The bitter the better



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November 24, 2008  
Filed under Uncategorized



CM NEWS – A recent study identifies for the first time antioxidant properties of many Chinese herbs that regulates blood circulation. It discovers the herbs traditionally categorized as “bitter” and “sour” in flavours carry more antioxidants than others.

The study was a joint investigation between the Southern Cross University in Australia and Shanxi Provincial People’s Hospital in China.

According to literature, there is a close relationship between antioxidant acitivity and classification of Chinese herbs as yin or yang. In this study, 45 Chinese herbs with traditional characteristics of natures (cold, cool, hot and warm), flavours (pungent, sweet, sour, bitter, salty) and functions (arresting, bleeding, promoting blood flow to relieve stasis, nourishing blood and clearing away heat from blood) were examined.

Antioxidant activity was measured using the oxygen radical absorbance capacity (ORAC) assay.

What is antioxidant? An antioxidant is a molecule capable of slowing or preventing the oxidation of other molecules. Oxidation is a chemical reaction that transfers electrons from a substance to an oxidizing agent. Oxidation reactions can produce free radicals, which start chain reactions that damage cells. Antioxidants terminate these chain reactions by removing free radical intermediates, and inhibit other oxidation reactions by being oxidized themselves. As a result, antioxidants are often reducing agents such as thiols or polyphenols.

According to the researchers, TCM believes that the different characters of herbs are employed to treat diseases, rectify the hyperactivity or hypoactivity of yin or yang and help the body restore its normal physiologic functions.

What is Artemisia anomala? Artemisia anomala belongs to the family Compositae, and is a fragrant shrub that grows widely in the Zhejiang region of China. Phytochemical analysis of A. anomala shows that it is a rich source of phenolic compounds, such as flavonoids including eupatilin and arteanoflarone. The presence of phenolic compounds (phenolic acids, polyphenols and flavonoids) in herbs and spices, along with the essential oils, is gaining increasing attention because of their various functions, such as antioxidant activity and flavouring properties.

“All herbs possess four natures and five flavours. The four natures—cold, hot, warm and cool are summarized mainly from the body’s response after Chinese herbs are taken, which are so defined in relation to the properties, cold or heat of the diseases treated.”

The researchers say there are some herbs known as neutral ones, “whose cold or hot nature is not so remarkable and whose action is relatively mild, but these herbs still have differences in their tendencies to cool or warm so that they are still in the range of four natures.”

What is spatholobus suberectus vine? Spatholobus suberectus is a traditional Chinese herbal medicine used to treat rheumatism, anemia, menoxenia, and other disorders.

The five flavours are the pungent, sweet, sour, bitter and salty that can be tasted with the tongue. With the development of the theory dealing with the medicinal properties, the flavours could best be described as abstract concepts, as the flavour definitions have arisen more from observations of the clinical actions of the herbs than from the taste sensations.

The results show that herbs with bitter and/or sour flavour have an ORAC value 4 times higher than herbs with sweet and/or pungent flavour. Ten herbs had an ORAC value that was similar or higher than that of vitamin E.

High antioxidant herbs were identified as Spatholobus suberectus vine (xuefengteng ???), Sanguisorba officinalis root (diyu ??), Agrimonia pilosa herb (xianhecao ???), Artemisia anomala herb (qigao ?? or ????), Salvia miltiorrhiza root (danshen ??) and Nelembo nucifera leaf (hehua or lotus ??).

What is Salvia miltiorrhiza root? Salvia miltiorrhiza is among the most popular medicinal herbs used in China. It has been used in the treatment of stroke since 1970, angina and heart attack, as an antihypertensive and a sedative. S. miltiorrhiza contains several compounds that are pharmacologically active, especially the diterpenoids known as tanshinones.

What is Sanguisorba officinalis root? Sanguisorba officinalis root has been used in TCM to stop bloody dysentery, nosebleeds, and is applied topically to treat burns and insect bites.

[eCAM 2008 5(4):429-434; doi:10.1093/ecam/nem054]