageal reflux; however, the effects of these beverages and of their major component, caffeine, have not been quantified. The aim of this study was to evaluate gastro-oesophageal reflux induced by coffee and tea before and after a decaffeination process, and to compare it with water and water-containing caffeine. Three-hour ambulatory pH-metry was performed on 16 healthy volunteers, who received 300 ml of (i) regular coffee, decaffeinated coffee or tap water (n = 16), (ii) normal tea, decaffeinated tea, tap water, or coffee adapted to normal tea in caffeine concentration (n = 6), and (iii) caffeine-free and caffeine-containing water (n = 8) together with a standardized breakfast. Regular coffee induced a significant (P < 0.05) gastro-oesophageal reflux compared with tap water and normal tea, which were not different from each other. Decaffeination of coffee significantly (P < 0.05) diminished gastro-oesophageal reflux, whereas decaffeination of tea or addition of caffeine to water had no effect. Coffee adapted to normal tea in caffeine concentration significantly (P < 0.05) increased gastro-oesophageal reflux. Coffee, in contrast to tea, increases gastro-oesophageal reflux, an effect that is less pronounced after decaffeination. Caffeine does not seem to be responsible for gastro-oesophageal reflux which must be attributed to other components of coffee.

Evaluation and application of prebiotic and probiotic ingredients for development of ready to drink tea beverage.

PubMed

Tewari, Shweta; Dubey, Kriti Kumari; Singhal, Rekha S

2018-04-01

Ready-to-drink (RTD) ice tea is a ready prepared tea, produced from green and black tea originating from same plant Camellia sinensis . The objective of this study was to determine the effect of prebiotics [galacto-oligosaccharide (GOS), fructo-oligosaccharide (FOS), and inulin] or synbiotic ingredients (GOS, FOS, inulin, and Lactobacillus acidophilus ) on the sensory properties and consumer acceptability of RTD. The quality of green tea extract (GTE) and black tea extract (BTE) was improved with pretreatment of cellulase and pectinase enzymes. The combined enzymatic extraction amplified total extractives up to 76% in GTE and 72% in BTE. Total polyphenol was found to be enhanced to 24% in GTE and 19% in BTE. GTE was further selected for development of RTD in two different formats; synbiotic RTD and prebiotic RTD premix and analyzed for sensory attributes (colour, aroma, taste, and acceptability). Synbiotic RTD was also evaluated for stability over a period of 28 days at 4 °C. Synbiotic RTD developed an unpleasant flavor and aroma during the shelf life. Premix format of RTD developed using spray drying was reconstituted and found to be functionally and sensorially acceptable.

Protein Oxidation and Sensory Quality of Brine-Injected Pork Loins Added Ascorbate or Extracts of Green Tea or Maté during Chill-Storage in High-Oxygen Modified Atmosphere.

PubMed

Jongberg, Sisse; Tørngren, Mari Ann; Skibsted, Leif H

2018-01-15

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain ~12%, NaCl ~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 °C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O₂ and 20% CO₂) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops.

Protein Oxidation and Sensory Quality of Brine-Injected Pork Loins Added Ascorbate or Extracts of Green Tea or Maté during Chill-Storage in High-Oxygen Modified Atmosphere

PubMed Central

Tørngren, Mari Ann

2018-01-01

Background: Ascorbate is often applied to enhance stability and robustness of brine-injected pork chops sold for retail, but may affect protein oxidation, while plant extracts are potential substitutes. Methods: Brine-injected pork chops (weight-gain ~12%, NaCl ~0.9%) prepared with ascorbate (225 ppm), green tea extract (25 ppm gallic acid equivalents (GAE)), or maté extract (25 ppm GAE) stored (5 °C, seven days) in high-oxygen atmosphere packaging (MAP: 80% O2 and 20% CO2) were analyzed for color changes, sensory quality, and protein oxidation compared to a control without antioxidant. Results: No significant differences were observed for green tea and maté extracts as compared to ascorbate when evaluated based on lipid oxidation derived off-flavors, except for stale flavor, which maté significantly reduced. All treatments increased the level of the protein oxidation product, α-aminoadipic semialdehyde as compared to the control, and ascorbate was further found to increase thiol loss and protein cross-linking, with a concomitant decrease in the sensory perceived tenderness. Conclusions: Green tea and maté were found to equally protect against lipid oxidation derived off-flavors, and maté showed less prooxidative activity towards proteins as compared to ascorbate, resulting in more tender meat. Maté is a valuable substitute for ascorbate in brine-injected pork chops. PMID:29342928

Phytochemical Screening and Antimicrobial Properties of a Common Brand of Black Tea (Camellia sinensis) Marketed in Nigerian Environment.

PubMed

Olosunde, O Funmilayo; Abu-Saeed, Kamaldeen; Abu-Saeed, Muhammad Buhari

2012-01-01

This study is aimed at determining chemical constituents and antimicrobial activities of a common brand of black tea (Lipton®) in Nigeria. Standard methods were employed for testing carbohydrates, tannins, saponins, flavonoids, alkaloids, steroids and terpenes in the tea. Antimicrobial activities of methanolic and aqueous extracts of the tea on four standard strains of organisms: Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus subtilis were also determined by standard methods. RESULTs showed that the tea contains tannin and reducing sugar. Concentrations of 1%, 2%, 4%, 6%, 8% and 10% aqueous and methanolic extract of black tea were prepared and their zones of inhibition determined against the four test organisms using the cup plate method. This was compared with zones for standard disc Gentamicin (10 µg) and Erythromycin (15 µg). Pseudomonas aeruginosa was sensitive to 2% to 10% aqueous extracts and intermediate to 6%, 8% and 10% methanolic extracts. E. coli was intermediately sensitive to 6%, 8% and 10% aqueous extract and 2% to 10% methanolic extracts. B. subtilis was intermediately sensitive to 4%, 6% and 8% aqueous extract and 4% to 10% methanolic extract but sensitive to 10% aqueous extract. Staph.aureus was intermediately sensitive to 4% to 10% aqueous extracts and 2% to 10% methanolic extracts. B. subtilis had the lowest MIC values of both aqueous and methanolic extracts. In conclusion, this study has shown that Lipton® has antimicrobial properties on E.coli, Staph.aureus, B.subtilis and Ps.aeruginosa and contains tannin and reducing sugar.

