Living organisms are exposed to a range of oxidizing species which have the potential to damage bio-molecules. Antioxidants protect cellular systems from potentially harmful effects of processes that cause excessive oxidation. The effect of free radicals on proliferating human and rat peripheral lymphocytes and scavenging effect of green tea polyphenols were studied. Exposure to Green tea Polyphenols (low concentration) induced an antioxidant defense mechanism in human and rat peripheral lymphocytes and rat liver.Green tea polyphenols also induce to increase the values of antioxidant defense system of cells such as SOD, POD and Catalase.further more the level of Reduced Glutathione was found to restore to an extent by treatment with polyphenols at low concentration
Unloading, such as a long-term bet rest, immobilization, and weightlessness, causes rapid and marked muscle atrophy. Muscle atrophy caused by immobilization or unloading is associated with oxidative stress and the generation of reactive oxygen species (ROS). This book examine antioxidative effects of polyphenols, such as tea catechins and quercetin, on atrogene expression up-regulated by three dimensional (3D)-clinorotation oxidative stress unloading, such as spaceflight. Catechins and quercetin decreased the expression of atrogenes induced by oxidative stress. Supplementation of antioxidative nutrients, such as catechins and quercetin, might be beneficial for preventing muscle atrophy caused by oxidative stress
It is well known that stress is an important factor, which affects poultry production. High or low ambient temperature, fasting, electric shocks and transportation are typical stressors. Stress induces physiological malfunctions followed by growth inhibition, body fat deposition, lipid peroxidation and suppression of the immune system. Under the stressful condition, the need of antioxidants believed to be increased in order to protect the body tissues. Polyphenols proved to have protective actions against cancer, heart diseases due to its antioxidant ability. However, the roles of polyphenols under stress conditions are still unclear. This work shows that green tea polyphenol could be used as a strong anti-stress agent.
The soybean has been used as a food source for more than 5,000 years. Plant estrogens (phytoestrogens) were first identified in the early 1930s. At that time it was discovered that soybeans, and pomegranates contained compounds that were much like estrogens. Scientists began studying the role isoflavones play in reducing breast cancer risk in the 1960s. In a 1981 prospective study in Japan, researchers found that daily intake of miso,a soybean paste, was linked to lower death rates from stomach cancer in more than 260,000 men and women. Among their many biological activities, the predominant polyphenols in green tea and the theaflavins and thearubigins in black teas have antioxidant activity. Tea Polyphenols have also been shown to inhibit tumor cell proliferation and induce apoptosis in laboratory and animal studies. In other laboratory and animal studies, tea catechins have been shown to inhibit angiogenesis and tumor cell inventiveness.
The antioxidative activity of pure compounds, foods and dietary supplements has been extensively studied in recent years. Activity assays are based on hydrogen ion transfer and electron transfer reactions which do not consider the bioavailability and metabolism issues. The mechanisms of action of antioxidants in biological system go beyond the antioxidant activity and scavenging free radicals. Animal models are expensive and not suitable for initial screening of antioxidative activity of plant extracts. Cell culture models are preferred in initial assessment of antioxidant bioactivity.The extract of Mentha piperita has been commonly used in the treatment of loss of appetite, common cold, bronchitis, sinusitis, fever,nausea, vomition and indigestion as an herbal agent. This piece of work will provide an insite into the antioxidative property of aqueous extract of Mentha piperita which is estimated by both electron transfer assays and cell culture models.
The work presented in the book depicts the extraction, purification and synthesis of tea polyphenols. Extraction and identification of polyphenolic components present in green tea and their purification is a major part of research in the recent past. Enzymatic synthesis of catechin conjugates increases the stability as well as the antioxidant properties of tea catechin. The conjugation reaction of catechin with poly(allylamine) has been studied in aqueous methanol using free, immobilized and cross-linked enzyme crystals (CLEC) of laccase from Trametes versicolor with particular emphasis on the effect of pertinent variables and kinetic aspects of the reaction. A complementary study on adsorption of catechin from aqueous solution on to polymeric resins and activated carbon is described to simplify the separation processes. Emphasis is given in highlighting work for improving the efficiency of extraction of polyphenols from green tea and stability of the polyphenols from the technological perspectives.
