Alleviating effects and mechanisms of action of large-leaf yellow tea drinking on diabetes and diabetic nephropathy in mice

Our previous study found that large-leaf yellow tea(LYT)had interesting hypoglycemic activity in high-fat diet-induced obese mice and highly safety in healthy mice. To study the anti-diabetic potential of LYT, the present study further investigated the preventive effects and mechanisms of action of LYT administration on diabetes and diabetic nephropathy in high-fat diet plus streptozotocin-induced diabetic mice. Results showed that LYT infusions(1/100 and 1/50, m/V)as drinking fluid for 4 weeks reduced diabetic polydipsia and polyuria, enhanced glucose tolerance and insulin sensitivity, and lowered fasting blood glucose level. The underlying mechanisms involve downregulation of gluconeogenesis(lower protein levels of TXNIP and FBP and enzyme activity of FBP), upregulation of lipid catabolism(higher protein levels of CPT-1α and PPARα), downregulation of lipogenesis(lower protein level of SREBP-1), and modification of the structure and abundance of gut microbiota to modulate metabolic homeostasis. Moreover, LYT administration prevented diabetic nephropathy, possibly due to reduced glucose-caused osmotic diuresis and lowered levels of renal PKC-β2, NLRP3 as well as membrane PKC-α, AQP2 and glycosylated AQP2 proteins. Taken together, LYT exhibits the activities in alleviating diabetic symptoms, ameliorating glucose and lipid dysmetabolism and fatty liver, and preventing diabetic nephropathy in diabetic mice. These activities may be explored for the prevention and treatment of diabetes in humans.

Characteristics of Superfine Green Tea Powder and Its Application in Food Industry

Superfine green tea powder is a new kind of tea product that can be eaten directly.It provided most of the benefits of whole green tea leaves,with all of the bioactive ingredients.This paper highlighted the characteristics and health benefits of superfine green tea powder,and its applications in food industry.

The 30-Day Oral Administration Studies of Liposoluble Tea Polyphenols in Rats

Tea polyphenols is a natural antioxidant with a variety of biological activity.However,the weak liposolubility and low bioavailability limit their application.As a result,structural modification of tea polyphenols comes into being.The prepared liposoluble tea polyphenols was suggested as a good candidate antioxidant for edible-oil and fats products.But,safety studies on liposoluble tea polyphenols are limited.The objective of the present study was conducted to synthesize liposoluble tea polyphenols and evaluate its toxicity in Sprague-Dawley rats on oral administration at dietary levels of 1,2 and 4% for 30 days.There were no adverse effects on general condition,growth,food intake,feed conversion efficiency,haematology parameters,clinical chemistry values and organ weights.High-dose males exhibited a higher haemoglobin concentration and a lower alanine aminotransferase levels,and high-dose females showed a lower albumin and globulin levels.These slight changes were considered of no toxicological significance.Necropsy and histopathology findings revealed no treatment-related changes in any of the organs.Thus,the results allowed us to conclude that the liposoluble tea polyphenols properly utilized in the oral administration could be devoid of any toxic risk.

Genetic Diversity of Tea Plant(Camellia Sinensis(L.) O.Kuntze)in Wuling Mountainous Area Revealed by ISSR Marker

Genetic diversity and relationship of 183 tea germplasms were assessed by inter-simple sequence repeat(ISSR) marker.The study optimized the ISSR-PCR system for tea plants.Results show that genetic similarity among 183 tea ascensions was between 0.52-0.93,indicating a wide gene pool and a broad genetic variation of Wuling tea resources.The highest similarity of all materials between No1 and No2 was 0.93.Dendrogram of the183 tea germplasms were protracted by UPGMA clustering analysis also revealed the genetic diversity and relationship of the tea germplasms of Wuling mountainous area.Besides,fingerprint of the 183 tea germplasms were constructed.