[Short-term screening of anticarcinogenic ingredients of tea by cell biology assays].

PubMed

Liu, L; Han, C; Chen, J

1998-01-01

By using a panel of short term cell biology assays, several ingredients of tea (tea pigments, caffeine, tea polysaccharide, tea polyphenols tablet and mixed tea) were screened in order to investigate their anticarcinogenic effects. The cytokinesis block micronuclei test in V79 cells induced by mitomycin, the test of metabolic cooperation between V79 and M cells and the test of growth ability of Hela cells in soft agar were used in the screening. The results showed that the six kinds of tea ingredients tested were effective in the test involved in different stages of carcinogenesis, i.e. initiation, promotion and progression. The effects of mixed tea and tea pigments were the strongest among the ingredients tested.

Antioxidant activity of an invasive plant, Melastoma malabathricum and its potential as herbal tea product

NASA Astrophysics Data System (ADS)

Sari, N. M.; Kuspradini, H.; Amirta, R.; Kusuma, I. W.

2018-04-01

East Kalimantan possesses abundant biodiversity of tropical medicinal plant. Melastoma malabathricum (known locally as karamunting, senduduk) is an invasive plant along with other species in the family of Melastomataceae with traditional medicinal purposes. This research explored the potential of Karamunting (M. malabathricum) plant for its antioxidant activity and the potential as a material for herbal tea product. The plant was macerated to yield ethanolic extract, and at the same time plant powder was packed into tea bags and extracted with hot water to obtain the infused water. Antioxidant activity was evaluated by DPPH radical scavenging assay. The results showed that the ethanol extracts of plant samples displayed ability to inhibit DPPH free radical formation by 82% at 50 ppm concentration. Evaluation of the tea water extract showed that the highest inhibition obtained by leaves powder by 90% and fruit 88% at 1 minutes immersion time. This finding suggest that leaves and fruit of M. malabathricum plants display potential as herbal tea material having antioxidant activity if the safety aspect can be assured.

Tea waste: an effective and economic substrate for oyster mushroom cultivation.

PubMed

Yang, Doudou; Liang, Jin; Wang, Yunsheng; Sun, Feng; Tao, Hong; Xu, Qiang; Zhang, Liang; Zhang, Zhengzhu; Ho, Chi-Tang; Wan, Xiaochun

2016-01-30

Tea waste is the residue that remains after tea leaves have been extracted by hot water to obtain water-soluble components. The waste contains a re-usable energy substrate and nutrients which may pollute the environment if they are not dealt with appropriately. Other agricultural wastes have been widely studied as substrates for cultivating mushrooms. In the present study, we cultivated oyster mushroom using tea waste as substrate. To study the feasibility of re-using it, tea waste was added to the substrate at different ratios in different experimental groups. Three mushroom strains (39, 71 and YOU) were compared and evaluated. Mycelia growth rate, yield, biological efficiency and growth duration were measured. Substrates with different tea waste ratios showed different growth and yield performance. The substrate containing 40-60% of tea waste resulted in the highest yield. Tea waste could be used as an effective and economic substrate for oyster mushroom cultivation. This study also provided a useful way of dealing with massive amounts of tea waste. © 2015 Society of Chemical Industry.

Anti-stress effects of drinking green tea with lowered caffeine and enriched theanine, epigallocatechin and arginine on psychosocial stress induced adrenal hypertrophy in mice.

PubMed

Unno, Keiko; Hara, Ayane; Nakagawa, Aimi; Iguchi, Kazuaki; Ohshio, Megumi; Morita, Akio; Nakamura, Yoriyuki

2016-11-15

Theanine, an amino acid in tea, has significant anti-stress effects on animals and humans. However, the anti-stress effects of drinking green tea have not yet been elucidated. The present study aimed to explore anti-stress effects of green tea and roles of tea components in a mouse model of psychosocial stress. We examined anti-stress effects of three types of green teas, theanine-rich "Gyokuro", standard "Sencha", and Sencha with lowered caffeine (low-caffeine green tea). Furthermore, the roles of tea components such as caffeine, catechins, and other amino acids in anti-stress effects were examined. To prepare low-caffeine green tea, plucked new tea leaves were treated with a hot-water spray. Mice were psychosocially stressed from a conflict among male mice under confrontational housing. Mice consumed each tea that was eluted with room temperature water ad libitum. As a marker for the stress response, adrenal hypertrophy was compared with mice that ingested water. Caffeine was significantly lowered by spraying hot-water on tea leaves. While epigallocatechin gallate (EGCG) is the main catechin in tea leaves, epigallocatechin (EGC) was mainly infused into water at room temperature. Adrenal hypertrophy was significantly suppressed in mice that ingested theanine-rich and low-caffeine green tea that were eluted with water at room temperature. Caffeine and EGCG suppressed the anti-stress effects of theanine while EGC and arginine (Arg) retained these effects. These results suggest that drinking green tea exhibits anti-stress effects, where theanine, EGC and Arg cooperatively abolish the counter-effect of caffeine and EGCG on psychosocial stress induced adrenal hypertrophy in mice. Copyright © 2016 Elsevier GmbH. All rights reserved.

Risks associated with consumption of herbal teas.

