Influence Of Tea Polyphenols Research Articles

Influence of Tea Polyphenols, Chitosan, and Melatonin as the Eco-Friendly Post-Harvest Treatments on the Vase Life of the Cut Chrysanthemum ‘Pingpong’ Group

Vase life is a decisive measure of the marketability of post-harvest physiology in cut flowers. In the process of petal senescence, the cut chrysanthemum (Chrysanthemum × morifolium) ‘Pingpong’ group develops severe capitulum collapse which manifests as wilting and browning, leading to shorter vase life. Melatonin (MT), tea polyphenols (TPs), and chitosan (CT) are natural alternatives to chemical compounds with proven preservation effects. In this study, the possibility of mitigating capitulum collapse using the preservation solutions of these three eco-friendly ingredients was investigated on four varieties from the ‘Pingpong’ group, aiming to delay the senescence process. The effects on vase life of 0.02/0.04 mmol·L−1 MT, 200/400 mg·L−1 TPs, and 0.10/0.20 g·L−1 CT were, respectively, assessed with the basis of 20 g·L−1 sucrose and 250 mg·L−1 citric acid. The yellow and white varieties tend to have a longer vase life compared with the green and pink varieties. Compared to the control with only base ingredients, the greatest delay in capitulum collapse was observed with 0.04 mmol·L−1 MT in the yellow variety, maximizing the vase life to 13.4 days. MT maintained the best ornamental quality of the capitulum by decelerating fresh weight and flower diameter loss in terms of all varieties. TPs significantly increased flower diameter to improve vase life up to four more days. However, CT caused significant negative effects on vase life, with severe loss of both flower diameter and fresh weight. Therefore, the application of 0.04 mmol·L−1 MT and 200 mg·L−1 TPs was suggested to enhance the marketability of cut ‘Pingpong’, which highlighted the eco-friendly potential of post-harvest treatments.

A novel strategy to transform mango peel waste into useful product– Preparing antibacterial film containing tea polyphenols for chicken breast preservation

Studies on the use of antibacterial packaging films to delay the deterioration of meat products are gaining interest. Many petroleum-based packaging materials are difficult to degrade, seriously pollute the environment, and pose a threat to human health. This study aimed to prepare antibacterial packaging films using mango peel waste for chicken breast stored at 4 °C for 12 days. The influence of tea polyphenols on various film properties was characterized and changes in various physicochemical indicators of chicken breast meat during storage were determined. Scanning electron micrographs showed that tea polyphenols made the mango peel antibacterial film denser, and their introduction reduced water vapor transmission by 32.5%, oxygen transmission rate by 84.3%, carbon dioxide transmission rate by 80.0%. The mango antibacterial film containing 1.4 g/hg tea polyphenols effectively maintained the color and texture of chicken breast meat and inhibited water loss, pH increase, microbial growth, reproduction, and reduce the production of thiobarbituric acid by 19.0% and volatile alkali nitrogen by 60.6% in chicken breast meat, indicating that chicken breasts wrapped in this film had a longer shelf life. This study provides a basis for the further application of mango peel antibacterial films in the food industry.

In vitro effects of tea polyphenols on the secretion of TNF-α, IFN-γ and IL-2R by peripheral blood CD8＋ T lymphocytes from vitiligo patients