Optimization of Supercritical Fluid Extraction of Tea Flower Polysaccharides by Using Response Surface Method

Polysaccharide production from tea flower(TFPS) was carried out using supercritical fluid extraction(SFE).Response surface methodology(RSM),based on a five level,four variable small central composite design,was employed to obtain the best possible combination of extraction time,pressure,temperature and ethanol content of modifier for maximum production.The optimum conditions were as follows:extraction time of 170 min,pressure of45 MPa,temperature of 75 ℃,and 50% aqueous ethanol solution as modifier.Under these conditions,the experimental yield was 6.56 ± 0.37%,which was similar to the value predicted by the model.Monosaccharide composition of TFPS was fucose,rhamnose,arabinose,xylose,galactose,glucose,mannose,fructose,ribose,galacturonic acid and glucuronic acid in a molar percent of 31.69,0.21,0.49,1.29,35.82,0.97,1.63,18.34,7.88,1.06 and 0.63.Compared to other extraction methods,SFE could achieve higher yield and gain more types of monosaccharide.

Effects of Brewing Conditions on Quality of Pu'erh Tea Infusion

To brew tea correctly is very important to absorb the tea nutrition for people.The dynamic changes of the main compositions in brewing Pu'erh tea processing with different conditions were studied.Three different temperatures and eight times were designed to study the effects on the tea infusion quality.The index t0.5min(50%concentration of compounds in tea infusion) was used to evaluate the extract speed of compound in this experiment.The results showed that caffeine solubility speed at 80℃ was the highest to compare with tea polyphenols,amino acid,caffeine,soluble sugar,theaflavins and theabrownine,t0.5min of caffeine was 4.8 min,amino acid 10.3min was the second,the third one was tea polyphenols,soluble sugar was the lowest.We also found in different infusion temperature the t0.5min of compounds was distinguishing.With increasing the temperature all t0.5min of six compounds were shorter.However,the change regulations of t0.5min for all compounds in 90℃ and 100℃ were similar to in 80℃.Total quality score(TQS) were applied to evaluate the quality of tea infusion.The results found the TQS score of infusion was higher with the temperature rising,and the temperature to brew best quality infusion was 100℃ for 4-5min.According to the multiple regression analysis between sensory assessments and chemical components of Pu'erh tea we suggested the TQS was mainly affected by theaflavins,amino acid,soluble sugar and theabrowine four factors in 100℃.

Benefits of Daily Intake Tea on Human Health

The recent research achievements about the mechanisms of beneficial health effects of tea polyphenols and the epidemiological investigation on anti-cancer,anti-cardiovascular diseases,and anti-obesity through tea consumption were reviewed.It is proved that reactive oxygen species is the main reason to induce cell mutation,DNA damage,obesity,high blood pressure and many kinds of cancers.Tea catechins and theaflavins have excellent bioactivity on scavenging ROS due to their characteristic structure feature of phenolic hydroxyl group,which means drinking tea could prevent diseases.Epidemidogical investigations also showed that tea consumption could reduce the risk of lung cancer,gastric cancer,bladder cancer,and so on.However,the frequency of tea drinking or tea consumption amounts significantly affected the prevention efficiency.The epidemiologic investigations also find that drink green tea,especial black tea is useful to modify the cardiovascular diseases.In vivo and vitro tests showed that tea supplement could moderate the metabolism of blood lipid and prevent obesity.These indicated that tea and tea extracts might reduce the risk of many diseases.

Effect of Chelated Vanadium Spray on Concentration of Vanadium and Organic Compounds in Tea Shoots

The study aimed to develop vanadium tea products and evaluated the potential of chelated vanadium(V)absorption by tea shoots and effect of vanadium accumulation on tea quality during the first crop season.Chelated V application with three times foliar sprays at 5 days intervals starting from 15 days before plucking showed a significant increase in V content of new young shoots,which was much effective at higher concentration.However,one or two times sprays had no increase in V content regardless of spray concentration compared to non-treated.Despite V accumulation in the treated at 3 to 9 times higher that of than the non-treated plants,there were no significant changes in contents of total amino acids,theanine,caffeine,total polyphenols,crude fiber,and cathechins between the treated and the non-treated.

