Posts Tagged ‘antioxidants’


Wednesday, February 2nd, 2011

Vancouver, British Columbia

Food scientists at the University of British Columbia have been able to pinpoint more of the complex chemistry behind coffee’s much touted antioxidant benefits, tracing valuable compounds to the roasting process. Lead author Ami Ya Zheng Liu and co author Prof. David Kitts found that the prevailing antioxidants present in dark roasted coffee brew extracts result from the green beans being browned under high temperatures.

Their findings will appear in a forthcoming issue of Food Research International.

Liu and Kitts analyzed the complex mixture of chemical compounds produced during the bean’s browning process, called the “Maillard reaction.” The term refers to the work by French chemist Louis-Camille Maillard who in the 1900s looked at how heat affects the carbohydrates, sugars and proteins in food, such as when grilling steaks or toasting bread.

Antioxidants aid in removing free radicals, the end products of metabolism which have been linked to the aging process.

“Previous studies suggested that antioxidants in coffee could be traced to caffeine or the chlorogenic acid found in green coffee beans, but our results clearly show that the Maillard reaction is the main source of antioxidants,” says Liu, an MSc student in the Faculty of Land and Food Systems (LFS).

“We found, for example, that coffee beans lose 90 per cent of their chlorogenic acid during the roasting process,” says Kitts, LFS food science professor and director of the Food, Nutrition and Health program.

The UBC study sheds light on an area of research that has yielded largely inconsistent findings. While some scientists report increased antioxidant activity in coffee made from dark roasted beans, others found a decrease. Yet other theories insist that medium roast coffees yield the highest level of antioxidant activity.

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Friday, April 10th, 2009

Olive Leaf Extract is made from the leaves of the olive tree. The leaves are the main part used in extracting the herbal medicine. The olive tree belongs to the family Oleaceae and is native to the Metiteranian areas of Asia Minor and Syria.
Olive Leaf use as a herbal remedy dates back to ancient Greece. Hippocrates prescribed olive oil for many ailments including ulcers.
Olive Leaf It was around 1900 that the secoiridoid compound oleuropein was isolated from the Olive Leaf, and Olive Leaf Extract came into use in modern society. Since then other secoiridoids, ligustroside and oleacein have been found in the Olive Leaf. They also contain the triterpenoids oleanolic acid and uvaol. As well as the flavonoids chrysoeriol, apigenin, luteolin glycosides, quercitin and kaempferol.
This herbal extract is loaded with sterols and antioxidants.

>>>>>Read on in our Herbal Page in the Diet section.


Saturday, August 2nd, 2008

More evidence for the beneficial effect of green tea on risk factors for heart disease has emerged in a new study reported in the latest issue of European Journal of Cardiovascular Prevention and Rehabilitation.

1. The study found that the consumption of green tea rapidly improves the function of (endothelial) cells lining the circulatory system; endothelial dysfunction is a key event in the progression of atherosclerosis. The study, performed by Dr Nikolaos Alexopoulos and colleagues at the 1st Cardiology Department, Athens Medical School in Greece, was a randomised trial involving the diameter measurement (dilatation) of the brachial artery of healthy volunteers on three separate occasions - after taking green tea, caffeine, and hot water (for a placebo effect). The measurements were taken at 30, 90 and 120 minutes after consumption. Dilatation of the brachial artery as a result of increased blood flow (following a brief period of ischaemia of the upper limb) is related to endothelial function and is known to be an independent predictor of cardiovascular risk.

2.Results showed that endothelium-dependent brachial artery dilatation increased significantly after drinking green tea, with a peak increase of 3.9 per cent 30 minutes after consumption. The effect of caffeine consumption (or hot water) was not significant.

While black tea has been associated with improved short and long-term endothelial performance, this is the first time that green tea has been shown to have a short-term beneficial effect on the large arteries. Another study has already shown that green tea reverses endothelial dysfunction in smokers.

Green tea, which originates in China but is now consumed throughout the world, is made with pure leaves, and has undergone little oxidisation during processing. The cardiovascular benefits of all teas - as well as dark chocolate and red wine - are attributed to the flavonoids they contain and their antioxidant activity.3 However, says investigator Dr Charalambos Vlachopoulos, flavonoids in green tea are probably more potent antioxidants than in black tea because there has been no oxidisation.

“These findings have important clinical implications,” says Dr Vlachopoulos. “Tea consumption has been associated with reduced cardiovascular morbidity and mortality in several studies. Green tea is consumed less in the Western world than black tea, but it could be more beneficial because of the way it seems to improve endothelial function. In this same context, recent studies have also shown potent anticarcinogenic effects of green tea, attributed to its antioxidant properties.”

Press release July 2, 2008