PubMed

Manteiga, R; Park, D L; Ali, S S

1997-01-01

Plants have been used for medicinal purposes for centuries. Health-oriented individuals are turning to herbal teas as alternatives to caffeinated beverages such as coffee, tea, and cocoa and for low-caloric supplements. The popularity of herbal tea consumption has increased significantly during the past two decades in the U.S. Hundreds of different teas made up of varied mixtures of roots, leaves, seeds, barks, or other parts of shrubs, vines, or trees are sold in health food stores. Although chemists have been characterizing toxic plant constituents for over 100 years, toxicological studies of herbal teas have been limited and, therefore, the safety of many of these products is unknown. Plants synthesize secondary metabolites that are not essential in the production of energy and whose role may be in the defense mechanisms as plant toxins to their interactions with other plants, herbivores, and parasites. Pyrrolizidine alkaloids (PAs) were among the first naturally occurring carcinogens identified in plant products, and their presence in herbal teas is a matter of public health significance. Some herbal tea mixtures and single-ingredient herbal teas have been analyzed for toxic/mutagenic potential by bioassay and chromatographic techniques. Numerous human and animal intoxications have been associated with naturally occurring components, including pyrrolizidine alkaloids, tannins, and safrole. Thus, the prevention of human exposure to carcinogens or mutagens present in herbal tea mixture extracts is crucial. Preparation of infusion drinks prepared from plants appears to concentrate biologically active compounds and is a major source of PA poisoning. The quantity and consumption over a long period of time is of major concern. It is recommended that widespread consumption of herbal infusions should be minimized until data on the levels and varieties of carcinogens, mutagens, and toxicants are made available.

Densitometric HPTLC analysis of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams

PubMed Central

Alam, Prawez

2013-01-01

Objective To develop and validate a simple, accurate HPTLC method for the analysis of 8-gingerol and to determine the quantity of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams. Methods The analysis was performed on 10×20 cm aluminium-backed plates coated with 0.2 mm layers of silica gel 60 F254 (E-Merck, Germany) with n-hexane: ethyl acetate 60: 40 (v/v) as mobile phase. Camag TLC Scanner III was used for the UV densitometric scanning at 569. Results This system was found to give a compact spot of 8-gingerol at retention factor (Rf) value of (0.39±0.04) and linearity was found in the ranges 50-500 ng/spot (r2=0.9987). Limit of detection (12.76 ng/spot), limit of quantification (26.32 ng/spot), accuracy (less than 2 %) and recovery (ranging from 98.22-99.20) were found satisfactory. Conclusions The HPTLC method developed for quantification of 8-gingerol was found to be simple, accurate, reproducible, sensitive and is applicable to the analysis of 8-gingerol in Zingiber officinale extract and ginger-containing dietary supplements, teas and commercial creams. PMID:23905021

Safety and anti-hyperglycemic efficacy of various tea types in mice

PubMed Central

Han, Manman; Zhao, Guangshan; Wang, Yijun; Wang, Dongxu; Sun, Feng; Ning, Jingming; Wan, Xiachun; Zhang, Jinsong

2016-01-01

Tea, a beverage consumed worldwide, has proven anti-hyperglycemic effects in animal models. Better efficacies of tea beverages are frequently associated with high-dose levels, whose safety attracts considerable attention. Based on the inherent nature of tea catechin oxidation, fresh tea leaves are manufactured into diverse tea types by modulating the oxidation degree of catechins. The present study aimed to assess various tea types for their safety properties and anti-hyperglycemic effects. Mice were allowed free access to tea infusion (1:30, w/v) for one week, and the rare smoked tea caused salient adverse reactions, including hepatic and gastrointestinal toxicities; meanwhile, the widely-consumed green and black teas, unlike the rare yellow tea, suppressed growth in fast-growing healthy mice. When mice were fed a high-fat diet and allowed free access to tea infusion (1:30, w/v) for 25 days, only yellow tea significantly reduced blood glucose. Therefore, various teas showed different safety profiles as well as anti-hyperglycemic efficacy strengths. To achieve an effective and safe anti-hyperglycemic outcome, yellow tea, which effectively suppressed high-fat diet-induced early elevation of hepatic thioredoxin-interacting protein, is an optimal choice. PMID:27531374

α-Farnesene and ocimene induce metabolite changes by volatile signaling in neighboring tea (Camellia sinensis) plants.

PubMed

Zeng, Lanting; Liao, Yinyin; Li, Jianlong; Zhou, Ying; Tang, Jinchi; Dong, Fang; Yang, Ziyin

2017-11-01

Herbivore-induced plant volatiles (HIPVs) act as direct defenses against herbivores and as indirect defenses by attracting herbivore enemies. However, the involvement of HIPVs in within-plant or plant-to-plant signaling is not fully clarified. Furthermore, in contrast to model plants, HIPV signaling roles in crops have hardly been reported. Here, we investigated HIPVs emitted from tea (Camellia sinensis) plants, an important crop used for beverages, and their involvement in tea plant-to-plant signaling. To ensure uniform and sufficient exposure to HIPVs, jasmonic acid combined with mechanical damage (JAMD) was used to simulate herbivore attacks. Metabonomics techniques based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry and gas chromatography-mass spectrometry were employed to determine metabolite changes in undamaged tea plants exposed to JAMD-stimulated volatiles. JAMD-stimulated volatiles mainly enhanced the amounts of 1-O-galloyl-6-O-luteoyl-α-d-glucose, assamicain C, 2,3,4,5-tetrahydroxy-6-oxohexyl gallate, quercetagitrin, 2-(2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-4-oxo-4H-chromen-8-yl)-4,5-dihydroxy-6-(hydroxymethyl)-tetrahydro-2H-pyran-3-yl, 3,4-dimethoxybenzoate, 1,3,4,5,6,7-hexahydroxyheptan-2-one, and methyl gallate in neighboring undamaged tea leaves. Furthermore, α-farnesene and β-ocimene, which were produced after JAMD treatments, were identified as two main JAMD-stimulated volatiles altering metabolite profiles of the neighboring undamaged tea leaves. This research advances our understanding of the ecological functions of HIPVs and can be used to develop crop biological control agents against pest insects in the future. Copyright © 2017 Elsevier B.V. All rights reserved.

Induction of neutral endopeptidase (NEP) activity of SK-N-SH cells by natural compounds from green tea.

