what are polyphenols and how are they extracted and characterised using HPLC from Tea leaves?
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What are they?\n\nTea polyphenols are compounds in tea leaves that are natural plant antioxidants. Antioxidants have been shown to prevent damage caused by free radicals to DNA and other molecules.\n\nHow do they work?\n\nTea polyphenols have demonstrated several cancer preventive properties. In addition to antioxidant activity, these compounds may reduce abnormal cell growth and inflammation; help the body get rid of cancer-causing agents; and restore communication between different cells in the body.\n\nHPLC (high performance liquid chromotography) is a separation technique used to separate a mixture into its individual components.  The polyphenols may be extracted as a group, probably along with other compounds, from the tea leaves with a suitable solvent.  The extract is then, after proper preparation, injected into the HPLC, which will separate the mixture into separate "bands," each a single compound that can then be identified by a molecular spectrometry technique.
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It depends.  There are alot of antioxidants out there.  Some are good for you, such as Vitamin C.  Your body needs antioxidants to prevent free radicals from doing harm to the body.\n\n\nHow some antioxidants can harm health\n\nSome of the plant based reducing acids, most notably oxalic and phytic, bind to needed dietary minerals, rendering them unabsorbable in the gastrointestinal tract. Some of the tannins also have this negative characteristic. Calcium and iron deficiencies are not uncommon in mideastern diets where there is high consumption of phytic acid present in beans and unleavened whole grain bread. Such antinutrients can sometimes result in deceptively high Oxygen Radical Absorbance Capacity (ORAC) ratings given to various "healthy" beverages and foods, particularly:\n\ncocoa/chocolate, spinach, and berries - oxalic acid \nwhole grains - phytic acid \ntea - tannins \nOther extremely powerful nonpolar antioxidants such as eugenol also happen to have toxicity limits that can easily be exceeded with the misuse of essential oils.\n\nHigh levels of antioxidants can be powerful agents against tumours, but in some scenarios can interfere with the effects of other cancer treatments.\n\nRecent laboratory studies suggest that at levels much higher than occur through normal diets, antioxidant vitamins such as A, E and C can have pro-oxidant effects, increasing the formation of free radicals. Natural antioxidants are always ingested together with a wide variety of flavonoids and other phytochemicals are also likely to play a part. Many supplement manufacturers supply products containing antioxidants in combination with these other natural chemicals. Another significant factor is that the mechanisms by which different antioxidants regenerate each other require balanced levels to work optimally. Newer liquid nutritional supplements using plant ionic compounds are believed to be more readily absorbed in the human body.
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http://www.ajpe.org/aj6802/aj680241/aj680241.pdf\n\nThat link explains the process-caffeine and the two you listed are all members of the same chemical family, and can be extracted together.  Be careful though, theophylline is a toxic compound.  Thoebromine is present in higher levels in chocolate than in tea, by the way.
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I like using tea leaves because there is a theroy that every one subconsoiusly knows what there future is and with tea leaves your mind uses matrixing and basicaly it is the same as taking an you ink blot test, you see something but you dont allways know what it means untill you look it up.\nI also like to think of a specific question that i want answered or what i want to look into and randomly pick up a book , a page, and a parragraph. I like using poem books, or my favorite physics book (dont ask)\nI also like using a bead on a string and ask it questions to divine.
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Green tea is mainly used for its anti oxidant qualities. And there are plenty of anti oxidants out there including strawberries-yum!\n\nThe other claims are very suspect especially the weight loss claim.\nSorry there is no magic bullet out there.\nLifestyle change is your answer including an excellent diet and loads of healthy exercise
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these might help..\n\nhttp://www.blackwell-synergy.com/doi/abs/10.1111/j.1365-2621.2006.01347.x\n\nhttp://www.co-lipidology.com/pt/re/colipidology/abstract.00041433-200502000-00009.htm;jsessionid=Fh8fr0yV02g1pkF1LGYLXyzy9lPXZ4Gn69QZKHJ1GG1vJYGw1czy!-1640309041!-949856145!8091!-1\n\nhttp://scholar.google.com/scholar?hl=en&lr=&q=cache:yYCPrA4fU54J:bmc.ub.uni-potsdam.de/cgi-bin/show.pl%3F1475-2891-4-33/1475-2891-4-33.pdf+list+of++biochem+experiments,+TEAC+assay+or+the+phenolics+test
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all tea are a gud source of anti-oxidants which clean ur body up, from the inside
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AHCC, which is an extract of a couple of kinds of mushrooms has been used for centuries for general well-being.  But now is being used by Doctors in Japan to treat cancer by way of strengthing the immune system.  It apparently increases NK (natural killer) cell activity.\n\nGreen Tea Extract is also good for immune system support as is Spirulina.\n\nVitamin C--lots taken several times a day.  Vitamin C has gotten more stupidly ignorant bad press than anything around. \nQuite simply it has a half-life of about 30 minutes.  That means that if you take 1000 milligrams, 30 mins. later only 500 remains, 30 mins. later 250 is left, and so on.  So to keep Vitamin C levels where they need to be to support all of you including your immune system you need to take it a minimum of three times a day--five is better.