Objective To detect the level of cytokines and their receptors secreted by peripheral blood CD8＋ T lymphocytes from vitiligo patients, and to evaluate the influence of tea polyphenols on their secretion. Methods CD8＋ T lymphocytes were isolated from the peripheral blood of 12 patients with progressive vitiligo, 12 patients with stable vitiligo and 10 healthy controls, and cultured in vitro for 20 days. Then, some CD8＋ T lymphocytes were treated with tea polyphenols of 100 mg/L for two days. Enzyme-linked immunosorbent assay （ELISA） was carried out to determine the levels of tumor necrosis factor （TNF）-a, interferon （IFN）-a and interleukin-2 receptor （IL-2R） in the culture supernatants of CD8＋ T lymphoeytes before and after the treatment with tea polyphenols. Analysis of variance and t test were conducted to assess differences in these parameters among these groups and changes between pretreatment and posttreatment, respectively. Results There was a sequential decrease in the level of TNF-a （（ 191.302±6.077） vs. （175.966± 2.467） vs. （173.664 ± 3.600） ng/L, F = 4.784, P 〈 0.05）, bat a sequential increase in that of IFN-a （ （280.182 ± 36.070） vs. （371.670 ± 24.352） vs. （447.147 ± 8.432） ng/L, F= 9.036, P〈 0.01） and IL-2R （（8.375 ± 0.161） vs. （8.845 ±0.161） vs. （9.345 ± 0.125） ng/L, F = 9.639, P 〈 0.01） in the culture supernatant of CD8＋ T lymphocytes from patients with progressive vitiligo to patients with stable vitiligo and healthy controls. After two days of tea polyphenol treatment, a statistical decrease was observed in the level of TNF-a in the culture supematant of CD8 ＋ T lymphocytes from patients with progressive vitiligo （（ 164.797 ± 1.784） ng/L, P 〈 0.01 ）, patients with stable vitiligo （（166.150 ± 3.576） rig/L, P 〈 0.05） and healthy controls （（155.028 ± 5.759） ng/L, P 〈 0.05）, but no statistical changes were noted for IFN-＇y or IL-2R （all P 〉 0.05） despite a slight elevation in the level of IFN-＇y in the culture supernatant of CD8＋ T lymphocytes from patients with stable vitiligo and in that of IL-2R from all the three groups as well as a mild reduction in that of IFN-Y from patients with progressive vitiligo and healthycontrols. Conclusions The changes of cytokines and their receptors secreted by CD8＋ T lymphocytes may be associated with the induction and progression of vitiligo. Tea polyphenols may treat vitiligo via suppressing the secretion of TNF-a by CD8＋ T lymphocytes. Key words: Vitiligo, CDS-positive T-lymphocytes; Tumor necrosis factor alpha; Interferon type II; Recep-tors, interleukin-2; Tea polyphenols

Effects of tea polyphenols on the post-mortem integrity of large yellow croaker (Pseudosciaena crocea) fillet proteins

Tea polyphenols (TP) are known to be important for the post-mortem deterioration of fish muscle and can enhance food quality. To shed light on the influence of TP on the status of large yellow croaker muscle proteins, control and treated fillets (0.1% TP, 0.2% TP and 0.3% TP, w/v) were analysed periodically for myofibrillar protein functional properties (Ca2+-ATPase activity, surface hydrophobicity, total sulfhydryl content, emulsion stability index and rheological behaviour). Degradation of the myofibrillar protein myosin could be clearly observed; several proteins were also observed to vary in abundance following post-mortem storage for 25days. The present study offers new evidence that TP have an effective impact on muscle protein integrity post-mortem.

The impact of polyphenols on the hippocampal neuronal apoptosis and ethology of rats after global cerebral ischemia-reperfusion injury

Objective Observe the influence of tea polyphenols on hippocampal neuronal apoptosis in CA1 region of rats after global cerebral ischemia/reperfusion (I/R) injury,and discuss the relationship between rat's neuronal behavior and hippocampal neuronal apoptosis in addition. Methods 216 healthy male SD rats were randomly divided into 3 groups:sham operation group (SO group,n=72),ischemia/reperfusion group (I/R group,n=72) and tea polyphenols group (TP group,n=72,TP 200 mg/kg,TP were intraperitoneally injected at the time of reperfusion),TUNEL was used to observe,qualitative and locate apoptotic neurons,flow cytometry was used to detected apoptotic index.The open field test and the high cross maze were used to test the rats′ neuroethology.Results After cerebral ischemia/reperfusion injury, TUNEL assay showed that: compared with TP group,hippocampal neurons in CA1 region ofI/R group can be seen more apoptotic cells.Apoptotic cells tested by flow cytometry showed:the apoptosis of TP group reached 26％,compared with the I/R group,the rate of apopotosis was significantly reduced (P＜0.05).Open-field test and elevated plus maze experiments showed that:compared withI/R group,TP group showed some activity and the ability to explore and their emotions are more stable (P＜0.05). Conclusions After cerebral ischemia/reperfusion,tea polyphenols can play the role of anti-apoptosis,reducing the rate of cellular apoptosis in hippocampal CA1 region and it was.able to improve rats′ neurological ethology based on this function. Key words: Brain; Ischema/reperfusion injury; Ethology; Apoptosis; Tea polyphenols