PubMed

Ayoub, Shereen; Melzig, Matthias F

2006-04-01

Deposition of amyloid beta-peptide as senile plaques in the brain is one of the neuropathological hallmarks of Alzheimer's disease, which is the most prevalent progressive neurodegenerative disease leading to dementia. Neutral endopeptidase is one of the major beta-amyloid-degrading enzymes in the brain. To examine the influence of different polyphenols and other natural products from green tea extract (from Camellia sinensis, Theaceae), we used the neuroblastoma cell line SK-N-SH and studied the changes in the specific cellular neutral endopeptidase activity after long-term treatment with these substances. We have shown that caffeine leads to an increase in specific cellular neutral endopeptidase activity more than theophylline, theobromine or theanine. We have also shown that the combination of epicatechin, epigallocatechin and epigallocatechingallate with caffeine, theobromine or theophylline induced cellular neutral endopeptidase activity. It is suggested that the enhancement of cellular neutral endopeptidase activity by green tea extract and its natural products might be correlated with an elevated level of intracellular cyclic adenosine monophosphate.

Cardiovascular and Metabolic Responses to the Ingestion of Caffeinated Herbal Tea: Drink It Hot or Cold?

PubMed

Maufrais, Claire; Sarafian, Delphine; Dulloo, Abdul; Montani, Jean-Pierre

2018-01-01

Aim: Tea is usually consumed at two temperatures (as hot tea or as iced tea). However, the importance of drink temperature on the cardiovascular system and on metabolism has not been thoroughly investigated. The purpose of this study was to compare the cardiovascular, metabolic and cutaneous responses to the ingestion of caffeinated herbal tea (Yerba Mate) at cold or hot temperature in healthy young subjects. We hypothesized that ingestion of cold tea induces a higher increase in energy expenditure than hot tea without eliciting any negative effects on the cardiovascular system. Methods: Cardiovascular, metabolic and cutaneous responses were analyzed in 23 healthy subjects (12 men and 11 women) sitting comfortably during a 30-min baseline and 90 min following the ingestion of 500 mL of an unsweetened Yerba Mate tea ingested over 5 min either at cold (~3°C) or hot (~55°C) temperature, according to a randomized cross-over design. Results: Averaged over the 90 min post-drink ingestion and compared to hot tea, cold tea induced (1) a decrease in heart rate (cold tea: -5 ± 1 beats.min -1 ; hot tea: -1 ± 1 beats.min -1 , p < 0.05), double product, skin blood flow and hand temperature and (2) an increase in baroreflex sensitivity, fat oxidation and energy expenditure (cold tea: +8.3%; hot tea: +3.7%, p < 0.05). Averaged over the 90 min post-drink ingestion, we observed no differences of tea temperature on cardiac output work and mean blood pressure responses. Conclusion: Ingestion of an unsweetened caffeinated herbal tea at cold temperature induced a greater stimulation of thermogenesis and fat oxidation than hot tea while decreasing cardiac load as suggested by the decrease in the double product. Further experiments are needed to evaluate the clinical impact of unsweetened caffeinated herbal tea at a cold temperature for weight control.

Behavioral and electroantennographic responses of the tea mosquito, Helopeltis theivora, to female sex pheromones.

PubMed

Sachin, James P; Selvasundaram, R; Babu, A; Muraleedharan, N

2008-12-01

Responses of the tea mosquito, Helopeltis theivora (Waterhouse) (Hemiptera: Miridae), a major pest of tea, to female sex pheromone compounds were measured using wind tunnel and electroantennogram (EAG) bioassays. In the wind tunnel, male tea mosquitoes were found to be most attracted to a dichloromethane extract of the female thorax. Gas chromatography-mass spectrometry (GC-MS) analysis of female thoracic extracts and dynamic head space samples of virgin females showed the presence of five compounds: (Z)-3 hexenyl acetate, (Z)-3 hexenyl butanoate, (E)-2 hexenyl pentanoate, 2,4 dimethyl pentanal, and (E)-2-hexenol. Male tea mosquitoes were attracted to blends of (Z)-3 hexenyl acetate and (E)-2-hexenol in the wind tunnel with a 1:5 ratio eliciting the greatest response. EAG recordings of male antenna confirmed the ability of this blend to evoke antennal responses in male insects. Similarly active EAG responses were recorded toward female thoracic extract and a blend of (Z)-3 hexenyl acetate and (E)-2-hexenol. Behavioral responses of adult males are mediated by a blend of volatile female sex pheromone compounds, (Z)-3 hexenyl acetate and (E)-2-hexenol, at a ratio of 1:5. This female sex pheromone blend may be useful for tea mosquito control and management programs.

Whitening Effect of Black Tea Water Extract on Brown Guinea Pig Skin

PubMed Central

Choi, So-Young

2011-01-01

To evaluate the whitening effect of black tea water extract (BT), BT was topically applied to artificially hyperpigmented spots on the back skins of brown guinea-pigs (weight: 450~500 g) induced by 1,500 mJ/ cm2 of ultraviolet B (UVB) irradiation. The test compounds of 30 μl were applied twice a day, six days a week, for four weeks. The artificially hyperpigmented spots were divided into 5 groups: control (UVB + saline, C), vehicle control [UVB + propylene glycol: ethanol: water (5 : 3 : 2), VC], positive control (UVB + 2% hydroquinone, PC), experimental 1 (UVB + 1% BT), experimental 2 (UVB + 2% BT). After 4-week application, the spots were removed by biopsy punch under anesthetic condition and used as specimens for the histological examination. The total polyphenol and flavonoid contents of BT were 104 and 91 mg/g, respectively. The electron-donating ability of BT revealed a dose-dependent response, showing the excellent capacities of 86% at 800 μg/ml. The artificially hyperpigmented spots treated with the PC and BT were obviously lightened compared to the C and VC groups. At the fourth week, the melanin indices for the PC and BT groups were significantly lower (p < 0.00l) than those of the C and VC groups. In histological examination, PC and BT groups were significantly reduced in the melanin pigmentation, the proliferation of melanocytes and the synthesis of melanosomes compared to the C and VC groups. It is found that BT inhibits the proliferation of melanocytes and synthesis of melanosomes in vivo using brown guinea pigs, thereby showing a definite skin whitening effect. PMID:24278566

A physiological model of tea-induced astringency.