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Black Seed Female Energy Tea - 20 bags, (Theramune Nutritionals)\n\nThis energizing tea is formulated to help ladies get into an intimate mood. Made with Black Cohosh, Ginseng, Ginkgo, Black (Cumin) Seed, St.Johns Wort, Gotu Kola, and other herbs. \n \nA unifque new way to enjoy the nutritional benefits of Black Cumin Seed in the form of refreshing herbal tea. \n\nhttp://www.herballoveshop.com/product.asp?PID=1425
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110% gÖd...taste nice....refreashing evrything......Is any other food or drink reported to have as many health benefits as green tea? The Chinese have known about the medicinal benefits of green tea since ancient times, using it to treat everything from headaches to depression.  In her book Green Tea: The Natural Secret for a Healthier Life, Nadine Taylor states that green tea has been used as a medicine in China for at least 4,000 years.  \n\nToday, scientific research in both Asia and the west is providing hard evidence for the health benefits long associated with drinking green tea. For example, in 1994 the Journal of the National Cancer Institute published the results of an epidemiological study indicating that drinking green tea reduced the risk of esophageal cancer in Chinese men and women by nearly sixty percent. University of Purdue researchers recently concluded that a compound in green tea inhibits the growth of cancer cells. There is also research indicating that drinking green tea lowers total cholesterol levels, as well as improving the ratio of good (HDL) cholesterol to bad (LDL) cholesterol.\n\nTo sum up, here are just a few medical conditions in which drinking green tea is reputed to be helpful: \n\ncancer \nrheumatoid arthritis \nhigh cholesterol levels \ncariovascular disease \ninfection \nimpaired immune function\n\nWhat makes green tea so special? \n\nThe secret of green tea lies in the fact it is rich in catechin polyphenols, particularly epigallocatechin gallate (EGCG). EGCG is a powerful anti-oxidant: besides inhibiting the growth of cancer cells, it kills cancer cells without harming healthy tissue. It has also been effective in lowering LDL cholesterol levels, and inhibiting the abnormal formation of blood clots.  The latter takes on added importance when you consider that thrombosis (the formation of abnormal blood clots) is the leading cause of heart attacks and stroke. \n\nLinks are being made between the effects of drinking green tea and the "French Paradox." For years, researchers were puzzled by the fact that, despite consuming a diet rich in fat, the French have a lower incidence of heart disease than Americans. The answer was found to lie in red wine, which contains resveratrol, a polyphenol that limits the negative effects of smoking and a fatty diet.  In a 1997 study, researchers from the University of Kansas determined that EGCG is twice as powerful as resveratrol, which may explain why the rate of heart disease among Japanese men is quite low, even though approximately seventy-five percent are smokers. \n\nWhy don't other Chinese teas have similar health-giving properties? Green, oolong, and black teas all come from the leaves of the Camellia sinensis plant. What sets green tea apart is the way it is processed.  Green tea leaves are steamed, which prevents the EGCG compound from being oxidized. By contrast, black and oolong tea leaves are made from fermented leaves, which results in the EGCG being converted into other compounds that are not nearly as effective in preventing and fighting various diseases.  \n\nOther Benefits \n\nNew evidence is emerging that green tea can even help dieters.   In November, 1999, the American Journal of Clinical Nutrition published the results of a study at the University of Geneva in Switzerland.  Researchers found that men who were given a combination of caffeine and green tea extract burned more calories than those given only caffeine or a placebo.\n\nGreen tea can even help prevent tooth decay! Just as its bacteria-destroying abilities can help prevent food poisoning, it can also kill the bacteria that causes dental plaque. Meanwhile, skin preparations containing green tea - from deodorants to creams - are starting to appear on the market. \n\nHarmful Effects? \n\nTo date, the only negative side effect reported from drinking green tea is insomnia due to the fact that it contains caffeine.   However, green tea contains less caffeine than coff
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DO MORE THAN ONE THING!\n1) FILL A 1 QUART GLASS JAR 1/4 FULL WITH YELLOW DOCK, NETTLES AND CHRYSANTHEMUMM FLOWERS, FILL WITH BOILING WATER, STEEP OVERNIGHT, DRAIN IN THE MORNING, DRINK HALF THEN AND THE REST BEFORE BED 2) MAKE CELERY AND APPLE JUICE IN A JUICER EVERY MORNING. USE 1 BIG APPLE AND 3 CELERY STALKS, ADD WATER TO TASTE AND 3 TABLESPOONS OF A PRODUCT CALLED GREENS PLUS AND I TBS OF MILLED FLAXSEED. HAVE THIS AFTER YOUR TEA. 3) DRINK 8 GLASSES OF WATER A DAY 4) WASH YOUR FACE WITH PHISODERM MORNING AND NIGHT
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There are plenty of teas you can purchase that do not contain caffeine. These teas can give you energy and supply you with antioxidents.