Beta-Glucosidase Activity in Paddy Soils of the Taihu Lake Region, China

The profile distribution of β-gulcosidase activity in twelve typical paddy soil profiles with high productivity in the Taihu Lake region of China were investigated. Activities of β-gulcosidase in the plow layers were in the range of 52.68-137.02 μg PNP g-1 soil h-1 with a mean of 89.22 μg PNP g-1 soil h-1. However, most plow layers ranged from 70 to 110 μg PNP g-1 soil h-1. The profile distribution of β-gulcosidase activity in the 12 soil profiles decreased rapidly with soil depth, with activity at the 60 cm depth only about 10% of that in the surface layers (0-15 cm or 0-20 cm). In these soil profiles, β-gulcosidase activity was significantly positively correlated with soil organic carbon and arylsulphatase activity. Meanwhile, a significantly negative correlation was shown between β-gulcosidase activity and soil pH.

Difference in Selenium Accumulation in Shoots of Two Rice Cultivars

Two japonica rice (Oryza saliva L.) cultivars, Xiushui 48 and S. Andrea, differing in their ability to accumulate Se in the grain (as high as a three-fold difference), were compared for selenium (Se) accumulation in their shoots when their growth media was supplied with different forms of Se. Results indicated that when treated with 0.25μmol L-1 Na2SeO3, Xiushui 48 accumulation of Se in the shoots was significantly more rapid (P≤0.05) than S. Andrea, probably because of greater Se uptake and transport in Xiushui 48. Xiushui 48 rice seedlings had a higher shoot-Se accumulation rate and absorbed selenocysteine (Se-Cys) more rapidly than S. Andrea seedlings. However, when treated with Se as 0.25 f33mol L-1 selenomethionine (Se-Met), the S. Andrea seedlings' accumulation rate was significantly greater (P≤0.05) than that of Xiushui 48. Possibly, the high Se accumulation rate of Xiushui 48 seedling shoots compared to S. Andrea shoots was the result of a higher capacity of Xiushui 48 to transform selenite to organic Se compounds and a higher selenite uptake rate.

Effect of Waterlogged and Aerobic Incubation on Enzyme Activities in Paddy Soil

An incubation experiment with soil water content treatments of 0.15 (W1), 0.20 (W2), and 0.40 (W3) g g-1 soil was carried out for two months to investigate the activities of important enzymes involved in C, N, P, and S cycling in a paddy soil from the Taihu Lake region, China, under waterlogged and aerobic conditions. Compared with air-dried soil, waterlogging resulted in a significant decrease (P (?) 0.05) of fluorescein diacetate (FDA) andβ-D-glucosidase activities, and this effect was enhanced with increasing waterlogging time. Waterlogging also significantly inhibited (P (?)0.05) arylsulfatase as well as alkaline and acid phosphatase activities, but did not decrease the activities with the increase in waterlogging time. Short-term waterlogging did not affect urease activity, but prolonged waterlogging decreased it markedly. In contrast, the aerobic incubation (W1 and W2 treatments) significantly increased (P(?) 0.05) FDA, alkaline phosphatase, andβ-D-glucosidase activities. With aerobic treatments the activities of FDA and alkaline phosphatase increased with incubation time, whereasβ-D-glucosidase activity decreased. A significant difference (P (?) 0.05) was usually observed between the W1 and W2 treatments for the activities of FDA as well as alkaline and acid phosphatase; however,β-D-glucosidase and urease were usually not significant (P(?) 0.05). No activity differences were observed between waterlogging and aerobic incubation for arylsulfatase and urease.