PubMed

Nayak, A; Carpenter, G H

2008-10-20

The mechanism by which solutions containing polyphenols are perceived as astringent is not clearly understood. Salivary proline-rich proteins and histatins are products of salivary glands and rapidly bind polyphenols - thought to be the main astringent compound in such as tea and wine. However it is unclear how this interaction leads to the altered oral mouthfeel known as astringency which is characterised by a dry, puckered feeling all around the mouth. To determine the role of saliva in the perception of astringency a protocol was used to decrease the volume of saliva from the mouth (by washing with water) and then by chewing to increase the volume of saliva above resting levels. Following each of these conditions subjects tasted the same solution of black tea and were asked to rate the relative astringency. Compared to the astringency rating of black tea at rest the majority of subjects (10 out of 15) perceived an increase in astringency following washing the mouth with water. Most subjects then perceived a decrease in astringency following chewing compared to the previous state. In all subjects a reduction in salivary proteins was detected following water washout and an increase above resting levels detected following chewing although there was no change in oral mucosal wetness. A separate experiment revealed several of the proteins interacting following the water washout were salivary in origin. We conclude that salivary proteins in solution inhibit the mouthfeeling of astringency which is mediated, at least in part, by salivary proteins adhered to buccal mucosal cells.

An inverse association between tea consumption and colorectal cancer risk.

PubMed

Chen, Yuetong; Wu, Yuan; Du, Mulong; Chu, Haiyan; Zhu, Lingjun; Tong, Na; Zhang, Zhengdong; Wang, Meilin; Gu, Dongying; Chen, Jinfei

2017-06-06

It is well known that the tea extracts, mainly polyphenols as chemo-preventive elements, could act as cancer progression blockers. Although the association between tea consumption and colorectal cancer risk has been widely investigated, the results still remain inconsistent. We conducted a dose-response meta-analysis to evaluate their relationships by enrolling qualified 29 literatures. The summary odds ratio (OR) of colorectal cancer for the highest vs. lowest tea consumption was 0.93 with 0.87-1.00 of 95% confidence intervals (CIs) among all studies with modest heterogeneity (P = 0.001, I2 = 43.4%). Stratified analysis revealed that tea, especially green tea, had a protective effect among female and rectal cancer patients. Particularly, the dose-response analysis showed that there was a significant inverse association between an increment of 1 cup/day of tea consumption and colorectal cancer risk in the subgroup of the green tea drinking (OR = 0.98, 95% CI = 0.96-1.01, Pnonlinear = 0.003) and female (OR = 0.68, 95% CI = 0.56-0.81, Pnonlinear < 0.001). Our findings indicate that tea consumption has an inverse impact on colorectal cancer risk, which may have significant public health implications in the prevention of colorectal cancer and further similar researches.

Can hibiscus tea lower blood pressure

USDA-ARS?s Scientific Manuscript database

Hibiscus sabdariffa is a common ingredient found in blended herbal teas, and beverages made from the dried calyces of this plant are popular worldwide. In vitro studies have shown that H. sabdariffa has antioxidant properties and, in animal models of hypertension, extracts of this plant lower blood ...

Characterization of tea polyphenols as potential environment-friendly fire retardants

NASA Astrophysics Data System (ADS)

Yao, Fengqi; Zhai, Chunjie; Wang, Haihui; Tao, Junjun

2018-02-01

In this work we investigated the oxidation properties of tea polyphenols and their potential as the fire retardants. Two types of tea polyphenols were adopted, which were extracted from red tea and green tea leaves, respectively. Their macroscopic performance during pyrolysis and oxidation at elevated temperatures were examined by using a heating furnace. Mass change, heat evolution and gas products of tea polyphenols during heating in air were also monitored by using a thermo-gravimetric analyzer (TGA) integrated with a differential scanning calorimeter (DSC) in conjunction with online Fourier Transform Infrared Spectroscopy (FTIR) and mass spectroscopy (MS). A tea polyphenol sample first becomes a brown semi-fluid after heating, and gradually turns into highly-porous black chars with significantly expanded volume. By raising the temperature to ∼550 °C at a rate of 10 °C/min, the mass of a sample reduces by nearly 70% to form a large quantity of inert gases that are mainly composed of H2O and CO2. It was found that the aerial oxidation products of tea polyphenols in the solid phase possess good heat insulation property; meanwhile, the substantial release of a lot of water and its evaporation during oxidation of tea polyphenols removes a large amount of heat from a sample located in a heating environment. The heat insulation of tea polyphenols may withstand up to 550 °C. The present work confirms tea polyphenols as potential superior and environment-friendly fire retardants.

Selective determination of aluminum bound with tannin in tea infusion.

PubMed

Erdemoğlu, Sema B; Güçer, Seref

2005-08-01

In this study, an analytical method for indirect measurement of Al bound with tannin in tea infusion was studied. This method utilizes the ability of the tannins to precipitate with protein. Separation conditions were investigated using model solutions. This method is uncomplicated, inexpensive and suitable for real samples. About 34% of the total Al in brew extracted from commercially available teas was bound to condensed and hydrolyzable tannins.

Comparison of the nutrient and chemical contents of traditional Korean Chungtaejeon and green teas.

PubMed

Park, Yong-Seo; Lee, Mi-Kyung; Heo, Buk-Gu; Ham, Kyung-Sik; Kang, Seong-Gook; Cho, Ja-Yong; Gorinstein, Shela