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http://www.nmsl.chem.ccu.edu.tw/tea/SKIN_910721.htm#keratinocytes\n\nThis website might help.
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The antioxidant content of various types of tea has been well studied. An analysis on 20 common brands of tea has shown that they contain widely varying amounts of antioxidants, which are known to help fight off cancer and heart disease among other illnesses.\n\nThe following teas were brewed for 3 minutes each and the antioxidant level is shown below:\nBrand of Tea Catechin content (in milligrams)\nCelestial Seasonings Green Tea 217\nLipton Green Tea 201\nBigelow Darjeeling Blend (black tea) 164\nUncle Lee's Green Tea 157\nStash Premium Green Tea Decaf 53\nTwinings Earl Grey Black Tea 46\nBigelow Constant Comment (black tea) 38\nBigelow Constant Comment Decaf 10\nLipton Lemon Iced Tea 0\nSnapple Peach Iced Tea 0\n\nThe overwhelming of all tea consumed in the U.S. is black tea. The processing method of tea may account for some of the differences in antioxidant levels. Green tea is commonly thought to have more antioxidants than black tea. This was often, but not always the case. Most scientists that have really studied this have found that the number of antioxidants in black tea is actually higher than what is found in green tea.
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None of these ------- forget them.\n\n  Try Stevia. It's from Peru, and is from a vine.\n\n   5 to 10 drops will suffice for a cup of tea, or coffee\n\n  If you were diabetic, I understand it can still be used.\n\n  You will find lots of info' on the net.\n\n   It can be found at health food shops.
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Green Tea is known mainly to come from China and Japon. But also from Ceylon,  Darjeeling Vietnam and Assam\n\nHealth benefits:\n\nProponents of green tea note that its medicinal benefits have been described for over 1000 years. The Kissa Yojoki, or Book of Tea, written by Zen priest Eisai in 1191, describes how drinking green tea can have a positive effect on the five vital organs, especially the heart. The book discusses tea's medicinal qualities which include easing the effects of alcohol, acting as a stimulant, curing blotchiness, quenching thirst, eliminating indigestion, curing beriberi disease, preventing fatigue, and improving urinary and brain function. Part One also explains the shapes of tea plants, tea flowers and tea leaves and covers how to grow tea plants and process tea leaves. In Part Two, the book discusses the specific dosage and method required for individual physical ailments\nIn more recent times, many studies have investigated a link between the consumption of green tea and a lower incidence of a range of cancers in populations, with mixed results. Green tea enthusiasts have claimed it to be useful for:\nCognition \nStopping certain neurodegenerative diseases such as Alzheimers \nPreventing/treating cancer \nTreating arthritis \nTreating multiple sclerosis \nPreventing the degradation of cell membranes by neutralizing the spread of free radicals (which occurs during the process of oxidation).\nIncreases fat oxidation (helps the body use fat as an energy source) and raises metabolism.\nLowering LDL cholesterol (in high doses in lab tests) \nPreventing lowered T-Cells due to HIV - In lab tests, EGCG, found in green tea, was found to prevent HIV from attacking T-Cells. However, it is not known if this has any effect on humans yet.\n\nSo Green Tea is definitely good,  not only for boosting the energy (by it's fat oxydation action) but for a lot of other conditions.\n\nThat's my Best Answer!
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Do you mean Oolong?  Oolong is a chinese tea, somewhere between the "green" and "black" types.\n\nIf this is what you mean, there's more info here:\nhttp://en.wikipedia.org/wiki/Oolong