Present study describes the antibacterial activity of green tea extracts against dental caries. Green Tea samples were collected from local market of Lahore. The antibacterial activity of water and ethanol extract of Camellia sinensis(L.) Kuntze were examined against Lactobacillus acidophilus and Streptococcus mutans. Antibacterial activity was investigated by paper diffusion test and Minimum inhibitory concentration. Water extract of C. sinensis produce zones of inhibition 6mm-18mm and 8-27mm respectively against Lactobacillus acidophilus and Streptococcus mutans. Ethanol extracts of C. sinensis produced larger zones of inhibition 15-33mm and 19-35mm respectively against Lactobacillus acidophilus and Streptococcus mutans. The minimum inhibitory concentration (MIC) for the green tea water extract against Lactobacillus acidophilus and Streptococcus mutans extract was 0.9mg/ml and 0.8mg/ml respectively. Minimum inhibitory concentration (MIC) for the green tea ethanol extract against Lactobacillus acidophilus and Streptococcus mutans extract was 0.7mg/ml and 0.7mg/ml respectively. Results showed that ethanol extracts of green tea exhibited greater antibacterial activities again
In the present study the samples of the root canal patients were collected and cultured on Blood agar medium. A single colony of E. faecalis was isolated and streaked on blood agar. Disc diffusion method was used to test the antibiotics, mouthwashes and green tea against E. faecalis. Out of the five mouthwashes (Clinica, Colgate, Hi paradent, Macleans and Listerine); maximum antimicrobial activity was showed by Clinica (24.0 ± 0.4 mm). Macleans also showed good results but Listerine showed least effect against E. faecalis. The comparative studies showed a significant difference (p>0.05) between the activity of antibiotics, mouthwashes and green tea. Their antimicrobial activity increased with the increase in concentration. Branded green tea showed maximum antimicrobial activity than the non-branded while each antibiotic used in this study has significant effects against E. faecalis.
Background: Numerous studies indicate that polyphenol rich green tea can reduce several cardiovascular disease (CVD) risk factors. Limited research exists on the impact this beverage has on Scotland. Objective: To investigate the effect of green tea consumption on cardiovascular risk factors in a Scottish population.Design: CVD risk factors such as pulse wave velocity (PWV), total body mass, blood pressure (BP) and total cholesterol were measured in a fasted state at baseline, post green tea (Post GT), post washout (Post WO) and post control (Post CON) periods. Other assessed variables included food intake, height, body mass index (BMI), urine total phenolics and antioxidant capacity. Results: Significant reductions occurred in PWV, p = 0.01, and total body mass, p = 0.012, following green tea consumption. Although not significant marked reductions in BP ,p = 0.065, and total cholesterol , p = 0.009, and increases in total polyphenols, p= 0.035, and antioxidant capacity, p= 0.030, were observed following subject stratification as responders or non-responders. Conclusion: Regular green tea consumption appears to reduce overall CVD risk.
Reactive oxygen species are highly reactive to damage nucleic acids, proteins, lipids and carbohydrates that consequently affect the immune functions causing degenerative diseases, cancer, premature aging, inflammation, cardiovascular and metabolic dysfunction. Antioxidants are known to defuse free radicals leading to limited risk of oxidative stress and associated disorders. Carotenoids, tocopherols, ascorbates and polyphenols found in abundance in various fruits are strong natural antioxidants with free radical scavenging activity (FRSA). Polyphenols are excellent antioxidant with significant importance to reduce oxidative stress and play a key role in human health in protection against degenerative diseases. Some fruits and their underutilized parts were studied for total phenolic contents, antioxidant activity and FRSA in terms of IC50 (inhibitory concentration), EC50 (effective concentration), ARP (antiradical power) and concentration dependent reducing power, expressed as ascorbic acid equivalent (ASE/ml).