2010-06-01

This study was conducted in order to compare the nutrient and chemical contents of two Korean teas: traditional Chungtaejeon tea (CTJ) with that of green tea (GT). Main bioactive compounds and the antioxidant activities using four radical scavenging assays (ABTS, CUPRAC, FRAP and DPPH) in methanol and acetone extracts of both teas were determined. It was found that the contents of vitamin C, amino acids and total nitrogen in CTJ were lower than that of GT (p < 0.05). Caffeine, reducing sugar and chlorophyll contents in CTJ were similar to GT. Catechin (C), epicatechin (EC), and epigallocatechin (EGC) contents were lower in CTJ than in green tea (p < 0.05), but gallocatechin (GC), epicatechin gallate (ECG), epigallocatechin gallate (EGCG) and catechin gallate (CG) showed no significant differences between CTJ and GT (p >/= 0.05). The contents of polyphenols, flavonoids, flavanols and tannins in CTJ methanol were 229.30 +/- 11.3 mg GAE/g dry weight (DW), 15.24 +/- 0.8 mg CE/g DW, 109.10 +/- 5.1 mg CE/g DW and 25.68 +/- 1.2 mg CE/g DW, respectively, and significantly higher than in acetone extracts (p < 0.05). Flavonoids (quercetin and kaempferol) were higher in GT than in CTJ and myricetin was higher in CTJ (p < 0.05). Threonine and aspartic acid was lower, and glutamic acid was higher in CTJ compared with GT (p < 0.05). Free amino acid content in CTJ and GT showed no significant difference. Potassium and magnesium in CTJ were lower compared to GT, but no significant difference was found for iron, manganese and calcium. Also, the level of the antioxidant activity by all four used assays was significantly higher in CTJ and in methanol was higher than in acetone extracts (p < 0.05). In conclusion, traditional fermented Korean tea Chungtaejeon contains high quantities of bioactive compounds and possesses high antioxidant activity. The contents of the bioactive compounds and the levels of antioxidant activities are significantly higher in methanol than in acetone

Tea production characteristics of tea growers (plantations and smallholdings) and livelihood dimensions of tea workers in Assam, India.

PubMed

Biggs, Eloise M; Gupta, Niladri; Saikia, Sukanya D; Duncan, John M A

2018-04-01

This article provides summary data regarding tea production in Assam, India. Questionnaires were completed by tea producers and focus group discussions undertaken with tea workers. These data are presented for the four main tea growing regions of the state (Cachar, North Bank, South Bank and Upper Assam). Tables detail tea production characteristics of the tea plantations for both large- (> 10 ha) and small- (< 10 ha) holders. Figures provide supplementary information for research by Biggs et al. [1] regarding fertilizer application, landscape management strategies, healthcare provisioning and educational facilities within plantations, as well as detailing the livelihood dimensions of tea workers. The questions posed to producers are also included. For further context underpinning the research for which these data were collated, see 'The tea landscape of Assam: multi-stakeholder insights into sustainable livelihoods under a changing climate' by Biggs et al. [1].

Studies on toxicity, anti-stress and hepato-protective properties of Kombucha tea.

PubMed

Pauline, T; Dipti, P; Anju, B; Kavimani, S; Sharma, S K; Kain, A K; Sarada, S K; Sairam, M; Ilavazhagan, G; Devendra, K; Selvamurthy, W

2001-09-01

The objective of the study was to evaluate toxicity, anti-stress activity and hepato-protective properties of Kombucha tea. Kombucha tea was fed orally for 15 days using three different doses i.e. normal dose, five and ten times the dose. Rats were then sacrificed and various biochemical, and histological parameters were estimated. Anti-stress activity was evaluated either by 1) by exposing animals to cold and hypoxia and estimating the levels of malondialdehyde and reduced glutathione in plasma/blood or 2) by subjecting the animals to restraint stress and recording faecal output. Hepato-toxicity was induced by challenging the animals to an acute dose of paracetamol (1 gm/kg) orally and determining the plasma levels of SGPT, SGOT and MDA. The effect of oral administration of different doses of K-tea to albino rats was examined and the results indicate that K-tea has no significant toxicity as revealed by various biochemical and histopathological parameters. K-tea has been found to prevent lipid peroxidation and fall in reduced glutathione level when rats were exposed to cold and hypoxia in simulated chamber. Further, K-tea has also been found to decrease the Wrap-restraint faecal pellet output in rats. K-tea has also been found to decrease paracetamol induced hepatotoxicity significantly. The study shows that K-tea has anti-stress and hepato-protective activities.

The antioxidant effect of Green Tea Mega EGCG against electromagnetic radiation-induced oxidative stress in the hippocampus and striatum of rats.

PubMed

Ahmed, Nawal A; Radwan, Nasr M; Aboul Ezz, Heba S; Salama, Noha A

2017-01-01

Electromagnetic radiation (EMR) of cellular phones may affect biological systems by increasing free radicals and changing the antioxidant defense systems of tissues, eventually leading to oxidative stress. Green tea has recently attracted significant attention due to its health benefits in a variety of disorders, ranging from cancer to weight loss. Thus, the aim of the present study was to investigate the effect of EMR (frequency 900 MHz modulated at 217 Hz, power density 0.02 mW/cm 2 , SAR 1.245 W/kg) on different oxidative stress parameters in the hippocampus and striatum of adult rats. This study also extends to evaluate the therapeutic effect of green tea mega EGCG on the previous parameters in animals exposed to EMR after and during EMR exposure. The experimental animals were divided into four groups: EMR-exposed animals, animals treated with green tea mega EGCG after 2 months of EMR exposure, animals treated with green tea mega EGCG during EMR exposure and control animals. EMR exposure resulted in oxidative stress in the hippocampus and striatum as evident from the disturbances in oxidant and antioxidant parameters. Co-administration of green tea mega EGCG at the beginning of EMR exposure for 2 and 3 months had more beneficial effect against EMR-induced oxidative stress than oral administration of green tea mega EGCG after 2 months of exposure. This recommends the use of green tea before any stressor to attenuate the state of oxidative stress and stimulate the antioxidant mechanism of the brain.

Cardiovascular and Metabolic Responses to the Ingestion of Caffeinated Herbal Tea: Drink It Hot or Cold?