Cytotoxicity of epigallocatechin-3-gallate to LNCaP cellsin the presence of Cu^(2+)

Epigallocatechin-3-gallate (EGCG) has shown remarkably anti-cancer activity, with its bioactivity being related to reactive conditions, such as pH and metal ions. The present study investigated the degradation of EGCG and its effect on prostate cancer cell in the presence of Cu2+. EGCG was incubated with prostate cancer cells, LNCaP, pretreated with or without Cu2+.EGCG in F-12 medium was quantified using HPLC and the viability of cells was assessed by gel electrophoresis, flow cytometry,and electron microscope. The results of HPLC showed that EGCG degraded completely within 12 h in F-12 medium with or without Cu2+. Gel electrophoresis and flow cytometry did not detect apoptosis of LNCaP cells when they were incubated with EGCG. Electron microscopy examination revealed that EGCG-Cu2+ complex led to damage of cytoplasm membrane in LNCaP cells. It was speculated that not EGCG, but its oxide and complex with Cu2+, are the bioactive components responsible for its cytotoxicity to LNCaP prostate cancer cells.

Protective effects of EGCG on Bifenthrin-Induced Oxidative Stress in the Human Embryonic Lung Fibroblast Cell Line HFL-I

Bifenthrin(BF) is an important type I synthetic fluorinated pyrethroid insecticide and acaricide.Previous investigations have indicated that the metabolisms of BF in human cells were through oxidative processes,and cytotoxicity was induced by the oxidative stress.In this study,the protective effects of EGCG,which is a major individual of green tea polyphenols,on the human embryonic lung fibroblast cell line HFL-I exposed to BF were investigated.The results showed that BF could induce oxidative stress leading to cytotoxicity in HFL-I cells.The pretreatment of EGCG at low concentrations significantly recovered the cell viability and morphology,inhibited excess generation of ROS,enhanced antioxidant enzyme activities and avoided loss of mitochondrial membrane potential.The results suggested that EGCG might eliminate the BF-induced damage in HFL-I cells.

Characterization and quantification of two acylated flavonol glycosides from Camellia sinensis and their antibacterial effect on oral pathogens

Acylated flavonol glycosides(AFGs)are a new group of flavonoids with multiple pharmacological functions.In the present work,two AFGs were isolated with a combined chromatography technology from Camellia sinensis and identified as quercetin tetraglycosides with one p-coumaryl moiety(F1)and kaempferol tetraglycosides with one p-coumaryl moiety(F2)by ultra-performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS)and nuclear magnetic resonance(NMR).F1 and F2 with high purity and quantity can be obtained through relatively simple steps,which is of great significance in industrial production and application.The quantification of two AFGs in different tea cultivars and different season samples was conducted using the high-performance liquid chromatography(HPLC)method.Among fifty tested tea cultivars,the contents of F1 and F2 were extremely high in'Zhenghe Dabaicha'and'Wannong 95',but these were undetectable in some tea cultivars.Relatively high contents of AFGs were found in autumn harvested tea samples which might be related to sunlight irradiation.Further in vitro experiments showed that F1 and F2 monomers were effective on inhibiting growth and biofilm development of Porphyromonas gingivalis and Fusobacterium nucleatum.This antibacterial activity was proven to involve the chelation of iron.These results provide useful information on AFGsrich tea resources and new insights of AFGs into effective agents against oral diseases.

Synergistic effects of tea polyphenols and ascorbic acid on human lung adenocarcinoma SPC-A-1 cells

Tea polyphenols have been shown to have anticancer activity in many studies.In the present study,we investigated effects of theaflavin-3-3'-digallate(TF3),one of the major theaflavin monomers in black tea,in combination with ascorbic acid(AA),a reducing agent,and(-)-epigallocatechin-3-gallate(EGCG),the main polyphenol presented in green tea,in combination with AA on cellular viability and cell cycles of the human lung adenocarcinoma SPC-A-1 cells.The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT) assay showed that the 50% inhibition concentrations(IC50) of TF3,EGCG,and AA on SPC-A-1 cells were 4.78,4.90,and 30.62 μmol/L,respectively.The inhibitory rates of TF3 combined with AA(TF3+AA) and EGCG combined with AA(EGCG+AA) at a molar ratio of 1:6 on SPC-A-1 cells were 54.4% and 45.5%,respectively.Flow cytometry analysis showed that TF3+AA and EGCG+AA obviously increased the cell population in the G0/G1 phase of the SPC-A-1 cell cycle from 53.9% to 62.8% and 60.0%,respectively.TF3-treated cells exhibited 65.3% of the G0/G1 phase at the concentration of its IC50.Therefore,TF3+AA and EGCG+AA had synergistic inhibition effects on the proliferation of SPC-A-1 cells,and significantly held SPC-A-1 cells in G0/G1 phase.The results suggest that the combination of TF3 with AA or EGCG with AA enhances their anticancer activity.