Atherosclerosis is a cardiovascular disease which is characterised by the degradation of arterial wall resulting in blockage of the arterial lumen with cholesterol, lipoproteins, plaques and other fibrous substances. This disease has its first impact on the endothelial cell, thus damaging its integrity. Certain drugs like acetylcholine (endothelium dependent) and sodium nitroprusside (endothelium independent) can lead to vasorelaxation. In oxidative stress condition the vasorelaxants fail to show its effect leading to oxidation of NO to form peroxynitrite (ONOO-) which is a lethal product. Oxidants like hydrogen peroxide can lead to oxidation of NO and thus suppressing the activity of Ach. Vasoconstrictor drugs like phenylephrine can lead to narrowing of the blood vessels thus causing contraction of the smooth muscle. Green tea components- epigallocatechin gallate (ECGC) and quercetin has been proved to possess anti oxidant activity to combat the effect of oxidants. This study aimed at investigating the anti oxidant potential of green tea to prevent atherosclerosis.
Polyphenols are the most abundant antioxidants in the diet and are widespread constituents of fruits, vegetables, dry legumes, chocolate, and beverages. The products manufactured from fruits also contain polyphenols in significant amounts. Typically a glass of red wine or a cup of tea or coffee contains about 100 mg polyphenols. Polyphenols or polyphenol rich diets provide significant protection against the development and progression of many chronic pathological conditions including diabetes, cardio-vascular and neurodegenerative diseases or osteoporosis. Our research is focused on the benefits of polyphenols extracted from the black grapes seeds (BGSP), Sambucus nigra or Aronia melanocarpa fruits by using as experimental model the streptozotocin-induced diabetes mellitus on the Wistar white rats. The results of our studies presented in this paper provide a current understanding on the biological effects of polyphenols and their relevance to health. The role of polyphenols in human health is still a less known area of research as polyphenols have proven to offer great hope for the prevention of chronic human diseases.
To study the antioxidative, antitumor and immunomodulatory activity of protein fractions of leaves of Cynodon dactylon and Terminalia catappa on Swiss albino mice. The protein fractions were administered intraperitoneally in mice. The antioxidative and antitumor activity were analysed by liver marker enzymes, enzymic and nonenzymic antioxidants, lipid peroxidation and histological status of liver. The assessment of immunomodulatory activity on humoral and cell mediated immunity were studied by lymphoid organ weight, total leukocyte count, neutrophil adhesion, phagocytic index, antibody titre and protein profile. The results of the study suggested the antioxidative efficacy by enhancing the antioxidative enzymic and non enzymic status, antilipidperoxidative role by inhibiting the lipid peroxide status, antitumorigenic against ELA tumor by increasing the ILS and immunostimulatory against the pyrogallol by the enhancement of the humoral and cell mediated immune responses by the administration of C. dactylonPF and T. catappaPF. Thus Cdpf and Tcpf could be exploited as an antioxidative, antitumorigenic and immunostimulatory agents to combat the oxidative degenerative diseases.
The main objective of this study was to characterize the antioxidant properties of Australian-grown ‘Wonderful’ pomegranate juice (WPJ) in comparison to those reported in the literature and imported pomegranate juices (IPJs). Total phenolic compounds (TPC) and antioxidant (AA) activity in the WPJ were found to be 2,400±200 mg/L GAE (Gallic acid equivalent) and 11±1 TEAC (Trolox® equivalent antioxidant capacity), respectively. While four brands of IPJs showed TPC levels in the range of 1,000-2,800 mg/L GAE and AA range of 5.5-14.5 TEAC. In an attempt to further improve the TPC levels in fresh juice different parts of the fruit were used for juice extraction using six different extraction methods. The extracted juices showed different yield, colour, soluble solids, titratable acidity, TPC and antioxidant levels. To further facilitate the consumers’ access to the health benefits of pomegranate, probiotic yoghurt supplemented with different levels of WPJ concentrate (50 ?Brix) was developed. The maximum level of supplementation without adversely affecting product attributes and probiotic count was 6 % while maintaining maximum antioxidant activity in the product during its shelf life.