PubMed Central

Maufrais, Claire; Sarafian, Delphine; Dulloo, Abdul; Montani, Jean-Pierre

2018-01-01

Aim: Tea is usually consumed at two temperatures (as hot tea or as iced tea). However, the importance of drink temperature on the cardiovascular system and on metabolism has not been thoroughly investigated. The purpose of this study was to compare the cardiovascular, metabolic and cutaneous responses to the ingestion of caffeinated herbal tea (Yerba Mate) at cold or hot temperature in healthy young subjects. We hypothesized that ingestion of cold tea induces a higher increase in energy expenditure than hot tea without eliciting any negative effects on the cardiovascular system. Methods: Cardiovascular, metabolic and cutaneous responses were analyzed in 23 healthy subjects (12 men and 11 women) sitting comfortably during a 30-min baseline and 90 min following the ingestion of 500 mL of an unsweetened Yerba Mate tea ingested over 5 min either at cold (~3°C) or hot (~55°C) temperature, according to a randomized cross-over design. Results: Averaged over the 90 min post-drink ingestion and compared to hot tea, cold tea induced (1) a decrease in heart rate (cold tea: −5 ± 1 beats.min−1; hot tea: −1 ± 1 beats.min−1, p < 0.05), double product, skin blood flow and hand temperature and (2) an increase in baroreflex sensitivity, fat oxidation and energy expenditure (cold tea: +8.3%; hot tea: +3.7%, p < 0.05). Averaged over the 90 min post-drink ingestion, we observed no differences of tea temperature on cardiac output work and mean blood pressure responses. Conclusion: Ingestion of an unsweetened caffeinated herbal tea at cold temperature induced a greater stimulation of thermogenesis and fat oxidation than hot tea while decreasing cardiac load as suggested by the decrease in the double product. Further experiments are needed to evaluate the clinical impact of unsweetened caffeinated herbal tea at a cold temperature for weight control. PMID:29681860

Residues and contaminants in tea and tea infusions: a review.

PubMed

Abd El-Aty, A M; Choi, Jeong-Heui; Rahman, Md Musfiqur; Kim, Sung-Woo; Tosun, Alev; Shim, Jae-Han

2014-01-01

Consumers are very aware of contaminants that could pose potential health hazards. Most people drink tea as an infusion (adding hot water); however, in some countries, including India, China and Egypt, tea is drunk as a decoction (tea and water are boiled together). An infusion usually brings the soluble ingredients into solution, whereas a decoction brings all soluble and non-soluble constituents together. Therefore, a cup of tea may contain various kinds of contaminants. This review focuses on green and black tea because they are most commonly consumed. The target was to examine the transfer rate of contaminants - pesticides, environmental pollutants, mycotoxins, microorganisms, toxic heavy metals, radioactive isotopes (radionuclides) and plant growth regulators - from tea to infusion/brewing, factors contributing to the transfer potential and contaminants degradation, and residues in or on the spent leaves. It is concluded that most contaminants leaching into tea infusion are not detected or are detected at a level lower than the regulatory limits. However, the traditional practice of over-boiling tea leaves should be discouraged as there may be a chance for more transfer of contaminants from the tea to the brew.

Microwave heating of tea residue yields polysaccharides, polyphenols, and plant biopolyester.

PubMed

Tsubaki, Shuntaro; Iida, Hiroyuki; Sakamoto, Masahiro; Azuma, Jun-ichi

2008-12-10

Microwave heating was used to produce aqueous-soluble components from green, oolong, and black tea residues. Heating at 200-230 degrees C for 2 min extracted 40-50% of polysaccharides and 60-70% of the polyphenols. Solubilization of arabinose and galactose by autohydrolysis occurred with heating above 170 degrees C, whereas heating above 200 degrees C was necessary to solubilize xylose. Catechins were soluble in water by heating at low temperature (110 degrees C); however, new polyphenols having strong antioxidant activity were produced above 200 degrees C. The amount of solubilized materials and antioxidant activity increased with increased fermentation of harvested tea leaves (green tea < oolong tea < black tea). Cutin, a plant biopolyester, remained in the residue after heating as did cellulose and lignin/tannin. The predominant cutin monomer that was recovered was 9,10-epoxy-18-hydroxyoctadecanoic acid, followed by dihydroxyhexadecanoic acid and 9,10,18-trihydroxyoctadecanoic acid.

Characterisation of odorants in roasted stem tea using gas chromatography-mass spectrometry and gas chromatography-olfactometry analysis.

PubMed

Sasaki, Tetsuya; Koshi, Erina; Take, Harumi; Michihata, Toshihide; Maruya, Masachika; Enomoto, Toshiki

2017-04-01

Roasted stem tea has a characteristic flavour, which is obtained by roasting tea stems, by-product of green tea production. This research aims to understand the characteristic odorants in roasted stem tea by comparing it to roasted leaf tea. We revealed potent odorants in commercial roasted stem tea using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry with aroma extract dilution analysis (AEDA). The difference between roasted stem and leaf tea derived from the same tea plants were investigated using GC-MS. Pyrazine compounds exhibited a roasted odour and high flavour dilution (FD) factors, as determined via AEDA. Roasted stem tea was richer in these pyrazines than roasted leaf tea. Geraniol and linalool exhibited high FD factors and a floral odour, and roasted stem tea was richer in these compounds than roasted leaf tea. These results may have a positive impact on the development of tea products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Analyzing organic tea certification and traceability system within the Taiwanese tea industry.

PubMed

Wang, Mao-Chang; Yang, Chin-Ying

2015-04-01

We applied game theory to the organic tea certification process and traceability system used by the Taiwanese tea industry to elucidate the strategic choices made by tea farmers and organic tea certification agencies. Thus, this paper clarifies how relevant variables affect the organic certification process and traceability system used within the tea industry. The findings indicate that farmers who generate high revenues experience failures regarding tea deliveries, cash outflow, damage compensation, and quasi-rent. An additional problem included the high costs yielded when tea farmers colluded with or switched organic tea certification agencies. Furthermore, there could be decreasing levels of personal interest in planting non-organic tea and lowering the costs of planting organic tea and the managerial accounting costs of building comprehensive traceability systems; thus, the analysis yielded strong results and a superior equilibrium. This research is unprecedented, using an innovative model and providing a novel analysis structure for use in the tea industry. These results contribute to the field of literature and should serve as a valuable reference for members of the tea industry, government, and academia. © 2014 Society of Chemical Industry.