The Tea Tree Genome Provides Insights into Tea Flavor and Independent Evolution of Caffeine Biosynthesis

Tea is the world＇s oldest and most popular caffeine-containing beverage with immense economic, medicinal, and cultural importance. Here, we present the first high-quality nucleotide sequence of the repeat-rich （80.9%）, 3.02-Gb genome of the cultivated tea tree Camellia sinensis. We show that an extraordinarily large genome size of tea tree is resulted from the slow, steady, and long-term amplification of a few LTR retrotransposon families. In addition to a recent whole-genome duplication event, lineage-specific expansions of genes associated with flavonoid metabolic biosynthesis were discovered, which enhance catechin production, terpene enzyme activation, and stress tolerance, important features for tea flavor and adaptation. We demonstrate an independent and rapid evolution of the tea caffeine synthesis pathway relative to cacao and coffee. A comparative study among 25 Camellia species revealed that higher expression levels of most flavonoid- and caffeinebut not theanine-related genes contribute to the increased production of catechins and caffeine and thus enhance tea-processing suitability and tea quality. These novel findings pave the way for further metabolomic and functional genomic refinement of characteristic biosynthesis pathways and will help develop a more diversified set of tea flavors that would eventually satisfy and attract more tea drinkers worldwide.

Adsorption of methylene blue onto activated carbon produced from tea (Camellia sinensis L.) seed shells: kinetics, equilibrium, and thermodynamics studies

Tea (Camellia sinensis L.) seed shells, the main byproduct of the manufacture of tea seed oil, were used as precursors for the preparation of tea activated carbon (TAC) in the present study. A high yield (44.1%) of TAC was obtained from tea seed shells via a one-step chemical method using ZnCl2 as an agent. The Brunauer-Emmett-Teller (BET) surface area and the total pore volumes of the obtained TAC were found to be 1 530.67 mg2/g and 0.7826 cm3/g, respectively. The equilibrium adsorption results were complied with Langmuir isotherm model and its maximum monolayer adsorption capacity was 324.7 mg/g for methylene blue. Adsorption kinetics studies indicated that the pseudosecond-order model yielded the best fit for the kinetic data. An intraparticle diffusion model suggested that the intraparticle diffusion was not the only rate-controlling step. Thermodynamics studies revealed the spontaneous and exothermic nature of the sorption process. These results indicate that tea seed shells could be utilized as a renewable resource to develop activated carbon which is a potential adsorbent for methylene blue.

Production of fermented tea petal decoction with insights into in vitrobiochemical tests,antioxidant assay and GC-MS analysis

This research work was designed to attempt and propose the first report on production and biochemical characterization of fermented tea flower petal decoction or simply tea petal wine.The tea petal decoction and brewer’s yeast or Saccharomyces cerevisiae were co-cultured for fermentation.Antioxidant activity and chromatographic separation of potential candidates were assessed.Primary investigations for qualitative characters on this fermented broth revealed the presence of steroids,tannin,flavonoids,phenol,cardiac glycosides,coumarin,caffeine etc.Our manufactured fermented broth showed high free radical scavenging activity after 2 months of aging.High DPPH scavenging activities were also observed in solvent fractions of acetone,ethanol and methanol.The antioxidant activity,alcohol percentage and other qualities were seen to be gradually increased during aging.Gas chromatography-mass spectrometry analysis revealed the presence of 44 compounds including many potential antioxidant molecules and other bioactive agents.Hopefully,presence of alcohol with medicinally active compounds and antioxidant activity will make it as acceptable as a good wine and tea flower as economically functional.