Fermentation Characteristics, Tannin Contents and In vitro Ruminal Degradation of Green Tea and Black Tea By-products Ensiled at Different Temperatures

PubMed Central

Kondo, Makoto; Hirano, Yoshiaki; Kita, Kazumi; Jayanegara, Anuraga; Yokota, Hiro-omi

2014-01-01

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at 10°C, 20°C, and 30°C. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at 10°C. The GTS stored at 20°C and 30°C showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on NH3-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and NH3-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and NH3-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin’s activity in the rumen. PMID:25050034

Fermentation Characteristics, Tannin Contents and In vitro Ruminal Degradation of Green Tea and Black Tea By-products Ensiled at Different Temperatures.

PubMed

Kondo, Makoto; Hirano, Yoshiaki; Kita, Kazumi; Jayanegara, Anuraga; Yokota, Hiro-Omi

2014-07-01

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at 10°C, 20°C, and 30°C. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at 10°C. The GTS stored at 20°C and 30°C showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on NH3-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and NH3-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and NH3-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin's activity in the rumen.

Green Tea Polyphenols Attenuated Glutamate Excitotoxicity via Antioxidative and Antiapoptotic Pathway in the Primary Cultured Cortical Neurons.

PubMed

Cong, Lin; Cao, Chang; Cheng, Yong; Qin, Xiao-Yan

2016-01-01

Green tea polyphenols are a natural product which has antioxidative and antiapoptotic effects. It has been shown that glutamate excitotoxicity induced oxidative stress is linked to neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. In this study we explored the neuroprotective effect of green teen polyphenols against glutamate excitotoxicity in the primary cultured cortical neurons. We found that green tea polyphenols protected against glutamate induced neurotoxicity in the cortical neurons as measured by MTT and TUNEL assays. Green tea polyphenols were then showed to inhibit the glutamate induced ROS release and SOD activity reduction in the neurons. Furthermore, our results demonstrated that green tea polyphenols restored the dysfunction of mitochondrial pro- or antiapoptotic proteins Bax, Bcl-2, and caspase-3 caused by glutamate. Interestingly, the neuroprotective effect of green tea polyphenols was abrogated when the neurons were incubated with siBcl-2. Taken together, these results demonstrated that green tea polyphenols protected against glutamate excitotoxicity through antioxidative and antiapoptotic pathways.

Effect of green tea extract microencapsulation on hypertriglyceridemia and cardiovascular tissues in high fructose-fed rats

PubMed Central

Jung, Moon Hee; Seong, Pil Nam; Kim, Myung Hwan; Myong, Na-Hye

2013-01-01

The application of polyphenols has attracted great interest in the field of functional foods and nutraceuticals due to their potential health benefits in humans. However, the effectiveness of polyphenols depends on their bioactivity and bioavailability. In the present study, the bioactive component from green tea extract (GTE) was administrated orally (50 mg/kg body weight/day) as free or in a microencapsulated form with maltodextrin in rats fed a high fructose diet. High fructose diet induced features of metabolic syndrome including hypertriglyceridemia, hyperuricemia, increased serum total cholesterol, and retroperitoneal obesity. In addition, myocardial fibrosis was increased. In rats receiving high fructose diet, the lowering of blood triglycerides, total cholesterol, non esterified fatty acid (NEFA) and uric acid, as well as the reduction in final body weight and retroperitoneal fat weight associated with the administration of GTE, led to a reversal of the features of metabolic syndrome (P < 0.05). In particular, the administration of microencapsulated GTE decreased myocardial fibrosis and increased liver catalase activity consistent with a further alleviation of serum NEFA, and hyperuricemia compared to administration of GTE. Taken together, our results suggest that microencapsulation of the bioactive components of GTE might have a protective effect on cardiovasucular system by attenuating the adverse features of myocardial fibrosis, decreasing uric acid levels and increasing hepatic catalase activity effectively by protecting their bioactivities. PMID:24133615

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

PubMed

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.

Spectrophotometric determination of the tannin contents of various Turkish black tea, beer and wine samples.

PubMed

Tinkiliç, N; Uyanik, A

2001-05-01

This study reports tannin contents of various tea (19), beer (6) and wine (6) samples, produced or sold in Turkey under different brand names. Determinations were carried out by employing a previously reported UV-vis spectrophotometric method. The standard addition procedure was also compared to the direct determination procedure and found to be more reliable. The tannin contents of hot water extracts of tea, tea bag and herbal tea samples ranged between 6.20-8.33, 8.03-6.59 and 2.76-6.54 percent (w/w) respectively. Tannin contents of beer and wine samples determined without extraction were found ranging between 66.36-77.26 and 67.18-107.62 micrograms/mL respectively. Iron contents of analysed wine samples were also found ranging between 0.36 and 10.33 ppm by AAS and no relation is found between tannin and iron contents.

Catechin Composition and Antioxidant Activity of Black Teas in Relation to Brewing Time.

PubMed

Koch, Wojciech; Kukula-Koch, Wirginia; Głowniak, Kazimierz

2017-11-01

Black tea infusions are one of the most popular beverages across the world. Their extract composition depends on several factors, brewing time being one of the most important determinants. The aim of the present study was to determine the catechin composition of different black tea infusions using a validated LC electrospray ionization time-of-flight MS method. Additionally, total phenolic content (TPC) and antioxidant activity of infusions were evaluated using Folin-Ciocalteu reagent and stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH). An optimized LC-MS method enabled the precise identification of the studied catechins [epicatechin (EC), EC gallate (ECG), epigallocatechin (EGC), and epigallocatechin-3-gallate (EGCG)] and gallic acid (GA). The major catechin in all investigated teas was EGC (25.6 mg/100 cm3 after 4 min of brewing). EC was present at the lowest concentration in all extracts. TPC and antiradical scavenging activity were in a good agreement with catechins and GA content. In general, the longer the brewing time, the higher the concentration of catechin, TPC, and antioxidant activity values. However, it should be noted that after 2 min brewing, most phenolics had already been extracted, and extract composition did not significantly change at a prolonged extraction time.

Chemopreventive potential of the tannase-mediated biotransformation of green tea.